Virology. 2004 Sep 1;326(2):203-19.

The human immunodeficiency virus (HIV) integrase (IN) must covalently join the viral cDNA into a host chromosome for productive HIV infection. l-Chicoric acid (l-CA) enters cells poorly but is a potent inhibitor of IN in vitro. Using quantitative real-time polymerase chain reaction (PCR), l-CA inhibits integration at concentrations from 500 nM to 10 microM but also inhibits entry at concentrations above 1 microM. Using recombinant HIV IN, steady-state kinetic analyses with l-CA were consistent with a noncompetitive or irreversible mechanism of inhibition. IN, in the presence or absence of l-CA, was successively washed. Inhibition of IN diminished, demonstrating that l-CA was reversibly bound to the protein. These data demonstrate that l-CA is a noncompetitive but reversible inhibitor of IN in vitro and of HIV integration in vivo. Thus, l-CA likely interacts with amino acids other than those which bind substrate.

Biol Pharm Bull. 2004 Jul;27(7):1004-9.

Antioxidant and immuno-enhancing effects of Echinacea purpurea.

Mishima S, Saito K, Maruyama H. Api Co., Ltd. NAGARAGAWA Research Center, Nagara, Gifu, Japan.

We studied the protective effects of Echinacea purpurea against radiation by evaluating changes in the peripheral blood cell count and peripheral blood antioxidant activity. E. purpurea administration had a suppressive effect on radiation-induced leukopenia, especially on lymphocytes and monocytes, and resulted in a faster recovery of blood cell counts. Mouse peripheral blood antioxidant activity was increased by E. purpurea, and a relationship between the suppressive effect on radiation-induced leukopenia and the antioxidant effect was suggested. Furthermore, we reviewed the evidence of augmentation of found in this study humoral immunity. The effects of immune activation by E. purpurea were investigated by measuring total immunoglobulin (IgG, IgM). The radioprotective effects of immune activation by E. purpurea were investigated by measuring T lymphocyte subsets in the peripheral blood of mice following whole-body irradiation. E. purpurea activates macrophages to stimulate IFN-gamma production in association with the secondary activation of T lymphocytes, resulting in a decrease in IgG and IgM production. Cytokines released from macrophages in mouse peripheral blood after E. purpurea administration activated helper T cells to proliferate. In addition, it is reported that activated macrophages in association with the secondary T lymphocyte activation increases IFN-gamma production and stimulates proliferation of cytotoxic T cells and suppressor T cells. We think that CD 4 and CD 8 subsets were more immunologically enhanced by E. purpurea than helper T cells and suppressor T cell these results reflect activation. In addition, we think that these results reflect cell-mediated immune responses.

Medicina (Kaunas). 2004;40(7):657-62.

Clin Infect Dis. 2004 May 15;38(10):1367-71. Epub 2004 Apr 26.

Echinacea purpurea for prevention of experimental rhinovirus colds.

Sperber SJ, Shah LP, Gilbert RD. Department of Internal Medicine, Hackensack University Medical Center, Hackensack, NJ, USA.

A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the ability of Echinacea purpurea to prevent infection with rhinovirus type 39 (RV-39). Forty-eight previously healthy adults received echinacea or placebo, 2.5 mL 3 times per day, for 7 days before and 7 days after intranasal inoculation with RV-39. Symptoms were assessed to evaluate clinical illness. Viral culture and serologic studies were performed to evaluate the presence of rhinovirus infection. A total of 92% of echinacea recipients and 95% of placebo recipients were infected. Colds developed in 58% of echinacea recipients and 82% of placebo recipients (P=.114, by Fisher's exact test). Administration of echinacea before and after exposure to rhinovirus did not decrease the rate of infection; however, because of the small sample size, statistical hypothesis testing had relatively poor power to detect statistically significant differences in the frequency and severity of illness.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Clin Chim Acta. 2004 May;343(1-2):161-6.

BACKGROUND: Echinacea is commonly used in oral dosage as an immune stimulant to increase resistance to viral, bacterial and fungal infections of the upper respiratory tract. It has been suggested that Echinacea is able to stimulate innate immune responses, including those regulated by macrophages and natural killer cells. Indeed, macrophages respond to purified polysaccharide and alkylamide preparations. However, the mechanisms for stimulation of cells responsible for adaptive immunity have not been fully elucidated for other molecules present in Echinacea purpurea preparations. METHODS: Adherent and non-adherent mouse splenocyte populations were incubated in vitro with Echinacea, or with water or alcohol soluble Echinacea extract preparations. Supernatants were collected at 48-h post-incubation, and tested by standard ELISA for presence of secreted cytokines and proinflammatory mediators. RESULTS: Whole splenocyte populations were capable of producing significant amounts IL-6 (1014 pg/ml) in response to Echinacea preparations. The response was primarily contained towards products isolated to the water extract preparation; no IL-6 was produced upon challenge with the alcohol extract. The IL-6 response was produced by the non-adherent cellular population, which made 4912 pg/ml IL-6 when treated with water soluble extract at 1 mg/ml. Likewise, the water soluble extract of Echinacea was able to stimulate non-adherent splenocyte populations to produce TNF-alpha (2082 pg/ml), IL-10 (892 pg/ml) and MIP-1alpha (6486 pg/ml) from non-adherent splenocytes, but only significant concentrations of TNF-alpha and MIP-1alpha mediators were produced from adherent populations at similar dose concentrations. Neither population of splenocytes was capable of stimulating significant production of IFN-gamma, IL-2 or IL-12 to any preparation of Echinacea examined. CONCLUSIONS: The immune stimulatory ability of components contained within E. purpurea extracts offer insight into possible therapeutic potential of this product to regulate non-adherent lymphocytes in immune responses and activation events.

J Pharm Biomed Anal. 2004 Apr 16;35(2):289-301.

The aim of this study was to set up and validate an RP-LC method with DAD-detection to quantify caffeic acid derivatives in various Echinacea spp. Samples were extracted with 80% methanol. The analyses were carried out on a Lichrospher RP-18 column (125 mm x 4 mm i.d., 5 microm), with a mobile phase gradient, which increases the acetonitrile level in a phosphoric acid solution (0.1%). The flow rate was 1.5 ml/min. Detection was set at 330 nm. This method allowed the identification and quantification of caftaric acid, chlorogenic acid, caffeic acid, cynarin, echinacoside and cichoric acid in Echinacea roots and derivatives. The total phenolic content was 10.49 mg/g for E. angustifolia, 17.83 mg/g for E. pallida and 23.23 mg/g for E. purpurea. Among Echinacea commercial herbal medicines, a certain variability in the concentrations of phenolic compounds was observed. The radical scavenging activity of Echinacea methanolic extracts was evaluated in vitro with a spectrophotometric method based on the reduction of an alcoholic 2,2-diphenyl-1-picrylhydrazyl (DPPH*) radical solution at 517 nm in the presence of a hydrogen donating antioxidant. As for pure compounds, echinacoside had the highest capacity to quench DPPH* radicals (EC50 = 6.6 microM), while caftaric acid had the lowest (EC50 = 20.5 microM). The average EC50 values for E. purpurea, E. pallida and E. angustifolia were 134, 167 and 231 microg/ml, respectively. The radical scavenging activity of Echinacea root extracts reflected their phenolic composition. The results indicate that Echinacea roots and derivatives are a good source of natural antioxidants and could be used to prevent free-radical-induced deleterious effects.

Arzneimittelforschung. 2004;54(2):114-8.

Arch Pediatr Adolesc Med. 2004 Mar;158(3):217-21.

Effectiveness of an herbal preparation containing echinacea, propolis, and vitamin C in preventing respiratory tract infections in children: a randomized, double-blind, placebo-controlled, multicenter study.

Cohen HA, Varsano I, Kahan E. Pediatric and Adolescent Ambulatory Community Clinic, Petach Tikva, Israel.

OBJECTIVE: To evaluate the effectiveness and safety of a preparation containing echinacea, propolis, and vitamin C in the prevention of respiratory tract infections in children during a 12-week winter period. DESIGN: Randomized, double-blind, placebo-controlled study. SUBJECTS: Four hundred thirty children, aged 1 to 5 years, were randomized to an herbal extract preparation (n = 215) or a placebo elixir (n = 215). INTERVENTION: Administration of an herbal preparation (Chizukit) containing 50 mg/mL of echinacea, 50 mg/mL of propolis, and 10 mg/mL of vitamin C, or placebo (5.0 mL and 7.5 mL twice daily for ages 1 to 3 years and 4 to 5 years, respectively) for 12 weeks. RESULTS: Significant mean +/- SD reductions of illnesses were seen in the Chizukit group in the number of illness episodes, 138 vs 308 (55% reduction); number of episodes per child, 0.9 +/- 1.1 vs 1.8 +/- 1.3 (50% reduction, P<.001); and number of days with fever per child, 2.1 +/- 2.9 vs 5.4 +/- 4.4) (62% reduction, P<.001). The total number of illness days and duration of individual episodes were also significantly lower in the Chizukit group. Adverse drug reactions were rare, mild, and transient. CONCLUSION: A preventive effect of a product containing echinacea, propolis, and vitamin C on the incidence of respiratory tract infections was observed.

Publication Types:

•  Clinical Trial

•  Multicenter Study

•  Randomized Controlled Trial

J Clin Pharm Ther. 2004 Feb;29(1):75-83.

Efficacy of a standardized echinacea preparation (Echinilin) for the treatment of the common cold: a randomized, double-blind, placebo-controlled trial.

Goel V, Lovlin R, Barton R. Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.

BACKGROUND: Recently, echinacea has regained popularity as one of the treatments chosen most commonly by consumers with the expectation that it will reduce the severity and duration of the common cold. However, the results from a limited number of clinical trials for this application have thus far been inconclusive. This incongruity may be the result of investigators utilizing poorly standardized echinacea products, likely devoid of sufficient quantities of active constituents necessary to exert a definitive clinical effect. Therefore, a formulation containing alkamides, cichoric acid, and polysaccharides at concentrations of 0.25, 2.5, and 25 mg/mL, respectively, was prepared from freshly harvested Echinacea purpurea plants (commercially available as Echinilin, Natural Factors Nutritional Products, Inc., Vancouver, BC, Canada). The objective of this study was to test the efficacy of this highly standardized formulation in reducing the severity and duration of symptoms of a naturally acquired common cold. METHODS: In a randomized, double-blind, placebo-controlled trial, 282 subjects aged 18-65 years with a history of two or more colds in the previous year, but otherwise in good health, were recruited. The subjects were randomized to receive either echinacea or placebo. They were instructed to start the echinacea or placebo at the onset of the first symptom related to a cold, consuming 10 doses the first day and four doses per day on subsequent days for 7 days. Severity of symptoms (10-point scale: 0, minimum; 9, maximum) and dosing were recorded daily. A nurse examined the subjects on the mornings of days 3 and 8 of their cold. RESULTS: A total of 128 subjects contracted a common cold (59 echinacea, 69 placebo). The total daily symptom scores were found to be 23.1% lower in the echinacea group than in placebo in those who followed all elements of the study protocol (P<0.01). Throughout the treatment period, the response rate to treatments was greater in the echinacea group. A few adverse event profiles were observed in both groups. CONCLUSIONS: Early intervention with a standardized formulation of echinacea resulted in reduced symptom severity in subjects with naturally acquired upper respiratory tract infection. Further studies with larger patient populations appear to be warranted.

Immunopharmacol Immunotoxicol. 2003 Nov;25(4):551-60.

Enhancement of the humoral immune response by Echinacea purpurea in female Swiss mice.

Freier DO, Wright K, Klein K. Department of Biological Sciences, Mount Holyoke College , South Hadley , Massachusetts , USA .

Various preparations of the plant Echinacea purpurea have been investigated for their potential to enhance immune function, primarily through activation of innate immune responses. Few studies have examined the potential for enhancement of humoral immunity. Using female Swiss mice we administered a volumetric dose of a glycerine extract of E. purpurea by oral gavage, to evaluate effects on the IgM specific antibody forming cell (AFC) response. Four days of treatment following immunization with sheep red blood cells (SRBC) produced a significant enhancement over naive controls at doses of 0.4 and 0.8 mL/kg/day. A few clinical trials and anecdotal reports have suggested that the greatest efficacy for E. purpurea occurs in acute use following onset of illness. A time course study, using the time of SRBC immunization to mimic the onset of illness, examined the effects of 8 and 4 days of E. purpurea treatment at 0.6 mL/kg/day. Only in the 4-day administration, with dosing beginning 1 hour after SRBC immunization, was there an observed enhancement of the antibody forming cell response. This supports the acute use of E. purpurea as suggested by anecdotal reports, and demonstrates the potential for enhancement of humoral immune responses as well as innate immune responses.

J Pharm Biomed Anal. 2003 Nov 24;33(4):845-50.

Trace elements analysis of Echinacea purpurea--herbal medicinal.

Razic S, Onjia A, Potkonjak B. Faculty of Pharmacy, University of Belgrade, Belgrade, Yugoslavia.

Elemental composition of Echinacea purpurea (Asteracae), grown in Serbia under strongly controlled conditions, has been studied. To distinguish elemental patterns of different parts of the plant, the content of Zn, Fe, Cu, Mn, Ca, Mg, Sr, Ni, and Li in root versus upper plant parts were determined, by flame atomic absorption and flame atomic emission spectrometry. Analyses of the mentioned elements in soil and in an ethanolic extract of E. purpurea were made, too. The trace element data were evaluated by multivariate methods, i.e. principal component analysis and hierarchical cluster analysis. This revealed two groups of elements (I: Fe, Cu, Mn, Li; II: Ca, Mg, Zn, Ni), while trace element profiles of root, stem, leaves, and flowers of this plant differed significantly. However, no significant difference in the trace element patterns between the summer and the autumn harvest samples was found.

J Agric Food Chem. 2003 Nov 19;51(24):6922-33.

A reversed-phase high-performance liquid chromatography (HPLC) method has been developed to determine caffeic acid derivatives, for example, cichoric acid, and alkamides in plant parts and herbal products of Echinacea purpurea. The method consists of an extraction procedure whereby the hydrophilic phenolics as well as the lipophilic alkamides are released from the samples, followed by the analytical HPLC procedure for quantitative determination of these compounds. The method is the first one validated for the determination of these two groups of compounds in the same procedure. Naringenin has been used as an internal standard, as no other flavanones are present in the extract and it does not interfere with any of the compounds under investigation. Analysis of Danish-grown plant material shows that it is possible to raise plants of a very high chemical quality in Denmark . A selection of international herbal products available on the Danish market show surprisingly variable quality, not necessarily reflecting the product information given on the labels.

Exp Biol Med ( Maywood ). 2003 Oct;228(9):1051-6.

Regulation of human immune gene expression as influenced by a commercial blended Echinacea product: preliminary studies.

Randolph RK, Gellenbeck K, Stonebrook K. Nutrilite Health Institute, Access Business Group, LLC, Buena Park , California , USA .

Consumption of Echinacea at the first sign of symptoms has been clinically shown to reduce both the severity and duration of cold and flu. Quantitative polymerase chain reaction optimized for precision and reproducibility was utilized to explore in vitro and in vivo changes in the expression of immunomodulatory genes in response to Echinacea. In vitro exposure of THP-1 cells to 250 microg/ml of Echinacea species extracts induced expression (up to 10-fold) of the interleukin-1alpha, interleukin-1beta, tumor necrosis factor-alpha, intracellular adhesion molecule, interleukin-8, and interleukin-10 genes. This preliminary result is consistent with a general immune response and activation of the nonspecific immune response cytokines. In vivo gene expression within peripheral leukocytes was evaluated in six healthy nonsmoking subjects (18-65 years of age). Blood samples were obtained at baseline and on Days 2, 3, 5, and 12 after consuming a commercial blended Echinacea product, three tablets three times daily (1518 mg/day) for two days plus one additional dose (506 mg) on day three. Serum chemistry and hematological values were not different from baseline, suggesting that liver or bone marrow responses were not involved in acute responses to Echinacea. The overall gene expression pattern at 48 hr to 12 days after taking Echinacea was consistent with an antiinflammatory response. The expression of interleukin-1beta, tumor necrosis factor-alpha, intracellular adhesion molecule, and interleukin-8 was modestly decreased up through Day 5, returning to baseline by day 12. The expression of interferon-alpha steadily rose through Day 12, consistent with an antiviral response. These preliminary data present a gene expression response pattern that is consistent with Echinacea's reported ability to reduce both the duration and intensity of cold and flu symptoms.

Publication Types:

•  Clinical Trial

Pol J Vet Sci. 2003;6(3 Suppl):3-5.

Echinacea purpurea stimulates cellular immunity and anti-bacterial defence independently of the strain of mice.

Bany J. Department of Pharmacology and Toxicology, Military Institute of Hygiene and Epidemiology, Warsaw , Poland .

One of the major functions of the immune system is anti-bacterial defence mediated among others by non-specific immunity (macrophages, granulocytes). Echinacea purpurea extracts are widely used in prophylaxis and therapy of various infections, mainly the respiratory tract, in animals and humans. The aim of this work was to evaluate the effect of prophylactic use of Echinacea purpurea extract on the development of Pseudomonas aeruginosa infection in various strains of mice and on some parameters of non-specific and also specific cellular immunity. Mice expressed various, depending on the strain used, susceptibility to infection. Echinacea feeding resulted in diminishing of bacteria number in livers of C57Bl/6 (susceptible strain) as well as B6C3F1 (relative resistant strain) mice. Echinacea feeding of the second relative resistant strain (BALB/c x C3H) F1 resulted in stimulation of granulocytes chemiluminescent and lymphocytes proliferative response.

Medicina ( Kaunas ). 2003;39(8):761-6.

Effect of Echinacea (Echinacea Purpurea L. Moench) preparations on experimental prostate gland.

Skaudickas D, Kondrotas AJ, Baltrusaitis K. Department of Physiology, Kaunas University of Medicine, 3000 Kaunas, Lithuania.

Planta Med. 2003 Jul;69(7):685-6.

Genetic characterization of the three medicinal Echinacea species using RAPD analysis.

Nieri P, Adinolfi B, Morelli I, Breschi MC, Simoni G, Martinotti E.

The three medicinal species of the Echinacea genus, E. angustifolia DC., E. pallida (Nutt.) Nutt. and E. purpurea (L.) Moench were distinguished using the RAPD (random amplified polymorphic DNA) technique. Species-specific markers were identified from amplicons obtained with four of the twenty 10-mer primers contained in the Operon RAPD kit A. In particular, one marker was identified for E. angustifolia (OPA 20, 1800 pb) and E. pallida (OPA 10, 600 pb) and three markers for E. purpurea (OPA 11 : 1250 pb; OPA 17 : 750, 1800 pb). Genetic distance analysis indicated a high degree of difference among the three species with a relative lower difference between E. angustifolia and E. pallida.

Publication Types:

•  Letter

Parasitol Res. 2003 Sep;91(1):74-8. Epub 2003 Jul 29.

Dietary supplementation with Echinacea and development of immunity to challenge infection with coccidia.

Allen PC. Animal and Natural Resources Institute, Parasite Biology Epidemiology and Systematics Laboratory, USDA-ARS, Beltsville , MD 20705 , USA .

An experiment was conducted to examine the effects of dietary supplementation with 0.1% and 0.5% ground root preparations of Echinacea purpurea (EP; common name: purple cone flower) on the development of immunity following live vaccination and subsequent challenge with multiple coccidia species in an experimental model using a commercial live vaccine preparation. Effects of immunization and EP supplementation on weight gains before challenge, and weight gains, lesion scores and plasma levels of carotenoids and NO2-+NO3- following challenge were determined. In this experiment, combined live vaccination and feed supplementation with 0.1% or 0.5% EP during the first 2 weeks of life provided significant weight gain advantage compared to live vaccination alone. This advantage persisted through 2 weeks of EP withdrawal and subsequent challenge infection. EP supplementation also significantly lowered total lesion scores but did not significantly modify the effects of vaccination and challenge on plasma carotenoids or NO2-+NO3-.

Pharmacol Res. 2003 Sep;48(3):273-7.

Apoptosis, or programmed cell death (PCD), is a physiological active cellular suicide process that occurs in non-contiguous cells, and is usually not associated with inflammation. The apoptotic process can be modulated by various stimuli, including hormones, cytokines, growth factors, and some chemotherapeutic agents. To determine whether Echinacea purpurea and Hypericum perforatum are able to regulate the process of apoptosis in vivo and to define the role of the Fas-Ag and Bcl-2 signal transduction cascade, we have orally treated groups of mice with these vegetable drugs for 14 days. The splenic lymphocytes from mice treated with E. purpurea and H. perforatum at the two dose levels used (30 and 100 mg kg(-1) per day) were shown to be significantly more resistant to apoptosis than those from mice treated only with the vehicle. In addition, mice treated with the natural substances showed a decrease in Fas-Ag expression and an increase in Bcl-2 expression. In conclusion, our results shown that in vivo the studied drugs modulate apoptosis in mice splenic lymphocytes and that this action could be mediated in part by a decrease in Fas-Ag expression and in part by an increase in Bcl-2 expression.

Int Immunopharmacol. 2003 Jul;3(7):1041-8.

Echinacea is one of the most widely used over-the-counter herbal preparations that purport to "improve immune system function", especially when taken as a short course of therapy (6-8 weeks). Since many purchasers are older individuals, a double-blind, placebo-controlled study was performed to investigate whether Echinacea could affect total and differential white cell counts, phagocytic activity and interleukin (IL-2) levels in 12-month-old, healthy, male Sprague-Dawley rats when administered over an 8-week period. Echinacea (50 mg/kg of aerial parts) mixed with peanut butter or peanut butter alone was fed to 16 rats, which were receiving regular food and water ad libitum. Cell counts and immune functions were determined on rat tail vein blood on a weekly basis. Echinacea significantly increased circulating total white cell counts during the first 2 weeks of administration, and IL-2 levels during the final 5 weeks of the study period (p<0.05). Differential counts were altered during the entire 8-week study, with mononuclear cells significantly increased to the detriment of granulocytes (p<0.05). No such changes were observed in animals given peanut butter alone. No difference was observed in phagocytic function between animals given Echinacea or peanut butter alone. These studies suggest that aerial components of Echinacea affect both mononuclear cell levels and circulating IL-2 levels in older animals.

Forsch Komplementarmed Klass Naturheilkd. 2003 Apr;10 Suppl 1:9

[History of a plant: the example of Echinacea]

Hostettmann K. Institut de Pharmacognosie et Phytochimie, Universit de Lausanne , Switzerland .

In comparison with other medicinal plants, the history of use of Echinacea is relatively short. The plant originates from North America and was employed by the indigenous Indians. The first archaeological evidence dates from the 18th century. Included in the name Echinacea or purple coneflower are several species of the Asteraceae family: Echinacea purpurea (L.) Moench, Echinacea angustifolia DC. and Echinacea pallida (Nutt.) Nutt. Information about the use of the plant from traditional healers ranges from external application for wounds, burns and insect bites to the chewing of roots for toothache and throat infections, and internal application for pain, coughs, stomach cramps and snake bites. The interest of white settlers was also drawn to this medicinal plant. The first Echinacea preparation, known as Meyers Blood Purifier, arrived on the market around 1880, with rheumatism, neuralgia and rattlesnake bites as indications. At the beginning of the 20th century, Echinacea was the most frequently used plant preparation in the USA . Commercial cultivation was started in Germany around 1939. The introduction and cultivation of Echinacea in Switzerland by A. Vogel was around 1950. Chemists and pharmacologists became interested in Echinacea and many constituents are now known, such as polysaccharides, echinacoside, cichoric acid, ketoalkenes and alkylamides. The extracts exhibit immunostimulant properties and are mainly used in the prophylaxis and therapy of colds, flu and septic complaints. Although there are over 400 publications concerning the plant and dozens of preparations of Echinacea n the market, the true identity of the active principles still remains open. Copyright 2003 S. Karger GmbH, Freiburg

Publication Types:

•  Historical Article

Schweiz Arch Tierheilkd. 2003 May;145(5):223-31.

Echinacea powder: treatment for canine chronic and seasonal upper respiratory tract infections.

Reichling J. Institut fur Pharmazie und Molekulare Biotechnologie, Ruprecht-Karls-University, Heidelberg , Germany .

An open multi-centered veterinary clinical trial, comparing conditions before and after treatment with a herbal preparation, containing the powdered root of Echinacea purpurea, was conducted by 6 practicing veterinarians in Switzerland . The plant-based immune stimulant was administered to 41 dogs with manifestations of chronic and seasonal upper respiratory tract infections, including pharyngitis/tonsillitis, bronchitis and kennel cough. Each animal was at an individual stage of the disease, with various symptoms and different severity scores, at start of treatment. There was no control group. Echinacea powder (1:3) was administered with the food at a dose of 1.0 g/10 kg body weight once daily for 8 weeks. Overall efficacy showed significant improvement for 92% of 39 dogs after 4 weeks of treatment and this was confirmed after 8 weeks. Significant reductions of severity and resolution of typical clinical symptoms, of clear nasal secretions, enlargement of lymph nodes, dry cough, dyspnea and dry lung sounds, were evident after 4 weeks. Only two adverse effects, not suspected to be attributable to the study drug, were recorded. Because quality and stability of the Echinacea powder were defined, using an analytical standard and purity tests, these data suggest, that the Echinacea preparation can be recommended as a well tolerated alternative treatment of canine upper respiratory tract infections.

Publication Types: Clinical Trial, Multicenter Study

Int Immunopharmacol. 2003 Jun;3(6):811-24.

Echinacea purpurea, a plant originally used by native Americans to treat respiratory infections, has also been shown to exert immunomodulatory activities both in vivo and in vitro. However, the mechanism underlying Echinacea-induced immunomodulation remains largely unknown. This study examined in vitro the effects of soluble extracts of E. purpurea on natural killer (NK) cells present in human peripheral blood mononuclear cells (PBMC). Flow cytometric methods were used to examine activation, cytotoxicity, NK-target binding, and killer cell frequency. Treatment of PBMC with Echinacea overnight resulted in the activation of CD69 expression and increase in mean fluorescence intensity in both the CD16+ and CD16+CD56+ NK subsets. However, the frequency of CD16+ cells was decreased as well as the mean fluorescence intensity was down-regulated. NK cytotoxicity was augmented 100% at the concentration of 0.1 microg/ml of Echinacea in a short time (4-h) assay. Examination at the single cell level revealed augmentation of the frequency of CD56+ NK-target conjugates and a plateau was reached after 30-60 min of incubation. Likewise, the frequency of CD56+ killer cells in the conjugates was also significantly increased by Echinacea. There was recruitment of non-conjugated CD56+ cells into CD16+ NK-target conjugates and activation of the NK-target non-killer conjugates into killer cells. These findings demonstrate that Echinacea extracts are potent activators of NK cytotoxicity. Echinacea augments the frequency of NK target conjugates and activates the programming for lysis of NK cells.

Zhongguo Zhong Yao Za Zhi. 2002 Jun;27(6):418-20.

[Determination of cichoric acid in Echinacea purpuea]

Wang H. School of Pharmaceutical Sciences, Peking University , Beijing 100083, China .

OBJECTIVE: To analyze the natural change rule of active components of E. purpuea by measuring content of cichoric acid. METHOD: Reverse HPLC method was used. RESULT: The maximum cichoric acid content of the roots occured in seedling age of May, and that of the flowers occured in blooming stage of mid July, but cichoric acid in stems was generally low anyway. The maximum content of cichoric acid in the plant above ground occured in the blooming stage of mid July. CONCLUSION: The measuring method of content of cichoric acid is successful and reliable. The optimum stage of harvest in Echinacea purpuea should be guided by natural change rule of cichoric acid content.

Zhongguo Zhong Yao Za Zhi. 2002 Jan;27(1):40-2.

J AOAC Int. 2003 Mar-Apr;86(2):202-8.

Analytical methodologies with ultrasonic extraction and liquid chromatography (LC) were developed for the determination of phenolic compounds in dietary supplements containing Echinacea. The phenolic compounds determined by these methods included caftaric acid, chlorogenic acid, cynarin, echinacoside, and cichoric acid. Samples from tablets, capsules, and bags of tea blends were extracted by sonication for < or = 30 min with methanol-water (60 + 40). The extracts were centrifuged and filtered, and the filtrates were diluted and analyzed by LC using a reversed-phase column and coulometric electrochemical (EC) detection. The mobile phase was acetonitrile-ammonium formate buffer, pH 3.5 (15.3 + 84.7) containing tetrabutyl ammonium hydrogen sulfate as an ion-pairing reagent. Extraction conditions (e.g., composition of the extraction solvent and sonication time) were optimized for different types of samples. Intra- and interday analytical variations were determined, and intraday analyses were performed by 2 independent analysts using 2 different LC systems. Results were generally comparable. The LC method with EC detection showed better sensitivity and selectivity when compared with LC with ultraviolet detection, although results were similar for the 2 methods for major compounds, i.e., caftaric acid, echinacoside, and cichoric acid. The identities of these major compounds found in samples were confirmed by LC/electrospray ionization mass spectrometry.

J Agric Food Chem. 2003 Mar 12;51(6):1608-10.

Root and aerial sections (flower, stem, and leaf) of Echinacea purpurea were dried with hot air at temperatures in the range of 40-70 degrees C, and the concentrations of alkylamides and cichoric acid were determined after drying. Increasing drying temperature decreased from 48 h at 40 degrees C to 9 h at 70 degrees C but resulted in a decreased concentration of cichoric acid in all plant sections with a greater loss from aerial plant parts than from the root. There was, however, no significant difference in the concentration of the alkylamides at any drying temperature. Establishment of operational parameters for the drying of echinacea must therefore be structured around the more labile cichoric acid.

J Chromatogr A. 2003 Jan 31;986(1):73-81.

High-performance liquid chromatography (HPLC) coupled with UV photodiode-array detection and electrospray ionization mass spectrometry was developed for the simultaneous analysis of caffeic acid derivatives and alkamides in the roots and extracts of Echinacea purpurea. Caffeic acid derivatives and alkamides produced very abundant peaks in the total ion current chromatogram during negative and positive cone voltage switching. Cichoric acid and the isomer pair, dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamide, were used as a standard for quantification of caffeic acid derivatives and alkamides in E. purpurea. This novel method surpasses previously published ones in product quality control and providing the HPLC chromatographic fingerprints of biological active components in E. purpurea.

Theor Appl Genet. 2002 Aug;105(2-3):369-376. Epub 2002 Jun 19.

The genus Echinacea is comprised of nine species, which are perennial herbs indigenous to North America and which have been traditionally used as medicinal plants for centuries. Three Echinacea species, E. angustifolia, E. purpurea, and E. pallida, are currently being traded internationally in the natural products market. Echinacea products constitute a significant portion of this growing, multi-billion dollar industry. The increasing popularity of Echinacea products has led to the expansion of wildcrafting and commercial cultivation to meet the growing demand for plant material. Echinacea is considered of value as a nonspecific immune stimulant, and claims of its efficacy have been tentatively supported by both laboratory and clinical studies. This study used random amplified polymorphic DNA (RAPD) markers to determine the genetic relationships of the three Echinacea species of commercial interest, to evaluate the level of diversity present within germplasm of each of the three species, and to compare accessions of each species available from different sources. A total of 101 RAPD markers were generated for the 76 individuals of four species included in the analysis. NTSYS-pc was used to evaluate the genetic relationships of the three species and to determine the general level of overall diversity. Analysis of molecular variance (AMOVA) was performed using pruned marker sets corrected for the dominant nature of RAPD markers. AMOVA revealed that most of the variation occurred within accessions of the same species, though some accessions of both E. pallida and E. angustifolia were found to be significantly different from other accessions of the same species.

Yao Xue Xue Bao. 2002 Feb;37(2):121-3.

Am Fam Physician. 2003 Jan 1;67(1):77-80.

Echinacea.

Kligler B. Department of Family Medicine, Albert Einstein College of Medicine, New York , New York , USA .

Echinacea is the name of a genus of native North American plants, commonly known as the purple coneflower. The most widely used herbal product in the United States is a liquid extract made from the root of Echinacea purpurea. Because the active component of the plant has not been identified, commercial echinacea products are not typically standardized to any particular component. The research literature on echinacea is difficult to evaluate because of the heterogeneity of the products used in various studies. The herb has been recommended as a prophylactic treatment for upper respiratory infection and is widely used for this indication. However, based on the current literature, it appears that prophylactic echinacea does not have a significant impact on the frequency, severity, or duration of upper respiratory infection. The data regarding treatment of upper respiratory infection appear to support a modest positive effect. No significant herb-drug interactions with echinacea have been reported; adverse effects reported generally have been uncommon and minor, including abdominal upset, nausea, and dizziness.

Planta Med. 2002 Dec;68(12):1118-24.

Differentiation between the complement modulating effects of an arabinogalactan-protein from Echinacea purpurea and heparin.

Alban S. Institute of Pharmacy, University of Regensburg , Regensburg , Germany .

Due to the important physiological role of the complement system, complement modulation, either inhibition or stimulation, is an interesting target for drug development. Several plant polysaccharides are known to exhibit complement modulating activities. Sometimes these effects are described as complement inhibition, although the basic mechanism is a stimulation of the complement activation. This misinterpretation is due to the observed reduced haemolysis in the widely used haemolytic complement assay, which does not allow to differentiate between complement activators and inhibitors, when it is performed in the classical manner. The aim of the presented study was to demonstrate that by simple modifications of the classical procedure this assay becomes an efficient tool to distinguish between real complement inhibitors and complement activating compounds without performing expensive, molecular mechanistic investigations. As practical examples heparin with proven complement inhibiting activity and AGP, a new arabinogalacatan-protein type II isolated from pressed juice of the aerial parts of Echinacea purpurea, as a potential complement activating compound were included in the study. By means of varying the preincubation time of the test compound with complement, AGP was clearly identified as a stimulator of both the classical and alternative pathway of complement activation. These findings correspond to the results of molecular mechanistic investigations. Selective removal of the arabinose side chains of AGP resulted in considerably reduced activity. Therefore, the three-dimensional structure of the polysaccharide, i. e., a backbone branched by side chains, is supposed to be important for the interactions with the complement system. The complement activating effects of AGP may contribute to the well-established immunostimulating effects of the pressed juice from Echinacea purpurea. Abbreviations. AGP:arabinogalactan-protein AGP-hydr.:hydrolysed arabinogalactan-protein AP-CA:haemolytic complement assay for the alternative pathway CP-CA:haemolytic complement assay for the classical pathway EGTA-VB:veronal buffered saline containing EGTA and Mg 2+HPS:human pooled serum RT:room temperature LPS:lipopolysaccharide RaE:rabbit erythrocytes RT:room temperature ShE(A):(sensitised) sheep erythrocytes VB:veronal buffered saline containing Ca 2+ and Mg 2+

J Pharm Pharmacol. 2002 Oct;54(10):1379-83.

Echinacea purpurea (L.) Moench and Hypericum perforatum (L.) were evaluated for their anti-inflammatory activity against carrageenan-induced paw oedema in mice. Each drug was administered orally to mice at 30 and 100 mg kg(-1), twice daily. Only the higher dose significantly inhibited, time dependently, the formation of oedema, evaluated as area under the curve (echinacea P < 0.01; hypericum P < 0.05). Western blot analysis showed that in-vivo treatment with these extracts could modulate lipopolysaccharide (LPS) and interferon-gamma induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression in peritoneal macrophages. In particular, treatment with 100 mg kg(-1) hypericum inhibited both iNOS and COX-2 expression, whereas treatment with 100 mg kg(-1) echinacea down-regulated only COX-2 expression. The present study suggests that the anti-inflammatory effect of these extracts could be in part related to their modulation of COX-2 expression.

Planta Med. 2002 Oct;68(10):926-9.

Rapid and non-destructive determination of the echinacoside content in Echinacea roots by ATR-IR and NIR spectroscopy.

Schulz H. Federal Centre for Breeding Research on Cultivated Plants, Institute for Plant Analysis, Quedlinburg , Germany .

NIR reflection and ATR-IR spectroscopy methods are developed to determine the echinacoside content in roots of Echinacea angustifolia and Echinacea pallida. Based on the recorded spectra and the HPLC reference data, chemometrical analyses are performed using a partial least squares (PLS) algorithm. Generally, good calibration statistics are obtained for the prediction of the echinacoside content presenting comparatively high coefficients of determination (R(2)) and low root mean standard errors of cross validation (RMSECV). It is demonstrated that optimal predictions are possible when using a dispersive spectrometer covering the spectral range from 1,100 to 2,500 nm. In contrast to the time-consuming HPLC method, the described non-destructive measurements allow us to predict the echinacoside content already after an analysis time of approx. one minute. Both spectroscopic techniques presented in this paper are shown to be useful in agricultural practice as well as in the phytopharmaceutical industry.

Publication Types:

•  Evaluation Studies

Planta Med. 2002 Sep;68(9):780-3.

Extracts of 8 taxa of the genus Echinacea were found to have antiviral activity against Herpes simplex (HSV) virus Type I in vitro when exposed to visible and UV-A light. n-Hexane extracts of roots containing alkenes and amides were more active in general than ethyl acetate extracts containing caffeic acids. The most potent inhibitors of HSV were E. pallida var. sanguinea crude (70 % ethanol) inflorescence extract (MIC = 0.026 mg/mL), cichoric acid (MIC = 0.045 mg/mL) and Echinacea purpurea n-hexane root extract (MIC = 0.12 mg/mL).

Wien Med Wochenschr. 2002;152(15-16):407-11.

[New knowledge regarding the effect and effectiveness of Echinacea purpurea extracts]

Bauer R. Institut fur Pharmakognosie, Karl-Franzens-Universitat, Universitatsplatz 4, Graz .

Preparations made from the pressed juice of the flowering aerial parts of the Purple Coneflower, Echinacea purpurea (L.) Moench represent the most commonly used herbal immunnomodulatory agents. They are frequently administered for the supportive treatment of common viral infections of the upper respiratory tract. New clinical studies are reviewed, which demonstrated that corresponding preparations can diminish the severity and the length of common colds significantly, and that they can also be used efficiently for the treatment of children. New investigations have also shown, that stimulation of makrophages and induction of cytokins are major parts of the mode of action, and that glycoproteins/polysaccharides and alkamides are part of the activity relevant constituents.

Publication Types:

•  Review

•  Review, Tutorial

Chem Res Toxicol. 2002 Sep;15(9):1174-8.

In response to concerns that commercial dietary supplements containing Ginkgo biloba (ginkgo) and Echinacea purpurea, Echinacea angustifolia, or Echinacea pallida (echinacea) might be contaminated with colchicine, a highly selective and sensitive assay was developed for colchicine that is based on high-performance liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method utilizes reversed-phase HPLC separation of compounds in a methanolic extract of the dietary supplement or botanical sample followed by positive ion electrospray ionization with collision-induced dissociation and multiple reaction monitoring of three characteristic fragmentation pathways of the protonated molecule of colchicine, m/z 400 --> 358, 400 --> 326, and 400 --> 310. The minimal detectable concentration of colchicine using this assay was 10 pg on-column, which is equivalent to 20 ppb colchicine in a 0.5 g ginkgo leaf sample. The method was validated by analyzing 0.5 g samples spiked with colchicine and determining the recovery. A total of 26 commercial ginkgo and echinacea dietary supplements were purchased from pharmacies in Chicago , IL , and analyzed for colchicine. In contrast to a recent report, no colchicine was detected in any of the samples. In addition, authenticated ginkgo leaves were collected, assayed, and found to contain no colchicine, which is consistent with the botanical literature. On the basis of the results obtained using this new LC-MS-MS assay, which is more sensitive and more selective than previously published methods for colchicine, we find no cause for concern regarding colchicine contamination of ginkgo or echinacea dietary supplements.

Phytomedicine. 2002 Jul;9(5):390-7.

A phytopharmaceutical containing an extract of Echinacea purpurea and Glycyrrhiza glabra root (Revitonil tablets) was investigated for its suggested immunostimulating potential, using several in vitro tests and the in vivo carbon-clearance model in mice. In the in vitro phagocytosis test with human granulocytes, Revitonil showed a 44-53% stimulating effect at a concentration of 100 microg/ml. Whereas in the chemoluminescence test at a concentration of 1.25 microg/ml, Revitonil tablets exhibited a moderate enhancing effect only, a remarkable stimulating activity (30-50%) was observed in the T-lymphocyte CD69 bioassay at a concentration of 100 microg-1 microg/ml. The highest immunological efficacy could be assigned to Revitonil as revealed by the in vivo carbon-clearance model in mice. With RCt/RCc-values of 2.0, Revitonil exhibited a very high carbon elimination rate at oral administration. Because the Echinacea and Glycyrrhiza monoextracts alone showed lower RCt/RCc-values (1.3-1.7) than Revitonil, a potentiating synergistic effect of the extract mixture in Revitonil can be postulated.

Electrophoresis. 2002 Sep;23(17):3084-92.

Separation of alkamides from Echinacea purpurea extracts by cyclodextrin-modified micellar electrokinetic chromatography.

Gotti R, Fiori J, Hudaib M. Dipartimento di Scienze Farmaceutiche, Universita di Bologna, Bologna, Italy.

Separation of nine important alkyl methylbutyl- and isobutylamides (known as alkamides) obtained from Echinacea purpurea extracts was investigated by using cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC). Hydrophobic alkamides interact strongly with the micelles from the most common surfactants used in MEKC and this lead to predominant partition of the analytes into the micellar phase, resulting in poor resolution. The addition of neutral CDs to the alkaline ( 10 mM phosphate buffer pH 8.0) micellar system of sodium dodecyl sulfate (SDS), sodium cholate (SC) and sodium deoxycholate (SDC) was found to improve the separation of the studied alkamides. Among the several combinations surfactant/CD, three different systems showed to be particularly effective: SDS/hydroxypropyl-beta-CD (110 mM/100 mM) and SC/heptakis (2, 3, 6-tri-O-methyl)-beta-CD (200 mM/40 mM) which provided a complete separation of the studied compounds, and SDC/heptakis (2, 6-di-O-methyl)-beta-CD. The importance of appropriate surfactant vs. CD concentration ratio as well as that of total concentration of both surfactant and CD was considered. The optimization of the separation was performed by focussing the need for a rapid separation of nine alkamides diagnostically useful to define the fingerprint of Echinacea species.

J Nutr Biochem. 2002 Aug;13(8):487.

Echinacea plant extract has been used for immunostimulation for many years but the evidence supporting its therapeutic potential is still controversial. Using male Sprague-Dawley rats (425- 475 g ), an in vivo study was conducted to examine the immunomodulatory effects of preparations of Echinacea containing its components cichoric acid, polysaccharides and alkylamides in different concentrations. The rats were gavaged orally with these preparations, two times/day for 4 days. Phagocytic activity of alveolar macrophage was increased with increasing concentrations of the Echinacea components. A trend of increase in TNF-alpha and nitric oxide release by the alveolar macrophages following an in vitro stimulation with LPS was also evident. An enhanced release of cytokines (such as TNF-alpha and IFN-gamma) in response to Echinacea components, was also apparent in rat's spleen macrophage, but at higher concentrations. These results suggest that the Echinacea preparations containing optimal concentrations of cichoric acid, polysaccharides and alkylamides are potentially effective in stimulating an in vivo, non-specific immune response in normal rats.

Equine Vet J. 2002 May;34(3):222-7.

Immunological and haematinic consequences of feeding a standardised Echinacea (Echinacea angustifolia) extract to healthy horses.

O'Neill W. Equine Research Centre, Guelph , Ontario , Canada .

This study was undertaken to compile new data on the efficacy of Echinacea in stimulating the immune system of the horse. Use of Echinacea is becoming widespread in horses, despite an absence of controlled laboratory research into its effectiveness or safety. This paper documents results of a double-blind, placebo-controlled, cross-over trial investigating the effect of standardised Echinacea extract on 8 horses. Animals were supplemented with Echinacea or placebo for 42 days, and their response to supplements recorded. Treatment with Echinacea increased phagocytic ability of isolated neutrophils, boosted peripheral lymphocyte counts and appeared to stimulate neutrophil migration from peripheral circulation into the tissues. Echinacea supplement also increased the size and concentration of peripheral red blood cells, and the concentration of haemoglobin and packed cell volume. It was concluded that Echinacea effectively stimulates equine immunocompetence, and the plant extract behaves, in equine subjects, as a haematinic agent, i.e. one which improves the quality of blood by increasing haemoglobin levels and the number of erythrocytes and which, by virtue of their effects on oxygen transport cells, are considered to improve parameters of exercise physiology and performance.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Planta Med. 2002 Jun;68(6):572-4.

Simultaneous analysis of alkamides and caffeic acid derivatives for the identification of Echinacea purpurea, Echinacea angustifolia, Echinacea pallida and Parthenium integrifolium roots.

Laasonen M, Wennberg T, Harmia-Pulkkinen T, Vuorela H.

A reversed-phase HPLC method was developed using a computer simulation program for the identification of dried roots of Echinacea purpurea, E. angustifolia, E. pallida and Parthenium integrifolium. Hydrophilic and lipophilic compounds were analysed simultaneously leading to a two-fold decrease in analysis time compared to traditional HPLC methods.

Publication Types:

•  Letter

J Agric Food Chem. 2002 Jul 3;50(14):3967-70.

Stabilization of caffeic acid derivatives in Echinacea purpurea L. glycerin extract.

Bergeron C, Gafner S, Batcha LL. Tom's of Maine, Lafayette Center, Kennebunk, Maine, USA.

Recent work has shown that enzymatic degradation and oxidation of cichoric acid and other caffeic derivatives occurs in Echinacea preparations. However, very little is known as to the means of stabilizing these phytopreparations. To stabilize the glycerin extract of Echinacea purpurea, we have evaluated the effects of 3 natural antioxidants (citric acid, malic acid, and hibiscus extract) on the stability of the major caffeic acid derivatives (caftaric acid, caffeic acid, cichoric acid, and 2-O-feruloyl-tartaric acid). Chlorogenic acid, which normally occurs in an ethanol extract of E. purpurea, was not present in the glycerin extract. The caffeic acid derivatives, with the exception of 2-O-feruloyl-tartaric acid, were subject to degradation in the control sample. 2-O-Feruloyl-tartaric acid was stable during the whole testing period. All antioxidant treatments greatly improved the stability of caffeic acid derivatives. Stability was dependent upon the concentration of antioxidant added.

J Agric Food Chem. 2002 Jul 3;50(14):3947-53.

Echinacea has been known for its immunostimulatory activity, and its alkylamide components have been linked to such biological activity. Consequently, alkylamides in Echinacea angustifolia were extracted using supercritical carbon dioxide from fresh and dried roots at 45-60 degrees C and 34-55 MPa, and the alkylamide yield in the extracts was determined. The yield of alkylamides from fresh roots increased with temperature yet decreased with pressure, whereas the yield from air-dried roots (moisture content 8.4%) increased with both temperature and pressure. Freeze-drying of the roots to a moisture content of 4.9% did not result in any further increase in the yield compared to that of air-dried roots. Alkylamide yield of the ground dried roots extract was the highest (p < or = 0.05) among those from fresh, ground and unground E. angustifolia roots. Supercritical fluid extraction therefore shows potential for the recovery of alkylamides from dried Echinacea roots.

Anal Chem. 2002 Jun 1;74(11):2493-9.

Near-infrared (NIR) reflectance spectroscopy was used to develop a fast identification method for Echinacea purpurea dried milled roots. Method development was carried out using a PLS (partial least-squares) algorithm and pretreatment options. The aim of this qualitative analysis was to confirm the identity of E. purpurea and to detect the presence of fraud, i.e., samples adulterated or substituted by Echinacea angustifolia, Echinacea pallida, or Parthenium integrifolium. Specificity was demonstrated by testing a validation set against the method. A total of 10% of the E. purpurea batches (true samples) and 0% of the false samples from that validation set were misidentified by the method. The misidentification was due to the difference in particle size distribution of one E. purpurea batch compared to that of the other samples. Adulterated E. purpurea samples can be detected at a minimum of 10% of adulteration. This study demonstrates that NIR spectroscopy is a good tool for the fast identification of E. purpurea roots if the samples are milled using the same procedure as for the calibration samples. The method is robust with respect to the origin of the samples and can be used routinely by the pharmaceutical industry or herbal suppliers to avoid mislabeling errors or adulteration.

J Agric Food Chem. 2002 Jun 19;50(13):3673-87.

Phytochemical variation in echinacea from roots and flowerheads of wild and cultivated populations.

Binns SE. Biology Department, University of Ottawa , P.O. Box 450 Station A, Ontario , Canada

Quantitative phytochemical variation was determined from roots and inflorescences of native plant populations in the genus Echinacea. Specimens were collected in situ throughout the natural range of each putative taxon and transplanted to greenhouse cultivation. Ethanolic extracts from individual plants were separated by reversed-phase HPLC to quantify the alkamides, polyenes/ynes, and phenolics, and then grouped by age and taxonomically, according to a recent morphometric taxonomic revision of the genus. Canonical discriminant analysis revealed that cichoric acid, the diene alkamides 1-3 and 7, and ketoalkene 24 were the best taxonomic markers. Mean content for each of 26 phytochemicals revealed useful agronomic information, such as those varieties and organs with the highest accumulations, as well as the optimal age and growth conditions for each variety. The highest amounts of cichoric acid were measured from the older, wild inflorescences of E. pallida var.sanguinea, whereas the highest quantities of the alkamides 1-3 and 7 were present in roots of wild and transplanted E. purpurea. Baseline phytochemical data and chromatographic profiles for all types of wild Echinacea may be used for protection of wild stands, germplasm identification, and crop improvement.

Planta Med. 2002 May;68(5):469-71.

Transport of alkamides from Echinacea species through Caco-2 monolayers.

Jager H, Meinel L, Dietz B, Lapke C, Bauer R, Merkle HP.

To gain more insights into the human intestinal absorption of alkamides from Echinacea species, transport studies were performed with the human adenocarcinoma colonic cell line Caco-2 (ATCC) as a model to assess the epithelial transport of dodeca-2 E,4 E,8 Z,10 E/ Z-tetraenoic acid isobutylamides (1/ 2). 30 minutes after apical loading of 25 microg/ml 1/ 2, about 15 % of these alkamides were detectable on the basolateral side. Close monitoring of the transport during 6 hours revealed a nearly complete transport to the basolateral side after 4 hours and no significant metabolism was observable. Transport experiments performed at 4 degrees C showed only a slight decrease in transport, which is a strong hint that dodeca-2 E,4 E,8 Z,10 E/ Z-tetraenoic acid isobutylamides (1/ 2) cross biological membranes by passive diffusion. Nearly the same results were obtained after preincubation of the Caco-2 cells with lipopolysaccharides (LPS) or phorbol 12-myristate-13-acetate (PMA) to mimic an inflammatory status. These results support the assumption that the alkamides can be easily transported from the intestinum and hence may contribute to the in vivo effects of Echinacea preparations.

Publication Types:

•  Letter

Phytomedicine. 2002 Apr;9(3):249-53.

Alkamides from the roots of Echinacea purpurea (L.) Moench were examined for anti-inflammatory activity in an in vitro model system. Cyclooxygenase-I (COX-I) and cyclooxygenase-II (COX-II) inhibitory activities were assessed at pH 7 for alkamides isolated from E. purpurea roots to compare inhibitory activities between the two cyclooxygenase isozymes. At 100 microg/ml, several E. purpurea alkamides inhibited COX-I and COX-II enzymes in the range of 36-60% and 15-46%, respectively, as compared to controls. Mosquitocidal activity was assessed at 100 and 10 microg/ml, with 100% mortality against Aedes aegyptii L. larvae noted for several E. purpurea alkamides at 100 microg/ml.

Altern Med Rev. 2002 Apr;7(2):138-49.

Immunological activity of larch arabinogalactan and Echinacea: a preliminary, randomized, double-blind, placebo-controlled trial.

Kim LS, Waters RF, Burkholder PM. Research Department, Southwest College , Arizona , USA .

The immunomodulating effects of two Echinacea species, E. purpurea and E. angustifolia and larch arabinogalactan extracted from Larix occidentalis were examined in a randomized, double-blind, placebo-controlled, prospective four-week clinical trial at a naturopathic medical school research center. SUBJECTS/MATERIALS: Forty-eight healthy female volunteers (22-51 y) were randomly assigned to one of six groups: standardized extract of E. purpurea (EP); ultra-refined E. purpurea/E. angustifolia (urEPA); E. purpurea/E. angustifolia (EPA); E. purpurea/E. angustifolia plus larch arabinogalactan (EPALA); larch arabinogalactan (LA); or placebo. METHODS: Immunological tests with enumerative measurements, stool cultures for Lactobacillus acidophilus and yeast, and health-related quality of life (HRQoL) using the Medical Outcomes Study derived SF-36 self-administered questionnaire were assessed at baseline and at four weeks. RESULTS: Complement properdin increased by 21 percent in the EPA group (p<0.05) and by 18 percent in the EPALA group (p<0.05), compared to the placebo group (p>0.05). SF-36 showed improvements in overall physical health, vitality, and emotional health in the same two groups (EPA and EPALA). DISCUSSION: Volunteers in the EPA and EPALA groups had increased production of complement properdin after four weeks of intervention. The increased complement properdin may be an indication of one aspect of immune system stimulation in patients treated with either E. purpurea/E. angustifolia or E. purpurea/E. angustifolia plus larch arabinogalactan.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Phytomedicine. 1999 Nov;6(5):347-9.

Stability of an alkamide and a phenolic phytochemical marker in a hydro-alcoholic extract of Echinacea purpurea root and a dried powder prepared by evaporation of the extract was assessed in storage for 7 months at three temperature regimes: -20, 25 and 40 degrees Celsius. In the extract, the major alkamide, dodeca-2E, 4E, 8Z, 10E/Z-tetraenoic acid isobutyl amide, was not significantly affected by storage at any of the temperatures, but cichoric acid content declined as significantly (P = 0.05) at both 25 degrees C and 40 degrees C as compared to low-temperature storage. In the powder, the major alkamide showed a significantly reduced level at 25 degrees C and 40 degrees C while cichoric acid did not decline significantly. These results suggest that more attention should be given to the effect of formulation and temperature on storage of Echinacea products.

Phytother Res. 2002 Mar;16(2):138-42.

Polysaccharides isolated from Echinacea purpurea herba cell cultures to counteract undesired effects of chemotherapy--a pilot study.

Melchart D, Clemm C, Weber B. Centre for Complementary Medicine Research, Department of Internal Medicine II, Technische Universitat, Munich , Germany .

In an open prospective study with matched historical controls we aimed to evaluate whether a polysaccharide fraction isolated from the herb Echinacea purpurea could counteract the undesired effects of chemotherapy. Fifteen patients with advanced gastric cancer undergoing palliative chemotherapy with etoposide, leucovorin and 5-fluorouracil (ELF) received for 10 days (beginning 3 days before chemotherapy) daily i.v. injections of 2 mg of a polysaccharide fraction isolated from Echinacea purpurea herb cell cultures (EPS-EPO VIIa). The median number of leukocytes 14-16 days after chemotherapy was 3630/microL (range 1470-5770) in the patients receiving EPS-EPO VIIa compared with 2370/microL (870-3950) in the patients of the historical control group (p = 0.015). EPS-EPO VIIa had no clinically relevant effects on phagocytic activity of granulocytes or on lymphocyte subpopulations. Sixty-eight adverse events including two deaths were observed, most likely due to chemotherapy and the general condition of the patients. However, an association with the test intervention cannot be ruled out completely. The results of this pilot study suggest that EPS-EPO VIIa might be effective in reducing chemotherapy-induced leukopenia. The efficacy and safety should be investigated in further studies.

Publication Types:

•  Clinical Trial

•  Controlled Clinical Trial

J Altern Complement Med. 2002 Feb;8(1):49-58.

OBJECTIVE: Tumor amelioration via vaccination/immunization is a practice for which considerable experimental and clinical support is growing. Combination therapies have proven to be more beneficial than treatment with single agents. We hypothesized that immunization of mice with killed erythroleukemia cells prior to the induction of erythroleukemia via injection of viable tumor cells, plus dietary administration of a known immuno-enhancing phytocompound, Echinacea purpurea, would be more effective than immunization alone. DESIGN: A commercially available extract of E. purpurea root, already proven as a natural killer (NK) cell stimulant, was administered via the chow, for periods of 9 days or 3 months after the onset of leukemia to mice which had been injected (immunized) 5 weeks earlier with killed leukemia cells. RESULTS: Immunized mice (+/- E. purpurea) had significantly prolonged life spans versus non-immunized mice, with an even greater proportion of hosts surviving long-term in the E. purpurea-fed group. NK cells, the mediators of nonspecific immunity and well-demonstrated mediators of tumor cytolysis, were very significantly elevated in immunized, leukemic mice receiving E. purpurea in their diet versus those receiving untreated chow. Early in tumor development (9 days), cells mediating specific immunity (T, B lymphocytes) were 10-12 times higher in absolute numbers in the spleens in all immunized, leukemic mice vs unimmunized, leukemic mice at the same stage of tumor progression. CONCLUSIONS: The results demonstrate that combination therapy, involving specific tumor cell immunization, followed by daily phytotherapy (dietary E. purpurea), sensitized the immune cells and led to life span prolongation greater than that provided by immunization alone.

J Chromatogr A. 2002 Feb 1;945(1-2):239-47.

A micellar electrokinetic chromatographic (MEKC) method was developed for the separation of ten phenolic acids including cichoric acid and caftaric acids, specific marker phytochemicals of Echinacea purpurea. The MEKC method involved the use of 70 mM sodium deoxycholate (SDC) in 40 mM borate (pH 9.2) buffer and UV detection at 300 nm. The bile acid was used as biosurfactant able to provided a micellar system with different and more selective properties than sodium dodecyl sulfate. The effects of SDC and borate concentration and buffer pH on the analyte resolution were evaluated. The validated method was applied to the determination of cichoric acid and related compounds in E. purpurea root extracts, and in commercial E. purpurea based dried extracts and tablets.

Ann Allergy Asthma Immunol. 2002 Jan;88(1):42-51.

Adverse reactions associated with echinacea: the Australian experience.

Mullins RJ, Heddle R. John James Medical Centre, Deakin, ACT, Australia .

BACKGROUND: Fifty percent of Australians use complementary and alternative medicines (other than vitamins) in any 12-month period, of which echinacea-containing products are increasingly popular. Recent reports have highlighted the risk of allergic reactions to complementary medicines in atopic patients. OBJECTIVE: To determine the characteristics of adverse reactions linked to use of the popular herbal remedy echinacea. METHODS: Five privately referred patients were evaluated by the authors in their office practice via skin prick testing (SPT) on the volar aspect of the forearm and radioallergosorbent test after adverse reactions to echinacea. As there was little published information on adverse reactions to echinacea, reports to the Australian Adverse Drug Reactions Advisory Committee were reviewed. Those suggestive of possible allergic reactions were evaluated in greater detail by anonymously surveying the healthcare professionals who had reported the cases and from one unreported case. Serum was collected for further analysis where possible. RESULTS: Five cases of adverse reactions to echinacea were personally evaluated by the authors. Two patients suffered anaphylaxis and a third had an acute asthma attack 10 minutes after their first ever dose of echinacea. The fourth patient suffered recurrent episodes of mild asthma each time echinacea was ingested, and the fifth developed a maculopapular rash within 2 days of ingestion which recurred when rechallenged. Three of the patients had positive SPT results. Three reported repeated spontaneous "challenges" and symptoms after further ingestion of echinacea. Fifty-one Australian adverse drug reports implicating echinacea were also reviewed. There were 26 cases suggestive of possible immunoglobulin E-mediated hypersensitivity (4 anaphylaxis, 12 acute asthma, 10 urticaria/angioedema). Of these 26 patients, age ranged from 2 to 58 years, 78% were female and >50% were known to be atopic. Four were hospitalized, 4 reacted after their first known exposure, and 1 patient suffered multiple progressive systemic reactions. Twenty percent of 100 atopic subjects who had never taken echinacea also had positive SPT results to this substance when tested by one of the authors in his office practice. CONCLUSION: Some atopic subjects have positive SPT results to echinacea in the absence of known exposure. Atopic subjects are also overrepresented in those experiencing reactions to echinacea. The possibility that cross-reactivity between echinacea and other environmental allergens may trigger allergic reactions in "echinacea-naive" subjects is supported by the Australian data. Given its widespread (and largely unsupervised) community use, even rare adverse events become inevitable. Atopic patients should be cautioned appropriately.

Publication Types:

•  Case Reports

Int Immunopharmacol. 2002 Feb;2(2-3):381-7.

Echinacea plant extract is widely used for the prevention and the treatment of upper respiratory tract infections. However, the active components in the herb, their optimal dosages and their in vivo effects are still undefined. Using male Sprague-Dawley rats (425- 475 g ), an in vivo study was conducted to examine the immunomodulatory effects of various dose levels of three components, isolated and purified from Echinacea purpurea. The components were cichoric acid, polysaccharides and alkylamides. The rats were gavaged orally two times/day for 4 days with three different concentrations of each of the Echinacea components. Among the components, alkylamides at the dose level of 12 microg/kg body weight/day significantly increased the phagocytic activity as well as phagocytic index of the alveolar macrophages. The alveolar macrophages obtained from this group of rats also produced significantly more TNF-alpha and nitric oxide after an in vitro stimulation with LPS than any other active component or the control. None of the components at any concentration had any effect on the release of TNF-alpha, IFN-gamma and IL-2 by the splenocytes. These results suggest that the alkylamides are one of the active constituents of E. purpurea plant. At a dose level of approximately 12 microg/kg body weight/day they effectively stimulate alveolar macrophage function in healthy rats. The immunomodulatory effects of alkylamides appear to be more pronounced in lungs than in spleen.

J Ethnopharmacol. 2002 Feb;79(2):265-72.

Anti-inflammatory and cicatrizing activity of Echinacea pallida Nutt. root extract.

Speroni E, Govoni P, Guizzardi S. Department of Pharmacology, University of Bologna , Italy .

Among the different species belonging to the Echinacea family, largely used in traditional medicine, Echinacea pallida, Echinacea purpurea and Echinacea angustifolia were investigated. These different species, due to their difficult identification, were commonly confused in the past and probably used indifferently for the same therapeutic purposes. In fact, the three species have in common, some pharmacological activities, based on the presence of active compounds that act additively and synergistically. Nevertheless, the composition of each species has slight variation in the amount of each active component. In particular, echinacoside, a caffeoyl derivative, is present in E. pallida and only in traces in E. angustifolia. It seems to have protective effects on skin connective tissue and to enhance wound healing. The anti-inflammatory and wound healing activities of echinacoside, compared with the ones of the total root extract of E. pallida and E. angustifolia, were examined in rats, after topical application. The tissues of the treated animals were evaluated after 24, 48 and 72 h treatment and excised for histological observation at the end of the experiment. Results confirm the good anti-inflammatory and wound healing properties of E. pallida and of its constituent echinacoside, with respect to E. purpurea and control. This activity probably resides in the antihyaluronidase activity of echinacoside.

Planta Med. 2001 Dec;67(9):863-4.

Absorption of dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamides after oral application of Echinacea purpurea tincture.

Dietz B, Heilmann J, Bauer R.

Alkamides are suspected to contribute to the activity of Echinacea preparations. In preliminary experiments a quantification method for dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamides in human blood has been developed by which it was possible to detect dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamides in human blood after oral application of Echinacea purpurea mother tincture.

Publication Types:

•  Letter

Immunopharmacol Immunotoxicol. 2001 Aug;23(3):411-21.

Multiple immune functions in rats fed Echinacea extracts.

South EH, Exon JH. Department of Food Science and Toxicology, University of Idaho , USA .

This study evaluated acquired-immune functions representing the three major branches of the immune system in male rats fed a commercially available echinacea product. An additional comparison of effects on antibody formation in male and female rats was done using the commercial echinacea product and two echinacea tinctures marketed by local herbalists. In initial testing, we found no evidence of altered natural killer cell activity, T cell-mediated delayed-type hypersensitivity, or specific antibody formation in male rats given either a 225 mg/kg or 50 mg/kg of the commercial echinacea for 6 weeks. Antibody formation was significantly suppressed in female but not male rats given 250 mg/kg for 2 weeks of the commercial echinacea. The local products tested had no effect on antibody formation. We concluded that our study provided no supporting evidence for immunostimulatory activity by the echinacea preparations we examined and, in fact, may be immunosuppressive under some conditions.

Carbohydr Res. 2001 Nov 8;336(2):107-15.

For the characterization of the supposed epitope of an arabinogalactan, isolated from the extract of the cell-cultured Echinacea purpurea, the title hexasaccharide was synthesized. The whole synthetic route was based on the 6-O-(methoxydimethyl)methyl ether (MIP) protecting group strategy. 2-O-Benzyl-3,4-O-isopropylidene-6-O-(methoxydimethyl)methyl-beta-D-galactopyranosyl-(1-->6)-1,2:3,4-di-O-isopropylidene-alpha-D-galactopyranose was used to prepare the desired glycosyl donor and glycosyl acceptor both carrying a persistent O-benzyl group at position 2'. Reaction of the digalactose donor and the digalactose acceptor resulted in a beta-(1-->6)-linked galactose-containing tetrasaccharide in which OH-2' and OH-2"' were substituted with benzyl groups. Hydrogenolytic removal of the benzyl groups of the tetragalactose compound gave the diol aglycon which was diarabinosylated in one step to furnish the protected target compound, whose deprotection led to the title hexasaccharide. All of the synthesized compounds were characterized by 1H and 13C NMR spectra, as well as by MALDI-TOF mass-spectrometry measurements.

Can Fam Physician. 2001 Sep;47:1727-8.

Can herbal products be used safely during pregnancy? Focus on echinacea.

Gallo M, Koren G.

QUESTION: Many of my patients are now using herbal medicines; some even use them during pregnancy. As we enter the "cold and flu" season, many are inquiring about use of the herb echinacea to prevent these ailments. Is there any evidence to suggest that use of echinacea during pregnancy is safe? ANSWER: Although herbal products have been used in the past during pregnancy and delivery, there is little evidence showing they are safe. Many authoritative reviews of echinacea report that its safety for use during pregnancy has not been established. A recent Motherisk study showed that use of echinacea during the first trimester of pregnancy was not associated with increased risk of major malformations.

Arzneimittelforschung. 2001;51(7):563-8.

Efficacy of Echinacea purpurea in patients with a common cold. A placebo-controlled, randomised, double-blind clinical trial.

Schulten B, Bulitta M, Ballering-Bruhl B. Company Medical Service, Madaus AG, Cologne , Germany .

Common colds are one of the most frequent acute illnesses with major economical impact. Echinaceae purpureae herba (Echinacin, EC31J0) has shown promising results in the relief of common cold symptoms and the time taken to improvement compared to placebo. This study was aimed to confirm these findings by performing a randomised, double-blind, placebo-controlled clinical trial. A total of 80 adult male or female patients with first signs of a cold were recruited. The number of days of illness with a complete picture of the common cold (defined by the modified Jackson score of at least 5 points and experience of rhinorrhea and/or a subjective sensation of having a cold) was the primary end-point. In the verum group the median time of illness was 6.0 days compared to 9.0 days in the placebo group, assigning zero time for patients without a complete picture (one-sided p = 0.0112). EC31J0 was well tolerated and clinically effective in alleviating symptoms more rapidly than placebo in patients with a common cold.

Publication Types:

•  Clinical Trial

•  Clinical Trial, Phase IV

•  Randomized Controlled Trial

Pharmazie. 2001 Jul;56(7):552-3.

J Altern Complement Med. 2001 Jun;7(3):241-51.

OBJECTIVE: We recently showed that daily dietary administration of Echinacea purpurea root extract to normal mice for as little as 1 week resulted in significant elevations of natural-killer (NK) cells (immune cells that are cytolytic to virus-containing cells and many tumor cells). Such boosting of this fundamental immune cell population suggests a prophylactic role for this herb in normal animals. Based on this evidence, our goal in the present work was to assess the role of dietary administration of this herbal extract to mice bearing leukemia, a type of tumor well known to be a target for NK cells. DESIGN: A commercially available root extract of E. purpurea, which we have already shown to be highly effective in mice, was administered daily for 50 days from the onset of leukemia (day 0). Control leukemic mice received no extract. Other leukemic mice received the NK-enhancing neurohormone, melatonin, administered precisely as above. In all treatment and control categories, some mice were sampled at 9 days after tumor onset, others were sampled at 3 months, and still others were left to assess treatment effect on life span. RESULTS: At 9 days (intermediate stage leukemia; death beginning by day 17-18), E. purpurea-treated mice had a 2.5-fold increase in the absolute numbers of NK cells in their spleens. By 3 months after leukemia onset, E. purpurea-treated mice still had 2-3 times the normal numbers of NK cells in their spleens. No leukemic, untreated (control) mice remained alive at 3 months, hence the comparison with normal animals. Moreover, at 3 months post-tumor onset, all the major hemopoietic and immune cell lineages in their bone marrow birth site, were recorded at normal numbers, in E. purpurea-consuming, leukemic mice. The survival advantage provided by administering these leukemic mice with E. purpurea was highly significant versus untreated, leukemic mice when analyzed by Kaplan-Meier survival statistics. CONCLUSION: The present study has provided the first systematic analysis, under controlled laboratory conditions, of the effect(s) of the botanical, E. purpurea, in vivo, in leukemic hosts. The profoundly positive effects of this herb in disease abatement observed in this study suggest the therapeutic potential of E. purpurea, at least with respect to leukemia, if not other tumors as well.

J Pharm Pharmacol. 2001 Jun;53(6):849-57.

Comparison of chemical components and antioxidants capacity of different Echinacea species.

Sloley BD, Urichuk LJ, Tywin C. CV Technologies, Edmonton , Alberta , Canada .

Alcoholic extracts of the roots and leaves of three Echinacea species (E. purpurea, E. angustifolia and E. pallida) were analysed for the presence of characteristic chemicals by HPLC directly coupled to ultraviolet absorbance and electrospray mass spectrometric detectors. The method permitted rapid characterization and tentative identification of a large number of caffeoyl conjugates and alkamides in all the samples investigated. The roots of the three species differed markedly in their contents of characteristic compounds. Cichoric acid and verbascoside predominated in extracts of E. purpurea root whereas cynarine and dodeca-2E,4E,8Z,10Z/E-tetraenoic acid isobutylamide were the major chemicals characteristic of E. angustifolia root extracts. Echinacoside and 6-O-caffeoylechinacoside predominated in extracts of E. pallida roots. Characteristic alkamides were also examined by electrospray tandem mass spectrometry (MS/MS) and these compounds provided characteristic fragmentation patterns. Extracts of the roots and leaves of all three species were found to have antioxidant properties in a free radical scavenging assay and in a lipid peroxidation assay.

Clin Pediatr (Phila). 2001 May;40(5):265-9.

The use of dietary supplements in pediatrics: a study of echinacea.

Mark JD, Grant KL, Barton LL. Department of Pediatrics, College of Pharmacy , University of Arizona , Tucson , USA .

Alternative medical therapies are commonly used and have increased in popularity. Although patients may not always disclose the use of alternative therapies, they may seek advice regarding their use, especially for children. Regulation and standardization of these modalities, especially botanicals, is incomplete. The University of Arizona has initiated a study of the use of echinacea in the prevention of recurrent otitis media. A review of echinacea preparations was undertaken, and this report discusses the complexities surrounding the use of this dietary supplement. The number and diversity of echinacea preparations are detailed; the role of the physician as "botanical" advisor to patients and families is examined.

Publication Types:

•  Review

•  Review, Tutorial

J Agric Food Chem. 2001 Apr;49(4):1702-6.

A proposed standard extraction and HPLC analysis method has been used to measure typical levels of various phenolic compounds in the medicinally used Echinacea species. Chicoric acid was the main phenolic in E. purpurea roots (mean 2.27% summer, 1.68% autumn) and tops (2.02% summer, 0.52% autumn), and echinacoside was the main phenolic in E. angustifolia (1.04%) and E. pallida roots (0.34%). Caftaric acid was the other main phenolic compound in E. purpurea roots (0.40% summer, 0.35% autumn) and tops (0.82% summer, 0.18% autumn), and cynarin was a characteristic component of E. angustifolia roots (0.12%). Enzymatic browning during extraction could reduce the measured levels of phenolic compounds by >50%. Colorimetric analyses for total phenolics correlated well with the HPLC results for E. purpurea and E. angustifolia, but the colorimetric method gave higher values.

Phytochemistry. 2001 Mar;56(6):543-9.

Predicting quantitative phytochemical markers in single Echinacea plants or clones from their DNA fingerprints.

Baum BR, Mechanda S, Livesey JF. Agriculture & Agri-Food Canada , Research Branch, Eastern Cereal and Oilseed Research Centre, Ottawa , ON .

Amplified restricted fragment length polymorphism (AFLP) data analysis was found to be a statistically significant predictor of phytochemical markers in cultivated Echinacea purpurea germplasm and some related wild species. Over 50 accessions grown under greenhouse conditions were subjected to AFLP analysis and the same assessed for content of tetraene and cichoric acid by high pressure liquid chromatography. The first and second canonical correlation of DNA variables and the phytochemical variables were significant. Individual regressions of cichoric acid and dodeca-2E, 4E, 8Z, 10E/Z-tetraenoic acid isobutyl amide predicted by DNA polymorphism analysis against actual HPLC determined values were nearly linear. Mantel's test showed that there was a weak correlation but a strong association of values of the phytochemical variables and the DNA polymorphism data.

Nihon Rinsho Meneki Gakkai Kaishi. 2001 Feb;24(1):10-20.

Forsch Komplementarmed Klass Naturheilkd. 2000 Dec;7(6):294-300.

Cichoric acid and Dodeca 2E, 4E, 8Z, 10E/Z-tetraenoic acid isobutylamide (alkamides 8, 9) are described as immunomodulating active components of Echinacea. We quantified both substances in 25 Echinacea-containing remedies customary in trade. Concerning both active components, we found highly concentrated remedies as well as remedies without any detectable cichoric acid or alkamides. The concentration of both active components varied extremely depending on the type of remedy (homeopathic mother tincture, pressed juice, tablets, spagyric tincture), on the Echinacea-species (Echinacea angustifolia, Echinacea pallida, Echinacea purpurea) and on the part of the plant (root, herb, whole plant). Moreover, we found large differences between comparable drugs of different manufacturers and between different charges of the same remedy. We recommend that preclinical and clinical studies with Echinacea-containing drugs should always include the quantification of the potentially active components. We are convinced, that in the long term this will help to clarify how the different active components contribute to the immunomodulating effect of Echinacea.

J Nat Prod. 2000 Dec;63(12):1615-8.

Cichoric acid (2R,3R-O-dicaffeoyltartaric acid) (1) is highly susceptible to enzymatic degradation during the preparation of Echinacea purpurea products. Degradation of 1 and other caffeic acid derivatives can be inhibited by antioxidants added to the extraction solvent or in buffered protein extracts saturated with nitrogen. Inhibitor studies conducted with protein extracts prepared from dried overground parts of E. purpurea revealed that polyphenol oxidases (PPO) but not peroxidases are responsible for the oxidative degradation of exogenous and endogenous caffeic acid derivatives. With a view to stabilizing aqueous extracts with respect to their content of 1, the effects of ascorbic acid and ethanol were tested. Compound 1 was not stable under conditions where oxidative processes could almost be excluded. It was found that an esterase hydrolyzing the ester bonds between tartaric acid and caffeic acid is still active under PPO inhibitory conditions. Finally, addition of 40% ethanol and 50 mM ascorbic acid to aqueous extracts of "Echinaceae purpureae herba" resulted in a constant amount of cichoric acid over four weeks.

Arch Intern Med. 2000 Nov 13;160(20):3141-3.

Pregnancy outcome following gestational exposure to echinacea: a prospective controlled study.

Gallo M, Sarkar M, Au W. The Motherisk Program, Division of Clinical Pharmacology/Toxicology, The Hospital for Sick Children, Toronto , Ontario , Canada .

BACKGROUND: Echinacea products are among the most popular phytomedicines on the North American market. Since at least half of all pregnancies are unplanned, many women inadvertently use echinacea in their first trimester. Presently, there is a paucity of information regarding the gestational safety of this herb. The primary objective of this study was to evaluate the safety of echinacea in pregnancy when used for upper respiratory tract ailments. PATIENTS AND METHODS: The study group consisted of women who were prospectively followed up after contacting the Motherisk Program regarding the gestational use of echinacea. This cohort was disease-matched to women exposed to nonteratogenic agents by maternal age, alcohol, and cigarette use. Rates of major and minor malformations between the groups were compared. RESULTS: A total of 206 women were enrolled in the study group after using echinacea products during pregnancy; 112 women used the herb in the first trimester. There were a total of 195 live births, including 3 sets of twins, 13 spontaneous abortions, and 1 therapeutic abortion. Six major malformations were reported, including 1 chromosomal abnormality, and 4 of these malformations occurred with echinacea exposure in the first trimester. In the control group, there were 206 women with 198 live births, 7 spontaneous abortions, and 1 therapeutic abortion. Seven major malformations were reported. There were no statistical differences between the study and control groups for any of the end points analyzed. CONCLUSIONS: This first prospective study suggests that gestational use of echinacea during organogenesis is not associated with an increased risk for major malformations.

J Leukoc Biol. 2000 Oct;68(4):503-10.

J Agric Food Chem. 2000 Sep;48(9):4187-92.

Different drying methods, such as freeze-drying (FD), vacuum microwave drying (VMD), and air-drying (AD), were applied to fresh roots and leaves of Canadian-grown Echinacea purpurea to determine the optimal method for preserving alkamide levels. Using HPLC, six alkamide fractions (alkamides 1, 2, 3, 6a/6, 7, 8/9) were quantitated in dried roots, whereas four alkamide fractions (alkamides 1, 2, 3, 8/9) were measured in dried leaves. Different elution conditions used in HPLC for alkamide analysis did not affect the eluted fractions nor the quantitation of different alkamides. Individual alkamide concentrations in roots and leaves were affected by the drying methods used. To preserve higher levels of total alkamides, FD was found to be the best method, VMD was a superior method for drying roots than AD at 70 degrees C, while AD at 50 degrees C was the preferred method for drying leaves of E. purpurea.

J Agric Food Chem. 2000 Sep;48(9):4182-6.

Different drying methods were applied to fresh Canadian-grown Echinacea purpurea flowers to determine optimal drying procedures for preserving caffeic acid derivatives. Fresh flowers of E. purpurea were dried by freeze-drying (FD), vacuum microwave drying with full vacuum (VMD), and air-drying (AD) at 25, 40, and 70 degrees C. Using HPLC, chicoric acid and caftaric acid levels were quantitated in dried flowers. These acids were significantly affected by the drying method conditions used. Although significant (p < 0.05) loss of chicoric acid was observed when flowers were stored at high moisture, VMD flowers with a low moisture content retained the highest levels of chicoric acid and caftaric acid similar to FD flowers. Flowers that were AD at 25 degrees C retained about 50%, while those dried by AD at 70 degrees C resulted in the lowest retention of these acids. Although flowers dried by AD at 40 degrees C retained relatively high amounts of chicoric acid and caftaric acid, the time (55 h) required to reach optimal drying was considerably longer than that (47 min) for VMD.

Carbohydr Res. 2000 Aug 7;327(4):497-504.

An arabinogalactan-protein (AGP) from pressed juice of Echinacea purpurea herb was isolated from a high molecular weight fraction by precipitation with the beta-glucosyl Yariv reagent, followed by gel-permeation chromatography. It revealed characteristic features of other AGPs: i.e., a high amount of polysaccharide (83%) with a ratio of galactose to arabinose of 1.8:1, some uronic acids (4-5%), and a low protein content (7%) with high levels of serine, alanine and hydroxyproline. The molecular weight was estimated to be 1.2 x 10(6) Da. Linkage and 13C NMR analyses showed that the AGP is composed of a highly branched core polysaccharide of 3-, 6-, and 3,6-linked Galp residues with terminal Araf, GlcAp and terminal units of Araf-(1-->5)-Araf-(1-->. Partial acid hydrolysis resulted in loss of Araf residues at the periphery of the molecule. Complete loss of reactivity toward the beta-glucosyl Yariv antigen was then noticed.

Exp Gerontol. 2000 Aug;35(5):627-39.

A growing body of anecdotal evidence in young and adult humans suggests that certain phytochemicals have the capacity to ameliorate tumors and reduce infections, especially those mediated by virus, in vivo. These indications prompted us, therefore, to investigate the potentially immuno-stimulating effect of one such phytocompound, Echinacea purpurea, on natural killer (NK) cells since these cells are active in spontaneous, non-specific immunity against neoplasms and virus-mediated infections. We elected to study aging mice, since, at this stage of life, like humans, the above-mentioned afflictions increase in frequency. We had previously found that neither the cytokine, interleukin-2, nor the pharmacological agent, indomethacin, both potent stimulators of NK cell numbers/function in younger adult mice, was effective in stimulating NK cells in elderly mice. The present study was designed to assess the numbers/production of NK cells in the spleen and bone marrow of aging, normal mice, after in vivo dietary administration of E. purpurea (14 days), or, after injection of thyroxin, a stimulant of NK cell function (10 days). Immunoperoxidase labeling techniques, coupled with hematologic tetrachrome staining were used to identify NK cells in both the spleen (primary site of NK cell function) and the bone marrow (site of NK cell generation). Double immunofluorscence staining, employing propidium iodide, was used to assess NK cell lytic function. Our results revealed that E. purpurea, but not thyroxin, had the capacity to increase NK cell numbers, in aging mice, reflecting increased new NK cell production in their bone marrow generation site, leading to an increase in the absolute numbers of NK cells in the spleen, their primary destiny. The E. purpurea-mediated increase in NK cell numbers was indeed paralleled by an increase in their anti-tumor, lytic functional capacity. Collectively, the data indicate that E. purpurea, at least, and possibly other plant compounds, appear to contain phytochemicals capable of stimulating de novo production of NK cells, as well as augmenting their cytolytic function, in animals of advanced age.

J Altern Complement Med. 2000 Aug;6(4):327-34.

The efficacy of echinacea compound herbal tea preparation on the severity and duration of upper respiratory and flu symptoms: a randomized, double-blind placebo-controlled study.

Lindenmuth GF, Lindenmuth EB. Rest Haven-York, York College of Pennsylvania , USA .

OBJECTIVES: The aim of this study was to determine the efficacy of an echinacea compound herbal tea preparation (Echinacea Plus) given at early onset of cold or flu symptoms in a random assignment double-blind placebo-controlled study. DESIGN AND SUBJECTS: A total of 95 subjects with early symptoms of cold or flu (runny nose, scratchy throat, fever) were randomly assigned to receive Echinacea Plus tea five to six cups per day titrating to 1 over 5 days or placebo in a double-blind situation. Each participant completed a questionnaire 14 days after beginning the program. The efficacy, number of days the symptoms lasted, and number of days for change were measured with a self scoring questionnaire. RESULTS: The study period was 90 days (January 1, 1999 to March 30, 1999). There was a significant difference between the experimental group (Echinacea Plus) and control group (placebo) for all 3 questions measured: p < 0.001. There were no negative effects reported by any of the subjects in either group. CONCLUSIONS: Treatment with Echinacea Plus tea at early onset of cold or flu symptoms was effective for relieving these symptoms in a shorter period of time than a placebo.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Pharmacotherapy. 2000 Jun;20(6):690-7.

Evaluation of echinacea for treatment of the common cold.

Giles JT, Palat CT 3 rd . School of Pharmacy, Virginia Commonwealth University, Medical College of Virginia Campus, Richmond, USA.

Considered to have immunostimulating activity, echinacea is a widely used phytomedicinal for treatment of the common cold and upper respiratory tract infections (URTIs). We reviewed the literature from the MEDLINE database (January 1966-July 1999), International Pharmaceutical Abstracts (IPA) online database, Cambridge Scientific Abstracts Biological Sciences online database, Alt-Health Watch online database, EMBase CD-ROM database, and references from published articles, reviews, and letters to evaluate evidence from clinical trials of echinacea's purported efficacy for treating or preventing URTIs. Twelve clinical studies published from 1961-1997 concluded that echinacea was efficacious for treating the common cold, but the results are unclear due to inherent flaws in study design. Five trials were published since 1997; two showed that echinacea lacked efficacy for treating and preventing URTI symptoms, and three concluded that it was effective in reducing the frequency, duration, and severity of common cold symptoms. Again, these results are unclear because of methodologic uncertainties, such as small populations and use of noncommercially available, nonstandardized dosage forms. Although evidence for echinacea's efficacy is inconclusive, it appears to be safe. Patients without contraindications to it may not be dissuaded from using an appropriate preparation to treat the common cold.

Publication Types:

•  Review

•  Review, Tutorial

Biochem Pharmacol. 2000 Jul 15;60(2):155-8.

Use of echinacea in medicine.

Percival SS. Food Science and Human Nutrition Department, The University of Florida , Gainesville , FL USA .

Echinacea, also known as the purple coneflower, is an herbal medicine that has been used for centuries, customarily as a treatment for the common cold, coughs, bronchitis, upper respiratory infections, and some inflammatory conditions. Research on echinacea, including clinical trials, is limited and largely in German. More information is needed before a definitive statement about the efficacy of echinacea can be made. Future work needs to clearly identify the species of echinacea and distinguish between the efficacy of the different plant parts (roots versus upper plant parts). Although many of the active compounds of echinacea have been identified, the mechanism of action is not known, nor is the bioavailability, relative potency, or synergistic effects of the active compounds known. Interpretation of existing literature suggests that echinacea should be used as a treatment for illness, not as a means for prevention of illness. The consensus of the studies reviewed in this article is that echinacea is indeed effective in reducing the duration and severity of symptoms, but that this effect is noted only with certain preparations of echinacea. Studies show that the plant and its active components affect the phagocytic immune system, but not the specifically acquired immune system.

Publication Types:

•  Review

•  Review, Tutorial

Planta Med. 2000 Apr;66(3):241-4.

This study demonstrated that plant extracts containing acetylenic isobutylamides and polyacetylenes, previously reported as occurring in Echinacea, have phototoxic antimicrobial activity against fungi, including clinically relevant pathogenic fungi. Results show that hexane extracts of Echinacea variably inhibit growth of yeast strains of Saccharomyces cerevisiae, Candida shehata, C. kefyr, C. albicans, C. steatulytica and C. tropicalis under near UV irradiation (phototoxicity) and to a lower extent without irradiation (conventional antifungal activity). The presence of polyacetylenes and alkylamides in extracts of different organs was confirmed in Echinacea purpurea by HPLC in agreement with previously reported data in the literature, and was related to phototoxic activity. Two representative pure compounds, undeca-2E,4Z-diene-8,10-diynoic acid isobutylamide and dodeca-2E,4E,8Z,10E/Z-tetraenoic acid isobutylamide, were isolated from Echinacea purpurea root extracts, and compared in a disk assay (5 micrograms/disk) with the highly conjugated trideca-1-ene-3,5,7,9,10-pentayne (previously isolated in our laboratory and found here in E. purpurea). Significant phototoxicity was demonstrated by pure trideca-1-ene-3,5,7,9,10-pentayne, while only minor phototoxicity was induced by the other two acetylenic compounds. Phototoxic activity of Echinacea spp. is primarily attributed to the ketoalkenes and ketoalkynes abundantly present in the roots.

J Agric Food Chem. 2000 May;48(5):1466-72.

Methanol extracts of freeze-dried Echinacea (E. angustifolia, E. pallida, and E. purpurea) roots were examined for free radical scavenging capacities and antioxidant activities. Root extracts of E. angustifolia, E. pallida, and E. purpurea were capable of scavenging hydroxyl radical. Similar scavenging activities for each variety were found for both 1,1-diphenyl-2-picrylhydrazyl radical and ABTS radical. Meanwhile, antioxidant activities of all three varieties of Echinacea were found to delay the formation of conjugated diene hydroperoxide induced by the thermal decomposition of 2, 2'-azobis(2-amidinopropane) dihydrochloride and extend the lag phase of peroxidation of soybean liposomes. Echinacea root extracts suppressed the oxidation of human low-density lipoprotein, as evaluated by reduced agarose electrophoretic mobility following oxidative modification by Cu(2+). The mechanisms of antioxidant activity of extracts derived from Echinacea roots included free radical scavenging and transition metal chelating.

Cochrane Database Syst Rev. 2000;(2):CD000530.

Echinacea for preventing and treating the common cold.

Melchart D, Linde K, Fischer P. Munchener Modell - Centre for Complementary Medicine Research, Technical University/Ludwig-Maximilians-University, Munich , Germany ,

BACKGROUND: Extracts of the plant Echinacea (family Compositae) are widely used in some European countries and the USA for upper respiratory tract infections. OBJECTIVES: The objective of this review was to assess the effects of preparations containing extracts of Echinacea in the prevention and treatment of the common cold. SEARCH STRATEGY: We searched the Cochrane Acute Respiratory Infections Group and Complementary Medicine Field's trials registers, MEDLINE, EMBASE, Phytodok and reference lists of articles. We also contacted researchers and manufacturers. Date of last search: Spring 1998. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing preparations containing an extract of Echinacea compared with a placebo, no treatment, or another treatment for common colds. DATA COLLECTION AND ANALYSIS: At least two independent reviewers assessed trial quality and extracted data. MAIN RESULTS: Sixteen trials (eight prevention trials, and eight trials on treatment of upper respiratory tract infections) with a total of 3396 participants were included. Variation in preparations investigated and methodological quality of trials precluded quantitative meta-analysis. Overall, the results suggested that some Echinacea preparations may be better than placebo. REVIEWER'S CONCLUSIONS: The majority of the available studies report positive results. However there is not enough evidence to recommend a specific Echinacea product, or Echinacea preparations for the treatment or prevention of common colds.

Publication Types:

•  Review

•  Review, Academic

Planta Med. 2000 Feb;66(1):54-6.

Alkamide levels in Echinacea purpurea: effects of processing, drying and storage.

Perry NB, van Klink JW, Burgess EJ. Plant Extracts Research Unit, New Zealand Institute for Crop & Food Research Ltd, University of Otago , Dunedin , New Zealand .

The effects of processing, drying, and storage time and temperature on alkamide levels in Echinacea purpurea roots are described. Chopping altered the levels of some alkamides slightly, whereas drying had no effect. Levels of all alkamides fell by over 80% during storage at 24 degrees C for 64 weeks. Alkamide levels also dropped significantly during storage at -18 degrees C.

J Agric Food Chem. 1999 Aug;47(8):3081-5.

Volatile components of roots, stems, leaves, and flowers of Echinacea species.

Mazza G. Food Research Program, Agriculture and Agri-Food Canada, Pacific Agri-Food Research Centre, Summerland, British Columbia, Canada

The headspace volatile components of roots, stems, leaves, and flowers of Echinacea angustifolia,E. pallida, and E. purpurea were analyzed by capillary gas chromatography/mass spectrometry (GC/MS). Over 70 compounds were identified in the samples. All plant tissues, irrespective of the species, contain acetaldehyde, dimethyl sulfide, camphene, hexanal, beta-pinene, and limonene. The main headspace constituents of the aerial parts of the plant are beta-myrcene, alpha-pinene, limonene, camphene, beta-pinene, trans-ocimene, 3-hexen-1-ol, and 2-methyl-4-pentenal. The major headspace components of root tissue are alpha-phellandrene (present only in the roots of E. purpurea and E.angustifolia), dimethyl sulfide, 2-methylbutanal, 3-methylbutanal, 2-methylpropanal, acetaldehyde, camphene, 2-propanal, and limonene. Aldehydes, particularly butanals and propanals, make up 41-57% of the headspace of root tissue, 19-29% of the headspace of the leaf tissue, and only 6-14% of the headspace of flower and stem tissues. Terpenoids including alpha- and beta-pinene, beta-myrcene, ocimene, limonene, camphene, and terpinene make up 81-91% of the headspace of flowers and stems, 46-58% of the headspace of the leaf tissue, and only 6-21% of the roots. Of the 70 compounds identified, >50 are reported in Echinacea for the first time.

Adv Ther. 1999 Jan-Feb;16(1):51-70.

Efficacy and mode of action of an immunomodulator herbal preparation containing Echinacea, wild indigo, and white cedar.

Wustenberg P, Henneicke-von Zepelin HH, Kohler G.

Using the example of an allopathic herbal combined preparation containing Echinacea root, wild indigo root, and white cedar leaf tips (Echinaceae radix + Baptisiae tinctoriae radix + Thujae occidentalis herba = Esberitox N), the efficacy and mode of action of a phytoimmunomodulator, or immune system enhancer, is described. Efficacy of the immunomodulator has been demonstrated in studies of acute viral respiratory tract infections and infections requiring antibiotic therapy. In a recent study compliant to GCP, the therapeutic superiority of the herbal immunomodulator over placebo was confirmed as statistically significant and clinically relevant. The present overview describes a model of the antigen-independent mode of action of phytoimmunomodulation ("immunobalancing").

Publication Types:

•  Review

•  Review, Tutorial

J Fam Pract. 1999 Aug;48(8):628-35.

Echinacea for upper respiratory infection.

Barrett B, Vohmann M, Calabrese C. Department of Family Medicine, University of Wisconsin-Madison , USA .

OBJECTIVES: To review the evidence regarding the effectiveness of orally ingested Echinacea extracts in reducing the incidence, severity, or duration of acute upper respiratory infections (URIs). SEARCH STRATEGIES: Information from a wide range of sources was used as background material. More than 100 articles, books, and book chapters were reviewed for content and further references. Database searches, bibliographic reviews, and conversations with experts were carried out iteratively from January 1997 to February 1999. SELECTION CRITERIA: Published or unpublished reports of all blinded placebo-controlled randomized trials of any Echinacea formulation used as a treatment or for the prevention of URIs. DATA COLLECTION AND ANALYSIS: Review considerations included randomization, blinding, power, validity and clinical relevance of outcome measurements, inclusion and exclusion criteria, indistinguishability of treatment and placebo, and appropriateness of conclusions for the data presented. MAIN RESULTS. Nine treatment trials and 4 prevention trials fitting the selection criteria were found. Eight of the treatment trials reported generally positive results, and 3 of the prevention trials reported marginal benefit. Methodologic quality of the majority of the trials was modest. CONCLUSIONS: Evidence from published trials suggests that Echinacea may be beneficial for the early treatment of acute URIs. The influence of publication bias on those results is unknown. Echinacea preparations vary widely in composition, and are often found in combination with other potentially active constituents, making specific dose recommendations problematic. There is very little evidence supporting the prolonged use of Echinacea for the prevention of URIs.

Publication Types:

•  Review

•  Review Literature

Wien Med Wochenschr. 1999;149(8-10):185-9.

[Extract of the Echinacea purpurea herb: an allopathic phytoimmunostimulant]

Bauer R, Hoheisel O, Stuhlfauth I. Institut fur Pharmazeutische Biologie der Heinrich-Heine-Universitat, Dusseldorf, Deutschland.

In Northamerican folk medicine Echinacea purpurea L. Moench (purple coneflower) was used as a medicinal plant. Nowadays various formulations containing stabilized or dried pressed juice from Echinacea purpurea as an active ingredient are often administered to treat common colds. These preparations are very well tolerated and safe. Allergic reactions, mainly reversible skin reactions, may occur especially in persons showing hypersensibility after contact with plants from the Compositae family. Pharmacological data let assume purple coneflower pressed juice preparations stimulate the innate immune system and increase the resistance to common colds. In this context the stimulation of the oxidative burst as well as the modulation on monokine secretion by the pressed juice of purple coneflower are reviewed. Also relevant clinical studies are presented concerning the treatment of infections respectively of common cold.

Publication Types:

•  Review

•  Review, Tutorial

Immunol Lett. 1999 Jun 1;68(2-3):391-5.

A number of immunomodulatory effects have been attributed to the medicinal plants Echinacea angustifolia and Goldenseal (Hydrastis canadensis); however, little is known about whether treatment with these plants can enhance antigen-specific immunity. We investigated the antigen-specific in vivo immunomodulatory potential of continuous treatment with Echinacea and Goldenseal root extract over a period of 6 weeks using rats that were injected with the novel antigen keyhole limpet hemocyanin (KLH) and re-exposed to KLH after the initial exposure. Immunoglobulin production was monitored via ELISA continuously over a period of 6 weeks. The Echinacea-treated group showed a significant augmentation of their primary and secondary IgG response to the antigen, whereas the Goldenseal-treated group showed an increase in the primary IgM response during the first 2 weeks of treatment. Our results suggest that medicinal plants like Echinacea or Goldenseal may enhance immune function by increasing antigen-specific immunoglobulin production.

Phytomedicine. 1999 Mar;6(1):1-6.

Echinaforce and other Echinacea fresh plant preparations in the treatment of the common cold. A randomized, placebo controlled, double-blind clinical trial.

Brinkeborn RM. Elisabeth Hospital , Wallingatan, Uppsala , Sweden .

The aim of this randomized, double-blind, placebo controlled study was to investigate the efficacy and safety of different doses and preparations of Echinacea purpurea in the treatment of common cold. 246 of 559 recruited healthy, adult volunteers caught a common cold and took 3 times daily 2 tablets of either Echinaforce (Echinacea purpurea-preparation from 95% herba and 5% radix), Echinacea purpurea concentrate (same preparation at 7 times higher concentration), special Echinacea purpurea radix preparation (totally different from that of Echinaforce) or placebo until they felt healthy again but not longer than 7 days. The primary endpoint was the relative reduction of the complaint index defined by 12 symptoms during common cold according to the doctor's record. Echinaforce and its concentrated preparation were significantly more effective than the special Echinacea extract or placebo. All treatments were well tolerated. Among the Echinacea groups the frequency of adverse events was not significantly higher than in the placebo group. Therefore, Echinacea concentrate as well as Echinaforce represent a low-risk and effective alternative to the standard symptomatic medicines in the acute treatment of common cold.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Arch Fam Med. 1998 Nov-Dec;7(6):541-5.

Echinacea root extracts for the prevention of upper respiratory tract infections: a double-blind, placebo-controlled randomized trial.

Melchart D, Walther E, Linde K. Center for Complementary Medicine Research, Technische Universitat, Munich , Germany . Muenchener.

OBJECTIVE: To investigate the safety and efficacy of 2 extracts of echinacea for preventing upper respiratory tract infections. DESIGN: Three-armed, randomized, double-blind, placebo-controlled trial. SETTING: Four military institutions and 1 industrial plant. PARTICIPANTS: Three hundred two volunteers without acute illness at time of enrollment. INTERVENTIONS: Ethanolic extract from Echinacea purpurea roots, Echinacea angustifolia roots, or placebo, given orally for 12 weeks. MAIN OUTCOME MEASURE: Time until the first upper respiratory tract infection (time to event). Secondary outcome measures were the number of participants with at least 1 infection, global assessment, and adverse effects. RESULTS: The time until occurrence of the first upper respiratory tract infection was 66 days (95% confidence interval [CI], 61-72 days) in the E angustifolia group, 69 days (95% CI, 64-74 days) in the E purpurea group, and 65 days (95% CI, 59-70 days) in the placebo group (P = .49). In the placebo group, 36.7% had an infection. In the treatment groups, 32.0% in the E angustifolia group (relative risk compared with placebo, 0.87; 95% CI, 0.59-1.30) and 29.3% in the E purpurea group (relative risk compared with placebo, 0.80; 95% CI, 0.53-1.31) had an infection. Participants in the treatment groups believed that they had more benefit from the medication than those in the placebo group (P = .04). Adverse effects were reported by 18 subjects in the E angustifolia group, 10 in the E purpurea group, and 11 in the placebo group. CONCLUSION: In this study a prophylactic effect of the investigated echinacea extracts could not be shown. However, based on the results of this and 2 other studies, one could speculate that there might be an effect of echinacea products in the order of magnitude of 10% to 20% relative risk reduction. Future studies with much larger sample sizes would be needed to prove this effect.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Int J Immunopharmacol. 1997 Jul;19(7):371-9.

Echinacea purpurea, a plant originally used by native Americans to treat respiratory infections, was evaluated for its ability to stimulate the production of cytokines by normal human peripheral blood macrophages in vitro. Commercial preparations of echinacea fresh pressed juice and dried juice were tested at concentrations ranging from 10 micrograms/ml to 0.012 microgram/ml and compared to endotoxin stimulated and unstimulated controls. Cytokine production was measured by ELISA after 18 h of incubation for IL-1 and 36 and 72 h for TNF-alpha, IL-6, and IL-10. Macrophages cultured in concentrations of echinacea as low as 0.012 microgram/ml produced significantly higher levels of IL-1, TNF-alpha, IL-6 and IL-10 (P < 0.05) than unstimulated cells. The high levels of IL-1, TNF-alpha, and IL-10 induced by very low levels of echinacea are consistent with an immune activated antiviral effect. Echinacea induced lower levels of IL- 6 in comparison to the other cytokines measured. These results demonstrate the immune stimulatory ability of the unpurified fresh pressed juice of Echinacea purpurea and offer some insight into the nature of the resulting immune response as compared to endotoxin.

J Altern Complement Med. 1995 Summer;1(2):145-60.

Results of five randomized studies on the immunomodulatory activity of preparations of Echinacea.

Melchart D, Linde K, Worku F, Sarkady L, Holzmann M, Jurcic K, Wagner H.
Projekt Munchener Modell, Ludwig-Maximilians-Universitat Munchen, Germany.

This article describes and discusses five placebo-controlled randomized studies investigating the immunomodulatory activity of preparations containing extracts of Echinacea in healthy volunteers. A total of 134 (18 female and 116 male) healthy volunteers between 18 and 40 years of age were studied. Two studies tested intravenous homeopathic complex preparations containing Echinacea angustifolia D1 (study 1) and D4 (study 5). Two studies (2 and 3a) tested oral alcoholic extracts of roots of E. purpurea, one study an extract of E. pallida roots (study 3b), and one study an extract of E. purpurea herb (study 4). Test and placebo preparations were applied for four (study 5) or five (studies 1-4) consecutive days. The primary outcome measure for immunomodulatory activity was the relative phagocytic activity of polymorphonuclear neutrophil granulocytes (PNG), measured in studies 1 and 2 with a microscopic method and in studies 3, 4, and 5 with two different cytometric methods. The secondary outcome measure was the number of leukocytes in peripheral venous blood. Safety was assessed by a screening program of blood and other objective parameters as well as by documentation of all subjective side effects. In studies 1 and 2 the phagocytic activity of PNG was significantly enhanced compared with placebo [maximal stimulation 22.7% (95% confidence interval 17.5-27.9%) and 54.0% (8.4-99.6%), respectively], while in the other studies no significant effects were observed. Analysis of intragroup differences revealed significant changes in phagocytic activity during the observation periods in five test and three control groups. Leukocyte number was not influenced significantly in any study. Side effects due to the test preparations could not be detected. Our studies provide evidence for immunomodulatory activity of the homeopathic combination tested in study 1 and the E. purpureae radix extract tested in study 2. The negative results of the other three studies are difficult to interpret due to the different methods for measuring phagocytosis, the relevant changes in phagocytic activity within most placebo and treatment groups during the observation period, and the small sample sizes. Future studies should be performed on patients rather than healthy volunteers and use standardized or chemically defined monopreparations of Echinacea.

Publication Types:

•  Clinical Trial

•  Randomized Controlled Trial

Immunopharmacology. 1997 Jan;35(3):229-35.

In vitro effects of echinacea and ginseng on natural killer and antibody-dependent cell cytotoxicity in healthy subjects and chronic fatigue syndrome or acquired immunodeficiency syndrome patients.

See DM, Broumand N, Sahl L. Department of Medicine, U.C. Irvine Medical Center , Orange , USA .

Extracts of Echinacea purpurea and Panax ginseng were evaluated for their capacity to stimulate cellular immune function by peripheral blood mononuclear cells (PBMC) from normal individuals and patients with either the chronic fatigue syndrome or the acquired immunodeficiency syndrome. PBMC isolated on a Ficoll-hypaque density gradient were tested in the presence or absence of varying concentrations of each extract for natural killer (NK) cell activity versus K562 cells and antibody-dependent cellular cytotoxicity (ADCC) against human herpesvirus 6 infected H9 cells. Both echinacea and ginseng, at concentrations > or = 0.1 or 10 micrograms/kg, respectively, significantly enhanced NK-function of all groups. Similarly, the addition of either herb significantly increased ADCC of PBMC from all subject groups. Thus, extracts of Echinacea purpurea and Panax ginseng enhance cellular immune function of PBMC both from normal individuals and patients with depressed cellular immunity.

Z Arztl Fortbild (Jena). 1996 Apr;90(2):111-5.

[Echinacea drugs--effects and active ingredients]

Bauer R. Institut fur Pharmazeutische Biologie der Heinrich-Heine-Universitat, Dusseldorf.

Echinacea-containing drugs have to be classified according to the used plant species (Echinacea purpurea, E. pallida or E. angustifolia), the processed part of the plant (root, upper parts or whole plant), and the mode of processing. Significant pharmacological effects have been found in vitro and in vivo for the expressed juice of the upper parts of E. purpurea and for alcoholic extracts of the roots of E. pallida, E. angustifolia and E. purpurea. The activity is mainly directed towards the nonspecific cellular immune system. Several active constituents are discussed: polysaccharides, glycoproteins, caffeic acid derivatives (cichoric acid) and alkamides.

Publication Types:

•  Review

•  Review, Tutorial

J Clin Lab Anal. 1996;10(6):441-5.

We measured the levels of the cytokines IL-1-alpha, IL-1-beta, IL-2, IL-6, TNF-alpha, and IFN-gamma in culture supernatants of stimulated whole blood cells derived from 23 tumor patients undergoing a 4-week oral treatment with a spagyric extract from Echinacea angustifolia, Eupatorium perfoliatum, and Thuja occidentalis (Echinacea complex). All patients had had curative surgery for a localized solid malignant tumor. Blood was taken before treatment and after 2 and 4 weeks of therapy. Twelve untreated tumor patients at the same clinical stage, also after curative surgery, served as a control group. In the blood cell cultures of all patients, a rather wide range of cytokine levels was found. After therapy with Echinacea complex, no significant alteration in the production of the cytokines could be seen in comparison to the controls, and also the leukocyte populations remained constant. We conclude that at this application and dosage, the therapy with Echinacea complex has no detectable effect on tumor patients' lymphocytes activity as measured by their cytokine production.

Planta Med. 1995 Dec;61(6):510-4.

The protective effect of caffeoyl derivatives (echinacoside, chlorogenic acid, chicoric acid, cynarine, and caffeic acid, typical constituents of Echinacea species) on the free radical-induced degradation of Type III collagen has been investigated. The macromolecule was exposed to a flux of oxygen radicals (superoxide anion and hydroxyl radical) generated by the xanthine/xanthine oxidase/Fe2+/EDTA system and its degradation assessed qualitatively by SDS-PAGE and quantitatively as the amount of soluble peptides (according to the 4-hydroxyproline method) released from native collagen after oxidative stress. The SDS-PAGE pattern of native collagen is markedly modified by free radical attack, with formation of a great number of peptide fragments with molecular masses below 97 kDa: in the presence of microM concentrations of echinacoside, there is a complete recovery of the native profile. Collagen degradation was, in fact, dose-dependently inhibited by all the compounds, with the following order of potency: echinacoside approximately chicoric acid > cynarine approximately caffeic acid > chlorogenic acid, with IC50 ranging from 15 to 90 microM. These results indicate that this representative class of polyphenols of Echinacea species protects collagen from free radical damage through a scavenging effect on reactive oxygen species and/or C-, N-, S-centered secondary radicals, and provide an indication for the topical use of extracts from Echinacea species for the prevention/treatment of photodamage of the skin by UVA/UVB radiation, in which oxidative stress plays a crucial role.

Planta Med. 1994 Feb;60(1):37-40.

Polyunsaturated alkamides isolated from Achillea species, Echinacea angustifolia DC., Anacyclus pyrethrum (L.) Link, and Aaronsohnia pubescens (Desf.) Bremer & Humphries, (Compositae) were shown to possess inhibitory activity in in vitro cyclooxygenase (sheep seminal microsomes) and 5-lipoxygenase (porcine leukocytes) assays. Activity appeared to depend on the particular structure of the alkamides.

Farmaco. 1993 Oct;48(10):1447-61.

Direct characterization of caffeoyl esters with antihyaluronidase activity in crude extracts from Echinacea angustifolia roots by fast atom bombardment tandem mass spectrometry.

Facino RM, Carini M, Aldini G. Istituto di Chimica Farmaceutica e Tossicologica, Milan, Italy.

Fast atom bombardment (FAB-MS) and fast atom bombardment tandem mass spectrometry (FAB-MS/MS) techniques (negative ions) have been successfully applied for identification of the constituents responsible for the antihyaluronidase activity of Echinacea angustifolia roots, whose extracts are widely employed for the adjuvant therapy of chronic inflammatory diseases. Crude extracts from different solvents were tested for antihyaluronidase activity, and those with the greatest inhibitory action (the ethylacetate, butylacetate and chloroform fractions, IC50 0.44, 0.50 e 0.62 mg/ml) were directly analyzed by MS. Full scan mass spectra produced intense molecular anions: collisional activation of these resulted in tandem mass spectra rich in significant product ions. Four main caffeoyl conjugates were detected and identified by tandem mass spectrometry (daughter and parent ion mode): 2,3-O-dicaffeoyltartaric acid (chicoric acid) and 5-O-dicaffeoylquinic acid (cynarine) and 2-O-caffeoyltartaric acid (caffaric acid) in the ethylacetate fraction. Among these caffeoyl conjugates, chicoric and caftaric acids had the greatest antihyaluronidase activity: IC50 = 0.42 and 0.61 mM , while the IC50 of cynarine and chlorogenic acid were 1.85 and 2.25 mM .

Cesk Farm. 1993 Aug;42(4):184-7.

Int J Immunopharmacol. 1993 Jul;15(5):605-14.

Polysaccharides (EP) isolated from large scale plant cell cultures of Echinacea purpurea, have been shown to activate human and murine phagocytes. In this study we investigated the influence of EP on the nonspecific immunity in immunodeficient mice. EP was effective in activating peritoneal macrophages isolated from animals after administration of cyclophosphamide (CP) or cyclosporin A (CsA). EP-treated macrophages exhibited increased production of tumor necrosis factor-alpha (TNF) and enhanced cytotoxicity against tumor target WEHI 164 as well as against the intracellular parasite Leishmania enrietti. After a CP-mediated reduction of leukocytes in the peripheral blood, the polysaccharides induced an earlier influx of neutrophil granulocytes as compared to PBS-treated controls. EP treatment of mice, immunosuppressed with CP or CsA, restored their resistance against lethal infections with the predominantly macrophage-dependent pathogen Listeria monocytogenes and predominantly granulocyte-dependent Candida albicans. Further, the effects of EP in allogeneic bone marrow chimeric mice are discussed. These findings may have therapeutical implications in prophylactic treatment of opportunistic infections.

Planta Med. 1992 Apr;58(2):163-5.

Studies on antigen specifity of immunoreactive arabinogalactan proteins extracted from Baptisia tinctoria and Echinacea purpurea.

Egert D, Beuscher N. Schaper & Brummer, Salzgitter , Federal Republic of Germany .

In a series of experiments the cross-reactivity of antibodies raised against arabinogalactan proteins from Baptisia tinctoria and Echinacea purpurea was studied in order to prove the antigen specificity of the extracted glycoproteins/polysaccharides. Using the antigen-antibody reaction in a competitive ELISA it was evident that antibodies against glycoproteins from Baptisia tinctoria were specific because none of the other antigens like those from Echinacea purpurea, Thuja occidentalis, arabinogalactan from larch, LPS from E. coli 055:B5, and from Salmonella typhimurium were able to inhibit the antigen-antibody reaction. The same results were obtained from ELISA experiments with Echinacea purpurea. From these studies it was concluded that the antigenic regions of immunoreactive proteins from both medicinal plants show structural differences.

Cancer Invest. 1992;10(5):343-8.

Nonspecific immunostimulation with low doses of cyclophosphamide (LDCY), thymostimulin, and Echinacea purpurea extracts (echinacin) in patients with far advanced colorectal cancers: preliminary results.

Lersch C, Zeuner M, Bauer A, Siemens M, Hart R, Drescher M, Fink U, Dancygier H.

Kliniken und Polikliniken der Technischen, Universitat Munchen , Germany .

Outpatients (n = 15) with metastasizing far advanced colorectal cancers received immunotherapy consisting of low-dose cyclophosphamide (LDCY) 300 mg/m2 every 28 days i.v., thymostimulin 30 mg/m2, days 3-10 after low-dose cyclophosphamide i.m. once daily, then twice a week, and echinacin 60 mg/m2 together with thymostimulin i.m. All patients had had previous surgery and/or chemotherapy and had progressive disease upon entering the study. Two months after onset of therapy a partial tumor regression was documented in one and a stable disease in 6 other patients by abdominal ultrasonography, decrease of the tumor markers carcinoembryonic antigen (CEA), CA 19-9, CA 15-3, and/or chest roentgenography, which may also be attributed to the natural course of disease. Mean survival time was 4 months, 2 patients survived for more than 8 months. Immunotherapy was well tolerated by all patients without side effects.

Publication Types:

•  Clinical Trial

Arzneimittelforschung. 1991 Oct;41(10):1076-81.

Planta Med. 1991 Oct;57(5):447-9.

The constituents of the roots of Echinacea simulata and E. paradoxa were examined by HPLC. The major lipophilic and hydrophilic compounds could be identified. E. paradoxa contained several ketoalkenynes and proved to have almost identical constituents as E. pallida. E. simulata contained alkamides as found in E. angustifolia and in addition ketoalkenynes as in E. pallida. Echinacoside was found in both species.

Int J Immunopharmacol. 1991;13(1):27-37.

Purified polysaccharides from cell cultures of the plant Echinacea purpurea were investigated for their ability to enhance phagocytes' activities regarding nonspecific immunity in vitro and in vivo. Macrophages (M phi) from different organ origin could be activated to produce IL-1, TNF alpha and IL-6, to produce elevated amounts of reactive oxygen intermediates and to inhibit growth of Candida albicans in vitro. Furthermore, in vivo the substances could induce increased proliferation of phagocytes in spleen and bone marrow and migration of granulocytes to the peripheral blood. These effects indeed resulted in excellent protection of mice against the consequences of lethal infections with one predominantly M phi dependent and one predominantly granulocyte dependent pathogen, Listeria monocytogenes and C. albicans, respectively. Specific immune responses to sheep red blood cells (antibody production) and to listeria (DTH) were not affected by the polysaccharides. The possibility of clinical use is discussed.

Int J Immunopharmacol. 1991;13(7):931-41.

Application of purified polysaccharides from cell cultures of the plant Echinacea purpurea to test subjects mediates activation of the phagocyte system.

Roesler J, Emmendorffer A, Steinmuller C. Fraunhofer Institute, Department of Immunobiology, Hannover , F.R.G.

Polysaccharides purified from large-scale cell cultures of the plant Echinacea purpurea were tested for their ability to activate human phagocytes in vitro and in vivo. These substances enhanced the spontaneous motility of PMN under soft agar and increased the ability of these cells to kill staphylococci. Monocytes were activated to secrete TNF-alpha, IL-6 and IL-1 whereas class II expression was unaffected. Intravenous application of the polysaccharides to test subjects immediately induced a fall in the number of PMN in the peripheral blood, indicating activation of adherence to endothelial cells. This fall was followed by a leukocytosis due to an increase in the number of PMN and a lesser increase of monocytes. The appearance of stab cells and some juvenile forms and even myelocytes indicated the migration of cells from the bone marrow into the peripheral blood. The acute phase C-reactive protein (CRP) was induced, probably due to activation of monocytes and macrophages to produce IL- 6. In addition a moderate acceleration of the erythrocyte sedimentation rate was observed. Altogether, as in mice, the polysaccharides could induce acute phase reactions and activation of phagocytes in humans. The possibility of clinical use is discussed.

Arch Geschwulstforsch. 1990;60(5):379-83.

Stimulation of the immune response in outpatients with hepatocellular carcinomas by low doses of cyclophosphamide (LDCY), echinacea purpurea extracts (Echinacin) and thymostimulin.

Lersch C, Zeuner M, Bauer A. II. Department of Internal Medicine, Technical University of Munich , FRG.

Outpatients with inoperable far advanced hepato-cellular carcinomas (n = 5) were treated with LDCY--300 mg/m2 i.v. every 28 days-, echinacin--60 mg/m2 i.m.--and thymostimulin--30 mg/m2 i.m., day 3-10 after LDCY, then twice a week. Therapy was well tolerated by all patients. Their Karnofsky' index increased for 10% in the mean. A stable disease for more than 8 weeks was documented by abdominal ultrasonography in one patient. Serum levels of Alpha-Fetoprotein (AFP), Carcinoembryonic Antigen (CEA) and Tissue Polypeptide Antigen (TPA) did not increase in 2 patients. Median survival time was 2.5 months. One patient is still alive after 8 months. Absolute numbers of CD8+ cells significantly (p less than 0.02) decreased for 7% 1 day after LDCY, whereas CD4+ cells increased (p less than 0.02) from day 1-7. Numbers of natural killer (NK-) cells increased for 17% (p less than 0.05), their activity for 90% (p less than 0.05). Activities of peripheral polymorphs (p less than 0.05) increased for 27% and of Lymphokine Activated Killer (LAK-) cells for 180% (p less than 0.05).

Zentralbl Veterinarmed B. 1989 Jul;36(5):353-64.

J Natl Cancer Inst. 1989 May 3;81(9):669-75.

Macrophage activation by the polysaccharide arabinogalactan isolated from plant cell cultures of Echinacea purpurea.

Luettig B. Fraunhofer Institute fur Toxikologie, Abt. Immunbiologie, Hannover , Federal Republic of Germany.

In this study, acidic arabinogalactan, a highly purified polysaccharide from plant cell cultures of Echinacea purpurea, with a molecular weight of 75,000, was effective in activating macrophages to cytotoxicity against tumor cells and micro-organisms (Leishmania enriettii). Furthermore, this polysaccharide induced macrophages to produce tumor necrosis factor (TNF-alpha), interleukin-1 (IL-1), and interferon-beta 2. Arabinogalactan did not activate B cells and did not induce T cells to produce interleukin-2, interferon-beta 2, or interferon-gamma, but it did induce a slight increase in T-cell proliferation. When injected ip, this agent stimulated macrophages, a finding that may have therapeutic implications in the defense against tumors and infectious diseases.

Pharmacol Res Commun. 1988 Dec;20 Suppl 5:87-90.

Anti-inflammatory activity of Echinacea angustifolia fractions separated on the basis of molecular weight.

Tragni E, Galli CL, Tubaro A. Institute of Pharmacological Sciences, University of Milan , Italy .

Five fractions of an aqueous extract obtained from the roots of Echinacea angustifolia were separated on the basis of molecular weight. The topical anti-inflammatory activity of the fractions has been evaluated in mice using the Croton oil ear test. The fraction with a molecular weight between 30,000 and 100,000 was the most active in inhibiting the oedema; it also reduced the infiltration of inflammatory cells. The activity of this fraction was comparable with that of a raw polysaccharidic extract obtained from E. angustifolia roots by differential solubility. The high-molecular weight polysaccharides are therefore proposed as the anti-inflammatory principles of the plant.

Arzneimittelforschung. 1988 Feb;38(2):276-81.

J Pharm Pharmacol. 1987 Jul;39(7):567-9.

The anti-inflammatory activity of a polysaccharidic fraction (EPF) obtained from Echinacea angustifolia roots has been examined using the carrageenan paw oedema and the croton oil ear test. EPF (0.5 mg kg-1 i.v.) almost inhibited the carrageenan-induced oedema over 8 h and furthermore, EPF, topically applied, inhibited mouse ear oedema induced by croton oil. EPF also reduced the leukocytic infiltration of the croton oil dermatitis, evaluated both as peroxidase activity and histologically. After topical application EPF appears to be slightly inferior in potency to indomethacin. The results suggest that the anti-inflammatory activity of E. angustifolia resides in its polysaccharidic content.

Onkologie. 1987 Jun;10(3 Suppl):27-33.

Extracts of Viscum album (Plenosol) and Echinacea purpurea (Echinacin) are used clinically for their non-specific action on cell-mediated immunity. In vitro we could prove that these two extracts have a stimulating effect on the production of lymphokines by lymphocytes and in the transformation test. A toxic effect on cells was produced only with very high, clinically irrelevant concentrations. Clinical application of these extracts can produce a stimulation of cell-mediated immunity (one therapeutic administration followed by a free interval of one week) or can have a depressive action (daily administrations of higher doses). These observations were confirmed by lymphokine production and assay, 3H-thymidine incorporation and a skin test with recall antigens (Multitest Merieux).

Infect Immun. 1984 Dec;46(3):845-9.

Macrophage activation and induction of macrophage cytotoxicity by purified polysaccharide fractions from the plant Echinacea purpurea.

Stimpel M, Proksch A, Wagner H, Lohmann-Matthes ML.

Purified polysaccharides (EPS) prepared from the plant Echinacea purpurea are shown to strongly activate macrophages. Macrophages activated with these substances develop pronounced extracellular cytotoxicity against tumor targets. The activation is brought about by EPS alone and is independent of any cooperative effect with lymphocytes. Also the production and secretion of oxygen radicals and interleukin 1 by macrophages is increased after activation with EPS. Cells of the macrophages lineage seem to be the main target for the action of these polysaccharides. EPS has no effect on T lymphocytes. B lymphocytes show a comparatively modest proliferation after incubation with E. purpurea EPS. Thus, these compounds, which are at least in tissue culture completely nontoxic, may be suited to activate in vivo cells of the macrophage system to cytotoxicity. They may therefore be of relevance in tumor and infectious systems.