What Is Echinacea Used For?

Echinacea, a genus of perennial herbaceous plants in the family Asteraceae. Plants 50–150 cm tall, with ovate leaves with coarse teeth, many branches, root conical, flowers purple to purplish red. Echinacea is native to the Americas and has a total of eight species and several varieties. Currently, three varieties are available as medicines: Echinacea purpurea (commonly known as purple coneflower), Echinacea augusti folia (narrow-leaved purple coneflower) and Echinacea pallida (white coneflower). Echinacea is currently an immune regulator that is attracting international attention. Its preparations are among the top 5 best-selling products in the pharmaceutical markets of Europe and the United States. It is a world-famous “immune” herb with outstanding anti-infective and immunomodulatory effects, and has attracted great attention at home and abroad. Echinacea was introduced to China as a flower in the 1970s, and in the 1990s it began to be cultivated as a medicinal plant in various parts of the country. In June 2012, Echinacea and its preparations were approved by the Ministry of Agriculture as a new national Class I veterinary drug. Studies have shown that Echinacea has a significant immunostimulatory effect on animals.

1 Chemical composition of Echinacea extract

At present, a variety of compounds can be isolated from Echinacea, including essential oils, polyacetylenes, caffeic acid and its derivatives, polysaccharides and glycoproteins, alkylamides, alkaloids, steroids, flavonoids, lipids, etc., among which polyphenols, essential oils, and lipids are the most abundant. Echinacea roots, stems, leaves and flowers all contain polyphenols and sugars. The leaves and flowers have a higher content of polyphenols, while the roots and stems have a higher content of sugars.

1.1 Polysaccharides and glycoproteins

The highest content of polysaccharides isolated from Echinacea purpurea is inulin. Other polysaccharides include xyloglucan, pectin-like polysaccharides, 4-methoxyl-glucurono-arabino-xylan, acidic arabinogalactan, fructan, and inulin. Three glycoproteins containing arabinose, galactose, and glucuramine can also be isolated from Echinacea purpurea.

1.2 Caffeic acid and its derivatives

Echinacea is rich in caffeic acid substances, which are the main active ingredients. Caffeic acid, methyl caffeate, ethyl caffeate, chicoric acid, chlorogenic acid, echinacoside, caffeoyl tartaric acid and cinnamic acid can be isolated using solvent extraction and chromatography. The main phenolic compounds in echinacea are chicoric acid, caffeoyl tartaric acid and echinacoside. The American Herbal Pharmacopoeia (AHP) uses the HPLC method developed by the Institute for Nutraceutical Advancement (IN A) to determine the total phenolic content of echinacea and quantitatively study the phenolic components in echinacea (mainly caffeoyl tartaric acid, chlorogenic acid, echinacoside, thujaplicin and chicoric acid).

1.3 Essential oil

Echinacea purpurea was analyzed by GC-MS and 68 compounds were initially identified. The essential oil of Echinacea purpurea contains fatty acids, unsaturated fatty acids and their esters. The main compounds are n-hexadecanoic acid,  octadecanoic acid, methyl 9,12-linoleate, methyl 9,12,15-linolenate, 9,12-linoleic acid, ethyl 9,12-linoleate, methyl 14-methylpentadecanoate, etc. The alkenes include terpene compounds such as monoterpenes and sesquiterpenes, as well as oxygen-containing compounds. Among these, 1,11-dodecadiene, 1-methyl-5-methylene-8-(1-methylethyl)-1,6-cyclodecadiene, 1-tridecene, caryophyllene, and a-zihydro-chamazulene have relatively high relative contents. aromatic hydrocarbon derivatives mainly include 1,2,3,5,6,8α-hexahydro-4,7-dimethyl-1-(1-methylethyl)-naphthalene and  1,2,3,4,4a,5,6,8α-octahydro-7-methyl-4-methylene-1-(1-methylethyl)-(1α,4α β,8α α)-naphthalene, etc.; alcohols include the typical compounds of angelica alcohol, α-Juniperol, Molerol, 1-Hexadecanol and other typical compounds; in addition, it also contains many heterocyclic compounds and other substances with relatively low content.

1.4 Other compounds

Echinacea also contains acetic acid, 1-methyl-3-(1-methylethyl)benzene, 2-butanone-3-hydroxy, 2,3-butanediol, 2-methylpropanoic acid, 7,8-furocoumarin and 6-methoxy-7-hydroxycoumarin. It also contains two alkaloids, colchicine and isocolchicine, the steroidal compounds stigmasterol and β-sitosterol, as well as 15 inorganic elements and 16 amino acids, eight of which are essential to the human body.

2 Echinacea's immunomodulatory effect in animals

2.1 Echinacea's effect on chicken diseases

2.1.1 Efficacy of Echinacea against Newcastle disease virus

Newcastle disease is a highly contagious and acute septic disease caused by the ND virus. It is one of the most harmful and economically devastating diseases in China's poultry industry, with a morbidity and mortality rate of over 90%. Echinacea has antiviral effects and strong immune-enhancing properties. Echinacea extract has a strengthening effect on the humoral immune system in chickens. The protective effect of Echinacea injection and control solution on chicken embryos infected with Newcastle disease virus was determined by chicken embryo culture method and hemagglutination test. The results showed that natural medicine Echinacea injection had no toxic effect on chicken embryos, it could improve the survival rate of ND V-infected chicken embryos and reduce the HA titer of ND V-infected chicken embryos. Echinacea extract can significantly inhibit the proliferation of chicken Newcastle disease virus and reduce the mortality of chicken embryos. By adopting the method of random grouping and pathological model replication, it was shown that the high and medium dose groups of the echinacea complex were superior to the control group and the low dose group of the echinacea complex in terms of both protection rate and efficacy, and were also slightly superior to the vaccine control group. It has a significant preventive and protective effect on chicks infected with the newcastle disease virus, and can be used for the prevention and treatment of newcastle disease.

2.1.2 Efficacy of Echinacea against the fowl cholera virus

Fowl cholera is an acute, highly contagious disease caused by the IB DV virus. Once infected, it can cause serious economic losses in the poultry industry. Observations of artificially infected infectious bursal disease virus with echinacea complex showed that it can reduce the damage of IB DV to the immune organs of chicks. It has a significant protective effect against highly virulent infectious bursal disease infection, and the protective effect on bursal atrophy caused by bursal virus infection is also significant.

Echinacea and astragalus mixture can significantly reduce the damage caused by infectious bursal virus to the liver and promote the activity of NK cells in the spleen for a period of time around 12 days after the chicks are infected with IB DV. After the application of Echinacea and Astragalus, the number of CD4+ T lymphocytes in the thymus, bursa of Fabricius and intestinal epithelial lamina propria increased significantly (p<0.05), and the number of B lymphocytes recovered to a certain extent, indicating that the active substances in Echinacea and Astragalus can to some extent reduce or block the proliferation of IB DV in the body and exert an immunomodulatory effect. In vitro, low concentrations of Echinacea polysaccharides can help increase the transformation rate of T lymphocytes in chicken spleens by assisting with concanavalin A, promote the proliferation of T lymphocytes, increase the transformation rate of B lymphocytes in chicken spleens, and enhance humoral immune function. After taking Echinacea, the globulin content increased significantly 11 days after the virus was introduced, which can relieve immunosuppression and regulate the body's immune function. Echinacea can therefore enhance the body's defence function and has a significant effect on the prevention and treatment of fowl pox.

2.1.3 Echinacea's effect on avian influenza

Avian influenza is a highly infectious disease caused by avian influenza virus (AIV) that mainly affects chickens. Highly pathogenic strains can cause sudden death in poultry and can also infect humans. At present, avian influenza occurs in many countries and regions around the world, causing huge economic losses to the poultry industry. The efficacy of the avian influenza vaccine in broilers was measured by ELISA and the hemagglutination inhibition test (HI), and it was found that Echinacea can enhance the efficiency of the influenza vaccine, and Echinacea extract can be used for the prevention of avian influenza.

2.1.4 Effect of Echinacea compound on laying hens under high temperatures

Chickens do not have sweat glands, have a high body temperature and a vigorous metabolism. In summer, the high temperatures and humidity in most parts of China often cause significant heat stress in livestock and poultry. Studies have reported that 1% and 1.5% echinacea compound can both increase feed intake, egg production rate and average daily egg production, reduce the feed-to-egg ratio, the ratio of soft-broken eggs and the number of mortalities, and significantly improve the production performance of laying hens under high temperature conditions. Echinacea compounds at different concentrations can all increase the serum concentrations of G LU, TP, and ALB and the activity of ALP, and reduce the serum levels of TG and CHO and the activities of ALT and CK. Under heat stress, the activities of SOD and G SH-Px in the liver tissue of laying hens decreased significantly (p<0.05), and the content of MDA increased significantly (p<0.05). Echinacea complex can increase the activity of SOD and GSH-Px in liver tissue and reduce the content of MDA in liver tissue. Echinacea complex can promote the recovery and improvement of the antioxidant function of the liver tissue of laying hens under heat stress, and can be used in summer to reduce heat stress in laying hens.

2.2 The effect of echinacea on mouse immunity

Echinacea extract can effectively increase the weight of the spleen in mice, increase the level of immunoglobulin in the serum and lower the level of total cholesterol, enhancing resistance to pathogens. It has the function of improving immunity and lowering blood lipids. After mice were orally administered a mixture of echinacea and levamisole, there was a significant increase in globulin levels, neutrophils and macrophage phagocytic activity, and the synergistic effect increased. Echinacea extract can enhance the immunity of mice.

2.3 The effect of echinacea on cow immunity

Peripheral blood mononuclear cell proliferation is the most direct indicator of the body's cellular immune function. Early-pregnant Holstein cows were used as test animals, and the effects of Echinacea purpurea extracts of different concentrations on the proliferation of peripheral blood mononuclear cells (PBMC) in vitro were detected using the ELISA method in combination with Con A and PWM. The results showed that Echinacea purpurea extracts at different concentrations could promote the proliferation of PBMC from normal cows, and that Echinacea purpurea extracts at different concentrations combined with Con A could inhibit PBMC proliferation. Echinacea purpurea extract combined with PWM can significantly stimulate PBMC proliferation, and the proliferation of bovine peripheral blood mononuclear cells in response to Echinacea purpurea extract is dose-dependent. Echinacea purpurea extract can induce the production of IFN-γ by bovine peripheral blood lymphocytes, but there is no significant effect between different concentrations (p<0.05).

2.4 The effect of Echinacea compound preparations on the production performance and immune function of Yunling black goats

Adding a compound echinacea extract to the feed can increase the number of white blood cells in the blood of Yunling black goats, thereby enhancing the immune function of white blood cells against the body; it can also significantly increase the number of red blood cells and the hematocrit in the blood, and promote the hematopoietic function and immunity of Yunling black goats. Echinacea extract can increase the total protein and globulin content in the serum of Yunling black goats. Adding echinacea to the feed has no adverse effect on the body's material metabolism and can reduce the cholesterol content in the blood. Compound echinacea extract has a significant weight gain effect on Yunling black goats. Adding compound echinacea extract to the feed can improve the production performance and blood physiological and biochemical indicators of Yunling black goats, enhance immunity, and improve the economic benefits of raising goats. It can be widely promoted in production.

2.5 Effects of Echinacea purpurea extract on aquatic animals

Echinacea purpurea extract significantly increased the relative weight gain rate of Pengze crucian carp (P<0.05), significantly reduced the hydroxyl radicals in the carp serum (P<0.05), reduced malondialdehyde (MDA) content, and increased the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) activity, while also reducing glutathione peroxidase (GSH-Px) activity, enhancing the antioxidant response of the serum of Pengze crucian carp. A study of the effect of Echinacea purpurea on the growth of Nile tilapia found that in the summer, Echinacea purpurea can significantly increase the body weight gain and growth rate of tilapia, and can significantly improve the survival rate of the fish. When Echinacea purpurea was added to rainbow trout feed, the body weight gain and specific growth rate of rainbow trout in each Echinacea purpurea-added group were improved, blood and blood biochemical indicators were improved, the feed conversion ratio was reduced, and the 0.5% addition had the best effect. Adding Echinacea purpurea can increase the body weight gain and anti-infection ability of guppies and increase the amino acid content in their bodies.

3 Echinacea toxicity

Echinacea extract was tested in the Salmonella typhimurium reverse mutation assay (Ames test), and it was found that it does not cause an increase in the number of reverse mutations in Salmonella typhimurium, indicating that it is not genotoxic. Echinacea was administered orally, and after killing the mice, the bone spines were taken and sections were made. Micronuclei were observed under the oil lens, and the micronucleus rate was calculated. The results showed that the echinacea extract had no effect on the micronucleus rate of mouse bone marrow cells, and the result was negative, indicating that the drug has no mutagenic effect.

In summary, Echinacea has an immunomodulatory effect, and foreign research has shown that it also has anti-inflammatory, antibacterial, antiviral, antitumor and tissue regeneration effects. Echinacea extract has been widely used in clinical settings abroad as an immunomodulator and immunostimulant. Echinacea can replace antibiotics to some extent, and can solve the problem of the transfer of drug resistance caused by the long-term use of antibiotics in animals. It is a natural antibiotic and can be used as a green feed additive. Currently, domestic research on the pharmacological activity of echinacea mainly focuses on the immune level. All walks of life need to invest more financial and material resources to study its comprehensive pharmacological activity and clinical application, so as to provide strong conditions for the research and development of echinacea in China and enable echinacea to be widely promoted in production.