Echinacosides

In addition to chemotype patterning revealed by statistical analysis of the data, latitudinal relationships emerged as well. Concentrations of cichoric acid and echinacoside and one of the amides, undeca-2Z,4Z-diene-8,10-diynoic acid 2-methylbutyl amide [246], with a larger amine-bearing group increased with latitude. The inverse relationship was observed for caftaric acid and hexadeca-2 , 9Z-diene-12,14-diynoic acid isobutylamide. The latitudinal differences may be of importance in helping to identify populations for selection of seed for propagation. 

The purple coneflower Echinacea purpura, and its close relatives, E. angustifolia and E. pallida, are the source of the herb Echinacea, which is widely popular as a nonspecific immune stimulant. These perennials are native to the prairies of North America and are now widely grown garden ornamentals. The root and aerial parts of the plant are the portions used, and the preparation s potency can be verified by the transient tingling sensation produced when it is tasted. Echinacea contains alkamides, caffeic acid esters (echinacoside, cichoric acid, caftaric acid), polysaccharides (heteroxylan), and an essential oil. Some echinacea products are standardized for their echinacoside content. In the past, adulteration with American feverfew (Parthenium integri-folium) was common. Echinacea is now sold either by itself or in combination with golden seal or zinc for the treatment of colds and influenza. 

Standardized to 4% echinacosides. TsID, no inhibitory activity detected. 

The three most widely used species of Echinacea are Echinacea purpurea, E pallida, and E angustifolia. The chemical constituents include flavonoids, lipophilic constituents (eg, alkamides, polyacetylenes), water-soluble polysaccharides, and water-soluble caffeoyl conjugates (eg, echinacoside, chicoric acid, caffeic acid). Within any marketed echinacea formulation, the relative amounts of these components are dependent upon the species used, the method of manufacture, and the plant parts used. Epurpurea has been the most widely studied in clinical trials. Although the active constituents of echinacea are not completely known, chicoric acid from E purpurea and echinacoside from E pallida and E angustifolia, as well as alkamides and polysaccharides, are most often noted as having immune-modulating properties. Most commercial formulations, however, are not standardized for any particular constituent. 

A qualitative determination of the CAP in E. pallida showed that the roots contain high echinacoside levels whereas, cichoric acid was the predominant CAP in the flowers and leaves (Cheminat et al., 1988). This qualitative evaluation is a reasonable approximation of the CAP distribution in plant tissue however, the level of the individual CAP is dictated by the Echinacea species evaluated. Pietta et al. (1998) presented a qualitative evaluation on the CAP in E. purpurea, E. pallida and E. angustifolia using micellar electrokinetic chromatography (MEKC). These authors noted that echinacoside was present in the roots and aerial parts of the E. pallida and E. angustifolia, but not E. purpurea. Cichoric acid is the predominant CAP in E. purpurea roots and aerial parts but is virtually absent in all parts of E. angustifolia and roots of E. pallida. The presence of other CAP in plant tissues is variable and species-variety-dependent (Tables III-V). 

COMPARISON BETWEEN SOXHLET AND ULTRASOUND-PROMOTED EXTRACTION OF CICHORIC ACID AND ECHINACOSIDE FROM E. PURPUREA AND E. ANGUSTIFOLIA, RESPECTIVELY... 

Extraction condition E. angustifolia roots Echinacoside E. purpurea root Cichoric acid E. purpurea top Cichoric acid... 

Facino, R.M., Carini, M., Aldini, G., Saibene, L., Pietta, P., and Mauri, P. 1995. Echinacoside and caffeoyl conjugates protect collagen from free radical-induced degradation a potential use of Echinacea extracts in the prevention of skin photodamage. Planta Med. 61, 510-514. 

Schulz, H., Pfeffer, S., Quilitzsch, R., Steuer, B., and Reif, K. 2002. Rapid and non-destructive determination of the echinacoside content in Echinacea roots by ATR-IR and NIR spectroscopy. Planta Med. 68, 926-929. 

Echinacea species (coneflower, black Sampson hedgehog, Indian head, snakeroot, red sunflower, scurvy root) have become increasingly popular, particularly for the prophylaxis and treatment and prevention of cold and flu symptoms. However, the claimed efficacy of Echinacea in the common cold has not been confirmed in a randomized, double-blind, placebo-controlled trial (20) or a systematic review (21). Echinacea is claimed to have antiseptic and antiviral properties and is under investigation for its immunostimulant action. The active ingredients are glycosides (echinacoside), polysaccharides, alkamides, and flavonoids. 

Echinacea has been used topically for wound-healing. The exact mechanism is unknown but is likely caused by antihyaluronidase activity of echinacoside. A study investigating this activity found that E. pallida, which is known to contain echinacoside, had more anti-inflammatory and woundhealing activity in rats after topical application. The effects were much greater with E. pallida compared with E. purpurea and control (22). 

Two in vitro studies have demonstrated anti-inflammatory activity by various Echinacea preparations. Speroni et al. showed anti-inflammatory activity attributed to echinacosides in E. pallida in rats. Another in vitro study used E. purpurea in mice that had induced paw edema. Only the higher dose used in the study downregulated COX-2 expression. The authors suggested that the anti-inflammatory properties of Echinacea are related to this inhibition (24). 

Analysis of dilutions of extract of E. angustifolia and E. purpurea showed medium to high levels of inhibition of cytochrome P450 3A4 in vitro. Testing of chicoric acid and echinacoside alone showed low to very low inhibition. 

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