Echinacea purpurea Echinacoside

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. 

The roots of . purpurea do not contain echinacoside, but cichoric acid (2 ,3 -dicaffeoyl tartaric acid) and caftaric acid (monocaffeoyl tartaric acid) as shown in Figures 4 and 11. Cichoric acid was first found as a major constituent in the aerial parts of Echinacea species [82, 83]. Later it was found that it is abundant also in Echinacea purpurea roots and the content has been determined by HPLC to be 0.6-2.1% [84]. Schenk and Franke recently found 0.9% in cultivated material [15]. Cichoric acid undergoes rapid enzymatic degradation (see Echinacea purpurea aerial parts, section on caffeic acid derivatives and phenolic acids) [84]. Therefore, the quality of phytopreparations needs to be thoroughly checked. For analytical methods, see also Echinacea purpurea aerial parts. 

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). 

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). 

Ointment, oral liquid, intravenous and intramuscular ampoules from expressed juice of fresh flowering E. purpurea-, tinctures, extracts, capsules, tablets, and so on of E. angustifolia, E. pallida, and E. purpurea. More than 280 echinacea pharmaceutical products are available in Europe. Echinacea extracts standardized to echinacoside persist in the marketplace, despite the fact that the compound has insignificant biological... 

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