Echinacea purpurea aerial part

Echinacea has been generally well tolerated in clinical trials, with most trials reporting similar incidences of adverse reactions for Echinacea and placebo (Huntley et al. 2005). One trial of fresh juice of Echinacea purpurea aerial parts in children showed a significantly higher incidence of rashes in children taking the Echinacea preparation than in children taking placebo (Taylor et al. 2003). 

Upton, R., and A. Graff. 2007. Echinacea purpurea aerial parts Standards of analysis, quality control, and therapeutics. American Herbal Pharmacopoeia. Scotts Valley, CA. 

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. 

Preparations from Echinacea purpurea aerial parts... 

Echinacea is sold as a dietary supplement in the United States and as a natural health product in Canada. However, Health Canada does support the use of Echinacea in food products thus functional foods could be developed for the Canadian market. In the United States and Canada, there are no restrictions on the species/varieties used in products. In Germany and many European countries, Echinacea products are sold as drugs in pharmacies (Bauer, 2000). In addition, not all products are approved for use in all countries. For example, E. purpurea aerial parts and E. pallida roots are approved in Germany whereas E. angustifolia and E. purpurea roots are not (Blumenthal, 1998). 

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). 

In addition to oil-stability evaluations, AA retention was evaluated in orange juice treated with E. purpurea and E. angustifolia extracts and stored at room temperature. Our initial studies at North Dakota State University showed that the addition of ground Echinacea plant tissue was ineffective at preventing AA loss. For example, only 8% of the AA remained after 48 h in the orange juice treated with dried aerial parts. A 30% loss of AA after 48 h was found in the control juice. In contrast, 91 and 94% of AA was retained in the orange juice treated with ethanol extracts of the aerial parts and roots, respectively. In a subsequent study,... 

Pharmacology In vitro studies have shown that echinacea has cytokine activation (increased interleukins and tumor necrosis factor) and anti-inflammatory properties. At the clinical level, two reasonably well-controlled studies have documented a reduction in duration of cold S3fmptoms with the use of freshly pressed juice of the aerial parts of E purpurea. 

The freshly pressed juice of the aerial parts of Echinacea purpurea have been shown to significantly reduce the symptoms of the common cold and the time of recovery. The answer is (A). 

In vitro studies on the effect of Echinacea purpurea on GYP enzymes have given mixed results. Results from one study on the effects of a preparation of the aerial parts of Echinacea purpurea on CYP3A4 differed according to the model substrate used one substrate (7-benzyloxy-4-trifluoromethyl-coumarin) indicated induction, while the other (resorufin benzyl ether) indicated inhibition (Yale and Gulrich 2005). Another study showed significant inhibition by a "commercial grade extract" (no other description provided) of Echinacea angustifolia root (Budzinski et al. 2000). 

A preparation of the aerial parts of Echinacea purpurea moderately inhibited CYP2C9 but did not influence CYP2D6 activity (Yale and Gulrich 2005). 

When dealing with the pharmaceutical quality and pharmacological activity of Echinacea preparations, it is important to distinguish between the different species, parts of the plants, and the various extraction modes. Since aerial parts and roots of Echinacea purpurea, and the roots of Echinacea angustifolia and Echinacea pallida are the most important raw materials of Echinacea phytopharmaceuticals, the constituents and immunological effects of these parts shall be especially reviewed. 

Roots of Echinacea purpurea contain up to 0.2% essential oil [4, 14,15, 21, 67, 69, 74]. According to Becker [75] and Martin [76] it is composed of 2.1% caryophyl-lene, 0.6% humulene and 1.3% caryophyllene epoxide. Heinzer et al. [14] have analyzed the essential oil by gas chromatography-mass spectrometry (GC-MS) and found compounds of the type dodeca-2,4- dien-l-yl-isovalerate, as well as palmitic and linolenic acid, vanillin, p-hydroxycinnamic acid methyl ester and germacrene D, which had already been reported by Bohlmann and Hoffmann [27] for the aerial parts of the plant. Nevertheless, . purpurea roots are not a typical essential oil drug, and therefore analysis of the essential oil has not been used often for standardization purposes of phytopreparations. However, gas chromatography of the essential oil can be used for the discrimination of the species (see Fig. 1) [14]. 

The aerial parts of Echinacea purpurea contain alkamides of the same 2,4-diene type as found in the roots. Main constituents are dodeca-2 ,4 ,8Z,10 /Z-tetra-enoic acid isobutylamides [27, 82]. As minor constituents the isobutylamides of... 

HPLC analysis with photodiode array detection is the best method for analysis of alkamides, because the different types can be identified via their UV-spectra. However, it is difficult to distinguish the aerial parts of the different Echinacea species, because they show no qualitative difference in the alkamide pattern (see Fig. 15) [30, 82]. HPLC is also useful for the determination of the contents of alkamides and was applied successfully for the analysis of fresh plant tinctures [99]. It could be shown that the yield in the aerial parts is 0.001-0.03% [30]. Small amounts of alkamides can also be found in the expressed sap of . purpurea [100]. It could be shown that the content varies considerably between the different products on the market and even in between the batches of one product (Fig. 16) [100]. One reason may be the seasonal variation of the alkamide content, which is low at the beginning of the vegetation period and becomes high only in the middle of August (data of 1996, see Fig. 17) [101]. Another reason may be the different yields of alkamides in the various parts of the plant. Alkamides are especially accumulated in the flower heads in particular in the tubulous flowers and achenes (Fig. 18) [82, 101, 102]. Therefore the date and mode of harvest play an important role and standardization is urgently needed. 

The main caffeic acid derivative in the aerial parts of Echinacea purpurea is cichor-ic acid (2R,3R-0-dicaffeoyl-tartaric acid). It was first isolated from the leaves of . purpurea by Becker and Hsieh [83]. Hsieh [106] reported no data on the optical activity of cichoric acid. The cichoric acid isolated later from . purpurea by Remiger [84] and by Soicke et al. [107] had an optical rotation [a] of ca. -370 . In contrast, the cichoric acid first isolated by Scarpati and Oriente [108] from Cichorium intybus displayed a rotation of +383.5 . Cichoric acid from lettuce Lac-tuca sativa) [109] and from endives (Cichorium endivia) [110] was also dextrorotatory. Synthetic studies by Scarpati and Oriente [108] showed that cichoric acid from Cichorium intybus contains a residue of (2S,3S)-(-)-tartaric acid. Conversely, that in... 

HPLC separation of the lipophilic fractions of the aerial parts of Echinacea purpurea, E. pallida and E. angustifolia. From Bauer et al. [82]. 

Seasonal variation of the content of cichoric acid and dodeca-2E,4E,8Z,10E,Z-tetraenoic acid-isobutylamide in aerial parts of Echinacea purpurea [101]. 

Giger et al. [51] investigated the fructan content of Echinacea purpurea and found that the aerial parts contained ten times less than the roots and that homeopathic tinctures contained fructans with polymerization grades up to 15. It has been suggested to standardize Echinacea purpurea fresh plant preparations on the content of P-l,2-fructofuranosides [128]. The method is based on enzymatic hydrolysis of the fructans by invertase and subsequent determination of fructose by HPLC. Since 3-l,2-fructofuranosides are easily degraded enzymatically during the manu-... 

Immunomodulatory active polysaccharides have been isolated from the aerial parts of . purpurea [118, 123]. Their pharmacological activity is well documented and will be reviewed in the chapters by Wagner et al. and Emmendorffer et al. in this volume [150, 151]. Lectins from Echinacea purpurea have been shown to possess agglutinative properties and it is argued that they may also have adaptogenic effects [86]. 

Schulthess BH, Giger ER, Baumann TW (1991) Echinacea anatomy, phytochemical pattern, and germination of the achene. Planta Med 57 384-388 Bauer R, Remiger P, Wray V, Wagner H (1988) A germacrene alcohol from fresh aerial parts of Echinacea purpurea, Planta Med 54 478-479... 

Two recent reviews have assessed the efficacy of echinacea for this primary indication. A review by the Cochrane Collaboration involved 16 randomized trials with 22 comparisons. Trials were included if they involved monopreparations of echinacea for cold treatment or prevention. Prevention trials involving rhinovirus inoculation versus natural cold development were excluded. Overall, the review concluded that there was some evidence of efficacy for the aerial (above ground) parts of E purpurea plants in the early treatment of colds but that efficacy for prevention and for other species of echinacea was not clearly shown. Among the placebo-controlled comparisons for cold treatment, echinacea was superior in nine trials, showed a positive trend in one trial, and was insignificant in six trials. 

---