Shannon E. Binns

Phytochemical variation within populations of Echinacea angustifolia (Asteraceae)

Quantitative evaluation of phytochemical diversity in Echinacea angustifolia DC. populations from different natural geographic areas supports the existence of distinct natural chemotypes within the species. Consumers, growers and manufacturers of phytomedicines are interested in chemotype identification for prediction of phytochemical content in cultivar development. Six month old E. angustifolia roots, grown from nine different wild seed sources in a controlled environment, were extracted into 70% ethanol and 28 reported phytochemicals were measured by HPLC separation. Two-way ANOVA between the nine populations revealed quantitative differences (p<0.05) in the caffeic acid derivatives 2,3-O-dicaffeoyl tartaric acid (cichoric acid), 2-O-caffeoyl tartaric acid (caftaric acid), 1,3-dicaffeoyl-quinic acid (cynarin), echinacoside and ten reported alkamides. Canonical discriminant analysis determined the phytochemical variables which contributed the most towards chemotype distinction for five of the nine populations: undeca-2E,4Z-diene-8,10-diynoic acid-2-methylbutylamide*, dodeca-2E,4E-dienoic acid isobutylamide*, dodeca-2E-ene-8,10-diynoic acid isobutylamide**, hexadeca-2E,9Z-diene-12,14-diynoic acid isobutylamide*, cichoric acid**, caftaric acid*, and echinacoside** (*p<0.0001, **p<0.05). Five of those compounds were also significantly associated with latitudinal variation by regression analyses (p<0.05).

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

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. Mantels test showed that there was a weak correlation but a strong association of values of the phytochemical variables and the DNA polymorphism data.

Antifungal and Anti-inflammatory Activity of the Genus Echinacea

The antifungal activity and 5-lipoxygenase-inhibiting activity of extracts of five wild and three commercially used taxa of the genus Echinacea were investigated. The near-UV mediated antifungal bioassays included clinically isolated Cryptococcus neoformans, two Candida albicans isolates (D10 and CN1A) with amphotericin B resistance, as well as established and emerging filamentous fungal pathogens (Trichophyton tonsurans, T. mentagrophytes, Microsporum gypseum and Pseudallescheria boydii). Root extracts of the eight Echinacea taxa showed antifungal activity against most of the pathogenic fungi. The inhibition of the 5-lipoxygenase (5-LOX) enzyme of the arachadonic acid pathway was determined by HPLC detection of a direct metabolic product (LTB 4) of 5-LOX derived from stimulated rat basophilic cells. Root extracts of the three commercial species of Echinacea (E. purpurea, E. pallida var. angustifolia, E. pallida var. pallida) inhibited the 5-LOX enzyme. E. pallida var. angustifolia was the most potent of the three. The results show that Echinacea spp: have significant antifungal and antiinflammatory activity.

Methyl jasmonate increases reported alkamides and ketoalkene/ynes in Echinacea pallida (Asteraceae).

Methyl jasmonate (MJ), a naturally-occurring plant cellular signal molecule, was found to induce production of lipophilic secondary metabolites in Echinacea pallida seedlings. Seedling aerial parts were sprayed with 100 ppm MJ, and roots were harvested and extracted 24 h later. Lipophilic root extracts, separated by HPLC, revealed significant increases (P< 0.05) in six alkamides or related ketoalkene/ynes produced by 34 day-old plants and in seven compounds produced by 58 day-old plants.

Typification of Echinacea purpurea (L.) Moench (Heliantheae: Asteraceae) and its implications for the correct naming of two Echinacea taxa

A thorough investigation of relevant nomenclatural types and descriptions reveals that the name Echinacea purpurea (L.) Moench, which was lectotypified by McGregor in 1968, has been consistently misapplied since 1903 to ataxon distinctly different from that of its modern lectotype and of the original Linnaean concept. Linnaeuss original concept of Rudbeckia purpurea, maintained by Candolle as Echinacea purpurea when he segregated E. serotina (Nutt.) DC., is the species now known as E. laevigata (C. L. Boynton & Beadle) S. F. Blake. Technically, therefore, the correct name for the species currently called E. laevigata is E. purpurea (L.) Moench, and the correct name for the species currently called E. purpurea is E. serotina (Nutt.) DC., for which a lectotype is designated. Conservation of the name E. purpurea in the sense of its current application, which also preserves the usage ofE. laevigata, is proposed in a separate article (see Binns & al., p. 1199, this issue).