Showing papers on "Withania somnifera published in 1984"

Distribution of the chemotypes ofWithania somnifera in some areas of Israel: Feeding studies withSpodoptera littoralis larvae and chemical examination of withanolide content

Abstract: The geographical distribution of the chemotypes ofWithania somnifera Dun. (Solanaceae) in Israel was re-investigated. In the distribution area of chemotype II (major steroidal constituent, withanolide D), plants of chemotype III (major steroidal constituent, withanolide E) were also found. The antifeedant properties forSpodoptera littoralis larvae of leaves ofW. somnifera populations belonging to chemotype III are due to the presence of withanolide E and may be used, as a supplement to chemical analysis, to differentiate between chemotype III and other chemotypes ofW. somnifera.

Withanolides of withania somnifera l. dunal growing wild in egypt

Abstract: Three Withanolides (Substances A,B, and C) were isolated from the alcoholic extract of the Egyptian Withania somnifera wild plants. Substance A and substance C were identified by IR, NMR and Mass spectral data. Substance A appears to be a configurational isomer of Withanolide E and substance C is 4-hydroxy derivative of substance A. Substance A is identified as 14,17,20-trihydroxy-5B,6B-epoxy-1-oxo-Witha-2,24-dienolide (I) and substance C as 4,14,17,20-tetrahydroxy-5B, 6B-epoxy-1-oxo-witha-2,24-dienolide(II). This is the first report of isolation and characterization of substance C from Withania somnifera or the genus Withania. Substance B would be the subject of a further report.