Biotransformation of (-)-ambrox (1) with cell suspension cultures of Actinidia deliciosa (Kiwifruit) yielded the regio- and stereospecific oxygenated products 3-oxoambrox (2), 3beta-hydroxyambrox (3), 1alpha-hydroxyambrox (4), 3beta,6beta-dihydroxyambrox (5), 1alpha,6beta-dihydroxyambrox (6), and 1alpha,3beta-dihydroxyambrox (7). Metabolites 6 and 7 were found to be new compounds. These metabolites were structurally characterized on the basis of spectroscopic studies. The structure of compound 6 was unambiguously deduced by single-crystal X-ray diffraction techniques. Metabolites 2-7 were evaluated for in vitro inhibitory activity against the thymidine phosphorylase enzyme.

Ashwaghanda, Withania somnifera, is one of the most widely used herbs in Ayurvedic medicine. Leaves and roots are the traditionally used parts of the plant. An RP-HPLC method using a binary acetonitrile-water gradient containing 0.1% acetic acid has been developed for analysis of withaferin A. The method was validated in accordance with ICH guidelines and used for analysis of the withanolide content of the flowers, leaves, and roots of W. somnifera. The withanolide content was highest in the flowers.

No abstract