Taxanes from in vitro Cultures of the Himalayan Yew Taxus wallichiana*

Abstract

Culture conditions have been standardized for initiation of callus cultures of Himalayan yew (Taxus wallichiana) using young stem and needle explants from mature trees. Cultures were established on a modified Murashige and Skoog's medium supplemented with various levels of auxins (2,4-D, NAA) and cytokinin (kinetin). A medium containing 0.25 mg/l kinetin and 5.0 mg/I 2.4-D was optimal for stem callus growth whereas the presence of 0.25 mg/l kinetin along with 3.0 mg/l NAA in the medium supported optimal needle callus growth. Growth of stem callus was faster than needle callus growth. Supplementation of ascorbic acid (30 mg/l) amongst various anti-phenolic agents tested significantly reduced browning of initiated callus. Two taxanes (2-deacetoxytaxinine J and 2′-deacetoxyaustrospicatine) known to occur in stem bark, have also been isolated from undifferentiated tissue of T. wallichiana in equal or higher yields, for the first time.

Key words

Cell culture - Taxus wallichiana - Taxaceae - taxanes