INDUCTION BY MANGANESE, ETHANOL, PHENOBARBITAL, AND HERBICIDES OF MICROSOMAL CYTOCHROME-P-450 IN HIGHER-PLANT TISSUES

Cytochrome P-450 content and, to a lesser extent the activity of tr-cinnamic acid 4-hydroxylase, are induced in ageing Jerusalem artichoke (Helianthus tuberosus L.) tuber cells by manganese ions, ethanol, phenobarbital, and herbicides. Manganese, ethanol, and phenobarbital induced cytochrome P-450 and also modified the time-course of its appearance. In contrast the herbicides tested stimulated the cytochrome P-450 content without modifying its time-course. The extent of induction was enhanced when the aging medium was supplemented with iron. © 1979.