The enzymic conversion of squalene, 2(3),22(23)-diepoxide to α-onocerin by a cell-free extract of Ononis spinosa

Abstract

2.3. Preparation of enzyme Seedlings of Ononis spinosa were grown by the University of Liverpool Botanic Gardens. Both roots and leaves of 2 month old seedlings were used as a source of enzyme. About 10 g of tissue were ground with a pestle and mortar under liquid nitrogen. The frozen powder was stirred into 0.1 M potassium phosphate pH 7.2 (30 ml), containing 2% (w/v) soluble polyvinyl pyrollidone, 0.05% (w/v) cysteine, ascorbate (0.05 M) and sucrose (0.2 M). The homogenate was strained throu.& gauze and the filtrate centrifuged at 20,000 g for 20 min. The pellet was discarded. All manipulations were carried out at o-4O.