Enzymic conversion of reticuline to salutaridine by cell-free systems from Papaver somniferum

A cell-free extract from the opium poppy, Papaver somniferum, was prepared that utilized hydrogen peroxide to convert (+/-)-[3-3H]reticuline to [3H]salutaridine in 80-85% yield based on consumed [3-3H]reticuline. The phenolic-coupling enzyme activity was not detected in the crude homogenate of whole plants. Reticuline conversion to salutaridine was accomplished only after methods were developed to separate both alkaloid and hydrogen peroxide degrading activities from the desired enzyme activity by centrifugal fractionation of carefully prepared stem and root extracts. Purity of the enzymatically produced [3H]salutaridine was established by chromatographic methods and synthetic conversion to [3H]-thebaine.