Rearrangement and oxidation of beta-amyrin promoted by growing cells of Lecanicillium muscarinium.

Microbial transformation of beta-amyrin by growing cells of the fungus Lecanicillium muscarinium (former Cephalosporium aphidicola) was successfully accomplished after 15 days of incubation with orbital shaking at 120 rpm. Two products purified by column chromatography were identified by 1H and 13C mono- and bi-dimensional nuclear magnetic resonance as 3beta-hydroxy-olean-12-en-11-one and 11alpha,12alpha-oxidotaraxerol; these later formed new compounds formed by an interesting oxidative rearrangement of the starting material, probably via an initial hydroxylation at C-11.