Microbial transformation of 18beta-glycyrrhetinic acid by Cunninghamella elegans and Fusarium lini, and lipoxygenase inhibitory activity of transformed products.

The microbial transformation of 18beta-glycyrrhetinic acid (1) by Cunninghamella elegans afforded a metabolite, 3beta,7beta-dihydroxy-11-oxo-olean-12-en-30-oic acid (2), while fermentation of 1 with Fusarium lini afforded a metabolite, 3,11-dioxo-olean-12-en-30-oic acid (3). Compound 3 exhibited a potent lipoxygenase (LOX) inhibitory activity. The structures of these metabolites were elucidated on the basis of spectroscopic techniques.