Biotransformation of oleanolic and maslinic acids by Rhizomucor miehei

The biotransformation of oleanolic (1) and maslinic (2) acids with Rhizomucor miehei, are described. The main action of the microorganism on both substrates was hydroxylation at C-30 (3-6). With oleanolic acid (1), R. miehei also hydroxylated at C-7 (4) or at C-1 (5), whereas with maslinic acid (2) the microorganism also produced 11-ene or 11α,12α-epoxy derivatives with an 28,13β-olide group, and an 11-oxoolean-12-ene derivative.