An efficient biotransformation of progesterone into 11α-hydroxyprogesterone by Rhizopus microsporus var. oligosporus.

Rhizopus microsporus var. oligosporus is a fungus that belongs to the Mucoraceae family that is used for the preparation of some soy-fermented foods. Microbial biotransformation of progesterone by R. microsporus var. oligosporus afforded some monohydroxylated and dihydroxylated metabolites. The main product was purified using chromatographic methods and identified as 11α-hydroxyprogesterone on the basis of its spectroscopic features. Time course studies by high-performance thin-layer chromatography demonstrated that this fungi efficiently hydroxylated progesterone at the 11α-position for 3 days with a yield of 76.48%, but beyond this time, the microorganism transformed 11α-hydroxyprogesterone into dihydroxylated metabolites. 11α-Hydroxyprogesterone is widely used as a precursor in the synthesis of hydrocortisone and other steroidal anti-inflammatory agents.