Microbial transformation of 4-ene-3-one steroids by Mucor racemosus

Abstract:

A steroid-converting fungus isolated from soil samples, was identified as Mucor racemosus according to its morphological characters. The application of M. racemosus for biotransformation of 4-ene-3-one steroids had been investigated to obtain hydroxylated derivatives of 4-ene-3-one steroids. The substrates were incubated with M. racemosus in rotary shaker (220 rpm) culture for a period of four days at 27℃. All of the fermentation media were exhaustively extracted with ethyl acetate and filtered to separate the both from the mycelium. The transformation products were separated on silica gel column chromatography. Each microbial metabolite was characterized by spectroscopic methods such as IR, MS and NMR. Fermentation of progesterone yielded 14α-hydroxypregn-4-en-3,20-dione and 7α,14α-dihydroxypregn-4-en-3,20-dione. Incubation of androstenedione resulted in three transformation products: 14,17-dihydroxyandrost-4-en-3-one, 14α,17β-dihydroxyandrost-4-en-3-one and 6α,17β-dihydroxyandrost-4-en-3-one. This fungus was found to biotransformation steroids. The results showed that the fermentation of 4-ene-3-one steroids with M. racemosus yielded mainly 14α-hydroxy steroids.

Key words:Microbial transformation; Mucor racemosus; 14α-Hydroxylation; steroids