Microbial oxidation of dehydroepiandrosterone and related compounds

The oxidation of dehydroepiandrosterone (DHEA), 4-androstene-3, 17-dione, and estrone with Streptomyces roseochromogenes NRRL B-1233 was studied. The oxidation products were isolated and identified as as 16alpha-hydroxy-DHEA, 16alpha-hydroxy-4-androstene-3,17-dione and 16alpha-hydroxyestrone. The yields of these three products were 85%, 41% and 18%, respectively. This indicates the substrate stereospecificity of 16alpha-hydroxylase of the organism. An interrelationship between cell growth and the formation of 16alpha-hydroxylated steroid was observed in any case. For formation of 16alpha-hydroxy-DHEA, 16alpha-hydroxylase showed good activity at DHEA concentration of 3.47 x 10(-4)M. In the case of DHEA, 16alpha-hydroxy-4-androstene-3,17-dione and 5-androstene-3beta, 16alpha, 17beta-triol were obtained after the yield of 16alpha-hydroxy-DHEA reached the maximum yield for about 30 hr. The oxidation pathway of DHEA is discussed.