Biotransformation of epiandrosterone by Aspergillus glaucus

In the present work, epiandrosterone (15) was incubated with Aspergillus glaucus MRC 200914 in order to see how this fungus metabolises the substrate. One liter of the medium was prepared and evenly disrubuted into 10 erlenmeyer flasks of 250 mL. The medium in flasks was then sterilized by an autoclave. These flasks were inoculated by A. glaucus. The flasks were incubated for 3 days at 25 oC on a shaker and the substrate in DMF was then added aseptically into them. All flasks were further incubated for 5 days. After 5 days, the mycellium was separated from the broth by filtration under the vacuum. The mycellium was rinsed with ethyl acetate and the broth was then extracted with ethyl acetate. The extracts were dried over sodium sulfate anhydrous and evaporated in vacuo to give a brown gum which was then chromatographed on silica gel 60. 11α-hydroxy-5α-androstan-3,17-dione (16), 3β,11α-dihydroxy-5α-androstan-17-one (17) and 3β,7α-dihydroxy-5α-androstan-17- one (24) were obtained from the chromatography work. The structures of these compounds were determined by comparing melting points, NMR and IR spectra of the substrate with those of steroids.