Bioconversion of Dehydroepiandrosterone to 3β，7α，15α-Trihydroxy-5-Androsten-17-One by Colletotrichum lini ST-1 Resting Cells

Abstract:

The bioconversion of dehydroepiandrosterone（DHEA） to 3β，7α，15α-trihydroxy-5- androsten-17-one by Colletotrichum lini ST-1 resting cells was investigated. The optimal transformation parameters in flasks were cell concentration 12 g/L，pH 6.5，liquid volume 30 mL/250 mL，rotational speed 220 r/min and temperature 30 ℃，which resulted in a molar product yield of 38.5% for 7α，15α-diOH-DHEA that was 20.1% higher than that from growing cells. Based on these conditions，two-batch bioconversion for 78 h with resting cells at a total substrate concentration of 18 g/L resulted in a concentration of 12.1 g/L and a molar product yield of 60.5% for 7α，15α- diOH-DHEA.