Stereoselective 15α-hydroxylation of androsta-1,4-diene-3,17-dione by Gibberella sp. for efficient production of 15α-OH-ADD and 15α-OH-AD.

Androsta-1,4-diene-3,17-dione (ADD) and its hydroxylated derivatives are important steroidal drug intermediates, playing a crucial role in the pharmaceutical industry. This study evaluated the whole-cell biotransformation of ADD by Gibberella sp. CICC 2498 and Absidia sp. CICC 41050. While Absidia sp. showed low efficiency, Gibberella sp. selectively produced two major metabolites, identified as 15α-OH-ADD and 15α-OH-AD via HPLC, MS, and NMR. Through orthogonal design and single-factor experiments, the transformation rate of ADD to 15α-OH-ADD was enhanced from 30.35% to 61.74% under optimal conditions: 1 g L-1 ADD, 12% inoculum, 70 mL medium volume, 120 h incubation, and 1% (v/v) methanol as cosolvent. These results highlight Gibberella sp. as a promising biocatalyst for regio- and stereoselective steroid hydroxylation, providing an efficient microbial strategy for high-value steroidal intermediates in pharmaceutical manufacturing.