Biotransformations of progesterone, pregnenolone,testosterone, dehydroepiandrosterone and epiandrosterone by some aspergillus species

Fungal steroid biotransformations have been widely used throughout the world in order to produce more valuable and functioned compounds due to their remarkable regio- and stereoselectivities. In this study, the biotransformations of progesterone, pregnenolone, testosterone DHEA and epiandrosterone were investigated by Aspergillus sydowii MRC 200653, Aspergillus candidus MRC 200634 and Aspergillus japonicus MRCI-3048. The biotransformations of the steroids by A. sydowii MRC 200653 and A. candidus MRC 200634 resulted in hydroxylated metabolites at different positions of the steroid ring whereas the biotransformations of the steroids by A. japonicus MRC U-3048 yielded no metabolites. Structures of the metabolites were determined by comparison of their melting points, 1H NMR, 13C NMR and IR spectra with those of the starting materials