Microbial transformation of dehydroepiandrosterone (DHEA) by some fungi

Abstract

In this work, biotransformations of dehydroepiandrosterone (DHEA) 1 by Ulocladium chartarum MRC 72584, Cladosporium sphaerospermum MRC 70266 and Cladosporium cladosporioides MRC 70282 have been reported. U. chartarum MRC 72584 mainly hydroxylated 1 at C-7α and C-7β, accompanied by a minor hydroxylation at C-4β, a minor epoxidation from the β-face and a minor oxidation at C-7 subsequent to its hydroxylations. 3β,7β-Dihydroxy-5β,6β-epoxyandrostan-17-one 6, 3β,4β,7α-trihydroxyandrost-5-en-17-one 7 and 3β,4β,7β-trihydroxyandrost-5-en-17-one 8 from this incubation were identified as new metabolites. C. sphaerospermum MRC 70266 converted some of 1 into a 3-keto-4-ene steroid and then hydroxylated at C-6α, C-6β and C-7α, accompanied a minor 5α-reduction and a minor oxidation at C-6 following its hydroxylations. C. sphaerospermum MRC 70266 also hydroxylated some of 1 at C-7α and C-7β. C. cladosporioides MRC 70282 converted almost half of 1 into a 3-keto-4-ene steroid and then hydroxylated at C-6α and C-6β. C. cladosporioides MRC 70282 also reduced some of 1 at C-17.

Keywords:

• Ulocladium chartarum
• Cladosporium sphaerospermum
• Cladosporium cladosporioides
• dehydroepiandrosterone
• biotransformation

Acknowledgements

We are grateful to Yavuz Derin and Fatih Sonmez for running the ¹H and ¹³C NMR spectra. This work is dedicated to the memory of Professor James Ralph Hanson and Sir John Warcup Cornforth who taught us how to work on natural products.

Disclosure statement

The authors report no decleration of interest. The authors alone are responsible for the content and writing of the paper.