Biotransformation of (20S)-20-hydroxymethylpregna-1,4-dien-3-one by four filamentous fungi

Microbial transformation of (20S)-20-hydroxymethylpregna-1,4-dien-3-one (1) by four filamentous fungi, Cunninghamella elegans, Macrophomina phaseolina, Rhizopus stolonifer, and Gibberella fujikuroi, afforded nine new, and two known metabolites 2–12. The structures of these metabolites were characterized through detailed spectroscopic analysis. These metabolites were obtained as a result of biohydroxylation of 1 at C-6β, -7β, -11α, -14α, -15β, -16β, and -17α positions, except metabolite 2 which contain an O-acetyl group at C-22. These fungal strains demonstrated to be efficient biocatalysts for 11α-hydroxylation. Compound 1, and its metabolites were evaluated for the first time for their cytotoxicity against the HeLa cancer cell lines, and some interesting results were obtained.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Microbial transformation of (20S)-20-hydroxymethylpregna-1,4-dien-3-one with four fungi. ► Cunninghamella elegans, Macrophomina phaseolina, Rhizopus stolonifer, and Gibberella fujikuroi were used for biotransformation. ► Nine new and two known metabolites were characterized through detailed spectroscopic analysis. ► Cytotoxic activity of the substrate and metabolites against the HeLa cancer cell lines.