Microbial Glycosylation of Phenanthrene and Bibenzyls by Mucor hiemalis

Abstract

Microbial transformation of denthyrsinin (1), gigantol (2), and batatasin III (3), the major constituents of Dendrobium species (Orchidaceae), was performed using the filamentous fungus Mucor hiemalis KCTC 26779. Three glycosylated metabolites were obtained in the biotransformation of 1-3, and their structures were identified as denthyrsinin-6- O-β-d-glucoside (4), gigantol-5- O-β-d-glucoside (5), and batatasin III-3- O-β-d-glucoside (6) by analyzing 1-dimensional and 2-dimensional-nuclear magnetic resonance spectra, as well as high-resolution electrospray ionization mass spectral data. Among them, metabolite 4 has not been previously reported. Mucor hiemalis was revealed to catalyze enzymatically glucosylation of the hydroxyl group of phenanthrenes and bibenzyls. This research provides an efficient approach for the glycosylation of phenanthrenes and bibenzyls and can expand the library of available phenanthrene and bibenzyl derivatives for further biological evaluations.