Microbial transformation of resibufogenin by Curvularia lunata AS 3.4381

Abstract

In this paper, the microbial transformation of resibufogenin (1) by Curvularia lunata AS 3.4381 was investigated, and four transformed products were isolated and characterized as 3-epi-resibufogenin (2), 12α-hydroxy-3-epi-resibufogenin (3), 12-oxo-16β-hydroxy-3-epi-resibufogenin (4), and 12β,15-epoxy-3-epi-bufalin-14,15-ene (5). Among them, 4 and 5 are new compounds, and isomerization, hydroxylation, and oxidation reactions in microbial transformation process were observed. Additionally, the cytotoxicities of transformed products (2–5) were also investigated.

Keywords::

• biotransformation
• resibufogenin
• Curvularia lunata
• bufadienolides

Acknowledgments

The authors thank the Funding Project of Competence Development Program for Beijing VET Teachers, the Scientific Research Base Fund for Science and Technology Innovation and Transformation Program, the National Natural Science Foundation of China (21306002), PHR (IHLB), and Beijing Famous Teacher Program for financial support.

Notes

^1. These two authors contributed equally to this work.