Microbial Transformation of Galangin Derivatives and Cytotoxicity Evaluation of Their Metabolites

Fubo Han,Ik-Soo Lee,Yina Xiao

doi:10.3390/catal11091020

Abstract

Galangin (1), 3-O-methylgalangin (2), and galangin flavanone (3), the major bioactive flavonoids isolated from Alpinia officinarum, were biotransformed into one novel and four known metabolites (4–8) by application of the fungal strains Mucor hiemalis and Absidia coerulea as biocatalysts. Their structures were characterized by extensive spectroscopic analyses including one- and two-dimensional nuclear magnetic resonance spectroscopy and mass spectrometry. Compounds 1–7 were evaluated for their cytotoxic activities against cancer cell lines using the MTT assay. The new compound 3-O-methylgalangin-7-O-β-D-glucopyranoside (6) exhibited the most potent cytotoxic activity against MCF-7, A375P, B16F10, B16F1, and A549 cancer cell lines with the IC50 values at 3.55–6.23 μM.

Highlights

The rhizome of Alpinia officinarum Hance (AOH), commonly known as lesser galangal, is a well-known traditional Chinese medicine that has been widely used as an antiemetic, stomachic, and analgesic in Asia for thousands of years [1,2]
Results and Discussion methods and identified by comparison of their NMR data with those reported in the litGalangin (1) and its derivatives 3-O-methylgalangin (2) and galangin flavanone erature and retention times with standard compounds
Of the 14 microorganisms were isolated from Alpinia officinarum by column chromatographic methscreened, Mucor hiemalis Korean Collection for Type Cultures (KCTC) 26779 and Absidia coerulea KCTC 6936 were selected for ods and identified by comparison of their NMR data with those reported in the literature preparative-scale fermentation studies since they were found to be capable of metaboand retention times with standard compounds

Summary

Introduction

The rhizome of Alpinia officinarum Hance (AOH), commonly known as lesser galangal, is a well-known traditional Chinese medicine that has been widely used as an antiemetic, stomachic, and analgesic in Asia for thousands of years [1,2]. It has been reported to produce anticancer effects against a wide variety of human cancers including melanoma, liver, colon, breast, and lung cancers [3]. Flavonoids naturally exhibit low toxicity in biological systems, which makes them an alternative therapy for the treatment of cancers in comparison with traditional anticancer drugs [5]. Flavonoids of AOH have been reported to exhibit various pharmacological effects such as analgesic, antiemetic, antioxidant, hypoglycemic, and anticancer activities [6] consistent with the functions and indications of AOH, indicating that flavonoids are the basic medicinal components of AOH

Methods

Results

Conclusion