Characterization of metabolites produced from the biotransformation of 6-shogaol formed by Aspergillus niger

Abstract

6-Shogaol [(4E)-1-(4-Hydroxy-3-methoxyphenyl)-4-decen-3-one] is a pungent and bioactive ingredient of ginger. This study investigated the biotransformation of 6-shogaol by Aspergillus niger. 6-Shogaol was fermented by A. niger, and the resultant metabolites were structurally characterized by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF MS). As a result, 6-shogaol was biotransformed to yield metabolites: M1, M2 (6-paradol), M3, and M4. The major metabolic routes were reduction and hydroxylation; the carbonyl group and double bond of 6-shogaol were reduced to generate M1 and M2, respectively, which were further hydroxylated or reduced to M3 and M4. Among these metabolites, M1 was reported for the first time in this study.