Enzymatic Synthesis and Evaluation of Eight Methylated Quercetin Products: In Vitro Chemical Properties and Adipogenesis Regulation

• DOI: 10.1021/acs.jafc.5c00426
• Publication Date: 2025-05-21T03:06:05Z
• Authors: Beijun Ang; Tian Yang; Hongtao Jiang; Yong Cheng; Yang Chen; Xuejiao Qie; Liduan Yin; Tong Wang; Qiuming Chen; Zhaojun Wang; Maomao Zeng; Benu Adhikari; Zhiyong He; Jie Chen

The methoxylated modification of flavonoids has been reported to enhance stability and permeability; however, its effect on the improvement activity is not clear. In this study, Citrus depressa flavonoid O-methyltransferase 5 Sorghum vulgare 7-O-methyltransferase were recombinantly expressed successfully converted quercetin (QUE) into eight products, which isolated identified with a purity exceeding 95%. All products except rhamnetin (RHA) showed improved stability, while only 5,7,3',4'-EMQ, 7,3',4'-TMQ, 3,7,3',4'-EMQ had higher uptake ratios. Compared QUE, 5,7,3',4'-EMQ RHA significantly reduced intracellular triglyceride level, 3,5,7,3',4'-PMQ, 3,3',4'-TMQ increased it. also downregulated both mRNA protein levels peroxisome proliferator-activated receptor γ, 3,5,7,3',4'-PMQ upregulated PPARγ at transcriptional level about ten times than that QUE. structure-activity relationship analysis highlighted importance C3-OH retention dual methoxylation A-ring. summary, study efficiently produced structurally well-defined QUE via biotransformation, established an in vitro initial for regulating adipogenesis, provided potential structure regulation, central target lipid metabolism.