Three Novel Dietary Phenolic Compounds from Pickled Raphanus Sativus L. Inhibit Lipid Accumulation in Obese Mice by Modulating the Gut Microbiota Composition

SCOPE: Although pickled radish is widely consumed worldwide, few studies have investigated the nutritional benefits of bioactive compounds extracted from pickled radish. In this study, the authors investigate the relationship among dietary phenolic compounds, lipid accumulation, and gut microbiota. METHOD AND RESULTS: Three phenolic compounds 2,6-dihydroxyacetophenone (DHAP), 4-hydroxyphenethyl alcohol (4-HPEA), and 4-hydroxybenzaldehyde (HBA) are extracted from pickled radish. LO2 cells treated with free fatty acid are first used to explore the impact of the above three compounds at different doses on reducing lipid levels. The effects of the three compounds on obesity and the gut microbiota are further investigated in high-fat diet (HFD)-induced KM mice. Results show that three compounds inhibited the lipid accumulation in LO2 cells. The results of animal experiments reveal that three compounds prevented body weight gain and significantly decreased serum lipid levels. Treatment with DHAP, HPEA, and HBA reversed gut microbiome dysbiosis in HFD-induced mice. The three phenolic compounds increase Odoribacter, and decrease Helicobacter and Mucispirillum. Notably, DHAP and HBA reduce the HFD-induced increase in the Firmicutes/Bacteroidetes ratio. CONCLUSION: These data suggest that phenolic compounds extracted from pickled radish possess excellent lipid-lowering capacity, providing a theoretical basis for further analysis of the nutritional value of pickled radish.