Abstract:In this study, the effects of barley bran extract fermented by Lactiplantibacillus plantarum dy-1 (Lp. plantarum dy-1) (FBBE) on lipid deposition and oxidative stress were investigated through a HepG2 high-lipid cell model. The results showed that, the protein content of barley bran did not change significantly after the fermentation with Lp. plantarum dy-1, but the protein with a relatively high Mw (around 52 ku) in barley bran was basically completely hydrolyzed, with the protein of 20~35 ku increasing significantly. The total sugar content was reduced by about 28% and the total phenolic content increased by about 42%. The FBBE treatment at 50 μg/mL decreased the TG content by 20.30%, whilst the polyphenols in the FBBE (FBBE-PP) at 5, 10 or 15 μg/mL decreased the TG levels by 16.97%, 27.41% and 34.92%, respectively, while reducing significantly the number of lipid droplets in the cells, indicating that polyphenol constituents were the effective components to alleviate lipid deposition in cells. After the FBBE-PP treatment at 10 μg/mL, the intracellular ROS content decreased by 23.45% and the SOD activity increased by 40.80%, compared with the model group. The FBBEPP could up-regulate the expressions of ppar-α and cpt-1α, down-regulate the expressions of scd-1 and acc-1 to alleviate cell lipid deposition, while up-regulating the expressions of nrf-2, ho-1, sod1 and cat to enhance the antioxidative stress ability of cells. In conclusion, the fermentation with Lp. plantarum dy-1 could improve the lipid-lowering and antioxidant activities of barley bran, and its polyphenol components could significantly alleviate high-fat induced lipid deposition and oxidative stress in cells.
