Screening for lactic acid bacteria in traditional fermented Tibetan yak milk and evaluating their probiotic and cholesterol-lowering potentials in rats fed a high-cholesterol diet

The objectives of the present study were to screen cholesterol-lowering lactic acid bacteria from traditional fermented Tibetan yak milk, and to evaluate their potential use as cholesterol-reducing probiotics in rats. A total of 115 isolates were evaluated for their cholesterol-lowering and probiotic profiles by in vitro assays, and a strain with good performance in in vitro test was selected to test its probiotic effects in rats fed a high cholesterol diet. Results showed that the strain of L. plantarum Lp3 had a high cholesterol-reducing rate (73.3%) and survival rate in simulated gastrointestinal fluids. Administration of Lp3 to rats fed a high-cholesterol diet promoted notable declines in serum and liver cholesterol and triglycerides levels, and reduced lipid deposition in the cytoplasm of rat’s liver tissue. These results suggest that the strain of L. plantarum Lp3 could be a potential probiotic to treat hyperlipidemia and to be used in functional food.