Cholesterol-lowering effect of flaxseed protein hydrolysate peptides
To provide a reference for the deep processing and utilization of flaxseed protein,the flaxseed protein was prepared by alkali-soluble and acid-precipitation method from low-temperature pressed flaxseed cake,and then the flaxseed peptides were prepared by enzymatic hydrolysis.Ultrafiltration membranes were used to isolate flaxseed peptides with the highest cholesterol-lowering activity in vitro,and animal experiments were conducted to explore its cholesterol-lowering effects.The results showed that when the enzymatic hydrolysis time was 4 h,the cholesterol micelle solubility inhibition rate of flaxseed peptide was the highest(47.57%),and the cholesterol micelle solubility inhibition rate of the ultrafiltration fraction with a molecular weight of no more than 3 kDa was the highest(70.96%).Compared with the high-cholesterol diet group,the ultrafiltration fraction(≤3 kDa)could increase the food intake and body weight of mice,reduce the serum total cholesterol(TC),triglyceride(TG)and low-density lipoprotein cholesterol(LDL-C)levels,increase the serum high-density lipoprotein cholesterol(HDL-C)level,reduce liver index and TC and TG levels in the liver,improve the degree of hepatic steatosis,increase fecal total bile acid(TBA)excretion,and reduce the oxidative stress caused by high-cholesterol diet by reducing malondialdehyde(MDA)level and increasing superoxide dismutase(SOD)activity.In conclusion,the ultrafiltration fraction(≤3 kDa)of flaxseed peptides has a certain cholesterol-lowering effect,and is expected to become a new cholesterol-lowering functional component.