Abstract: Objective: To examine whether sweet potato resistant starch (SPRS) lowers blood lipid levels and benefits the liver of hyperlipidemic rats. Methods: Forty SD rats (half male and half female) were randomly divided into 4 groups including normal control group, hyperlipidemia model group, SPRS low-dose group and SPRS high-dose group. Rats fed a normal diet were served as the normal control group and rats fed a high-fat diet as the hyperlipidemia model group. The rats in SPRS groups were administered with SPRS by gavage at the daily doses of respectively 10 g/(kg·d) and 20 g/(kg·d) and also fed a high-fat diet. After 45 days of administration, serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and morphological changes in the liver of all the rats were examined. Results: SPRS could significantly reduce the contents of TC, TG and LDL-C, and increase the content of HDL-C in rat serum. Meanwhile, the liver degeneration and damage of the SPRS groups were markedly attenuated compared with the hyperlipidemia model group. Conclusion: SPRS has an excellent regulatory effect on blood lipid level and enhances the recovery of liver damage in rats with hyperlipidemia.

Key words: sweet-potato resistant starch, hyperlipemia, blood lipid lowering effect, hepatic function