Abstract: The hypolipidemic effect of chitosan oligosaccharide (COS) and chitosan (CS) was compared in mice fed high-fat diet.Male C57BL/6 mice were randomly assigned to four groups.Control group consumed a normal diet (Control).Model group was fed with a high-fat diet (Model).The COS mice were fed with highfat diet supplement with 5%COS (COS).The CS mice were fed with high-fat diet supplement with 5%CS (CS).The diet intake and weight data were collected weekly,the biochemical indicators of serum and liver,the RT-PCR analysis in liver were determined at the end of the 17 week.The results indicated that supplementation of chitosan oligosaccharide and chitosan can reduce body weight,decrease the levels of serum lipid,liver lipid and increase the hepaticlipase capacity of HF mice.It can alleviate the liver lipid peroxidation,regulate the genes of liver fat metabolism and thus exert the hypolipidemic effect.In addition,chitosan oligosaccharide showed better hypolipidemic effect than chitosan.

Key words: chitosan oligosaccharide, chitosan, high-fat diet, hypolipidemic effect