Abstract: Objective: To explore the hypolipidemic effect of Auricularia auricular polysaccharides in vitro and in
vivo. Methods: Under simulated human gastric and intestinal pH conditions, the cholate binding capacity and in vitro
hypolipidemic effect of Auricularia auricular polysaccharides extracted with different solvents and their alcohol-precipitated
fractions. To evaluate the hypolipidemic effect of alkali-soluble polysaccharides from Auricularia auricular, the changes in
body weight, serum total cholesterol (TC), total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density
total cholesterol (HDL-C) and the activity of lecithin cholesterol acyltransferase (LCAT), which is the key enzyme involved
in HDL-C metabolism, and hepatic lipase (HL) and lipoprotein lipase (LPL) activities in hyperlipidemic rat models induced
by high-fat feeding were detected before and after oral administration of the polysaccharides. Results: Among three different
solvent soluble polysaccharides from Auricularia auricular, the alkali-soluble polysaccharides had the strongest cholate
binding capacity, which was most ascribed to the 70% ethanol-precipitated fraction. In addition, this polysaccharide fraction
could significantly alleviate body weight gain, slow down the increase in serum TC, TG and LDL-C, increase LDL-C
significantly, and block the decrease in LCAT, HL and LPL activities. Conclusion: The 70% ethanol-precipitated fraction of
alkali-soluble polysaccharides from Auricularia auricular had a significant hypolipidemic effect in experimentally induced
hyperlipidemic rats.

Key words: Auricularia auricular polysaccharides, cholate, hypolipidemic, lecithin cholesterol acyltransferase (LCAT)