Abstract: Rice vinegar residue, a by-product of rice vinegar making, is wasted in enormous quantity, which has been believed to have potential effects in the regulation of lipid metabolism. This study aimed to investigate the effects of rice vinegar residue on lipid metabolism in hypercholesterolemic hamsters. Rice vinegar residue at doses of 200 and 500 mg/(kg mb·d) and rice vinegar at 200 mg/(kg mb·d) were separately given by gavage to hamsters for 30 days. Both rice vinegar residue and rice vinegar significantly lowered the concentration of low-density lipoprotein cholesterol in plasma (P < 0.05), reduced the average size of adipocytes in white adipose tissues, and increased the fecal concentrations of triglycerides, total cholesterol and bile acids (P < 0.05). Moreover, vinegar residue disrupted solubilization of intestinal cholesterol into micelles (P < 0.05), as well as inhibited its binding to cholate (P < 0.05). On the other hand, vinegar residue had no inhibitory effect on lipase activity. Eventually, we conclude that rice vinegar residue has potential beneficial effects on lipid metabolism and obesity by preventing the absorption of cholesterol in the intestine and promoting the excretion of fecal lipids and cholesterol synthesis in the liver, which may be related to the combination between vinegar residue and cholate.

Key words: rice vinegar residue, hypercholesterolemia, adipocyte size, fecal lipids, lipid absorption