Lowering serum cholesterol level by feeding a 40% ethanol-eluted fraction from HP-20 resin treated with hot water extract of adzuki beans (Vigna angularis) to rats fed a high-fat cholesterol diet

ObjectiveHot water extract of adzuki beans (Vigna angularis) was subjected to HP-20 resin chromatography. The fraction eluted from the column using 40% ethanol (EtEx.40) was investigated by its effect on serum lipids in rats fed a high-fat cholesterol and/or cholesterol-free high-fat diet.MethodsThe rats were divided into 4 groups. Groups 1 and 2 were fed a high-fat cholesterol diet with or without 3.5% EtEx.40 for 2 wk. Group 3s and 4 were fed a high-fat cholesterol-free diet with or without 3.5% EtEx.40 for 2 wk.ResultsIn the high-fat-cholesterol diet groups, there was no significant difference in food intake in the experimental diet group when compared with the control group. Serum total cholesterol level was significantly decreased in the rats fed the EtEx.40 diet, but there was no difference in fecal excretion of cholesterol and bile acid between the two dietary groups. Conversely, in the high-fat cholesterol-free diet groups, ingestion of EtEx.40 reduced serum triacylglycerol concentration.ConclusionIngestion of EtEx.40 suppressed serum cholesterol level in rats fed the high-fat cholesterol and serum triacylglycerol level in rats fed the high-fat cholesterol-free diet. These mechanisms did not become clear in this experiment.