Differential effects of powdered whole soy milk and its hydrolysate on antiobesity and antihyperlipidemic response to high-fat treatment in C57BL/6N mice.

This study was performed to investigate the beneficial effects of powdered whole soy milk and its hydrolysate, compared to the processed soy milk and its hydrolysate, on the alteration of lipid metabolism and their possible effects on antiobesity in C57BL/6N mice fed a high-fat and -cholesterol diet. The mice were divided into a control group (20% casein) and four test groups for 5 weeks: soy milk (SM, 20% soy milk protein), soy milk hydrolysate (SMH, 20% hydrolyzed soy milk protein), whole soy milk (WSM, 20% whole soy milk protein), and whole soy milk hydrolysate (WSMH, 20% whole soy milk hydrolysate protein). The body weight and adipose tissue weights were significantly lowered in SMH, WSM, and WSMH groups compared to the control group despite providing an isoenergetic diet. Plasma lipid concentrations and hepatic fatty acid synthase (FAS) and glucose-6-phosphate dehydrogenase (G6PD) activities were significantly lowered in all soy milk groups; however, the hepatic lipid contents and malic enzyme (ME) activity were only significantly lowered in the WSM and WSMH groups, compared to the control group. Data suggest that powdered WSM or WSMH appears to be more beneficial than SM or SMH in overall antiobesity and antihyperlipidemic properties following in the order WSMH/WSM, SMH, SM, and casein.