Dietary Soybean Peptides Containing a Low-Molecular Fraction Can Lower Serum and Liver Triglyceride Levels in Rats

This is the authors' abstract. We don't add key points for this paper.

We investigated the effects of dietary soybean peptides, particularly low-molecular-weight peptides, on serum and hepatic concentrations of lipids in rats. Soybean protein isolate (SPI) was digested with protease to produce low-molecular-weight peptides (LD) or a mixture of high- and low-molecular-weight peptides (HLD). Rats were fed diets containing 20% casein, SPI, LD or HLD as a nitrogen source, with or without 0.5% cholesterol, for 2 wk. Next, rats were fed cholesterol-free diets containing 0%, 5%, 10%, or 20% LD at the expense of casein for 2 wk. Serum triglyceride levels were the lowest in the LD group, and liver triglyceride levels were significantly lower in rats fed SPI and LD/HLD diets than in those fed casein diets, both in the presence and absence of dietary cholesterol. In addition, dietary LD significantly lowered serum and liver triglyceride levels in a dose-dependent manner. These results suggest that low-molecular-weight soybean peptides have a potent hypotriglyceridemic effect and may be beneficial for improving lipid metabolism.