Effects of Soyoligosaccharide on Lipid Metabolism in Rats Fed the High Fat or Low Fat Diet

This study investigated the effects of soyoligosaccharide consumption on lipid profile of plasma, liver and feces and immune responses in Sprague-Dawley male rats. Sixty male Sprague-Dawley rats 4-wk-old were provided the soyoligosaccharide containing diets for 4 weeks (0, 100 g/kg diet); each of these diets was supplemented with either 70 or 200 g fat/kg diet, giving a total of 4 experimental groups. The effect of weight reduction was most significantly observed in the group fed low fat and soyoligosacchairde diet. The plasma total lipid and cholesterol contents were not changed by either fat proportion or soyoligosaccharide supplementation in the diets. Also the plasma triglyceride lowering effect by soyoligosaccharide was not observed in rats fed either low fat or high fat diet. However, the significant decrease in TG contents was found with rats fed high fat diets compared to the control/no soyoligosaccharide diet. Elevation of plasma LDL-cholesterol and reduction of HDL-cholesterol by feeding high fat diet was not altered by supplementing soyoligosaccharide. This was also applied to the liver lipid profiles. The significant increases in liver total lipid, triglycerides and cholesterol by high fat diet was not abolished by feeding soyoligosaccharide. However, the desirable effects of feeding soyoligosaccharide were found with total lipid and cholesterol excretion through feces in rats fed high fat diets. Immune organ weights and spleen cell proliferations did not affected by experimental diets. These results demonstrated that soyoligosaccharide intakes increased the lipid output via feces, especially in rats fed the high fat diet, but more researches are needed on immune responses.

Effects of Soyoligosaccharide Intake on Fecal Bifidobacteria and Lipid Concentration in Korean Young Women

This study investigated the effects of soyoligosaccharide consumption on feces bifidobacteria proliferation and feces lipid profiles in Korean young women. Eight healthy young women (25 - 34 years) were fed 15 g/day of soyoligosaccharide solution, containing 3 g of oligosaccharide as form of raffinose and starchyose, for 15 days with their habitual meals. Soyoligosaccharde intake increased the numbers of fecal total bacteria significantly until 10 days (p < 0.05) and the numbers of fecal bifidobactreia were significantly increased until 15 days (p < 0.05). The fecal pH was significantly decreased (p < 0.05) by soyligosaccharide intake. Fecal lipid concentration showed the trend to increse, especially fecal triglyceride level was significantly increased by soyoligosaccharide intake (p < 0.05). The water contents of feces, the amount of feces, evacuation frequency and taking time to evacuation were not affected by soyoligosaccharide intake. The color of feces changed to yellow-brown, and hardness of stool and effort to evacuation were reduced by soyoligosaccharide intake. These results suggest that soyoligosaccharide intake (3 g/day) in young women improved the gut microflora and fecal lipid profile. Therefore, soyoligosaccharide has a potential to be used as one of the promising prebiotics, and controlled trials with larger sample sizes and longer duration are need to be studied further.