Galactomannan and glucono-δ-lactone affect calcium absorption effect of xylooligosaccharide in rats

We investigated the effect of dietary saccharides on the absorption of calcium in rats. Calcium L-lactate was used as a source of calcium. We used the test diets containing xylooligosaccharide(XO), Galactomannan(GM)and Glucono-δ-lactone(GL). In experiment 1, five-week-old rats, were divided into four groups. Each group was fed a control diet or a test diet(1.2%XO or 1.0%GM or 0.7%GL)for 3 weeks. In exp.2, each group of rats was fed a control diet or a test diet(1.2%XO or 1.2%XO・1.0%GM or 1.2%XO・0.7%GL). In exp.3, rats were divided into two groups, and were fed a control diet or a test diet(1.2%XO・1.0%GM・0.7%GL). In exp.4, rats were divided into four groups and each group was fed a control diet or a test diet(5%XO or 5%GM or 5%GL). All diets contained the same amounts of Ca(0.52%)and phosphorus(0.40%). In exp.1 and exp.2, Ca absorption ratios in the test diet did not differ from those in the control diet group. In exp.3, Ca absorption ratio and Ca contents of femur were significantly increased in the test diet group. In exp.4, Ca absorption ratio was significantly increased in the 5%XO diet group. In the XO diet, a positive effect of Ca absorption was observed in the 5%XO diet group, but not in the 1.2%XO diet group. The addition of 1.0%GM and 0.7%GL to 1.2%XO promoted Ca absorption effect of 1.2%XO. These results suggest that increased Ca absorption by mixture of XO, GM and GL was due to their synergistic effect