Abstract
The effects of wakame sporophyll (Undaria pinnatifida) on the structure of the digestive organs and on the plasma cholesterol concentration were investigated in rats. Male Sprague-Dawley rats were fed on diets containing 3 % of wakame sporophyll (in experiment 1) or sodium alginate extracted from wakame sporophyll (in experiment 2) for 5 weeks. In experiment 1, the relative tissue weight of the stomach, small intestine, cecum and colon did not vary between the two dietary treatments. The bound water content of the cecal contents of rats fed on wakame sporophyll was, however heavier than that of rats fed on the control diet. This may indicate that the intake of wakame sporophyll increased the water-holding capacity of the cecal contents. No histological difference in the cecum between the wakame sporophyll and control groups was apparent. In experiment 2, the plasma cholesterol concentration was significantly decreased in those rats fed on sodium alginate extracted from wakame sporophyll. However, intake of the diet containing 3 % wakame sporophyll did not effect the plasma cholesterol concentration in experiment 1.
