Effects of Water-Soluble and -Insoluble Fractions of Spirulina on Serum Lipid Components and Glucose Tolerance in Rats

Abstract

Effects of Spirulina on serum lipid components and glucose tolerance in rats were studied. Experiment diets were prepared with 20% Spirulina water-soluble fraction (SS), with 20% Spirulina waterinsoluble fraction (SI) or with 18% casein (CN). Each group of 8 male Sprague-Dawley rats were fed with SS, SI and CN diets for 4 weeks in individual cages. Fasting serum glucose levels were measured on the 7th and 28th days, and glucose tolerance on the 28th day. The nitrogen balance was also examined during the last 3 days. Total-cholesterol, HDL-cholesterol and triglycerides in serum were measured on the 28th day when the rats were sacrificed. No effect was observed on either growth or feed efficiency among all groups. The highest ratio of HDL-cholesterol to other cholesterols and the low fasting serum glucose levels were observed in the SS group. In the glucose tolerance test, the elevation of glucose seemed to be more suppressed in the SI group than in the SS group.