Proximate Composition and Dietary Fiber Analyses of Heat-dried Pericarp of Citrus maxima and its Effect on Blood Glucose Levels in Rats

This study identified functional ingredients in the pericarp, both the albedo and the flavedo, of Citrus maxima, which is a special product of Kumamoto Prefecture, Japan. First, the proximate composition and dietary fiber contents of the heat-dried pericarp of C. maxima were determined. It was found that the heat-dried pericarp contained 15.0 g/100 g of soluble and 18.8 g/100 g of insoluble dietary fibers. Next, the effect of the heat-dried pericarp on blood glucose levels in male Wistar rats was investigated. The results indicated that the heat-dried pericarp contained components capable of both increasing and decreasing blood glucose levels.