Effects of Dietary Chitosan on Blood and Tissue Levels of Lead, Iron, Zinc, and Calcium in Lead Administered Rats

摘要

Chitosan, which is a biopolymer, composed of glucosamine units linked by beta-l, 4 glycoside bonds, is rich in shells of crustacean such as crabs and shrimps. We examined effects of dietary chitosan on blood and tissue levels of lead, iron, zinc and calcium in lead administered rats. Male Sprague-Dawley rats were divided into 4 groups (n-32). Basal diet group was fed 3% cellulose diet and lead administered groups were fed 0%, 3% and 5% chitosan diets, respectively for 8 wks. To lead administered groups, lead (20 mg/day) was given three times per week by oral injection. Blood, liver, kidney and femur were collected for lead, iron, zinc, and calcium analyses. There was no significant difference in weight gain and food intake among groups. Blood and femur lead levels were lower in lead administered groups fed 3% and 5% chitosan diets than in lead administered control (0% chitosan diet) group (p<0.05). Blood and liver levels of iron and zinc in lead administered group fed 5% chitosan diet were significantly lower than those in basal diet group (p<0.05), but those in lead administered group fed 3% chitosan diet were not significantly different with those in basal diet group. These results show that chitosan diets have beneficial effects on lowering theaccumulation of lead, but high chitosan diet may have negative effects on mineral levels.