Effect of dietary carboxymethyl chitosans on the levels of iron, zinc and copper in mice

Three carboxymethyl chitosan samples were prepared by the carboxymethylation of chitosans with different molecular weights (Mw). These samples (0.75%, w/w) in diet were fed mice for 30 days. Afterwards no pathological symptoms, clinical signs or deaths were observed. The body weights of mice in carboxymethyl chitosan groups and control group showed no significant difference. These carboxymethyl chitosan samples did not decrease the level of copper in the tested mice's organs. However, the level of iron in the tested mice's livers and lungs, and the level of zinc in the tested mice's livers, lungs, hearts, spleens, thymuses and kidneys were significantly decreased by oral administration of these samples.