Safety evaluation of short-term exposure to chitooligomers from enzymic preparation.

Chitooligomers have significant application to the development of functional foods. This paper evaluated systematically the safety of chitooligomers, which were prepared by enzymatic depolymerization of chitosan. The oral maximum tolerated dose of this chitooligomes was more than 10 g/kg body weight in mice. It had no mutagenicity judged by negative experimental results of Ames test, mouse bone marrow cell micronucleus test and mouse sperm abnormality test. A 30-day feeding study shows that no abnormal symptoms and clinical signs or deaths were found in rats during the test. There were no significant difference in body weight, food consumption and food availability of rats in each test group. No significant differences were found in each hematology value, clinical chemistry value and organ/body weight ratio, either. No abnormality of any organ was found during histopathological examination. It is concluded that short-term ingestion of chitooligomers is of non-toxicity.