Hsiao Ping Lee has completed her PhD from National TsingHua University. She is working as a Quality Assurance Manager in RMRI.


A new species, Chitinibacter tainanensis capable of converting chitin into N-acetyl glucosamine (NAG), was discovered in the previous work. It was found totally new that NAG could be produced by aerobic fermentation. Most of all, the broth of fermentation could be separated and further purified to the desired NAG powder with the purity of greater than 99%. The applications of NAG in the fields of food, cosmetics and pharmacy have been well defined. However, the safety of NAG produced by this novel bacterium should be thoroughly considered. In this work, a 90-day oral test in rat was conducted to justify the safety concern on NAG administration. A total of 40 male and female Wister rats were equally divided into 4 groups. Each group was given orally with NAG at dosage of 0 (D.I. water), 1.5, 3 or 5 g/kg bw/day separately. All animals survived to the end of study. The observations of overall health, food consumption, body weight, clinical pathology parameters (hematology, blood chemistry and urinalysis) and organ weights showed no significant differences among all groups. Microscopic examinations also showed that there were almost the same between control and treatment groups at the aspects of ophthalmic or histological observation. The results showed that the no-observed-adverse-effect level (NOAEL) of NAG for rat was 5 g/kg bw/day, equivalent to 100 times of the recommended dose for human (3 g/60 kg bw/day). NAG produced by the new species, C. tainanensis, is considered to be safely used as food supplement.