Abstract:

Objective: To evaluate the food safety of β-glucan from the fermented mycelia of Grifola frondosa strain GF-932. Methods: Maximum limited amount method was used for the evaluation of acute toxicity. Microorganism reverse mutation test (Ames test) and mouse bone marrow cell micronucleus test were used to explore mutagenesis. Mouse spermatogonium chromosomal aberration test and sperm malformation test were used to assess reproductive toxicity. After 30-day feeding, rat body weight, food intake, blood cell and biochemical index were determined. Results: according to acute toxicity test, the LD50 ofβ-glucan from fermented the mycelia of Grifola frondosa was more than 20 g/kg bw. Negative results were observed in Ames test and mouse bone marrow cell micronucleus test and spermatogonium chromosomal aberration test and sperm malformation test. Through 30-day feeding, the growth and development status of rats was improved. Compared with the control group, body weight, food utilization rate, organ-weight ratio, hematology and serum biochemical indices in rats fed the polysaccharide from Grifola frondosa at different dosages did not exhibited an obvious difference (P > 0.05). Conclusion: β-glucan from Grifola frondosa is nontoxic and has no genetic toxicity. It does not have any negative effect on the growth and development status of animals.

Key words: Grifola frondosa, β-glucan, acute toxicity test, genetic toxicity