Safety evaluation of polyphenol-rich extract from bamboo shavings.

In this paper, a number of acute and subchronic toxicological tests were documented to evaluate the safety of a polyphenol-rich ethanol extract of bamboo shavings (EEBS). (i) Acute toxicity test: The oral maximum tolerated dose (MTD) of EEBS was above 20 g/kg body weight for mice, thus the amount can be seen as practically non-toxic. (ii) Mutagenicity test: No mutagenicity was detected according to the negative experimental results of Ames test, micronucleus test on bone marrow cell in mice and abnormality test on mice sperms. (iii) 30 days feeding study: There were no treatment-related toxic effects when EEBS were at levels of 2.50, 5.00, or 10.00 g/kg/day and no adverse effects of EEBS had been observed in these studies. The no-observed-adverse-effect level (NOAEL) of the extract was 10.00 g/kg/day during the 30 days. In addition, no significant distinctions were observed in hematology values, clinical chemistry values and organ/body weight ratio (P > 0.05). In conclusion, EEBS is safe and the results support the use of EEBS for various foods.