Ninety-day oral toxicity study of rice-derived γ-oryzanol in Sprague Dawley rats

A 90-day oral toxicity study of gamma-oryzanol, a rice-derived triterpenoid ferulate, was performed by oral gavage administration to male and female Sprague-Dawley rats at doses of 0, 1000, and 2000 mg/kg body weight/day. All rats administered gamma-oryzanol survived throughout the study period. Both male and female rats showed no toxicologically significant changes of the general signs, examination findings, body weight, food consumption, functional observational battery results, ophthalmological findings, urinalysis, hematology tests, clinical chemistry tests, organ weights, and necropsy findings. Moreover, there were no histopathological changes related to administration of gamma-oryzanol in males and females from the 2000 mg/kg body weight/day group. In conclusion, the no observed adverse effect level (NOAEL) of gamma-oryzanol exceeded 2000 mg/kg body weight/day for both male and female rats under the conditions of this study. (C) 2016 The Authors. Published by Elsevier Ireland Ltd.