Acute and 13 weeks subchronic toxicological evaluation of naringin in Sprague-Dawley rats

• We conducted acute and subchronic oral toxicity studies of naringin.
• In the acute study, the oral LD50 was >16 g/kg body weight.
• No treatment-related toxicological changes were observed in the subchronic study.
• Naringin decreased the body weights of rats.
• The oral NOAEL of naringin was >1250 mg/kg/day in rats administrated for 13 weeks.

Naringin is widely distributed in plant foods and has not previously been evaluated for safety through standard in vivo toxicological studies. In the present study, acute and subchronic oral toxicity studies of naringin were designed and conducted in Sprague-Dawley (SD) rats. Acute oral administration of naringin was done as a single bolus dose up to 16 g/kg and subchronic toxicity study for 13 weeks was done by oral administration at doses of 0 (control), 50, 250 and 1250 mg/kg in SD rats. There were no mortality, adverse clinical signs, abnormal changes in body weights or food consumption, toxicologically relevant changes in hematology, clinical biochemistry and macroscopic findings during 14 days of the acute toxicity study. During the subchronic oral toxicity study, no mortality and toxicologically significant changes in clinical signs, food consumption, opthalmoscopic examination, hematology, clinical biochemistry, serum sex hormone, macroscopic findings, organ weights and histopathological examination except for slight body weight decrease were noted and attributed to naringin administration. These observations suggest that naringin is practically non-toxic for SD rats in oral acute toxicity study and the no-observed-adverse-effect-level (NOAEL) of naringin in rats is greater than 1250 mg/kg/day when administered orally for 13 consecutive weeks.