28-Day Repeated Oral Dose Toxicity Study of an Aqueous Extract of Gryllus Bimaculatus in Sprague-Dawley Rat

This study was performed to demonstrate a No Observed Adverse Effect Level (NOAEL) for an aqueous extract of Gryllus bimaculatus. According to other studies, using dried material or extract with ethanol or methanol determined a NOAEL dose of 1000 mg/kg or 5000 mg/kg in rats. Therefore, the Gryllus bimaculatus groups were administered orally at doses of 0, 1000, 2000, and 3000 mg/kg for four weeks. Two-week recovery groups were administered at doses of 0, and 3000 mg/kg. During administration and recovery period, the animals were observed for clinical signs, change of body weight, food consumption, hematology, and clinical chemistry. Rats in each group were periodically sacrificed, and organs were weighed and examined histologically. No difference arose between any of the dosage groups and the control group in clinical signs, histopathological examination, hematology, or clinical chemistry. In conclusion, 3000 mg/kg is a NOAEL dose for Gryllus bimaculatus extracts in Sprague Dawley rats.