A chemical and toxicological study of the tuber extracts of Rhoicissus revoilii Planch. (Vitaceae): A Comorian plant used as a pesticide

This study aimed to assess the acute toxicity of Rhoicissus revoilii Planch tuber extracts. This plant from the Vitaceae family is used to treat various pathologies and as a pesticide in the Comoros. From dried tuber powder previously treated with hexane, a methanolic extract (ME) was obtained with a yield of 20.33%. Phytochemical screening of the powder revealed the presence of flavonoids, tannins, polyphenols, coumarins, triterpenes and steroids. The toxicity of ME was assessed in mice and cold-blooded animals. In mice, symptoms of intoxication by the intraperitoneal (i.p.) and oral routes mainly included decreased motor activity, muzzle itching, diarrhoea, and increased respiratory rate. The LD₅₀ (24 h) of ME in mice was estimated to be between 21.29 and 22.3 mg/kg body weight (b.w.) by the i.p. route. By the oral route, it was estimated to be between 273 and 275 mg/kg b.w. When administered by these two routes, ME caused dose-dependent histopathological lesions in the liver, lungs and kidneys. The LC₅₀s were estimated to be 7.491 μg/ml, 8.055 μg/ml and 685 μg/ml, respectively, for alvins, legless frog tadpoles and mosquito larvae at stage three of development.