Acute and Sub-chronic Toxicity Studies of Methanol Leaf Extract of Cassia singueana F. (Fresen) in Wistar Rats

The aim of this study was to evaluate the toxicity profile of methanol leaf extract of Cassia singueana (fabaceae) in wistar rats. Fresh leaf of the plant was shade dried and pulverized to powder after which it was subjected to maceration with methanol and 9.2% yield was obtained at end of the extraction process. An acute toxicity study was carried out using lork’s method and sub-chronic toxicity study was also carried out using OECD guideline. In the acute toxicity study, the first phase of the method, nine (9) wistar rats were randomly divided into three groups (1-3) of three (3) animals each and they received 10,100 and 1000 mg/kg (po) Cassia singueana methanol leaf extract respectively and in the second phase four (4) animals were divided into four groups of one animal each which received 1200, 1600, 2900 and 5000 mg/kg (po) of extract respectively. In the sub-chronic toxicity study twenty (20) animals were divided randomly into four group each containing five animals, the first, second, third and fourth group received distilled water, 200, 400 and 800 mg/kg extract (po) respectively. There was no mortality observed in phase 1 of acute toxicity and in phase II there was mortality at 2900 and 5000 mg/kg group. The oral administration of methanol leaf extract of Cassia singueana for 28 days did not produce significant alteration in the renal function indices. The histological section of the rats indicates normal glumeruli and regular renal tubules. Also, this study reveals no significant increase in the level of liver enzyme. Also, the histology section reveals normal central vein and regular hepatocyte separated by sinusoid. The haematopoetic indices reveal no destruction of Red Blood Cell and no change in the rate of production of the RBCs and other haematopoetic parameters. The histology of the rat’s brain revealed no deleterious effect. It can be concluded that, the methanol leaf extract of Cassia singueana is relatively non- toxic.