Abstract

The study was conducted to screen for the phytochemical constituents of Cassia sieberiana. The acute toxicity value and the effect of the aqueous extract of the pods of C. sieberiana on serum transaminases and alkaline phosphatase (ALP) were also measured in rats after five weeks of daily oral administration of grade doses (200 - 1600 mg/kgbody weight) of the extract. Phytochemical analysis of the C. sieberianapods pulp (fruit) revealed the presence of tannins, alkaloids, saponins, steroids, flavonoids, phlobatannins, cardiac glycosides, cyanogenic glycosides and reducing sugars. The concentration of tannins and saponins were found to be much higher than the other phytochemical components. The result of the oral acute toxicity study showed that LD₅₀ of the extract is 1950 mg/kg, indicating that the extract is of low toxicity. In this study, the extract used had caused a significant elevation (P<0.05) (27.60 ± 1.25^b) of serum levels of ALT in the group that received the highest dose (1600mg/kg body weight) of the extract and a significant increase (P<0.05) (43.00 ± 1.14^b, 49.40 ± 2.71^c, 52.60 ± 3.90^d, 60.00 ± 3.55^e) increase in the serum level of AST in all the treated group when compared to the control rats (22.80 ± 0.66^a). The result also show a statistically significant (P<0.05) (208.80 ±11.95^b, 220.20 ± 8.47^c, 234.80 ± 4.33^d) increase in the serum level of ALP in those groups that received 400,800 and 1600mg/kg body weight of the extract when compared to the control rats (146.80 ± 7.20^a). From these result, even though the pods (fruit) of C. sieberiana has been reported to have medicinal value and despite the fact that the calculated LD₅₀ of this fruit indicated a low toxicity, this study has   shown that using the extract at a high dose such as 400 – 1600 mg/kg body weight for a long period can cause liver damage. We therefore conclude that the plant should be taken at a very low dosage ≤ 200 mg/kg body weight and should not be taken over a long period of time.

Key words: Phytochemical, toxicity, transaminases, alkaline phosphatase, Cassia sieberiana.