ANTIMICROBIAL ACTIVITY, PHYTOCHEMICAL SCREENING AND TOXICITY OF JATROPHA CURCAS L. AND RICINUS COMMUNIS L. SEED OIL

Abstract

ABSTRACT Jatropha curcas and Ricinus communis are members of the Euphorbiaceae that have been known for their ethno-medicinal uses. The aim of this study was to investigate the antimicrobial activity, phytochemical constituents and toxicity of J. curcas and R. communis seed oil. The antimicrobial activity against Escherichia coli, Salmonella Typhi, Staphylococcus aureus, Aspergillus flavus and Aspergillus niger was carried out using Agar Well Diffusion method at 100, 200, 300 and 400 mg/mL. The toxicity was assessed according to Lorke’s method for acute toxicity testing and the sub-acute toxicity was conducted by daily oral dosing (10, 300 and 600 mg/kgb.wt) of Wistar rats for 28days. Haematological, biochemical analyses of blood samples and histopathology of the liver and kidney were evaluated. The highest antimicrobial activity was exhibited by J. curcas seed oil against S. aureus with mean inhibition zone of 32±3.17 mm and the lowest activity of J. curcas was against A. niger with mean inhibition zone of 10±0.57 mm. Similarly, the highest antimicrobial activity of R. communis seed oil was against S. aureus with mean inhibition zone of 28±2.30 mm and the lowest activity of R. communis was against A. niger with mean inhibition zone of 8±4.61 mm. The LD5 of J. curcas seed oil was greater than 5000 mg/kg b.wt and 3807 mg/kg b.wt was the LD50 of R. communis seed oil. The result of the haematological and biochemical blood test of rats administered J. curcas seed oil showed decrease in the TWBC, PLC and L while the level of Hb, PCV, MCV, MCH, MCHC and RBCs increased. Generally, increase in the level of AST, ALT, ALP, total bilirubin, urea, creatinine, cholesterol and TAG was observed in the 600 mg/kg bw.t group but their level in the 10 and 300 mg/kg b.wt groups were comparable with the control group. In contrast, the level of total protein and albumin decreased. The result of the effect of R. communis seed oil on the haematological and biochemical indices showed increased level of Hb, PCV, MCV, MCH, MCHC, PLC, L, AST, ALT, ALP, total bilirubin, urea, creatinine, cholesterol and TAG in 300 and 600 mg/kg bw.t group, there level in 10 mg/kg bw.t group was also comparable to the control group. Similarly, the level of total protein and albumin decreased. The histological evaluation revealed distortion in the cyto-architecture of the liver and kidney of rats administered 600 mg/kg bw.t of J. curcas seed oil, 300 and 600 mg/kg bw.t of R. communis seed oil. It can be concluded from this study that both seed oil can be used in the treatment of diseases associated with the tested isolates but cautious should be taken in their usage at high doses for prolonged time with emphasis on R. communis seed oil. The findings provide the basis for further study on the wounding healing activity of the seed oil.