A Comparative Study on Antioxidant and Cytotoxic Potentials of Methanol Extract of Jatropha curcas Seeds and Leaves

Many medicinal plants have been reported to exhibit protective effects against many physiological diseases as a result of their phytochemical components which are effective antioxidants. This study was aimed at comparing the phenolic and flavonoids contents, antioxidant and cytotoxic activities of methanol extract of Jatropha curcas seeds and leaves. The cytotoxicity level of J. curcas was assessed using the brine shrimp lethality test (BSLT). The antioxidant activity was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), nitric oxide scavenging activities, 2, 2’-azino-bis-(3 ethyl benzothiazoline-6-sulphonic acid (ABTS) + scavenging activities and total antioxidant capacity. The total flavonoids and total phenols content (TPC) were carried out using aluminum chloride and Folin-Ciocalteu assay respectively. The results showed that J. curcas leaves have significant higher phenolic and flavonoids contents than the seeds. The total antioxidant capacity and FRAP were also significantly higher in the leaves than the seeds of J. curcas. Furthermore, the DPPH, ABTS and Nitric oxide scavenging activities were significantly higher in the leaves than the seeds. The J. curcas leaves have a higher LD50 than the seeds. In conclusion, this study suggests the antioxidant potency as well as the safety of the crude methanol extract of the leaves of J. curcas over the seeds. Keywords: Jatropha curcas, antioxidant, cytotoxicity, flavonoids, brine shrimp lethality test, total phenolic compounds