Antibacterial, Antioxidant Activities and Phytochemical Constituents of Jatropha curcas L. Leaves

Abstract

The study was carried out for investigation of antibacterial and antioxidant activities along with phytochemical analysis of leaf extracts of Jatropha curcas L. Extraction was done by using methanol and acetone solvents. Antibacterial activity was analysed by Agar well diffusion method against four human pathogenic bacteria, which included two Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Streptomycin was taken as a standard and positive control. Both methanol and acetone leaf extracts showed higher inhibition against S. aureus (19.98 mm and 18.75 mm for methanol and acetone respectively, at 100 % conc.). Antioxidant activity was determined by using DPPH (2, 2- diphenyl-1- picrylhydrazyl) free radical scavenging assay and Reducing power assay. BHT (Butylated hydroxytoluene) was used as standard for both methods. Highest free radical scavenging activity was shown by leaf extract with IC50 value of 200.84 μg/ml for methanol leaf extract, and for reducing power method, methanol leaf extract showed antioxidant activity with EC50 value of 714.6 μg/ml. Phytochemical screening showed the presence of alkaloid, flavonoid, terpenoid, carbohydrate and protein. Gas Chromatography and Mass Spectrometry (GC-MS) results of leaf methanol extract showed 28 phytoconstituents with squalene [C30H50 (2,6,10,14,18,22-h Tetracosahexaene, 2,6,10,15,19,23- Hexamethyl)] (37.84%), as major compound and it possesses antioxidant, antitumour properties and also used in cosmetic dermatology. In conclusion, the particular study demonstrated the biological potency of leaf of J. curcas as antibacterial, antioxidant agent and provide support to its use as a traditional medicinal plant, and further investigations can be done to check its therapeutic potential by isolating the phytochemical constituents.