Cytotoxicity study and antioxidant activity of crude extracts and SPE fractions from Carica papaya leaves

Millions of people in various traditional systems resorted to the use of medicinal plants for their ailments and recently, substances with antioxidant properties have been given unprecedented attention as possible therapeutic and preventive agents. The present study focused on cytotoxicity and antioxidant assessment of crude and fractions of C. papaya leaves as an important medicinal plant. Cytotoxicity was measured using the MTS colorimetric assay while antioxidant activity of the crude water extract and solvent fractions obtained from C.papaya leaves was evaluated in terms of capacity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals. The crude water extract showed no cytotoxic effects within the tested concentrations compared with methanol and ethanol extracts. C.papaya fraction 1, 2 and 3 showed no cytotoxicity effect up to 2000 μg/ml, whereas fraction 4 and 5 showed no cytotoxicity up to 1000 μg/ml. The crude extract and the fractions showed considerable antioxidant activity with the most potent radical scavenger in the order of fraction 3, fraction 2, fraction 1, crude water, fraction 4 and fraction 5, respectively. The results obtained from this study provide a clear rationale for the medicinal uses of C.papaya.