ANTIBACTERIAL AND CYTOTOXIC ACTIVITIES OF Carica papaya L. (PAPAYA) SEEDS

Abstract

The crude ethanolic and methanolic extracts of Carica papaya L. seeds were investigated to evaluate their antibacterial and cytotoxic potentialities. The average zone of inhibition for ethanolic extract of C. papaya seed ranged 6.25 – 9.75 mm for 500 μg/disc and 8 -14.75 mm for 1000 μg/disc. With methanolic extract the zone of inhibition ranged 7.75 – 8.50 mm for 500 μg/disc and 11.25 – 14.50 mm for 1000 μg/disc. Again from minimum inhibitory concentration (MIC) assay (Resazurin assay), the MIC was found to be 0.625 mg/ml for ethanol and 0.312 mg/ml for methanol extract. The minimum bactericidal concentration (MBC) was found to be 1.25 mg/ml for ethanol and 0.625 mg/ml for methanol extract. Compared to vincristine sulphate (with LC50 of 1.20 μg/ml) both ethanolic and methanolic extract of C. papaya seeds showed toxicity higher than 100 μg/ml. The study affirmed potential antibacterial property of C. papaya seed extracts with mild cytotoxic activity. These findings could be correlated with the traditional medicinal uses of papaya seeds and showed the rationale for further investigation for screening out the possible bioactive constituents.