Abstract

PHYTOCHEMICAL PROFILING AND ANTIBACTERIAL EFFICACY OF ETHYL ACETATE EXTRACT OF CARICA PAPAYA SEEDS (VIA LIQUID–LIQUID EXTRACTION): A KIRBY–BAUER METHOD INVESTIGATION

*Pinki Verma, Girish Kumar K. S., Pranya H. C., Gagan N. V., Chethan M., Chaithanya D., Keerthi

Abstract

Aim: This study aimed to investigate the phytochemical profile and evaluate the in vitro antibacterial activity of the ethyl acetate extract of Carica papaya seeds, obtained via liquid-liquid extraction (LLE), against selected Gram-positive and Gram-negative bacteria. Methods: Dried and powdered papaya seeds were subjected to LLE using ethyl acetate as the solvent. The extract was screened for major phytochemical constituents using standard qualitative tests. The antibacterial efficacy was assessed against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) using the Kirby-Bauer disc diffusion method. A concentration of 1 g/mL of the extract was tested, with Amoxicillin (10 µg/disc) as the positive control and ethyl acetate as the negative control. The zones of inhibition were measured after 24 hours of incubation at 37°C. Results: Phytochemical analysis confirmed the presence of alkaloids, flavonoids, tannins, saponins, and carbohydrates. The ethyl acetate extract exhibited significant antibacterial activity against S. aureus, producing a mean inhibition zone of 15 mm, which was larger than that produced by the standard Amoxicillin (10 mm). In contrast, no zone of inhibition was observed against E. coli for both the extract and the standard drug under the tested conditions. Conclusion: The ethyl acetate extract of Carica papaya seeds demonstrates potent and selective antibacterial activity against Gram-positive S. aureus, outperforming Amoxicillin in this assay. This activity is likely due to its rich phytochemical composition. The lack of effect on E. coli highlights its spectrum-specific action. These findings validate the traditional use of papaya seeds and suggest their potential as a source for developing natural antibacterial agents against Gram-positive infections, warranting further investigation into active compound isolation and the mechanism of action.

Keywords: Carica papaya, Papaya seeds, Antibacterial activity, Liquid-liquid extraction, Phytochemicals, Staphylococcus aureus, Escherichia coli.