Inhibition effect against 20 bacteria and 4 cell lines of methanol and water extract from pawpaw (Asimina triloba [L.] Dunal) cultivated in Korea

Pawpaw (Asimina triloba [L.] Dunal) is a subtropical plant belonging to the Annonaceae family and is different from papaya. Except for the fruit, the remaining parts are used for medicinal purposes, but little is known about them in Korea. In this study, antibacterial activities of pawpaw extracts derived using methanol and water solvents on roots, twigs, and leaves were investigated by determining the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) against 20 bacterial strains. Most of the extracts produced an inhibition zone at 50 mg/disc against all tested microorganisms. In particular, pawpaw twigs and root methanolic extracts (PTM and PRM, respectively) showed potent antibacterial effects superior to those of other samples. The anticancer activities of the extracts were investigated using a cytotoxicity assay against 4 cancer cell lines (human fibrosarcoma cells HT-1080, human cervical cancer cells HeLa, human liver cancer cells HepG2, and human gastric cancer cells AGS). PTM showed the strongest inhibition activity against HT-1080 (IC50=64.57 μg/mL), HepG2 (IC50=68.99 μg/mL), and AGS (IC50=70.48 μg/mL) cells. PRM exhibited the highest antiproliferative activity for HeLa cells, with an IC50 value of 126.17 μg/mL. These findings suggest that the pawpaw twigs and root extracts have medicinal value and can be further investigated as biomaterials in various fields.