Uji Aktivitas Antibakteri Ekstrak Etanol Daun Kersen (Muntingia calabura L.) terhadap Bakteri Escherichia coli
Kersen leaves contain phenolic compounds, flavonoids, tannins, alkaloids, saponins, and steroids. This study aims to determine the antibacterial activity of ethanol extract of leaves against Escherichia coli bacteria and to determine the potential antibacterial activity compared to gentamicin. Antibacterial activity testing was conducted using the well diffusion method with 7 treatment groups, namely 25%, 50%, 75%, and 100% concentrations of ethanol extract from kersen leaves, gentamicin 10μg/20μl as the positive control, water for injection as the negative control, and 96% ethanol as the solvent control. Each treatment was inoculated with bacteria, then dripped with ethanol extract of kersen leaves, incubated at 37°C for 24 hours, and the data obtained in the form of inhibition zones were measured and analyzed for sensitivity based on CLSI with gentamicin as a comparison. Antibacterial activity showed the diameter of the inhibition zone on E. coli bacteria at concentrations of 25%; 50%; 75% and 100% of kersen leaf extract measuring 13.66±0.16mm; 14.58±0.22mm; 15.16±0.15mm and 16.46±0.15mm, with intermediate categories at concentrations of 25% and 50% and sensitive at concentrations of 75% and 100%. Gentamicin showed an inhibition zone diameter of 17.66±0.20mm with a sensitive category according to CLSI. The results of the inhibition zone indicated a significant difference between the extract treatment groups and the positive control gentamicin (sig0.05). Based on the research results, it can be concluded that the ethanol extract of kersen leaves has antibacterial activity against E. coli bacteria, but its potency is not comparable to gentamicin.