Uji Aktivitas Antibakteri Ekstrak Etanol dan Fraksi Etil Asetat Beras Hitam (Oryza Sativa L.) Terhadap Bakteri Staphylococcus aureus dan Escherichia coli

Jurnal Farmasi (Journal of Pharmacy), October 2025

Abstract

Black rice (Oryza Sativa L.) is a local rice that produces anthocyanins with high intensity in the aleurone and endospremia so that the color of the rice becomes intense purple to black. Black rice contains flavonoids, tannins, and alkoloids. This study aims to determine the antibacterial activity of ethanol extract and ethyl acetate fraction of black rice (Oryza Sativa L.) against Staphylococcus aureus and Escherichia coli bacteria. Black rice powder was macerated using 96% ethanol, then fractionated using ethyl acetate solvent. Testing the antibacterial activity of ethanol extracts and ethyl acetate fractions was carried out using the disc diffusion method. Diffusion method testing using concentrations of 25%, 30%, and 35% using positive control Ciprofloxacin 5µg against Staphylococcus aureus and Escherichia coli bacteria. The results of antibacterial activity testing showed that ethanol extract and ethyl acetate fraction of black rice can inhibit bacterial growth with inhibition. The ethyl acetate fraction with a concentration of 35% is the most active fraction with an average inhibition zone diameter of 17.47 mm on Staphylococcus aureus bacteria while on Escherichia coli bacteria the average inhibition zone diameter of the ethyl acetate fraction is 14.52 mm. Based on one way anova data analysis test, each concentration of ethanol extract and ethyl acetate fraction showed a significant difference in antibacterial activity and did not have the ability of anti-bacterial activity. Based on one way anova data analysis test, each concentration of ethanol extract and ethyl acetate fraction showed a significant difference in antibacterial activity and did not have the ability of antibacterial activity equivalent to Ciprofloxacin positive control with sig. (P<0.05).