<![CDATA[The increasing incidence of infections caused by Staphylococcus aureus and the growing problem of antibiotic resistance have encouraged the exploration of natural sources as alternative antibacterial agents. Kaffir lime (Citrus hystrix) leaves are known to contain various secondary metabolites with potential antibacterial properties. This study aimed to evaluate the antibacterial activity of kaffir lime leaf extract against Staphylococcus aureus and to analyze the effect of different extract concentrations on the diameter of inhibition zones. The extract was prepared using a maceration method with 96% ethanol, followed by solvent evaporation to obtain a concentrated extract. Antibacterial activity was assessed using the disc diffusion method with extract concentrations of 5%, 10%, 15%, and 20%. Chloramphenicol was used as a positive control, while 96% ethanol served as a negative control. The results showed that all extract concentrations produced inhibition zones ranging from 6.24 to 6.62 mm, which were classified as weak antibacterial activity and did not demonstrate a significant concentration-dependent effect. In contrast, the positive control exhibited a markedly larger inhibition zone of 32.14 mm, while the negative control showed no inhibitory effect. These findings indicate that the ethanol extract of kaffir lime leaves exhibits limited antibacterial activity against Staphylococcus aureus under the experimental conditions. Further studies involving extraction optimization or purification of active compounds are recommended to enhance its antibacterial potential.]]>
