In vitro Antibacterial Activity of Seribu kuman Leaf (Rhinacanthus nasutus (l.) Kurz) Extracts Against Staphylococcus aureus and Pseudomonas aeruginosa

Abstract

Seribu Kuman leaves (Rhinacanthus nasutus (L.) Kurz) are the herb most commonly used in traditional medicine to treat various diseases. The presence of secondary metabolites, including flavonoids, alkaloids, and phenolics, has led to its known antibacterial activity. This study aims to verify the antibacterial activity of Seribu Kuman leaf extract against Staphylococcus aureus and Pseudomonas aeruginosa. This study involved experimental design using the Kirby-Bauer method, inoculating Mueller-Hilton Agar (MHA) test media containing S. aureus and P. aeroginosa bacteria with Seribu Kuman leaves ethanol extracts at concentrations of 15%, 30%, and 60%. Penicillin and ciprofloxacin were used as positive controls, whereas sterile aquabidest was used as a negative control for the study. The findings of this study showed that Seribu Kuman (R. nasutus) ethanol extract, at a concentration of 60%, presented the most significant inhibition zone against S. aureus, measuring 13.6 mm. In contrast, no inhibition zone was observed for P. aeroginosa. It can be concluded that Seribu Kuman (R. nasutus) ethanol extract can inhibit the growth of S. aureus but not P. aeruginosa. So, Seribu Kuman leaves (R. nasutus) ethanol extract could be an alternative for treating infections caused by S. aureus.