The Effect of Betel Leaf Powder Preparation on the Minimum Inhibitory Concentration (MIC) of Salmonella sp. Growth

Abstract

Background: The high incidence of gastroenteritis and typhoid fever caused by Salmonella in Indonesia is worsened by bacterial resistance to commercial antibiotics. Therefore, herbal plants such as betel leaf preparations need to be investigated as alternative antibacterial agents. Objective: This study aimed to determine the effect of betel leaf (Piper betle L.) powder preparations on the Minimum Inhibitory Concentration (MIC) of Salmonella sp. growth. Research Methods: This was a laboratory experimental study with a post-test only control group design. Betel leaf powder was tested at doses of 0.5–10 mg with three replicates. Inhibitory activity was assessed using the well diffusion method on Mueller Hinton Agar by observing clear zones. Ampicillin served as the positive control and sterile distilled water as the negative control. Differences between doses were analyzed using the Kruskal-Wallis test. Research Results: The ampicillin positive control produced an inhibition zone of 5 mm, whereas the negative control showed dense bacterial growth without a clear zone. Betel leaf powder at doses of 0.5–9.5 mg left the medium turbid, with an inhibition zone of 0 mm. A thin clear ring was visible only at the highest dose of 10 mg, with a mean diameter of 0.1 mm. The Kruskal-Wallis test showed a significant effect of dose (p < 0.05). Conclusion: Betel leaf powder suspended directly in sterile distilled water did not inhibit the growth of Salmonella sp. at low to moderate doses (0.5–9.5 mg). Inhibition appeared only as a very thin zone at 10 mg, so the exact MIC value could not be determined.