Aktivitas Antibakteri Ekstrak Daun Bakau Hitam Rhizophora mucronata terhadap Bakteri Penyebab Diare

Abstract

Diarrhea is one of the major health problems in Indonesia. One of the first caused is bacteria. Leaves of Rhizophora mucronata have been widely used by coastal people as folk medicine for treating diarrhea. The aims of this study was to determine the effectivity and inhibitory of Rhizophora mucronata leaf extract as antibacterial to diarrhea-causing bacteria. The procedure of this research used antibacterial assay determined by agar well diffusion method. The activity of each extract was tested by using diarrhea-causing bacteria. Methanol extract of R. mucronata leaf was the highest yield (21.47%). The active compounds of methanol and aqueous extracts consisted of tannin, saponin, flavonoid, phenol hydroquinone, and triterpenoid. Alkaloid was only showed in methanol extract. Methanol extract had the highest antibacterial activity with inhibition zone of 3-12 mm. Minimum inhibitory concentrations of methanol extract were 0.4 mg/mL (Escherichia coli dan Pseudomonas aeruginosa), 0.2 mg/mL (Staphylococcus aureus), and more than 0.4 mg/mL (EPEC dan Salmonella typhimurium). Bioautography of antibacterial activity toward E. coli revealed the active fractions with Rf value of 0.11 and 0.72. Preliminary identification using Dragendorff spray reagent detected the active compound was alkaloid