Fraksinasi komponen aktif antibakteri ekstrak kulit batang tanaman berenuk (Crescentia cujete L)

Abstract

The objectives of this research are to determine the most antibacterial active fraction of berenuk stem bark extracts, to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and to identify phytochemical constituents of the fraction. Preliminary screening of crude methanol extract and all fractionated extracts (n-hexane, ethyl acetate, and aqueous fraction) against Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative) were tested by disc-diffusion assay. The results showed that only methanol extract and its n-hexane and ethyl acetate fractions that could inhibit growth of all tested bacteria, and the most active fraction among all fractionated extract was n-hexane fraction. Fractionation of n-hexane extract using silica gel column chromatography (gradient elution) produced 10 fractions. All of the fractions showed antibacterial activities, and the most active was fraction II with percentage towards S. aureus was 35.86% and E. coli was 63.01%. The MIC towards S. aureus and E. coli were 0.2 and 0.1 mg/mL, and the MBC for both of bacteria were 10 and 5 mg/mL, respectively. Phytochemical screening showed that steroid and alkaloid were the active constituents of the fraction II. This result concludes that steroids and alkaloids from berenuk stem bark are potential as antibacterial agents.