SCREENING, EXTRACTION, AND PARTIAL PURIFICATION OF ANTIMICROBIAL COMPOUNDS AGAINST PATHOGENS FROM INDONESIAN MANGROVE SEDIMENTS

Antibiotics are organic compounds that are produced by microorganism or synthetic and semisynthetic compounds that have the ability to kill or inhibit growth of other microorganism. Nowadays, most microorganisms become resistant to at least one antibiotic. Those resistances can be caused by inappropriate use of antibiotics. Therefore, there is a need to find a novel antibiotic to solve the resistance. This research was conducted to screen antimicrobial compounds from Indonesian mangrove sediments, extract the antimicrobial compounds, and to partially purify these substances. This study used 140 marine bacteria isolates from 7 different mangrove sediments. Based on preliminary screening, only twelve isolates showed antimicrobial activity against Bacillus cereus, Staphylococcus haemolyticus, and Streptococcus pneumoniae. These samples were extracted with several organic compounds, which are chloroform, n-hexane, dichloromethane, toluene, and 1-butanol. The best solvent for extraction could not be determined, because it depends on the sample. After extraction, the crude extract was tested with antimicrobial assays. Thin layer chromatography was used to partially purify the antimicrobial compounds. Components of antimicrobial compounds in the samples were successfully separated into two spots using 1-butanol:acetic acid:water (4:1:2) with different retention factor values. On TLC separation method, the best mobile phase combination for separating the antimicrobial compounds was 1-butanol:acetic acid:water (4:1:2). This mobile phase combination could be used to separate the antimicrobial compounds into two spots.