Ekstraksi dan Bioaktivitas Senyawa Antimikrob dari Bakteri yang Berasosiasi dengan Spons Jaspis sp.

Abstract

Many bacteria associated with sponges produced secondary metabolite or bioactive compounds that has been identified as antimicrobial, anti-cancer, anti-fungi, and anti-bacteria. This study aims to extract antimicrobial compound produced by bacteria associated with sponge Jaspis sp and to test its toxicity toward Artemia salina prawn. Six potential isolates of bacteria isolated from sponge Jaspis sp., coded as SAB E-8, SAB E-33, SAB E-35, SAB E-38, SAB E-40, and SAB S-43, were extracted by using ethyl acetate solvent. Bacterial crude extracts of antimicrobial compounds were tested its activity toward pathogenic and non-pathogenic microbes. The results revealed that the crude extracts of bacteria inhibited the growth of E. coli, B. subtilis, EPEC K1-1, Stapylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida tropicalis. The minimum inhibitory concentration (MIC) from bacterial supernatants range from 12.5% to 100%. Three best isolate i.e. SAB E-35, SAB E-38, and SAB S-43 were fractionated by using thin layer chromatography (TLC). Results of TLC under UV 365 nm and UV 254 nm showed that each extract had active fraction that inhibited P. aeruginsa and EPEC K1-1 through bioautography test. The six bacterial crude extracts were also tested using brine shrimp lethality test (BSLT) with Artemia salina as test organism to find out the toxicity concentration of the extract. Results showed that each extract had different toxicity measured with LC50 provision. SAB E-38 produced the lowest LC50 value which was 81 mg/L.