Aktivitas Senyawa Antimikroba Bacillus sp. terhadap Biofilm Bakteri Patogen Oportunis Asal Tambak Udang Intensif

Abstract

Salmonella sp., Staphylococcus aureus, and Escherechia coli are opportunistic pathogenic bacteria found in shrimp ponds and able to form biofilm on solid surfaces. The purpose of this study was to determine the ability of antimicrobial compounds produced by Bacillus sp. in inhibiting the growth of opportunistic pathogenic bacterial biofilms. Opportunistic pathogens bacteria were isolated from water, sediment and from solid surface using cotton swab of intensive shrimp ponds in several location in North Sumatera Province. Opportunistic pathogenic bacteria were antagonist tested against isolates of Bacillus sp. B1, B4, B9, B11, and B12, to see the ability of inhibition of Bacillus sp. Isolate of Bacillus sp. B9 were able to inhibit 3 types of pathogen bacteria, while B12 only able to inhibit two types of pathogenic bacteria, except Escherechia coli. Opportunistic pathogenic bacterial biofilm was form using stainless steel as an attachment surfaces, incubated for 1, 3, and 6 days, then immersed in 10 ml of antimicrobial crude extract and the number of bacteria viability were counted. Biofilm cells increased with time of incubation, except for Escherechia coli that decreased on the 6th day of incubation. The crude extract of antimicrobial compounds of Bacillus sp. B9 and B12 isolates were able to reduce the opportunistic pathogen bacteria biofilm up to 102 -103 CFU/ml within 24 hours.