Characterization of Bacteriocin Produced by Bacillus subtilis 11A Isolated from the Gastrointestinal Tract of Indonesian Native Chicken (Gallus domesticus)

The purpose of this study was to characterize bacteriocins produced by Bacillus subtilis 11A isolated from Indonesian native chicken’s ileum . Characterization of bacteriocins included antimicrobial activity, the stability to temperature, pH, and storage time. Antimicrobial activity was tested against Escherichia coli FNCC 0091 , Salmonella typhimurium FNCC 0134, and Staphylococcus aureus FNCC 0143. Stability to temperature was tested to 4, 30, 70, 80, 90, 100 o C for an hour and 121 o C for 15 min. Stability to pH was tested to pH 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 for an hour. Stability to storage was tested for 7, 14, 21, and 28 days at refrigerator (4 o C) and room temperature (30 o C). The result showed that bacteriocins produced by Bacillus subtilis 11A were more effective against pathogens Gram-negative ( Escherichia coli and Salmonella typhimurium ) than Gram-positive ( Staphylococcus aureus ) (P<0.05). The bacteriocins produced by Bacillus subtilis 11A were heat until 90 o C, stable at pH 6–10 and stored at refrigerator up to 28 days (P<0.05). This study suggested that this bacteriocins might become potential candidate for use as biodegradable natural fed and alternative antimicrobial agents to solve the increasing trends of problems of antibiotic resistance