Optimization of Carbon and Nitrogen Source to Enhance Antibacterial Activity from a Sponge-derived Bacillus tequilensis

In our endeavor to find antibacterial from marine bacteria, we screened the microbiota from a Lithistid sponge, collected from Seribu Island, Jakarta. One of the promising strains was K 2.4.2. Identification of the strain using 16S rRNA Sanger sequencing resulted a sequence similarity of 100% to Bacillus tequilensis. Response surface methodology was applied to optimize the culture conditions for enhancing antibacterial activity of the strain. The optimization was carried out using Box-Behnken design experiment to determine the optimum carbon and nitrogen sources in order to produce maximum antibacterial activity. The optimum media with high antibacterial activity was marine broth with the addition of carbon and nitrogen concentration source of sucrose 2.15 % and peptone 1.08%, respectively. In addition, the optimum temperature was 31.18oC. The antibacterial activity response was predicted using a statistical model and compared to the activity in the experiment. The difference between the model and the laboratory experiment was less than 5% which showed a good accuracy. The results of this study once again showed that optimization method effectively reduced time, chemicals, and energy.