Optimization of Culture Conditions and Batch-Process Control for the Augmented Production of Bacteriocin by Bacillus Species

Abstract

Abstract Background: The rise of antibiotic-resistant microorganisms is a major global health concern. This study explores the potential of soil-derived bacterial isolates in combating such pathogens, focusing on their antimicrobial properties. Results: Fifteen bacterial isolates from agricultural and polluted soils in Jizan and Jeddah were screened for their ability to inhibit common human pathogens. Two Bacillus strains, Bacillus atrophaeus and Bacillus amyloliquaefacins, were identified via 16S rDNA analysis. These strains showed notable antibacterial activity against various pathogens, including Methicillin-Resistant Staphylococcus aureus(MRSA) and Pseudomonas aeruginosa. Optimizing production conditions for their bacteriocin revealed that nutrient and Muller Hinton broths were ideal media, with optimal production observed at 37°C and pH levels of 7 and 8 for Bacillus atrophaeus and Bacillus amyloliquaefacins, respectively. Enhanced production was achieved in a 10-L bioreactor with controlled pH, doubling bacteriocin yield. The study monitored growth, substrate utilization, pH variation, and bacteriocin production over time. Conclusions: The isolated Bacillus strains show promise as sources of potent antimicrobials against antibiotic-resistant bacteria. The optimization of culture conditions significantly boosts bacteriocin production, highlighting the potential of these strains in developing new antimicrobial agents.