Assessment of Antimicrobial Effect of Soil Bacillus sp. Isolates against Select Pathogenic Bacteria

Abstract

Background: Soil Bacillus sp. provides good resources for the isolation of therapeutically important products that fight against bacteria that cause infections, and a variety of bacteria have acquired antibacterial resistance against commercial antibiotics; therefore, it was necessary to find substances that avoid the formation of resistance against these antibiotics. Examination of the effectiveness of secondary substances produced by Bacillus sp. against Klebsiella pneumoniae, Staphylococcus aureus, Escherichia Coli, Acetobacter aceti, Acetobacter baumannii, and Pseudomonas aeruginosa. Materials and Methods: Bacillus sp. were collected from different sites. After isolation and identification of Bacillus sp. the primary screening was observed against five pathogenic bacteria, then the Bacillus sp. was fermented to observe the secondary metabolite antimicrobial effect on these bacteria. Gas chromatography analysis for secondary metabolites was done to detect the components of this substance. Results: Evidence of antimicrobial effectiveness against E. coli was noted. Absence of antimicrobial effects was detected on other pathogenic bacteria during the initial screening phase. The antibacterial activity of the secondary metabolite was observed against all test pathogens. Notably, Klebsiella pneumoniae, a gram-negative pathogen, was more sensitive than other pathogenic bacteria in this research. Additionally, Staphylococcus aureus, a gram-positive pathogen, was also affected. Conclusion: The secondary metabolites from Bacillus sp. demonstrated potential as effective antibacterial agents against select pathogenic bacteria.