Phyllospheric Brevibacillus parabrevis from Wadi Degla reserve: Isolation, molecular identification, GC-MS profiling, and evaluation of antibacterial, antioxidant, and docking studies

Phyllospheric bacteria are emerging as a promising source of bioactive compounds with antimicrobial and antioxidant properties. These microorganisms, inhabiting the aerial surfaces of plants, have demonstrated significant potential for biotechnological applications. Microbial-derived bioactive compounds have gained significant attention for their potential in developing novel antimicrobial and antioxidant agents. This study investigated the bioactive potential of Brevibacillus parabrevis AUMC-B1, a bacterium isolated from the phyllosphere of Hyoscyamus desertorum in Wadi Degla Reserve. The bacterium was identified through phenotypic and genotypic characterization, and its ethyl acetate extract exhibited significant antibacterial activity, with the highest inhibition observed at 0.8% against Escherichia coli and Staphylococcus aureus. In addition, the strong antioxidant potential was assessed using the DPPH radical scavenging assay. GC-MS analysis identified key bioactive metabolites, including cis-13-eicosenoic acid and 12-methyl-E,E-2,13-octadecadien-1-ol, which were further evaluated through molecular docking. Moreover,docking studies revealed strong interactions with bacterial DNA gyrase, suggesting antibacterial mechanisms, while ADME analysis confirmed favorable pharmacokinetic properties such as high oral absorption and lipophilicity. Gene interaction analysis highlighted the compounds’ potential role in modulating antioxidant pathways. These findings indicate that B. parabrevis AUMC-B1 and its bioactive metabolites have promising antibacterial and antioxidant applications, offering potential for novel therapeutic development.