Antagonistic activity of butanamine 2,2-dinitro-N-methyl- synthesized by endosymbiotic Bacillus amyloliquefaciens VITAPRJS1 acquired from horse milk.

Endosymbiotic bacteria are known to synthesize bioactive compounds which have biotechnological potentials that enhance immune responses by stimulating the production of immune cells. Horse milk is widely known to have nutraceutical and antimicrobial activities; however, there are no scientific reports on its inhibitory effects. VITAPRJS1, isolated from horse milk, showed non-hemolytic properties and was significantly tolerant to bile salt and NaCl. The isolate also exhibited potent antibacterial activity against pathogenic bacterial strains such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus cereus. The bioactive antibacterial compounds were extracted using dichloromethane and were subsequently purified and identified as butanamine, 2,2-dinitro-N-methyl- through UPLC, GC-MS, and LC-MS analyses. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of functional groups such as alkane, amine, and monosubstituted 1,2-disubstituted. The screened bacterial isolate was identified as Bacillus amyloliquefaciens (OR501558) upon 16S rRNA gene sequencing. To our knowledge, this study represents the first-time report on the presence of Bacillus amyloliquefaciens in horse milk having potent antibacterial activity, highlighting its unexplored potential in biotechnological and pharmaceutical applications.