Abstract: The present invention demonstrated the potential use of Lactobacillus johnsonii D115 as a probiotic, as a prophylactic agent or as a surface treatment of materials against human and animal pathogens such as Brachyspira pilosicoli, Brachyspira hyodysenteriae, Shigella sonnei, Vibrio cholera, Vibrio parahaemolyticus, Campylobacter jejuni, Streptococcus pneumoniae, Enterococcus faecalis, Enterococcus faecium, Clostridium perfringens, Yersinia enterocolitica, Escherichia coli, Klebbsiella pneumoniae, Staphylococcus aureus, Salmonella spp., Bacillus cereus, Aspergillus niger and Fusarium chlamydosporum. The proteineous antimicrobial compound was partially characterized and found to be heat tolerant up to 121° C. for 15 min, and acid tolerant up to pH1 for 30 min at 40° C. The compound is also stable to enzymatic digestion, being able to retain more than 60% antimicrobial activity when treated with pepsin and trypsin.