GENES RELATED TO BACTERIOCINS PRODUCTION IN POTENTIALLY PROBIOTIC STRAINS ISOLATED FROM CERRADO FRUIT BY-PRODUCTS

Lactic acid bacteria (LAB) are widely recognized for their probiotic potential and ability to synthesize bacteriocins, antimicrobial peptides that contribute to food safety and gut health. This study aimed to investigate the presence of genes associated with bacteriocin production in three LAB strains isolated from by-products of fruits native to the Brazilian Cerrado: Lactiplantibacillus plantarum 9 from bacupari (Salacia crassifolia), Pediococcus acidilactici M7 from mangaba (Hancornia speciosa), and Pediococcus acidilactici P2 from puçá (Mouriri elliptica). The strains were reactivated in MRS broth under anaerobic conditions and incubated at 37 °C for 24 h. DNA extraction for the Whole Genome Sequencing was performed using a modified DNeasy 96 PowerSoil protocol and automated by the QIAcube HT system. Library preparation followed the Illumina DNA Prep protocol, and sequencing was carried out using the Illumina MiSeq platform. Genome assembly was conducted using SPAdes, with quality assessment by QUAST. Species confirmation and contamination analysis were performed using the TYGS platform, and bacteriocin-related genes were identified using the BAGEL4 server. The analysis revealed a sequence with 42.37% similarity to enterolysin A both P. acidilactici M7 and P2. Enterolysin A is known for its broad-spectrum inhibitory activity against Gram-positive bacteria such as Staphylococcus, Listeria, Bacillus, and Enterococcus, functioning through enzymatic degradation of the bacterial cell wall. In L. plantarum 9, gene sequences with 100% similarity to plantaricins A, E, F, J, K, and N were identified. These bacteriocins are widely recognized for their strong antimicrobial action and have applications in food preservation, particularly in dairy, meat, and vegetable products. Plantaricin F has demonstrated efficacy against Staphylococcus aureus, Salmonella typhimurium, and Listeria monocytogenes. The findings support the biotechnological potential of these Cerrado-derived LAB strains as natural biopreservatives and probiotic candidates. However, the direct application of bacteriocins or producer strains in foods must consider possible limitations, such as incompatibility with other fermentative cultures and reduced efficacy against Gram-negative bacteria. To enhance their activity, combined strategies involving cell membrane-disrupting technologies or antimicrobial additives can be employed. Additionally, their use in bioactive packaging presents an innovative solution for improving food quality and safety. These results highlight the relevance of native biodiversity in the development of functional food ingredients.