Characterization of lactic acid bacteria isolated from the poultry intestinal environment with anti‑Salmonella activity in vitro

HIDALGO, MAXIMILIANO; BABOT, JAIME; FERNÁNDEZ, MA. MAGDALENA; PÉREZ-CHAIA, ADRIANA; AUDISIO, M. CARINA; APELLA, MARÍA CRISTINA

BRAZILIAN JOURNAL OF MICROBIOLOGY

SOC BRASILEIRA MICROBIOLOGIA

Año: 2022

1517-8382

The purpose of this research was the genotypic identifcation of lactic acid bacteria (LAB), isolated from the gastrointestinaltract (GIT) of healthy adult birds, and the study of their safety regarding antibiotic resistance, physiological and functionalproperties involved in the colonization of the GIT of poultry, and Salmonella exclusion, as members of a potential mixed probiotic supplement for poultry. The nucleotidic sequence from Lactobacillus crispatus P1, L. animalis L3, and Enterococcusfaecium CRL 1385 (ex-J96) showed 100, 99.8, and 99.3% identity with L. crispatus DSM 20584 T, Ligilactobacillus salivariusATCC 11741 T, and E. faecium ATCC 19434 T, respectively. These strains showed no resistance to relevant antibiotics usuallyadministered to animals proposed by the European Food Safety Authority. They could endure the detrimental conditions ofthe gastrointestinal tract (pH 2.6 and oxgall 0.1 and 0.4% w/v). In an ex vivo assay, the LAB showed high adherence to thethree sections of the GIT, reaching values higher than 70%. The adhesion to mucus was strain-dependent: L. crispatus CRL1453 evidenced the highest adhesion (>19%) while Lig. salivarius subsp. salivarius CRL 1417 and E. faecium CRL 1385adhered to a lower extent (>9 and 2%, respectively). Moreover, the LAB elicited remarkable anti-Salmonella activity, takinginto account that they could inhibit elevated counts of diferent Salmonella serovars, especially the host-specifc serovars S.Gallinarum and S. Pullorum (up to 8 log CFU/mL decrease in Salmonella counts).