Evaluation of Lactic Acid Bacteria (LAB) against Shigella sonnei ATCC 25931

Abstract

The main functions of Lactic Acid Bacteria (LAB) are the production of organic acids and their characteristic as inhibitors of pathogenic microorganisms. Disease caused by Shigella sonnei is a public health risk factor, as is the resistance they develop to antibiotics. Accordingly, in this study 4 LAB isolated from coffee, quesillo, and breast milk were evaluated under in vitro conditions on Shigella sonnei, considering the presence and cell-free filtration of LAB. The LAB strains were also studied via an antibiotic test using Penicillin, Ceftriaxone, and Ciprofloxacin. The results showed antagonistic activity against Shigella sonnei due to the presence of cells and organic acids. However, the LAB bacteriocins did not inhibit the pathogen. Furthermore, LABs were sensitive to the antibiotics tested. Products from the region such as coffee and quesillo, as well as breast milk are important for their nutritional value and for their LAB content. It would be useful to involve biotechnological research in the coffee and dairy chain on the one hand, and to promote breastfeeding on the other. The tests carried out are qualitative and the inhibitory effect is attributed to the strain and not to a generalization of species. It would also be useful to perform molecular identification of the lactic acid strains studied to introduce them in other food matrices, to evaluate their viability, and to carry out in vivo tests to assess their antimicrobial activity.