Lactobacillus spp de origem humana probióticos potenciais: características funcionais e de segurança

Abstract

The dysbiosis or imbalance of the intestinal tract microbiota becomes an increasingly common problem today, resulting in various related diseases. Bifidobacteria and lactobacilli positively influence the host health, especially due to its ability to inhibit pathogens and stimulate the immune system. The main requirements of a probiotic micro-organism is the ability to resist to digestive juices, adhesion to the intestinal epithelium to exert the activity of pathogen competitive exclusion, besides being safe. Many authors also recommend the use of species-specific probiotic to be most adaptable to the human body and therefore better competitors. This study aimed to characterize some probiotic properties (resistance to gastric and intestinal juices and antimicrobial activity) and safety aspects of probiotics (antimicrobials resistance and hemolytic capacity) of lactobacilli isolated from children infants as compared to commercial probiotic lactobacilli. In inhibition assays, no strain was able to inhibit C. albicans when grown concomitantly. However, the Lac 11 and A1 strains have proven to be as or more efficient than commercial strains to inhibit E. coli. However, the Lac 8 strain showed synergism, stimulating the growth of this bacterium. There was no significant difference in relation to antibiotic resistance between commercial and human origin strains, with the exception of strain 24, which was statistically more sensitive to ampicillin. Regarding the simulation passage through the gastrointestinal (GI) tract, there was no significant difference between the strains. Furthermore, all strains were non-hemolytic.Phenotipic identification by API 50 CHL pointed strains 24, Lac Lac 8 and 11 as belonging to the species L. rhamnosus, the strains A1 and Lac X as L. paracasei. The results indicate the potential of these strains as probiotics