Cultured milk bacterial isolates survive well in digestive tract conditions and could be potential probiotic candidates (1118.4)

Abstract

Probiotics are viable non‐pathogenic microbes that positively affect host health. Our goal is to understand the influence of probiotics on the intestinal barrier function. In this study bacterial isolates from traditional cultured milk from Kenya were screened for their ability to withstand digestive tract conditions and thence their potential as probiotic candidates. Bacteria in the sample were isolated and identified by single colony PCR sequence match analysis of the 16s rRNA gene. Identified isolates included Lactobacillus spp (6 isolates), Acetobacter spp (2 isolates), Bacillus spp (2 isolates) and 1 Staphylococcus sp. Isolates were examined for acid stability over a 3‐h period, acid and/or bile stability over a 9‐h period, antimicrobial activity, and antibiotic sensitivity to ampicillin, bacitracin, chloramphenicol, erythromycin, kanamycin, penicillin, streptomycin and tetracycline. Two Lactobacillus spp isolates were stable in acid and/or bile, showed antimicrobial activity against K. pneumonia and P. aeruginosa and were sensitive to erythromycin, kanamycin, streptomycin and tetracycline. The remaining 4 Lactobacillus isolates were unstable in acid and/or bile, showed antimicrobial activity against K. pneumonia and P. aeruginosa and were sensitive to all tested antibiotics. The Bacillus spp isolates were acid and/or bile stable, showed no antimicrobial activity, and were susceptible to all the tested antibiotics. The Staphylococcus sp and 2 Acetobacter spp were acid and bile unstable and did not have antimicrobial activity and were sensitive to the antibiotics tested. In conclusion, the Lactobacillus isolates that showed stability in acid/bile conditions, demonstrated antimicrobial activity and were sensitive to antibiotics could be potential probiotic candidates.Grant Funding Source: East Tennessee State University Research Development Committee Small Grants Program