Probiotics are viable nonpathogenic microbes that positively affect host health. Probiotics inhibit infection, activate immunity, and promote mucosal-barrier development. Many microbes have probiotic activity. Nonetheless, the selection of stable strains and their specific mechanism(s) of action are not fully elucidated. Bacteria from ‘Amabere amaruranu’ cultured milk from Kenya were isolated and identified by PCR sequence analysis of the 16S rRNA gene. Isolates were examined for stability to acid and bile, antimicrobial activity, mucin production, and degradation and sensitivity to antibiotics, hence their potential for probiotics. Lactobacillus isolates were acid unstable, bile-stable, nonmucinolytic, and presented antibacterial activity. L. rhamnosus cell fractions increased MUC4 and MUC3 expression in colon cells. Bacillus isolates were acid and bile stable, nonmucinolytic and lacked antimicrobial activity. In conclusion, Lactobacillus isolates that were nonmucinolytic, stable in bile, demonstrated antibacterial activity, sensitive to antibiotics, and stimulated increase MUC4 and MUC3 levels in colon cells could be potential probiotics.

A study was conducted to isolate and identify bacteria from “amabere amaruranu” cultured-milk from Kenya and to evaluate the isolates’ potential to be used as probiotics. Isolates were identified using PCR sequence analysis of the 16S rRNA gene and the API® 50 identification system. Identified isolates included: Acetobacter tropicalis, Bacillus pumilus, Bacillus safensis, Lactobacillus paracasei, Lactobacillus rhamnosus, Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus sciuri. Their potential as probiotics was evaluated using their ability to survive in acid-then-bile conditions, antibacterial activity (against Escherichia coli, Klebsialla pneumonia, Enterococcus faecalis, Pseudomonas aeruginosa and Enterobacter cloacae), mucin degradation activity, and sensitivity to antibiotics (ampicillin, bacitracin, chloramphenicol, erythromycin, kanamycin, penicillin, streptomycin and tetracycline). Lactobacillus isolates were tolerant to acid-then-bile conditions, non-mucinolytic and inhibited growth of indicator strains but only L. rhamnosus was sensitive to all test antibiotics. Bacillus isolates were tolerant to acid-then-bile conditions, non-mucinolytic, lacked antibacterial activity and only B. safensis was sensitive to all test antibiotics. Acetobacter tropicalis isolates were non-mucinolytic but were intolerant to acid-then-bile conditions. In conclusion, both Lactobacillus rhamnosus and Bacillus safensis isolates that showed tolerance to digestive tract conditions, were sensitive to antibiotics and were non-mucinolytic would be recommended for further consideration as candidate probiotics.

A study was conducted to isolate and identify bacteria from “amabere amaruranu” cultured-milk from Kenya and to evaluate the isolates’ potential to be used as probiotics. Isolates were identified using PCR sequence analysis of the 16S rRNA gene and the API® 50 identification system. Identified isolates included: Acetobacter tropicalis, Bacillus pumilus, Bacillus safensis, Lactobacillus paracasei, Lactobacillus rhamnosus, Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus sciuri. Their potential as probiotics was evaluated using their ability to survive in acid-then-bile conditions, antibacterial activity (against Escherichia coli, Klebsialla pneumonia, Enterococcus faecalis, Pseudomonas aeruginosa and Enterobacter cloacae), mucin degradation activity, and sensitivity to antibiotics (ampicillin, bacitracin, chloramphenicol, erythromycin, kanamycin, penicillin, streptomycin and tetracycline). Lactobacillus isolates were tolerant to acid-then-bile conditions, non-mucinolytic and inhibited growth of indicator strains but only L. rhamnosus was sensitive to all test antibiotics. Bacillus isolates were tolerant to acid-then-bile conditions, non-mucinolytic, lacked antibacterial activity and only B. safensis was sensitive to all test antibiotics. Acetobacter tropicalis isolates were non-mucinolytic but were intolerant to acid-then-bile conditions. In conclusion, both Lactobacillus rhamnosus and Bacillus safensis isolates that showed tolerance to digestive tract conditions, were sensitive to antibiotics and were non-mucinolytic would be recommended for further consideration as candidate probiotics.