Evaluation of resistance to low pH and bile salts of human Lactobacillus spp. isolates

There are nearly 100 trillion bacteria in the intestine that together form the intestinal microbiota. They are 'good' bacteria because they help to maintain a physiological balance and are called probiotics. Probiotics must have some important characteristics: be safe for humans, be resistant to the low pH in the stomach, as well as bile salts and pancreatic juice. Indeed, their survival is the most important factor, so that they can arrive alive in the intestine and are able to form colonies, at least temporarily. The aim of our study was the evaluation of resistance of Lactobacillus isolates from fecal and oral swabs compared to that found in a commercial product. Seven strains were randomly chosen: L. jensenii, L. gasseri, L. salivarius, L. fermentum, L. rhamnosus, L. crispatus, and L. delbrueckii. We observed a large variability in the results: L. gasseri and L. fermentum were the most resistance to low pH, while only L. gasseri showed the best survival rate to bile salts. Interestingly, the commercial product did not show tolerance to both low pH and bile salts

Antioxidant and antimicrobial properties of <i>Casteanea sativa Miller</i> chestnut honey produced on Mount Etna (Sicily)

<p>The aim of this study was the evaluation of antibacterial and antioxidant properties of Monofloral Etna <i>Castanea sativa Miller</i> honeys. <i>Escherichia coli</i> ATCC 25,922<i>, Pseudomonas aeruginosa</i> ATCC 27,853<i>, Enterococcus faecalis</i> ATCC 29,211 and <i>Staphylococcus aureus</i> ATCC 29,213 were investigated for their susceptibilities to two different honeys. Antioxidant activity was evaluated by ORAC, NO scavenger assays, FRAP and DPPH. Antioxidant activity and antibacterial properties were compared with chestnut honeys from different geographical areas and with Manuka honey. UPLC-MS/MS was used for major components characteri sation.</p