Survival under stress of halotolerant lactobacilli with probiotic properties

Three halotolerant lactobacilli with probiotic potential previously isolated from Chiapas cheese (Lactobacillus plantarum, L. pentosus and L. acidipiscis) and two commercial lactobacilli with probiotic activity (L. casei Shirota and L. plantarum 299v) were evaluated for their safety and survival capacity under stress. All the strains could grow in optimal conditions up to 6% NaCl and showed sub-lethal growth up to 16% NaCl; all the strains could grow well at pH values between 4.0 and 8.0; with a sub-lethal growth up to pH values of 2.0 and 9.0. L. plantarum 299v could grow up to 2.0% of bile salts, and L. acidipiscis up to 1.5% of bile dried salts. All the strains could be considered safe because all of them were γ-hemolytic and gelatinase negative. Moreover, all the strains showed similar antibiotic resistance pattern and resisted the normal dose used in the food industry of nisin and lysozyme. With these results, it is possible to conclude that the two commercial Lactobacillus strains are halotolerant and that all the strains can be used in a wide range of food products.