Caracterização taxonômica e fisiológica de bactérias ácido-láticas isoladas de pescado marinho

Abstract

Lactic acid bacteria constitute a diversified group associated with the production of food, including fermented fishes. Through fermentative processes, it is possible to obtain several healthy and tasty products. Those bacteria are also important in medicine due to their probiotic activities. In this context, nine lactic acid bacteria were isolated from sardine and leatherjacket fish. Among them, two lineages, and the reference strain Leuconostoc mesenteroides ATCC8293 were physiologically characterized. Lactobacillus homohiochii F3 grew optimally at 40 C, differently from Lactobacillus intestinalis G1 and Leuconostoc mesenteroides ATCC8293 that grew optimally at 30 C. With regard to NaCl tolerance, L. homohiochii F3 and L. mesenteroides ATCC8293 grew in media containing 5% NaCl. Lactobacillus intestinalis G1 grew in media containing 7.5% NaCl and can be considered more halotolerant than the other species. L. mesenteroides ATCC8293 can be considered slightly halophilic. In non-optimal NaCl concentrations, the addition of organic solutes to the culture media was effective in restoring the osmotic balance of the bacteria.