INVESTIGADORES
PASTERIS Sergio Enrique
congresos y reuniones científicas
Título:
INHIBITORY ACTIVITY OF Enterococcus faecium FROM FARMED-BULLFROG FOOD AGAINST PATHOGENS RELATED WITH RED LEG SYNDROME AND FOODBORNE BACTERIA
Autor/es:
PASTERIS, S.E.; ROIG BABOT, G.; BUHLER, M.I.; NADER-MACÍAS, M. E.
Lugar:
Nantes
Reunión:
Simposio; FOOD, VETERINARY AND MEDICAL APPLICATIONS OF ANTIMICROBIAL PEPTIDES; 2006
Resumen:
Rana catesbeiana (bullfrog) hatcheries have increased proportionally to the international meat and by-products market (1). The intensive bullfrog litter implicates that the animals are more sensitive to infectious diseases such as red-leg syndrome (RLS), a devastating disease. The main related etiological agents are Proteus vulgaris, Pr. mirabilis, Citrobacter freundii, Pseudomonas aeruginosa and Staphylococcus epidermidis (2). Farmer operations often use antibiotics, while the application of probiotics containing E. faecium strains is being implemented in aquaculture (3). Previously, we studied the microbiota present in a R. catesbeiana hatchery and the beneficial properties of Lactobacillus strains (4,5). In this work we evaluate the antagonist activity of E. faecium strains, isolated from balanced food, against other E. faecium strains, RLS-related pathogens, and Listeria monocytogenes and Salmonella enteritidis as meat spoilage bacteria. Five E. faecium strains isolated during the summer were able to inhibit RLS-associated pathogens by organic acid, mainly Pseudomonas aeruginosa strains. However, E. faecium GST38 inhibited other E. faecium strains by a bacteriocin-like substance, and to L. moncytogenes by H2O2. In the autumn, we isolated eleven E. faecium strains from the same hatchery. Two of them were capable to inhibit all the pathogens assayed and also a Staphylococcus aureus strain. The higher antagonist activity detected was due to organic acids, mainly against meat spoilage bacteria. However, they inhibited pathogens associated with bullfrog hatcheries by producing both, a bacteriocin-like substance and hydrogen peroxide. The results obtained contribute to the study of new probiotic bacteria to be used in R. catesbeiana hatcheries for helping to prevent infectious diseases. References 1- Texeira, R.D., Pereira Mello, S.C.R., Lima dos Santos, C.A.M. 2002. The world market for frog legs. 68, 1-44. FAO / Globefish Research Programme. Rome. 2- Glorioso, J.C., Amborsky, R.L., Amborsky, G.F., Culley, D.D. 1974. Microbiological studies on septicemic bullfrogs (Rana catesbeiana). Am. J. Vet. Res. 35 (8), 1241-1245. 3- Ringø, E., Gatesoupe, F.1998. Lactic acid bacteria in fish. Aquaculture. 160, 177-203. 4- Pasteris, S.E.,  Bühler, M.I., Nader-Macías, M.E. 2004. Evolution and inhibitory properties of lactic acid bacteria isolated from R. toro hatcheries. Biocell. 28 (1), 107.5- Pasteris, S.E., Bühler, M.I., Nader-Macías, M.E. 2006. Microbiological and histological studies in farmed-bullfrog (Rana catesbeiana) displaying red-leg syndrome. Aquaculture. 251,11-18.