Protective capacity of bifidobacteria administered as fresh or spray dried cultures against Salmonella Typhimurium.

HRDY, J.; BURNS, P.; ZACARIAS, MF; ZABURLIN, N.; LAVARI, L.; FORZANI, L.; TABACMAN, E.; REINHEIMER, J.; GRANGETTE, C.; VINDEROLA G.

Córdoba

Congreso; V Congreso Internacional de Ciencia y Tecnología de Alimentos (CICYTAC 2014); 2014

Secretaría de Ciencia y Tecnología de Córdoba

Bifidobacteriumanimalis subsp. lactis INL1 is an autochtonous strain isolated from breast milk.B.lactisBb12is one of the commercial strains most used worldwide.The aim of the study was to assess the effect of spray drying on the protective capacity against Salmonella entericaserovarTyphimurium. Male BALB/c mice (6weeks-old) (7-9 animals/group) received (10 days)5x108CFU of the strains as fresh cultures in milk (INL1-F and Bb12-F)or spray dried and reconstituted(INL1-S and Bb12-S), or 20% skim milk (control of infectionIandII).At day 11 animals were challenged with 106 CFU ofSalmonella TyphimuriumMalbrán. By day 6 post-challenge, the surviving animals were sacrificed. The traslocation assay was carried out in blood, liver, spleen, mesenteric lymph nodes and Peyer?s patches. Intestinal content and feces were obtained to determine total and anti-Salmonella secretory gA (ELISA test). Small and large intestines were also obtained in order to determine IFN-γ, TNF and IL-10 (ELISA test). No significant differences were observed in the proportion of dead/total animals for each strain compared to their corresponding control (p=0.053 and p=0.071 for Bb12 and INL1, respectively, Barnard´s test). However, when results were considered grouped by the technology applied, a significant reduction in this proportionwas observed (p=0.008) for animals that received spray-dried cultures(0/15) compared to those that received fresh cultures (5/15) or controls (6/18). No significant differences were observed in the levels of translocation to internal organs.Total S-IgA in feces were higher in the group that received Bb12-S(p=0.011) whereas no differences were observed in the anti-Salmonella S-IgA. Levels of IL-10 were significantly reduced in the small intestine of mice of the Bb12-Sgroup, compared to the control group. No differenceswereobservedforIFN-γand TNF. Due to the reduced simple size, these results must be considered preliminary. However, they suggest that spray drying might be a useful tool to develop dehydrated functional cultures. Results observed may be due to the fact that animals received the same amount of viable cells. However, animals that received spray-dried cultures may have received a higher amount of total cells as spray dry cultures generally contain a small proportion of heat-inactivated cells.