The Administration Matrix Modifies the Beneficial Properties of a Probiotic Mix of Bifidobacterium animalis subsp. lactis BB-12 and Lactobacillus acidophilus LA-5.

Consumption of dairy products is one of the most natural ways to introduce probiotics. However, the beneficial effects of the probiotics might depend on the administration form. The aim of this study was to investigate the beneficial properties of two probiotic strains: Bifidobacterium animalis subsp. lactis (BB-12) and Lactobacillus acidophilus (LA-5) in different administration forms (capsules and yogurt). First, in vitro resistance to gastrointestinal condition, surface properties, and immunomodulation capacities were determined. Then, the anti-inflammatory properties of the probiotic strains administrated on yogurt or capsules were tested in a dinitrobenzene sulfonic acid (DNBS)-induced colitis mouse model. The survival rates of BB-12 and LA-5 strains to gastrointestinal conditions were slightly higher when yogurt was used as carrier. They showed most affinity to hexane (no-polar basic solvent) than ethyl-acetate (polar basic solvent). BB-12 showed the higher binding capacity to HT-29, Caco-2, and mucin. Both probiotic candidates suppress the secretion of IL-8 secretion by HT-29-TNF-α stimulated cells. Finally, administration of BB-12 and LA-5 strains improve colitis in mice. They protect against weight loss, inflammation, and hyperpermeability induced by DNBS. However, these anti-inflammatory effects were limited when mice were treated with the probiotic strain on a yogurt matrix. Overall results indicate that BB-12 and LA-5 positive properties are compromised depending on the matrix. Consequently, the selection of an appropriate matrix is an important criterion to conserve the positive benefits of these probiotic strains.

Physiological Effects of Whey- and Milk-Based Probiotic Yogurt in Rats.

In an in vitro experiment commercially available probiotic products were tested for the survival of bacteria under conditions of simulated human digestion either when used alone or mixed into yogurt. In the in vivo experiment the effects of feeding a whey- and milk-based yogurt prepared with the probiotic strain showing adequate survival in the in vitro experiment, was measured on body weight, feed con¬sumption and immune response of rats (IgG and IgA level after immunisation), on the composition and volatile fatty acid production of the intestinal microbiota and on the structure of intestinal villi. The Lactobacillus acidophilus (LA-15) strain had inadequate surviving ability in rats. Bifidobacterium animalis ssp. lactis (BB-12) improved the composition of the intestinal microflora, whereas whey-containing product had a mild immunostimulating effect and exerted a favourable influence on the morphology of intestinal villi. The consumption of yogurts increased the depth of crypts in the ileum, which resulted in enhanced secretion and thus softer faeces.