Probiotic biofilm on carrier surface: A novel promising application for food industry

In this essay work, the ability of probiotic biofilm formation on carrier surface was demonstrated. Probiotic biofilms exhibit the same properties as pathogen microbial biofilms but with higher resistance to low pH values and bile salts. The ability of different probiotic strains (Lactobacillus acidophilus, Bifidobacterium breve, Bifidobacterium longum) to interact with pre-selected carriers divided into 3 categories (polymers, complex food matrices, and inorganic compounds) was tested. Lactobacillus acidophilus and Bifidobacterium longum combined with inorganic silica carrier exhibited the interaction leading to biofilm formation only. Prepared biofilm (Lactobacillus acidophilus) was then subjected to comparative study with planktonic bacterial culture. The ability to survive in the presence of low pH value (pH 1–3) and bile salts (0.3% solution) was evaluated. Low pH value (pH 1) had a harsh effect on free cell culture causing decreased cell viability (71.9±3.2% of viable cells). Biofilm culture exhibited higher resistance to low pH value, the viability exceeded 90%. The exposure of free cell probiotic culture to porcine bile resulted in an almost constant decrease in viability during the study period (68.2±1.1% of viable cells, after 240 min incubation). Viability of biofilm after the exposition to bile was almost constant with a slight decrease of no more than 5% during the study