Production and prebiotic activity of exopolysaccharides derived from some probiotics

Abstract

ObjectiveThe aim of this study was to focus on exopolysaccharides (EPSs) produced by Lactobacillus delbrueckii bulgaricus, Lactobacillus helveticus or Lactobacillus casei and their use as a prebiotic for Lactobacillus reuteri, Lactobacillus rhamnosus, Lactobacillus acidophilus or Bifidobacterium bifidum.Materials and methodsOptimization of culture conditions using different carbon and nitrogen sources and different temperature, pH and incubation periods for maximum EPS production was studied.Results and conclusionIt was found that the best conditions were as follows: the use of sucrose (20%) instead of glucose in MRS medium, incubation at pH 7.0 and temperature 37°C for 72 h incubation under anaerobic conditions to give the highest EPS yield; a yield of 13.99 g/l was recorded in case of L. helveticus when grown on the aforementioned optimized conditions. It was found that L. delbrueckii bulgaricus EPS has the highest prebiotic indices (I), varying from 7.9 to 10.1. In contrast, L. helveticus and L. casei EPSs have the lowest prebiotic indices (I), varying from 1.4 to 2.4.