In vitro Fermentability of Prebiotic Oligosaccharides by Lactobacilli

Twelve strains of lactobacilli were tested for their growth and ability to utilise six prebiotics (pure substances and commercially available prebiotics) as a sole carbon source. All strains showed a considerable growth on all prebiotics tested. Inulin was the best carbohydrate source for lactobacilli, followed by lactulose and raffinose. A massive increase of viable cells on commercial prebiotic mixtures (Vivinal, Oligomate 55, and Orafti P95) was also observed. Lysozyme susceptibility was assayed in 13 strains of lactobacilli. Eight out of 13 strains were completely resistant to the lysozyme concentration of 400 μg/ml, in the rest of the strains a slight delay of the exponential phase of the growth curves was observed. Lactobacilli tolerated lysozyme well and were able to utilise all prebiotics.