The isolation of lactic acid bacteria from human colonic biopsies after enrichment on lactose derivatives and rye arabinoxylo-oligosaccharides Original Research Article

Lactic acid bacteria (LAB) were isolated from human colon biopsies on LAMVAB by enrichment with different substrates such as lactose derivatives, rye arabinoxylo-oligosaccharides and rye fractions. The selected isolates were tested for their ability to adhere to Caco-2 cells. Only Lactobacillus species were enriched under these conditions. From 161 isolates screened, 28% were identified by ribotyping as Lactobacillus rhamnosus, 29% as L. salivarius, 14% as L. cellobiosus, 13% as L. paracasei and the rest remained unidentified.L. rhamnosus was preferentially enriched by lactulose, L. salivarius by lactobionic acid, L. cellobiosus by lactitol and L. paracasei by arabinoxylo-oligosaccharides. The biopsy-derived strains L. rhamnosus E-97948 andL. paracasei E-97949 have potential for further evaluations in their probiotic and technological properties. Lactulose may have prebiotic effects on colonic LAB by favouring their growth.