Growth behavior of probiotic microorganisms on levan- and inulin-based fructans
Joana Charlot Pohlentz, Nicole Gallala, Konrad Kosciow, Marcel Hövels
Abstract
Modulation of the gut microbiota by prebiotics is an effective tool to improve host health. Here, the prebiotic properties of inulin- and levan-based fructans were investigated using microorganisms obtained from strain collections and isolated from probiotic pharmaceuticals and yogurts. Utilizing the recently characterized endo-levanase LevB2286, levan-fructooligosaccharides (L-FOS) were produced and applied for dedicated growth studies. Real-time growth experiments in 48-well format revealed that 8 out of 17 strains isolated from probiotic products or yogurts responded to prebiotic treatment. Lactobacillus paracasei strains, several bifidobacteria, and a Saccharomyces cerevisiae isolate metabolized supplied fructans efficiently. Overall inulin-FOS were consumed more rapidly than L-FOS. However, this effect may be attributed to the lower average degree of polymerization and the presence of GFn-FOS in the I-FOS preparation used. Growth experiments with fractionated L-FOS provided valuable insights into the influence of the degree of polymerization on fermentability by probiotic bacteria.