Growth behavior of probiotic microorganisms on levan- and inulin-based fructans

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.

Keywords

• Fructooligosaccharides
• Levan
• Inulin
• Prebiotics
• Probiotics