A prebiotic matrix for encapsulation of probiotics: physicochemical and microbiological study

Abstract

This work aims to develop an encapsulated oral-synbiotic supplement by studying the effect of adding inulin in alginate beads and observing its ability to protect three probiotic strains: Pediocucus acidilactici, Lactobacillus reuteri and Lactobacillus salivarius. Beads of different inulin concentrations 0%, 5%, 10%, 15% and 20% (w/v) in 2% (w/v) alginate solution were prepared by the extrusion/ionotropic gelation method. Polymer distribution within beads was characterised using confocal laser scanning microscopy. Interactions between alginate and inulin were monitored by Fourier transform infra-red spectroscopy (FTIR). Effect of encapsulation on viability, antimicrobial ability, acid tolerance and bile tolerance of probiotic strains were investigated. Antimicrobial and probiotic properties of bacterial strains were not affected by encapsulation. Bacterial protection against acidity was increased by adding inulin. Beads with 5% w/v inulin were the most effective in bacterial protection against bile-salts. To our knowledge, this work is the first to use such high concentrations of inulin.

Keywords:

• Inulin-Alginate beads
• prebiotics
• probiotics: Lactobacillus reuteri ATCC 53608
• Lactobacillus salivarius
• Pediococcus acidilactici Ul5

Acknowledgements

The authors would like to thank Mr. Pascal Dubé, Ms. Diane Gagnon (Institute of nutraceuticals and functional foods, Laval University, Quebec, QC, Canada) Mr. Richard Janvier (Molecular Imaging and Microscopy Platform, Laval University, Quebec, QC, Canada) and Ms Caroline Vachias (GReD, Université de Clermont-Ferrand, France).

Declaration of interest

The authors report no declarations of interest.