The Effect of Selected Synbiotics on Microbial Composition and Short-Chain Fatty Acid Production in a Model System of the Human Colon

Abstract

BackgroundPrebiotics, probiotics and synbiotics can be used to modulate both the composition and activity of the gut microbiota and thereby potentially affecting host health beneficially. The aim of this study was to investigate the effects of eight synbiotic combinations on the composition and activity of human fecal microbiota using a four-stage semicontinuous model system of the human colon.Methods and FindingsCarbohydrates were selected by their ability to enhance growth of the probiotic bacteria Lactobacillus acidophilus NCFM (NCFM) and Bifidobacterium animalis subsp. lactis Bl-04 (Bl-04) under laboratory conditions. The most effective carbohydrates for each probiotic were further investigated, using the colonic model, for the ability to support growth of the probiotic bacteria, influence the composition of the microbiota and stimulate formation of short-chain fatty acids (SCFA).The following combinations were studied: NCFM with isomaltulose, cellobiose, raffinose and an oat β-glucan hydrolysate (OBGH) and Bl-04 with melibiose, xylobiose, raffinose and maltotriose. All carbohydrates showed capable of increasing levels of NCFM and Bl-04 during fermentations in the colonic model by 103–104 fold and 10–102 fold, respectively. Also the synbiotic combinations decreased the modified ratio of Bacteroidetes/Firmicutes (calculated using qPCR results for Bacteroides-Prevotella-Porphyromonas group, Clostridium perfringens cluster I, Clostridium coccoides - Eubacterium rectale group and Clostridial cluster XIV) as well as significantly increasing SCFA levels, especially acetic and butyric acid, by three to eight fold, as compared to the controls. The decreases in the modified ratio of Bacteroidetes/Firmicutes were found to be correlated to increases in acetic and butyric acid (p = 0.04 and p = 0.03, respectively).ConclusionsThe results of this study show that all synbiotic combinations investigated are able to shift the predominant bacteria and the production of SCFA of fecal microbiota in a model system of the human colon, thereby potentially being able to manipulate the microbiota in a way connected to human health.

Metabolism of Four α-Glycosidic Linkage-Containing Oligosaccharides by Bifidobacterium breve UCC2003

“…Such pathways may reflect common elements in the diets of the hosts of such bacteria, while it may also allow certain species/strains the capacity to effectively colonize the gut or reach higher numbers when the host's diet contains more specialized carbohydrates. In a recent study (88), levels of B. animalis subsp. lactis Bl-04 were shown to be selectively increased 10-to 100-fold on melibiose, xylobiose, raffinose, and maltotriose in a model system of the human colon, indicating that these carbohydrates have the potential to serve as prebiotics.…”

An ATP Binding Cassette Transporter Mediates the Uptake of α-(1,6)-Linked Dietary Oligosaccharides in Bifidobacterium and Correlates with Competitive Growth on These Substrates

“…Growth of B. animalis subsp. lactis Bl-04 on the tetrasaccharide (stachyose) and pentasaccharide (verbascose) has been demonstrated (37), which proves that these ligands are indeed taken up albeit with lower selectivity than raffinose the preferred ligand. The preference for trisaccharides was also confirmed by monitoring the depletion of melibiose, raffinose, and stachyose during growth of B. animalis subsp.…”

Lactobacillus reuteri-Specific Immunoregulatory Gene rsiR Modulates Histamine Production and Immunomodulation by Lactobacillus reuteri

“…Several probiotic species convert dietary components into bioactive molecules that affect the host's physiological functions. Many probiotics produce short-chain fatty acids (SCFAs) as a product of dietary fiber catabolism (6). SCFAs have anti-inflammatory effects on human immune cells and the gut through binding with G-protein-coupled receptor 43 (GPR43), and this interaction plays a key role in the resolution of several inflammatory conditions, such as arthritis, colitis, and asthma (7).…”