Production, Structural Characterization, and In Vitro Assessment of the Prebiotic Potential of Butyl-Fructooligosaccharides

Abstract

Short-chain fatty acids (SCFAs), especially butyrate, produced in mammalian intestinal tracts via fermentation of dietary fiber, are known biofunctional compounds in humans. However, the variability of fermentable fiber consumed on a daily basis and the diversity of gut microbiota within individuals often limits the production of short-chain fatty acids in the human gut. In this study, we attempted to enhance the butyrate levels in human fecal samples by utilizing butyl-fructooligosaccharides (B-FOS) as a novel prebiotic substance. Two major types of B-FOS (GF3-1B and GF3-2B), composed of short-chain fructooligosaccharides (FOS) bound to one or two butyric groups by ester bonds, were synthesized. Qualitative analysis of these B-FOS using Fourier transform infrared (FT-IR) spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), nuclear magnetic resonance (NMR) and low-resolution fast-atom bombardment mass spectra (LR-FAB-MS), showed that the chemical structure of GF3-1B and GF3-2B were [O-(1-buty-β-D-fru-(2→1)-O-β-D-fru-(2→1)-O-β-D-fru-O-α-D-glu] and [O-(1-buty)-β-D-fru-(2→1)-O-β-D-fru-(2→1)-O-(4-buty)-β-D-fru-O-α-D-glu], respectively. The ratio of these two compounds was approximately 5:3. To verify their biofunctionality as prebiotic oligosaccharides, proliferation and survival patterns of human fecal microbiota were examined in vitro via 16S rRNA metagenomics analysis compared to a positive FOS control and a negative control without a carbon source. B-FOS treatment showed different enrichment patterns on the fecal microbiota community during fermentation, and especially stimulated the growth of major butyrate producing bacterial consortia and modulated specific butyrate producing pathways with significantly enhanced butyrate levels. Furthermore, the relative abundance of Fusobacterium and ammonia production with related metabolic genes were greatly reduced with B-FOS and FOS treatment compared to the control group. These findings indicate that B-FOS differentially promotes butyrate production through the enhancement of butyrate-producing bacteria and their metabolic genes, and can be applied as a novel prebiotic compound in vivo.

Gut Microbiota and Immune System Interactions

“…Given the role of metabolites in autoimmune diseases, one proposed therapeutic strategy is to promote generation of SCFAs in the gut in order to impel the differentiation of naïve CD4+ T-cells into Treg cells, avoiding differentiation into Th1 and Th17 cells. One may support the growth and proliferation of SCFA-producing gut microbes by using appropriate types of dietary fiber [ 143 ], prebiotics such as fructo-oligosaccharides [ 144 , 145 ], or probiotics [ 146 ]. Oral delivery of SCFAs may be problematic as they are metabolized extensively in the upper portions of the intestinal tract [ 147 ].…”

Effects of Selenium- and Zinc-Enriched Lactobacillus plantarum SeZi on Antioxidant Capacities and Gut Microbiome in an ICR Mouse Model

“…The denatured and diluted pooled library and PhiX control (Phix control v3, 30%, v / v ) library were mixed and loaded onto a MiSeq v2 (500 cycle) reagent cartridge (Illumina, San Diego, CA, USA). The primers and methods were as described in our previous study [ 37 ]. After the metagenomic sequencing, paired-end FASTQ files were collected and imported into Quantitative Insights Into Microbial Ecology 2 (QIIME2) (ver.…”

“…2020.6, ) for analysis. Operational taxonomic unit (OTU) taxonomy and related analysis were performed using QIIME2 as described in our previous study [ 37 ]. KEGG associated with selenocompounds metabolism pathways were assessed by conducting phylogenetic investigation of the community by reconstruction of unobserved states (PICRUSt) with the entire picrust2 pipeline command [ 38 ].…”

Butyl-fructooligosaccharides modulate gut microbiota in healthy mice and ameliorate ulcerative colitis in a DSS-induced model

“…The primers and methods were as described in our previous study (Accession Number of NCBI Sequence Read Archive database: SRX13048121). 35 Paired-end FASTQ files from NGS were imported into Quantitative Insights Into Microbial Ecology 2 (QIIME2) (ver. 2019.7, ) for analysis.…”

“…A previously published study 35 showed that butyl-fructooligosaccharides (B-FOSs) are newly synthesized prebiotics composed of short-chain FOS (GF2, 1-kestose; GF3, nystose; GF4, fructofuranosyl-nystose; GF5, 1-F-(1-b- d -fructofuranosyl)-2-nystose) bound with one or two butyric groups by ester bonds. The major B-FOS (GF3-1B) is [ O -(1-buty-β- d -fru-(2 → 1)- O -β- d -fru-(2 → 1)- O -β-D-fru- O -α-D-glu] and a relatively minor structure (GF3-2B) is [ O -(1-buty)-β- d -fru-(2 → 1)- O -β- d -fru-(2 → 1)- O -(4-buty)-β- d -fru- O -α- d -glu].…”