Isomer-Specific Consumption of Galactooligosaccharides by Bifidobacterial Species

Abstract

Prebiotics are non-digestible substrates that stimulate the growth of beneficial microbes in the human intestine. Galactooligosaccharides (GOS) are food ingredients that possess prebiotic properties, in particular, promoting the growth of bifidobacteria in situ. However precise mechanistic details of GOS consumption by bifidobacteria remains poorly understood. Because GOS are mixtures of polymers of different lengths and linkages, there is interest to determine which specific structures provide prebiotic effects in order to potentially create better supplements. We here present a method comprising porous graphitic carbon separation, isotopic labeling and mass spectrometry analysis for the structure specific analysis of GOS isomers and their bacterial consumption rate. Using this strategy, the differential bacterial consumption of GOS by the bifidobacteria species B. longum subsp. infantis, B. animalis subsp. lactis and B. adolescentis was determined, indicating that the use of specific GOS isomers in infant formula may provide enrichment of distinct species.

Prebiotic galactooligosaccharides activate mucin and pectic galactan utilization pathways in the human gut symbiont Bacteroides thetaiotaomicron

“…Previous studies on GOS consumption by Bifidobacterium strains showed that each strain consumed GOS at different rates and growth rate was directly attributed to the ability of the Bifidobacterium species to use specific isomers within the GOS mixtures40. Our study shows that B. thetaiotaomicron uses almost all isomers in the GOS mixture.…”

A β1‐6/β1‐3 galactosidase from Bifidobacterium animalis subsp. lactis Bl‐04 gives insight into sub‐specificities of β‐galactoside catabolism within Bifidobacterium

“…maturation of the immune system, pathogen exclusion, and regulation of mood and behaviour (Nicholson et al ., ). The preferential metabolism of short β‐galactosides of different origin by bifidobacteria is well established (Davis et al ., ; Peacock et al ., ). By contrast, the molecular recognition and specificity determinants of β‐galactosidases in Bifidobacterium and other gut microbiota members, remain elusive.…”

“…lactis shows a different isomer‐specific utilization pattern of commercial β‐galacto‐oligosaccharides as compared to B. longum subsp. infantis and B. adolescentis (Peacock et al ., ), which are persistent members of human infant and adult gut microbiota respectively. Thus, B. animalis subsp.…”

Prevention of Necrotizing Enterocolitis Through Manipulation of the Intestinal Microbiota of the Premature Infant

“…The most commonly administered prebiotics include lactulose, inulin, polydextrose, short-chain (sc) and long-chain (lc) fructo-oligosaccharides and galacto-oligosaccharides, and combinations of the above. The potential complexity of the prebiotic approach to altering the gut microbiota is exemplified by the observations that different isomers of GOS are preferentially consumed by different species of Bifidobacterium 112 and that some gut pathogens (e.g. E coli EHEC and C. perfringens ) are able to consume some isomers of GOS 113 .…”