Effect of glycation of bovine β-lactoglobulin with galactooligosaccharides on the growth of human faecal bacteria

The in vitro fermentation selectivity of purified galactooligosaccharides (GOS) after their conjugation with bovine β-lactoglobulin (β-LG) via the Maillard reaction and a subsequent simulated gastrointestinal digestion was evaluated. Changes in human faecal bacterial populations, lactic acid and short-chain fatty acids after 10 h and 24 h of fermentation of the digested β-LG:GOS conjugates revealed that this mixture of glycated peptides had a similar bifidogenic activity to the unconjugated GOS. These findings could open up new applications for Maillard reaction products in the functional foods field.The authors gratefully acknowledge financial support from the Spanish Council for Scientific Research (CSIC) (PIF-SIALOBIOTIC 200870F010-1, -2, -5), from the Spanish Ministry of Education and Science (CONSOLIDER INGENIO 2010 Programme; FUN-C-FOOD CSD2007-063) from Junta de Castilla La Mancha and from European regional development fund (ERDF). Oswaldo Hernández- Hernández thanks the CSIC for a JAE-PreDoc PhD-grant.Peer Reviewe

Chito-oligosaccharides (COS) functionality: Antimicrobial activity and antioxidant capacity in vitro

Trabajo presentado al 10th International Conference of the European Chitin Society celebrado en San Petersburgo (Rusia) del 20 al 24 de mayo de 2011.M. Mengíbar wants to thank her FPU grant from Ministry of Innovation and Science (Spain). This research was supported by the Projects MAT2009-058791, MAT2010-21621-C02-01 from Ministry of Innovation and Science (Spain) and S2009/ENE-1660 (Fondos Feder) de la Comunidad Autónoma de Madrid (Spain).Peer Reviewe

Assessment of the in vitro prebiotic potencial of novel oligosaccharides enzymatically synthesized using microbial transglycosidases acting on sucrose

Trabajo presentado al VII Workshop Probióticos, Prebióticos y Salud, celebrado en Sevilla (España) del 28 al 29 de enero de 2016.A wide range of non-digestible oligosaccharides with potential of being selectively fermented in the human gut is emerging, which can be considered as candidate functional food ingredients. Among the strategies used to obtain new prebiotic candidates, enzymatic synthesis has attracted special attention as this process commonly exhibits high yields, substrate specificity and regio- and stereo-specificity. Once the challenges of production, structural characterization and purification have been met, evaluation of the prebiotic potential of dietary carbohydrates is an essential research target. In this work, fermentation profiles of five enzymatically synthesized purified oligosaccharides (4-galactosyl-kojibiose, kojibiose, lactulosucrose, and sets of lactosyl- (DP 4-6) and raffinosyl-oligofructosides (DP 4-7)) were studied using an in vitro batch-culture fermentation system inoculated with human faecal slurries, simulating the events in the distal colon.This work has been financed by project AGL2011-27884 from the Spanish Ministry of Science and Innovation (MICINN). M. Díez-Municio is supported by CSIC through JAE-Pre Programme co-funded by European Social Fund (ESF) and she conducted a predoctoral short-stay at the University of Reading through a CSIC International Programme (project i-LINK+ 2013-0827).Peer Reviewe

Enzymatic synthesis and structural characterization of theanderose through transfructosylation reaction catalyzed by levansucrase from Bacillus subtilis CECT 39

This work addresses the high-yield and fast enzymatic production of theanderose, a naturally occurring carbohydrate, also known as isomaltosucrose, whose chemical structure determined by NMR is α-d-glucopyranosyl-(1 → 6)-α-d-glucopyranosyl-(1 → 2)-ß-d-fructofuranose. The ability of isomaltose to act as an acceptor in the Bacillus subtilis CECT 39 levansucrase-catalyzed transfructosylation reaction to efficiently produce theanderose in the presence of sucrose as a donor is described by using four different sucrose:isomaltose concentration ratios. The maximum theanderose concentration ranged from 122.4 to 130.4 g L-1, was obtained after only 1 h and at a moderate temperature (37 °C), leading to high productivity (109.7-130.4 g L-1h-1) and yield (up to 37.3%) values. The enzymatic synthesis was highly regiospecific, since no other detectable acceptor reaction products were formed. The development of efficient and cost-effective procedures for the biosynthesis of unexplored but appealing oligosaccharides as potential sweeteners, such as theanderose, could help to expand its potential applications which are currently limited by their low availability.This work has been funded by Optibiotix Health plc. L.R-A. thanks the Spanish Research Council (CSIC) and the Spanish Ministry of Economy and Competitiveness for a Juan de la Cierva contract.Peer Reviewe

In vitro fermentation by human gut bacteria and interference in pathogen adhesion of prebiotic carbohydrates glycated with hydrolyzed caseinomacropeptide

Resumen del póster presentado a la International Scientific Conference on Probiotics and Prebiotics celebrada en Kosice (Slovak Republic) del 12 al 14 de junio de 2012.Peer Reviewe

In vitro fermentation by human gut bacteria and interference in pathogen adhesion of prebiotic carbohydrates glycated with hydrolyzed caseinomacropeptide

Resumen del póster presentado a la International Scientific Conference on Probiotics and Prebiotics celebrada en Kosice (Slovak Republic) del 12 al 14 de junio de 2012.[Introduction]: Previous in vitro and in vivo studies have shown that Amadori compounds, first stable products of Maillard reaction (MR), are non-digestible and could reach the colon to be fermented by microorganism. On the other hand, several works have reported the prebiotic properties of galactooligosaccharides (GOS) synthesized from lactase (GOS-La) and lactulose (GOS-Lu). Whilst bovine caseinomacropeptide (CMP) has shown to possess the ability to exert different beneficial biological properties, such as the inhibition of pathogen adhesion. Therefore, the objective of this work was to determine the effects of a fraction rich in Amadori compounds derived from the glycation of hydrolyzed CMP with GOS-La and GOSLu on human intestinal microbiota using small-scale in vitro batch culture and their ability to inhibit in vitro pathogen adhesion to mucin. [Methods]: Glycoconjugates were incubated using fecal samples from 3 human donors under controlled and anaerobic conditions (pH 6.8- 37°C) during 10 and 24 h. Bacterial enumeration was carried out using FISH and lactic acid and SCFA quantiflcation using LC-UV. Adhesion assays were carried out in multi-well plates with immobilized mucin and using Salmonella enterica subsp. enterica scrotype Typhimurium CECT 443 and Listeria monocytogenes CECT 935 labelled with carboxyfluorescein diacetate as indicator strains. Fluorescence of adhered cells was quatified after 1 h of incubation at 37°C at λ 485 nm; λ 538 nm Adhesion was expressed as the percentage of fluorescence recovered after binding to mucin. [Results]: After incubation with human fecal samples, glyeoconjugates exhibited a bifidogenic activity, similar to that observed for the corresponding free prebiotic carbohydrates; however, non-significant differences were found in numbers of Bacteroides, Lactobacillus-Enteroeoccus, C. histolyticum subgroup, Atopobium and C. coccoides group. In general, the concentrations of lactic acid and SCFA produced after fermentation were similar in thc presence of GOS and in their respective glycoconjugates. On the other hand, glycoconjugates signiflcantly reducced the adhesion of S. enterica and L. monocytogenes to mucin as compared with their respective GOS. These results suggested that the use of specific dietary neoglycoproteins can help to interfere with the first interactions between intestinal pathogens and epithelial cells that could lead to infections and excessive inflammation. [Discussion]: The glycation process keeps the prebiotie properties of GOS and the anti-adhesive pathogen propertics to mucin of CMP; in consequence, glycation via MR under controlled conditions could be a new alternative to obtain multi-functional novel ingredients with multiple beneficial effects on human health. These results provide useful information to perform further gut persistence and in vivo studies to explore the potential health benefits of these neoglycoconjugates on animals and human volunteers.Peer Reviewe