In this paper, the Dynamic Gastrointestinal Simulator (simgi®) is used as a model to the study the metabolic activity of probiotics at the intestinal level, and in particular, to assess the impact of probiotic supplementation in the microbial metabolism of grape polyphenols. Two independent simulations using fecal samples from two healthy volunteers were carried out. Changes in microbiota composition and in metabolic activity were assessed by qPCR and 16S rRNA gene sequencing and by analyses of phenolic metabolites and ammonium ions (NH).
View Article and Find Full Text PDFThe increasing use of silver nanoparticles (AgNPs) in consumer products has led to concern about their impact on human health. This paper aims to provide new scientific evidence about the modifications and potential effects of AgNPs with food applications during their passage through the digestive tract. For that, two types of AgNPs [solid polyethylene glycol-stabilised silver nanoparticles (PEG-AgNPs 20) and liquid glutathione-stabilised silver nanoparticles (GSH-AgNPs)] were initially subjected to gut-microbial digestion simulation in an in vitro static model.
View Article and Find Full Text PDFThe aim of this work was to evaluate the biological activity of four grape pomace (GP) extracts that are rich in polyphenols using as an in vivo model. Different concentrations of the GP extracts were assessed for their effects on the resistance of against thermally induced oxidative stress, accumulation of reactive oxygen species (ROS), and lifespan. The cultivation of with relatively low concentrations of GP extracts increased their resistance against thermal stress and prolonged their lifespan, while high levels displayed detrimental effects.
View Article and Find Full Text PDFThe behaviour of citrus pectin during digestion and its potential prebiotic properties were examined using a Dynamic Gastrointestinal Simulator (simgi®) model for the human gut, which simulates processes in the stomach, small intestine, ascending, transverse and descending colon. A remarkable non-digestibility of pectin in the upper gastrointestinal tract was observed by HPLC-ELSD analysis, where ∼88% of citrus pectin remained intact during its transit through the stomach and small intestine. Fermentation of pectin stimulated the growth of beneficial bacteria such as Bifidobacterium spp, Bacteroides spp and Faecalobacterium prausnitzii.
View Article and Find Full Text PDFThe human gastrointestinal tract harbours the most complex and abundant community of the human body, the colon being where the highest microbial concentration is found (1012 cell/g). The intestinal microbiota exerts metabolic, trophic and protective functions which are important in the maintenance of the host health. Over recent decades, numerous studies have attempted to provide scientific evidence about the environmental factors that can impact on human health through the modulation of the intestinal microbiota composition.
View Article and Find Full Text PDFOver the last few decades, polyphenols, and flavonoids in particular, have attracted the interest of researchers, as they have been associated with the health-promoting effects derived from diets rich in vegetables and fruits, including moderate wine consumption. Recent scientific evidence suggests that wine polyphenols exert their effects through interactions with the gut microbiota, as they seem to modulate microbiota and, at the same time, are metabolized by intestinal bacteria into specific bioavailable metabolites. Microbial metabolites are better absorbed than their precursors and may be responsible for positive health activities in the digestive system (local effects) and, after being absorbed, in tissues and organs (systemic effects).
View Article and Find Full Text PDFBackground: Currently, there is growing interest in extracts derived from winery by-products because of their beneficial health properties, which are associated with the presence of bioactive compounds. In this paper, we have carried out the chemical characterization and in vitro colonic fermentation of four grape pomace (GP) extracts rich in polyphenols and dietary fibre.
Result: Firstly, phenolic and dietary fibre composition of the GP extracts was determined.
The recovery of by-products from agri-food industry is currently one of the major challenges of biotechnology. Castilla-La Mancha produces around three million tons of waste coming from olive oil and wine industries, both of which have a pivotal role in the economy of this region. For this reason, this study reports on the exploitation of grape skins and olive pomaces for the production of lignocellulosic enzymes, which are able to deconstruct the agroindustrial waste and, therefore, reuse them in future industrial processes.
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