Publications (48) View all
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Article: Implication of fermentable carbohydrates targeting the gut microbiota on conjugated linoleic acid production in high-fat-fed mice.
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ABSTRACT: In vitro experiments have shown that isolated human gut bacteria are able to metabolise PUFA into conjugated PUFA like conjugated linoleic acids (CLA). The hypothesis of the present paper was that high-fat (HF) diet feeding and supplementation with fermentable carbohydrates that have prebiotic properties modulate the in vivo production of CLA by the mouse gut microbiota. Mice were treated for 4 weeks as follows: control (CT) groups were fed a standard diet; HF groups were fed a HF diet rich in linoleic acid (18 : 2n-6); the third groups were fed with the HF diet supplemented with either inulin-type fructans (HF-ITF) or arabinoxylans (HF-Ax). HF diet feeding increased rumenic acid (cis-9, trans-11-18 : 2 CLA) content both in the caecal and liver tissues compared with the CT groups. ITF supplementation had no major effect compared with the HF diet whereas Ax supplementation increased further rumenic acid (cis-9, trans-11-18 : 2 CLA) in the caecal tissue. These differences between both prebiotics may be linked to the high fat-binding capacity of Ax that provides more substrates for bacterial metabolism and to differential modulation of the gut microbiota (specific increase in Roseburia spp. in HF-Ax v. HF). In conclusion, these experiments supply the proof of concept that the mouse gut microbiota produces CLA in vivo, with consequences on the level of CLA in the caecal and liver tissues. We postulate that the CLA-producing bacteria could be a mediator to consider in the metabolic effects of both HF diet feeding and prebiotic supplementation.The British journal of nutrition 03/2013; · 3.45 Impact Factor -
Article: Integration of Microbial Electrolysis Cells (MECs) in the Biorefinery for Production of Ethanol, H2 and Phenolics
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ABSTRACT: In a biorefinery, biomass is converted into a variety of chemicals, materials and energy. A typical example is the lignocellulosic ethanol biorefinery process, in which substrates such as wheat straw are used as a feedstock for production of ethanol. In this work, an integrated biorefinery procedure is proposed in which the ethanol biorefinery is coupled with a microbial electrolysis cell (MEC), with the aim to further process and valorize the waste stream of bioethanol production. A MEC is an electrochemical system capable of oxidizing reducing equivalents, which results in hydrogen production. The mass and energy balances as well as the economical evaluations, show that this strategy may be useful for additional generation of hydrogen and lignin, thereby increasing the final yield of this biorefinery. From one ton of straw, the yield of ethanol upon yeast fermentation is estimated at 177–190kg, with a hydrogen yield corresponding to 19–23kg H2. The remaining solid residue of 147–160kg comprises primarily lignin. The estimated value of these products approximates the double of that of straw. Integrating a MEC in the biorefinery concept may also be useful for other applications such as polyphenol purification and targeted modification of fruit based phenolics. Examples of such high-value plant polyphenols include equol and resveratrol, which can be produced from soy and grape, respectively. KeywordsLignocellulose-Soy-Grape peels-Phenolics-Energy-Materials-Electrolysis04/2012; 1(1):9-20. -
Chapter: The Gut Microbiota as Target for Innovative Drug Development: Perspectives and a Case Study of Inflammatory Bowel Diseases
12/2011; , ISBN: 978-953-307-257-9 -
Article: Prebiotics to manage the microbial control of energy homeostasis.
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ABSTRACT: The prevalence of obesity is continuously growing and has reached epidemic proportions. It is clear that current methods to combat obesity are not effective enough to reduce the problem. Therefore, further investigation is needed to develop new strategies. Recent research pointed out a potential role of the microbial community associated to the human host in controlling and influencing the energy homeostasis. According to the concept of Gastrointestinal Resource Management, this microbiota and its metabolic potential can be steered with the aim of improving host health. This review therefore focuses on the modulation of the intestinal microbiota through prebiotics with the aim to control several aspects of metabolic homeostasis. In a first part, the importance of host-microbe cross-talk at the intestinal epithelium is discussed. Yet, energy metabolism, which includes both lipid and glucose metabolism, is also regulated by several key organs including the adipose tissue, brain, liver, muscles, pancreas and gut. Therefore, in a second part, we will discuss the microbial factors that are involved in the communication between these different tissues, and their potential management. Finally, we will give some future prospects of the use of prebiotics in an individualised treatment of metabolic disorders.Beneficial microbes. 12/2011; 2(4):305-18. -
Article: Ethylene vinyl acetate as matrix for oral sustained release dosage forms produced via hot-melt extrusion.
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ABSTRACT: Different ethylene vinyl acetate grades (EVA9, EVA15, EVA28 and EVA40 having a VA content of 9%, 15%, 28% and 40%, respectively) were characterized via differential scanning calorimetry. Glass transition temperature (T(g)), polymer crystallinity, melting point and polymer flexibility were positively influenced by the vinyl acetate content. The processability of EVA-based formulations produced by means of hot-melt extrusion (2mm die) was evaluated in function of VA content, extrusion temperature (60-140°C) and metoprolol tartrate (MPT, used as model drug) concentration (10-60%). Matrices containing 50% MPT resulted in smooth-surfaced extrudates, whereas at 60% drug content severe surface defects (shark skinning) were observed. Drug release from EVA/MPT matrices (50/50, w/w) was affected by the EVA grades: 90% after 24h for EVA15 and 28, while EVA9 and EVA40 formulations released 80% and 60%, respectively. Drug release also depended on drug loading and extrusion temperature. For all systems, the total matrix porosity (measured by X-ray tomography) was decreased after dissolution due to elastic rearrangement of the polymer. However, the largest porosity reduction was observed for EVA40 matrices as partial melting of the structure (melt onset temperature: 34.7°C) also contributed (thereby reducing the drug release pathway and yielding the lowest release rate from EVA40 formulations). The Simulator of the Human Intestinal Microbial Ecosystem (SHIME) used to evaluate the stability of EVA during gastrointestinal transit showed that EVA was not modified during GI transit, nor did it affect the GI ecosystem following oral administration.European journal of pharmaceutics and biopharmaceutics: official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V 02/2011; 77(2):297-305. · 3.15 Impact Factor
