Search results for "Acetates"
showing 10 items of 94 documents
Analysis of propionate‐degrading consortia from agricultural biogas plants
2016
Abstract In order to investigate the propionate‐degrading community of agricultural biogas plants, four propionate‐degrading consortia (Ap1a, N12, G12, and Wp2a) were established from different biogas plants which were fed with renewable resources. The consortia were cultivated in a batch for a period of 2–4 years and then analyzed in an 8‐week batch experiment for microbial succession during propionate degradation. Community shifts showed considerable propagation of Syntrophobacter sulfatireducens, Cryptanaerobacter sp./Pelotomaculum sp., and “Candidatus Cloacamonas sp.” in the course of decreasing propionate concentration. Methanogenic species belonged mainly to the genera Methanosarcina,…
Human milk and mucosa-associated disaccharides impact on cultured infant fecal microbiota
2020
Human milk oligosaccharides (HMOs) are a mixture of structurally diverse carbohydrates that contribute to shape a healthy gut microbiota composition. The great diversity of the HMOs structures does not allow the attribution of specific prebiotic characteristics to single milk oligosaccharides. We analyze here the utilization of four disaccharides, lacto-N-biose (LNB), galacto-N-biose (GNB), fucosyl-α1,3-GlcNAc (3FN) and fucosyl-α1,6-GlcNAc (6FN), that form part of HMOs and glycoprotein structures, by the infant fecal microbiota. LNB significantly increased the total levels of bifidobacteria and the species Bifidobacterium breve and Bifidobacterium bifidum. The Lactobacillus genus levels wer…
Infant gut microbiota modulation by human milk disaccharides in humanized microbiome mice
2021
Human milk glycans present a unique diversity of structures that suggest different mechanisms by which they may affect the infant microbiome development. A humanized mouse model generated by infant fecal transplantation was utilized here to evaluate the impact of fucosyl-α1,3-GlcNAc (3FN), fucosyl-α1,6-GlcNAc, lacto-N-biose (LNB) and galacto-N-biose on the fecal microbiota and host–microbiota interactions. 16S rRNA amplicon sequencing showed that certain bacterial genera significantly increased (Ruminococcus and Oscillospira) or decreased (Eubacterium and Clostridium) in all disaccharide-supplemented groups. Interestingly, cluster analysis differentiates the consumption of fucosyl-oligosacc…
Considering syntrophic acetate oxidation and ionic strength improves the performance of models for food waste anaerobic digestion.
2021
Current mechanistic anaerobic digestion (AD) models cannot accurately represent the underlying processes occurring during food waste (FW) AD. This work presents an update of the Anaerobic Digestion Model no. 1 (ADM1) to provide accurate estimations of free ammonia concentrations and related inhibition thresholds, and model syntrophic acetate oxidation as acetate-consuming pathway. A modified Davies equation predicted NH3 concentrations and pH more accurately, and better estimated associated inhibitory limits. Sensitivity analysis results showed the importance of accurate disintegration kinetics and volumetric mass transfer coefficients, as well as volatile fatty acids (VFAs) and hydrogen up…
Isocratic high-performance liquid chromatographic determination of tryptophan in infant formulas.
1996
The application to infant formulas of a method for tryptophan determination by isocratic HPLC with UV detection at 254 nm, after derivatization with phenyl isothiocyanate, was studied. Protein was hydrolysed by barium hydroxide at 120 degrees C for 8 h, followed by derivatization with phenyl isothiocyanate, HPLC and UV detection at 254 nm. The optimum chromatographic conditions (pH, ionic strength of elution solvent and eluent ratio) were established. The analytical parameters (linearity, precision, accuracy of derivatization and limits of detection and quantification) were determined. The values obtained demonstrated that the method is useful for determining the tryptophan content of infan…
Detection of an O-methyltransferase synthesising acetosyringone in methyl jasmonate-treated tobacco cell-suspensions cultures.
2013
Acetosyringone (3',5'-dimethoxy-4'-hydroxyacetophenone) is a well-known and very effective inducer of the virulence genes of Agrobacterium tumefaciens but the precise pathway of its biosynthesis in plants is still unknown. We have used two tobacco cell lines, cultured in suspension and exhibiting different patterns of accumulation of acetosyringone in their culture medium upon treatment with methyl jasmonate, to study different steps of acetosyringone biosynthesis. In the two cell lines studied, treatment with 100 mu M methyl jasmonate triggered a rapid and transient increase in acetovanillone synthase activity followed by a progressive increase in S-adenosyl-L-methionine: 5-hydroxyacetovan…
Randomised controlled trial of montelukast plus inhaled budesonide versus double dose inhaled budesonide in adult patients with asthma
2003
Background: Inhaled corticosteroids (ICS) affect many inflammatory pathways in asthma but have little impact on cysteinyl leukotrienes. This may partly explain persistent airway inflammation during chronic ICS treatment and failure to achieve adequate asthma control in some patients. This double blind, randomised, parallel group, non-inferiority, multicentre 16 week study compared the clinical benefits of adding montelukast to budesonide with doubling the budesonide dose in adults with asthma. Methods: After a 1 month single blind run in period, patients inadequately controlled on inhaled budesonide (800 µg/day) were randomised to receive montelukast 10 mg + inhaled budesonide 800 µg/day (n…
Efficacy of leukotriene receptor antagonist in chronic urticaria. A double-blind, placebo-controlled comparison of treatment with montelukast and cet…
2001
Background The cause and pathogenesis of chronic urticaria are still poorly understood. IgE-independent reactions, are common in adult patients with chronic urticaria, who have daily spontaneous occurrence of weals. H1-receptor antagonists (antihistamines) are the major class of therapeutic agents used in the management of urticaria and angioedema. Nevertheless, chronic urticaria is often difficult to treat and may not be controlled by antihistamines alone. It has been postulated that mediators other than histamine, such as kinins, prostaglandin and leukotrienes, may be responsible for some of the symptoms in urticaria which are not controlled by antihistamines. In this study, which was ran…
Randomized placebo-controlled trial comparing desloratadine and montelukast in monotherapy and desloratadine plus montelukast in combined therapy for…
2004
BACKGROUND: H 1 -receptor antagonists are considered to be particularly effective in reducing pruritus, and they are therefore recommended as first-line treatment in patients with chronic idiopathic urticaria (CIU). Recently, antileukotriene receptors have been used in patients with CIU, either administered as monotherapy or combined with H 1 -receptor antagonists. OBJECTIVE: We compared the clinical efficacy of 5 mg of desloratadine administered once daily either as monotherapy or combined with a leukotriene antagonist, 10 mg of montelukast daily, and 10 mg of montelukast administered daily as monotherapy for the treatment of patients affected by CIU with placebo. METHODS: One hundred sixt…
Effect of gut-derived acetate on glucose turnover in man
1988
1. The effect of acetate absorbed from the gut on glucose turnover has been determined in four healthy subjects during both fasting and an intravenous glucose infusion by using [U-13C]glucose. 2. In the first part of the study, after an overnight fast, a tracer dose of [U-13C]glucose was infused at a constant rate along with an infusion of saline for 7 h. In the second part the saline infusion was replaced by glucose at 4.25 mg min−1 kg−1. In both studies 15 mmol of sodium acetate was given by mouth at 15 min intervals from the fourth to the sixth hour. Glucose turnover, respiratory quotient, metabolic rate and blood levels of acetate, 3-hydroxybutyrate, lactate, insulin, glucagon and gastr…