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The relative concentration of available inorganic elements is critical for yeast growth and metabolism and has potential to be a tool leading to directed yeast flavour formation during fermentation. This study investigates the influence of essential inorganic elements during alcoholic fermentation of brewers wort, fermented using three independent yeast strains, Saccharomyces pastorianus W34/70, and Saccharomyces cerevisiae strains M2 and NCYC2592 under a range of conditions replicated for each yeast strain. 10 treatments were applied 1 control and 9 inorganic supplementations standard brewers wort, ammonia-nitrogen, inorganic phosphate, potassium, magnesium, copper, zinc, iron, manganese and a composite mixture, Twenty-five chemical markers were evaluated by HPLC (ethanol, glycerol), and GC-MS (aroma). There was a significant change in volatile aroma compounds during fermentation, which was more prominent when supplemented with ammonia nitrogen, inorganic phosphate, potassium or magnesium (P less then 0.05). Heavy metal ions mostly had a negative effect on the flavour formation.The polysaccharide of yam was extracted by hot water method and purified by column chromatography. The physicochemical properties of Chinese yam polysaccharide were analyzed by UV, IR, GPC, 1D-NMR and 2D-NMR spectra. The results showed that Chinese yam polysaccharide had α-d-Gluc-(1 → 4) glycoside bond, and the C2 hydroxyl group was replaced by ethoxyl group. The average molecular weight was determined to be 7.28 × 104. It showed that The scavenging effect of yam polysaccharide on hydroxyl radicals was similar to VC. The sulfated polysaccharide (SP), phosphorylated polysaccharide (PP), carboxymethylated polysaccharide (CP) and acetylated polysaccharide (A-P) were identified by IR and NMR. The results showed that P and its derivatives showed good antioxidant activity. Especially, their scavenging ability to hydroxyl radicals reached the level of VC. This laid a theoretical foundation for the development of yam polysaccharide-related foods.The soluble and insoluble-bound phenolic fractions of hull, whole, and dehulled black and green lentil extracts were identified and quantified using electrospray ionization (ESI)-MS/MS. Several in vitro antioxidant tests and inhibition of DNA strand scission were conducted to assess different pathways of activity. The most abundant phenolics in the soluble fractions were caffeic acid (412.2 μg/g), quercetin, (486.5 μg/g) quercetin glucoside (633.6 μg/g) luteolin glucoside (239.1 μg/g) and formononetin (920 μg/g), while myricetin (534.1 μg/g) and catechin (653.4 μg/g) were the predominant phenolics in the insoluble bound fraction. Hulls of both lentil cultivars had the highest phenolic content and the strongest antioxidant activity followed by whole and dehulled samples. Thus, lentil hulls would serve as an excellent source for the production of functional foods. Moreover, ESI-MS/MS (direct infusion) analysis was the rapid and high-throughput approach for the determination of bioactives in lentils by reducing the analysis time.In this study, an analytical method based on isotope dilution-liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) was developed as a candidate reference method for the determination of sulfonamides (SAs) in honey. To guarantee the accuracy and authenticity, the impact of hydrolysis on bound SA residues was first investigated by enabling (i) identification of sugar-bound SAs, (ii) clarifying the binding reaction rule between the SAs and sugar, (iii) detection of free SAs and sugar-bound SAs, and (iv) preparation of SA-contaminated honey. Thus, the efficiency of different hydrolysis conditions was assessed by comparing the bound SA content before and after hydrolysis. In addition, optimization of the sample pretreatment procedures and LC conditions to minimize matrix effects by separation from significant matrix interferences was also performed. Satisfactory results in terms of hydrolysis efficiency (approximately 88.3%-99.2%), extraction efficiency (84.2%-105.3%), recovery (95.9%-103.1%), and limit of quantification (0.6-1.5 μg·kg-1) were obtained.We here report a comprehensive non-targeted analytical approach to describe the Maillard reaction in beer. By Fourier-transform ion cyclotron mass spectrometry (FT-ICR-MS), we were able to assign thousands of unambiguous molecular formulae to the mass signals and thus directly proceed to the compositional space of 250 analyzed beer samples. Statistical data analyses of the annotated compositions showed that the Maillard reaction is one of the driving forces of beer's molecular diversity leading to key compositional changes in the beer metabolome. Different visualization methods allowed us to map the systematic nature of Maillard reaction derived compounds. The typical molecular pattern, validated by an experimental Maillard reaction model system, pervades over 2,800 (40%) of the resolved small molecules. The major compositional changes were investigated by mass difference network analysis. We were able to reveal general reaction sequences that could be assigned to successive Maillard intermediate phase reactions by shortest path analysis.Inhibition of maltase, sucrase, isomaltase and glucoamylase activity by acarbose, epigallocatechin gallate, epicatechin gallate and four polyphenol-rich tea extract from white, green, oolong, black tea, were investigated by using rat intestinal enzymes and human Caco-2 cells. Regarding rat intestinal enzyme mixture, all four tea extracts were very effective in inhibiting maltase and glucoamylase activity, but only white tea extract inhibited sucrase and isomaltase activity and the inhibition was limited. Mixed-type inhibition on rat maltase activity was observed. Tea extracts in combination with acarbose, produced a synergistic inhibitory effect on rat maltase activity. Caco-2 cells experiments were conducted in Transwells. Green tea extract and epigallocatechin gallate show dose-dependent inhibition on human sucrase activity, but no inhibition on rat sucrase activity. The opposite was observed on maltase activity. The results highlighted the different response in the two investigated model systems and show that tea polyphenols are good inhibitors for α-glucosidase activity.Migration of silver nanoparticles (AgNPs) from food containers (FCs) has been assessed for the first time using a screening method previously validated. Migration was evaluated using water and 3% acetic acid as food simulants (FSs), from 20 to 70 °C at contact times of 2 h and 10 days. Total and migrated Ag were determined by inductively coupled plasma-mass spectrometry (ICP-MS) in the FCs and FSs, respectively. Then, the screening method was validated, and probability of detection (POD) curves were constructed in both FSs to characterize the response to AgNPs. The results provided by the present screening method showed no release of AgNPs. The FSs in contact with FCs were spiked at levels above, inside and below the unreliability region, with a reliability rate (RLR) of 0.90. Asymmetric flow field flow fractionation coupled to inductively coupled plasma mass-spectrometry (AF4-ICP-MS) was used for confirmative analyses.The present investigationwas carried out to determine the effect of germination on pasting, rheological, morphological properties of Kodo millet flour and in-vitroantioxidant characteristics of its phenolic and γ-amino butyric acid extracts. Rheological analysis depicted complex flour viscosity decreased with an improvement in shear intensity, symbolizing the shear-thinning action of flour upon germination. The frequency and temperature sweep demonstrated a decrease in visco-elasticity as a result of germination wherein, SEM revealed destruction in the continuous composite structure of starch which got entangled in dense protein matrix following germination. The in-vitroantioxidant activities such as total antioxidant capacity, DPPH*, FRAP, metal chelating ability and hydrogen peroxide scavenging activities of both the extracts increased significantly. There was a decrease in pasting properties and gelatinization behaviour whereas, visco-elastic solid behaviour changed to visco-elastic fluid. GSK J1 in vitro This research explores the potential of germinated Kodo millet flour for valuable bioactive compounds extraction and its utilization in product development.A new, green, and simple liquid-phase microextraction method namely sieve conducted two syringe-based pressurized liquid-phase microextraction methods was combined with flame atomic absorption spectrometry for the preconcentration and determination of cobalt. For this aim, a novel automated syringe mixing system was developed to be used in the developed extraction procedure. Two syringes were connected to each other by an apparatus having six holes to produce efficient dispersion of the extractant. The pressure created between the two syringes by the forward and backward movements of the syringe plungers created an efficient dispersion of the extractant. In the present study, ligand as complexing agent was synthesized in our laboratory. Limits of detection and quantification were determined to be 1.8 and 6.0 μg L-1, respectively. A 33.7-fold enhancement in detection power was obtained with the developed method. Method was effectively applied for the determination of cobalt in quince samples.Antibiotics are widely used in the prevention and treatment of infectious diseases in animals due to its bactericidal or bacteriostatic action. Residual antibiotics and their metabolites pose great threats to human and animal health, such as potential carcinogenic and mutagenic effects, and bacterial resistances. Therefore, it is necessary and urgent to accurately monitor trace amounts of antibiotics in food samples. Up to now, many analytical methods have been reported for the determination of antibiotics. Biosensors with the advantages of high sensitivity, rapid response, easy miniaturization, and low price have been widely applied to the detection of antibiotics residues in past decades. This review offered an in-depth evaluation of recognition elements for antibiotic residues in diverse food matrices. In addition, it presented a systematical and critical review on signal amplification via various materials, focusing on recently developed nanomaterials. Finally, the review provided an outlook on the future concepts to help upgrade the sensing techniques for antibiotics in food.A magnetic mesoporous molecularly imprinted polymers was synthesized on the surface of magnetic nanoparticles silanized with 3-(trimethoxysilyl) propyl methacrylate to introduce reactive methacrylate groups. Subsequently, methacrylic acid monomers were grafted onto the surface of this adsorbent functionalized via polymerization by precipitation. Magnetic mesoporous molecularly imprinted polymer was properly characterized by different techniques and applied as adsorbent in magnetic solid phase extraction for selective determination of two organophosphorus pesticides, azamethiphos and chlorpyrifos, in mineral water and grape samples. After sample preparation optimization, recoveries of 99.56% and 98.86% were obtained for azamethiphos and chlorpyrifos, respectively. The magnetic solid phase extraction coupled to HPLC-UV presented limit of quantification of 5 ng mL-1, linearity ranged of 5 to 1000 ng mL-1, in addition to adequate accuracy, precision and robustness. The pesticides showed stability in the matrix and were satisfactorily quantified in real mineral water and grape samples.

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