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Beverages ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 56
Author(s):  
Drew Budner ◽  
Joseph Carr ◽  
Brett Serafini ◽  
Samantha Tucker ◽  
Elisabeth Dieckman-Meyer ◽  
...  

There is currently an increased demand for foodstuffs that are classified as gluten-free including beer. Beer produced using gluten-free grains has a distinct flavor profile that differs greatly from that of beer produced from gluten-containing grains. The chemical difference between beers made from these two different grain sources has been explored and some key differences have been identified. Here malt sources containing gluten (barley) and malt without gluten (sorghum) were used to determine which compounds are statistically different based upon their concentrations. A total of 14 (7 barley and 7 sorghum) small-batch beers were made from malt extract. The aroma profile was sampled using SPME with chemical separation and identification and quantification using GC-MS. As expected, the differences were not the result of unique compounds but compounds present in differing amounts. A total of 17 compounds were found to be present in beer brewed from both extracts but in amounts that were highly significantly different.


Author(s):  
Tobias Necke ◽  
Maximilian Trapp ◽  
Stefan Lauterbach ◽  
Georg Amthauer ◽  
Hans-Joachim Kleebe

Abstract In this paper, we report on electron microscopy studies of single crystals of the natural mineral lorándite, TlAsS2. The main focus of this investigation was to address the question as to whether those lorándite crystals are chemically and structurally homogeneous, in order to be utilized as an effective neutrino detector within the lorándite experiment (LOREX) project. Apart from few secondary minerals, being present only at the surface of the lorándite samples, scanning electron microscopy (SEM) indicated homogeneous crystals. Similarly, transmission electron microscopy (TEM) imaging revealed a homogenous and undisturbed crystal structure, with the only exception of local coffee-bean contrasts; however, rarely observed. These specific contrast variations are known to be a typical strain indicator caused by a local deformation of the crystal lattice. Energy-dispersive X-ray spectroscopy (EDS) in conjunction with electron energy-loss spectroscopy (EELS) did not show any significant chemical difference when analysing regions on or off those coffee-bean features, indicating a chemically homogenous mineral. Since the presence of lattice disturbing secondary phase precipitates could be excluded by imaging and complementary chemical analysis, crystal defects such as dislocations and stacking faults or minor fluid inclusions are discussed as the probable origin of this local elastic strain. The experimental results confirm that the studied lorándite single crystals fulfil all structural and chemical requirements to be employed as the natural mineral that allows to determine solar neutrino fluxes. In addition, critical issues regarding the rather challenging sample preparation of lorándite are reported and a quantification of the maximum tolerable electron dose in the TEM is presented, since lorándite was found to be sensitive with respect to electron beam irradiation. Furthermore, the limits of EDS measurements due to peak overlapping are shown and discussed utilizing the case of Pb in lorándite. In this regard, a comparison with the Tl- and Pb-containing natural mineral hutchinsonite, TlPbAs5S9, is also included.


2021 ◽  
Vol 24 ◽  
Author(s):  
Maritiele Naissinger da Silva ◽  
Bruna Lago Tagliapietra ◽  
Franciele Pozzebon Pivetta ◽  
Vinicius do Amaral Flores ◽  
Neila Silvia Pereira dos Santos Richards

Abstract The consumption and consequent production of butter has increased considerably in recent years. In order to know the butters sold in Brazil, the study aimed to analyze butters of Brazilian, French, Italian and Argentine origin. The samples were analyzed for fat content, moisture, Defatted Dry Extract (DDE), and total acidity for comparison with Brazilian legislation. The levels of chlorides, protein, ash, total dry extract, water activity, color and determination of the lipid profile were also determined. In all analyses, there was a statistically significant difference between the samples. Some samples showed disagreement with the quality requirements recommended in Brazilian legislation for commercialization. Indeed, 10 samples did not present the minimum fat content required, varying from 68.53% to 77.31% in butters with salt and from 71.64% to 81.72% in those without salt. Eight samples presented humidity levels above the legal recommendations, varying from 17.05% to 20.28%. All products were in agreement with acidity levels. The predominant fatty acids in all samples were myristic acid (C14: 0), palmitic acid (C16: 0), stearic acid (C18: 0) and oleic acid (C18: 1n9). The regional influence, breed and handling of the animals and season of the year in which the milk was obtained for butter production, were suggested to be the main reason for the physical-chemical difference found between the samples.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Christopher J. Harding ◽  
Simona G. Huwiler ◽  
Hannah Somers ◽  
Carey Lambert ◽  
Luke J. Ray ◽  
...  

Abstract Lysozymes are among the best-characterized enzymes, acting upon the cell wall substrate peptidoglycan. Here, examining the invasive bacterial periplasmic predator Bdellovibrio bacteriovorus, we report a diversified lysozyme, DslA, which acts, unusually, upon (GlcNAc-) deacetylated peptidoglycan. B. bacteriovorus are known to deacetylate the peptidoglycan of the prey bacterium, generating an important chemical difference between prey and self walls and implying usage of a putative deacetyl-specific “exit enzyme”. DslA performs this role, and ΔDslA strains exhibit a delay in leaving from prey. The structure of DslA reveals a modified lysozyme superfamily fold, with several adaptations. Biochemical assays confirm DslA specificity for deacetylated cell wall, and usage of two glutamate residues for catalysis. Exogenous DslA, added ex vivo, is able to prematurely liberate B. bacteriovorus from prey, part-way through the predatory lifecycle. We define a mechanism for specificity that invokes steric selection, and use the resultant motif to identify wider DslA homologues.


Author(s):  
Jingjing Liu ◽  
Simeng Liu ◽  
Tie Shi ◽  
Xiaonan Wang ◽  
Yizhou Chen ◽  
...  

AbstractPrecise classification of seeds is important for agriculture. Due to the slight physical and chemical difference between different types of wheat and high correlation between bands of images, it is easy to fall into the local optimum when selecting the characteristic band of using the spectral average only. In this paper, in order to solve this problem, a new variable fusion strategy was proposed based on successive projection algorithm and the variable importance in projection algorithm to obtain a comprehensive and representative variable feature for higher classification accuracy, within spectral mean and spectral standard deviation, so the 25 feature bands obtained are classified by support vector machine, and the classification accuracy rate reached 83.3%. It indicates that the new fusion strategy can mine the effective features of hyperspectral data better to improve the accuracy of the model and it can provide a theoretical basis for the hyperspectral classification of tiny kernels.


Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3615 ◽  
Author(s):  
Evelyn Rampler ◽  
Dominik Egger ◽  
Harald Schoeny ◽  
Mate Rusz ◽  
Maria Pires Pacheco ◽  
...  

The molecular study of fat cell development in the human body is essential for our understanding of obesity and related diseases. Mesenchymal stem/stromal cells (MSC) are the ideal source to study fat formation as they are the progenitors of adipocytes. In this work, we used human MSCs, received from surgery waste, and differentiated them into fat adipocytes. The combination of several layers of information coming from lipidomics, metabolomics and proteomics enabled network analysis of the biochemical pathways in adipogenesis. Simultaneous analysis of metabolites, lipids, and proteins in cell culture is challenging due to the compound’s chemical difference, so most studies involve separate analysis with unimolecular strategies. In this study, we employed a multimolecular approach using a two–phase extraction to monitor the crosstalk between lipid metabolism and protein-based signaling in a single sample (~105 cells). We developed an innovative analytical workflow including standardization with in-house produced 13C isotopically labeled compounds, hyphenated high-end mass spectrometry (high-resolution Orbitrap MS), and chromatography (HILIC, RP) for simultaneous untargeted screening and targeted quantification. Metabolite and lipid concentrations ranged over three to four orders of magnitude and were detected down to the low fmol (absolute on column) level. Biological validation and data interpretation of the multiomics workflow was performed based on proteomics network reconstruction, metabolic modelling (MetaboAnalyst 4.0), and pathway analysis (OmicsNet). Comparing MSCs and adipocytes, we observed significant regulation of different metabolites and lipids such as triglycerides, gangliosides, and carnitine with 113 fully reprogrammed pathways. The observed changes are in accordance with literature findings dealing with adipogenic differentiation of MSC. These results are a proof of principle for the power of multimolecular extraction combined with orthogonal LC-MS assays and network construction. Considering the analytical and biological validation performed in this study, we conclude that the proposed multiomics workflow is ideally suited for comprehensive follow-up studies on adipogenesis and is fit for purpose for different applications with a high potential to understand the complex pathophysiology of diseases.


2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Xuliang Hao ◽  
Pan He ◽  
Yan Ni ◽  
Jing Yao ◽  
Yankun Yang ◽  
...  

Xueniao capsule, one of the famous traditional Chinese medicine (TCM) formulas, has been proved to be effective for treating acute pyelonephritis (APN) in the clinic. However, the probable mechanisms are still unclear. This study was aimed at investigating the therapeutic effect and action mechanism of Xueniao capsule on acute pyelonephritis rats. Chemical analysis of Xueniao capsule and four different extracts was conducted by HPLC and GC-MS. 21 compounds were identified in the Xueniao capsule, and obvious chemical difference was also revealed among the different extracts by chemical analysis. Metabolomics, combined with bacteriological examination, traditional histopathology, and biochemical parameters, was used to evaluate the effects of Xueniao capsule and four different extracts. After treatment with Xueniao capsule, the bacterial count of urine was decreased and the renal lesions of APN rats were ameliorated by histopathology inspection. Levels of Scr and Ucr, IL-1α, IL-1β, IL-6, IL-10, CXCL-2, and MCP-1 were decreased significantly, and the reserving effect of Xueniao capsule was superior to the different extracts and norfloxacin. 16 endogenous metabolites related to APN model were revealed, and 12 of them could be reversed by the Xueniao capsule. 1H NMR metabolomic results demonstrated that the formula of Xueniao capsule played the best therapeutic role on APN through regulating energy metabolism and alterations of osmotic pressure. The effect of Xueniao capsule on the APN was the synergistic actions of multiple components, which need to be further investigated in future studies.


Author(s):  
Evelyn Rampler ◽  
Dominik Egger ◽  
Harald Schoeny ◽  
Mate Rusz ◽  
Maria Pires Pacheco ◽  
...  

The molecular study of fat cell development in the human body is essential for our understanding of obesity and related diseases. Mesenchymal stem/stromal cells (MSC) are the ideal source to study fat formation as they are the progenitors of adipocytes. In this work, we used human MSCs, received from surgery waste, and differentiate them into fat adipocytes. The combination of several layers of information coming from lipidomics, metabolomics and proteomics enabled comprehensive analysis of the biochemical pathways in adipogenesis. Simultaneous analysis of metabolites, lipids and proteins in cell culture is challenging due to the compound’s chemical difference so that most studies involve separate analysis with unimolecular strategies. In this study, we employed a multimolecular approach using a two–phase extraction to monitor the crosstalk between lipid metabolism and protein-based signaling in a single sample (~105 cells). We developed an innovative analytical workflow including standardization with in-house produced 13C-isotopically labeled compounds, hyphenated high-end mass spectrometry (high-resolution Orbitrap MS) and chromatography (HILIC, RP) for simultaneous untargeted screening and targeted quantification. Metabolite and lipid concentrations ranged over 3-4 orders of magnitude and were detected down to the low fmol (absolute on column) level. Biological validation and data interpretation of the multiomics workflow was performed based on proteomics network reconstruction, metabolic modelling (MetaboAnalyst 4.0) and pathway analysis (OmicsNet). Comparing MSCs and adipocytes, we observed significant regulation of different metabolites and lipids such as triglycerides, gangliosides and carnitine with 113 fully reprogrammed pathways. The observed changes are in accordance with literature findings dealing with adipogenic differentiation of MSC. These results are a proof of principle for the power of multimolecular extraction combined with orthogonal LC-MS assays and network construction. Considering the analytical and biological validation performed in this study, we conclude that the proposed multiomics workflow is ideally suited for comprehensive follow-up studies on adipogenesis and is fit for purpose for different applications.


2018 ◽  
Vol 616 ◽  
pp. A67 ◽  
Author(s):  
V. Allen ◽  
F. F. S. van der Tak ◽  
C. Walsh

Context. In the high-mass star-forming region G35.20−0.74N, small scale (~800 AU) chemical segregation has been observed in which complex organic molecules containing the CN group are located in a small location (toward continuum peak B3) within an apparently coherently rotating structure. Aims. We aim to determine the physical origin of the large abundance difference (~4 orders of magnitude) in complex cyanides within G35.20−0.74 B, and we explore variations in age, gas/dust temperature, and gas density. Methods. We performed gas-grain astrochemical modeling experiments with exponentially increasing (coupled) gas and dust temperature rising from 10 to 500 K at constant H2 densities of 107 cm−3, 108 cm−3, and 109 cm−3. We tested the effect of varying the initial ice composition, cosmic-ray ionization rate (1.3 × 10−17 s−1, 1 × 10−16 s−1, and 6 × 10−16 s−1), warm-up time (over 50, 200, and 1000 kyr), and initial (10, 15, and 25 K) and final temperatures (300 and 500 K). Results. Varying the initial ice compositions within the observed and expected ranges does not noticeably affect the modeled abundances indicating that the chemical make-up of hot cores is determined in the warm-up stage. Complex cyanides vinyl and ethyl cyanide (CH2CHCN and C2H5CN, respectively) cannot be produced in abundances (vs. H2) greater than 5 ×10−10 for CH2CHCN and 2 ×10−10 for C2H5CN with a fast warm-up time (52 kyr), while the lower limit for the observed abundance of C2H5CN toward source B3 is 3.4 ×10−10. Complex cyanide abundances are reduced at higher initial temperatures and increased at higher cosmic-ray ionization rates. Reaction-diffusion competition is necessary to reproduce observed abundances of oxygen-bearing species in our model. Conclusions. Within the context of this model, reproducing the observed abundances toward G35.20−0.74 Core B3 requires a fast warm-up at a high cosmic-ray ionization rate (~1 × 10−16 s−1) at a high gas density (>109 cm−3). The abundances observed at the other positions in G35.20-0.74N also require a fast warm-up but allow lower gas densities (~108 cm−3) and cosmic-ray ionization rates (~1 × 10−17 s−1). In general, we find that the abundance of ethyl cyanide in particular is maximized in models with a low initial temperature, a high cosmic-ray ionization rate, a long warm-up time (>200 kyr), and a lower gas density (tested down to 107 cm−3). G35.20−0.74 source B3 only needs to be ~2000 years older than B1/B2 for the observed chemical difference to be present, which maintains the possibility that G35.20−0.74 B contains a Keplerian disk.


Author(s):  
Qun Sun ◽  
Liwei Zhu ◽  
Wenjing Zhang and Jianhua Wang

In this paper, the physical and chemical differences of seed coat between hard and soft seeds from the same Licorice lot were identified. Electron microscopy-based examination revealed that the cracks on hard seeds coat were much less obvious (shallower and narrower) than those of soft seeds, and that hilar fissure from hard seeds was considerably narrower. Endosperm of hard seeds was markedly thicker than that of soft seeds. Finally, X-ray fluorescence spectrometry revealed significant enrichment for 12 out of the 14 tested mineral elements in hard seed coat. It could be concluded that these above features of hard seeds would increase their resistance to physical impact and protect against cracks in seed coat surface, thus contributing to the impermeability of hard seeds.


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