scholarly journals A Metabolomic Approach to Beer Characterization

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1472
Author(s):  
Nicola Cavallini ◽  
Francesco Savorani ◽  
Rasmus Bro ◽  
Marina Cocchi
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Analytical Methods ◽  
Nmr Spectra ◽  
Full Spectrum ◽  
The Past ◽  
Beer Consumption ◽  
Metabolomic Approach ◽  
Chemometric Tools

The consumers’ interest towards beer consumption has been on the rise during the past decade: new approaches and ingredients get tested, expanding the traditional recipe for brewing beer. As a consequence, the field of “beeromics” has also been constantly growing, as well as the demand for quick and exhaustive analytical methods. In this study, we propose a combination of nuclear magnetic resonance (NMR) spectroscopy and chemometrics to characterize beer. 1H-NMR spectra were collected and then analyzed using chemometric tools. An interval-based approach was applied to extract chemical features from the spectra to build a dataset of resolved relative concentrations. One aim of this work was to compare the results obtained using the full spectrum and the resolved approach: with a reasonable amount of time needed to obtain the resolved dataset, we show that the resolved information is comparable with the full spectrum information, but interpretability is greatly improved.

scholarly journals Nuclear Magnetic Resonance Spectroscopy for Medical and Dental Applications: A Comprehensive Review

2019 ◽  
Vol 13 (01) ◽  
pp. 124-128 ◽  
Author(s):  
Komal Zia ◽  
Talal Siddiqui ◽  
Saqib Ali ◽  
Imran Farooq ◽  
Muhammad Sohail Zafar ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Analytical Techniques ◽  
Resonance Spectroscopy ◽  
Advantages And Disadvantages ◽  
The Past ◽  
Dental Applications ◽  
Insight Into ◽  
Nuclear Magnetic

AbstractNuclear magnetic resonance (NMR) spectroscopy is one of the most significant analytical techniques that has been developed in the past few decades. A broad range of biological and nonbiological applications ranging from an individual cell to organs and tissues has been investigated through NMR. Various aspects of this technique are still under research, and many functions of the NMR are still pending a better understanding and acknowledgment. Therefore, this review is aimed at providing a general overview of the main principles, types of this technique, and the advantages and disadvantages of NMR spectroscopy. In addition, an insight into the current uses of NMR in the field of medicine and dentistry and ongoing developments of NMR spectroscopy for future applications has been discussed.

scholarly journals Qualitative and Quantitative Analysis of Heavy Crude Oil Samples and Their SARA Fractions with 13C Nuclear Magnetic Resonance

Processes ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 995
Author(s):  
Ilfat Rakhmatullin ◽  
Sergey Efimov ◽  
Vladimir Tyurin ◽  
Marat Gafurov ◽  
Ameen Al-Muntaser ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Crude Oil ◽  
Functional Groups ◽  
13C Nmr ◽  
Nmr Spectra ◽  
13C Nmr Spectra ◽  
Sara Fractions ◽  
Nuclear Magnetic

Nuclear magnetic resonance (NMR) approaches have unique advantages in the analysis of crude oil because they are non-destructive and provide information on chemical functional groups. Nevertheless, the correctness and effectiveness of NMR techniques for determining saturates, aromatics, resins, and asphaltenes (SARA analysis) without oil fractioning are still not clear. In this work we compared the measurements and analysis of high-resolution 13C NMR spectra in B0 ≈ 16.5 T (NMR frequency of 175 MHz) with the results of SARA fractioning for four various heavy oil samples with viscosities ranging from 100 to 50,000 mPa·s. The presence of all major hydrocarbon components both in crude oil and in each of its fractions was established quantitatively using NMR spectroscopy. Contribution of SARA fractions in the aliphatic (10–60 ppm) and aromatic (110–160 ppm) areas of the 13C NMR spectra were identified. Quantitative fractions of aromatic molecules and oil functional groups were determined. Aromaticity factor and the mean length of the hydrocarbon chain were estimated. The obtained results show the feasibility of 13C NMR spectroscopy for the express analysis of oil from physical properties to the composition of functional groups to follow oil treatment processes.

Separation and Identification of Bridgehead-Substituted Methyl and Ethyl Adamantanes

1968 ◽  
Vol 22 (2) ◽  
pp. 115-120 ◽  
Author(s):  
R. W. Warren ◽  
Abraham Schneider ◽  
E. J. Janoski
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Gas Chromatography ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Adamantane Derivatives ◽  
Saturated Hydrocarbons ◽  
Aluminum Halide

A combination of gas chromatography, infrared and nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry was used to characterize the products obtained from aluminum halide-catalyzed isomerizations of tricyclic saturated hydrocarbons. Six compounds were isolated and identified as methyl and ethyl bridgehead-substituted adamantane derivatives. In addition to supplying evidence pertinent to the structural proof of these derivatives, the data provide useful correlations between infrared, NMR, and mass spectra and methyl and ethyl bridgehead substitution of the adamantane nucleus. A complex splitting pattern which was observed in the NMR spectra of the ethyl-substituted derivatives was shown to be due to the unique A2B3 splitting of the bridgehead-ethyl group.

Synthesis and nuclear magnetic resonance study of the compounds (2-X-1,3-dithiane) (X = H, Me, SiMe3, GeMe3, SnMe3, PbMe3) and their tetracarbonyliron complexes

1978 ◽  
Vol 56 (11) ◽  
pp. 1538-1544 ◽  
Author(s):  
David J. Cane ◽  
William A. G. Graham ◽  
Liviu Vancea
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Energy Barrier ◽  
Nmr Spectra ◽  
Nuclear Magnetic Resonance Study ◽  
Carbonyl Groups ◽  
Magnetic Resonance Study ◽  
Ring Inversion ◽  
C Nmr

A series of (1,3-dithiane)Fe(CO)4 complexes, (2-X-1,3-dithiane)Fe(CO)4, X = H, Me, SiMe3, GeMe3, SnMe3, PbMe3, has been prepared and characterized, and both the complexes and the free ligands studied by 1H and 13C nmr spectroscopy. The energy barrier to ring inversion in (1,3-dithiane)Fe(CO)4, ΔG298†, is 14.7 ± 0.2 kcal mol−1, some 4.4 kcal mol−1 higher than in free 1,3-dithiane.13C nmr spectra showed that within the Fe(CO)4 moiety, rapid averaging of carbonyl groups occurs down to at least −80 °C.

The use of shift reagents and 13C nuclear magnetic resonance for assignment of stereochemistry to oximes

1983 ◽  
Vol 61 (11) ◽  
pp. 2616-2620 ◽  
Author(s):  
Robert R. Fraser ◽  
Raj Capoor ◽  
John W. Bovenkamp ◽  
Benoit V. Lacroix ◽  
Jack Pagotto
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
The Past ◽  
Configurational Assignment ◽  
13C Nuclear Magnetic Resonance ◽  
Proton Data ◽  
Shift Reagents ◽  
C Nmr ◽  
Nuclear Magnetic

The effects of the shift reagents Eu(dpm)3 and Eu(fod)3 on the 1H and 13C nmr spectra of twelve oximes of diverse structure were examined. The proton data show that the use of proton shifts to assign oxime stereochemistry, as has been done in the past, is unreliable. In contrast, Eu(dpm)3 causes LIS values for the 13C signals of α carbons which are strongly dependent on stereochemistry. Signals for all α carbons anti to the oxime oxygen experience large downfield shifts while all syn carbons are either unaffected or shifted upfield. Thus the effects of Eu(dpm)3 on these 13C signals provides an unambiguous method of configurational assignment to oximes. The effects of Eu(fod)3, though similar to Eu(dpm)3, were less consistent and thus less promising for making configurational assignments.

scholarly journals Organoarsenic probes to study proteins by NMR spectroscopy

2021 ◽  
Author(s):  
Mithun Mahawaththa ◽  
Henry Orton ◽  
Ibidolapo Adekoya ◽  
Thomas Huber ◽  
Gottfried Otting ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Protein Nmr ◽  
Structural Studies ◽  
Pseudocontact Shifts ◽  
Paramagnetic Probes ◽  
Loop Regions ◽  
Nuclear Magnetic

Arsenical probes enable structural studies of proteins. We report the first organoarsenic probes for nuclear magnetic resonance (NMR) spectroscopy to study proteins in solutions. These probes can be attached to irregular loop regions. A lanthanide-binding tag induces sizable pseudocontact shifts in protein NMR spectra of a magnitude never observed for small paramagnetic probes before.

Nuclear Magnetic Resonance Studies of Substituted 4-Hydroxy-5-phosphinyl-2-imidazolidinones

1982 ◽  
Vol 36 (4) ◽  
pp. 466-471 ◽  
Author(s):  
John A. Mikroyannidis ◽  
Alexandros K. Tsolis
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Parent Compound ◽  
Proton Nuclear Magnetic Resonance ◽  
Magnetic Resonance Studies ◽  
Aqueous Sodium ◽  
H Nmr ◽  
Nuclear Magnetic

The proton nuclear magnetic resonance (NMR) spectra of some substituted 4-hydroxy-5-phosphinyl-2-imidazolidinones have been studied. The predominance of the cis stereoisomer of these compounds has been also established by 1H NMR spectroscopy. The spectral effects produced by the introduction of the phosphinyl group on the parent compound and by reaction of the substituted 4-hydroxy-5-phosphinyl-2-imidazolidinones with aqueous sodium deuteroxide are discussed. In addition, it has been established by 1H NMR that the product obtained from the reaction of 2-hydroxy-2-(diethoxyphosphinyl)ethanal with N-methylurea was a mixture of 18.2% 1-methyl- and of 81.8% 3-methyl-4-hydroxy-5-diethoxyphosphinyl-2-imidazolidinone.

scholarly journals Rapid Identification of Candida Species by Using Nuclear Magnetic Resonance Spectroscopy and a Statistical Classification Strategy

2003 ◽  
Vol 69 (8) ◽  
pp. 4566-4574 ◽  
Author(s):  
Uwe Himmelreich ◽  
Ray L. Somorjai ◽  
Brion Dolenko ◽  
Ok Cha Lee ◽  
Heide-Marie Daniel ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Yeast Species ◽  
Resonance Spectroscopy ◽  
Statistical Classification ◽  
Accurate Identification ◽  
Classification Strategy ◽  
Nuclear Magnetic

ABSTRACT Nuclear magnetic resonance (NMR) spectra were acquired from suspensions of clinically important yeast species of the genus Candida to characterize the relationship between metabolite profiles and species identification. Major metabolites were identified by using two-dimensional correlation NMR spectroscopy. One-dimensional proton NMR spectra were analyzed by using a staged statistical classification strategy. Analysis of NMR spectra from 442 isolates of Candida albicans, C. glabrata, C. krusei, C. parapsilosis, and C. tropicalis resulted in rapid, accurate identification when compared with conventional and DNA-based identification. Spectral regions used for the classification of the five yeast species revealed species-specific differences in relative amounts of lipids, trehalose, polyols, and other metabolites. Isolates of C. parapsilosis and C. glabrata with unusual PCR fingerprinting patterns also generated atypical NMR spectra, suggesting the possibility of intraspecies discontinuity. We conclude that NMR spectroscopy combined with a statistical classification strategy is a rapid, nondestructive, and potentially valuable method for identification and chemotaxonomic characterization that may be broadly applicable to fungi and other microorganisms.

Synthesis, Characterization, and Modelling of Novel Multifunctional Acryloyl-Based Monomers: An Experimental and Computational Study

2002 ◽  
Vol 55 (10) ◽  
pp. 675 ◽  
Author(s):  
Georgia Patras ◽  
Greg G. Qiao ◽  
David H. Solomon ◽  
Rainer Koch
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Quantum Chemical ◽  
Nmr Spectra ◽  
Computational Study ◽  
Chemical Shifts ◽  
13C Nmr Spectra ◽  
Nmr Spectrum ◽  
Reactive N

Several novel multifunctional monomers with at least three reactive N-acryloyl double bonds have been synthesized and fully characterized. Quantum-chemical calculations and nuclear magnetic resonance (NMR) spectroscopy have been used to predict the structural dissymmetry of these monomers: the simulation of conformers and the NMR spectrum of monomer (3) allows the explanation of the observed 13C NMR spectra as well as a comparison of the performance of several methods for calculating chemical shifts.

Conductivity Studies of Schiff Base Ligands Derived from O-Phenylenediamine and Their Co(II) and Zn(II) Complexes

2015 ◽  
Vol 12 (2) ◽  
pp. 13
Author(s):  
Muhamad Faridz Osman ◽  
Karimah Kassim
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Schiff Base ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Impedance Spectroscopy ◽  
Ftir Spectroscopy ◽  
Coordination Complexes ◽  
Frequency Range ◽  
Schiff Base Ligands

The coordination complexes of Co(II) and Zn(II) with Schiff bases derived from o-phenylenediamine and substituted 2-hydroxybenzaldehyde were prepared All compounds were characterized by Fourier transform infrared (FTIR) spectroscopy and Nuclear magnetic resonance (NMR) spectroscopy elemental analyzers. They were analyzed using impedance spectroscopy in the frequency range of 100Hz-1 MHz. LI and L2 showed higher conductivity compared to their metal complexes, which had values of 1.3 7 x 10-7 and 6.13 x 10-8 S/cm respectively. 

Sign in / Sign up

Export Citation Format

Share Document