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You searched for: Publication year rev 7981-2019 Remove constraint Publication year rev: 7981-2019 Subject term liquid chromatography Remove constraint Subject term: liquid chromatography
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1. (-)-Calcaridine B, a new chiral aminoimidazole-containing alkaloid from the marine sponge Leucetta chagosensis

Author:
Wei-Zhuo Tang; Zhong-Zhen Yang; Fan Sun; Shu-Ping Wang; Fan Yang; Wei-Hua Jiao; Hou-Wen Lin
Source:
Journal of Asian natural products research 2019 v.21 no.11 pp. 1123-1128
ISSN:
1477-2213
Subject:
Porifera; alkaloids; cytotoxicity; human cell lines; imidazole; inhibitory concentration 50; liquid chromatography; neoplasm cells; nuclear magnetic resonance spectroscopy; spectral analysis
Abstract:
... LC-DAD/MS-based dereplication of organic extract of a calcareous sponge Leucetta chagosensis afforded one new chiral aminoimidazole-containing alkaloid, (-)-calcaridine B (1), along with one achiral imidazole analog leucettamine E (2) as well as one known imidazole derivative (2E, 9E)-pyronaamidine-9-(N-methylimine) (3). Their structures were elucidated on the basis of NMR spectroscopic analyses, ...
DOI:
10.1080/10286020.2018.1499729

2. (Un)targeted hair metabolomics: first considerations and systematic evaluation on the impact of sample preparation

Author:
Lisa Eisenbeiss; Andrea E. Steuer; Tina M. Binz; Markus R. Baumgartner; Thomas Kraemer
Source:
Analytical and bioanalytical chemistry 2019 v.411 no.17 pp. 3963-3977
ISSN:
1618-2642
Subject:
acetone; acetonitrile; buffer index; buffers; cutting; decontamination; gas chromatography; grinding; homogenization; liquid chromatography; mass spectrometry; metabolites; metabolomics; methanol; methylene chloride; monitoring; pH; prediction; solvents; urine; washing
Abstract:
... The interest in metabolomic studies has rapidly increased over the past few years. Changes of endogenous compounds are typically detected in plasma or urine. However, the use of hair allows for long-term monitoring of metabolomic changes and has recently started being applied to metabolomic studies. Within the proposed study, we aimed for a systematical investigation of different pre-analytical pa ...
DOI:
10.1007/s00216-019-01873-4

3. 1H NMR and LC-MS-based metabolomic approach for evaluation of the seasonality and viticultural practices in wines from São Francisco River Valley, a Brazilian semi-arid region

Author:
Elenilson G. Alves Filho; Lorena Mara A. Silva; Paulo R.V. Ribeiro; Edy S. de Brito; Guilherme J. Zocolo; Patrícia C. Souza-Leão; Aline T.B. Marques; Amanda L. Quintela; Flemming H. Larsen; Kirley M. Canuto
Source:
Food chemistry 2019 v.289 pp. 558-567
ISSN:
0308-8146
Subject:
caffeic acid; chemometrics; glycerol; harvest date; lactic acid; liquid chromatography; metabolomics; nuclear magnetic resonance spectroscopy; proline; river valleys; rootstocks; secondary metabolites; semiarid zones; succinic acid; tartaric acid; vines; viticulture; wine quality; wines; Brazil
Abstract:
... São Francisco River Valley (SFRV) is a wine-producing semi-arid region in Brazil. Therefore, we used a 1H NMR and UPLC-MS-based metabolomic approach coupled to chemometrics to evaluate the variability in Chenin Blanc and Syrah wines for two harvest seasons, two vine training system and six rootstocks. Overall, the secondary metabolites were influenced by the three factors studied, whereas the prim ...
DOI:
10.1016/j.foodchem.2019.03.103

4. 1H‐NMR metabolomics for evaluating the protective effect of Clinacanthus nutans (Burm. f) Lindau water extract against nitric oxide production in LPS‐IFN‐γ activated RAW 264.7 macrophages

Author:
Leng Wei Khoo; Audrey Siew Foong Kow; Maulidiani Maulidiani; May Yen Ang; Won Yin Chew; Ming Tatt Lee; Chin Ping Tan; Khozirah Shaari; Chau Ling Tham; Faridah Abas
Source:
Phytochemical analysis 2019 v.30 no.1 pp. 46-61
ISSN:
0958-0344
Subject:
Clinacanthus nutans; air drying; amino acids; anti-inflammatory activity; biosynthesis; chemical composition; flavones; glucosides; herbal medicines; inhibitory concentration 50; least squares; leaves; liquid chromatography; macrophages; metabolites; metabolomics; nitric oxide; nuclear magnetic resonance spectroscopy; phytosterols; protective effect; shrubs; solvents; sonication; sulfur; tandem mass spectrometry; triterpenoids
Abstract:
... INTRODUCTION: Clinacanthus nutans, a small shrub that is native to Southeast Asia, is commonly used in traditional herbal medicine and as a food source. Its anti‐inflammation properties is influenced by the metabolites composition, which can be determined by different binary extraction solvent ratio and extraction methods used during plant post‐harvesting stage. OBJECTIVE: Evaluate the relationshi ...
DOI:
10.1002/pca.2789

5. 25-Hydroxyvitamin D Measurement in Human Hair: Results from a Proof-of-Concept study

Author:
Lina Zgaga; Eamon Laird; Martin Healy
Source:
Nutrients 2019 v.11 no.2 pp. -
ISSN:
2072-6643
Subject:
blood circulation; blood sampling; blood serum; hairs; human diseases; liquid chromatography; mass spectrometry; steroid hormones; vitamin D; vitamin D deficiency; vitamin status
Abstract:
... Vitamin D deficiency has been implicated in numerous human diseases leading to an increased interest in assessing vitamin D status. Consequentially, the number of requests for vitamin D measurement keeps dramatically increasing year-on-year. Currently, the recognised best marker of vitamin D status is the concentration of the 25-hydroxyvitamin D (25(OH)D3) in the blood circulation. Whil ...
DOI:
10.3390/nu11020423
PubMed:
30781610
PubMed Central:
PMC6412768

6. 2D Liquid Chromatographic Fractionation with Ultra-high Resolution MS Analysis Resolves a Vast Molecular Diversity of Tropospheric Particle Organics

Author:
Tobias Spranger; Dominik van Pinxteren; Thorsten Reemtsma; Oliver J. Lechtenfeld; Hartmut Herrmann
Source:
Environmental science & technology 2019 v.53 no.19 pp. 11353-11363
ISSN:
1520-5851
Subject:
electrospray ionization mass spectrometry; environmental science; fractionation; liquid chromatography; technology; troposphere
Abstract:
... A 2D-liquid chromatographic fractionation method was combined with direct infusion electrospray ionization Fourier transform-ion cyclotron resonance mass spectrometry to better resolve the high complexity of the organic material in atmospheric particles. The number of assigned molecular formulas increased by a factor of 2.3 for the fractionated sample (18 144) compared to a bulk sample analysis wi ...
DOI:
10.1021/acs.est.9b03839

7. 3,4-Dimethoxycinnamic Acid as a Novel Matrix for Enhanced In Situ Detection and Imaging of Low-Molecular-Weight Compounds in Biological Tissues by MALDI-MSI

Author:
Huixin He; Liang Qin; Yawen Zhang; Manman Han; Jinming Li; Yaqin Liu; Kaidi Qiu; Xiaoyan Dai; Yanyan Li; Maomao Zeng; Huihong Guo; Yijun Zhou; Xiaodong Wang
Source:
Analytical chemistry 2019 v.91 no.4 pp. 2634-2643
ISSN:
1520-6882
Subject:
2,5-dihydroxybenzoic acid; absorption; alkaloids; brain; desorption; flavonoids; graphene oxide; image analysis; ionization; lipids; liquid chromatography; liver; metabolites; nanosilver; oligopeptides; plant tissues; rats; seeds; tandem mass spectrometry
Abstract:
... Low-molecular-weight (low-MW) compounds have many essential functions in biological processes, and the molecular imaging of as many low-MW compounds as possible is critical for understanding complex biological processes. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is an emerging molecular-imaging technology that enables determination of the spatial distributio ...
DOI:
10.1021/acs.analchem.8b03522

8. 3D-Printed Stationary Phases with Ordered Morphology: State of the Art and Future Development in Liquid Chromatography

Author:
Christopher Salmean; Simone Dimartino
Source:
Chromatographia 2019 v.82 no.1 pp. 443-463
ISSN:
0009-5893
Subject:
liquid chromatography; manufacturing; microchip technology; printers
Abstract:
... Stationary phases with precisely ordered morphology have the potential to drastically improve the performance of chromatographic operations, both in the analytical and in the preparative/industrial fields. The recent wave of additive manufacturing, aka 3D printing, gives the unprecedented ability to fabricate such stationary phases and to experimentally prove the theoretical principles of ordered ...
DOI:
10.1007/s10337-018-3671-5

9. 4-Plex Chemical Labeling Strategy Based on Cinchona Alkaloid-Derived Primary Amines for the Analysis of Chiral Carboxylic Acids by Liquid Chromatography-Mass Spectrometry

Author:
Jie Zheng; Shu-Jian Zheng; Chu-Bo Qi; Dong-Mei Wu; Yu-Qi Feng
Source:
Analytical chemistry 2019 v.91 no.17 pp. 11440-11446
ISSN:
1520-6882
Subject:
Cinchona; bioactive properties; blood serum; carboxylic acids; chemical species; colorectal neoplasms; detection limit; enantiomers; energy metabolism; humans; liquid chromatography; mass spectrometry; noninsulin-dependent diabetes mellitus; pathogenesis; patients; primary amines; signal transduction
Abstract:
... Chiral carboxylic acids play important roles in energy metabolism and signal transduction in the human body. These enantiomers usually possess different bioactivities and are also associated with the development of some diseases. Therefore, simultaneous determination of multiple chiral carboxylic acids is vital for study of the pathogenesis of related diseases. However, it is still challenging to ...
DOI:
10.1021/acs.analchem.9b02909

10. 51 Effects of modulating early luteal phase progestin concentration on endometrial function in early pregnant mares

Author:
C. Aurich; T. Beyer; D. Scarlet
Source:
Reproduction, fertility, and development 2019 v.31 no.1 pp. 151
ISSN:
1031-3613
Subject:
biopsy; cell nucleus; cloprostenol; conceptus; cotton; endometrium; epithelial cells; epithelium; free amino acids; glutamic acid; ion exchange; isoleucine; liquid chromatography; lysine; mares; ovulation; pregnancy rate; progesterone; progesterone receptors; secretion; staining; statistical analysis
Abstract:
... Progesterone prepares the endometrium for pregnancy. This requires down-regulation of progesterone receptors in the endometrial epithelium as a prerequisite for the expression of pregnancy-associated proteins. We investigated effects of modulated peripheral progestin concentration in early luteal phase mares on endometrial function on Day 14 of pregnancy. Genitally healthy oestrous mares (n=8; age ...
DOI:
10.1071/RDv31n1Ab51

11. 6 Decelerating embryo development? Characterisation of the uterine environment in European roe deer (Capreolus capreolus) during diapause

Author:
V. A. van der Weijden; A. R. Vegas; V. Milojevic; A. B. Rüegg; J. T. Bick; S. Bauersachs; G. J. Arnold; T. Fröhlich; P. Giesbertz; H. Daniel; B. Drews; S. E. Ulbrich
Source:
Reproduction, fertility, and development 2019 v.31 no.1 pp. 128
ISSN:
1031-3613
Subject:
Capreolus capreolus; DNA; alanine; bioinformatics; biosynthesis; carbon metabolism; cattle; cell adhesion; developmental stages; diapause; embryo culture; embryogenesis; glutamic acid; glutamine; interferons; liquid chromatography; microtubules; models; pregnancy; proteins; serine; sheep; tandem mass spectrometry
Abstract:
... The early developing embryo faces a continuously changing microenvironment to supports its growth. In the European roe deer, this environment accompanies embryonic diapause, a period of up to 4 months in which fertilization and subsequent implantation are decoupled. Diapause is characterised by a deceleration of embryonic growth. In most ruminants such as cattle and sheep, interferon tau (IFNt) pl ...
DOI:
10.1071/RDv31n1Ab6

12. Myrtus Communis Liquor Byproduct as a Source of Bioactive Compounds

Author:
Fabio Correddu; Mariateresa Maldini; Roberta Addis; Giacomo Luigi Petretto; Michele Palomba; Gianni Battacone; Giuseppe Pulina; Anna Nudda; Giorgio Pintore
Source:
Foods 2019 v.8 no.7 pp. -
ISSN:
2304-8158
Subject:
Myrtus communis; antioxidant activity; bioactive compounds; byproducts; carbohydrates; ellagic acid; feed formulation; feeds; industrial applications; ingredients; linoleic acid; liqueurs; liquid chromatography; mass spectrometry; novel foods; pericarp; phenolic acids; polyphenols; polyunsaturated fatty acids; proteins; quercetin; quinic acid; seed extracts; small fruits
Abstract:
... The fatty acid (FA), polyphenol content and evaluation of the antioxidant capacity of exhausted Myrtus communis berries (EMB) resulting from the production of myrtle liqueur were assessed. All parts of the exhausted berries exhibited high concentrations of carbohydrates, proteins, lipids and phenolic compounds. The lipid fraction contained a high amount of poly unsaturated fatty acids (PUFA), main ...
DOI:
10.3390/foods8070237
PubMed:
31262099
PubMed Central:
PMC6678195

13. Olea europaea L. Root Endophyte Bacillus velezensis OEE1 Counteracts Oomycete and Fungal Harmful Pathogens and Harbours a Large Repertoire of Secreted and Volatile Metabolites and Beneficial Functional Genes

Author:
Manel Cheffi; Ali Chenari Bouket; Faizah N. Alenezi; Lenka Luptakova; Marta Belka; Armelle Vallat; Mostafa E. Rateb; Slim Tounsi; Mohamed Ali Triki; Lassaad Belbahri
Source:
Microorganisms 2019 v.7 no.9 pp. -
ISSN:
2076-2607
Subject:
Bacillus velezensis; Fusarium solani; Olea europaea; Phytophthora cryptogea; Phytophthora ramorum; antibiotic resistance; antibiotics; aromatic compounds; biofertilizers; biological control; biological control agents; chemical treatment; disease outbreaks; endophytes; financial economics; forest ecosystems; fungi; gas chromatography-mass spectrometry; genes; genome mining; greenhouse experimentation; growth promotion; human health; liquid chromatography; metals; microbiome; olives; pathogens; phytotoxicity; plant growth; plant growth-promoting rhizobacteria; roots; screening; secondary metabolites; sequence analysis; volatile organic compounds
Abstract:
... Oomycete and fungal pathogens, mainly Phytophthora and Fusarium species, are notorious causal agents of huge economic losses and environmental damages. For instance, Phytophthora ramorum, Phytophthora cryptogea, Phytophthora plurivora and Fusarium solani cause significant losses in nurseries and in forest ecosystems. Chemical treatments, while harmful to the environment and human health, have been ...
DOI:
10.3390/microorganisms7090314
PubMed:
31484434
PubMed Central:
PMC6780883

14. A Comprehensive Peptidomic Approach to Characterize the Protein Profile of Selected Durum Wheat Genotypes: Implication for Coeliac Disease and Wheat Allergy

Author:
Rosa Pilolli; Agata Gadaleta; Luigia Di Stasio; Antonella Lamonaca; Elisabetta De Angelis; Domenica Nigro; Maria De Angelis; Gianfranco Mamone; Linda Monaci
Source:
Nutrients 2019 v.11 no.10 pp. -
ISSN:
2072-6643
Subject:
Triticum turgidum; amino acid sequences; bioinformatics; celiac disease; computer software; digestible protein; durum wheat; epitopes; genetic variation; genotype; immunogenicity; in vitro digestion; liquid chromatography; patients; peptides; plant breeding; protein composition; proteinases; proteins; proteomics; risk assessment; tandem mass spectrometry; tetraploidy; toxicity
Abstract:
... The wheat varietal selection undertaken by breeders in recent decades has been tailored mainly to improve technological and productivity-related traits; however, the latter has resulted in a considerable impoverishment of the genetic diversity of wheat-based products available on the market. This pitfall has encouraged researchers to revalue the natural diversity of cultivated and non-cultivated w ...
DOI:
10.3390/nu11102321
PubMed:
31581419
PubMed Central:
PMC6835779

15. A Dual Perspective of the Action of Lysine on Soybean Oil Oxidation Process Obtained by Combining 1H NMR and LC–MS: Antioxidant Effect and Generation of Lysine–Aldehyde Adducts

Author:
Ana S. Martin-Rubio; Patricia Sopelana; Fumie Nakashima; Takahiro Shibata; Koji Uchida; María D. Guillén
Source:
Antioxidants 2019 v.8 no.9 pp. -
ISSN:
2076-3921
Subject:
antioxidant activity; cooking fats and oils; liquid chromatography; lysine; malondialdehyde; mass spectrometry; nuclear magnetic resonance spectroscopy; oxidation; soybean oil; toxicity
Abstract:
... Little is still known about both the effect of amino acids on the oxidation course of edible oils and the modifications that the former may undergo during this process. Bearing this in mind, the objective of this work was to study the evolution of a system consisting of soybean oil with 2% of l-lysine under heating at 70 °C and stirring conditions, analyzing how the co-oxidation of the oil and ...
DOI:
10.3390/antiox8090326
PubMed:
31438558
PubMed Central:
PMC6770364

16. A Generic Liquid Chromatography−Tandem Mass Spectrometry Exposome Method for the Determination of Xenoestrogens in Biological Matrices

Author:
Karin Preindl; Dominik Braun; Georg Aichinger; Sabina Sieri; Mingliang Fang; Doris Marko; Benedikt Warth
Source:
Analytical chemistry 2019 v.91 no.17 pp. 11334-11342
ISSN:
1520-6882
Subject:
blood serum; breast milk; chemical species; estrogens; exposure assessment; humans; liquid chromatography; neoplasms; pollution; tandem mass spectrometry; urine; xenoestrogens
Abstract:
... We are constantly exposed to a variety of environmental contaminants and hormones, including those mimicking endogenous estrogens. These highly heterogeneous molecules are collectively referred to as xenoestrogens and hold the potential to affect and alter the delicate hormonal balance of the human body. To monitor exposure and investigate potential health implications, comprehensive analytical me ...
DOI:
10.1021/acs.analchem.9b02446

17. A LC-MS/MS method for simultaneous estimation of a novel anti-diabetic combination of saxagliptin and dapagliflozin using a polarity switch approach: application to in vivo rat pharmacokinetic study

Author:
Shruti Surendran; David Paul; Sunil Pokharkar; Abhijeet Deshpande; Sanjeev Giri; Satheeshkumar N.
Source:
Analytical methods 2019 v.11 no.2 pp. 219-226
ISSN:
1759-9679
Subject:
Food and Drug Administration; acetonitrile; ammonia; diabetes; drug formulations; drugs; guidelines; liquid chromatography; pharmacokinetics; rats; solid phase extraction; tandem mass spectrometry
Abstract:
... Diabetes and its associated concerns constitute a major growing health issue in modern society. In the current work we report a highly sensitive, selective and specific LC-MS/MS method for the estimation of a novel anti-diabetic combination of saxagliptin (SAX) and dapagliflozin (DAP) in rat plasma. An Agilent Eclipse Plus C18 column (150 mm × 4.6 mm, 3.6 μm) with gradient elution using 0.01% ammo ...
DOI:
10.1039/c8ay02087f

18. A LC-MS/MS method for the determination of common synthetic cathinones in meconium

Author:
Ángela López-Rabuñal; Elena Lendoiro; Marta Concheiro; Manuel López-Rivadulla; Angelines Cruz; Ana de-Castro-Ríos
Source:
Journal of chromatography 2019 v.1124 pp. 349-355
ISSN:
1570-0232
Subject:
acetonitrile; centrifugation; detection limit; formic acid; liquid chromatography; markets; maternal exposure; methanol; psychotropic agents; solid phase extraction; sonication; tandem mass spectrometry
Abstract:
... New psychoactive substances have been introduced into the market in the last years due to their unregulated status. Synthetic cathinones are one of their main representatives, and they have shown to produce neonatal complications. It is important to have objective tools to identify in utero exposure to drugs that have shown to produce neonatal complications. An analytical method was developed and ...
DOI:
10.1016/j.jchromb.2019.06.030

19. A LC‐MS/MS method for simultaneous determination of seven alkaloids in rat plasma after oral administration of Phellodendri chinensis cortex extract and its application to a pharmacokinetic study

Author:
Zhibin Wang; Mengmeng Song; Binbin Cui; Yixuan Ren; Wenbo Zhu; Bingyou Yang; Haixue Kuang
Source:
Journal of separation science 2019 v.42 no.7 pp. 1351-1363
ISSN:
1615-9306
Subject:
berberine; blood; cortex; ionization; liquid chromatography; liquid-liquid extraction; monitoring; oral administration; pharmacokinetics; rats; tandem mass spectrometry
Abstract:
... A sensitive and rapid liquid chromatography with tandem mass spectrometry method has been developed for simultaneous determination of berberine (I), jateorhizine (II), palmatine (III), tetrahydropalmatine (IV), phellodendrine (V), protopine (VI) and columbamine (VII) in rat plasma after oral administration of Phellodendri chinensis cortex extraction. The plasmas were extracted by liquid‐liquid ext ...
DOI:
10.1002/jssc.201801018

20. A Mediterranean Style Diet Is Favorably Associated with Concentrations of Circulating Ceramides and Ceramide Ratios in the Framingham Offspring Cohort (P18-048-19)

Author:
Maura Walker; Vanessa Xanthakis; Jiantao Ma; Paula A Quatromoni; Lynn Moore; Vasan Ramachandran; Paul Jacques
Source:
Current developments in nutrition 2019 v.3 no.Supplement_1 pp. -
ISSN:
2475-2991
Subject:
Mediterranean diet; alcohols; body mass index; ceramides; cross-sectional studies; energy intake; fish; fruits; legumes; liquid chromatography; mass spectrometry; nuts; physical activity; progeny; red meat; regression analysis; saturated fats; smoking (habit); vegetables; whole grain foods; women
Abstract:
... A Mediterranean style diet may impact cardiometabolic health by modifying concentrations of circulating lipid species. Distinct circulating ceramide species are positively associated with cardiometabolic risk; whereas, ratios of very-long to long-chain ceramides demonstrate an inverse association. We evaluated the relation between consuming a Mediterranean-style diet with concentrations of three c ...
DOI:
10.1093/cdn/nzz039.P18-048-19