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You searched for: Subject term 2,5-dihydroxybenzoic acid Remove constraint Subject term: 2,5-dihydroxybenzoic acid
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1. A chemotaxonomic survey of flavonoids and simple phenols in leaves of the Ericaceae

Author:
HARBORNE, J.B.; WILLIAMS, CHRISTINE A.
Source:
Botanical journal of the Linnean Society 1973 v.66 no.1 pp. 37-54
ISSN:
0024-4074
Subject:
2,5-dihydroxybenzoic acid; Calluna; Diapensiaceae; Gaultheria; Phyllodoce; Rhododendron; hydroquinone; leaves; methyl salicylate; surveys
Abstract:
... Leaves of 344 species of the Ericaceae and of 37 species in three related families have been surveyed for flavonoids and simple phenols. The yellow flavonol gossypetin was found in 158 ericaceous species and is of chemotaxonomic interest within the Rhododendroideae (where it occurs in 11 of 19 genera) and in the Vaccinioideae (in 3 of 22 genera). 5-0-methylflavonols appear in 81 species, again mai ...
DOI:
10.1111/j.1095-8339.1973.tb02159.x

2. Phenolsäurezufuhr Erwachsener in einem bayerischen Teilkollektiv der Nationalen Verzehrsstudie

Author:
J. Radtke; J. Linseisen; G. Wolfram
Source:
European journal of nutrition 1998 v.37 no.2 pp. 190-197
ISSN:
1436-6207
Subject:
2,5-dihydroxybenzoic acid; Nationwide Food Consumption Survey; antioxidants; caffeic acid; coronary disease; ellagic acid; food composition; fruits; p-coumaric acid; risk reduction; vegetable consumption
Abstract:
... Phenolic acids, essentially hydroxycinnamic acids and hydroxybenzoic acids, are secondary plant products and commonly found in plant derived foodstuff. The antioxidant and anticarcinogenic properties of phenolic acids could be one of the facts to explain the inverse association between fruit and vegetable intake and the incidence of coronary heart disease and cancer, respectively, as found in epid ...
DOI:
10.1007/s003940050016

3. Detection and activity evaluation of radical scavenging compounds by using DPPH free radical and on-line HPLC-DPPH methods

Author:
Donata Bandonienė; Michael Murkovic; Werner Pfannhauser; Petras Venskutonis; Dainora Gruzdienė
Source:
European food research & technology 2002 v.214 no.2 pp. 143-147
ISSN:
1438-2377
Subject:
2,5-dihydroxybenzoic acid; Salvia; catechin; epicatechin; high performance liquid chromatography; methanol; naringin; phloridzin; plant extracts; quantitative analysis; quercetin; reaction kinetics; screening; uric acid; vanillic acid
Abstract:
... The antiradical activity of crude extracts (80% methanol, 20% water) of S. officinalis, S. glutinosa, S. sclarea and S. aethiopis was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH·) radical scavenging method. For validation of this method several well known antioxidants (ascorbic acid-6-palmitate, gallic, chlorogenic, ferulic, caffeic, uric, gentisic and vanillic acids, catechin, querce ...
DOI:
10.1007/s00217-001-0430-9

4. Fourth 3D Structure of the Chitosan Molecule: Conformation of Chitosan in Its Salts with Medical Organic Acids Having a Phenyl Group

Author:
Makoto KAWAHARA; Toshifumi YUI; Kunio OKA; Peter ZUGENMAIER; Shiho SUZUKI; Shinichi KITAMURA; Kenji OKUYAMA; Kozo OGAWA
Source:
Bioscience, biotechnology, and biochemistry 2003 v.67 no.7 pp. 1545-1550
ISSN:
1347-6947
Subject:
2,5-dihydroxybenzoic acid; aspirin; biotechnology; chitosan; molecular conformation
Abstract:
... Chitosan salts with two medical organic acids having phenyl groups (salicylic and gentisic acids) exhibited fiber diffraction patterns of a new type of crystal which does not compare with known types I and II. The crystals, called type III salts, showed a fiber repeat of 2.550 nm and a meridional reflection at the 5th layer line. These results coupled with a conformational analysis indicate the ch ...
DOI:
10.1271/bbb.67.1545

5. Phenolic acids of Rhaponticum carthamoides

Author:
Skiba, A.; Weglarz, Z.
Source:
Acta horticulturae 2003 no.597 pp. 119-124
ISSN:
0567-7572
Subject:
2,5-dihydroxybenzoic acid; Rhaponticum carthamoides; leaves; plant age; protocatechuic acid; rhizomes; roots
Abstract:
... The relation between the age of plants and the accumulation of phenolic acids, as well as their composition in particular organs of Rhaponticum carthamoides (Willd.) Iljin [Leuzea carthamoides D.C.] was investigated. The content of phenolic acids in rhizomes was higher than in roots (1.40% and 0.85% respectively). The content of these compounds in basal leaves was higher than in stem leaves. Under ...

6. Evaluation of free hydroxyl radical scavenging activities of some Chinese herbs by capillary zone electrophoresis with amperometric detection

Author:
Hui Li; Qingjiang Wang
Source:
Analytical and bioanalytical chemistry 2004 v.378 no.7 pp. 1801-1805
ISSN:
1618-2642
Subject:
2,5-dihydroxybenzoic acid; Ligusticum; Ligustrum lucidum; capillary zone electrophoresis; detection limit; free radical scavengers; herbs; hydroxyl radicals; salicylic acid
Abstract:
... Due to the severe damage caused by free hydroxyl radicals (OH·) to cells and tissues, there is much interest in finding and studying effective and non-toxic OH· scavengers, including traditional Chinese herbs. In this paper, the simple and highly-sensitive technique of capillary zone electrophoresis with amperometric detection (CZE-AD) was used to study the OH· scavenging activities of aqueous ext ...
DOI:
10.1007/s00216-004-2509-1

7. Biodegradation of p-Cresol by Bacillus sp. Strain PHN 1

Author:
Tallur, P. N.; Megadi, V. B.; Kamanavalli, C. M.; Ninnekar, H. Z.
Source:
Current microbiology 2006 v.53 no.6 pp. 529-533
ISSN:
0343-8651
Subject:
2,5-dihydroxybenzoic acid; 4-hydroxybenzoic acid; Bacillus (bacteria); bacteria; biodegradation; bioremediation; carbon; energy; enzyme activity; o-cresol; p-cresol; phenol; soil
Abstract:
... A bacterium capable of utilizing p-cresol as sole source of carbon and energy was isolated from soil and identified as a Bacillus species. The organism also utilized phenol, o-cresol, m-cresol, 4-hydroxybenzoic acid, and gentisic acid as growth substrates. The organism degraded p-cresol to 4-hydroxybenzoic acid, which was further metabolized by a gentisate pathway, as evidenced by isolation and id ...
DOI:
10.1007/s00284-006-0309-x
PubMed:
17106800

8. Design of a method for generation of gas-phase hydroxyl radicals, and use of HPLC with fluorescence detection to assess the antioxidant capacity of natural essential oils

Author:
Pezo, D.; Salafranca, J.; Nerín, C.
Source:
Analytical and bioanalytical chemistry 2006 v.385 no.7 pp. 1241-1246
ISSN:
1618-2642
Subject:
essential oils; salicylic acid; reversed-phase high performance liquid chromatography; ultraviolet radiation; aqueous solutions; fluorescence; hydrogen peroxide; air; oxidation; ginger; Zingiber officinale; humans; detectors; oxidants; antioxidant activity; diet; hydroxyl radicals; 2,5-dihydroxybenzoic acid; quartz; pH; air flow
Abstract:
... The use of natural antioxidants is of increasing importance in the human diet, because they are recognised as compounds essential to health which minimize or delay the aging process. Despite apparent simplicity, however, it is very difficult to measure and quantify such properties, for which a robust analytical method is required. Because oxidation usually is caused by the presence of OH· radicals ...
DOI:
10.1007/s00216-006-0395-4
PubMed:
16570142

9. Ionic (liquid) matrices for matrix-assisted laser desorption/ionization mass spectrometry--applications and perspectives

Author:
Tholey, Andreas; Heinzle, Elmar
Source:
Analytical and bioanalytical chemistry 2006 v.386 no.1 pp. 24-37
ISSN:
1618-2642
Subject:
2,5-dihydroxybenzoic acid; desorption; image analysis; ionization; mass spectrometry; mixtures; molecular weight; proteome; pyridines; sampling
Abstract:
... A large number of matrix substances have been used for various applications in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). The majority of matrices applied in ultraviolet-MALDI MS are crystalline, low molecular weight compounds. A problem encountered with many of these matrices is the formation of hot spots, which lead to inhomogeneous samples, thus leading to increas ...
DOI:
10.1007/s00216-006-0600-5
PubMed:
16830111

10. Comparative TOF-SIMS and MALDI TOF-MS analysis on different chromatographic planar substrates

Author:
Talian, Ivan; Orinák, Andrej; Preisler, Jan; Heile, Andreas; Onofrejová, Lucie; Kaniansky, Dušan; Arlinghaus, Heinrich F.
Source:
Journal of separation science 2007 v.30 no.16 pp. 2570-2582
ISSN:
1615-9306
Subject:
2,5-dihydroxybenzoic acid; Raman spectroscopy; chromatography; desorption; ferulic acid; gibberellic acid; ionization; mass spectrometry; silica gel
Abstract:
... A comparison is made between two high resolution, surface-based, mass spectrometric methods: time-of-flight secondary ion mass spectrometry (TOF-SIMS) and matrix-assisted laser desorption/ionisation mass spectrometry (MALDI TOF-MS) in indication of abietic and gibberellic acids molecular profiles on different chromatographic thin layers. The analytes were applied to silica gel chromatographic thin ...
DOI:
10.1002/jssc.200700120
PubMed:
17876765

11. Enhancement of fludioxonil fungicidal activity by disrupting cellular glutathione homeostasis with 2,5-dihydroxybenzoic acid

Author:
Kim, Jong H.; Campbell, Bruce C.; Mahoney, Noreen; Chan, Kathleen L.; Molyneux, Russell J.; May, Gregory S.
Source:
FEMS microbiology letters 2007 v.270 no.2 pp. 284-290
ISSN:
0378-1097
Subject:
Aspergillus oryzae; Aspergillus flavus; glutathione; Aspergillus parasiticus; Aspergillus niger; Aspergillus nidulans; antifungal agents; fungicides; signal transduction; animal pathogenic fungi; synergism; Aspergillus fumigatus; homeostasis; plant pathogenic fungi; benzoic acid; pyrroles; antioxidant activity; mitogen-activated protein kinase; oxidative stress
Abstract:
... The activity of fludioxonil, a phenylpyrrole fungicide, is elevated by coapplication of the aspirin/salicylic acid metabolite, 2,5-dihydroxybenzoic acid (2,5-DHBA). Fludioxonil activity is potentiated through a mitogen-activated protein kinase (MAPK) pathway that regulates osmotic/oxidative stress-responses. 2,5-DHBA disrupts cellular GSH (reduced glutathione)/GSSG (oxidized glutathione) homeostas ...
Handle:
10113/16471
DOI:
10.1111/j.1574-6968.2007.00682.x
PubMed:
17355596

12. Rapid fingerprinting of red wines by MALDI mass spectrometry

Author:
Carpentieri, Andrea; Marino, Gennaro; Amoresano, Angela
Source:
Analytical and bioanalytical chemistry 2007 v.389 no.3 pp. 969-982
ISSN:
1618-2642
Subject:
2,5-dihydroxybenzoic acid; anthocyanins; desorption; ionization; matrix-assisted laser desorption-ionization mass spectrometry; red wines
Abstract:
... Here we report a simple and fast method for wine fingerprinting based on direct matrix-assisted laser desorption/ionization (MALDI) mass spectrometry analysis of different red wine samples, useful for batch-to-batch analysis and for the detection of key compounds even in trace amounts which may vary from vintage to vintage, and from one treatment to another one. A series of 20 samples from differe ...
DOI:
10.1007/s00216-007-1476-8
PubMed:
17653534

13. Automated normal phase nano high performance liquid chromatography/matrix assisted laser desorption/ionization mass spectrometry for analysis of neutral and acidic glycosphingolipids

Author:
Zarei, Mostafa; Kirsch, Stephan; Müthing, Johannes; Bindila, Laura; Peter-Katalinić, Jasna
Source:
Analytical and bioanalytical chemistry 2008 v.391 no.1 pp. 289-297
ISSN:
1618-2642
Subject:
2,5-dihydroxybenzoic acid; cations; crystallization; desorption; erythrocytes; glycosphingolipids; high performance liquid chromatography; humans; ionization; lithium; mass spectrometry; mice; screening; solvents
Abstract:
... The coupling of nano high-performance liquid chromatography (nanoHPLC) with matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) via an automatic spotting roboter was developed and adapted for the first time for the analysis of complex mixtures of glycosphingolipids (GSLs). The 2,5-dihydroxybenzoic acid and 6-azo-2-thiothymine matrix systems were adjusted to concurrently meet ...
DOI:
10.1007/s00216-008-1932-0
PubMed:
18327675

14. Measurement of Hydroxyl-Radical Formation in the Rat Striatum by In Vivo Microdialysis and GC-MS

Author:
Nguyen, Vien; Bonds, Darius V.; Prokai, Laszlo
Source:
Chromatographia 2008 v.68 no.1 pp. 57-62
ISSN:
0009-5893
Subject:
2,5-dihydroxybenzoic acid; brain; derivatization; dissociation; gas chromatography-mass spectrometry; glutamic acid; ionization; ions; liquid-liquid extraction; microdialysis; monitoring; oxidative stress; rats; reactive oxygen species; salicylic acid; tandem mass spectrometry
Abstract:
... A GC-MS method was developed for measuring hydroxyl-radical capture products of salicylic acid, a common trapping agent for this reactive oxygen species, in samples obtained by in vivo cerebral microdialysis experiments. The assay employed liquid-liquid extraction followed by derivatization of 2,3- and 2,5-dihydroxybenzoic acid, along with 3,5-dihydroxybenzoic acid added as an internal standard. D ...
DOI:
10.1365/s10337-008-0703-6
PubMed:
19802331
PubMed Central:
PMC2600797

15. Metabolism of salicylic acid in wild-type, ugt74f1 and ugt74f2 glucosyltransferase mutants of Arabidopsis thaliana

Author:
Dean, John V.; Delaney, Sean P.
Source:
Physiologia plantarum 2008 v.132 no.4 pp. 417-425
ISSN:
0031-9317
Subject:
2,5-dihydroxybenzoic acid; Arabidopsis thaliana; enzymes; esters; glucose; leaves; metabolism; metabolites; mutants; plant architecture; salicylic acid
Abstract:
... Arabidopsis thaliana contains two salicylic acid (SA) glucosyltransferase enzymes designated UGT74F1 and UGT74F2. UGT74F1 forms only SA 2-O-β-D-glucose (SAG), while UGT74F2 forms both SAG and the SA glucose ester (SGE). In an attempt to determine the in vivo role of each SA glucosyltransferase (SAGT), the metabolism of SA in ugt74f1 and ugt74f2 mutants was examined and compared with that of the wi ...
DOI:
10.1111/j.1399-3054.2007.01041.x
PubMed:
18248508

16. Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) of low molecular weight organic compounds and synthetic polymers using zinc oxide (ZnO) nanoparticles

Author:
Watanabe, Takehiro; Kawasaki, Hideya; Yonezawa, Tetsu; Arakawa, Ryuichi
Source:
Journal of mass spectrometry 2008 v.43 no.8 pp. 1063-1071
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; citric acid; desorption; ionization; mass spectrometry; molecular weight; nanoparticles; phospholipids; polyethylene glycol; polymethylmethacrylate; polypropylenes; polystyrenes; testosterone; verapamil; zinc oxide
Abstract:
... We have developed surface-assisted laser desorption/ionization mass spectrometry using zinc oxide (ZnO) nanoparticles with anisotropic shapes (ZnO-SALDI-MS). The mass spectra showed low background noises in the low m/z, i.e. less than 500 u region. Thus, we succeeded in SALDI ionization on low molecular weight organic compounds, such as verapamil hydrochloride, testosterone, and polypropylene glyc ...
DOI:
10.1002/jms.1385

17. 2-(2-Aminoethylamino)-5-nitropyridine as a basic matrix for negative-mode matrix-assisted laser desorption/ionization analysis of phospholipids

Author:
Lorkiewicz, Pawel; Cecilia Yappert, M.
Source:
Journal of mass spectrometry 2009 v.44 no.1 pp. 137-143
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; automation; desorption; ethanolamine; ionization; mass spectrometry; mixtures; phosphatidylcholines; phosphatidylserines; soybeans; sphingomyelins; zwitterions
Abstract:
... Fast and easy analysis of phospholipids (PLs) by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been well demonstrated. However, when using common organic matrices, such as 2,5-dihydroxybenzoic acid (DHB), the detection of most PL classes in positive-ion mode is difficult when PLs containing zwitterionic groups, such as phosphatidylcholines (PCs) and sphingomyelins (S ...
DOI:
10.1002/jms.1483

18. Alkali-hydroxide-doped matrices for structural characterization of neutral underivatized oligosaccharides by MALDI time-of-flight mass spectrometry

Author:
Tzeng, Yan-Kai; Zhu, Zhiqiang; Chang, Huan-Cheng
Source:
Journal of mass spectrometry 2009 v.44 no.3 pp. 375-383
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; aqueous solutions; beta-cyclodextrin; derivatization; desorption; dextran; hexoses; ionization; ions; isomers; lithium; mass spectrometry; mixing; oligosaccharides; sodium hydroxide
Abstract:
... We report new approaches using alkali-hydroxide-doped matrices to facilitate structural characterization of neutral underivatized oligosaccharides by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) MS. The approaches involved pretreatment of the analytes with NaOH or LiOH in aqueous solution, followed by mixing them with MALDI matrices prior to MS analysis. It was found th ...
DOI:
10.1002/jms.1515

19. Characterization of natural wax esters by MALDI-TOF mass spectrometry

Author:
Vrkoslav, Vladimír; Míková, Radka; Cvačka, Josef
Source:
Journal of mass spectrometry 2009 v.44 no.1 pp. 101-110
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; Ginkgo biloba; carbon; cesium; copper; desorption; detection limit; gas chromatography-mass spectrometry; glass; insects; ionization; ions; isotopes; leaf extracts; lithium; matrix-assisted laser desorption-ionization mass spectrometry; mixing; molecular weight; potassium; rubidium; salts; sampling; scanning electron microscopy; silver; sodium; solubility; solvents; wax esters
Abstract:
... The applicability of matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) to the analysis of wax esters (WEs) was investigated. A series of metal salts of 2,5-dihydroxybenzoic acid (DHB) was synthesized and tested as possible matrices. Alkali metal (Li, Na, K, Rb, Cs) and transition metal (Cu, Ag) salts were studied. The matrix properties were evaluated, incl ...
DOI:
10.1002/jms.1476

20. Combining tissue extraction and off-line capillary electrophoresis matrix-assisted laser desorption/ionization Fourier transform mass spectrometry for neuropeptide analysis in individual neuronal organs using 2,5-dihydroxybenzoic acid as a multi-functional agent

Author:
Wang, Junhua; Jiang, Xiaoyue; Sturm, Robert M.; Li, Lingjun
Source:
Journal of chromatography 2009 v.1216 no.47 pp. 8283-8288
ISSN:
0021-9673
Subject:
2,5-dihydroxybenzoic acid; Cancer borealis; aqueous solutions; capillary electrophoresis; chromatography; crabs; desorption; drying; electrolytes; ionization; mass spectrometry; neuropeptides
Abstract:
... In this study we report an improved protocol that combines simplified sample preparation and micro-scale separation for mass spectrometric analysis of neuropeptides from individual neuroendocrine organs of crab Cancer borealis. A simple, one-step extraction method with commonly used matrix-assisted laser desorption/ionization (MALDI) matrix, 2,5-dihydroxybenzoic acid (DHB), in saturated aqueous so ...
DOI:
10.1016/j.chroma.2009.04.085
PubMed:
19473662
PubMed Central:
PMC2783529

21. Comparison of motility, recovery, and methyl-thiazolyl-tetrazolium reduction assays for use in screening plant products for anthelmintic activity

Author:
Smith, Robert A.; Pontiggia, Laura; Waterman, Carrie; Lichtenwalner, Meghan; Wasserman, Jared
Source:
Parasitology research 2009 v.105 no.5 pp. 1339-1343
ISSN:
0932-0113
Subject:
2,5-dihydroxybenzoic acid; Anogeissus; Caenorhabditis elegans; gallic acid; high performance liquid chromatography; levamisole; plant extracts; salts
Abstract:
... The primary objective of these experiments was to compare the effectiveness of motility, recovery, and methyl-thiazolyl-tetrazolium (MTT) reduction assays for determining anthelmintic activity of plant extracts and purified compounds from these extracts. Caenorhabditis elegans was used as the test organism. High-performance liquid chromatography (HPLC) grade water and M9 medium were used as the so ...
DOI:
10.1007/s00436-009-1560-4
PubMed:
19629527

22. Flavonoid-matrix cluster ions in MALDI mass spectrometry

Author:
Madeira, Paulo J. Amorim; Florêncio, M. Helena
Source:
Journal of mass spectrometry 2009 v.44 no.7 pp. 1105-1113
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; desorption; ionization; ions; kaempferol; luteolin; matrix-assisted laser desorption-ionization mass spectrometry; myricetin; quercetin; tandem mass spectrometry
Abstract:
... The behaviour of 2,5-dihydroxybenzoic acid (2,5-DHB) matrix under matrix-assisted laser desorption/ionisation (MALDI) conditions was investigated, and the formation of 2,5-DHB cluster ions, mainly dehydrated 2,5-DHB ions, is reported. Interestingly, in the mass spectra of this compound, besides dimers and trimers, protonated tetramers, pentamers, hexamers and heptamers were also found with signifi ...
DOI:
10.1002/jms.1588

23. Influence of training system on chromatic characteristics and phenolic composition in red wines

Author:
Río Segade, S.; Soto Vázquez, E.; Vázquez Rodríguez, E. I.; Rego Martínez, J. F.
Source:
European food research & technology 2009 v.229 no.5 pp. 763-770
ISSN:
1438-2377
Subject:
2,5-dihydroxybenzoic acid; Vitis vinifera; color; cultivars; flavanols; grapes; ionization; principal component analysis; red wines; vines; yields
Abstract:
... Chromatic characteristics and phenolic composition of red wines elaborated from Sousón and Brancellao grapes (Vitis vinifera L.), whose vines were trained in cordon and Guyot systems, were determined. This comparison was possible because there were no significant differences between yields for each one. Hue was the only significantly different chromatic parameter for both training systems and cult ...
DOI:
10.1007/s00217-009-1112-2

24. Metal ion attachment to the matrix meso-tetrakis(pentafluorophenyl)porphyrin, related matrices and analytes: an experimental and theoretical study

Author:
van Kampen, Jeroen J.A.; Luider, Theo M.; Ruttink, Paul J.A.; Burgers, Peter C.
Source:
Journal of mass spectrometry 2009 v.44 no.11 pp. 1556-1564
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; analytical chemistry; antiretroviral agents; cations; cesium; cobalt; copper; desorption; drugs; ethylene glycol; hydrogen; ionization; iron; lithium; mass spectrometry; metal ions; potassium; protoporphyrin; quantitative analysis; rubidium; salts; skeleton; sodium; zinc
Abstract:
... In a previous study [van Kampen et al. Analytical Chemistry 2006; 78: 5403], we found that meso-tetrakis (pentafluorophenyl)porphyrin (F20TPP), in combination with lithium salts, provides an efficient matrix to cationize small molecules by Li⁺ attachment and that this combination can be successfully applied to the quantitative analysis of drugs, such as antiretroviral compounds using matrix-assist ...
DOI:
10.1002/jms.1601

25. Multiresidue analysis of pollutants as their trimethylsilyl derivatives, by gas chromatography-mass spectrometry

Author:
Sebők, Á.; Vasanits-Zsigrai, A.; Helenkár, A.; Záray, Gy.; Molnár-Perl, I.
Source:
Journal of chromatography 2009 v.1216 no.12 pp. 2288-2301
ISSN:
0021-9673
Subject:
derivatization; ions; 2,5-dihydroxybenzoic acid; pollutants; cholesterol; phthalates; pH; dicarboxylic acids; multiresidue analysis; acetaminophen; saturated fatty acids; benzoic acid; wastewater; solid phase extraction; gas chromatography-mass spectrometry; Danube River
Abstract:
... This paper reports a multiresidue analysis procedure which permits the identification and quantification of sixty-three water-soluble pollutants. Subsequent to their solid-phase extraction (SPE) enrichment, analyses of species have been carried out from one solution, by a single injection, as their trimethylsilyl-oxime ether/ester derivatives, by gas chromatography-mass spectrometry, within 31min. ...
DOI:
10.1016/j.chroma.2009.01.056

26. Phosphopeptide enrichment using microscale titanium dioxide solid phase extraction

Author:
Ying‐Qing Yu; Jennifer Fournier; Martin Gilar; John C. Gebler
Source:
Journal of separation science 2009 v.32 no.8 pp. 1189-1199
ISSN:
1615-9306
Subject:
2,5-dihydroxybenzoic acid; additives; affinity chromatography; carboxylic acids; ionization; peptides; solid phase extraction; titanium dioxide; yeasts
Abstract:
... Identification of phosphopeptides by MS is challenging due to their relatively low abundance in proteomic samples and their limited ionization efficiency. Various affinity enrichment methods have been used in the literature. Titanium dioxide SPE devices have been recently proposed as an alternative to immobilized metal affinity chromatography for phosphopeptide enrichment. This study evaluates the ...
DOI:
10.1002/jssc.200800652
PubMed:
19301321

27. The effect of temperature on the stability of compounds used as UV-MALDI-MS matrix: 2,5-dihydroxybenzoic acid, 2,4,6-trihydroxyacetophenone, α-cyano-4-hydroxycinnamic acid, 3,5-dimethoxy-4-hydroxycinnamic acid, nor-harmane and harmane

Author:
Tarzi, Olga I.; Nonami, Hiroshi; Erra-Balsells, Rosa
Source:
Journal of mass spectrometry 2009 v.44 no.2 pp. 260-277
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; carbon dioxide; desorption; electrospray ionization mass spectrometry; fluorescence; heat; ionization; isomerization; melting point; nuclear magnetic resonance spectroscopy; sublimation; temperature; thermal stability; thin layer chromatography
Abstract:
... The thermal stability of several commonly used crystalline matrix-assisted ultraviolet laser desorption/ionization mass spectrometry (UV-MALDI-MS) matrices, 2,5-dihydroxybenzoic acid (gentisic acid; GA), 2,4,6-trihydroxyacetophenone (THA), α-cyano-4-hydroxycinnamic acid (CHC), 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid; SA), 9H-pirido[3,4-b]indole (nor-harmane; nor-Ho), 1-methyl-9H-pirid ...
DOI:
10.1002/jms.1506

28. 1H-Pteridine-2,4-dione (lumazine): a new MALDI matrix for complex (phospho)lipid mixtures analysis

Author:
Calvano, Cosima D.; Carulli, Saverio; Palmisano, Francesco
Source:
Analytical and bioanalytical chemistry 2010 v.398 no.1 pp. 499-507
ISSN:
1618-2642
Subject:
2,5-dihydroxybenzoic acid; absorption; cations; desorption; eggs; hens; ionization; mass spectrometry; milk; phosphatidylcholines; phosphatidylethanolamines; phosphatidylglycerols; phosphatidylinositols; phosphatidylserines; soymilk; sphingomyelins
Abstract:
... Nowadays, matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry represents an emerging and versatile tool for analysis of lipids. However, direct (i.e., with no previous separation of lipid classes) analysis of crude extracts containing a complex mixture of lipids (a problem typically encountered in shotgun lipidomics) is still a quite challenging task using a conven ...
DOI:
10.1007/s00216-010-3927-x
PubMed:
20593166

29. A fast, reproducible and low-cost method for sequence deconvolution of 'on-bead' peptides via 'on-target' maldi-TOF/TOF mass spectrometry

Author:
Amadei, Giulio A.; Cho, Choi-Fong; Lewis, John D.; Luyt, Leonard G.
Source:
Journal of mass spectrometry 2010 v.45 no.3 pp. 241-251
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; desorption; image analysis; instrumentation; ligands; mass spectrometry; peptides; polystyrenes; screening; sequence analysis
Abstract:
... A novel approach to high-throughput sequence deconvolution of on-bead small peptides (MW < 2000 Da) using on-target MALDI-TOF/TOF instrumentation is presented. Short peptides of pentamer and octamer length, covalently attached to TentaGel polystyrene beads through a photolabile linker, were placed onto the MALDI target, apportioned with suitable matrix (2,5-dihydroxybenzoic acid) and then hit with ...
DOI:
10.1002/jms.1708

30. Antioxidant activity and chemical difference in fruit of different Actinidia sp.

Author:
Piotr Latocha; Tomasz Krupa; Rafał Wołosiak; Elwira Worobiej; Jacek Wilczak
Source:
International journal of food sciences and nutrition 2010 v.61 no.4 pp. 381-394
ISSN:
1465-3478
Subject:
2,5-dihydroxybenzoic acid; Actinidia arguta; Actinidia deliciosa; Actinidia kolomikta; Actinidia melanandra; antioxidant activity; ascorbic acid; carotenoids; chlorophyll; flavonoids; fruits; high performance liquid chromatography; nutrition; tannins
Abstract:
... The present research aimed at evaluating the vitamin C, total phenolic content (TPC), phenolic compounds, carotenoids, and chlorophyll contents, as well as antioxidant activity (AAC) of six Actinidia species fruit. Vitamin C, phenolic compounds, carotenoids and chlorophylls were measured using high-performance liquid chromatography. TPC was determined using the Folin–Ciocalteau reagent, and AAC us ...
DOI:
10.3109/09637480903517788

31. Comparison of sample pre-treatments for laser desorption ionization and secondary ion mass spectrometry imaging of Miscanthus × giganteus

Author:
Li, Zhen; Bohn, Paul W.; Sweedler, Jonathan V.
Source:
Bioresource technology 2010 v.101 no.14 pp. 5578-5585
ISSN:
0960-8524
Subject:
2,5-dihydroxybenzoic acid; Miscanthus; carbohydrates; chemical speciation; coatings; desorption; feedstocks; fuel production; grasses; image analysis; ionization; ions; lasers; mass spectrometry; metals; vascular bundles
Abstract:
... Efforts to further the potential of the large perennial grass Miscanthus × giganteus as a biofuel feedstock would be aided by the ability to image the chemical species present during the fuel production process. Toward this end, two mass spectrometry imaging (MSI) approaches have been investigated here—laser desorption/ionization mass spectrometry (LDI-MS) and secondary ion mass spectrometry (SIMS ...
DOI:
10.1016/j.biortech.2010.01.136

32. Far infrared-assisted extraction followed by capillary electrophoresis for the determination of bioactive constituents in the leaves of Lycium barbarum Linn

Author:
Duan, Haotian; Chen, Yi; Chen, Gang
Source:
Journal of chromatography 2010 v.1217 no.27 pp. 4511-4516
ISSN:
0021-9673
Subject:
2,5-dihydroxybenzoic acid; Lycium barbarum; bioactive properties; capillary electrophoresis; carbon; chromatography; detection limit; electrodes; irradiation; leaves; pH; quercetin; rutin
Abstract:
... In this work, a method based on capillary electrophoresis with amperometric detection and far infrared-assisted extraction has been developed for the determination of rutin, gentisic acid, and quercetin in the leaves of Lycium barbarum Linn. The effects of detection potential, irradiation time, and the voltage applied on the infrared generator were investigated to acquire the optimum analysis cond ...
DOI:
10.1016/j.chroma.2010.04.069

33. Ionic liquid matrices for MALDI-TOF-MS analysis of intact glycoproteins

Author:
Giménez, Estela; Benavente, Fernando; Barbosa, José; Sanz-Nebot, Victoria
Source:
Analytical and bioanalytical chemistry 2010 v.398 no.1 pp. 357-365
ISSN:
1618-2642
Subject:
2,5-dihydroxybenzoic acid; crystallization; glycoproteins; glycosylation; ionic liquids; ionization; matrix-assisted laser desorption-ionization mass spectrometry; molecular weight; sugars; vacuum drying
Abstract:
... 2,5-Dihydroxybenzoic acid (DHB) has been demonstrated to be a more suitable matrix than 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid, SA) to obtain reliable molecular mass values of intact glycoproteins because it prevents sugar fragmentation. Lack of spot homogeneity during the crystallization step was prevented by drying the sample-matrix mixture under vacuum conditions. Nevertheless, th ...
DOI:
10.1007/s00216-010-3898-y
PubMed:
20607524

34. Molecular cloning and characterization of a novel tomato xylosyltransferase specific for gentisic acid

Author:
Tárraga, Susana; Lisón, Purificación; López-Gresa, María Pilar; Torres, Cristina; Rodrigo, Ismael; Bellés, José María; Conejero, Vicente
Source:
Journal of experimental botany 2010 v.61 no.15 pp. 4325-4338
ISSN:
0022-0957
Subject:
tomatoes; messenger RNA; plant diseases and disorders; sugars; complementary DNA; Komagataella pastoris; enzymes; 2,5-dihydroxybenzoic acid; signal transduction; genes; disease resistance; molecular cloning; salicylic acid; plant proteins
Abstract:
... The importance of salicylic acid (SA) in the signal transduction pathway of plant disease resistance has been well documented in many incompatible plant-pathogen interactions, but less is known about signalling in compatible interactions. In this type of interaction, tomato plants have been found to accumulate high levels of 2,5-dihydroxybenzoic acid (gentisic acid, GA), a metabolic derivative of ...
DOI:
10.1093/jxb/erq234
PubMed:
20729481
PubMed Central:
PMC2955746

35. Rapid Determination of Simple Polyphenols in Grapes by LC Using a Monolithic Column

Author:
Liazid, Ali; Barbero, Gerardo F.; Palma, Miguel; Brigui, Jamal; Barroso, Carmelo G.
Source:
Chromatographia 2010 v.72 no.5-6 pp. 417-424
ISSN:
0009-5893
Subject:
2,5-dihydroxybenzoic acid; acetic acid; caffeic acid; catechin; chromatography; detectors; epicatechin; ferulic acid; fluorescence; gallic acid; grapes; methanol; p-coumaric acid; polyphenols; resveratrol; sinapic acid; solvents; temperature; vanillin
Abstract:
... The development of a rapid, reliable and reproducible LC method for the determination and quantification of 13 polyphenols (gallic acid, protocatechuic aldehyde, gentisic acid, catechin, vanillinic acid, caffeic acid, vanillin, epicatechin, syringaldehyde, p-coumaric acid, ferulic acid, sinapic acid and resveratrol) in grapes and derived products is reported. The polyphenols were separated in less ...
DOI:
10.1365/s10337-010-1678-7

36. The selective induction of the phenylalanine ammonia-lyase pathway in the resistance response of wheat to the russian wheat aphid

Author:
J. M. Berner; A. J. Westhuizen
Source:
Cereal research communications 2010 v.38 no.4 pp. 506-513
ISSN:
0133-3720
Subject:
2,5-dihydroxybenzoic acid; Diuraphis noxia; biosynthesis; caffeic acid; cultivars; defense mechanisms; ferulic acid; gallic acid; phenylalanine ammonia-lyase; wheat
Abstract:
... The Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), is notorious for causing severe yield losses in many of the wheat producing areas of the world. The phenylpropanoid pathway is involved in many plant defence mechanisms. Phenylalanine ammonia-lyase (PAL) is a key enzyme leading to biosynthesis of phenolic acids, some of which are involved in plant defence mechanisms. The effect of ...
DOI:
10.1556/CRC.38.2010.4.7

37. A fast method using a new hydrophilic–lipophilic balanced sorbent in combination with ultra-high performance liquid chromatography for quantification of significant bioactive metabolites in wines

Author:
Catarina L. Silva; Jorge Pereira; Van G. Wouter; Carme Giró; José S. Câmara
Source:
Talanta 2011 v.86 no. pp. 82-90
ISSN:
0039-9140
Subject:
2,5-dihydroxybenzoic acid; bioactive properties; cinnamic acid; composite polymers; detection limit; ferulic acid; gallic acid; hydrophilicity; kaempferol; metabolites; myricetin; p-coumaric acid; protocatechuic acid; provenance; quercetin; red wines; rutin; solid phase extraction; syringic acid; ultra-performance liquid chromatography; white wines; Azores; Canary Islands; Madeira Islands
Abstract:
... This manuscript describes the development and validation of an ultra-fast, efficient, and high throughput analytical method based on ultra-high performance liquid chromatography (UHPLC) equipped with a photodiode array (PDA) detection system, for the simultaneous analysis of fifteen bioactive metabolites: gallic acid, protocatechuic acid, (−)-catechin, gentisic acid, (−)-epicatechin, syringic acid ...
DOI:
10.1016/j.talanta.2011.08.007

38. Analytical determination and pharmacokinetics of major metabolites of carbasalate calcium in broilers following oral administration

Author:
WANG, X.; HUANG, L.-L.; CHEN, D.-M.; IHSAN, A.; YUAN, Z.-H.
Source:
Journal of veterinary pharmacology and therapeutics 2011 v.34 no.4 pp. 410-416
ISSN:
0140-7783
Subject:
2,5-dihydroxybenzoic acid; anti-inflammatory agents; aspirin; body weight; calcium; metabolites; oral administration; pharmacokinetics; salicylic acid
Abstract:
... Wang, X., Huang, L.-L., Chen, D.-M., Ihsan, A., Yuan, Z.-H. Analytical determination and pharmacokinetics of major metabolites of carbasalate calcium in broilers following oral administration. J. vet. Pharmacol. Therap.34, 410-416. As a newer anti-inflammatory agent, carbasalate calcium is used in various animal species. In this study, the pharmacokinetics of carbasalate calcium was investigated i ...
DOI:
10.1111/j.1365-2885.2010.01250.x
PubMed:
21091728

39. Antioxidant activities, total phenolics and HPLC analyses of the phenolic compounds of extracts from common Mediterranean plants

Author:
Taha M. Rababah; Khalil I. Ereifej; Ranya B. Esoh; Muhammad H. Al-u'datt; Mohammad A. Alrababah; W. Yang
Source:
Natural product research 2011 v.25 no.6 pp. 596-605
ISSN:
1478-6427
Subject:
2,2-diphenyl-1-picrylhydrazyl; 2,5-dihydroxybenzoic acid; Petroselinum crispum; Salvia officinalis; antioxidant activity; antioxidants; benzoic acid; caffeic acid; catechin; chlorogenic acid; correlation; epicatechin; gallic acid; high performance liquid chromatography; parsley; plant extracts; protocatechuic acid; sage; syringic acid; vanillic acid; Jordan
Abstract:
... In this study, the total phenolic amounts and antioxidant activities of plant extracts obtained from some common Mediterranean plant species collected from different places in Jordan were determined. The phenolic constituents of these extracts were also determined using HPLC. The total phenolic amounts ranged from 52.8 to 876.9 mg GAE per 100 g dry material. The antioxidant activities were evaluat ...
DOI:
10.1080/14786419.2010.488232

40. Chemical Constituents of Boea hygrometrica

Author:
Wei-Sheng FENG; Yuan-Jing LI; Xiao-Ke ZHENG; Yan-Zhi WANG; Fang-Yi SU
Source:
Chinese journal of natural medicines 2011 v.9 no.6 pp. 406-409
ISSN:
1875-5364
Subject:
2,5-dihydroxybenzoic acid; chemical composition; chromatography; ferulic acid; silica gel; spectral analysis
Abstract:
... AIM: To study the chemical constituents of Boea hygrometrica (Bunge.) R. Br. METHODS: The compounds were isolated and purified by Diaion HP-20, Toyopearl HW-40, silica gel column chromatography and the structures were identified on the basis of spectral data and physiochemical properties. RESULTS: Seven compounds were obtained and identified as 5,7,3′4′-tetrahydroxy-6-methoxy-8-C-[β-D-xylopyranosy ...
DOI:
10.3724/SP.J.1009.2011.00406

41. High throughput quantitative analysis of melamine and triazines by MALDI-TOF MS

Author:
Ajeet Singh; Venkateswarlu Panchagnula
Source:
Analytical methods 2011 v.3 no.10 pp. 2360-2366
ISSN:
1759-9679
Subject:
2,5-dihydroxybenzoic acid; adulterants; detection limit; electrospray ionization mass spectrometry; liquid chromatography; melamine; milk; quantitative analysis; rapid methods
Abstract:
... Quantitative and high throughput MALDI MS analysis of symmetrical triazines (s-triazines), and milk contaminated with melamine has been demonstrated. s-Triazines from a multi component aqueous test mixture, and melamine, a known adulterant in milk, were quantified at low parts-per-million (ppm) level using 2,5-dihydroxybenzoic acid (2,5-DHB) as a matrix. Mass spectral peak intensity ratios of the ...
DOI:
10.1039/c1ay05262d

42. Identification and quantification of phenolic compounds from Balanites aegyptiaca (L) Del (Balanitaceae) galls and leaves by HPLC–MS

Author:
R.N.T. Meda; L. Vlase; A. Lamien-Meda; C.E. Lamien; D. Muntean; B. Tiperciuc; I. Oniga; O.G. Nacoulma
Source:
Natural product research 2011 v.25 no.2 pp. 93-99
ISSN:
1478-6427
Subject:
Balanites aegyptiacus; polyphenols; quercitrin; rutin; caffeic acid; isoquercitrin; kaempferol; 2,5-dihydroxybenzoic acid; sinapic acid; high performance liquid chromatography; mass spectrometry; p-coumaric acid; acid hydrolysis; galls; screening; ferulic acid; leaves
Abstract:
... Balanites aegyptiaca is a tropical plant which is widely used for medicinal purposes in several African countries, including Burkina Faso. Despite its widespread use, little is known about its phenolic content. This study sought to carry out a screening of the polyphenols from the leaves and galls of B. aegyptiaca. A high-performance liquid chromatography–mass spectrometry method was used to inves ...
DOI:
10.1080/14786419.2010.482933

43. Isoliquiritigenin (4,2′,4′-trihydroxychalcone): A new matrix-assisted laser desorption/ionization matrix with outstanding properties for the analysis of neutral oligosaccharides

Author:
Hongmei Yang; Jianwei Wang; Fengrui Song; Yihan Zhou; Shuying Liu
Source:
Analytica chimica acta 2011 v.701 no.1 pp. 45-51
ISSN:
0003-2670
Subject:
2,5-dihydroxybenzoic acid; chalcone; crystallization; desorption; ionization; matrix-assisted laser desorption-ionization mass spectrometry; oligosaccharides; quantitative analysis; salt tolerance
Abstract:
... A novel matrix of isoliquiritigenin (ISL), a flavonoid with a chalcone structure (4,2′,4′-trihydroxychalcone), was demonstrated to be advantageous in the analysis of neutral oligosaccharides by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). With ISL as a matrix, adequate signal for an analyte can be obtained in much lower matrix concentrations and lase ...
DOI:
10.1016/j.aca.2011.05.051

44. Polyphenols of Pseudostem of Different Banana Cultivars and Their Antioxidant Activities

Author:
Saravanan, K.; Aradhya, S.M.
Source:
Journal of agricultural and food chemistry 2011 v.59 no.8 pp. 3613–3623
ISSN:
0021-8561
Subject:
2,5-dihydroxybenzoic acid; antioxidant activity; bananas; caffeic acid; cinnamic acid; cultivars; ferulic acid; flavonoids; gallic acid; high performance liquid chromatography; methanol; polyphenols; protocatechuic acid; wastes
Abstract:
... The present investigation is focused on potential use of banana pseudostem (BPS), which otherwise is disposed off as a waste or incinerated, as a source of polyphenols or antioxidants. The total phenolics (TP) and total flavonoids (TF) in various solvent extracts of pseudostem (PS) of different banana cultivars varied from 7.58 to 291 mg gallic acid equivalent (GAE/g of extract) and from 4 to 80 m ...
DOI:
10.1021/jf103835z
PubMed:
21405133

45. Rapid analysis of fructans and comparison of fructan profiles in several different types of asparagus storage roots using MALDI-TOF MS

Author:
Takashi Suzuki; Tomoo Maeda; Shuko Nomura; Masahiko Suzuki; Gordon Grant; Peter Sporns
Source:
Journal of horticultural science & biotechnology 2011 v.86 no.3 pp. 210-216
ISSN:
2380-4084
Subject:
2,5-dihydroxybenzoic acid; biotechnology; carbohydrate metabolism; color; desorption; freeze drying; fructans; gamma-cyclodextrin; horticulture; ionization; matrix-assisted laser desorption-ionization mass spectrometry; polymerization; powders; rapid methods; roots
Abstract:
... Appropriate conditions for analysing fructans in the storage roots of field-grown asparagus using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) were investigated. High resolution and ionisation were achieved when lyophilised and ground storage root powders were extracted twice with 1.0 ml distilled and deionised hot water (90°C), supplemented with 1.0 ...
DOI:
10.1080/14620316.2011.11512749

46. Simultaneous analysis of acetaminophen, p‐aminophenol and aspirin metabolites by hydrophilic interaction and strong anion exchange capillary liquid chromatography coupled to amperometric detection

Author:
Minmin Zheng; Yimin Wu; Lanxiang Lu; Kang Ding; Fengxiang Tang; Zian Lin; Xiaoping Wu
Source:
Journal of separation science 2011 v.34 no.16‐17 pp. 2072-2078
ISSN:
1615-9306
Subject:
2,5-dihydroxybenzoic acid; acetaminophen; anion exchange; aspirin; detection limit; hydrophilic interactions; liquid chromatography; metabolites; pharmacokinetics; salicylic acid
Abstract:
... A simple and sensitive method has been developed for the simultaneous determination of polar nonsteroidal pharmaceuticals and metabolites, including acetaminophen, p‐aminophenol and several aspirin metabolites (salicylic acid, gentisic acid, salicyluric acid and 2,3‐dihydroxybenzoic acid), by capillary liquid chromatography with amperometric detection. Using a capillary monolithic column with mixe ...
DOI:
10.1002/jssc.201100163
PubMed:
21644253

47. Structural variability of endotoxins from R-type isogenic mutants of Shigella sonnei

Author:
Kilár, Anikó; Dörnyei, Ágnes; Bui, Annamária; Szabó, Zoltán; Kocsis, Béla; Kilár, Ferenc
Source:
Journal of mass spectrometry 2011 v.46 no.1 pp. 61-70
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; Shigella sonnei; biosynthesis; citric acid; desorption; endotoxins; fatty acid composition; hexoses; ionization; lipid A; matrix-assisted laser desorption-ionization mass spectrometry; mutants; oligosaccharides; sampling
Abstract:
... The structural variations in the rough-type endotoxins [lipopolysaccharides (LPSs)] of Shigella sonnei mutant strains (S. sonnei phase II--4303, R41, 562H and 4350) were investigated by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and tandem MS. A series of S. sonnei mutants had previously been the subject of analytical studies on the biosynthesis of ...
DOI:
10.1002/jms.1863

48. Structure and Function of the Oxidation Products of Polyphenols and Identification of Potent Lipoxygenase Inhibitors from Fe-Catalyzed Oxidation of Resveratrol

Author:
Shingai, Yoshimi; Fujimoto, Aya; Nakamura, Mitsuhiro; Masuda, Toshiya
Source:
Journal of agricultural and food chemistry 2011 v.59 no.15 pp. 8180-8186
ISSN:
0021-8561
Subject:
epicatechin; polyphenols; nordihydroguaiaretic acid; taxifolin; protocatechuic acid; alpha-tocopherol; rosmarinic acid; chlorogenic acid; syringic acid; iron; oxidation; gallic acid; linoleate 13S-lipoxygenase; sinapic acid; ellagic acid; resveratrol; catechin; quercetin; caffeic acid; propyl gallate; 2,5-dihydroxybenzoic acid; physicochemical properties; active ingredients
Abstract:
... Polyphenols have recently attracted much attention as potent antioxidants and related bioactive substances. These potent antioxidative polyphenols are very oxidizable due to their chemical properties, and their oxidation products must accumulate in the oxidizing foods when they are contained as the active ingredients. In this investigation, 30 polyphenols and related phenolics were oxidized with o ...
DOI:
10.1021/jf202561p
PubMed:
21726087

49. Tagging saccharides for signal enhancement in mass spectrometric analysis

Author:
Chang, Yu-Ling; Liao, Sylvain Kuo-Shiang; Chen, Ying-Chu; Hung, Wei-Ting; Yu, Hui-Ming; Yang, Wen-Bin; Fang, Jim-Min; Chen, Chung-Hsuan; Lee, Yuan Chuan
Source:
Journal of mass spectrometry 2011 v.46 no.3 pp. 247-255
ISSN:
1076-5174
Subject:
2,5-dihydroxybenzoic acid; aldoses; arginine; bradykinin; detection limit; hydrophilicity; hydrophobicity; ionization; matrix-assisted laser desorption-ionization mass spectrometry; nucleic acids; oligosaccharides; phenylalanine; polysaccharides; proteins; synergism
Abstract:
... MALDI-MS provides a rapid and sensitive analysis of large biomolecules such as proteins and nucleic acids. However, oligo- and polysaccharides are less sensitive in MS analysis partly due to their neutral and hydrophilic nature to cause low ionization efficiency. In this study, four types of oligosaccharides including aldoses, aminoaldoses, alduronic acids and α-keto acids were modified by appropr ...
DOI:
10.1002/jms.1887

50. A novel matrix additive, MCM-41-type mesoporous silica nanoparticles, used for analysis of peptides by MALDI-FT/ICRMS

Author:
Chen Jun; He Tianxi; Fan Xuemei
Source:
Talanta 2012 v.100 no. pp. 419-424
ISSN:
0039-9140
Subject:
2,5-dihydroxybenzoic acid; angiotensin II; bradykinin; corticotropin; desorption; ionization; ions; mass spectrometry; molecular weight; nanoparticles; polypeptides; silica
Abstract:
... Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was thought to be unsuitable for the analysis of low-molecular-weight species since matrix peak noise made it difficult to identify analyte ions. In this study, MCM-41-type mesoporous silica nanoparticles (MSNs) were used as a matrix additive with saturated 2,5-dihydroxybenzoic acid (DHB) or α-cyano-4-hydroxycinnannic acid (C ...
DOI:
10.1016/j.talanta.2012.08.011