Base de dados : MEDLINE
Pesquisa : G02.111.570.685 [Categoria DeCS]
Referências encontradas : 19121 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 1913 ir para página                         

  1 / 19121 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29279438
[Au] Autor:Ebitani M; Ebitani T
[Ad] Endereço:Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University.
[Ti] Título:[Rotational Isomers of Diphenhydramine].
[So] Source:Yakugaku Zasshi;138(3):417-424, 2018 Mar 01.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo: Diphenhydramine (DP), an antihistaminic agent, may become colored and daker or more fluorescent during storage. Herein, we spectroscopically examined the causes of this phenomenon under various DP storage conditions and durations. The infrared vibration-rotation spectrum shows multiple Gauche (G)-type conformers with different intramolecular n→π interaction strengths. The splitting pattern of the dimethylamino group protons in the H-NMR spectrum indicates that DP is mainly in the G-type with a small portion in the Trans (T)-type. The correlation between the red-shifted peak intensity in the UV•VIS absorbance spectrum and the coloring progression indicates a decreased intramolecular n→π interaction of the G-type under elevated temperature during storage. Enhanced fluorescence detected in the Excitation•Fluorescence spectrum demonstrates G-type (quenching) to T-type (fluorescent) conformation conversion, which is due to activated internal rotation of the dimethylamino group under elevated storage temperature and electronic excitation in the phenyl groups under light irradiation during storage. A signal detected in the ESR spectrum corresponds to the G-type charge transfer (CT) structure wherein part of the nonbonding electron pair on the N atom is intramolecularly redistributed to the phenyl groups. The CT structure presents the G-type quenching characteristics, whereas weak CT bonding corresponds to coloring. The results indicate that the quenching G-type is converted to T-type by heat or light to become color faded and bright with enhanced fluorescence and that T-type is reverted to G-type after storage under cool and dark conditions or by vacuum distillation to lose fluorescence.
[Mh] Termos MeSH primário: Difenidramina/química
Estabilidade de Medicamentos
Armazenamento de Medicamentos
Antagonistas dos Receptores Histamínicos/química
[Mh] Termos MeSH secundário: Cor
Espectroscopia de Ressonância de Spin Eletrônica
Fluorescência
Isomerismo
Luz
Espectroscopia de Ressonância Magnética
Conformação Molecular
Rotação
Espectrometria de Fluorescência
Espectrofotometria Infravermelho
Análise Espectral
Temperatura Ambiente
Vibração
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Histamine Antagonists); 8GTS82S83M (Diphenhydramine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171228
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.17-00175


  2 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29413581
[Au] Autor:Thaxton-Weissenfluh A; Alsegiani AS; Abiedalla Y; DeRuiter J; Smith F; Clark CR
[Ad] Endereço:Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA.
[Ti] Título:Analytical studies on the 2-naphthoyl substituted-1-n-pentylindoles: Regioisomeric synthetic cannabinoids.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1077-1078:77-84, 2018 Mar 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The six 1-n-pentyl-2-, 3-, 4-, 5-, 6- and 7-(2-naphthoyl)-indoles each have the same substituents attached to the indole ring, identical elemental composition (C H NO) yielding identical nominal and accurate masses. The electron ionization mass spectra of the 2-naphthoyl substituted isomers share equivalent major fragment ions resulting from cleavage of the groups attached to the central indole nucleus with some differences in relative abundances. These six regioisomers were successfully resolved on an Rtx-5 and Rxi-17Sil MS stationary phases and the molecules having both substituent groups on the same side of the indole ring (1,2- and 1,7-substituents) show the least retention. The more linear molecules have higher relative retention properties. A comparison of the GC properties of the 1-naphthoyl- and 2-naphthoyl groups attached at identical positions of the indole ring showed higher GC retention for the 2-naphthoyl substituted isomer in all cases evaluated. The amide inverse isomers (1-naphthoyl-3-n-pentylindoles) were separated from the 1-n-pentyl-3-naphthoyl-indoles on an Rtx-200 stationary phase. The two inverse amide isomers having the 1- and 2-naphthoyl groups substituted at the 1-position of the indole ring elute before either of the N-alkyl-indole isomers having the 1- and 2-naphthoyl groups substituted at the 3-position of the indole ring. The amide inverse isomers yield EI mass spectra easily distinguishing these amides from the ketone isomers having the naphthoyl groups at the indole 3-position.
[Mh] Termos MeSH primário: Canabinoides/análise
Canabinoides/química
Indóis/análise
Indóis/química
Naftalenos/análise
Naftalenos/química
[Mh] Termos MeSH secundário: Cromatografia Gasosa-Espectrometria de Massas
Isomerismo
Modelos Moleculares
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (1-pentyl-3-(1-naphthoyl)indole); 0 (Cannabinoids); 0 (Indoles); 0 (Naphthalenes)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180208
[St] Status:MEDLINE


  3 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29335413
[Au] Autor:Abberley JP; Killah R; Walker R; Storey JMD; Imrie CT; Salamonczyk M; Zhu C; Gorecka E; Pociecha D
[Ad] Endereço:Department of Chemistry, King's College, University of Aberdeen, Aberdeen, AB24 3UE, UK.
[Ti] Título:Heliconical smectic phases formed by achiral molecules.
[So] Source:Nat Commun;9(1):228, 2018 01 15.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chiral symmetry breaking in soft matter is a hot topic of current research. Recently, such a phenomenon was found in a fluidic phase showing orientational order of molecules-the nematic phase; although built of achiral molecules, the phase can exhibit structural chirality-average molecular direction follows a short-pitch helix. Here, we report a series of achiral asymmetric dimers with an odd number of atoms in the spacer, which form twisted structures in nematic as well as in lamellar phases. The tight pitch heliconical nematic (N ) phase and heliconical tilted smectic C (SmC ) phase are formed. The formation of a variety of helical structures is accompanied by a gradual freezing of molecular rotation. In the lowest temperature smectic phase, HexI, the twist is expressed through the formation of hierarchical structure: nanoscale helices and mesoscopic helical filaments. The short-pitch helical structure in the smectic phases is confirmed by resonant X-ray measurements.
[Mh] Termos MeSH primário: Cristais Líquidos/química
Conformação Molecular
Nanoestruturas/química
Transição de Fase
[Mh] Termos MeSH secundário: Dicroísmo Circular
Isomerismo
Microscopia de Força Atômica
Modelos Químicos
Modelos Moleculares
Estrutura Molecular
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02626-6


  4 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29300475
[Au] Autor:Zou D; Zhu X; Zhang F; Du Y; Ma J; Jiang R
[Ad] Endereço:Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University , Guangzhou 510632, P. R. China.
[Ti] Título:An Efficient Strategy Based on Liquid-Liquid Extraction with Three-Phase Solvent System and High Speed Counter-Current Chromatography for Rapid Enrichment and Separation of Epimers of Minor Bufadienolide from Toad Meat.
[So] Source:J Agric Food Chem;66(4):1008-1014, 2018 Jan 31.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This study presents an efficient strategy based on liquid-liquid extraction with three-phase solvent system and high speed counter-current chromatography for rapid enrichment and separation of epimers of minor bufadienolide from toad meat. The reflux extraction conditions were optimized by response surface methodology first, and a novel three-phase solvent system composed of n-hexane/methyl acetate/acetonitrile/water (3:6:5:5, v/v) was developed for liquid-liquid extraction of the crude extract. This integrative extraction process could enrich minor bufadienolide from complex matrix efficiently and minimize the loss of minor targets induced by repeated extraction with different kinds of organic solvents occurring in the classical liquid two-phase extraction. As a result, four epimers of minor bufadienolide were greatly enriched in the middle phase and total content of these epimers of minor bufadienolide was increased from 3.25% to 46.23%. Then, the enriched four epimers were separated by HSCCC with a two-phase solvent system composed of chloroform/methanol/water (4:2:2, v/v) successfully. Furthermore, we tested Na ,K -ATPase (NKA) inhibitory effect of the four epimers. 3ß-Isomers of bufadienolide showed stronger (>8-fold) inhibitory activity than 3α-isomers. The characterization of minor bufadienolide in toad meat and their significant difference of inhibitory effect on NKA would promote the further quantitative analysis and safety evaluation of toad meat as a food source.
[Mh] Termos MeSH primário: Bufanolídeos/química
Bufanolídeos/isolamento & purificação
Bufonidae
Distribuição Contracorrente/métodos
Extração Líquido-Líquido/métodos
Carne/análise
[Mh] Termos MeSH secundário: Animais
Bufanolídeos/farmacologia
Inibidores Enzimáticos
Isomerismo
ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores
Solventes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bufanolides); 0 (Enzyme Inhibitors); 0 (Solvents); 29565-35-3 (bufadienolide); EC 3.6.1.- (ATP1A1 protein, human); EC 3.6.3.9 (Sodium-Potassium-Exchanging ATPase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180105
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b05310


  5 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28749499
[Au] Autor:Horbury MD; Quan WD; Flourat AL; Allais F; Stavros VG
[Ad] Endereço:Department of Chemistry, University of Warwick, Gibbet Hill, Coventry, CV4 7AL, UK. v.stavros@warwick.ac.uk.
[Ti] Título:Elucidating nuclear motions in a plant sunscreen during photoisomerization through solvent viscosity effects.
[So] Source:Phys Chem Chem Phys;19(31):21127-21131, 2017 Aug 09.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We explore the effects of solvent viscosity on the trans-cis photoisomerization of sinapoyl malate, which is utilized as a sunscreen molecule in plants. Our results demonstrate that viscosity has a significant effect on the timescale for isomerization, providing insight into the nuclear motions involved. The ramifications of these findings are discussed with reference to sinapoyl malate's in vivo photoprotection properties.
[Mh] Termos MeSH primário: Malatos/química
Fenilpropionatos/química
Plantas/química
Solventes/química
Protetores Solares/química
[Mh] Termos MeSH secundário: Isomerismo
Plantas/metabolismo
Espectrofotometria
Raios Ultravioleta
Viscosidade/efeitos da radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2-O-sinapoylmalate); 0 (Malates); 0 (Phenylpropionates); 0 (Solvents); 0 (Sunscreening Agents)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp04070a


  6 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28923343
[Au] Autor:Liu HS; Wen LL; Chu PL; Lin CY
[Ad] Endereço:Department of Obstetrics and Gynaecology, Hsinchu Cathay General Hospital, Hsinchu 300, Taiwan.
[Ti] Título:Association among total serum isomers of perfluorinated chemicals, glucose homeostasis, lipid profiles, serum protein and metabolic syndrome in adults: NHANES, 2013-2014.
[So] Source:Environ Pollut;232:73-79, 2018 Jan.
[Is] ISSN:1873-6424
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Perfluorinated chemicals (PFCs) have been used widely in consumer products manufacture. Recent in vitro as well as animal studies have found that there are different toxicity and pharmacokinetic profiles between isomers of perfluorooctanoic acid (PFOA) and/or perfluorooctane sulfonate (PFOS). However, the differential effects of linear or branched PFOA/PFOS isomers on human beings have never been reported. Herein, we examined 1871 adult subjects (age older than 18 years) from the National Health and Nutrition Examination Survey (NHANES) 2013-2014 to determine the association between the isomers of PFOA/PFOS and serum biochemistry profiles, including glucose, lipids, protein and components of metabolic syndrome (MS). The results showed that for PFOA, increased linear PFOA was associated with increases in total cholesterol, serum albumin and an enhancement of ß cell function as well as a decrease in the serum globulin. Increased branched PFOA was significantly associated with increased fasting glucose. All isomers of PFOA were positively associated with high-density lipoprotein-cholesterol (HDL-C) and negatively associated with glycohemoglobin (HbA1C). The branched PFOS was positively associated with ß cell function and inversely associated with serum globulin. Both linear and branched isomers of PFOS were positively associated with the total protein and albumin. The increased branched PFOA was associated with less HDL-C insufficiency defined by the National Cholesterol Education Program Third Adult Treatment Panel (NCEP-ATP III) MS criteria, whereas the increased concentrations of serum total and linear PFOS were associated with less hypertriglyceridemia by the NCEP-ATP III. In conclusion, serum isomers of PFOA and PFOS were associated with glucose homeostasis, serum protein as well as lipid profiles; they were also indicators of MS. This may suggest that there is a distinct difference in the toxicokinetics of the isomers of PFOA and PFOS. Further clinical and animal studies are warranted to clarify the putative causal relationships between isomers and biochemical alterations.
[Mh] Termos MeSH primário: Exposição Ambiental/estatística & dados numéricos
Poluentes Ambientais/sangue
Fluorcarbonetos/sangue
Síndrome Metabólica/sangue
Inquéritos Nutricionais
[Mh] Termos MeSH secundário: Adulto
Ácidos Alcanossulfônicos
Animais
Proteínas Sanguíneas
Caprilatos
Colesterol
Feminino
Glucose
Homeostase
Seres Humanos
Isomerismo
Lipídeos/sangue
Masculino
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkanesulfonic Acids); 0 (Blood Proteins); 0 (Caprylates); 0 (Environmental Pollutants); 0 (Fluorocarbons); 0 (Lipids); 947VD76D3L (perfluorooctanoic acid); 97C5T2UQ7J (Cholesterol); 9H2MAI21CL (perfluorooctane sulfonic acid); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170920
[St] Status:MEDLINE


  7 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29199220
[Au] Autor:Kohiki T; Nishikawa Y; Inokuma T; Shigenaga A; Otaka A
[Ad] Endereço:Institute of Biomedical Sciences and Graduate School of Pharmaceutical Sciences, Tokushima University.
[Ti] Título:Chemical Synthetic Platform for Chlorpromazine Oligomers That Were Reported as Photo-degradation Products of Chlorpromazine.
[So] Source:Chem Pharm Bull (Tokyo);65(12):1161-1166, 2017.
[Is] ISSN:1347-5223
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:A synthetic platform for chlorpromazine (CPZ) oligomers, which could be generated via photo-reaction of CPZ, is essential to promote their biological and structural studies. In this paper, the first synthetic platform for CPZ oligomers is described. A photo-irradiation experiment of CPZ to confirm whether the structure of the CPZ dimer generated by the photo-irradiation was identical to that prepared by our synthetic method is also reported.
[Mh] Termos MeSH primário: Clorpromazina/química
[Mh] Termos MeSH secundário: Clorpromazina/síntese química
Cromatografia Líquida de Alta Pressão
Dimerização
Isomerismo
Espectrometria de Massas
Fotólise/efeitos da radiação
Polimerização/efeitos da radiação
Raios Ultravioleta
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
U42B7VYA4P (Chlorpromazine)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180110
[Lr] Data última revisão:
180110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.1248/cpb.c17-00692


  8 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:29190818
[Au] Autor:Cortes-Hernandez P; Domínguez-Ramírez L
[Ad] Endereço:Centro de Investigacion Biomedica de Oriente (CIBIOR), Instituto Mexicano del Seguro Social (IMSS), Metepec, Puebla, Mexico.
[Ti] Título:Role of cis-trans proline isomerization in the function of pathogenic enterobacterial Periplasmic Binding Proteins.
[So] Source:PLoS One;12(11):e0188935, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Periplasmic Binding Proteins (PBPs) trap nutrients for their internalization into bacteria by ABC transporters. Ligand binding triggers PBP closure by bringing its two domains together like a Venus flytrap. The atomic determinants that control PBP opening and closure for nutrient capture and release are not known, although it is proposed that opening and ligand release occur while in contact with the ABC transporter for concurrent substrate translocation. In this paper we evaluated the effect of the isomerization of a conserved proline, located near the binding site, on the propensity of PBPs to open and close. ArgT/LAO from Salmonella typhimurium and HisJ from Escherichia coli were studied through molecular mechanics at two different temperatures: 300 and 323 K. Eight microseconds were simulated per protein to analyze protein opening and closure in the absence of the ABC transporter. We show that when the studied proline is in trans, closed empty LAO and HisJ can open. In contrast, with the proline in cis, opening transitions were much less frequent and characterized by smaller changes. The proline in trans also renders the open trap prone to close over a ligand. Our data suggest that the isomerization of this conserved proline modulates the PBP mechanism: the proline in trans allows the exploration of conformational space to produce trap opening and closure, while in cis it restricts PBP movement and could limit ligand release until in productive contact with the ABC transporter. This is the first time that a proline isomerization has been related to the control of a large conformational change like the PBP flytrap mechanism.
[Mh] Termos MeSH primário: Enterobacteriaceae/metabolismo
Proteínas Periplásmicas de Ligação/metabolismo
Prolina/metabolismo
[Mh] Termos MeSH secundário: Isomerismo
Prolina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Periplasmic Binding Proteins); 9DLQ4CIU6V (Proline)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180101
[Lr] Data última revisão:
180101
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171201
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188935


  9 / 19121 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28455341
[Au] Autor:Garby TJ; Matys ED; Ongley SE; Salih A; Larkum AWD; Walter MR; Summons RE; Neilan BA
[Ad] Endereço:Australian Centre for Astrobiology and School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia.
[Ti] Título:Lack of Methylated Hopanoids Renders the Cyanobacterium Nostoc punctiforme Sensitive to Osmotic and pH Stress.
[So] Source:Appl Environ Microbiol;83(13), 2017 Jul 01.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:To investigate the function of 2-methylhopanoids in modern cyanobacteria, the gene coding for the radical -adenosyl methionine (SAM) methylase protein that acts on the C-2 position of hopanoids was deleted from the filamentous cyanobacterium ATCC 29133S. The resulting Δ mutant lacked all 2-methylhopanoids but was found to produce much higher levels of two bacteriohopanepentol isomers than the wild type. Growth rates of the Δ mutant cultures were not significantly different from those of the wild type under standard growth conditions. Akinete formation was also not impeded by the absence of 2-methylhopanoids. The relative abundances of the different hopanoid structures in akinete-dominated cultures of the wild-type and Δ mutant strains were similar to those of vegetative cell-dominated cultures. However, the Δ mutant was found to have decreased growth rates under both pH and osmotic stress, confirming a role for 2-methylhopanoids in stress tolerance. Evidence of elevated photosystem II yield and NAD(P)H-dependent oxidoreductase activity in the Δ mutant under stress conditions, compared to the wild type, suggested that the absence of 2-methylhopanoids increases cellular metabolic rates under stress conditions. As the first group of organisms to develop oxygenic photosynthesis, are central to the evolutionary history of life on Earth and the subsequent oxygenation of the atmosphere. To investigate the origin of cyanobacteria and the emergence of oxygenic photosynthesis, geobiologists use biomarkers, the remnants of lipids produced by different organisms that are found in geologic sediments. 2-Methylhopanes have been considered indicative of cyanobacteria in some environmental settings, with the parent lipids 2-methylhopanoids being present in many contemporary cyanobacteria. We have created a Δ mutant strain that does not produce 2-methylhopanoids to assess the influence of 2-methylhopanoids on stress tolerance. Increased metabolic activity in the mutant under stress indicates compensatory alterations in metabolism in the absence of 2-methylhopanoids.
[Mh] Termos MeSH primário: Nostoc/metabolismo
Triterpenos/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Concentração de Íons de Hidrogênio
Isomerismo
Metilação
Nostoc/química
Nostoc/genética
Nostoc/crescimento & desenvolvimento
Osmose
Triterpenos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Triterpenes)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171225
[Lr] Data última revisão:
171225
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170430
[St] Status:MEDLINE


  10 / 19121 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28873614
[Au] Autor:He F; Qian YL; Qian MC
[Ad] Endereço:Department of Food Science and Technology, Oregon State University, Corvallis, OR 97331, United States.
[Ti] Título:Flavor and chiral stability of lemon-flavored hard tea during storage.
[So] Source:Food Chem;239:622-630, 2018 Jan 15.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Flavor stability of hard tea beverage was investigated over eight weeks of storage. The volatile compounds were analyzed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and two-dimensional GC-MS. Quantitative analysis showed that the concentrations of linalool, citronellol, geranial, neral, geraniol, and nerol decreased dramatically during storage, whereas α-terpineol showed an increasing trend during storage. Heart-cut two-dimensional GC-MS (2D-GC-MS) chirality analysis showed that (R)-(+)-limonene, (R)-(-)-linalool, (S)-(-)-α-terpineol and (S)-(-)-4-terpineol dominated in the fresh hard tea samples, however, the configuration changed during storage for the terpene alcohols. The storage conditions did not change the configuration of limonene. A conversion of (R)-(-)-linalool to (S)-(+) form was observed during storage. Both (S)-α-terpineol and (S)-4-terpineol dominated at beginning of the storage, but (R)-(+)-α-terpineol became dominated after storage, suggested in addition to isomerization from (S)-α-terpineol, other precursors could also generate α-terpineol with (R)-isomer preference.
[Mh] Termos MeSH primário: Chá
[Mh] Termos MeSH secundário: Cicloexenos
Aromatizantes
Cromatografia Gasosa-Espectrometria de Massas
Isomerismo
Monoterpenos
Terpenos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyclohexenes); 0 (Flavoring Agents); 0 (Monoterpenes); 0 (Tea); 0 (Terpenes); 21334LVV8W (alpha-terpineol); 9MC3I34447 (limonene)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170907
[St] Status:MEDLINE



página 1 de 1913 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde