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  1 / 17272 MEDLINE  
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[PMID]:29367490
[Au] Autor:Asakawa T; Takano Y; Ohta A; Asakawa H
[Ad] Endereço:School of Chemistry, College of Science and Engineering, Kanazawa University.
[Ti] Título:Aggregation and pH Responsive Behavior of Thioester Surfactants and Formation of Disulfide Linkages in Aqueous Solutions.
[So] Source:J Oleo Sci;67(2):199-206, 2018 Feb 01.
[Is] ISSN:1347-3352
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:pH responsive surfactants, [C H N(CH ) (CH ) SCOCH ]Br (C nSAc, n = 4, 11, 12), were prepared, and their properties in aqueous solution were examined. The critical micelle concentration (cmc) and critical vesicle concentration (cvc) were determined based on changes in conductivity, as well as by fluorescence measurements, and light scattering methods. A significant increase in the light scattering intensities of the C nSAc (n=11, 12) systems suggested that the growth of aggregates was accompanied by considerable counterion binding with increasing surfactant concentration. The diameter of C 11SAc, recorded by the dynamic light scattering measurements, was about 9.6 ±1.0 nm, which was slightly smaller than that for didodecyldimethylammonium bromide (DDAB) vesicles. The thioester group was easily hydrolyzed upon the addition of NaOH, while it was hardly hydrolyzed with the addition of HCl. The time course of alkaline hydrolysis was examined by the conductivity measurements and high-performance liquid chromatography analysis. [C H N(CH ) (CH ) SS(CH ) N(CH ) C H ]2Br (2C 11SS) was generated in the C 11SAc alkaline solution because of air oxidation. The C 11SAc alkaline solution gradually became an opaque blue color with increasing light scattering at 346 nm, indicating the remarkable growth of vesicles. The chemical structure of 2C 11SS was consistent with that of a disulfide linked double tailed surfactant, similar to DDAB. The disulfide linkage between the double tailed surfactants will contribute to the stabilization and growth of vesicles.
[Mh] Termos MeSH primário: Ésteres/química
Tensoativos/química
Água/química
[Mh] Termos MeSH secundário: Dissulfetos/química
Difusão Dinâmica da Luz
Concentração de Íons de Hidrogênio
Hidrólise
Micelas
Oxirredução
Compostos de Amônio Quaternário/química
Soluções
Tensão Superficial
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Disulfides); 0 (Esters); 0 (Micelles); 0 (Quaternary Ammonium Compounds); 0 (Solutions); 0 (Surface-Active Agents); 059QF0KO0R (Water); 13146-86-6 (didodecyldimethylammonium)
[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:180126
[St] Status:MEDLINE
[do] DOI:10.5650/jos.ess17192


  2 / 17272 MEDLINE  
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[PMID]:29367483
[Au] Autor:Matsuura T; Ogawa A; Ohara Y; Nishina S; Nakanishi M; Gohtani S
[Ad] Endereço:Department of Applied Biological Science, Kagawa University.
[Ti] Título:Effect of Alcohols on the Phase Behavior and Emulsification of a Sucrose Fatty Acid Ester/Water/Edible Oil System.
[So] Source:J Oleo Sci;67(2):167-176, 2018 Feb 01.
[Is] ISSN:1347-3352
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The effect of alcohols (ethanol, 1-propanol, propylene glycol, glycerin, sucrose) on the phase behavior and emulsification of sucrose stearic acid ester (SSE)/water/edible vegetable oil (EVO) systems was investigated. Adding sucrose, propylene glycol, and glycerin narrowed the oil-separated two-phase region in the phase diagram of the SSE/water/EVO systems, whereas adding ethanol and 1-propanol expanded the oil-separated two-phase region. Changing the course of emulsification in the phase diagram showed that the size of the oil-droplet particle typically decreased in a system with a narrowed oil-separated region. The emulsification properties of the systems varied with respect to changes in the phase diagram. The microstructure of the systems was examined using small-angle X-ray scattering, and the ability to retain the oil in the lamellar structure of the SSEs was suggested as an important role in emulsification, because the mechanism of the systems was the same as that for the liquid crystal emulsification method.
[Mh] Termos MeSH primário: Álcoois/química
Ésteres/química
Ácidos Graxos/química
Transição de Fase
Óleos Vegetais/química
Ácidos Esteáricos/química
Sacarose/química
Água/química
[Mh] Termos MeSH secundário: Emulsões
Glicerol/química
Propilenoglicol/química
Espalhamento a Baixo Ângulo
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alcohols); 0 (Emulsions); 0 (Esters); 0 (Fatty Acids); 0 (Plant Oils); 0 (Stearic Acids); 059QF0KO0R (Water); 4ELV7Z65AP (stearic acid); 57-50-1 (Sucrose); 6DC9Q167V3 (Propylene Glycol); PDC6A3C0OX (Glycerol)
[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:180126
[St] Status:MEDLINE
[do] DOI:10.5650/jos.ess17146


  3 / 17272 MEDLINE  
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[PMID]:29442036
[Au] Autor:Pivodová V; Zahler S; Karas D; Valentová K; Ulrichova J
[Ti] Título: study of 2,3-dehydrosilybin and its galloyl esters as potential inhibitors of angiogenesis.
[So] Source:Pharmazie;71(8):478-483, 2016 08 01.
[Is] ISSN:0031-7144
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:2,3-Dehydrosilybin exhibits substantial anticancer and antiangiogenic effects, which can be potentially improved by semi-synthetic modification such as esterification with gallic acid. The aim of this study was to examine the potential antiangiogenic effect of 2,3-dehydrosilybin and its galloyl esters (3-O-galloyl-2,3-dehydrosilybin; 7-O-galloyl-2,3-dehydrosilybin; 20-O-galloyl-2,3-dehydrosilybin and 23-O-galloyl-2,3-dehydrosilybin) and to determine which molecular mechanism could be responsible for their activity. The effect on cell proliferation, tube formation, signal transduction pathways (PI3K/Akt and ERK) and the cell cycle was studied in human microvascular endothelial cells (HMEC). The results showed that all compounds decreased the growth of HMEC, but the strongest effect was observed for 20-O-galloyl-2,3-dehydrosilybin at 5 µmol/l. In addition, at 5 and 10 µmol/l, this was the only compound that significantly inhibited HMEC tube formation. Based on an assessment of Akt and ERK1/2 expression, we suggest that 20-O-galloyl-2,3-dehydrosilybin influences the angiogenic process through the Akt pathway.
[Mh] Termos MeSH primário: Inibidores da Angiogênese/farmacologia
Silimarina/farmacologia
[Mh] Termos MeSH secundário: Inibidores da Angiogênese/síntese química
Ciclo Celular/efeitos dos fármacos
Proliferação Celular/efeitos dos fármacos
Células Endoteliais/efeitos dos fármacos
Ésteres/síntese química
Ésteres/farmacologia
Ácido Gálico/síntese química
Ácido Gálico/farmacologia
Seres Humanos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos
Microtúbulos/efeitos dos fármacos
Neovascularização Patológica/tratamento farmacológico
Proteína Oncogênica v-akt/efeitos dos fármacos
Fosfatidilinositol 3-Quinases/efeitos dos fármacos
Silimarina/síntese química
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Angiogenesis Inhibitors); 0 (Esters); 0 (Silymarin); 4RKY41TBTF (silybin); 632XD903SP (Gallic Acid); EC 2.7.1.- (Phosphatidylinositol 3-Kinases); EC 2.7.11.1 (Oncogene Protein v-akt)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180215
[St] Status:MEDLINE
[do] DOI:10.1691/ph.2016.6579


  4 / 17272 MEDLINE  
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[PMID]:28610437
[Au] Autor:Song Y; Zhou J; Wang X; Xie X; Zhao Y; Ni F; Huang W; Wang Z; Xiao W
[Ad] Endereço:a Jiangsu Kanion Pharmaceutical Co., Ltd. , Lianyungang , People's Republic of China.
[Ti] Título:A new ferulic acid ester from Rhodiola wallichiana var. cholaensis (Crassulaceae).
[So] Source:Nat Prod Res;32(1):77-84, 2018 Jan.
[Is] ISSN:1478-6427
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A new ferulic acid ester, 6-feruloyloxyhexanoic acid (1), was isolated along with 10 known ones (2-11), from the concentrated water extract of Rhodiola wallichiana var. cholaensis. Their chemical structures were elucidated on the basis of extensive spectroscopic methods including Two-dimensional nuclear magnetic resonance (2D NMR) experiments. Compound 3 was isolated from this plant for the first time. The protective effects against H O -induced myocardial cell injury in cultured H9c2 cells were also evaluated. Compounds 1, 5 and 7-11 provided significant protective effects on H O -induced H9c2 cells injury at the concentration of 25 µg/mL. And the protective effects of compound 1 was also investigated by the oxygen-glucose deprivation/reperfusion (OGD/R) tests.
[Mh] Termos MeSH primário: Caproatos/farmacologia
Cardiotônicos/farmacologia
Ácidos Cumáricos/farmacologia
Rhodiola/química
[Mh] Termos MeSH secundário: Animais
Antioxidantes/química
Antioxidantes/farmacologia
Caproatos/administração & dosagem
Caproatos/química
Cardiotônicos/administração & dosagem
Cardiotônicos/química
Células Cultivadas
Ácidos Cumáricos/administração & dosagem
Ácidos Cumáricos/química
Relação Dose-Resposta a Droga
Ésteres/administração & dosagem
Ésteres/química
Ésteres/farmacologia
Peróxido de Hidrogênio/toxicidade
Espectroscopia de Ressonância Magnética
Estrutura Molecular
Miócitos Cardíacos/citologia
Miócitos Cardíacos/efeitos dos fármacos
Extratos Vegetais/química
Ratos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antioxidants); 0 (Caproates); 0 (Cardiotonic Agents); 0 (Coumaric Acids); 0 (Esters); 0 (Plant Extracts); BBX060AN9V (Hydrogen Peroxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170615
[St] Status:MEDLINE
[do] DOI:10.1080/14786419.2017.1335724


  5 / 17272 MEDLINE  
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[PMID]:29355013
[Au] Autor:Zhang W; Li X; Hua F; Chen W; Wang W; Chu GX; Bao GH
[Ad] Endereço:Natural Products Laboratory, International Joint Lab of Tea Chemistry and Health Effects, State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University , Hefei, 230036 People's Republic of China.
[Ti] Título:Interaction between Ester-Type Tea Catechins and Neutrophil Gelatinase-Associated Lipocalin: Inhibitory Mechanism.
[So] Source:J Agric Food Chem;66(5):1147-1156, 2018 Feb 07.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Tea is thought to alleviate neurotoxicity due to the antioxidative effect of ester-type tea catechins (ETC). Neutrophil gelatinase-associated lipocalin (NGAL) can sensitize ß-amyloid (Aß) induced neurotoxicity, and inhibitors of NGAL may relieve associated symptoms. As such, the interactions of ETC with NGAL were investigated by fluorescence spectrometry and molecular simulation. NGAL fluorescence is quenched regularly when being added with six processing types of tea infusion (SPTT) and ETC. Thermodynamic analyses suggest that ETC with more catechol moieties has a stronger binding capacity with NGAL especially in the presence of Fe . (-)-Epicatechin 3-O-caffeoate (ECC), a natural product isolated from Zijuan green tea, shows the strongest binding ability with NGAL (K = 15.21 ± 8.68 nM in the presence of Fe ). All ETC are effective in protecting nerve cells against H O or Aß induced injury. The inhibitory mechanism of ETC against NGAL supports its potential use in attenuation of neurotoxicity.
[Mh] Termos MeSH primário: Catequina/farmacologia
Lipocalina-2/farmacologia
Chá/química
[Mh] Termos MeSH secundário: Catequina/metabolismo
Interações Medicamentosas
Ésteres
Peróxido de Hidrogênio/farmacologia
Quelantes de Ferro
Lipocalina-2/antagonistas & inibidores
Lipocalina-2/metabolismo
Modelos Moleculares
Neurônios/efeitos dos fármacos
Fármacos Neuroprotetores
Espectrometria de Fluorescência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Esters); 0 (Iron Chelating Agents); 0 (Lipocalin-2); 0 (Neuroprotective Agents); 0 (Tea); 8R1V1STN48 (Catechin); BBX060AN9V (Hydrogen Peroxide)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180123
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b05399


  6 / 17272 MEDLINE  
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[PMID]:28748237
[Au] Autor:Suzuki J; Miyano N; Yashiro S; Umezawa T; Matsuda F
[Ad] Endereço:Graduate School of Environmental Science, Hokkaido University, N10 W5, Sapporo 060-0810, Japan. umezawa@ees.hokudai.ac.jp fmatsuda@ees.hokudai.ac.jp.
[Ti] Título:Total synthesis of (-)-kainic acid and (+)-allo-kainic acid through SmI -mediated intramolecular coupling between allyl chloride and an α,ß-unsaturated ester.
[So] Source:Org Biomol Chem;15(31):6557-6566, 2017 Aug 09.
[Is] ISSN:1477-0539
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A 3,4-disubstituted pyrrolidine ring was effectively cyclized through SmI -mediated reductive coupling between allyl chloride and an α,ß-unsaturated ester, although little has been reported about SmI -promoted C-C bond formation of an allyl chloride with an α,ß-unsaturated ester. Selection of either the 3,4-cis- or 3,4-trans-selective cyclization can be accomplished simply by changing the additives from NiI to HMPA during reductive cyclization conducted in H O-THF. Total synthesis of (-)-kainic acid and (+)-allo-kainic acid, which are pyrrolidine alkaloids used in neuroscience and neuropharmacology as useful molecular probes, was successfully achieved by using the stereo-complementary ring closure reactions promoted by SmI for the construction of the 2,3,4-trisubsituted pyrrolidine scaffold of kainoids.
[Mh] Termos MeSH primário: Compostos Alílicos/química
Iodetos/química
Ácido Caínico/análogos & derivados
Ácido Caínico/síntese química
Samário/química
[Mh] Termos MeSH secundário: Compostos Alílicos/síntese química
Ciclização
Ésteres/síntese química
Ésteres/química
Iodetos/síntese química
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Allyl Compounds); 0 (Esters); 0 (Iodides); 0 (samarium diiodide); 42OD65L39F (Samarium); SIV03811UC (Kainic Acid); V2RFT0R50S (allyl chloride)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1039/c7ob01427a


  7 / 17272 MEDLINE  
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[PMID]:29374707
[Au] Autor:Uesawa Y; Sakagami H; Okudaira N; Toda K; Takao K; Kagaya H; Sugita Y
[Ad] Endereço:Department of Clinical Pharmaceutics, Meiji Pharmaceutical University, Tokyo, Japan uesawa@my-pharm.ac.jp.
[Ti] Título:Quantitative Structure-Cytotoxicity Relationship of Cinnamic Acid Phenetyl Esters.
[So] Source:Anticancer Res;38(2):817-823, 2018 02.
[Is] ISSN:1791-7530
[Cp] País de publicação:Greece
[La] Idioma:eng
[Ab] Resumo:BACKGROUND/AIM: Many phenolic acid phenethyl esters possess diverse biological effects including antioxidant, cytoprotective, anti-inflammation and anti-tumor activities. However, most previous antitumor studies have not considered the cytotoxicity against normal cells. Ten cinnamic acid phenetyl esters were subjected to quantitative structure-activity relationship (QSAR) analysis, based on their cytotoxicity and tumor-specificity, in order to find their new biological activities. MATERIALS AND METHODS: Cytotoxicity against four human oral squamous cell carcinoma cell lines and three oral normal mesenchymal cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Tumor specificity (TS) was evaluated by the ratio of the mean 50% cytotoxic concentration (CC ) against normal oral cells to that against human oral squamous cell carcinoma cell lines. Potency-selectivity expression (PSE) value was calculated by dividing the TS value by CC against tumor cells. Apoptosis markers were detected by western blot analysis. Physicochemical, structural and quantum-chemical parameters were calculated based on the conformations optimized by force-field minimization. RESULTS: Western blot analysis demonstrated that [ ] stimulated the cleavage of caspase-3, suggesting the induction of apoptosis. QSAR analysis demonstrated that TS values were correlated with shape, size and ionization potential. CONCLUSION: Chemical modification of the lead compound may be a potential choice for designing a new type of anticancer drugs.
[Mh] Termos MeSH primário: Cinamatos/farmacologia
Ésteres/farmacologia
Álcool Feniletílico/farmacologia
[Mh] Termos MeSH secundário: Carcinoma de Células Escamosas/tratamento farmacológico
Carcinoma de Células Escamosas/patologia
Linhagem Celular Tumoral
Criança
Cinamatos/química
Cinamatos/toxicidade
Ésteres/química
Ésteres/toxicidade
Fibroblastos/efeitos dos fármacos
Neoplasias de Cabeça e Pescoço/tratamento farmacológico
Neoplasias de Cabeça e Pescoço/patologia
Seres Humanos
Masculino
Neoplasias Bucais/tratamento farmacológico
Neoplasias Bucais/patologia
Álcool Feniletílico/química
Álcool Feniletílico/toxicidade
Relação Quantitativa Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cinnamates); 0 (Esters); ML9LGA7468 (Phenylethyl Alcohol); U14A832J8D (cinnamic acid)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180129
[St] Status:MEDLINE


  8 / 17272 MEDLINE  
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[PMID]:29306024
[Au] Autor:Hill KL; Hamers T; Kamstra JH; Willmore WG; Letcher RJ
[Ad] Endereço:Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, National Wildlife Research Centre, Carleton University, Ottawa, Canada; Department of Biology, Carleton University, Ottawa, Canada; Intrinsik Corp., Ottawa, Canada.
[Ti] Título:Organophosphate triesters and selected metabolites enhance binding of thyroxine to human transthyretin in vitro.
[So] Source:Toxicol Lett;285:87-93, 2018 Mar 15.
[Is] ISSN:1879-3169
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The toxicological properties of organophosphate (OP) triesters that are used as flame retardants and plasticizers are currently not well understood, though increasing evidence suggests they can affect the thyroid system. Perturbation of thyroid hormone (TH) transport is one mechanism of action that may affect thyroid function. The present study applied an in vitro competitive protein binding assay with thyroxine (T4) and human transthyretin (hTTR) transport protein to determine the potential for the OP triesters, TDCIPP (tris(1,3-dichloro-2-propyl) phosphate), TBOEP (tris(butoxyethyl) phosphate), TEP (triethyl phosphate), TPHP (triphenyl phosphate), p-OH-TPHP (para-hydroxy triphenyl phosphate), and the OP diester DPHP (diphenyl phosphate), to competitively displace T4 from hTTR. Enhancement of T4 binding to hTTR, rather than the hypothesized competition, was observed for the six OP esters and in a concentration-dependent manner. For example, T4-hTTR binding was significantly increased at concentrations of TBOEP as low as 64 nM, and up to 184% of controls at 5000 nM. A plausible explanation of these results, which to our knowledge has not been previously reported, may be allosteric interactions of the OP esters with hTTR allowing T4 to access the second site of the TH binding pocket. These in vitro results suggest a novel mechanism of OP ester toxicity via T4 binding enhancement, and possible dysregulation of T4-hTTR interactions.
[Mh] Termos MeSH primário: Retardadores de Chama/toxicidade
Organofosfatos/toxicidade
Plastificantes/toxicidade
Pré-Albumina/metabolismo
Tiroxina/metabolismo
[Mh] Termos MeSH secundário: Ligação Competitiva
Ésteres
Retardadores de Chama/metabolismo
Seres Humanos
Organofosfatos/metabolismo
Plastificantes/metabolismo
Ligação Proteica
Glândula Tireoide/efeitos dos fármacos
Glândula Tireoide/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Esters); 0 (Flame Retardants); 0 (Organophosphates); 0 (Plasticizers); 0 (Prealbumin); Q51BO43MG4 (Thyroxine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180219
[Lr] Data última revisão:
180219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180107
[St] Status:MEDLINE


  9 / 17272 MEDLINE  
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[PMID]:29293588
[Au] Autor:Lyman M; Rubinfeld B; Leif R; Mulcahy H; Dugan L; Souza B
[Ad] Endereço:Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, California, United States of America.
[Ti] Título:Rhodotorula taiwanensis MD1149 produces hypoacetylated PEFA compounds with increased surface activity compared to Rhodotorula babjevae MD1169.
[So] Source:PLoS One;13(1):e0190373, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Biosurfactants have several desirable characteristics in the industrial sector: detergency, antimicrobial effects, skin hydration, and emulsibility. Several yeast glycolipids are currently being utilized in these capacities: sophorolipids, ustilagic acid, and mannosylerythritol lipids (MELs). An emerging class of glycolipids, termed polyol esters of fatty acids (PEFA), have recently been reported for Rhodotorula babjevae, a basidiomycetous yeast species that secretes hyperacetylated congeners of PEFA (typically with 3-6 acetylation modifications). While screening Rhodotorula species for surfactant production, we identified a new environmental isolate identified as Rhodotorula taiwanensis MD1149 that dropped the surface tension of the liquid medium, indicating that it produced a potent biosurfactant. Acid depolymerization of the purified biosurfactants, followed by gas chromatography-mass spectrometry (GC-MS) analysis revealed that the biosurfactants were composed of PEFA compounds composed mainly of mannitol and arabitol esters of 3-hydroxy fatty acid, 3-methoxy fatty acid, and fatty acids with a single double bond; chain lengths were mainly C16 and C18. Liquid chromatography-mass spectrometry (LC-MS) confirmed the predicted accurate mass of these compounds. Interestingly, PEFA compounds produced by Rhodotorula taiwanensis MD1149 were more surface active due to their hypoacetylation profile (0-4 acetylation modifications) compared to Rhodotorula babjevae MD1169. These disparate surface active properties, based on acetylation, change the hydrophilic-lipophilic balance (HLB) of these compounds, and their potential utility within industrial applications.
[Mh] Termos MeSH primário: Ácidos Graxos/biossíntese
Polímeros/metabolismo
Rhodotorula/metabolismo
[Mh] Termos MeSH secundário: Acetilação
Cromatografia Líquida de Alta Pressão
Ésteres
Ácidos Graxos/metabolismo
Cromatografia Gasosa-Espectrometria de Massas
Interações Hidrofóbicas e Hidrofílicas
Peso Molecular
Rhodotorula/classificação
Extração em Fase Sólida
Especificidade da Espécie
Espectrometria de Massas por Ionização por Electrospray
Tensão Superficial
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Esters); 0 (Fatty Acids); 0 (Polymers); 0 (polyol)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180103
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190373


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[PMID]:29311504
[Au] Autor:Konishi H
[Ad] Endereço:School of Pharmaceutical Sciences, University of Shizuoka.
[Ti] Título:Creation of Novel Toxic Gas Surrogates and the Development of Safe and Facile Catalytic Reactions.
[So] Source:Chem Pharm Bull (Tokyo);66(1):1-19, 2018.
[Is] ISSN:1347-5223
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:The use of toxic gas surrogates in organic reactions instead of the gas itself contributes to enhancing the safety, practicality, and efficiency of the reactions involved. Our efforts toward the creation of toxic gas surrogates and the development of a series of catalytic reactions using these surrogates are described. Improvements in substrate scope during the hydroesterification of alkenes using formates facilitated by the Ru-imidazole catalyst system provided the opportunity to discover that phenyl formate is a useful carbon monoxide (CO) surrogate for the generation of CO and phenol under weakly basic conditions. This discovery triggered the development of highly reactive but stable CO surrogates and a variety of Pd-catalyzed carbonylative transformations. N-Formylsaccharin facilitated the use of additional nucleophiles in carbonylation reactions that provided access to a variety of carbonyl compounds. Detailed experimental and theoretical mechanistic studies into the generation of CO from phenyl formate suggest that CO generation proceeds via a concerted E2 α-elimination. Furthermore, a known surrogate of sulfur dioxide was applied for the first time to the selective syntheses of cyclic sulfonamides and sulfinamides, confirming that the surrogate operates as an "S=O" source. Notably, the reactions described herein are scalable and can be performed without the use of external toxic gases and specialized reaction vessels; they are easy and simple to perform and demonstrate enormous potential for industrial application.
[Mh] Termos MeSH primário: Alcenos/química
Monóxido de Carbono/química
Ésteres/síntese química
Paládio/química
[Mh] Termos MeSH secundário: Catálise
Ésteres/química
Estrutura Molecular
Fenóis/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Alkenes); 0 (Esters); 0 (Phenols); 5TWQ1V240M (Palladium); 7U1EE4V452 (Carbon Monoxide)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1248/cpb.c17-00795



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