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1.
Tumour Biol ; 42(7): 1010428320938494, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32628088

RESUMO

Radiotherapy and cisplatin lead to cell killing in head and neck squamous cell carcinoma patients, but adverse events and response to treatment are not the same in patients with similar clinicopathological aspects. The aim of this prospective study was to evaluate the roles of TP53 c.215G > C, FAS c.-671A > G, FAS c.-1378G > A, FASL c.-844 C > T, CASP3 c.-1191A > G, and CASP3 c.-182-247G > T single nucleotide variants in toxicity, response rate, and survival of cisplatin chemoradiation-treated head and neck squamous cell carcinoma patients. Genomic DNA was analyzed by polymerase chain reaction for genotyping. Differences between groups of patients were analyzed by chi-square test or Fisher's exact test, multiple logistic regression analysis, and Cox hazards model. One hundred nine patients with head and neck squamous cell carcinoma were enrolled in study. All patients were smokers and/or alcoholics. Patients with FAS c.-671GG genotype, FAS c.-671AG or GG genotype, and FASL c.-844CC genotype had 5.52 (95% confidence interval (CI): 1.42-21.43), 4.03 (95% CI: 1.51-10.79), and 5.77 (95% CI: 1.23-27.04) more chances of presenting chemoradiation-related anemia of grades 2-4, lymphopenia of grade 3 or 4, and ototoxicity of all grades, respectively, than those with the remaining genotypes. FAS c.-671GG genotype was also seen as an independent predictor of shorter event-free survival (hazard ratio (HR): 2.05; P = 0.007) and overall survival (HR: 1.83; P = 0.02) in our head and neck squamous cell carcinoma patients. These findings present, for the first time, preliminary evidence that inherited abnormalities in apoptosis pathway, related to FAS c.-671A > G and FASL c.-844 C > T single nucleotide variants, can alter toxicity and survival of tobacco- and alcohol-related head and neck squamous cell carcinoma patients homogeneously treated with cisplatin chemoradiation.


Assuntos
Proteína Ligante Fas/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Receptor fas/genética , Adulto , Idoso , Álcoois/efeitos adversos , Quimiorradioterapia/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/induzido quimicamente , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Tabaco/efeitos adversos , Proteína Supressora de Tumor p53/genética
2.
Food Chem ; 330: 127330, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569941

RESUMO

Conventional analysis, electronic senses and HS-SPME-GC-MS were applied to evaluate the effects of pretreatment methods and leaching methods on jujube wine quality. Significant differences (p < 0.05) in the levels of alcohol content, color, taste and aroma were observed among all the jujube wine samples, in which the pulp and pectase fermented jujube wine was the best among all. Moreover, rather than taste, aroma is the most significantly (p < 0.05) affected. In regard to aroma, a total of 182 volatile compounds were identified by HS-SPME-GC-MS. It was found that the blended-into-pulp treatment and the leached-by-pectase treatment had notable positive effects on jujube wine. The pulp and pectase fermented jujube wines exhibited the highest concentration of total volatile compounds as well as alcohols, esters, acids and aldehydes. Thus, the optimal pretreatment method and leaching method for jujube wine fermentation are blended-into-pulp and leached-by-pectase respectively.


Assuntos
Análise de Alimentos/métodos , Qualidade dos Alimentos , Vinho/análise , Ziziphus , Álcoois/análise , Aldeídos/análise , Cor , Nariz Eletrônico , Ésteres/análise , Fermentação , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Análise Multivariada , Odorantes/análise , Microextração em Fase Sólida/métodos , Paladar , Compostos Orgânicos Voláteis/análise , Ziziphus/química
3.
Nature ; 584(7819): 69-74, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32512577

RESUMO

Enzymes are increasingly explored for use in asymmetric synthesis1-3, but their applications are generally limited by the reactions available to naturally occurring enzymes. Recently, interest in photocatalysis4 has spurred the discovery of novel reactivity from known enzymes5. However, so far photoinduced enzymatic catalysis6 has not been used for the cross-coupling of two molecules. For example, the intermolecular coupling of alkenes with α-halo carbonyl compounds through a visible-light-induced radical hydroalkylation, which could provide access to important γ-chiral carbonyl compounds, has not yet been achieved by enzymes. The major challenges are the inherent poor photoreactivity of enzymes and the difficulty in achieving stereochemical control of the remote prochiral radical intermediate7. Here we report a visible-light-induced intermolecular radical hydroalkylation of terminal alkenes that does not occur naturally, catalysed by an 'ene' reductase using readily available α-halo carbonyl compounds as reactants. This method provides an efficient approach to the synthesis of various carbonyl compounds bearing a γ-stereocentre with excellent yields and enantioselectivities (up to 99 per cent yield with 99 per cent enantiomeric excess), which otherwise are difficult to access using chemocatalysis. Mechanistic studies suggest that the formation of the complex of the substrates (α-halo carbonyl compounds) and the 'ene' reductase triggers the enantioselective photoinduced radical reaction. Our work further expands the reactivity repertoire of biocatalytic, synthetically useful asymmetric transformations by the merger of photocatalysis and enzyme catalysis.


Assuntos
Alcenos/química , Alcenos/metabolismo , Hidrogênio/química , Hidrogênio/metabolismo , Luz , Oxirredutases/metabolismo , Processos Fotoquímicos/efeitos da radiação , Álcoois/química , Álcoois/metabolismo , Alquilação/efeitos da radiação , Biocatálise/efeitos da radiação , Biomassa , Carboxiliases/metabolismo , Flavinas/metabolismo , Modelos Químicos , Modelos Moleculares , Estereoisomerismo
4.
Nat Commun ; 11(1): 2756, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488003

RESUMO

Trifluoroethanol and difluoroethanol units are important motifs in bioactive molecules, but the methods to direct incorporate these units are limited. Herein, we report two organosilicon reagents for the transfer of trifluoroethanol and difluoroethanol units into molecules. Through intramolecular C-Si bond activation by alkoxyl radicals, these reagents were applied in allylation, alkylation and alkenylation reactions, enabling efficient synthesis of various tri(di)fluoromethyl group substituted alcohols. The broad applicability and general utility of the approach are highlighted by late-stage introduction of these fluoroalkyl groups to complex molecules, and the synthesis of antitumor agent Z and its difluoromethyl analog Z'.


Assuntos
Etanol/análogos & derivados , Etanol/química , Compostos de Organossilício/química , Trifluoretanol/química , Álcoois/química , Alquilação , Técnicas de Química Sintética , Indicadores e Reagentes/química , Estrutura Molecular
5.
Nat Commun ; 11(1): 3080, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32555154

RESUMO

The exact chemical structure of non-crystallising natural products is still one of the main challenges in Natural Sciences. Despite tremendous advances in total synthesis, the absolute structural determination of a myriad of natural products with very sensitive chemical functionalities remains undone. Here, we show that a metal-organic framework (MOF) with alcohol-containing arms and adsorbed water, enables selective hydrolysis of glycosyl bonds, supramolecular order with the so-formed chiral fragments and absolute determination of the organic structure by single-crystal X-ray crystallography in a single operation. This combined strategy based on a biomimetic, cheap, robust and multigram available solid catalyst opens the door to determine the absolute configuration of ketal compounds regardless degradation sensitiveness, and also to design extremely-mild metal-free solid-catalysed processes without formal acid protons.


Assuntos
Produtos Biológicos/química , Hidrolases/química , Estruturas Metalorgânicas/química , Adsorção , Álcoois/química , Catálise , Cristalografia por Raios X , Glicólise , Hidrólise , Cinética , Metais , Conformação Molecular , Estrutura Molecular , Porosidade , Relação Estrutura-Atividade , Difração de Raios X
6.
Food Chem ; 328: 126967, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32505057

RESUMO

Different particle sizes in cloudy apple juice were obtained following filtration with different mesh sizes (100, 200, 300, and 400-mesh). The effects of cloud particle size on the stability, nutrient content, and volatile flavor of cloudy apple juice were evaluated. With increasing mesh number, particle size decreased (p < 0.05) and particle shape changed. Particle size had an effect on volatile flavor compounds, especially nitrogen oxides, alcohols, and aromatic compounds. The content of pectin and total phenol decreased with decreasing particle size, while the content of soluble protein was not affected. The reduction of cloud particle size increased absolute value of ζ-potential, cloud stability, and apparent viscosity and decreased turbidity and cloud values. Pearson correlation analysis showed that there was a strong correlation between particle size and quality indicators, except for soluble protein.


Assuntos
Aromatizantes/química , Sucos de Frutas e Vegetais/análise , Malus/química , Álcoois/análise , Malus/metabolismo , Microscopia de Força Atômica , Óxidos de Nitrogênio/análise , Tamanho da Partícula , Fenóis/análise , Viscosidade
7.
Nat Commun ; 11(1): 2890, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513962

RESUMO

Employment of sulfoxides as electrophiles in cross-coupling reactions remains underexplored. Herein we report a transition-metal-free cross-coupling strategy utilizing aryl(heteroaryl) methyl sulfoxides and alcohols to afford alkyl aryl(heteroaryl) ethers. Two drug molecules were successfully prepared using this protocol as a key step, emphasizing its potential utility in medicinal chemistry. A DFT computational study suggests that the reaction proceeds via initial addition of the alkoxide to the sulfoxide. This adduct facilitates further intramolecular addition of the alkoxide to the aromatic ring wherein charge on the aromatic system is stabilized by the nearby potassium cation. Rate-determining fragmentation then delivers methyl sulfenate and the aryl or heteroaryl ether. This study establishes the feasibility of nucleophilic addition to an appended sulfoxide as a means to form a bond to aryl(heteroaryl) systems and this modality is expected to find use with many other electrophiles and nucleophiles leading to new cross-coupling processes.


Assuntos
Álcoois/química , Éteres/química , Hidrocarbonetos Policíclicos Aromáticos/química , Sulfóxidos/química , Elementos de Transição/química , Carbono/química , Catálise , Química Farmacêutica/métodos , Compostos Heterocíclicos/química , Hidrocarbonetos Aromáticos/química , Metais/química , Modelos Químicos , Estrutura Molecular , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Enxofre/química
8.
Int J Pharm ; 584: 119431, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: covidwho-277012

RESUMO

The world is facing a medical crisis amid the CoViD-19 pandemic and the role of adequate hygiene and hand sanitisers is inevitable in controlling the spread of infection in public places and healthcare institutions. There has been a great surge in demand for hand sanitisation products leading to shortages in their supply. A consequent increase of substandard products in the market has raised safety concerns. This article, therefore, presents a critical review of hand sanitation approaches and products available on the market in light of the scientific evidence available to date. This review also provides a range of hand sanitisation product formulations, and manufacturing instructions to allow for extemporaneous preparations at the community and hospital pharmacies during this urgent crisis. In addition, this emergent situation is expected to continue, hence hand sanitisers will be in demand for an extended time, and the availability and purchase of substandard products on the market create an ongoing safety concern. Therefore, this article shall also provide various commercial organisations, interested in stepping forward the production and marketing of hand sanitisers, with a guide on the development of products of standardised ingredients and formulations.


Assuntos
Álcoois/química , Infecções por Coronavirus/prevenção & controle , Desinfetantes/química , Composição de Medicamentos , Desinfecção das Mãos/métodos , Higiene das Mãos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Desinfetantes/uso terapêutico , Humanos
9.
Food Chem ; 324: 126903, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32361095

RESUMO

Cuticular wax chemicals differ among fruit cultivars and contribute to storage ability. However, wax analysis in apple cultivars, particularly during storage, has not been described. In this work, the chemicals and crystal structures of cuticular wax in 10 apple cultivars were analyzed to observe wax functions in apple during storage. Results showed that alkanes and primary alcohols decreased while fatty acids increased in stored fruits of all cultivars compared with the fruits before storage. Terpenoids, aldehydes, and phenols were observed in stored fruits but not in the fruits before storage in all cultivars except 'Red Star' fruit. The weight loss rate was significantly correlated with six components including C13 alcohol, C14 alkanes, total alkanes, total wax, C13 alkanes and C54 alkanes in 10 cultivar apple fruits during storage. Our findings indicate that the total wax, particularly alkanes, in the peel of apple fruits is essential for storage and quality control.


Assuntos
Armazenamento de Alimentos/métodos , Malus/química , Ceras/química , Álcoois/metabolismo , Aldeídos/análise , Alcanos/metabolismo , Ácidos Graxos/metabolismo , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Malus/metabolismo , Fenóis/análise , Terpenos/análise , Ceras/análise
10.
Adv Exp Med Biol ; 1195: 189-198, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468477

RESUMO

In the present work, new indole derivatives, i.e., 5-[N,N-di alkyl amino alkoxy] azaindole 2,3- di-one derivatives, are synthesized and characterized. These compounds were subjected to acute toxicity and then screened for antiepileptic activity on maximal electroshock seizure (MES) model in albino Wistar rats. In that study 5-[2-dimethyl amino ethoxy] Azaindole-3-hydrazone,2-one and 5-[2- dimethyl amino ethoxy] Azaindole 2-one,3-thiothiosemicarbazone(IIIa) showed good antiepileptic activity and less neurotoxicity compared to phenytoin. The purpose of the present study is to investigate the effect of 5-[2-dimethyl amino ethoxy] Indole 2,3- di one and 5-[2-dimethyl amino ethoxy] Azaindole 2-one,3-thiosemicarbazone(IIIa) derivatives on biogenic amines concentrations in rat brain after induction of seizures by MES method. The aim of study was relationship between seizure activities and altered the monoamines such as Noradrenaline (NA), Dopamine (DA), Serotonin (5-HT) in forebrain of rats in MES seizure models. In MES model, study of 5-[2-dimethyl amino ethoxy] Azaindole 3-hydrazone,2-one(Va) and 5-[2-dimethyl amino ethoxy]Azaindole 2-one,3-thiosemicarbazone(IIIa) (100 mg/kg) showed significant restoration of the decreased levels of brain monoamines such as noradrenaline, dopamine, and 5-hydroxytryptamine. Thus, this study suggests that 5-[2-Dimethyl amino ethoxy] Azaindole 3-hydrazone,2-one (V) and 5-[2-dimethyl amino ethoxy] Azaindole 2-one,3-thiosemicarbazone (IIIa) increased the monoamines on rat brain, which may decrease the susceptibility to MES-induced seizure in rats.


Assuntos
Anticonvulsivantes/síntese química , Anticonvulsivantes/uso terapêutico , Indóis/síntese química , Indóis/uso terapêutico , Tiossemicarbazonas/síntese química , Tiossemicarbazonas/uso terapêutico , Álcoois/síntese química , Álcoois/química , Álcoois/farmacologia , Álcoois/uso terapêutico , Animais , Anticonvulsivantes/química , Anticonvulsivantes/farmacologia , Modelos Animais de Doenças , Hidrazonas/síntese química , Hidrazonas/química , Hidrazonas/farmacologia , Hidrazonas/uso terapêutico , Indóis/química , Indóis/farmacologia , Ratos , Ratos Wistar , Convulsões/tratamento farmacológico , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia
11.
Sci Total Environ ; 730: 138324, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32388385

RESUMO

Plants are excellent climate indicators and their macro-remains or pollen accumulating in geological archives serve as recorders of environmental change. In Europe birch trees contribute importantly to Holocene plant successions. They constitute the dwarf species Betula nana and B. humilis, representing colder and two tree birches, B. pubescens and B. pendula indicative of more temperate climate. Birch pollen is highly similar preventing species differentiation. We obtained unambiguous chemotaxonomic differentiation of four European birch species via cuticular wax lipids. Dominating lipid classes in recent epicuticular birch waxes were n-alkanes (nC23 to nC33), n-alcohols and n-alkanoic acids (nC20 to nC32), and long-chain wax ester (nC36 to nC48) differing in amount and distribution. After plant senescence and in geological archives lipids undergo diagenetic alteration modifying the distributions found in recent plants. Long-chain wax esters via hydrolysis release bound n-alcohols and n-fatty acids, adding to their free analogues. Simulated release of bound lipids increased the pool of n-alcohol and n-fatty acids up to 400%. Such modification of primary lipid patterns is unaccounted for in most paleovegetation studies. Proceeding diagenesis, e.g. by decarboxylation will convert these functionalized primary and secondary lipids into their corresponding n-alkanes, the compound class mostly applied in paleoenvironment reconstruction. The simulated n-alkane pattern changed significantly, evidenced by an increase of mid-chain (nC23,nC25) homologues. Release of bound lipids may not only alter molecular but also isotopic composition, which may cause errors in paleoclimate reconstruction. We assessed the potential contribution of secondary (free lipid decarboxylation) and tertiary (bound lipid decarboxylation) wax metabolites and compared the cumulative n-alkane patterns with birch n-alkane distributions reported in the literature. Two statistically different patterns were separated, one dominated by primary, the other by secondary and tertiary formed n-alkanes. This may explain the inconsistency in previous birch wax analysis reported and needs consideration in paleoenvironment reconstruction.


Assuntos
Betula , Álcoois , Europa (Continente) , Ácidos Graxos , Folhas de Planta , Ceras
12.
Int J Pharm ; 584: 119431, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32461194

RESUMO

The world is facing a medical crisis amid the CoViD-19 pandemic and the role of adequate hygiene and hand sanitisers is inevitable in controlling the spread of infection in public places and healthcare institutions. There has been a great surge in demand for hand sanitisation products leading to shortages in their supply. A consequent increase of substandard products in the market has raised safety concerns. This article, therefore, presents a critical review of hand sanitation approaches and products available on the market in light of the scientific evidence available to date. This review also provides a range of hand sanitisation product formulations, and manufacturing instructions to allow for extemporaneous preparations at the community and hospital pharmacies during this urgent crisis. In addition, this emergent situation is expected to continue, hence hand sanitisers will be in demand for an extended time, and the availability and purchase of substandard products on the market create an ongoing safety concern. Therefore, this article shall also provide various commercial organisations, interested in stepping forward the production and marketing of hand sanitisers, with a guide on the development of products of standardised ingredients and formulations.


Assuntos
Álcoois/química , Infecções por Coronavirus/prevenção & controle , Desinfetantes/química , Composição de Medicamentos , Desinfecção das Mãos/métodos , Higiene das Mãos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Desinfetantes/uso terapêutico , Humanos
13.
Food Chem ; 326: 126856, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32450481

RESUMO

Volatile fingerprints of a lager beer were carried out throughout five brewing steps to characterize the changes encompassing this process. Overall, 60 volatile organic metabolites (VOMs) were identified by headspace solid-phase microextraction followed by gas chromatography mass spectrometry (HS-SPME/GC-MS). Specific profiles were observed at different brewing steps - aldehydes and furans dominate in wort, whereas the aliphatic esters and alcohols predominate in the following steps. Such variations can be assigned to specific VOMs, as 3-methylbutanal (wort), ethyl alcohol and ethyl octanoate (fermentation, maturation and filtration), or ethyl alcohol and isoamyl acetate (final product). These VOMs can influence the beer final flavour. Ethyl alcohol contributes to its strong and pungent smell and taste, while isoamyl acetate adds intense 'fruity' and 'banana' odours. These beer volatile fingerprints constitute a valuable tool to obtain insights on the impact of each brewing step on the final product, being also very useful for certification purposes.


Assuntos
Cerveja/análise , Álcoois/análise , Aldeídos/análise , Ésteres/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Pentanóis/análise , Microextração em Fase Sólida , Paladar , Compostos Orgânicos Voláteis/análise , Volatilização
14.
Food Chem ; 321: 126691, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32251922

RESUMO

Low-alcohol Huangjiu (LAH), which contains reduced contents of ethanol and higher alcohols, is prepared by diluting original Huangjiu that has a high ethanol content, which leads to a weakened flavor (i.e., acidity). To increase acidity and reduce higher alcohols level in LAH, the gene ALD6 encoding aldehyde dehydrogenase was expressed in yeast HJ-1 under the control of the pPGK1 promoter and terminators with varying activities (tGIC1, tPGK1 and tCPS1) by scarless replacement at BAT2 locus, yielding the engineered strains HJΔB-AG, HJΔB-AP, and HJΔB-AC. The acetate concentration produced by HJΔB-AG, HJΔB-AP, and HJΔB-AC was 1.26-, 1.84-, and 2.51-fold of that of HJ-1, respectively. Furthermore, the concentration of higher alcohols produced by HJΔB-AG, HJΔB-AP, and HJΔB-AC decreased by 39.91%, 45.55%, and 52.80%, respectively. This study resulted in the creation of promising recombinant yeast strains and introduced a method that can be used for the high-quality production of LAH by acid-producing Saccharomyces cerevisiae.


Assuntos
Etanol/metabolismo , Microrganismos Geneticamente Modificados , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Acetatos/metabolismo , Álcoois , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Fermentação , Microbiologia de Alimentos , Regiões Promotoras Genéticas , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Regiões Terminadoras Genéticas , Transaminases/genética , Transaminases/metabolismo
15.
Zhongguo Zhong Yao Za Zhi ; 45(2): 233-241, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237304

RESUMO

Lonicerae Japonicae Flos and Artemisiae Annuae Herba(LA or Jinqing) alcohol precipitation has various process parameters and complex process mechanism, and is one of the key units for manufacturing Reduning Injection. In order to identify the critical process parameters(CPPs) affecting the weight of the extract produced from the alcohol precipitation process, 259 batches of historical production data from 2017 to 2018 were collected, with a total of 829 318 data points. These data showed characteristics of large data, such as a large data volume, a low value density, and diverse sources. The data cleaning and feature extraction were first performed, and 48 feature variables were selected. The original data points were reduced to 9 936. Then, a combination of Pearson correlation analysis and grey correlation analysis were used to screen out 15 potential critical process parameters(pCPPs). After that, the partial least squares(PLS) was used in prediction of the weight of the extract, proving that the performance of predictive model based on 15 pCMAs is equivalent to that of predictive model based on 48 feature variables. The variable importance in projection(VIP) index was used to identify 9 CPPs, including 2 alcohol precipitation supernatant volume parameters, 4 initial extract weight parameters and 3 added alcohol volume parameters. As a result, the number of data points was 1 863, accounting for 0.28% of the original data. The big data analysis approach from a holistic point of view can effectively increase the value density of the original data. The critical process parameters obtained can help to accurately describe the quality transfer mechanism of the Jinqing alcohol precipitation process.


Assuntos
Big Data , Medicamentos de Ervas Chinesas/química , Álcoois , Solventes , Tecnologia Farmacêutica
16.
Food Chem ; 320: 126610, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32234655

RESUMO

This paper presents a study of the influence of the harvesting date on concentrations of odorants in Moristel wines of two vintages. The wine made from grapes harvested early facilitated the accumulation of acetaldehyde (associated with low polyphenols concentrations) and higher concentrations of branched acids. A reason for these greater levels could be the lack of reduction factors (NADH or NADPH). Other changes with potential sensory consequences are the decrease of the branched acid/branched alcohol, branched ester/branched acid and branched ester/branched alcohol ratios that occurs as the grapes ripen. Besides, the variations of varietal or typical maturation markers did not have sensory importance. These results suggest that the characteristics of wines associated to the degree of maturity of grapes are mostly related to the changes in the profiles of fermentative compounds (especially acetaldehyde) induced by changes in the polyphenolic content and in the medium in which the yeast develops.


Assuntos
Fermentação , Manipulação de Alimentos , Compostos Orgânicos Voláteis/análise , Vinho/análise , Acetaldeído/análise , Acetaldeído/metabolismo , Álcoois/análise , Álcoois/metabolismo , Ésteres/análise , Ésteres/metabolismo , Odorantes/análise , Saccharomyces cerevisiae/metabolismo , Estações do Ano , Vitis/química , Compostos Orgânicos Voláteis/metabolismo
17.
Emerg Infect Dis ; 26(7): 1592-1595, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32284092

RESUMO

Infection control instructions call for use of alcohol-based hand rub solutions to inactivate severe acute respiratory syndrome coronavirus 2. We determined the virucidal activity of World Health Organization-recommended hand rub formulations, at full strength and multiple dilutions, and of the active ingredients. All disinfectants demonstrated efficient virus inactivation.


Assuntos
Álcoois/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/prevenção & controle , Desinfetantes/farmacologia , Desinfecção das Mãos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Inativação de Vírus , Humanos , Organização Mundial da Saúde
18.
J Chromatogr A ; 1620: 460987, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32115231

RESUMO

It is critical to determine the chiral impurity profile of pharmaceutical compounds. The rising trend of drug candidates bearing multiple chiral centers has aggravated the analytical challenges. The traditional chiral HPLC methods can take gruelingly long time to develop yet may not offer sufficient resolution for all stereoisomers. A fast analytical strategy with a high success rate is in urgent demand for compounds with multiple chiral centers. In this study, we have developed an effective and fast multiple heart-cutting (MHC) multicolumn two-dimensional liquid chromatography (LC-mLC) platform approach. The m in the name of LC-mLC highlights the employment of multiple chiral columns with different chiral selectors and mobile phases in the second dimension (2D) within the same run. A short achiral HPLC method in the first dimension (1D) allows the separation of diastereomers and other achiral impurities, followed by 2D analysis enabling different chiral columns and different mobile phases on each coeluted 1D peak for maximum resolution. This LC-mLC strategy breaks down the complex multiple-chiral-center separation problems into simple individual one-chiral-center separation, which dramatically reduces chiral method development time and sample analysis turnaround. Its versatile nature and fast turnaround approach have made it a highly efficient strategy to enable quick stereoselective synthetic route development. This platform LC-mLC strategy has been successfully demonstrated in separating eight stereoisomers for a pharmaceutical compound with 3 chiral centers, within total method development time of less than 2 hours and a final analysis time of less than 24 min, including column equilibration time. It was also proved highly efficient in separating multiple chiral and achiral components in an in-process sample containing structurally similar starting materials, intermediates, side products and multiple stereoisomers of the product with 3 chiral centers, with minimal method development time.


Assuntos
Cromatografia Líquida/métodos , Álcoois/química , Reprodutibilidade dos Testes , Estereoisomerismo
19.
Chem Pharm Bull (Tokyo) ; 68(3): 258-264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115533

RESUMO

Oxo-octadecadienoic acids (OxoODEs) act as peroxisome proliferator-activated receptor (PPAR) agonists biologically, and are known to be produced in the lipoxygenase/linoleate system. OxoODEs seem to originate from the linoleate alkoxyl radicals that are generated from (E/Z)-hydroperoxy octadecadienoic acids ((E/Z)-HpODEs) by a pseudoperoxidase reaction that is catalyzed by ferrous lipoxygenase. However, the mechanism underlying the conversion of alkoxyl radical into OxoODE remains obscure. In the present study, we confirmed that OxoODEs are produced in the lipoxygenase/linoleate system in an oxygen-dependent manner. Interestingly, we revealed a correlation between the (E/Z)-OxoODEs content and the (E/E)-HpODEs content in the system. (E/E)-HpODEs could have been derived from (E/E)-linoleate peroxyl radicals, which are generated by the reaction between a free linoleate allyl radical and an oxygen molecule. Notably, the ferrous lipoxygenase-linoleate allyl radical (LOx(Fe2+)-L·) complex, which is an intermediate in the lipoxygenase/linoleate system, tends to dissociate into LOx(Fe2+) and a linoleate allyl radical. Subsequently, LOx(Fe2+) converts (E/Z)-HpODEs to an (E/Z)-linoleate alkoxyl radical through one-electron reduction. Taken together, we propose that (E/Z)-OxoODEs and (E/E)-HpODEs are produced through radical-radical dismutation between (E/Z)-linoleate alkoxyl radical and (E/E)-linoleate peroxyl radical. Furthermore, the production of (E/Z)-OxoODEs and (E/E)-HpODEs was remarkably inhibited by a hydrophobic radical scavenger, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO). On the contrary, water-miscible radical scavengers, 4-hydroxyl-2,2,6,6-tetramethylpiperidine 1-oxyl (OH-TEMPO) and 3-carbamoyl-2,2,5,5-tetramethyl-3-pyrroline-N-oxyl (CmΔP) only modestly or sparingly inhibited the production of (E/Z)-OxoODEs and (E/E)-HpODEs. These facts indicate that the radical-radical dismutation between linoleate alkoxyl radical and linoleate peroxyl radical proceeds in the interior of micelles.


Assuntos
Álcoois/metabolismo , Ácidos Graxos/metabolismo , Lipoxigenases/metabolismo , Oxigênio/metabolismo , Peróxidos/metabolismo , Álcoois/química , Biocatálise , Ácidos Graxos/química , Estrutura Molecular , Oxigênio/química , Peróxidos/química
20.
Food Chem ; 317: 126379, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087515

RESUMO

Although significant amounts of polymers associated with adverse health effects in oils are produced during frying, the chemical bonds forming these polymers are not well understood. This study revealed that ester bonds are responsible for the polymerization of soybean oil during frying and heating at 175 °C. The ester value of soybean oil increased during frying up to day 3 of the experiment and slightly decreased on day 4 of the experiment indicating that esterification and hydrolysis concomitantly occurred. The 13C NMR spectra showed further evidence of the formation of ester bonds. This study also examined unidentified chemical bonds in the polymer products, other than ester bonds, with NMR spectroscopy. No NMR signals indicating ether bonds were observed. The NMR study after the reaction of oxidized soybean oil with acetyl chloride clarified assignments of proton signals, confirming some previous assignments, and assigning a new proton signal as an alcohol.


Assuntos
Álcoois/análise , Polímeros/análise , Óleo de Soja/química , Culinária , Ésteres/análise , Temperatura Alta/efeitos adversos , Oxirredução
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