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1.
Chemosphere ; 240: 124762, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568940

RESUMO

The emission of polychlorinated biphenyls (PCBs) in South Asian countries is one of the great environmental concerns and has resulted in the contamination of surrounding high altitude regions such as Azad Jammu and Kashmir (AJK), Pakistan. This first investigation of Polychlorinated Biphenyl (PCBs) concentrations in the ambient air, water and surface soil was conducted along the extensive stream network in the AJK valley of the Himalayan Region. In 2014, surface soil samples were taken and passive air and water samplers were deployed along the four main rivers, namely Jhelum, Neelum, Poonch and Kunhar, and analysed for PCBs (33 congeners) using GC-MS/MS. The ∑33PCBs concentrations ranged from 31.17 to 175.2 (mean ±â€¯SD: 81 ±â€¯46.4 pg/L), ND to 1908 (1054 ±â€¯588.5 pg/g), and 29.8 to 94.4 (52.9 ±â€¯22.7 pg/m3) in surface water, soil and air matrices, respectively. The levels of dioxin-like PCBs (∑8DL-PCBs) contributed considerably towards the total PCBs concentrations: 60.63% (water), 43.87% (air) and 13.76% (soil). The log transformed air-water fugacity (log fa/fw) ratios ranged from -9.37 to 2.58; with 86.3% of the sampling sites showing net volatilization of selected PCB congeners. Similarly, the fugacity fractions for air-soil exchange exhibited narrow variation (0.8 to < 1) indicating net volatilization of PCBs. The ecological risk assessment showed low potential ecological risks (Eri  = 1.58-7.63) associated with PCB contamination. The present findings provide baseline data that suggest cold trapping of POPs in the remote mountainous areas of Pakistan and can support environmental management of POPs at the regional level. This pioneer investigation campaign to assess the PCBs concentrations in Himalayan Riverine Network of Azad Jammu and Kashmir, Pakistan helps to develop baseline data of PCBs from the strategically important riverine environment that would help in future regional as well as global ecological studies. However, the effects of temperature variations on the sampling rates of chemicals across a wide spectrum of volatility along the elevation gradient were not taken under consideration for PCBs atmospheric concentrations.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Bifenilos Policlorados/análise , Paquistão , Rios , Solo , Poluentes do Solo/análise , Espectrometria de Massas em Tandem , Volatilização , Água/análise , Poluentes Químicos da Água/análise
2.
Sci Total Environ ; 700: 134469, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31693961

RESUMO

The presence of contaminants of emerging concern (CECs), such as antibiotics, antimicrobial disinfectants, nonprescription drugs, personal care products, pharmaceuticals, and steroids, in water resources can impact aquatic and human health. A large portion of the CECs entering regional wastewater treatment plants originate from hospitals. The purposes of this study were to conduct exploratory analytical work to characterize two hospital wastewaters and to evaluate treatment of CECs at hospitals before dilution with domestic wastewater. A 24-h batch reaction with biogenic manganese oxides coated onto coir fiber was used to treat the wastewaters. Organic contaminants in the wastewaters were concentrated by both liquid-liquid extraction (LLE) and solid-phase extraction (SPE). LLE extracts were analyzed by Comprehensive Two-Dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry (GC × GC-TOFMS) while SPE extracts were analyzedby UltraHigh Performance Liquid Chromatography/Time-of-Flight Mass Spectrometry (UHPLC-TOFMS). Fifty-two organic micropollutants were detected (26 by GC × GC-TOFMS, 25 by UHPLC-TOFMS, 1 by both) in the wastewaters, while 29 were removed by >90% and six were degraded by <50% after treatment. Control experiments revealed that sorption to coir fiber and oxidation by manganese oxides were the primary contaminant removal mechanisms. Both the LLE and SPE extracts were used to evaluate potential human toxicity of the hospital wastewaters before and after treatment. Twenty-eight human cell-based bioreceptor assays were used to screen the wastewaters, and secondary tests were run to quantify toxicity equivalents to activated receptors. The wastewaters initially contained organic micropollutants that strongly activated the Androgen Receptor, Estrogen Receptor ß, and the Mineralocorticoid Receptor but no bioactive compounds were detected after treatment. Point-of-entry treatment of hospital wastewater should reduce bioactive compounds from entering the environment.


Assuntos
Monitoramento Ambiental , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Hospitais , Extração Líquido-Líquido , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Águas Residuárias
3.
Biosci Biotechnol Biochem ; 84(1): 118-125, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31516066

RESUMO

We developed an enzymatic assay system enabling easy quantification of 4-aminobutyric acid (GABA). The reaction of GABA aminotransferase obtained from Streptomyces decoyicus NBRC 13977 was combined to those of the previously developed glutamate assay system using glutamate oxidase and peroxidase. The three-enzyme system allowing GABA-dependent dye formation due to the oxidative coupling between 4-aminoantipyrine and Trinder's reagent enabled accurate quantification of 0.2 - 150 mg/L GABA. A pretreatment mixture consisting of glutamate oxidase, ascorbate oxidase and catalase eliminating glutamate, ascorbate, and hydrogen peroxide, respectively, was also prepared to remove those inhibitory substances from samples. Thus, constructed assay kit was used to measure the GABA content in tomato samples. The results were almost the same as that obtained by the conventional method using liquid chromatography-tandem mass spectrometry. The kit will become a promising tool especially for the on-site measurement of GABA content in agricultural products.


Assuntos
4-Aminobutirato Transaminase/química , Aminoácido Oxirredutases/química , Colorimetria/métodos , Ensaios Enzimáticos/métodos , Peroxidase/química , Ácido gama-Aminobutírico/análise , Ampirona/química , Ascorbato Oxidase/química , Catalase/química , Cromatografia Líquida , Ensaios Enzimáticos/economia , Compostos Férricos/química , Ácido Glutâmico/química , Peróxido de Hidrogênio/química , Lycopersicon esculentum/química , Acoplamento Oxidativo , Proteínas Recombinantes , Streptomyces/enzimologia , Espectrometria de Massas em Tandem
4.
Chemosphere ; 240: 124951, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574445

RESUMO

A high demand exists in human biomonitoring studies for reliable and straightforward methods that generate data faster and simultaneously. Thus, the present study combines microextraction by packed sorbent (MEPS) and liquid chromatography coupled to mass spectrometry (LC-MS/MS) for simultaneous extraction and determination of various classes of endocrine-disrupting chemicals (EDCs), including parabens, benzophenones, bisphenols, and the antimicrobial, triclocarban in human urine samples. Optimized MEPS conditions were: i) MEPS sorbent (C18), ii) pH of sample (3), iii) volume of sample (250 µL), iv) number of draws-eject cycles (5) and (vi) desorption solvent conditions (100 µL of CH3OH:H2O 80:20 v/v). The calibration curves were linear over the selected ranges for all studied compound, with correlation coefficients higher than 0.99. The variation coefficient for precision was lower than 20% at lower concentrations and lower than 15% at the higher concentrations studied. The accuracy ranged from 90% to 118%. The proposed strategy affords several advantages over currently published approaches, including simplicity of operation and reduction of sample and solvent volumes and time for matrix clean-up. Moreover, the analytical performance of each MEPS cartridge remained stable over the analysis of at least 70 samples (RSD < 10%). Thus, the current procedure may be an interesting high-throughput alternative for large routine human biomonitoring studies. Urinary geometric mean concentrations of EDCs obtained in this study were close than those previously reported for Brazilian children.


Assuntos
Compostos Benzidrílicos/urina , Benzofenonas/urina , Carbanilidas/urina , Disruptores Endócrinos/urina , Parabenos/análise , Fenóis/urina , Brasil , Calibragem , Criança , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Humanos , Limite de Detecção , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
5.
Food Chem ; 305: 125450, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499291

RESUMO

A round robin comparison was performed in order to test the performance of a recently developed LC-MS/MS method for quantification of 6 folate forms. Eighty-nine samples representing the food groups of fruits, vegetables, legumes, cereals, dairy products, meat, and offal were analyzed by two LC-MS/MS methods and a microbiological assay (MA). A plant-origin deconjugase enzyme (Arabidopsis thaliana) for deconjugation of folates (PE-LC-MS/MS), or animal-origin deconjugase (rat serum and chicken pancreas) (AE-LC-MS/MS) was used in the LC-MS/MS methods, each in a single enzymatic step. In contrast, the MA involved tri-enzyme extraction including human plasma as a deconjugase. A significant bias of 17% lower and 25% higher results was found when PE-LC-MS/MS was compared to MA and AE-LC-MS/MS, respectively. The PE-LC-MS/MS provides fast quantification of various folate vitamers and total folate content, which could be a proper substitute to the currently standardized but imprecise and time-consuming microbiological assay in the future.


Assuntos
Ácido Fólico/análise , Espectrometria de Massas em Tandem/métodos , Animais , Galinhas , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Frutas/metabolismo , Humanos , Proteínas de Plantas/metabolismo , Ratos , Verduras/metabolismo , gama-Glutamil Hidrolase/metabolismo
6.
Food Chem ; 306: 125581, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606636

RESUMO

A comprehensive evaluation was conducted to compare the generation of antioxidative peptides produced by alcalase versus trypsin from Atlantic sea cucumber. The in vitro antioxidative peptides were sequenced by de novo sequencing using LC-MS/MS. Key constituent antioxidative amino acids (KCAAA), i.e., Cys, His, Met, Trp and Tyr in the peptides and the molecular interactions between peptides and myeloperoxidase (MPO, a mediator and marker of in vivo oxidative stress), were analyzed by in silico methods. Alcalase-produced protein hydrolysates showed 5-35% higher in vitro antioxidant activity than the trypsin-produced ones. UPLC analysis revealed the total amino acid composition in peptide fractions <2 kDa. Alcalase produced 35.4% of peptides with both KCAAA and potential MPO inhibitory activity, compared with only 30.3% for trypsin. A representative peptide sequence TEFHLL generated by alcalase had intense molecular interactions with MPO active site, predicting a capacity to inhibit in vivo oxidative stress.


Assuntos
Antioxidantes/metabolismo , Peptídeos/metabolismo , Pepinos-do-Mar/metabolismo , Subtilisinas/metabolismo , Tripsina/metabolismo , Animais , Cromatografia Líquida , Estresse Oxidativo , Espectrometria de Massas em Tandem
7.
Food Chem ; 305: 125505, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606693

RESUMO

Shalgam is a beverage which is produced by lactic acid fermentation of black carrot juice. Two commercial methods (traditional method - TM and direct method - DM) used to produce shalgams were compared with respect to their effects on the general compositions, bioactive phenolic compounds and antioxidant potentials for the first time. A total of 25 phenolic compounds comprising anthocyanins, flavonols, and phenolic acids were identified and characterized by LC-DAD-ESI/MSn. Cyanidin-3-xylosyl-galactoside and cyanidin-3-xylosyl-glucosyl-galactoside accounted for the highest amount of the total anthocyanins. Also, seven newly-identified anthocyanins including cyanidin 3-xylosyl-(caffeoyl-glucosyl)-galactoside, cyanidin 3-xylosyl-(p-hydroxybenzoyl-glucosyl)-galactoside, cyanidin 3-xylosyl-galactoside+vinylphenol, cyanidin 3-xylosyl-galactoside+vinylcatechol, cyanidin 3-xylosyl-(feruloyl-glucosyl)-galactoside+vinylcatechol, cyanidin 3-xylosyl-galactoside+ vinylguaiacol, cyanidin 3-xylosyl-(feruloyl-glucosyl)-galactoside+vinylguaiacol were found in the shalgam samples for the first time. Phenolic acids and flavonols of shalgam samples were studied for the first time. The major subclass of the chlorogenic acids was identified as 5-caffeoylquinic acid in the samples. Antioxidant capacities of the samples screened using ABTS and DPPH assays were in accordance with their total phenolic content. Principal component analysis (PCA) revealed clear discrimination between the two production methods (TM and DM). This study demonstrated that the DM provided higher phenolic and antioxidant potential than the TM in the shalgam samples.


Assuntos
Cromatografia Líquida , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Fenóis/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Daucus carota/química , Fenóis/química
8.
Food Chem ; 305: 125499, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606694

RESUMO

The quality of garlic is mainly attributed to organosulfur compounds that are the secondary metabolites of certain amino acids. Herein, a sensitive and rapid method for the simultaneous determination of 7 organosulfur compounds and 21 amino acids using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) was developed. Then the levels of these 28 compounds and allicin in garlic among 242 samples from 6 provinces in China were profiled with multivariate data analysis. The results showed that garlic was rich in organosulfur compounds and could be a good supplement for amino acids. Contents of 29 compounds varied greatly among the provinces. The multivariate data analysis demonstrated two major groups for all samples, indicating that the location has a significant influence on the metabolism of garlic. Besides, the compositional differences of garlic from 6 provinces and correlations for growing conditions and contents of components were also analyzed.


Assuntos
Aminoácidos/análise , Análise de Alimentos , Alho/química , Compostos de Enxofre/análise , Aminoácidos/química , Antioxidantes/análise , Antioxidantes/química , China , Cromatografia Líquida de Alta Pressão , Compostos de Enxofre/química , Espectrometria de Massas em Tandem
9.
Chemosphere ; 238: 124605, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31450107

RESUMO

A Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis was developed to extract thirteen synthetic musk compounds (SMCs: cashmeran, celestolide, phantolide, traseolide, galaxolide, tonalide, musk ambrette, musk xylene, musk ketone, musk tibetene, musk moskene, ethylene brassylate and exaltolide) and six ultraviolet-filters (UVFs: 2-ethylhexyl 4-dimethylaminobenzoate, 3-(4'-methylbenzylidene) camphor, 2-ethylhexyl 4-methoxycinnamate, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, benzophenone and drometrizole trisiloxane) from tomatoes. The proposed methodology was optimized: 2 g of freeze-dried tomato was extracted with 4 mL of water and 10 mL of ethyl acetate, adding 6 g of MgSO4 and 1.5 g of NaCl, then a dispersive solid-phase extraction was performed using 3 g of MgSO4, 300 mg of primary-secondary amino adsorbent (PSA) and 300 mg of octadecyl-silica (C18). Validation delivered recoveries between 81 (celestolide) and 119% (musk tibetene), with relative standard deviations <10%. The instrumental limit of detection varied from 0.02 (2-ethylhexyl 4-methoxycinnamate) to 3.00 pg (exaltolide and musk xylene). Regarding the method quantification limits, it ranged between 0.4 (celestolide) and 47.9 ng g-1 dw (exaltolide). The method was applied to different varieties of tomatoes (Solanum lycopersicum), revealing UVFs and SMCs between 1 and 210 ng g-1 dw. Higher concentrations were found for benzophenone (29-210 ng g-1 dw) and galaxolide (9-53 ng g-1 dw). The risk associated to the ingestion of contaminated tomatoes has also been estimated, showing that a potential health risk is unlikely.


Assuntos
Ácidos Graxos Monoinsaturados/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lycopersicon esculentum/química , Poluentes Químicos da Água/análise , Benzofenonas/análise , Benzopiranos/análise , Dinitrobenzenos/análise , Indanos/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Tetra-Hidronaftalenos/análise , Xilenos/análise
10.
Food Chem ; 305: 125482, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518838

RESUMO

To understand the effect of lipid degradation on Maillard formation of meaty flavors, initial reaction intermediates in model systems of glucose-glutathione with hexanal, (E)-2-heptenal, or (E,E)-2,4-decadienal were identified by HPLC-MS and by NMR. Besides Amadori compounds, hemiacetals and thiazolidines via addition of sulfhydryl to carbonyl or to the conjugated olefinic bond were found. Concentrations of all intermediates increased with reaction time while degradation of the intermediates with a glutathione moiety helped formation of thiazolidines with cysteinylglycine. The unsaturated aldehydes (E)-2-heptenal and (E,E)-2,4-decadienal exhibited high reactivity against glucose for glutathione, yielding higher levels of intermediate compounds than from glucose. Heating prepared intermediates reversibly released the original aldehydes, which caused various compounds formed by retro-aldol, oxidation, etc. to react with H2S and NH3. Among them, formation pathways including 3-nonen-2-one, 2-hexanoylfuran, and six dialkylthiophenes (e.g., 2-ethyl-5-(1-methylbutyl)thiophene) were proposed for the first time.


Assuntos
Aldeídos/química , Glucose/química , Glutationa/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Reação de Maillard , Oxirredução , Espectrometria de Massas em Tandem
11.
Food Chem ; 305: 125462, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31618694

RESUMO

The objectives of this research were to demonstrate the changes in isoflavone-aglycones, total phenolics, and biological properties (digestive enzyme inhibition; antioxidant) from six organs including leaves, leafstalks, roots, stems, seeds, and pods at different growth times of soybean plant. Three isoflavone-aglycones in microwave-assisted acid hydrolysis extracts were elucidated using UHPLC-ESI-Q-TOF-MS/MS and their contents exhibited remarkable differences in leaves (245.93-2239.33 µg/g), roots (854.96-4425.34 µg/g), and seeds (ND-2339.62 µg/g). Specifically, the collected samples on 15-Oct (leaves: 2239.33; seeds: 2339.62 µg/g) and 31-Aug (roots: 4425.34 µg/g) showed the highest isoflavone-aglycones, and daidzein was observed the most abundant component, comprising approximately 70%. Moreover, the inhibitions against α-glucosidase and α-amylase displayed the predominant effects in roots (89;91%) and leaves (81;85%) of samples on 31-Aug and 15-Oct at 300 µg/ml. The antioxidant activities on ABTS, DPPH, and hydroxyl radicals increased considerably with the increases of growth times in leaves and seeds, especially, ABTS showed the highest scavenging abilities: leaves (15-Oct;83%) > roots (31-Aug;75%) > seeds (15-Oct;68%). Therefore, our results suggest that soybean leaves, roots and seeds may be considered as excellent natural sources for nutraceuticals.


Assuntos
Antioxidantes/química , Glucosidases/metabolismo , Isoflavonas/análise , Micro-Ondas , Soja/química , Cromatografia Líquida de Alta Pressão , Glucosidases/antagonistas & inibidores , Hidrólise , Isoflavonas/metabolismo , Fenóis/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/metabolismo , Soja/crescimento & desenvolvimento , Soja/metabolismo , Espectrometria de Massas em Tandem/métodos
12.
Food Chem ; 308: 125650, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655477

RESUMO

This study aimed at investigating the formation and accumulation of 16 reactive aldehydes in clam (Ruditapes philippinarum) during oil frying in both the tissue and the oil using an HPLC-ESI-MS/MS methodology. After processing, the accumulation of acrolein, crotonaldehyde, pentanal, trans-2-hexenal, hexanal, trans, trans-2,4-heptadienal, heptanal, nonanal, trans, trans-2,4-decadienal and 4-hydroxy-2-nonenal was most noticeable in both fried clam and frying oil. Most of the aldehyde species showed a time- and temperature-dependent manner of formation and accumulation during frying due to continuous oxidative degradation under conditions employed. However, several species of aldehyde such as acrolein and trans-2-pentenal slightly decreased at higher temperatures and/or longer frying times, which may be due to the imbalance toward disappearance of aldehydes resulting from their evaporation under the extreme conditions. Presence of natural polyphenols in bamboo leaves significantly prevented the formation of aldehydes in both fried clam and frying oil due to their antioxidant activity (P < 0.05).


Assuntos
Aldeídos/química , Bivalves/química , Animais , Cromatografia Líquida de Alta Pressão , Culinária , Temperatura Alta , Oxirredução , Espectrometria de Massas em Tandem
13.
Food Chem ; 308: 125612, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31670192

RESUMO

A mixture of glucosamine (GlcN, 15% w/v) and different amino acids in 1:1 M ratio was incubated at 70 °C for 12 h. The resulting GlcN-amino acid caramels were analysed for α-dicarbonyl compounds, polyhydroxyalkyl pyrazines, heterocyclic compound and alkylimidazoles. All the analyses were performed by using HPLC-MS/MS followed by pooling the variables with principal component analysis (PCA). GlcN-Gly caramels generated the greatest amount of butterscotch aromatic compound diacetyl and polyhydroxyalkyl pyrazines (fructosazine and deoxyfructosazine). The potentially toxic heterocyclic compound, 5-hydroxymethylfurfural (HMF) was generated in greater amounts with the GlcN-Arg caramels. However, the toxic alkylimidazoles (4-MEI and THI) were not present in any of the GlcN-amino acid caramels. The results suggest that caramel with butterscotch aroma and bioactivity can be produced with GlcN-amino acid at 70 °C. The PCA performed discriminated the majority of the GlcN-amino acid combinations; GlcN-Gly and GlcN-Ser were best discriminated.


Assuntos
Aminoácidos/química , Glucosamina/química , Pirazinas/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
14.
Food Chem ; 306: 125582, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31622834

RESUMO

When α-tocopherol (α-Toc) exerts its antioxidative effect, a portion of α-Toc is converted to certain oxidation products. Although accumulation of such oxidation products is considered to cause a deterioration in the quality of foods, their distribution and generation in food samples have been still unknown. In this study, we tried to analyze α-Toc hydroperoxide (Toc-OOH) stereoisomers and tocopherylquinone (TQ) in extra virgin olive oil (EVOO) using liquid chromatography-tandem mass spectrometry. Photo-irradiation (5000 lx) to EVOO increased Toc-OOH stereoisomers but not TQ. In contrast, thermal oxidation (150 °C) of EVOO increased TQ but not Toc-OOH. We considered that the generation of Toc-OOH and TQ were due to the [4+2]-cycloaddition reaction and proton donation from the phenolic hydrogen, respectively. Our data and method would be helpful for understanding of α-Toc oxidation mechanisms in edible oil samples or the estimation of food quality.


Assuntos
Azeite de Oliva/química , Vitamina E/análogos & derivados , alfa-Tocoferol/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Oxirredução , Espectrometria de Massas em Tandem , Vitamina E/análise , Vitamina E/química , alfa-Tocoferol/análise , alfa-Tocoferol/química
15.
Food Chem ; 307: 125549, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648175

RESUMO

The aim of this study was to determine the influence of static and multi-pulsed hydrostatic pressure processing (HPP) treatments on the polyphenolic profile, oxidoreductase activity, colour, and browning index of carrot juice. Phenolic acids, flavonoids, lignans and other polyphenols were the predominant polyphenols detected with Triple-TOF-LC-MS/MS. The highest concentration of ferulic acid, didymin, dihydro-p-coumaric acid, sesaminol and matairesinol isomers were found among all the compounds detected. After HPP treatment, irrespective of the pressures applied, new simple polyphenols like oleuropein, 4-vinylsyringol, isocoumarin, and 4-hydroxybenzaldehyde were detected. Both phenomena could be attributed to the release of bounded phenolic compounds after applying HPP, as well as enzymatic degradation and/or condensation. The highest inactivation of polyphenoloxidase (PPO) enzymes (57%) was obtained at 300 MPa × 3 pulses, and peroxidase (POD) enzymes (31%) at 600 MPa working in static mode. Significant changes in the colour parameters and browning index were observed in all HPP-treated juices.


Assuntos
Catecol Oxidase/metabolismo , Daucus carota/química , Polifenóis/análise , Pressão Sanguínea , Cromatografia Líquida , Cor , Daucus carota/enzimologia , Espectrometria de Massas em Tandem
16.
J Sci Food Agric ; 100(2): 614-622, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31597198

RESUMO

BACKGROUND: Lonicera japonica Thunb is a common herb in East Asia. The flower buds are usually regarded as the traditional medicinal part, while leaves and stems are considered less valuable and receive little attention. This study compared the chemical constituents and anti-inflammatory effects of the different tissues in L. japonica Thunb for the first time. RESULTS: Thirty compounds were identified by ultra-performance liquid chromatography-photodiode detector-quadrupole / time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS/MS) analysis. Hydroxycinnamic acids, flavonoids, and iridoids were identified as the major components. The flower buds (FLJ), leaves (LLJ), and stems (SLJ) of L. japonica Thunb showed strong similarities in chemical components. The LLJ contained higher levels of hydroxycinnamic acids and flavonoids than the FLJ and SLJ. Furthermore, FLJ, LLJ, and SLJ exhibited potent anti-inflammatory activity in croton oil-induced ear edema and carrageenan-induced paw edema assays in mice. Moreover, FLJ, LLJ, and SLJ showed a cytoprotective effect on lipopolysaccharide- (LPS-) stimulated RAW 264.7 macrophages. Lipopolysaccharide-induced increases in nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) were suppressed by treatments of FLJ, LLJ, and SLJ, respectively. The LLJ possessed a stronger anti-inflammatory effect than the FLJ. CONCLUSION: Leaves and stems of L. japonica Thunb have chemical components and anti-inflammatory properties similar to flower buds, and may become alternative or supplementary sources of flower buds. © 2019 Society of Chemical Industry.


Assuntos
Anti-Inflamatórios/química , Edema/tratamento farmacológico , Lonicera/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Animais , Anti-Inflamatórios/administração & dosagem , Carragenina/efeitos adversos , Cromatografia Líquida de Alta Pressão , Edema/induzido quimicamente , Edema/genética , Edema/imunologia , Flavonoides/administração & dosagem , Flavonoides/química , Flores/química , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Folhas de Planta/química , Caules de Planta/química , Espectrometria de Massas em Tandem , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
17.
Food Chem ; 308: 125701, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669946

RESUMO

In this study, we found that glutaminase from Bacillus amyloliquefaciens could increase antioxidant activities of Gln-Cys mixture, demonstrated by the higher superoxide anion and DPPH radical scavenging activities, Fe2+-chelating and reducing power. According to UPLC-Q-TOF-MS/MS results, we identified γ-[Glu](n=1,2,3,4)-Cys in Gln-Cys mixture in the presence of glutaminase. The yields of γ-Glu-Cys (GC) and γ-Glu-γ-Glu-Cys (GGC) were 40.92% and 22.79% respectively, under the established optimum conditions: pH 10, 37 °C, 3 h, 0.1 mol/l Gln: 0.1 mol/l Cys = 1:1, and glutaminase at 0.1% (m/v). The antioxidant properties of GC, GGC, glutathione and Gln-Cys mixture in the presence of glutaminase were further compared and we found GC exhibited the highest superoxide anion and DPPH radical scavenging activities, and Fe2+-chelating and reducing power. Therefore, glutaminase caused the increase of antioxidant activity of Gln-Cys mixture and might be attributed to GC which was synthesized by glutaminase via transpeptidation, and GC has the potential to be used in food and nutraceutical applications as an antioxidant peptide.


Assuntos
Antioxidantes/metabolismo , Bacillus amyloliquefaciens/enzimologia , Dipeptídeos/metabolismo , Glutaminase/metabolismo , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
18.
Food Chem ; 307: 125526, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648172

RESUMO

Effective management of mycotoxins rely on stringent regulation and routine surveillance of food/feed commodities via efficient analysis, hence the continuous need for improved methods. The present study developed, optimized and validated a modified pressurized hot water extraction (PHWE) method for the simultaneous extraction of multi-mycotoxins from maize and subsequent quantification on LC-MS/MS. The PHWE system was modified using ethanol (EtOH) as a cosolvent, while a numerical modelling approach, the central composite design (CCD), was adopted for the optimization of the extraction conditions. Using the optimized method, it was possible to effectively extract and quantify 15 different mycotoxins from maize in a single step with satisfactory linearities (0.986-0.999), recoveries (14-124%) and other associated method validation parameters. Further efficacious application of the method to real samples re-affirmed the prospects of PHWE as a suitable, cost-effective and greener alternative to traditional methods of mycotoxin extraction.


Assuntos
Micotoxinas/análise , Água/química , Zea mays/metabolismo , Cromatografia Líquida de Alta Pressão , Temperatura Alta , Limite de Detecção , Micotoxinas/isolamento & purificação , Pressão , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
19.
Food Chem ; 307: 125515, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648177

RESUMO

This study evaluated the polyphenol profile and the antioxidative properties of Plinia trunciflora (O. Berg) Kausel fruits. Folin-Ciocalteau and pH-jumping methods indicated that these berries are a major source of antioxidant polyphenols (1201.05 mg GAE/100 g FW), particularly anthocyanins. HPLC-DAD-ESI-MS/MS analysis identified cyanidine glycosides as the main components. Flavon-3-ols and hydrolysable-tannins were also found. CAA assay showed that extracts of P. trunciflora fruits prevent lipid peroxidation in HepG2 cells with higher efficacy than other colourful fruits (CAA50 935.25 mg FW/mL cell medium). Moreover, our results suggested that the observed antioxidant protection involve both redox active properties of P. trunciflora components, as measured by ABTS, DPPH and FRAP assays, and upregulation of the genes coding for the antioxidant enzymes MnSOD and GPx, as evaluated by qRT-PCR. Collectively, our data provided evidence on the potential of P. trunciflora fruit as a very rich source of natural antioxidant molecules.


Assuntos
Antioxidantes/metabolismo , Suplementos Nutricionais/análise , Myrtaceae/química , Compostos Fitoquímicos/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Células Hep G2 , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Myrtaceae/metabolismo , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/análise , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Espectrometria de Massas em Tandem , Regulação para Cima/efeitos dos fármacos
20.
Zhongguo Zhong Yao Za Zhi ; 44(20): 4529-4537, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872642

RESUMO

Ultra-fast performance liquid chromatography-mass spectrometry( UFLC-MS/MS) was used to study the anti-inflammatory active ingredient of Millettia pachyloba,6-methoxy-8,8-dimethyl-3-( 2,4,5-trimethoxyphenyl)-4 H,8 H-pyrano[2,3-f]chromen-4-one( HN-1),in liver microsomes of rats,mice,rhesus monkeys,Beagle dogs and humans metabolic stability,and compare the metabolic differences between different species. The metabolic phenotype in human liver microsomes was determined by chemical inhibitor method. Using UPLC-Q-TOF-MS/MS detection method,the in vitro metabolites of various liver microsomes were preliminarily inferred by comparing the samples incubated for 0 min and 60 min in vitro. The metabolites of HN-1 in SD rats were presumed by comparing feces,urine,plasma blanks and samples after administration. The results showed that the metabolism of HN-1 in various liver microsomes was stable,and the metabolic properties of dog and human liver microsomes were the closest. It is mainly catabolized by CYP1 A1,CYP2 D6 and CYP3 A4 isoenzymes in human liver microsomes. The metabolites of HN-1 in vitro and in vivo,including 3 in vitro metabolites and5 in vivo metabolites,were preliminarily estimated. The results laid the foundation for further pharmacological studies of HN-1.


Assuntos
Medicamentos de Ervas Chinesas , Millettia , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Cães , Humanos , Camundongos , Microssomos Hepáticos , Ratos , Ratos Sprague-Dawley
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