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1.
SAR QSAR Environ Res ; 31(10): 761-784, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32867537

RESUMO

The free COOH group of conventional NSAIDs is a structural feature for non-selective cyclooxygenase (COX) inhibition and the molecular cause of their gastrointestinal (GI) toxicity. In this context, an in house database of synthesizable ester prodrugs of some well-known NSAIDs was developed by combining their -COOH group with -OH of a newly identified antioxidant 4-(1H-benzo[d]imidazol-2-yl)phenol (BZ). The antioxidant potential of BZ was unveiled through in silico PASS prediction and in vitro/in vivo evaluation. The in house database of NSAIDs-BZ prodrugs was first subjected to screening with our previously reported pharmacophore models of hCES1 (AAHRR.430) and hCES2 (AHHR.21) for determining hydrolytic susceptibility. Biotransformation behaviour of screened prodrugs was then assessed by using QM/MM and sterimol parameterization, followed by ADMET calculations to predict the drug likeness. On the basis of in silico results, five prodrugs were duly synthesized and the best three were subject to the in vivo evaluation for their anti-inflammatory, analgesic, antioxidant activities, and ulcerogenic index. Among these prodrugs, BN2 and BN5 displayed better anti-inflammatory and analgesics potential in comparison to their parent drugs. All the prodrugs were found to be gastro sparing in the rat model and significantly improved the levels of oxidative stress biomarkers in both blood plasma as well as gastric homogenate.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Imidazóis/química , Fenóis/química , Pró-Fármacos/síntese química , Relação Quantitativa Estrutura-Atividade , Simulação por Computador
2.
Ecotoxicol Environ Saf ; 204: 111093, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32805502

RESUMO

Phenolic Endocrine Disrupting Chemicals (EDCs) have drawn more and more interest due to their prevalence and persistence in aquatic environment. To study the adsorption of various phenolic EDCs on river sediments under natural conditions, we first sought to analyze the distribution characteristics of phenol and bisphenol A (BPA) in sediment from the Bahe River. The static adsorption experiments contained either single- or dual-contaminant of phenol and/or BPA in the system; they were conducted to characterize the adsorption of these two pollutants in the surface sediments and the main factors affecting the adsorption processes of the dual-contaminant system, including particle size, humic acid (HA) concentration, pH, and temperature. Results showed that in certain seasons, there was a significant correlation between the levels of phenol and BPA in Bahe sediments. When comparing the adsorption behaviors of phenol and BPA on sediments in single- and dual-contaminant systems, we found that the phenol adsorption behavior varied, while that of BPA remained consistent across the different systems. Moreover, different effects were observed with regards to a single factor and the interaction of multiple factors on the adsorption of pollutants. Of the four single factors, only HA concentration had a significant effect on the phenol adsorption in sediment. When considering the interaction of multiple factors, the interaction between HA concentration and temperature significantly promoted the adsorption of phenol. The influence of factors on the adsorption of BPA was in the following order: particle size > HA concentration > pH > temperature. Particle size significantly inhibited BPA adsorption in the sediment, while the interaction between particle size and pH increased BPA adsorption.


Assuntos
Compostos Benzidrílicos/química , Fenol/química , Fenóis/química , Poluentes Químicos da Água/química , Adsorção , Disruptores Endócrinos/análise , Poluentes Ambientais , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Fenóis/análise , Rios/química , Temperatura , Poluentes Químicos da Água/análise
3.
PLoS One ; 15(8): e0238061, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32846429

RESUMO

The method of non-aqueous conductivity titration (NACT) of organic weak acids was applied to quickly and accurately determine the phenolic-hydroxyl and carboxyl-groups contents in humic acid. By varying the pH of the humic-acid sample, the concentration of the titrant, and the nitrogen-gas flow rate, the optimal titration conditions were determined to be a sample pH of 4, titrant concentration of 0.05 mol/L, and nitrogen-gas flow rate of 80 mL/min. Applying the detection method to p-hydroxybenzoic acid showed that its phenolic-hydroxyl content was 758.82±111.76 cmol/kg and carboxyl content was 744.44±51.11 cmol/kg. The theoretical phenolic-hydroxyl and carboxyl-groups contents of the p-hydroxybenzoic acid were 723.96 cmol/kg respectively, indicating that the method can accurately quantify the carboxyl and phenolic-hydroxyl groups in the sample. The NACT was used to measure the phenolic-hydroxyl and carboxyl-groups contents in humic acid quickly and accurately. In addition, 29 humic acid samples from 8 provinces of China covering the main humic-acid producing areas were collected and analyzed for acidic-groups content using the reported method.


Assuntos
Técnicas Eletroquímicas/métodos , Substâncias Húmicas/análise , China , Condutividade Elétrica , Eletrodos , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/análise , Fenóis/química , Solo/química
4.
Food Chem ; 332: 127415, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619945

RESUMO

This study aimed to investigate the combined effect of storage at 4 °C (10-days) and in vitro gastrointestinal digestion on the phytochemical profile of red beet (Beta vulgaris) and amaranth (Amaranthus sp.) microgreens. The untargeted profiling based on UHPLC-QTOF metabolomics allowed annotating 316 compounds, comprising mainly polyphenols and lipids. An impact of storage on the total phenolic content (TPC) was observed, with a maximum increase at 10-days of storage for both red beet (+1.3-fold) and amaranth (+1.1-fold). On the other hand, in vitro digestion of both red beet and amaranth microgreens produced a significant increase in TPC (36-88%), CUPRAC (27-40%), DPPH (6-43%), and BC (41-57%) to reach the maximum at 10 days of storage. Tyrosinase inhibitory potential also decreased following digestion. The combination of biochemical changes occurring in microgreen immature plants (likely in response to the harvest stress) with changes during digestion, determined the actual functional value of microgreens.


Assuntos
Amaranthus/química , Beta vulgaris/química , Metabolômica/métodos , Amaranthus/metabolismo , Beta vulgaris/metabolismo , Cromatografia Líquida de Alta Pressão , Temperatura Baixa , Digestão , Análise Discriminante , Armazenamento de Alimentos , Análise dos Mínimos Quadrados , Espectrometria de Massas , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Fenóis/química , Fenóis/metabolismo
5.
Food Chem ; 333: 127501, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32682230

RESUMO

Pomegranate seed oil is valuable source of bioactive compounds with health-beneficial effects, but it is sensitive to oxidation due to high content of PUFA. In order to improve stability of pomegranate seed oil, the influence of natural antioxidant (0.1% pomegranate peel extract) and a combination of synthetic antioxidant (0.01% butylhydroxytoluene) and pomegranate peel extract (0.05%) was investigated. The oxidation process was followed by monitoring fatty acid composition and measuring the quality and stability parameters of oil (acid value, peroxide value, anisidine value and thiobarbituric acid reactive substances value) during storage for 12 days at 65 °C. Furthermore, total phenolic content and DPPH radical scavenging activity was measured. Pomegranate peel extract as well as a combination of pomegranate peel extract and BHT can have a significant positive impact (P < 0.05) on improvement of the quality and stability parameters of pomegranate seed oil. Furthermore, such activity was better than BHT used alone.


Assuntos
Extratos Vegetais/química , Óleos Vegetais/química , Romã (Fruta)/química , Antioxidantes/química , Hidroxitolueno Butilado/química , Frutas/química , Oxirredução , Fenóis/química , Substâncias Reativas com Ácido Tiobarbitúrico/química
6.
Food Chem ; 333: 127502, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683257

RESUMO

The aim of this study was to evaluate the effectiveness of the use of ethanol, ultrasound and/or vacuum as a pretreatment to melon drying. Eight types of pretreatments were performed in which samples were immersed in ethanol solutions with different concentrations (50% and 100%) using four treatment conditions: immersion, immersion with ultrasound (US), with vacuum (VC) and with ultrasound and vacuum (USVC). Drying was performed at 60 °C and five different semi-theoretical drying mathematical models were examined to characterize the drying curves, and quality analyses were carried out. The condition that obtained the lower drying time was using the US pretreatment in 100% ethanol solution. Drying caused a diminution of bioactive compounds and influenced color parameters. However, the samples immersed in 50% ethanol solution and dried obtained minor losses of total phenolics, total carotenoids, and ascorbic acid contents.


Assuntos
Cucurbitaceae/química , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Ácido Ascórbico/análise , Carotenoides/química , Cor , Cucurbitaceae/efeitos dos fármacos , Dessecação , Conservação de Alimentos/instrumentação , Frutas/química , Frutas/efeitos dos fármacos , Fenóis/química , Vácuo
7.
Food Chem ; 333: 127525, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683262

RESUMO

The consumption of halophytes as healthy gourmet food has increased considerably in the past few years. However, knowledge on the nutritional profile of domesticated halophytes is scarce and little is known on which cultivation conditions can produce plants with the best nutritional and functional properties. In this context, Salicornia ramosissima J. Woods was cultivated in six different salt concentrations, ranging from 35 to 465 mM of NaCl. Both the nutritional profile, the antioxidant capacity, and microbial quality of the produced plants were evaluated including minerals and vitamins. Salt has a marked effect on growth, which decreases for salinities higher than 110 mM. Nonetheless, plants cultivated with intermediate levels of salinity (110 and 200 mM) revealed better antioxidant status with higher amounts of phenolic compounds. Overall, results from this paper indicated that soilless culture systems using low-intermediate salinities produces S. ramosissima plants fit for commercialization and human consumption.


Assuntos
Antioxidantes/química , Chenopodiaceae/química , Cloreto de Sódio/química , Bactérias/isolamento & purificação , Carotenoides/análise , Chenopodiaceae/crescimento & desenvolvimento , Chenopodiaceae/microbiologia , Cromatografia Líquida de Alta Pressão , Fungos/isolamento & purificação , Valor Nutritivo , Fenóis/química , Vitaminas/análise
8.
Chem Biol Interact ; 329: 109202, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32717189

RESUMO

Triple-negative breast cancer (TNBC) is highly metastatic and lacks effective therapeutic targets among several subtypes of breast cancer. Cancer metastasis promotes the malignancy of TNBC and is closely related to the poor prognosis of the TNBC patients. We aim to explore novel agents that effectively inhibit cancer metastasis to treat TNBC. In our study, 2-Methoxy-5((3,4,5-trimethosyphenyl)seleninyl) phenol (SQ), a CA-4 analogue, could inhibit cell motility and invasion in MDA-MB-231 cells, and the mechanism is closely associated to the inhibition of epithelial-to-mesenchymal transition (EMT). Meanwhile, SQ significantly inhibited the expression and secretion of vascular endothelial growth factor (VEGF) in MDA-MB-231 cells. Moreover, the conditioned medium from SQ-treated MDA-MB-231 cells significantly inhibited the motility and invasion of human umbilical vein endothelial cells (HUVECs), which was correlated with the inhibition of EMT process in HUVECs. In addition, exogenous application of VEGF reversed the occurrence of EMT in HUVECs which stimulated by conditioned medium from SQ-treated cells. Furthermore, SQ inhibited vasculogenic mimicry (VM) formation in MDA-MB-231 cells, which was associated with VE-cadherin and EphA2 down-regulation. This study indicates that SQ inhibits MDA-MB-231 cell metastasis through suppressing EMT and VEGF, thereby implicating this compound might be a potential therapeutic agent against metastatic TNBC.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Fenóis/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Regulação para Baixo/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Compostos Organosselênicos/química , Fenóis/química , Receptor EphA2/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Fator A de Crescimento do Endotélio Vascular/genética
9.
Food Chem ; 332: 127429, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645678

RESUMO

Thermal processing is a traditional method for processing hawthorn into food or medicine. In this study, the compositions of free and bound phenolic compounds in raw hawthorn were analyzed by ultra-performance liquid chromatography quadrupole-time of flight mass spectrometry, and the effect of thermal processing on phenolics and antioxidant activity was determined. Among the phenolics identified in unheated hawthorn, 26 were soluble, while only 10 were insoluble-bound. Thermal processing caused a significant reduction in total soluble phenolics content, but an increase in total insoluble-bound phenolics (p < 0.05). Procyanidin B2 and epicatechin showed the largest decreases in content, and were not detected in well-cooked hawthorn. The antioxidant activity also clearly decreased, with the chlorogenic acid, procyanidin B2, hyperoside, and isoquercetin contents correlating significantly (p < 0.05) with antioxidant activity. In general, the effect of thermal processes on phenolics and antioxidant activity was dependent on the types of phenolics and processing conditions.


Assuntos
Antioxidantes/química , Crataegus/química , Manipulação de Alimentos/métodos , Fenóis/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida , Temperatura Alta , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação
10.
Food Chem ; 331: 127326, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32674069

RESUMO

A precise and accurate GC-MS/MS method with ng L-1 LLOQs, acceptable recovery (78-107%) and estimated uncertainty (U > 20%, except at LLOQ) was developed following the Eurachem guidelines. We established the migration and stability of twelve bisphenols in two food simulants (C: 20% ethanol, and B: 3% acetic acid) from beverage cans (n = 16) and reusable metal and plastic sports bottles (n = 51). Bisphenols were stable in dried (eight weeks, -20 °C) and derivatised extracts (seven days, 21 °C). Cans leached BPA (<5865 ng L-1), three BPF isomers (8.2-1286 ng L-1) and BPAP (1.6 ng L-1), while bottles leached BPA (<222 ng L-1) and BPF, BPE, BPB and BPZ (1.1-4.6 ng L-1). Simulant C was more aggressive than simulant B, and concentrations of bisphenols decreased with consecutive exposure to simulants. Levels of BPA migrating from cans did not exceed the specific migration limits.


Assuntos
Compostos Benzidrílicos/química , Bebidas/análise , Reutilização de Equipamento , Embalagem de Alimentos , Fenóis/química , Esportes , Contaminação de Alimentos/análise
11.
Food Chem ; 332: 127390, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603922

RESUMO

Revalorization of mushroom by-product (stalks of A. bisporus) by extracting its components is proposed. The extraction kinetics at 25 °C of ergosterol, phenolic compounds and antioxidant activity by mechanical agitation (at 130 rpm) and ultrasound assistance (at 182 and 321 W/L) in 70 and 96% v/v ethanol/water solutions during 30 min were evaluated and satisfactorily modelled, using the Weibull model (mean relative error ≤ 7.8%). The effect of the ethanol concentration was high in the ergosterol extraction yield (2 times higher yields in 96% than in 70%) but slight in those of phenolic compounds and antioxidant activity. Ultrasound assistance promoted considerable yield increases (up to 2 times higher in ergosterol, 46% in phenolic compounds and 25% in antioxidant activity) depending on the ethanol concentration and ultrasound power density. The residues after extraction were characterized and constituted a potential source of high value polysaccharides as ß-glucans (average 12.2 ± 1.7g/100 g dm).


Assuntos
Agaricales/química , Antioxidantes/química , Ergosterol/química , Extração em Fase Sólida/métodos , beta-Glucanas/química , Agaricales/metabolismo , Antioxidantes/isolamento & purificação , Ergosterol/isolamento & purificação , Etanol/química , Modelos Teóricos , Fenóis/química , Sonicação
12.
Food Chem ; 332: 127382, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619943

RESUMO

Sea buckthorn (Hippophaë rhamnoides L.) berries have high biological value as a rich source of phenolic compounds, fatty acids and vitamins A, C, E. Due to the high organic acid content and sour taste, the fruits are rarely used in juice production. Therefore, the study aimed to determine the metabolic activity of Lactobacillus plantarum, Lactobacillus plantarum subsp. argentoratensis and Oenococcus oeni strains along with the dynamics of changes in organic acids, sugars, phenolic compounds, and antioxidant activity during 72-h fermentation of 100% sea buckthorn and mixed with apple (1:1) juices. The strongest malolactic conversion was in mixed juices (to 75.0%). The most efficient strains were L. plantarum DSM 10492, 20174 and 6872. L. plantarum strains caused an increase in flavonols and antioxidant activity of sea buckthorn-apple juices. The results can be used to select conditions and strains in industrial-scale fermentation, to produce novel sea buckthorn products and increase their consumption.


Assuntos
Antioxidantes/química , Sucos de Frutas e Vegetais/análise , Ácido Láctico/metabolismo , Malatos/metabolismo , Fenóis/metabolismo , Açúcares/metabolismo , Fermentação , Flavonóis/química , Flavonóis/metabolismo , Frutas/química , Frutas/metabolismo , Hippophae/química , Hippophae/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/metabolismo , Malus/química , Malus/metabolismo , Oenococcus/crescimento & desenvolvimento , Oenococcus/metabolismo , Fenóis/química
13.
Food Chem ; 330: 127244, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32526652

RESUMO

The aim of this study is to simultaneously evaluate anti-oxidative and anti-inflammatory activities of the hop extracts by different solvents. Hop water extract (HWE) and hop ethanol extracts (HEEs) were prepared by extracting hop pellets with hot water at 90 °C and ethanol solutions (55%, 75%, and 95%), respectively. Bioactive compound such as α-acid, ß-acid, total phenolic, and total flavonoid contents were determined. All the HEEs showed higher anti-oxidative activities than the HWEs. The HEEs showing the highest anti-oxidative activities are different in the experiments with different free radicals. For anti-inflammatory activities, both the HWE and HEEs decreased NO productions. HWE decreased TNF-α and IL-6 secretion but showed no effect on IL-1ß, while HEEs decreased IL-1ß and IL-6 secretion but increased TNF-α secretion. Except for TNF-α secretion, the HEEs showed higher anti-inflammatory activities than the HWE. Future work is to explore the possible mechanism to improve the ethanol extraction procedure.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Humulus/química , Extratos Vegetais/química , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Camundongos , Oxirredução , Fenóis/química , Extratos Vegetais/farmacologia
14.
Food Chem ; 329: 127157, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32504918

RESUMO

The processing and digestive stability of ethanolic extracts from four Thai rice bran varieties, namely Khao Dawk Mali 105, Hom Nil, Kiaw Ngu, and Leum Pua, were assessed by applying different thermal and pH conditions, as well as in vitro gastrointestinal digestion models. High-performance liquid chromatography, Folin-Ciocalteu analysis, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP) assays were used to determine the chemical composition, total phenolic content (TPC), and antioxidant activity. Thermal treatment at 100 °C for 15 min induced the degradation of phenolic components and TPC, whereas the antioxidant activities measured by DPPH and FRAP assays remained stable after the heat treatment. Higher phenolic content and antioxidant activity values were observed in the extracts incubated at acidic pH levels of 3 and 5. After simulated digestion, all extracts exhibited the decrease of phenolic compounds and anthocyanin contents, as well as antioxidant activities.


Assuntos
Antocianinas/química , Antocianinas/farmacocinética , Oryza/química , Fenóis/química , Fenóis/farmacocinética , Antocianinas/análise , Antioxidantes/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Digestão , Etanol/química , Calefação , Concentração de Íons de Hidrogênio , Fenóis/análise , Extratos Vegetais/química , Tailândia
15.
J Chromatogr A ; 1623: 461192, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505285

RESUMO

An imidazolium ionic-liquid-modified phenolic resin (ILPR) was synthesized using 3-aminophenol as a functional monomer, glyoxylic acid as a green cross-linker, and polyethylene glycol 6000 as a porogen. The obtained ILPR showed better extraction of benzoylurea plant hormones thidiazuron and forchlorfenuron than the unmodified phenolic resin because the imidazolium IL provides more interaction modes with the analytes. ILPR, as a tailored adsorbent for solid-phase extraction, was coupled with high-performance liquid chromatography (ILPR‒SPE‒HPLC) for the simultaneous determination of thidiazuron and forchlorfenuron in cucumbers. Good linearity of the ILPR‒SPE‒HPLC method was obtained, ranging from 0.0100 to 5.00 µg g-1 with a correlation coefficient (r) ≥ 0.9999. The recoveries of spiked samples ranged from 91.4% to 100.7% with a relative standard deviation of ≤ 6.0%.


Assuntos
Cucumis sativus/química , Formaldeído/química , Imidazóis/química , Líquidos Iônicos/química , Fenóis/química , Compostos de Fenilureia/isolamento & purificação , Polímeros/química , Piridinas/isolamento & purificação , Extração em Fase Sólida/métodos , Tiadiazóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Formaldeído/síntese química , Líquidos Iônicos/síntese química , Cinética , Fenóis/síntese química , Polímeros/síntese química , Reprodutibilidade dos Testes
16.
J Chromatogr A ; 1623: 461197, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505286

RESUMO

Trifluoromethyl covalent organic framework (CF3-COF) is facilely synthesized at room temperature using for solid-phase microextraction (SPME). The CF3-COF coating displays an improved extraction performance for per- and polyfluorinated alkyl substances (PFASs) comparing to amorphous polymer coating, non-contained fluorine covalent organic framework coating and commercially available SPME coating. The fluorine affinity of trifluoromethyl in CF3-COF for PFASs is demonstrated using the density functional theory calculation. Following the microextraction with CF3-COF-coated fiber, the targeted PFASs are eluted with 1 mL acetonitrile and quantified by ultrahigh performance liquid chromatography tandem mass spectrometry. The low limits of detection are 0.1-0.7 pg g-1 for milk and 0.2-0.8 pg g-1 for milk powder, suggesting the outstanding sensitivity. The precision for the method ranges between 2.9 and 9.9%. The fiber-to-fiber repeatability is in the range of 4.2-9.5%. Under the optimum conditions, the relative recoveries are 91.0-110% with RSDs ≤ 10% for milk and 89.8-111% with RSDs ≤ 10% for milk powder.


Assuntos
Hidrocarbonetos Halogenados/isolamento & purificação , Estruturas Metalorgânicas/química , Leite/química , Microextração em Fase Sólida/métodos , Adsorção , Animais , Citrullus/química , Sucos de Frutas e Vegetais/análise , Glioxal/química , Concentração de Íons de Hidrogênio , Estruturas Metalorgânicas/síntese química , Fenóis/química , Reprodutibilidade dos Testes , Resinas Sintéticas/química , Ureia/química
17.
Int J Food Microbiol ; 328: 108664, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32474229

RESUMO

To control Pseudomonas and Shewanella as important psychrotrophic spoilage bacteria in fish meat, we used ethanolic extracts of oregano (Origanum vulgare subsp. vulgare) and nettle (Urtica dioica), with phytochemical characterisation of the extracts and their bioactive compounds. Liquid chromatography coupled with photodiode array detection and electrospray ionisation-mass spectrometry was used for qualitative compositional determination of the extracts. Four main compounds were identified in the oregano extract, with rosmarinic acid the most abundant, followed by three glycosylated phenolics, one of which is reported for the first time in O. vulgare: 4'-O-ß-d-glucopyranosyl-3',4'-dihydroxybenzyl-4-hydroxybenzoate. Six main compounds were identified in the nettle extract, as caffeoylmalic acid and five flavonoid glycosides. These oregano and nettle ethanolic extracts showed in-vitro antimicrobial activities against selected Pseudomonas and Shewanella strains in broth and fish meat homogenate when evaluated at two inoculum concentrations. The antimicrobial activities were more pronounced for the nettle extract at the lower inoculum concentration, and for both the Shewanella strains. Growth inhibition in the fish meat homogenate was evaluated at 3.13 mg/mL and 1.56 mg/mL at 5 °C. Again, the nettle extract showed greater antimicrobial activity, which was seen as the lowest maximum growth rate, followed by the oregano extract, which was inhibitory only at 3.13 mg/mL. Finally, the extracts were applied to fish meat that was then stored at 5 °C for 9 days. Evaluation here was for the counts of the mesophilic, psychrotrophic, Pseudomonas and H2S producers. These confirmed the better antimicrobial effects of the nettle extract, especially against the H2S-producing bacteria, which included Shewanella. Both of the extracts were rich in glycosides of flavonoids and phenolic acids. The enzymatic activities of the Pseudomonas and Shewanella spoilage bacteria and their actions on the phenolic glycosides from natural sources will be further investigated.


Assuntos
Doenças dos Peixes/tratamento farmacológico , Origanum/química , Extratos Vegetais/farmacologia , Pseudomonas/efeitos dos fármacos , Shewanella/efeitos dos fármacos , Urtica dioica/química , Animais , Ácidos Cafeicos/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologia , Peixes/microbiologia , Flavonoides , Microbiologia de Alimentos , Hidroxibenzoatos/farmacologia , Malatos/farmacologia , Fenóis/química , Alimentos Marinhos/microbiologia , Espectrometria de Massas por Ionização por Electrospray
18.
Chemosphere ; 258: 127371, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554020

RESUMO

Fungal laccase has aroused great concern in rapidly removing estrogens because of its ability to accelerate humification and oligomerization. Here, the effect of two humic acids (HAs) on the reaction kinetics and products distribution of 17α-ethynylestradiol (EE2) in laccase-initiated humification and coupling was systematically elucidated. Laccase from Trametes versicolor exhibited over 98.3% removal rate for EE2 at pH 5.0 within 120 min, while HAs invariably restrained EE2 transformation by competing with target-substrate for the enzymatic catalytic center. EE2 removal followed pseudo-first-order kinetics, and the rate constant was decreased markedly with increasing concentration of two HAs (0-60 mg L-1). Additionally, laccase heightened the aromaticity and humification degrees (A250 nm/A365 nm ratio) of HAs probably due to the formation of new humic polymers such as (HA)m and/or (HA)m-(EE2)n (m and n represent the number of HA and EE2 units, respectively). Three major EE2 oligomers were identified, in accordance with a mechanism involving the phenoxy radical-driven polymerization to yield a wide variety of self-coupling products. Notably, HAs diminished the extent of EE2 self-coupling but aggrandized the cross-coupling between EE2 and HAs, and the inhibition degree of EE2 self-coupling increased with the concentration of HAs. One major reason is EE2 could be covalently incorporated into humic molecules to produce (HA)m-(EE2)n cross-coupling products via radical-caused C-C, C-O-C, and/or C-O-C bonds, thereby reducing EE2 self-oligomerization. These findings highlight that HAs play a vital role in the fungal laccase-induced humification and oligomerization of EE2, which obviously alter the geochemical fate and transport of EE2 in natural aquatic ecosystems.


Assuntos
Etinilestradiol/química , Substâncias Húmicas/análise , Lacase/química , Trametes/enzimologia , Poluentes Químicos da Água/química , Catálise , Ecossistema , Estrogênios , Etinilestradiol/análise , Cinética , Modelos Químicos , Fenóis/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
19.
Food Chem ; 330: 127197, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540521

RESUMO

Plants have been traditionally used for the treatment of different types of illness, due to biomolecules with recognised benefits. Rosaceae family is used in traditional Galician medicine. The following plants Agrimonia eupatoria, Crataegus monogyna, Filipendula ulmaria, Geum urbanum, Potentilla erecta and Rosa canina are usually found in treatments. The aim of this study is to perform an ethnobotanical review about the bioactive compounds of these plants and their different bioactivities, both studied in vitro and in vivo. The nature of the bioactive compounds is varied, highlighting the presence of different phenolic compounds, such as phenolic acids, flavonoids or tannins. Understanding the beneficial effects of the administration of the whole plant or target tissues from A. eupatoria, C. monogyna, F. ulmaria, G. urbanum, P. erecta and R. canina as well as those from their individual compounds could lead to the development of new drugs based on the use of natural ingredients.


Assuntos
Rosaceae/química , Desenvolvimento Industrial , Fenóis/química
20.
Food Chem ; 330: 127211, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540527

RESUMO

With the current agro-food industry demands for more environmentally-friendly production, the use of natural antifungal compounds extracted by emerging technologies led to a sustainable alternative to control microorganisms. Therefore, the present work aimed to: (i) determine antifungal activity against Colletotrichum gloeosporioides and Penicillium italicum of jackfruit leaf extracts obtained by different methods, and (ii) identify compounds by HPLC-DAD-ESI-MS. Microwave (MAE), high-hydrostatic pressure (HHP) and ultrasound (UAE) assisted extractions were tested, followed by fractionation with different polarity solvents. The concentration of total soluble phenols (TSP), tannins (TT) and flavonoids (TF) were determined. Differences not only in the amounts of extracted phytochemicals were found but in the antifungal properties (MAE against P. italicum and HHP against C. gloeosporioides at 5 mg/ml) as well as in the chemical composition determined by HPLC-MS. These results suggest the possible application of jackfruit leaf extracts as a suitable postharvest antifungal treatment.


Assuntos
Antifúngicos/química , Artocarpus/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Antifúngicos/farmacologia , Colletotrichum/efeitos dos fármacos , Flavonoides/química , Penicillium/efeitos dos fármacos , Fenóis/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Taninos/química
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