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1.
Food Chem ; 321: 126693, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247183

RESUMO

BACKGROUNDS: Polymers, widely existing in food or dietary materials, have been attracting researchers, facing challenges, and needing effective strategies on targeted characterization in complex matrixes. METHODS: A modified data filtering strategy (including locating with drift time and m/z ranges, multiple mass defect filtering, validating MS information, and evaluating MS/MS spectra) was developed and applied for procyanidins in the grape seed extracts (GSE) using drift tube ion mobility-mass spectrometry. The procyanidin ions' trendlines were predicted by multi-model regression. Their collision cross-sections (CCSs) were calculated using single-field methods. RESULTS AND DISCUSSION: Totally, 769 CCSs belonging to 686 procyanidins with polymer degrees at 1-15 were characterized. The exponent regression was the most reasonable model (r2 ≥ 0.9379) to reveal the trendlines. The change tendency of CCSs with their polymer degrees, charge states, and linkage types were investigated. CONCLUSION: This study provided an innovative strategy for targeted characterization of polymers in complex matrixes.


Assuntos
Biflavonoides/análise , Biflavonoides/química , Catequina/análise , Catequina/química , Extrato de Sementes de Uva/análise , Espectrometria de Mobilidade Iônica/métodos , Espectrometria de Mobilidade Iônica/estatística & dados numéricos , Proantocianidinas/análise , Proantocianidinas/química , Análise de Regressão , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
2.
Food Chem ; 322: 126767, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32330787

RESUMO

Due to the lack of innovative valorization strategies, berry pomaces are a poorly utilized as a cheap source of valuable nutrients and phytochemicals. An effective biorefining scheme was developed to recover functional components from lingonberry pomace by consecutive supercritical CO2 (SFE-CO2), pressurized liquid (PLE) and enzyme assisted (EAE) extractions. SFE-CO2 at optimized parameters yielded 11.8 g/100 g of lipophilic fraction, containing 43.3 and 37.4% of α-linolenic and linoleic fatty acids, respectively. The combined PLE with ethanol and water additionally recovered 61.8 g/100 g of polar constituents and reduced the antioxidant capacity of starting material by up to 94%. The major portion of the antioxidants (89-94% in different assays), anthocyanins (231 mg/100 g pomace) and proanthocyanidins (15.9 g/100 g pomace) was present in PLE-EtOH extract. Cyanidin-3-galactoside was the major anthocyanin (146.9 mg/100 g). High-pressure fractionation was more efficient for obtaining bioactive pomace constituents as compared with conventional and enzyme-assisted extractions.


Assuntos
Fracionamento Químico/métodos , Solventes/química , Vaccinium vitis-Idaea , Gerenciamento de Resíduos/métodos , Antocianinas/análise , Antocianinas/química , Antioxidantes/análise , Antioxidantes/química , Dióxido de Carbono/química , Etanol/química , Frutas/química , Galactosídeos/análise , Galactosídeos/química , Química Verde , Resíduos Industriais , Complexos Multienzimáticos/química , Complexos Multienzimáticos/metabolismo , Pressão , Proantocianidinas/análise , Proantocianidinas/química , Água
3.
Food Chem ; 319: 126570, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32172049

RESUMO

A physicochemically stable emulsion was developed by using a novel emulsifier, which was self-assembled colloidal complex of gelatin (GLT) and proanthocyanidins from Chinese bayberry (Myrica rubra Sieb et Zucc.) leaves (BLPs), with epigallocatechin-3-O-gallate (EGCG) as structure units. The GLT-BLP colloidal complexes were spherically shaped by transmission electron microscope (TEM). The data of Fourier transform infrared spectrum (FTIR), circular dichroism (CD), isothermal titration calorimetry (ITC) revealed that the main binding force between GLT and BLPs of the colloidal complexes was hydrogen bond. The incorporation of BLPs to GLT provided GLT with stronger affinity at oil-water interface and thus enhanced the physical stability of GLT-stabilizing emulsion. In addition, the emulsions stabilized by the colloidal complexes showed higher oxidation stability than that stabilized by free GLT only. The novel emulsifier developed in this study have potential applications as functional emulsifiers in food-grade emulsions with high anti-oxidation activity.


Assuntos
Emulsificantes/química , Gelatina/química , Myrica/química , Proantocianidinas/química , Catequina/análogos & derivados , Catequina/química , Emulsificantes/isolamento & purificação , Emulsões/análise , Frutas/química , Folhas de Planta/química
4.
Food Chem ; 316: 126234, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32036176

RESUMO

Plant-based polyphenolics have been reported to bestow health benefits when consumed, which are partially ascribed to their antioxidant activity. Yet, many current in vitro chemical assays to characterize antioxidant potential do not truly reflect the physiological properties of food antioxidants in vivo. The present study employed biological approaches, including a cellular antioxidant activity (CAA) and protein glycation assays, to offer an improved picture of antioxidant potential of phenolic extracts from Georgia peach cultivars. The phenolic extracts from two peach varieties, showing contrasting antioxidant capacities according to hydrophilic-oxygen radical absorbance capacity (H-ORACFL) and ferric reducing antioxidant power (FRAP) assays, exhibited significant differences in two biological tests when the assays were performed on a fresh weight basis. The procyanidins fraction displayed notable antioxidant capacity, when compared to other phenolic classes in the peach extract, in these two biologically relevant assays.


Assuntos
Antioxidantes/química , Prunus persica/química , Antioxidantes/farmacologia , Células CACO-2 , Georgia , Humanos , Fenóis/química , Proantocianidinas/química
5.
J Agric Food Chem ; 68(10): 3163-3170, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32069043

RESUMO

The purpose of this work was to develop a facile strategy based on self-crosslinking between the core and wall materials in the coacervation system for effective procyanidins (PCs) encapsulation. The coacervates were constructed through the interaction of bioactive PCs, gelatin, and sodium alginate, followed by forming cationic bridge of sodium alginate-calcium ions to improve the stability of PCs. When the concentration of PCs and calcium ions were 6.25 and 0.24 mg/mL, respectively, the PC-loaded coacervates showed spherical shape with a size about 150 nm, and the microcapsulation efficiency and yield was 81.19 ± 1.47 and 87.86 ± 2.67%, respectively. The photothermal stability of PCs was effectively improved by embedding them in coacervates. The decrease of mitochondrial membrane potential in PC-12 cells induced by H2O2 was significantly inhibited by PC coacervates, demonstrating an improved protection effect of PCs after being encapsulated in coacervates.


Assuntos
Biflavonoides/química , Quelantes de Cálcio/química , Cálcio/química , Catequina/química , Extratos Vegetais/química , Proantocianidinas/química , Animais , Reagentes para Ligações Cruzadas/química , Estabilidade de Medicamentos , Íons/química , Células PC12 , Ratos , Sementes/química , Vitis
6.
Chem Pharm Bull (Tokyo) ; 68(2): 140-149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32009081

RESUMO

Previously, we reported that the c-Met inhibitory effect of Ephedra Herb extract (EHE) is derived from ingredients besides ephedrine alkaloids. Moreover, analgesic and anti-influenza activities of EHE and ephedrine alkaloids-free Ephedra Herb extract (EFE) have been reported recently. In this study, we examined the fractions containing c-Met kinase inhibitory activity from EHE and the fractions with analgesic and anti-influenza activities from EFE, and elucidated the structural characteristics of the active fractions. Significant c-Met kinase activity was observed in 30, 40, and 50% methanol (MeOH) eluate fractions obtained from water extract of EHE using Diaion HP-20 column chromatography. Similarly, 20 and 40% MeOH, and MeOH eluate fractions obtained from water extract of EFE were found to display analgesic and anti-influenza activities. Reversed phase-HPLC analysis of the active fractions commonly showed broad peaks characteristic of high-molecular mass condensed tannin. The active fractions were analyzed using 13C-NMR and decomposition reactions; the deduced structures of active components were high-molecular mass condensed tannins, which were mainly procyanidin B-type and partly procyanidin A-type, including pyrogallol- and catechol-type flavan 3-ols as extension and terminal units. HPLC and gel permeation chromatography (GPC) analyses estimated that the ratio of pyrogallol- and catechol-type was approximately 9 : 2, and the weight-average molecular weight based on the polystyrene standard was >45000. Furthermore, GPC-based analysis was proposed as the quality evaluation method for high-molecular mass condensed tannin in EHE and EFE.


Assuntos
Ephedra/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Alcaloides/química , Alcaloides/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Animais , Antivirais/química , Antivirais/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , Catequina/química , Catequina/farmacologia , Linhagem Celular Tumoral , Cães , Efedrina/química , Efedrina/farmacologia , Humanos , Células Madin Darby de Rim Canino , Masculino , Camundongos , Proantocianidinas/química , Proantocianidinas/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores
7.
Molecules ; 25(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906397

RESUMO

Chinese bayberry leaf proanthocyanidins (BLPs) are Epigallocatechin gallate (EGCG) oligomers or polymers, which have a lot of health-promoting activity. The activity is closely related to their behavior during in vitro digestion, which remains unknown and hinders further investigations. To clarify the changes of BLPs during gastrointestinal digestion, further research is required. For in vitro digestion, including gastric-intestinal digestion, colon fermentation was applied. Caco-2 monolayer transportation was also applied to investigate the behavior of different BLPs with different degrees of polymerization. The trimers and the tetramers were significantly decreased during in vitro gastric-intestinal digestion resulting in a significant increase in the content of dimers. The dimers and trimers were the main compounds utilized by gut microbiota and they were assumed not to degrade through cleavage of the inflavan bond. The monomers and dimers were able to transport through the Caco-2 monolayer at a rate of 10.45% and 6.4%, respectively.


Assuntos
Biopolímeros/metabolismo , Ácido Gálico/análise , Myrica/química , Proantocianidinas/metabolismo , Disponibilidade Biológica , Biopolímeros/análise , Biopolímeros/química , Células CACO-2 , Catequina/análogos & derivados , Catequina/análise , Catequina/química , Catequina/metabolismo , Digestão , Fermentação , Ácido Gálico/química , Ácido Gálico/metabolismo , Mucosa Gástrica/enzimologia , Microbioma Gastrointestinal , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Intestinos/enzimologia , Folhas de Planta/química , Polimerização , Proantocianidinas/análise , Proantocianidinas/química , Saliva/enzimologia
8.
J Agric Food Chem ; 68(7): 2016-2023, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31986021

RESUMO

The protein precipitation (PP) of bovine serum albumin (BSA), lysozyme (LYS), and alfalfa leaf protein (ALF) by four procyanidin-rich condensed tannin (CT) samples in both 2-[N-morpholino]ethanesulfonic acid (MES) and a modified Goering-Van Soest (GVS) buffer is described. Purified CT samples examined included Vitis vinifera seed (mean degree of polymerization [mDP] 4.1, 16.5% galloylated), Tilia sp. flowers (B-type linkages, mDP 5.9), Vaccinium macrocarpon berries (mDP 8.7, 31.7% A-type linkages). and Trifolium pratense flowers (B-type linkages, mDP 12.3) and were characterized by 2D NMR (>90% purity). In general, CTs precipitated ALF > LYS ≥ BSA. PP in GVS buffer was 1 to 2.25 times greater than that in MES buffer (25 °C). The GVS buffer system better reflects the results/conclusions from the literature on the impacts mDP, galloylation, and A-type linkages have on PP. Determinations of PP using the MES buffer at 37 °C indicated that some of these differences may be attributed to the temperature at which GVS buffer determinations are conducted. In vitro PP studies using the GVS buffer may offer better guidance when selecting CT-containing forages and amendments for ruminant feeding studies.


Assuntos
Biflavonoides/química , Catequina/química , Extratos Vegetais/química , Proteínas de Plantas/química , Proantocianidinas/química , Soroalbumina Bovina/química , Ração Animal/análise , Tampões (Química) , Precipitação Química , Medicago sativa/química , Muramidase/química , Tilia/química , Vaccinium macrocarpon/química , Vitis/química
9.
J Agric Food Chem ; 68(10): 2872-2879, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31244206

RESUMO

Total polyphenol content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), and proanthocyanidin (PAC) content were determined in fruit from three tropical Vaccinium species (Vaccinium consanguineum, Vaccinium floribundum, and Vaccinium poasanum) from Costa Rica sampled at three stages of fruit development. Results show that TAC increased as the fruit developed, while TPC, TFC, and PAC content decreased. Anthocyanin profiles were evaluated using electrospray ionization tandem mass spectrometry. Cyanidin and delphinidin glycosides were the predominant anthocyanins for the three tropical Vaccinium species. Proanthocyanidins were characterized using attenuated total reflection Fourier transform infrared spectroscopy, nuclear magnetic resonance, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The presence of procyanidin structures with B-type interflavan bonds were observed, but deconvolution of mass spectrometry isotope patterns indicated that PACs with one or more A-type interflavan bonds accounted for more than 74% of the oligomers at each degree of polymerization.


Assuntos
Antocianinas/química , Extratos Vegetais/química , Proantocianidinas/química , Vaccinium/química , Costa Rica , Frutas/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Vaccinium/classificação
10.
J Agric Food Chem ; 68(10): 2917-2926, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31013083

RESUMO

An improved analytical depolymerization method for characterizing condensed tannins was developed with menthofuran (3,6-dimethyl-4,5,6,7-tetrahydro-1-benzofuran) as the nucleophilic trapping reagent. Herein, menthofuran was compared with routinely used nucleophiles, phloroglucinol and 2-mercaptoethanol. At 30 °C and in the presence of 0.1 M HCl, menthofuran displayed the outstanding ability to enable the fast and full depolymerization of procyanidin B2 using only a 1:1 molar ratio of both reactants. Under the same conditions, phloroglucinol and 2-mercaptoethanol led to a reaction equilibrium with significantly lower conversion yields. Application to commercial tannin extracts showed that a menthofuran-to-extract weight ratio of 1 gave the same yields of procyanidin constitutive units as 10-fold higher molecular equivalent phloroglucinol and 100-fold 2-mercaptoethanol. Finally, guidelines for implementing the menthofuran depolymerization method are proposed to assess the tannin content and composition of extracts as well as of plant materials without prior extraction.


Assuntos
Técnicas de Química Analítica/métodos , Extratos Vegetais/química , Taninos/química , Biflavonoides/química , Catequina/química , Monoterpenos/química , Polimerização , Proantocianidinas/química
11.
J Agric Food Chem ; 68(10): 2891-2899, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31180670

RESUMO

The kinetics and quantitative and qualitative effects of grape proanthocyanidin (PA) adsorption to grape skin-derived cell wall material (CWM) were investigated in five different temperature-ethanol conditions. Progress curves for each condition were constructed by monitoring the decrease in concentration of PA solutions after exposure to CWM over 720 min. Adsorption isotherms were constructed for each condition, and a Langmuir equation model was applied to each via regression analysis. Compositional changes in the PA solutions after exposure to CWM were determined using phloroglucinolysis and gel permeation chromatography (GPC). A negative correlation between PA adsorption and both the temperature and ethanol concentration was found. Progress curves suggested that both the temperature and ethanol affect the equilibration rate of the adsorption reactions. Additionally, equilibration rates for lower temperature and ethanol concentration conditions were found to be much longer than previously reported, taking up to 720 min. Phloroglucinolysis results showed no discernible correlation between the temperature or ethanol concentration and percent galloylation or percent gallo units of adsorbed compounds. Analyses by phloroglucinolysis and GPC indicate a preferential adsorption of larger molecular weight PAs under all conditions, although no discernible impact on PA composition was detected. Additionally, findings suggest that both the temperature and ethanol concentration impact the percent reduction in molar mass of the PA solution. Data from this study were ultimately utilized to develop a computational model for predicting phenolic extraction during red wine fermentations.


Assuntos
Etanol/química , Proantocianidinas/química , Vinho/análise , Adsorção , Parede Celular/química , Frutas/química , Cinética , Fenóis/química , Temperatura , Vitis/química
12.
J Sci Food Agric ; 100(3): 1213-1219, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31680253

RESUMO

BACKGROUND: In this article the relationship between lipophilic grape seed proanthocyanidin (LGSP) and acrylamide formation in potato-based products was investigated. The acrylamide, reducing sugar, asparagine, and 3-aminopropionamide contents were determined by high-performance liquid chromatography mass spectrometry (HPLC-MS). Sensory evaluation was used to evaluate the quality of the products. RESULTS: The results showed that LGSP presented greater inhibition effect on the acrylamide formation than the commonly used commercial antioxidants. Furthermore, 81.5% and 84.7% of acrylamide was reduced in potato crisps and French fries after adding 0.1% and 0.05% LGSP (w/w) in palm oil, respectively. When the concentrations of LGSP were less than 0.1%, there was no significant difference between LGSP-treated samples and control sample for sensory evaluation. CONCLUSION: Thus, LGSP is effective in reducing the level of acrylamide and maintaining the reasonable sensory attributes of potato fried foods. The results indicate that LGSP may be used as a potential additive for reducing acrylamide formation in fried foods. © 2019 Society of Chemical Industry.


Assuntos
Acrilamida/química , Aditivos Alimentares/química , Extrato de Sementes de Uva/química , Proantocianidinas/química , Culinária , Temperatura Alta , Humanos , Oxirredução , Lanches , Solanum tuberosum/química , Paladar
13.
J Ethnopharmacol ; 247: 112253, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31562952

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The medicinal properties of grapes (Vitis vinifera L.) are well known since ancient times. Ethnobotanical grape preparations, like the Ayurvedic Darakchasava are used as cardiotonic and for the treatment of cardiovascular diseases. Dried grape products are also applied in Iranian traditional medicine for memory problems, which are linked to the pathology of brain microvessels, a special part of the cardiovascular system. The anti-inflammatory and protective effects of these traditional preparations on the cardiovascular system are related to their bioactive phenolic compounds. AIM OF THE STUDY: The blood-brain barrier (BBB), formed by brain capillaries, is not only involved in inflammatory and other diseases of the central nervous system, but also in many systemic diseases with an inflammatory component. Dietary obesity is a systemic chronic inflammatory condition in which the peripheral and central vascular system is affected. Among the cerebrovascular changes in obesity defective leptin transport across the BBB related to central leptin resistance is observed. Our aim was to study the protective effects of grape phenolic compounds epicatechin (EC), gallic acid (GA) and resveratrol (RSV) and grape-seed proanthocyanidin-rich extract (GSPE) on a cytokine-induced vascular endothelial inflammation model. Using a culture model of the BBB we investigated cytokine-induced endothelial damage and changes in the expression of leptin receptors and leptin transfer. MATERIALS AND METHODS: For the BBB model, primary cultures of rat brain endothelial cells, glial cells and pericytes were used in co-culture. Cells were treated by tumor necrosis factor-α (TNF-α) and interleukin-1 ß (IL-1ß) (10 ng/ml each) to induce damage. Cell toxicity was evaluated by the measurement of impedance. The expression of leptin receptors was assessed by RT-qPCR and western blot. The production of reactive oxygen species (ROS) and nitric oxide (NO) were detected by fluorescent probes. RESULTS: GSPE (10 µg/ml), EC (10 µM), GA (1 µM) or RSV (10 µM) did not change the viability of brain endothelial cells. The gene expression of the short leptin receptor isoform, Ob-Ra, was up-regulated by GSPE, EC and RSV, while the mRNA levels of Lrp2 and clusterin, clu/ApoJ were not affected. The tested compounds did not change the expression of the long leptin receptor isoform, Ob-Rb. RSV protected against the cytokine-induced increase in albumin permeability of the BBB model. GSPE and EC exerted an antioxidant effect and GSPE increased NO both alone and in the presence of cytokines. The cytokine-induced nuclear translocation of transcription factor NF-κB was blocked by GSPE, GA and RSV. Cytokines increased the mRNA expression of Lrp2 which was inhibited by EC. RSV increased Ob-Ra and Clu in the presence of cytokines. Cytokines elevated leptin transfer across the BBB model, which was not modified by GSPE or RSV. CONCLUSION: Our results obtained on cell culture models confirm that natural grape compounds protect vascular endothelial cells against inflammatory damage in accordance with the ethnopharmacological use of grape preparations in cardiovascular diseases. Furthermore, grape compounds and GSPE, by exerting a beneficial effect on the BBB, may also be considered in the treatment of obesity after validation in clinical trials.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Inflamação/tratamento farmacológico , Proantocianidinas/farmacologia , Vitis/química , Animais , Animais Recém-Nascidos , Astrócitos , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/imunologia , Catequina/farmacologia , Células Cultivadas , Citocinas/imunologia , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/imunologia , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Etnofarmacologia , Ácido Gálico/farmacologia , Extrato de Sementes de Uva/química , Extrato de Sementes de Uva/uso terapêutico , Humanos , Inflamação/imunologia , Inflamação/patologia , Leptina/imunologia , Leptina/metabolismo , Medicina Ayurvédica/métodos , Cultura Primária de Células , Proantocianidinas/química , Proantocianidinas/uso terapêutico , Ratos , Espécies Reativas de Oxigênio/metabolismo , Receptores para Leptina/metabolismo , Resveratrol/farmacologia
14.
Food Chem ; 309: 125636, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31711810

RESUMO

Physico-chemical instability is a damaging defect that can occur in clear bottled beverages leading to the formation of haze. In a previous study, we showed the presence of proteins in haze gathered from apple juices. For the first time, proteomics was used to sequence and identify four pathogenesis-related proteins (PRPs) from the haze of a commercial apple juice. Then, a study involving purified PRPs and polyphenols from apple juice was conducted in model solution to understand the mechanisms by which they are involved in haze formation. Visual assessment revealed that apple juice pathogenesis-related proteins are able to form haze alone when thermally denatured. These proteins were also able to interact with apple juice procyanidins to form complexes that can be precipitated using ultracentrifugation, even without prior heating. These interactions were greater when the degree of polymerization of tannins increased.


Assuntos
Sucos de Frutas e Vegetais/análise , Malus/química , Proteínas de Plantas/química , Polifenóis/química , Cromatografia Líquida de Alta Pressão , Temperatura Alta , Malus/metabolismo , Peptídeos/análise , Proteínas de Plantas/metabolismo , Polimerização , Proantocianidinas/química , Espectrometria de Massas em Tandem , Taninos/química
15.
Mater Sci Eng C Mater Biol Appl ; 106: 110056, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753372

RESUMO

Proanthocyanidins (PCs), a component of grape seed extract (GSE), have recently being used for the treatment of wounds. However, poor absorption, poor stability and rapid elimination from the systemic circulation limit its acceptance. In addressing these problems, we herein report the development of PCs based nanoformulations (PCs/SOLU) for the first time based on 1% GSE and assessed its wound healing potential in-vivo on the wistar rats. GSE and PCs/SOLU nanodispersions 1% were prepared by incorporating them into the ointment base via uniform mixing to form ointment which could be easily applied topically to wounds. The antibacterial activity of PCs/SOLU against gram positive and gram-negative bacteria strains proved that the cell membranes became more permeable with disrupted cell structure. While carrageenan and histamine induced rat paw edema analyses show there was no inflammatory signs in animals treated with 1 wt% of PCs/SOLU nanodispersion. Excision wound measuring about 3 cm in depth was created on the wistar rats. The ointment was applied topically on the wounded site and the wound contraction was measured daily. Grape seed extract (GSE) ointment, ointment base and povidone­iodine (Povi-Iod) ointment of about 1% was used as the control, positive and negative standards. PCs/SOLU nanodispersion heals the wound by mobilising the fibroblasts in the wound site and inhibits the inflammatory response through decreased expression of monocyte. The macroscopical, immunological and histopathological assessments revealed that PCs/SOLU nanodispersion ointment usage improves the cell adhesion and proliferation.


Assuntos
Nanoestruturas/química , Pomadas/farmacologia , Proantocianidinas/química , Cicatrização/efeitos dos fármacos , Administração Tópica , Animais , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/patologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Extrato de Sementes de Uva/química , Hemólise/efeitos dos fármacos , Humanos , Masculino , Pomadas/química , Pomadas/uso terapêutico , Polietilenoglicóis/química , Polivinil/química , Proantocianidinas/farmacologia , Proantocianidinas/uso terapêutico , Ratos , Ratos Wistar , Pele/patologia
16.
Molecules ; 24(24)2019 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-31817948

RESUMO

Yeast are able to modulate many sensory parameters of wines during red must fermentation. The effect on color and on the formation of derived pigments during fermentation has been studied thoroughly since the 90s. Yeast can increase grape anthocyanin's color by acidification by hyperchromic effect (increase of flavylium molecules). Recent studies with non-Saccharomyces species, as Lachancea thermotolerans, described the intense effect of some strains on anthocyanin's color, and subsequent, stability, by strongly reducing wine's pH during fermentation. Moreover, selected yeast strains of Saccharomyces have been shown to release metabolites such as pyruvic acid or acetaldehyde that promote the formation of vitisin A and B pyranoanthocyanins during must fermentation. Schizosaccharomyces pombe, because of its specific metabolism, can produce higher concentrations of pyruvate, which enhances the formation of vitisin A-type derivatives. The hydroxycinnamate decarboxylase activity that some Saccharomyces strains express during fermentation also promotes the formation of vinylphenolic derivatives. Some non-Saccharomyces species, such as S. pombe or P. guilliermondii can also improve the production of these derivatives compared to selected strains of Saccharomyces cerevisiae. Lastly, some yeasts are also able to modulate the formations of polymeric pigments between grape anthocyanins and flavonoids, such as catechins and procyanidins.


Assuntos
Antocianinas/química , Proantocianidinas/farmacologia , Vitis/química , Antocianinas/farmacologia , Benzofuranos/química , Fermentação/efeitos dos fármacos , Fenóis/química , Pigmentação/efeitos dos fármacos , Proantocianidinas/química , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomycetales/efeitos dos fármacos , Vinho/análise
17.
Artif Cells Nanomed Biotechnol ; 47(1): 4293-4304, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810396

RESUMO

Instability of silk fibroin nanoparticles (SFNPs) in physiologic condition hinders its application as drug delivery vehicle. Herein, indocyanine green (ICG) loaded silk fibroin nanoparticles (ICG-SFNPs) was firstly prepared and then crosslinked by proanthocyanidins to obtain the stable ICG-CSFNPs for killing the residual tumour niche under near infra-red irradiation (NIR) after surgery. The particle size and zeta potentials of ICG-CSFNPs was 120.1 nm and -40.4 mV, respectively. Moreover, ICG-CSFNPs exhibited good stability of particle size in the physiological medium. Meanwhile, the stable photothermal properties of ICG-CSFNPs were not compromised even after several cycles of NIR. Few of the ICG-CSFNPs were phagocytized by RAW264.7 macrophage in vitro, while they were easily internalized by C6 glioma cells, resulting in their significant toxicity on tumour cells after NIR. The pharmacokinetic study showed that ICG-CSFNPs had a longer blood circulation time than ICG-SFNPs, making them more distribution in glioma after intravenous administration in vivo. Meanwhile, the pharmacological study showed the more effective inhibition of tumour growth was exhibited by ICG-CSFNPs in C6 glioma-bearing mice after NIR. Overall, the cross-linked nanoparticles of silk fibroin may be a promising vehicle of ICG for photothermal therapy of glioma after surgical resection.


Assuntos
Fibroínas/química , Glioma/terapia , Verde de Indocianina/química , Verde de Indocianina/uso terapêutico , Nanopartículas/química , Fototerapia , Proantocianidinas/química , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Glioma/diagnóstico por imagem , Glioma/patologia , Verde de Indocianina/farmacocinética , Raios Infravermelhos/uso terapêutico , Masculino , Camundongos , Imagem Óptica , Ratos , Distribuição Tecidual
18.
Molecules ; 24(21)2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694314

RESUMO

Lotus seed epicarp, the main by-product of lotus seed processing, is abundant in polyphenols. In this study, polyphenols in lotus seed epicarp were separated by Sephadex LH-20 gel filtration chromatography to yield Fraction-I (F-I), Fraction-II (F-II), and Fraction-III (F-III). The polyphenol compounds in the three fractions were identified by UPLC-MI-TOF-MS. Six kinds of polyphenol compounds including cyanidin-3-O-glucoside, procyanidin trimer, and phlorizin were identified in F-I, and prodelphinidin dimer B, procyanidin dimer, and quercetin hexoside isomer were found in F-II. However, there was only procyanidin dimer identified in F-III. The in vitro antioxidant activities of the three fractions were also investigated. We found F-I, F-II, and F-III had strong potential antioxidant activities in the order of F-III > F-II > F-I. Our results suggested that polyphenols from lotus seed epicarp might be suitable for use as a potential food additive.


Assuntos
Antioxidantes/química , Lotus/química , Polifenóis/química , Sementes/química , Antocianinas/química , Biflavonoides/química , Catequina/química , Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos/química , Extratos Vegetais/química , Proantocianidinas/química
19.
J Agric Food Chem ; 67(51): 14066-14073, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31762280

RESUMO

In the present study, the inhibitory effect of condensed tannins (CTs) on cholesterol esterase (CEase) was studied. The underlying mechanisms were evaluated by reaction kinetics, turbidity and particle size analyses, multispectroscopy methods, thermodynamics, and computer molecular simulations. CTs showed potent CEase inhibitory activity with an IC50 value of 64.19 µg/mL, and the CEase activity decreased with increasing CT content in a mixed-competitive manner, which was verified by molecular docking simulations. Fluorescence and UV-vis measurements revealed that complexes were formed from CEase and CTs by noncovalent interaction. Isothermal titration calorimetry indicated that the interaction between CEase and CTs occurred through hydrogen bonding and hydrophobic interactions. Circular dichroism analysis suggested that CTs inhibited the activity of CEase by altering the secondary structure of CEase. The inhibition of CTs on CEase in the gastrointestinal tract might be one mechanism for its cholesterol-lowering effect.


Assuntos
Inibidores Enzimáticos/química , Musa/química , Extratos Vegetais/química , Proantocianidinas/química , Esterol Esterase/antagonistas & inibidores , Resíduos/análise , Dicroísmo Circular , Frutas/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Esterol Esterase/química
20.
J Agric Food Chem ; 67(48): 13318-13326, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31604012

RESUMO

For some complex mixtures, chromatographic techniques are insufficient to separate the large numbers of compounds present. In addition, these mixtures often contain compounds with similar or identical molecular masses and shared fragmentation transitions. Advancements in mass spectrometry have provided more and more detailed molecular profiles with significant increases in resolution. This has led to a capacity to distinguish a very large number of compounds in complex mixtures, providing overwhelming data sets. The approach of calculating molecular formulas from a mass list has become more and more problematic as the number of signals has increased exponentially, to the point that it has become impossible to manually interpret the thousands of mass signals. The current approach is to calculate a list of possible formulas that fall within a specific mass error of the observed signal. Then, one must look for possible structures that can be derived from each entry on the list of formulas. However, an alternative approach is to anticipate the possible structures of a particular set of compounds, such as red wine pigments, and then compare the ion signals against a predicted list. To that end, starting with known wine pigment types, we have generated a set of expected wine pigment variants based on known derivatives of condensed tannin oligomers, anthocyanins, and fermentation products. After the ability to distinguish compounds by mass spectrometry was accounted for, over 1 million results were generated consisting of known and anticipated wine pigments. A comparison with a small sample of wine phenolic fractions show a large number of matches, suggesting that this approach may be helpful.


Assuntos
Misturas Complexas/química , Vinho/análise , Antocianinas/química , Espectrometria de Massas , Fenóis/análise , Fenóis/química , Proantocianidinas/química
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