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1.
Mar Drugs ; 21(3)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36976198

RESUMO

Excisional wounds are considered one of the most common physical injuries. This study aims to test the effect of a nanophytosomal formulation loaded with a dried hydroalcoholic extract of S. platensis on promoting excisional wound healing. The Spirulina platensis nanophytosomal formulation (SPNP) containing 100 mg PC and 50 mg CH exhibited optimum physicochemical characteristics regarding particle size (598.40 ± 9.68 nm), zeta potential (-19.8 ± 0.49 mV), entrapment efficiency (62.76 ± 1.75%), and Q6h (74.00 ± 1.90%). It was selected to prepare an HPMC gel (SPNP-gel). Through metabolomic profiling of the algal extract, thirteen compounds were identified. Molecular docking of the identified compounds on the active site of the HMGB-1 protein revealed that 12,13-DiHome had the highest docking score of -7.130 kcal/mol. SPNP-gel showed higher wound closure potential and enhanced histopathological alterations as compared to standard (MEBO® ointment) and S. platensis gel in wounded Sprague-Dawley rats. Collectively, NPS promoted the wound healing process by enhancing the autophagy process (LC3B/Beclin-1) and the NRF-2/HO-1antioxidant pathway and halting the inflammatory (TNF-, NF-κB, TlR-4 and VEGF), apoptotic processes (AIF, Caspase-3), and the downregulation of HGMB-1 protein expression. The present study's findings suggest that the topical application of SPNP-gel possesses a potential therapeutic effect in excisional wound healing, chiefly by downregulating HGMB-1 protein expression.


Assuntos
Proteínas HMGB , Cicatrização , Ratos , Animais , Ratos Sprague-Dawley , Simulação de Acoplamento Molecular , Proteínas HMGB/farmacologia
2.
J Sci Food Agric ; 103(5): 2295-2303, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36636878

RESUMO

BACKGROUND: The accurate characterization of grapevine cultivars (Vitis vinifera) is crucial for grape growers, winemakers, wine sellers, consumers and authorities, considering that mistakes could involve significant damage to the wine economic system. To avoid any misunderstanding, morphological, molecular and chemical tools are developed to positively identify grape varieties. RESULTS: E-ε-viniferin is a stilbene dimer mainly present in the woody part of grapevine and present as a mixture of two enantiomers: (7aR, 8aR)-(-)-E-ε-viniferin (1) and (7aS, 8aS)-(+)-E-ε-viniferin (2). In addition to phenotypic and genotypic approaches, a chemotaxonomic method using E-ε-viniferin enantiomers as chemical markers of grapevine cultivars was investigated. The isolation and purification of E-ε-viniferin enantiomers by preparative high-performance liquid chromatography (HPLC) and chiral HPLC from 14 red and eight white grapevine cane cultivars enabled us to determine the proportion of each enantiomer and therefore to calculate the enantiomeric excess for each variety. The relative abundance of each E-ε-viniferin enantiomer permitted us to distinguish grape varieties, as well as to establish cultivar relationships and patterns through statistical analysis. CONCLUSION: This pioneering work highlighting the enantiomeric excess of E-ε-viniferin as a chemical marker of grapevine paves the way for further studies to understand what mechanisms are involved in the production of these enantiomers in grapevine. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Benzofuranos , Estilbenos , Vitis , Vinho , Estilbenos/análise , Vitis/química , Vinho/análise , Benzofuranos/análise
3.
Compr Rev Food Sci Food Saf ; 21(2): 1161-1197, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35092346

RESUMO

Mycotoxins are metabolites produced by molds that contaminate food commodities, are harmful to both humans and animals, as well as cause economic losses. Many countries have set regulatory limits and strict thresholds to control the level of mycotoxins in food and feedstuffs. New technologies and strategies have been developed to inhibit toxigenic fungal invasion and to decontaminate mycotoxins. However, many of these strategies do not sufficiently detoxify mycotoxins and leave residual toxic by-products. This review focuses on the use of phenolic compounds obtained from botanical extracts as promising bioagents to inhibit fungal growth and/or to limit mycotoxin yields. The mechanism of these botanicals, legislation concerning their use, and their safety are also discussed. In addition, recent strategies to overcome stability and solubility constraints of phenolic compounds to be used in food and feed stuffs are also mentioned.


Assuntos
Contaminação de Alimentos , Micotoxinas , Animais , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Fungos , Micotoxinas/análise
4.
Molecules ; 26(2)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466739

RESUMO

Fusarium graminearum is a fungal pathogen that can colonize small-grain cereals and maize and secrete type B trichothecene (TCTB) mycotoxins. The development of environmental-friendly strategies guaranteeing the safety of food and feed is a key challenge facing agriculture today. One of these strategies lies on the promising capacity of products issued from natural sources to counteract crop pests. In this work, the in vitro efficiency of sixteen extracts obtained from eight natural sources using subcritical water extraction at two temperatures was assessed against fungal growth and TCTB production by F. graminearum. Maritime pine sawdust extract was shown to be extremely efficient, leading to a significant inhibition of up to 89% of the fungal growth and up to 65% reduction of the mycotoxin production by F. graminearum. Liquid chromatography/mass spectrometry analysis of this active extract revealed the presence of three families of phenolics with a predominance of methylated compounds and suggested that the abundance of methylated structures, and therefore of hydrophobic compounds, could be a primary factor underpinning the activity of the maritime pine sawdust extract. Altogether, our data support that wood/forest by-products could be promising sources of bioactive compounds for controlling F. graminearum and its production of mycotoxins.


Assuntos
Florestas , Fusarium/metabolismo , Micotoxinas/biossíntese , Preparações Farmacêuticas/administração & dosagem , Extratos Vegetais/farmacologia , Vinho/análise , Madeira/química , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Preparações Farmacêuticas/metabolismo , Vitis/química
5.
J Nat Prod ; 83(5): 1611-1622, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32343138

RESUMO

Six new triterpenoids (1-6), two known genins (7 and 8), and five known functionalized triterpenoids (9-13) were isolated from a Quercus robur heartwood extract. The purification protocol was guided by LC-HRMS by searching for structural analogues of bartogenic acid on the basis of their putative empirical formula. The structures of the new compounds were unequivocally elucidated using HRESIMS and 1D/2D NMR experiments. Sensory analyses were performed in water and in a non-oaked white wine on the pure compounds 1-13 at 5 mg/L. All molecules were perceived as bitter in water and wine, but they were mostly reported as modifying the wine taste balance. Using LC-HRMS, compounds 1-13 were observed in oaked red wine and cognac and were semiquantified in oak wood extracts. The influence of two cooperage parameters, oak species and toasting process, on compounds 1-13 content was studied. All compounds were found in quantities significantly higher in pedunculate than in sessile oak wood. Toasting is a key step in barrel manufacture and modulates the concentration of the discussed compounds. Significantly higher quantities were observed in untoasted wood compared to medium or highly toasted wood. These findings provide new insights into the molecular origin of taste changes due to oak aging.


Assuntos
Quercus/química , Triterpenos/química , Vinho/análise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Paladar , Madeira/química
6.
Bioorg Chem ; 102: 104093, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717693

RESUMO

Previously phytochemical investigations carried out on the flowers and trunk bark extracts of Citharexylum spinosum L. tree, allowed the isolation of twenty molecules belonging to several families of natural substances [triterpene acids, iridoid glycosides, phenylethanoid glycosides, 8,3'-neolignan glycosides, together with other phenolic compounds]. In the present work, a biological evaluation (anti-tyrosinase, anticholinesterase and cytotoxic activities) was performed on the prepared extracts and the isolated secondary metabolites. The results showed that the EtOAc extract of the trunk bark displayed the highest anti-tyrosinase effect with a percent inhibition of 55.0 ± 1.8% at a concentration of 100 µg/mL. The highest anticholinesterase activity was presented by the same extract with an IC50 value of 99.97 ± 3.01 µg/mL. The EtOAc extract of flowers and that of the trunk bark displayed the best cytotoxic property with IC50 values of 96.00 ± 2.85 and 88.75 ± 2.00 µg/mL, respectively, against the human cervical cancer cell line (HeLa), and IC50 values of 188.23 ± 3.88 and 197.00 ± 4.25 µg/mL, respectively, against the human lung cancer (A549) cell lines. Biological investigation of the pure compounds showed that the two 8,3'-neolignan glycosides, plucheosides D1-D2, generate the highest anti-tyrosinase potency with a percent inhibition of 61.4 ± 2.0 and 79.5 ± 2.3%, respectively, at a concentration of 100 µM. The iridoid glycosides exhibited a significant anticholinesterase activity with IC50 values ranging from 17.19 ± 1.02 to 52.24 ± 2.50 µM. Triterpene pentacyclic acids and iridoid glycosides exerted encouraging cytotoxic effects against HeLa with IC50 values ranging from 9.00 ± 1.10 to 25.00 ± 1.00 µM. The study of the structure-activity relationship (SAR) has been sufficiently and widely discussed. The natural compounds that exhibited the significant bioactivities were docked.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Verbenaceae/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Colinesterases/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Camundongos , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade
7.
J Sep Sci ; 43(6): 1080-1088, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31970869

RESUMO

Pine knots are a rich source of lignans, flavonoids, and stilbenes. These bioactive compounds are widely known for their roles to combat human disorders but also to protect plants against pathogens. In order to gain knowledge inside their potential activities, a suitable isolation and purification of these high-added value compounds is required. To this end, centrifugal partition chromatography, as a rapid and useful methodology of separation, was employed and developed. The coefficient partition values (KD ) of six major compounds in nine biphasic solvent systems were determined to evaluate the most appropriate system. Two-step centrifugal partition chromatography was required to separate lignans using ARIZONA system K (n-heptane/ethyl acetate/methanol/water 1:2:1:2, v:v) and to isolate stilbenes and flavonoids using ARIZONA system P (n-heptane/ethyl acetate/methanol/water 6:5:6:5, v:v). Eight one-compound enriched-fractions were obtained as follows: nortrachelogenin (70.1%), secoisolariciresinol (53.7%), isolariciresinol (61.1%), taxifolin (48.4%), pinocembrin (91.3%), pinobanksin (91.1%), pinosylvin (91.4%), and pinosylvin monomethyl ether (91.1%). Additionally, the centrifugal partition chromatography allowed to unravel the composition of pine knot owing to the several fractions generated. Twenty-two compounds were characterized by liquid chromatography-mass spectrometry and NMR spectroscopy, some of which are described for the first time in literature.


Assuntos
Centrifugação , Pinus/química , Polifenóis/isolamento & purificação , Cromatografia Líquida , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Polifenóis/química
8.
J Nat Prod ; 82(2): 265-275, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30689385

RESUMO

Eight new triterpenoids (1-8), the known genin (9), and two known functionalized triterpenoids (10 and 11) were isolated from a Quercus petraea heartwood extract. The structures of the new compounds were unequivocally elucidated using HRESIMS and 1D/2D NMR experiments. Sensory analyses were performed in a non-oaked wine on the pure compounds 1-11. Except compounds 1 and 11, all molecules exhibited a sweet taste at 5 mg/L that was particularly intense for compounds 3 and 9. Using LC-HRMS, compounds 1-11 were observed in an oak wood extract and in oaked red wine and cognac. They were also semiquantified in several samples of sessile ( Q. petraea) and pedunculate ( Q. robur) oak wood extract. All compounds were found in quantities significantly higher in sessile than in pedunculate oak wood. These results support the hypothesis of their contribution to the increase in sweetness during oak aging and show that they can be used as chemical markers to identify the species of oak used for cooperage.


Assuntos
Quercus/química , Triterpenos/isolamento & purificação , Vinho/análise , Espectroscopia de Ressonância Magnética , Extratos Vegetais/análise , Paladar , Triterpenos/análise , Triterpenos/química , Madeira/química
9.
Phytochem Anal ; 30(3): 320-331, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30644147

RESUMO

INTRODUCTION: Grapevine wood and roots are by-products obtained during vineyard management. This plentiful biomass is known to be rich in stilbenes and can be used as a source of high-value compounds as well as active natural extracts. However, the stilbenes in grapevine wood and roots from different cultivars and rootstocks remain to be characterized. OBJECTIVE: The present study investigated the stilbene content of eight major Vitis vinifera cultivars and six different rootstocks. In addition, the distribution of stilbenes was established for each of seven parts into which the plants were sub-divided. METHODOLOGY: For stilbene characterization and quantification purposes, an ultra-high performance liquid chromatography-diode array detector-mass spectrometry (UHPLC-DAD-MS/MS) analysis of different samples was carried out. Moreover, structural data of stilbenes was unambiguously studied by nuclear magnetic resonance (NMR) spectra. RESULTS: Whatever the cultivar/rootstock combination, stilbenes were found to be oligomerized from the aerial part to the root system. Furthermore, stilbene content varied widely depending on the cultivars and rootstocks. For instance, the cultivars Merlot, Tannat and Gamay noir were the richest in stilbenes while the rootstocks Gravesac, Fercal and 3390C contained the highest amounts. CONCLUSION: These findings provide insight into the knowledge that major grapevine cultivars and rootstocks can be used as a potential source of complex stilbenes.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Raízes de Plantas/química , Espectroscopia de Prótons por Ressonância Magnética/métodos , Estilbenos/análise , Espectrometria de Massas em Tandem/métodos , Vitis/química , Madeira , Extratos Vegetais/análise , Extratos Vegetais/química , Polimerização
10.
Anal Chem ; 88(20): 9941-9948, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27602433

RESUMO

Centrifugal partition chromatography (CPC) and all countercurrent separation apparatus provide chemists with efficient ways to work with complex matrixes, especially in the domain of natural products. However, despite the great advances provided by these techniques, more efficient ways of analyzing the output flow would bring further enhancement. This study describe a hyphenated approach made by coupling NMR with CPC through a hybrid-indirect coupling made possible by using a solid phase extraction (SPE) apparatus intended for high-pressure liquid chromatography (HPLC)-NMR hyphenation. Some hardware changes were needed to adapt the incompatible flow-rates and a reverse-engineering approach that led to the specific software required to control the apparatus. 1D 1HNMR and 1H-1H correlation spectroscopy (COSY) spectra were acquired in reasonable time without the need for any solvent-suppression method thanks to the SPE nitrogen drying step. The reduced usage of expensive deuterated solvents from several hundreds of milliliters to the milliliter order is the major improvement of this approach compared to the previously published ones.

11.
J Nat Prod ; 79(10): 2432-2438, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27684096

RESUMO

Quercoresinosides A and B (1 and 2), two new lignans, were isolated from a toasted Quercus petraea heartwood extract along with a known compound, 3-methoxy-4-hydroxyphenol 1-O-ß-d-(6'-O-galloyl)glucopyranoside (3). The purification protocol was based on a taste-guided approach that sought to reveal new bitter compounds released from oak wood into wines and spirits. HRMS and NMR data were used to establish that compounds 1 and 2 are lignan derivatives bearing a glucosyl unit and a galloyl unit at the same positions. Hydrolysis of these compounds showed that they could be distinguished by the absolute configuration of their respective lyoniresinol genin as determined by chiral LC-HRMS in comparison with (+)- and (-)-lyoniresinol standards. Sensory analyses were performed in a non-oaked wine on the pure compounds 1-3. The three molecules exhibited a bitter taste at 2 mg/L that was particularly intense for compounds 2 and 3. Finally, LC-HRMS demonstrated the occurrence of compounds 1-3 in oaked wine and brandy, which supports the hypothesis of their contributions to the increase in bitterness during oak aging.


Assuntos
Lignanas/isolamento & purificação , Quercus/química , Vinho , Anisóis , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Lignanas/química , Estrutura Molecular , Naftalenos , Ressonância Magnética Nuclear Biomolecular , Paladar , Madeira/química
12.
Bioorg Med Chem Lett ; 25(18): 3825-30, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26248805

RESUMO

A phytochemical investigation of the roots of Ononis angustissima L. (Fabaceae) offered to the bio-guided isolation of new isoflavone 3-(4-(glucopyranosyloxy)-5-hydroxy-2-methoxyphenyl)-7-hydroxy-4H-chromen-4-one 1, together with nine known compounds, ononin 2, formononetin 3, (+)-puerol A-2'-O-ß-D-glucose 4, (-)-puerol B-2'-O-ß-D-glucopyranose ((-)-sophoraside A) 5, (+)-puerol A 6, (-)-trifolirhizin 7, (-)-trifolirhizin-6'-O-malonate 8, (-)-maackiain 9 and (-)-medicarpin 10. Compounds 2-10 were isolated and identified for the first time in Ononis angustissima. We investigated antioxidant capacities of isolated molecules and results showed that compound 6 exhibited the highest antioxidant activity with IC50 values of 19.53 µg/mL, 28.29 µg/mL and 38.53 µg/mL by DPPH radical, ABTS radical cation and reducing power assay, respectively, and an interesting IC50 (20.45 µg/mL) of 1 against DPPH. In addition, the neuroprotective activity of six isolated molecules (4-7, 9, 10) were evaluated. Following the exposure of PC12 cells to Aß25-35, compounds 9 and 10 triggered a significant increase of cell viability and in a dose dependent manner.


Assuntos
Antioxidantes/farmacologia , Ononis/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Radicais Livres/antagonistas & inibidores , Estrutura Molecular , Células PC12 , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ratos , Relação Estrutura-Atividade , Ácidos Sulfônicos/antagonistas & inibidores , Tunísia
13.
Biochim Biophys Acta ; 1830(11): 5068-74, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23830862

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder. There is a consensus that Aß is a pathologic agent and that its toxic effects, which are at present incompletely understood, may occur through several potential mechanisms. Polyphenols are known to have wide-ranging properties with regard to health and for helping to prevent various diseases like neurodegenerative disorders. Thus inhibiting the formation of toxic Aß assemblies is a reasonable hypothesis to prevent and perhaps treat AD METHODS: Solution NMR and molecular modeling were used to obtain more information about the interaction between the Aß1-40 and the polyphenol ε-viniferin glucoside (EVG) and particularly the Aß residues involved in the complex. RESULTS: The study demonstrates the formation of a complex between two EVG molecules and Aß1-40 in peptide characteristic regions that could be in agreement with the inhibition of aggregation. Indeed, in previous studies, we reported that EVG strongly inhibited in vitro the fibril formation of the full length peptides Aß1-40 and Aß1-42, and had a strong protective effect against PC12 cell death induced by these peptides. CONCLUSION: For the full length peptide Aß1-40, the binding sites observed could explain the EVG inhibitory effect on fibrillization and thus prevent amyloidogenic neurotoxicity. GENERAL SIGNIFICANCE: Even though this interaction might be important at the biological level to explain the protective effect of polyphenols in neurodegenerative diseases, caution is required when extrapolating this in vitro model to human physiology.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Benzofuranos/química , Glucosídeos/química , Fragmentos de Peptídeos/química , Polifenóis/química , Estilbenos/química , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Benzofuranos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Glucosídeos/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Células PC12 , Fragmentos de Peptídeos/metabolismo , Polifenóis/metabolismo , Conformação Proteica , Ratos , Estilbenos/metabolismo
14.
J Nat Prod ; 77(2): 213-7, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24521157

RESUMO

Stilbenes have received much attention during the last two decades following the discovery of resveratrol in wine. Since then, there have been a growing number of papers reporting various biological activities of naturally occurring stilbenes. The aim of this study was to determine new minor stilbenes from Vitis vinifera stalks. Purification of these compounds was achieved by means of centrifugal partition chromatography, a versatile separation technique that does not require a solid stationary phase. Viniphenol A (1), a new resveratrol hexamer, was isolated along with five oligostilbenoids identified in V. vinifera for the first time, ampelopsin C, davidiol A, leachianol F, leachianol G, and E-maackin, a dimer with an unusual dioxane moiety, and 14 known hydroxystilbenes. The structure and stereochemistry of viniphenol A were determined on the basis of spectroscopic data analysis and molecular modeling under NMR constraints. Viniphenol A showed protective effects against amyloid-ß-induced toxicity in PC12 cell cultures.


Assuntos
Estilbenos/isolamento & purificação , Estilbenos/farmacologia , Vitis/química , Peptídeos beta-Amiloides/farmacologia , Animais , Antioxidantes/farmacologia , Catequina/farmacologia , Dioxanos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Células PC12 , Ratos , Resveratrol , Estilbenos/química
15.
J Nat Prod ; 77(8): 1981-5, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25093453

RESUMO

Dimeric stilbene glucosides 1-3 [two diastereomers of (-)-gnemonoside A (1a and 1b), (-)-gnemonoside C (2), and (-)-gnemonoside D (3)] as well as a mixture of the two enantiomers of gnetin C (4) were isolated from the rhizomes of Gnetum africanum. The two enantiomers of gnetin C, (+)-4 and (-)-4, were obtained from the aglycones of 1a and 1b, respectively. The configurations of these stilbenoids were investigated by NMR and vibrational circular dichroism (VCD) experiments. The absolute configurations of (-)-1a, (-)-2, (-)-3, and (-)-4 were established as 7aS,8aS by VCD spectroscopy in combination with density functional theory calculations. The antiamyloidogenic activity of the isolated stilbenes was also evaluated versus beta-amyloid fibrils. The four glucosides of gnetin C (1a, 1b, 2, and 3) were found to be the most active compounds, with inhibition percentages of 56, 56, 58, and 54 at 10 µM, respectively.


Assuntos
Glucosídeos/química , Gnetum/química , Fármacos Neuroprotetores/isolamento & purificação , Estilbenos/química , Benzofuranos/química , Benzofuranos/isolamento & purificação , Camarões , Dicroísmo Circular , Glucosídeos/isolamento & purificação , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Ressonância Magnética Nuclear Biomolecular , Rizoma/química , Estereoisomerismo , Estilbenos/isolamento & purificação
16.
J Agric Food Chem ; 72(17): 9621-9636, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648422

RESUMO

This study focuses on countering Fusarium graminearum, a harmful fungal pathogen impacting cereal crops and human health through mycotoxin production. These mycotoxins, categorized as type B trichothecenes, pose significant health risks. Research explores natural alternatives to synthetic fungicides, particularly investigating phenolics in grapevine byproducts. Thirteen eco-extracts from five French grape varieties (Merlot, Cabernet Sauvignon, Sauvignon blanc, Tannat, and Artaban) exhibited substantial antifungal properties, with ten extracts displaying remarkable effects. Extracts from grapevine stems and roots notably reduced fungal growth by over 91% after five days. Through UHPLC-HRMS/MS analysis and metabolomics, the study identified potent antifungal compounds such as ampelopsin A and cyphostemmin B, among other oligomeric stilbenes. Interestingly, this approach showed that flavan-3-ols have been identified as markers for extracts that induce fungal growth. Root extracts from rootstocks, rich in oligostilbenes, demonstrated the highest antifungal activity. This research underscores grapevine byproducts' potential both as a sustainable approach to control F. graminearum and mycotoxin contamination in cereal crops and the presence of different metabolites from the cultivars of grapevine, suggesting different activities.


Assuntos
Fusarium , Extratos Vegetais , Espectrometria de Massas em Tandem , Vitis , Vitis/química , Vitis/microbiologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Doenças das Plantas/microbiologia , Resíduos/análise
17.
RSC Adv ; 14(7): 4654-4665, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38318626

RESUMO

Despite all the significant progresses made to enhance the efficacy of the existing bank of drugs used to manage and cure type II diabetes mellitus, there is still a need to search and develop novel bioactive compounds with superior efficacy and minimal adverse effects. This study describes the valorization of the natural bioactive sesquiterpene coumarin via the semi-synthesis of new analogs and the study of their α-amylase inhibition activity. The sesquiterpene coumarin named coladonin (1) was quantitatively isolated from the chloroform extract of endemic Ferula tunetana roots. Subsequently, the oxidation of 1via the Jones oxidation reaction, used as a key reaction, afforded precursor 2. The condensation of oxidized coladonin (2) with various aryl aldehydes provided a series of new arylidene-based sesquiterpene coumarin derivatives (3a-m), which were characterized by NMR and ESI-HRMS experiments. All derivatives evaluated in vitro for their α-amylase inhibitory potential showed interesting α-amylase inhibition with IC50 values ranging from 7.24 to 28.98 µM. Notably, compounds 3k and 3m exhibited lower IC50 values (7.24 µM and 8.38 µM, respectively) compared to the standard (acarbose: IC50 = 9.83 µM). In addition, the structure-activity relationship (SAR) for all the compounds was studied. The most active compounds were found to be mixed-type inhibitors, which was revealed by kinetic studies. Furthermore, molecular in silico docking studies were established for all synthesized analogs with the binding site for the α-amylase enzyme.

18.
Planta Med ; 79(11): 966-70, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23807809

RESUMO

Microglia-driven inflammatory processes are thought to play an important role in ageing and several neurological disorders. Since consumption of a diet rich in polyphenols has been associated with anti-inflammatory and neuroprotective effects, we studied the effects of twenty-five stilbenoids isolated from Milicia excelsa, Morus alba, Gnetum africanum, and Vitis vinifera. These compounds were tested at 5 and 10 µM on BV-2 microglial cells stimulated with bacterial lipopolysaccharide. Ten stilbenoids reduced lipopolysaccharide-induced nitric oxide production at 5 and/or 10 µM. Two tetramers, E-vitisin A and E-vitisin B, were the most effective molecules. Moreover, they attenuated the expression of the inducible NO synthase protein and gene.


Assuntos
Anti-Inflamatórios/farmacologia , Gnetum/química , Moraceae/química , Morus/química , Fármacos Neuroprotetores/farmacologia , Estilbenos/farmacologia , Vitis/química , Animais , Anti-Inflamatórios/química , Benzofuranos/química , Benzofuranos/isolamento & purificação , Benzofuranos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fármacos Neuroprotetores/química , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Caules de Planta/química , Polifenóis/farmacologia , Estilbenos/química , Estilbenos/isolamento & purificação
19.
Phytochemistry ; 206: 113504, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36403669

RESUMO

Phytochemical investigation of the underground parts of Arundina graminifolia D.Don Hochr was conducted leading to the isolation of nine new glucosyloxybenzyl 2R-benzylmalate and two new glucosyloxybenzyl 2R-isobutylmalate derivatives. The compounds were purified using chromatographic techniques and their structures were deduced based on spectroscopic techniques including nuclear magnetic resonance and high-resolution mass spectrometry as well as comparing with previous literature. The antioxidant activities of the isolated compounds were also evaluated. The compounds showed potent antioxidant activities in the ABTS radical scavenging, DPPH radical scavenging and FRAP activities. Furthermore, the isolated compounds were observed to exert minimal cytotoxic effects against RAW 264.7 cell, suggesting biocompatibility as well as cytoprotective effects against hydrogen peroxide induced cell toxicity.


Assuntos
Antineoplásicos , Orchidaceae , Antioxidantes/farmacologia , Estrutura Molecular , Espectroscopia de Ressonância Magnética , Orchidaceae/química
20.
Food Chem ; 393: 133359, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35671662

RESUMO

Determination of stereochemistry and enantiomeric excess in chiral natural molecules is a research of great interest because enantiomers can exhibit different biological activities. Viniferin stilbene dimers are natural molecules present in grape berries and wine but also, in larger amount, in stalks of grapevine. Four stereoisomers of viniferin stilbene dimers (7aS,8aS)-E-ε-viniferin (1a), (7aR,8aR)-E-ε-viniferin (1b), (7aS,8aR)-E-ω-viniferin (2a), and (7aR,8aS)-E-ω-viniferin (2b) were isolated from grapevine stalks of Cabernet Sauvignon, Merlot and Sauvignon Blanc, using a combination of centrifugal partition chromatography (CPC), preparative and chiral HPLC. The structure elucidation of these molecules was achieved by NMR whereas the absolute configurations of the four stereoisomers were investigated by vibrational circular dichroism spectroscopy in combination with density functional theory (DFT) calculations. This study unambiguously established the (+)-(7aS,8aS) and (+)-(7aR,8aS) configurations for E-ε-viniferin and E-ω-viniferin, respectively. Finally, we show that Cabernet Sauvignon provided the quasi enantiopure (+)-(7aS,8aS)-E-ε-viniferin compound which presents the best anti-inflammatory and anti-oxidant activities.


Assuntos
Estilbenos , Vitis , Vinho , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Estereoisomerismo , Estilbenos/química , Vitis/química , Vinho/análise
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