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1.
Plant Mol Biol ; 104(3): 309-325, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32833148

RESUMO

KEY MESSAGE: FtMYB18 plays a role in the repression of anthocyanins and proanthocyanidins accumulation by strongly down-regulating the CHS and DFR genes in Tartary buckwheat, and the C5 motif plays an important role in this process. Anthocyanins and proanthocyanidins (PAs) are important flavonoids in Tartary buckwheat (Fagopyrum tataricum Gaertn.), which provides various vibrant color and stronge abiotic stress resistance. Their synthesis is generally regulated by MYB transcription factors at transcription level. However, the negative regulations of MYB and their effects on flavonol metabolism are poorly understood. A SG4-like MYB subfamily TF, FtMYB18, containing C5 motif was identified from Tartary buckwheat. The expression of FtMYB18 was not only showed a negative correlation with anthocyanins and PAs content but also strongly respond to MeJA and ABA. As far as the transgenic lines with FtMYB18 overexpression, anthocyanins and PAs accumulations were decreased through down-regulating expression levels of NtCHS and NtDFR in tobacco, AtDFR and AtTT12 in Arabidopsis, FtCHS, FtDFR and FtANS in Tartary buckwheat hairy roots, respectively. However, FtMYB18 showed no effect on the FLS gene expression and the metabolites content in flavonol synthesis branch. The further molecular interaction analysis indicated FtMYB18 could mediate the inhibition of anthocyanins and PAs synthesis by forming MBW transcriptional complex with FtTT8 and FtTTG1, or MYB-JAZ complex with FtJAZ1/-3/-4/-7. Importantly, in FtMYB18 mutant lines with C5 motif deletion (FtMYB18-C), both of anthocyanins and PAs accumulations had recovered to the similar level as that in wild type, which was attributed to the weakened MBW complex activity or the deficient molecular interaction between FtMYB18ΔC5 with FtJAZ3/-4. The results showed that FtMYB18 could suppress anthocyanins and PAs synthesis at transcription level through the specific interaction of C5 motif with other proteins in Tartary buckwheat.


Assuntos
Antocianinas/biossíntese , Fagopyrum/metabolismo , Proteínas de Plantas/metabolismo , Proantocianidinas/biossíntese , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis , Fagopyrum/genética , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Estresse Fisiológico , Tabaco/genética , Fatores de Transcrição/química
2.
Food Chem ; 332: 127412, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623128

RESUMO

In this study, metabolomics and proteomics were employed to investigate the change mechanism of nonvolatile compounds during white tea processing. A total of 99 nonvolatile compounds were identified, among which the contents of 13 free amino acids, caffeine, theaflavins, 7 nucleosides and nucleotides, and 5 flavone glycosides increased significantly, while the contents of theanine, catechins, theasinesins, 3 proanthocyanidins, and phenolic acids decreased significantly during the withering period. The results of proteomics indicated that the degradation of proteins accounted for the increase in free amino acid levels; the weakened biosynthesis, in addition to oxidation, also contributed to the decrease in flavonoid levels; the degradation of ribonucleic acids contributed to the increase in nucleoside and nucleotide levels during the withering period. In addition, the drying process was found to slightly promote the formation of white tea taste. Our study provides a novel characterization of white tea taste formation during processing.


Assuntos
Camellia sinensis/química , Metabolômica/métodos , Chá/química , Alcaloides/análise , Alcaloides/metabolismo , Camellia sinensis/metabolismo , Catecóis/análise , Catecóis/metabolismo , Flavonoides/análise , Flavonoides/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Proteômica , Chá/metabolismo
3.
PLoS One ; 15(7): e0235975, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32649704

RESUMO

Rice cultivar "Weiyou916" (Oryza sativa L. ssp. Indica) were cultured with control (10 mM NO3-) and nitrate deficient solution (0 mM NO3-) for four weeks. Nitrogen (N) deficiency significantly decreased the content of N and P, dry weight (DW) of the shoots and roots, but increased the ratio of root to shoot in O. sativa. N deficiency decreased the photosynthesis rate and the maximum quantum yield of primary photochemistry (Fv/Fm), however, increased the intercellular CO2 concentration and primary fluorescence (Fo). N deficiency significantly increased the production of H2O2 and membrane lipid peroxidation revealed as increased MDA content in O. sativa leaves. N deficiency significantly increased the contents of starch, sucrose, fructose, and malate, but did not change that of glucose and total soluble protein in O. sativa leaves. The accumulated carbohydrates and H2O2 might further accelerate biosynthesis of lignin in O. sativa leaves under N limitation. A total of 1635 genes showed differential expression in response to N deficiency revealed by Illumina sequencing. Gene Ontology (GO) analysis showed that 195 DEGs were found to highly enrich in nine GO terms. Most of DEGs involved in photosynthesis, biosynthesis of ethylene and gibberellins were downregulated, whereas most of DEGs involved in cellular transport, lignin biosynthesis and flavonoid metabolism were upregulated by N deficiency in O. sativa leaves. Results of real-time quantitative PCR (RT-qPCR) further verified the RNA-Seq data. For the first time, DEGs involved oxygen-evolving complex, phosphorus response and lignin biosynthesis were identified in rice leaves. Our RNA-Seq data provided a global view of transcriptomic profile of principal processes implicated in the adaptation of N deficiency in O. sativa and shed light on the candidate direction in rice breeding for green and sustainable agriculture.


Assuntos
Flavonoides/metabolismo , Lignina/metabolismo , Nitratos/metabolismo , Oryza/genética , Fotossíntese , Carboidratos/análise , Clorofila A/química , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oryza/metabolismo , Oxirredução , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , RNA de Plantas/química , RNA de Plantas/metabolismo , Análise de Sequência de RNA
4.
Arch Biochem Biophys ; 690: 108471, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32622788

RESUMO

Stilbenes, an active substances closely related to resistance and quality of grapes, are rarely found in natural resources. However its cumulative amount is affected by ultraviolet radiation (UV). The purpose of this study is to screen key genes in biosynthesis of stilbenes Trans-scripusin A and explore its synthetic pathway. We tested content of stilbenes with UHPLC-QQQ-MS2, results revealed that stilbenes accumulation is positively correlated with UV-B exposure time. Then, we performed transcriptome high-throughput sequencing of grapes under treatments. Results shown that 13,906 differentially expressed genes were obtained, which were mainly enriched in three major regions (ribosome, plant-pathogen interaction and biosynthesis of flavonoid). Three genes of trans-scripusin A synthesis pathway key got by combining KEGG annotation and reference gene HsCYP1B1. Phylogenetic analysis showed that SAH genes had high homology with other hydroxylase genes, and distributed in two subgroups. Gene structure analysis showed that SAH genes contained four exons, indicating that gene has low genetic diversity. Chromosome localization revealed that SAH genes were distributed on different chromosomes, in addition, the number of gene pairs between Vitis vinifera and other species was not related to genome size of other species. The expression profiles of SAH genes in different parts of Vitis vinifera L. were analyzed using qRT-PCR analysis, results indicated that expression of SAH genes be specific to fruit part. These paper provide theoretical basis for further study of polyphenols biosynthesis pathway in grape fruits. The study provides novel insights for further understanding quality of grapes response to UV radiation.


Assuntos
Frutas/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , RNA Mensageiro/efeitos da radiação , Vitis/genética , Vias Biossintéticas , Cromatografia Líquida de Alta Pressão , Flavonoides/metabolismo , Frutas/metabolismo , Frutas/efeitos da radiação , Ensaios de Triagem em Larga Escala , Conformação de Ácido Nucleico , Filogenia , Polifenóis/metabolismo , RNA-Seq , Ribossomos/metabolismo , Estilbenos/metabolismo , Estresse Fisiológico/genética , Estresse Fisiológico/efeitos da radiação , Espectrometria de Massas em Tandem , Transcriptoma/efeitos da radiação , Raios Ultravioleta , Vitis/metabolismo , Vitis/efeitos da radiação
5.
Ecotoxicol Environ Saf ; 201: 110832, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32563158

RESUMO

Ozone (O3), an oxidizing toxic air pollutant, is ubiquitous in industrialized and developing countries. To understand the effects of O3 exposure on apple (Malus) and to explore its defense mechanisms, we exposed 'Hongjiu' crabapple to O3 and monitored its responses using physiological, transcriptomics, and metabolomics analyses. Exposure to 300 nL L-1 O3 for 3 h caused obvious damage to the leaves of Malus crabapple, affected chlorophyll and anthocyanin contents, and activated antioxidant enzymes. The gene encoding phospholipase A was highly responsive to O3 in Malus crabapple. McWRKY75 is a key transcription factor in the response to O3 stress, and its transcript levels were positively correlated with those of flavonoid-related structural genes (McC4H, McDFR, and McANR). The ethylene response factors McERF019 and McERF109-like were also up-regulated by O3. Exogenous methyl jasmonate (MeJA) decreased the damaging effects of O3 on crabapple and was most effective at 200 µmol L -1. Treatments with MeJA altered the metabolic pathways of crabapple under O3 stress. In particular, MeJA activated the flavonoid metabolic pathway in Malus, which improved its resistance to O3 stress.


Assuntos
Acetatos/farmacologia , Poluentes Atmosféricos/toxicidade , Ciclopentanos/farmacologia , Malus , Oxilipinas/farmacologia , Ozônio/toxicidade , Reguladores de Crescimento de Planta/farmacologia , Transcriptoma/efeitos dos fármacos , Antocianinas/genética , Antocianinas/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Flavonoides/metabolismo , Malus/efeitos dos fármacos , Malus/genética , Malus/metabolismo , Metabolômica , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/metabolismo , Fatores de Transcrição/genética
6.
PLoS One ; 15(6): e0234468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530958

RESUMO

Flavonoids are plant-derived compounds that occur abundantly in fruits and vegetables and have been shown to possess potent anti-cancer, antioxidant, and anti-inflammatory properties. However, their direct targets and molecular mechanism of action are not well characterized, hampering exploitation of the beneficial properties of flavonoids for drug development. Small ubiquitin-related modifier 1 (SUMO1) is attached to target proteins as part of a post-translational modification system implicated in a myriad of cellular processes from nuclear trafficking to transcriptional regulation. Using a combination of surface plasmon resonance, differential scanning fluorimetry and fluorescence quenching studies, we provide evidence for direct binding of the dietary flavonoid fisetin to human SUMO1. Our NMR chemical shift perturbation analyses reveal that binding to fisetin involves four conserved amino acid residues (L65, F66, E67, M82) previously shown to be important for conjugation of SUMO1 to target proteins. In vitro sumoylation experiments indicate that fisetin blocks sumoylation of tumor suppressor p53, consistent with fisetin negatively affecting post-translational modification and thus the biological activity of p53. A series of differential scanning fluorimetry experiments suggest that high concentrations of fisetin result in destabilization and unfolding of SUMO1, presenting a molecular mechanism by which flavonoid binding affects its activity. Overall, our data establish a novel direct interaction between fisetin and SUMO1, providing a mechanistic explanation for the ability of fisetin to modulate multiple key signaling pathways inside cells.


Assuntos
Flavonoides/metabolismo , Flavonoides/farmacologia , Proteína SUMO-1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Dieta , Humanos , Ligação Proteica , Saccharomyces cerevisiae , Sumoilação/efeitos dos fármacos
7.
Chem Biol Interact ; 327: 109186, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32590071

RESUMO

In this study, we scrutinized the anticancer effects of FB-15 on human gastric carcinoma MGC-803 cells in vitro and vivo, and its preliminary effect on tubulin and HIF-1α. We confirmed that FB-15 not only inhibited the proliferation of a large number of cells in a concentration and time-dependent manner but also inhibited proliferation of a single cell to form clones. FB-15 manifested little cytotoxicity for normal stomach cells GES-1. The flow cytometry analysis displayed that FB-15 induced apoptosis MGC-803 cells and mainly arrested cells in the S phase in a concentration-dependent manner. The results of the wound healing assay indicated that FB-15 suppressed cell migration. Furthermore, the western blotting showed that FB-15 down-regulated the expression of ß3-tubulin and HIF-1α, consistent with Immunohistochemical assay. The binding modes of FB-15 with tubulin were clarified by molecular docking. FB-15 significantly suppressed the growth of MGC-803 gastric cancer tumors. The inhibitory effect of FB-15 on tumor growth was superior to 5-Fu. Taken together, these results provided evidence for FB-15 to be used as an effective anticancer drug candidate for gastric cancer.


Assuntos
Antineoplásicos/uso terapêutico , Benzimidazóis/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Flavonoides/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzimidazóis/metabolismo , Benzimidazóis/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Flavonoides/metabolismo , Flavonoides/farmacologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Simulação de Acoplamento Molecular , Ligação Proteica , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Neoplasias Gástricas/patologia , Tubulina (Proteína)/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Life Sci ; 257: 118010, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32598932

RESUMO

Podocyte injury is an early event and core in the development of focal segmental glomerular sclerosis (FSGS) that induces poor prognosis. Epithelial-mesenchymal transition (EMT) as a response of podocyte to injury leads to podocyte depletion and proteinuria. The abnormally reactivated NOTCH pathway may be involved in podocyte EMT. Baicalin, as a natural flavonoid compound, had significant inhibitory activity on tissue fibrosis and tumor cell invasion. However, its potential role and molecular mechanisms to injured podocyte in FSGS are little known. Here we found that baicalin could inhibit podocyte EMT markers expression and cell migration induced by TGF-ß1, accompanied by the up-regulated expression of slit diaphragm (SD) proteins and cell-cell adhesion molecule. Further investigation revealed that EMT inhibition of baicalin on injured podocyte is mainly mediated by the reduction of notch1 activation and its downstream Snail expression. Using the adriamycin-induced FSGS model, we determined that baicalin suppresses the Notch1-Snail axis activation in podocytes, relieves glomerulus structural disruption and dysfunction, and reduces proteinuria. Altogether, these findings suggest that baicalin is a novel renoprotective agent against podocyte EMT in FSGS and indicate its underlying mechanism that involves in negative regulation of the Notch1-Snail axis.


Assuntos
Flavonoides/farmacologia , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Proteinúria/tratamento farmacológico , Animais , Biomarcadores/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Doxorrubicina/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Flavonoides/metabolismo , Glomerulosclerose Segmentar e Focal/metabolismo , Glomérulos Renais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Podócitos/metabolismo , Proteinúria/metabolismo , Receptor Notch1/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
9.
PLoS One ; 15(6): e0233963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530961

RESUMO

Eclipta alba L., also known as false daisy, is well known and commercially attractive plant with excellent hepatotoxic and antidiabetic activities. Light is considered a key modulator in plant morphogenesis and survival by regulating important physiological cascades. Current study was carried out to investigate growth and developmental aspects of E. alba under differential effect of multispectral lights. In vitro derived callus culture of E. alba was exposed to multispectral monochromatic lights under controlled aseptic conditions. Maximum dry weight was recorded in culture grown under red light (11.2 g/L) whereas negative effect was observed under exposure of yellow light on callus growth (4.87 g/L). Furthermore, red light significantly enhanced phenolics and flavonoids content (TPC: 57.8 mg/g, TFC: 11.1 mg/g) in callus cultures compared to rest of lights. HPLC analysis further confirmed highest accumulation of four major compounds i.e. coumarin (1.26 mg/g), eclalbatin (5.00 mg/g), wedelolactone (32.54 mg/g) and demethylwedelolactone (23.67 mg/g) and two minor compounds (ß-amyrin: 0.38 mg/g, luteolin: 0.39 mg/g) in red light treated culture whereas stigmasterol was found optimum (0.22 mg/g) under blue light. In vitro based biological activities including antioxidant, antidiabetic and lipase inhibitory assays showed optimum values in cultures exposed to red light, suggesting crucial role of these phytochemicals in the enhancement of the therapeutic potential of E. alba. These results clearly revealed that the use of multispectral lights in in vitro cultures could be an effective strategy for enhanced production of phytochemicals.


Assuntos
Antioxidantes/metabolismo , Eclipta/metabolismo , Eclipta/efeitos da radiação , Hipoglicemiantes/metabolismo , Compostos Fitoquímicos/metabolismo , Antioxidantes/química , Cumarínicos/metabolismo , Eclipta/crescimento & desenvolvimento , Flavonoides/metabolismo , Hipoglicemiantes/química , Luz , Fenóis/metabolismo , Compostos Fitoquímicos/química , Metabolismo Secundário/efeitos da radiação , Técnicas de Cultura de Tecidos
10.
Nat Commun ; 11(1): 2629, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457405

RESUMO

Grain size is an important component trait of grain yield, which is frequently threatened by abiotic stress. However, little is known about how grain yield and abiotic stress tolerance are regulated. Here, we characterize GSA1, a quantitative trait locus (QTL) regulating grain size and abiotic stress tolerance associated with metabolic flux redirection. GSA1 encodes a UDP-glucosyltransferase, which exhibits glucosyltransferase activity toward flavonoids and monolignols. GSA1 regulates grain size by modulating cell proliferation and expansion, which are regulated by flavonoid-mediated auxin levels and related gene expression. GSA1 is required for the redirection of metabolic flux from lignin biosynthesis to flavonoid biosynthesis under abiotic stress and the accumulation of flavonoid glycosides, which protect rice against abiotic stress. GSA1 overexpression results in larger grains and enhanced abiotic stress tolerance. Our findings provide insights into the regulation of grain size and abiotic stress tolerance associated with metabolic flux redirection and a potential means to improve crops.


Assuntos
Adaptação Fisiológica , Grão Comestível/metabolismo , Glucosiltransferases/metabolismo , Oryza/metabolismo , Crescimento Celular , Proliferação de Células , Grão Comestível/citologia , Grão Comestível/genética , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/genética , Redes e Vias Metabólicas , Oryza/citologia , Oryza/genética , Fenilpropionatos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas
11.
Food Chem ; 327: 127045, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464460

RESUMO

In this study, the inhibitory potentials of food originated 34 phenolic acids, and flavonoid compounds were screened against acetylcholinesterase, butyrylcholinesterase, urease, and tyrosinase enzymes. All compounds included in this study exhibited high antioxidant activity with an ignorable cytotoxic activity. In general, they also showed poor anti-urease and anti-tyrosinase activities. Compounds in aglycone form (quercetin, myricetin, chrysin, and luteolin) showed strong anticholinesterase activities. No relation was observed between the tested bioactivities except from the case that aglycone compounds exhibited a strong positive relationship between antioxidant activities and anticholinesterase activity. Interestingly, there was a relation between the molecular weights of aglycone compounds and their anticholinesterase activities. The study showed that flavonoids with molecular mass of 250-320 g/mol have high potential of anticholinesterase activities and are valuable for future experiments on animals and humans. Potential inhibitory effects of these molecules on target proteins were investigated using docking and molecular dynamics calculations.


Assuntos
Inibidores da Colinesterase/química , Flavonoides/química , Hidroxibenzoatos/química , Plantas Comestíveis/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/química , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Flavonoides/metabolismo , Flavonoides/farmacologia , Humanos , Hidroxibenzoatos/metabolismo , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Plantas Comestíveis/metabolismo
12.
Proc Natl Acad Sci U S A ; 117(22): 12017-12028, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32434917

RESUMO

Synthetic chemical elicitors, so called plant strengtheners, can protect plants from pests and pathogens. Most plant strengtheners act by modifying defense signaling pathways, and little is known about other mechanisms by which they may increase plant resistance. Moreover, whether plant strengtheners that enhance insect resistance actually enhance crop yields is often unclear. Here, we uncover how a mechanism by which 4-fluorophenoxyacetic acid (4-FPA) protects cereals from piercing-sucking insects and thereby increases rice yield in the field. Four-FPA does not stimulate hormonal signaling, but modulates the production of peroxidases, H2O2, and flavonoids and directly triggers the formation of flavonoid polymers. The increased deposition of phenolic polymers in rice parenchyma cells of 4-FPA-treated plants is associated with a decreased capacity of the white-backed planthopper (WBPH) Sogatella furcifera to reach the plant phloem. We demonstrate that application of 4-PFA in the field enhances rice yield by reducing the abundance of, and damage caused by, insect pests. We demonstrate that 4-FPA also increases the resistance of other major cereals such as wheat and barley to piercing-sucking insect pests. This study unravels a mode of action by which plant strengtheners can suppress herbivores and increase crop yield. We postulate that this represents a conserved defense mechanism of plants against piercing-sucking insect pests, at least in cereals.


Assuntos
Acetatos/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Flavonoides , Hemípteros , Imunidade Vegetal/efeitos dos fármacos , Animais , Bioensaio , Produtos Agrícolas/efeitos dos fármacos , Flavonoides/análise , Flavonoides/metabolismo , Herbivoria , Hordeum/efeitos dos fármacos , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/metabolismo , Oryza/efeitos dos fármacos , Peroxidases/análise , Peroxidases/metabolismo , Controle de Pragas/métodos , Folhas de Planta/química , Triticum/efeitos dos fármacos
13.
Food Chem ; 326: 126985, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32413764

RESUMO

This study aims to investigate the effects of fermentation on the phenolic components and their bioaccessibility in extruded brown rice (EBR). The saccharified solution of EBR (SS-EBR) depicted higher phenolics when fermented by single or co-culture of Lactobacillusplantarum, Lactobacillus fermentum and Saccharomyces cerevisiae for 24 h at 37 °C. The co-culture fermented SS-EBR more significantly enhanced free, conjugated and bound phenolics and flavonoids with total increment of 93.3% and 61.3%, respectively. Fermentation changed the contents and compositions of phenolics in each fraction with more than 10-fold increase in vanillic acid and quercetin contents. Ferulic, p-cumaric and chlorogenic acids were increased by 83.5%, 52.2% and 113.4%, respectively, while kaempferol and cinnamic acid were found only in fermented SS-EBR. Fermentation also improved the oxygen radical absorption capacity (ORAC) and the bioaccessible phenolics in SS-EBR. Hence, the co-culture fermented SS-EBR, can be utilized as a functional supplement to provide more bioaccessible antioxidants.


Assuntos
Lactobacillus/crescimento & desenvolvimento , Oryza/química , Fenóis/química , Saccharomyces cerevisiae/crescimento & desenvolvimento , Antioxidantes/metabolismo , Técnicas de Cultura Celular por Lotes , Flavonoides/metabolismo , Oryza/metabolismo , Fenóis/metabolismo , Quercetina/metabolismo , Saccharomyces cerevisiae/metabolismo , Ácido Vanílico/metabolismo
14.
J Chem Ecol ; 46(4): 442-454, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32314119

RESUMO

Elevational gradients affect the production of plant secondary metabolites through changes in both biotic and abiotic conditions. Previous studies have suggested both elevational increases and decreases in host-plant chemical defences. We analysed the correlation of alkaloids and polyphenols with elevation in a community of nine Ficus species along a continuously forested elevational gradient in Papua New Guinea. We sampled 204 insect species feeding on the leaves of these hosts and correlated their community structure to the focal compounds. Additionally, we explored species richness of folivorous mammals along the gradient. When we accounted for Ficus species identity, we found a general elevational increase in flavonoids and alkaloids. Elevational trends in non-flavonol polyphenols were less pronounced or showed non-linear correlations with elevation. Polyphenols responded more strongly to changes in temperature and humidity than alkaloids. The abundance of insect herbivores decreased with elevation, while the species richness of folivorous mammals showed an elevational increase. Insect community structure was affected mainly by alkaloid concentration and diversity. Although our results show an elevational increase in several groups of metabolites, the drivers behind these trends likely differ. Flavonoids may provide figs with protection against abiotic stressors. In contrast, alkaloids affect insect herbivores and may provide protection against mammalian herbivores and pathogens. Concurrent analysis of multiple compound groups alongside ecological data is an important approach for understanding the selective landscape that shapes plant defences.


Assuntos
Alcaloides/metabolismo , Altitude , Ficus/química , Flavonoides/metabolismo , Cadeia Alimentar , Herbivoria , Feromônios/análise , Animais , Biota , Insetos/fisiologia , Mamíferos/fisiologia , Papua Nova Guiné , Folhas de Planta/química
15.
Xenobiotica ; 50(10): 1158-1169, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32312164

RESUMO

2'-, 3'-, and 4'-Methoxyflavones (MeFs) were incubated with nine forms of recombinant human cytochrome P450 (P450 or CYP) enzymes in the presence of an NADPH-generating system and the products formed were analyzed with LC-MS/MS methods.CYP1B1.1 and 1B1.3 were highly active in demethylating 4'MeF to form 4'-hydroxyflavone (rate of 5.0 nmol/min/nmol P450) and further to 3',4'-dihydroxyflavone (rates of 2.1 and 0.66 nmol/min/nmol P450, respectively). 3'MeF was found to be oxidized by P450s to m/z 239 (M-14) products (presumably 3'-hydroxyflavone) and then to 3',4'-dihydroxyflavone. P450s also catalyzed oxidation of 2'MeF to m/z 239 (M-14) and m/z 255 (M-14, M-14 + 16) products, presumably mono- and di-hydroxylated products, respectively.At least two types of ring oxidation products having m/z 269 fragments were formed, although at slower rates than the formation of mono- and di-hydroxylated products, on incubation of these MeFs with P450s; one type was products oxidized at the C-ring, having m/z 121 fragments, and the other one was the products oxidized at the A-ring (having m/z 137 fragments).Molecular docking analysis indicated the preference of interaction of O-methoxy moiety of methoxyflavones in the active site of CYP1A2.These results suggest that 2'-, 3'-, and 4'-methoxyflavones are principally demethylated by human P450s to form mono- and di-hydroxyflavones and that direct oxidation occurs in these MeFs to form mono-hydroxylated products, oxidized at the A- or B-ring of MeF.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Flavonoides/metabolismo , Cromatografia Líquida , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP1B1 , Desmetilação , Hidroxilação , Cinética , Microssomos Hepáticos , Simulação de Acoplamento Molecular , Espectrometria de Massas em Tandem
16.
Food Chem ; 320: 126617, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32247167

RESUMO

Tricin (5,7,4'-trihydroxy-3',5'-dimethoxyflavone) as a renewable and bioactive polyphenolic compound is widely distributed in monocots with free and conjugated forms. It is derived from the secondary metabolite of plants with an analogous biosynthetic pathway to other flavonoids. Due to its unique biological properties over other flavonoids, tricin has been linked to numerous health benefits for human nutrition. In recent years, tricin has been demonstrated to have excellent pharmacological bioactivities and has been proposed as a safe candidate for cancer chemoprevention. For throwing light on the structure-activity relationship of tricin monomer and its potential clinical application, the natural occurrence, physicochemical characteristics, bio/chemosynthesis, isolation and purification, biological properties involved metabolism in vitro and in vivo of tricin as well as its toxicology and bioavailability are critically reviewed, which aims at greatly moving forward the value-added applications of this natural bioactive material on food, human nutrition, and pharmacology.


Assuntos
Flavonoides/metabolismo , Poaceae/metabolismo , Disponibilidade Biológica , Vias Biossintéticas , Flavonoides/química , Humanos , Poaceae/química , Relação Estrutura-Atividade
17.
PLoS One ; 15(4): e0231543, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32282828

RESUMO

Dipeptidyl peptidase-4 (DPP-4) is a proteolytic enzyme responsible for the rapid degradation of Glucagon-like peptide 1 (GLP-1) that is required for the secretion of insulin. DPP-4 also influences activation of node like receptor family, pyrin domain containing 3 (NLRP3) inflammasome under diabetic conditions. Although several polyphenols are reported for various bioactivities, they are consumed as part of the food matrix and not in isolation. Horsegram (Macrotyloma uniflorum) is a rich source of myricetin (Myr) (35 µg/g flour), reported for its anti-hyperglycemic effect. In this investigation, we aimed to study the effect of Myr, singly, and in the presence of co-nutrient horsegram protein (HP) on DPP-4 activity and its consequential impact on GLP-1, insulin, and NLRP3 inflammasome in high-fat diet and single low dose streptozotocin (STZ)-induced diabetic male Wistar rats. In diabetic control (DC), the activity of DPP-4 and its expression were higher compared to treated groups. The consequential decrease in the circulating GLP-1 levels in the DC group, but not treated groups, further indicated the effectiveness of our test molecules under diabetic conditions. Specifically, Myr decreased DPP-4 activity and its expression levels with enhanced circulating GLP-1 and insulin levels. Myr administration also resulted in a lessening of diabetes-induced NLRP3 inflammasome activation and enhanced antioxidant enzyme activities. HP also proved to be efficient in reducing elevated blood glucose levels and enhancing antioxidant enzyme activities. However, Myr, in the presence of HP as a co-nutrient, had diminished capacity to inhibit DPP-4 and, consequently, reduced potential in ameliorating diabetic conditions. Myr proved to be a potent inhibitor of DPP-4 in vitro and in vivo, resulting in enhanced circulating GLP-1 and insulin levels, thereby improving diabetic conditions. Though Myr and HP, individually ameliorate diabetic conditions, their dietary combination had reduced efficiency.


Assuntos
Diabetes Mellitus Experimental/terapia , Dipeptidil Peptidase 4/metabolismo , Flavonoides/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Hipoglicemiantes/administração & dosagem , Proteínas de Plantas/administração & dosagem , Animais , Antioxidantes/metabolismo , Glicemia , Diabetes Mellitus Experimental/metabolismo , Fabaceae , Feminino , Flavonoides/metabolismo , Inflamassomos/metabolismo , Insulina/sangue , Fígado/enzimologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Gravidez , Ratos Wistar
18.
PLoS One ; 15(4): e0232159, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32339211

RESUMO

In this study, we investigated changes in the isoflavone content, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activities (DPPH, ABTS), and anti-inflammatory activities of small-seeded and large-seeded soybean cultivars during germination (light/dark conditions). Total isoflavone content was higher at the seed stage in large-seeded soybeans, while it increased after 7 days of germination in small-seeded soybeans, particularly in response to light conditions, under which they had high TPC, TFC, and antioxidant activities. In large-seeded soybeans, the germination environment did not significantly affect TFC or DPPH inhibition, whereas TPC and ABTS inhibition were high under dark germination conditions. Extracts of sprouts exhibited superior anti-inflammatory activities. Nitric oxide production was slightly lower in small-seeded and large-seeded soybeans germinated under light and dark conditions, respectively. Our findings indicate that germinated soybeans improved nutritionally, and that enhancement of bioactivity under different germination environments could contribute to the selection of appropriate soybean cultivars.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Flavonoides/metabolismo , Germinação/fisiologia , Isoflavonas/metabolismo , Fenóis/metabolismo , Soja/metabolismo , Óxido Nítrico/metabolismo , Sementes/metabolismo , Sementes/fisiologia
19.
PLoS One ; 15(4): e0220097, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310943

RESUMO

Pulsed light, as a postharvest technology, is an alternative to traditional fungicides, and can be used on a wide variety of fruit and vegetables for sanitization or pathogen control. In addition to these applications, other effects also are detected in vegetal cells, including changes in metabolism and secondary metabolite production, which directly affect disease control response mechanisms. This study aimed to evaluate pulsed ultraviolet light in controlling postharvest rot, caused by Fusarium pallidoroseum in 'Spanish' melon, in natura, and its implications in disease control as a function of metabolomic variation to fungicidal or fungistatic effects. The dose of pulsed light (PL) that inhibited F. pallidoroseum growth in melons (Cucumis melo var. Spanish) was 9 KJ m-2. Ultra-performance liquid chromatography (UPLC) coupled to a quadrupole-time-of-flight (QTOF) mass analyzer identified 12 compounds based on tandem mass spectrometry (MS/MS) fragmentation patterns. Chemometric analysis by Principal Components Analysis (PCA) and Orthogonal Partial Least Squared Discriminant Analysis (OPLS-DA) and corresponding S-Plot were used to evaluate the changes in fruit metabolism. PL technology provided protection against postharvest disease in melons, directly inhibiting the growth of F. pallidoroseum through the upregulation of specific fruit biomarkers such as pipecolic acid (11), saponarin (7), and orientin (3), which acted as major markers for the defense system against pathogens. PL can thus be proposed as a postharvest technology to prevent chemical fungicides and may be applied to reduce the decay of melon quality during its export and storage.


Assuntos
Cucurbitaceae/microbiologia , Cucurbitaceae/efeitos da radiação , Fusarium/efeitos da radiação , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia , Apigenina/metabolismo , Cucurbitaceae/metabolismo , Flavonoides/metabolismo , Fusarium/crescimento & desenvolvimento , Glucosídeos/metabolismo , Metabolômica/métodos , Ácidos Pipecólicos/metabolismo , Raios Ultravioleta
20.
PLoS One ; 15(4): e0226537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302307

RESUMO

Enzymes of the chalcone synthase (CHS) family participate in the synthesis of multiple secondary metabolites in plants, fungi and bacteria. CHS showed a significant correlation with the accumulation patterns of anthocyanin. The peel color, which is primarily determined by the content of anthocyanin, is an economically important trait for eggplants that is affected by heat stress. A total of 7 CHS (SmCHS1-7) putative genes were identified in a genome-wide analysis of eggplants (S. melongena L.). The SmCHS genes were distributed on 7 scaffolds and were classified into 3 clusters. Phylogenetic relationship analysis showed that 73 CHS genes from 7 Solanaceae species were classified into 10 groups. SmCHS5, SmCHS6 and SmCHS7 were continuously down-regulated under 38°C and 45°C treatment, while SmCHS4 was up-regulated under 38°C but showed little change at 45°C in peel. Expression profiles of key anthocyanin biosynthesis gene families showed that the PAL, 4CL and AN11 genes were primarily expressed in all five tissues. The CHI, F3H, F3'5'H, DFR, 3GT and bHLH1 genes were expressed in flower and peel. Under heat stress, the expression level of 52 key genes were reduced. In contrast, the expression patterns of eight key genes similar to SmCHS4 were up-regulated at a treatment of 38°C for 3 hour. Comparative analysis of putative CHS protein evolutionary relationships, cis-regulatory elements, and regulatory networks indicated that SmCHS gene family has a conserved gene structure and functional diversification. SmCHS showed two or more expression patterns, these results of this study may facilitate further research to understand the regulatory mechanism governing peel color in eggplants.


Assuntos
Aciltransferases/genética , Flavonoides/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Solanum melongena/genética , Aciltransferases/metabolismo , Antocianinas/genética , Antocianinas/metabolismo , Vias Biossintéticas , Flavonoides/metabolismo , Resposta ao Choque Térmico , Família Multigênica , Filogenia , Proteínas de Plantas/metabolismo , Solanum melongena/fisiologia , Transcriptoma
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