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1.
Adv Exp Med Biol ; 1161: 243-253, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31562634

RESUMO

Flavonoids are plant secondary metabolites that act as protectants against harmful effects of UV-B radiation inasmuch as biotic stress, conferring at the same time pigmentation of fruits and leaves [67]. The term "flavonoid" refers to phenolics having a basic skeleton of diphenylpropane (C6-C3-C6), which consists of two aromatic rings linked through three carbons that usually form an oxygenated heterocycle [25, 52]. Flavonoids are broken down into several different sub-categories based on their chemical structure. The main subclasses commonly found in food items are: flavonols, flavones, flavanones, flavan-3-ols, proanthocyanidins, and anthocyanins [44, 67]. Figure 19.1 depicts the major classification of flavonoids according to their chemical structure. Their occurrence in food matrices has been extensively reviewed [39, 44], and has been subject of extensive research in the last decades. Table 19.1 contains a few examples of compounds from each of the subcategory, with the fruit (berry) in which they are commonly found. The monomeric unit of flavonoids can dimerize and polymerize to form other important high molecular weight molecules; this is the case of proanthocyanidins, that are polymers of flavan-3-ols or flavanols. Not only do these compounds act as plant protectants, but they can also be very beneficial to human health. Cohorts studies performed in the early '90 have shown that dietary consumption of flavonoids was inversely associated with morbidity and mortality from coronary heart disease [31, 32]. These findings have opened an intensive field of research on the effects of flavonoids and flavonoids-rich food extracts in cardiovascular diseases (CVD) progression, particularly in the modulating CVD-associated oxidative stress and inflammation. In this short review, we will summarize the current findings in flavonoids beneficial effects in preventing CVD through inhibition of initial stages of CVD progression. Given the magnitude of scientific literature in the field, we will focus on two strictly mechanistic aspects: inhibition of chemical-induced LDL oxidation, and the effect of flavonoids in the monocyte/macrophages activation pathways.


Assuntos
Colesterol , Flavonoides , Metabolismo dos Lipídeos , Colesterol/metabolismo , Dieta , Flavonoides/metabolismo , Humanos , Inflamação/fisiopatologia , Oxirredução
2.
Gene ; 717: 144046, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31434006

RESUMO

Flavonoids are major polyphenol compounds in plant secondary metabolism. The hydroxylation pattern of the B-ring of flavonoids is determined by the flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H). In this paper, one CsF3'H and two CsF3'5'Hs (CsF3'5'Ha and CsF3'5'Hb) were isolated. The phylogenetic tree results showed that F3'H and F3'5'Hs belong to the CYP75B and CYP75A, respectively. The Expression pattern analysis showed that the expression of CsF3'5'Ha and CsF3'5'Hb in the bud and 1st leaf were higher than other tissues. However, the CsF3'H had the highest expression in the 4th and mature leaf. The correlation analysis showed that the expression of CsF3'5'Hs is positively associated with the concentration of B-trihydroxylated catechins, and the expression of CsF3'H is positively associated with the Q contentration. Heterologous expression of these genes in yeast showed that CsF3'H and CsF3'5'Ha can catalyze flavanones, flavonols and flavanonols to the corresponding 3', 4' or 3', 4', 5'-hydroxylated compounds, for which the optimum substrate is naringenin. The enzyme of CsF3'5'Hb can only catalyze flavonols (including K and Q) and flavanonols (DHK and DHQ), of which the highest activities in catalyzing are DHK. Interestingly, The experiment of site-directed mutagenesis suggested that two novel sites near the C-terminal were discovered impacting on the activity of the CsF3'5'H. These results provide a significantly molecular basis on the accumulation B-ring hydroxylation of flavonoids in tea plant.


Assuntos
Camellia sinensis/genética , Sistema Enzimático do Citocromo P-450/genética , Flavonoides/metabolismo , Camellia sinensis/metabolismo , Clonagem Molecular , Sistema Enzimático do Citocromo P-450/metabolismo , Flavonoides/química , Regulação da Expressão Gênica de Plantas , Hidroxilação , Mutagênese Sítio-Dirigida , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética
3.
BMC Plant Biol ; 19(1): 339, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382883

RESUMO

BACKGROUND: Tartary buckwheat (Fagopyrum tataricum) is an edible cereal crop whose sprouts have been marketed and commercialized for their higher levels of anti-oxidants, including rutin and anthocyanin. UDP-glucose flavonoid glycosyltransferases (UFGTs) play an important role in the biosynthesis of flavonoids in plants. So far, few studies are available on UFGT genes that may play a role in tartary buckwheat flavonoids biosynthesis. Here, we report on the identification and functional characterization of seven UFGTs from tartary buckwheat that are potentially involved in flavonoid biosynthesis (and have varying effects on plant growth and development when overexpressed in Arabidopsis thaliana.) RESULTS: Phylogenetic analysis indicated that the potential function of the seven FtUFGT proteins, FtUFGT6, FtUFGT7, FtUFGT8, FtUFGT9, FtUFGT15, FtUFGT40, and FtUFGT41, could be divided into three Arabidopsis thaliana functional subgroups that are involved in flavonoid biosynthesis of and anthocyanin accumulation. A significant positive correlation between FtUFGT8 and FtUFGT15 expression and anthocyanin accumulation capacity was observed in the tartary buckwheat seedlings after cold stress. Overexpression in Arabidopsis thaliana showed that FtUFGT8, FtUFGT15, and FtUFGT41 significantly increased the anthocyanin content in transgenic plants. Unexpectedly, overexpression of FtUFGT6, while not leading to enhanced anthocyanin accumulation, significantly enhanced the growth yield of transgenic plants. When wild-type plants have only cotyledons, most of the transgenic plants of FtUFGT6 had grown true leaves. Moreover, the growth speed of the oxFtUFGT6 transgenic plant root was also significantly faster than that of the wild type. At later growth, FtUFGT6 transgenic plants showed larger leaves, earlier twitching times and more tillers than wild type, whereas FtUFGT15 showed opposite results. CONCLUSIONS: Seven FtUFGTs were isolated from tartary buckwheat. FtUFGT8, FtUFGT15, and FtUFGT41 can significantly increase the accumulation of total anthocyanins in transgenic plants. Furthermore, overexpression of FtUFGT6 increased the overall yield of Arabidopsis transgenic plants at all growth stages. However, FtUFGT15 shows the opposite trend at later growth stage and delays the growth speed of plants. These results suggested that the biological function of FtUFGT genes in tartary buckwheat is diverse.


Assuntos
Fagopyrum/genética , Genes de Plantas/genética , Glicosiltransferases/genética , Proteínas de Plantas/genética , Antocianinas/metabolismo , Arabidopsis/genética , Sequência Conservada , Fagopyrum/enzimologia , Flavonoides/metabolismo , Genes de Plantas/fisiologia , Glicosiltransferases/fisiologia , Filogenia , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Análise de Sequência de DNA
4.
J Agric Food Chem ; 67(37): 10521-10533, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31461284

RESUMO

This work was designed to comparatively investigate 27 dietary flavonoids that act as α-glucosidase inhibitors and insulin sensitizers. On the basis of the results of an in vitro experiment of α-glucosidase inhibition, myricetin (IC50 = 11.63 ± 0.36 µM) possessed the strongest inhibitory effect, followed by apigenin-7-O-glucoside (IC50 = 22.80 ± 0.24 µM) and fisetin (IC50 = 46.39 ± 0.34 µM). A three-dimensional quantitative structure-activity relationship model of α-glucosidase inhibitors with good predictive capability [comparative molecular field analysis, q2 = 0.529, optimum number of components (ONC) = 10, R2 = 0.996, F = 250.843, standard error of estimation (SEE) = 0.064, and two descriptors; comparative similarity index analysis, q2 = 0.515, ONC = 10, R2 = 0.997, F = 348.301, SEE = 0.054, and four descriptors] was established and indicated that meta positions of ring B favored bulky and minor, electron-withdrawing, and hydrogen bond donor groups. The presence of electron-donating and hydrogen bond acceptor groups at position 4' of ring B could improve α-glucosidase activity. Position 3 of ring C favored minor, electron-donating, and hydrogen bond donor groups, whereas position 7 of ring A favored bulky and hydrogen bond acceptor groups. Molecular docking screened five flavonoids (baicalein, isorhamnetin-3-O-rutinoside, apigenin-7-O-glucoside, kaempferol-7-O-ß-glucoside, and cyanidin-3-O-glucoside) that can act as insulin sensitizers and form strong combinations with four key protein targets involved in the insulin signaling pathway. Apigenin-7-O-glucoside (60 µM) can effectively improve insulin resistance, and glucose uptake increased by approximately 73.06% relative to the model group of insulin-resistant HepG2 cells. Therefore, apigenin-7-O-glucoside might serve as the most effective α-glucosidase inhibitor and insulin sensitizer. This work may guide diabetes patients to improve their condition through dietary therapy.


Assuntos
Flavonoides/química , Inibidores de Glicosídeo Hidrolases/química , Insulina/metabolismo , Flavonoides/metabolismo , Flavonoides/farmacologia , Inibidores de Glicosídeo Hidrolases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
5.
J Agric Food Chem ; 67(35): 9967-9978, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403784

RESUMO

Following the recent completion of the draft genome sequence of the tea plant, high-throughput decoding of gene function, especially for those involved in complex secondary metabolic pathways, has become a major challenge. Here, we profiled the metabolome and transcriptome of 11 tea cultivars, and then illustrated a weighted gene coexpression network analysis (WGCNA)-based system biological strategy to interpret metabolomic flux, predict gene functions, and mine key regulators involved in the flavonoid biosynthesis pathway. We constructed a multilayered regulatory network, which integrated the gene coexpression relationship with the microRNA target and promoter cis-regulatory element information. This allowed us to reveal new uncharacterized TFs (e.g., MADSs, WRKYs, and SBPs) and microRNAs (including 17 conserved and 15 novel microRNAs) that are potentially implicated in different steps of the catechin biosynthesis. Furthermore, we applied metabolic-signature-based association method to capture additional key regulators involved in catechin pathway. This provides important clues for the functional characterization of five SCPL1A acyltransferase family members, which might be implicated in the production balance of anthocyanins, galloylated catechins, and proanthocyanins. Application of an "omics"-based system biology strategy should facilitate germplasm utilization and provide valuable resources for tea quality improvement.


Assuntos
Camellia sinensis/metabolismo , Flavonoides/química , Redes Reguladoras de Genes , Camellia sinensis/química , Camellia sinensis/classificação , Camellia sinensis/genética , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Metabolômica , Folhas de Planta/química , Folhas de Planta/classificação , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
6.
J Agric Food Chem ; 67(32): 8819-8838, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31322880

RESUMO

Recent studies about hot-water extracts from sugar maple (Acer saccharum Marsh.) bark and buds demonstrated that they contain high amounts of phenolic structures that may be used as antioxidant food additives. However, the detailed chemical composition of these maple-derived extracts has yet to be determined. By performing high-performance liquid chromatography-diode array detector-high-resolution mass spectrometry (HPLC-DAD-HRMS)-based dereplication, we were able to spike and classify almost 100 metabolites in each hot-water extract. The sugar maple bark hot-water extract is rich in simple phenolic compounds and phenylpropanoid derivatives, while bud extract contains predominantly flavonoids, benzoic acids, and their complex derivatives (condensed and hydrolyzable tannins). Among those chemical structures, we tentatively identified 69 phenolic compounds potentially reported for the first time in the genus Acer. Considering the growing commercial demand in natural products, the phenolic fingerprints of sugar maple bark and bud hot-water extracts will help in promoting these two maple-derived products as new sources of bioactive compounds in the food, nutraceutical, and cosmetic industries.


Assuntos
Acer/química , Casca de Planta/química , Extratos Vegetais/química , Acer/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Espectrometria de Massas por Ionização por Electrospray
7.
J Photochem Photobiol B ; 197: 111550, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31330424

RESUMO

The plant species of the genus Epimedium L. are well-known traditional Chinese medicinal herbs with special therapeutic effects on human beings and animals in invigorating sexuality and strengthening muscles and bones. In large-scale cultivating Epimedium that is a typical shade plant species, they are arbitrarily covered with black colored shade nets. However, their optimal growth conditions, especially light, are still less understood. During the investigation of different light qualities on the growth of Epimedium pseudowushanense, it was found that, all the values of plant growth characteristics (except shoot number) and photosynthetic characteristics were lower under red, yellow, or blue light treatment than under white light treatment. However, yellow light treatment had beneficial effects on shoot number, dry biomass (per plant) as well as net photosynthesis rate (Pn) and maximal apparent quantum efficiency (AQY) in E. pseudowushanense when compared with red or blue light treatment. More importantly, we found that E. pseudowushanense accumulated higher levels of bioactive flavonoids under yellow light treatment than under white, red, or blue light treatment. Furthermore, both RNAseq and qPCR analyses revealed that yellow light could highly up-regulate the expression levels of flavonoid biosynthetic genes, in particular CHS1, F3H1, PT_5, and raGT_5 that possibly contributed to the enhanced accumulation of bioactive flavonoids in E. pseudowushanense. Taken together, our study revealed that yellow light is the optimal light for the growth of E. pseudowushanense. Our results provided key information on how to improve the cultivation condition and concurrently enhance the accumulation of bioactive flavonoids in E. pseudowushanense.


Assuntos
Epimedium/metabolismo , Flavonoides/metabolismo , Luz , Biomassa , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Epimedium/crescimento & desenvolvimento , Epimedium/efeitos da radiação , Flavonoides/análise , Fotossíntese/efeitos da radiação , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/metabolismo , Brotos de Planta/efeitos da radiação , RNA de Plantas/genética , RNA de Plantas/metabolismo , Análise de Sequência de RNA , Transcriptoma/efeitos da radiação
8.
Food Chem ; 299: 125110, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31284244

RESUMO

This study was undertaken in order to estimate the effect of in vitro propagation on antioxidant activity in strawberry. Results of this research exhibited differences between conventionally and in vitro propagated plants in respect of all traits analyzed. In spite of the decrease in range and mean content of vitamin C and polyphenols as well as antioxidant activity, the genetic gain expressed as percent of mean was higher in microplants regarding phenolics, flavonoids and antioxidant activity in contrast to conventional plants (22.39-20.83, 21.79-15.61, 9.52-3.39; resp.). Correlation and path coefficients showed changes of antioxidants inter-relations between micropropagated and conventional plants. Phenolics and vitamin C correlated positively with antioxidant activity in all genotypes. The highest positive direct effect on antioxidant activity was observed via vitamin C in microplants (0.705), while in conventional plants via phenolics (0.834). Flavonoids affected directly and positively antioxidant activity in microplants (0.103) and negatively in conventional plants (-0.143).


Assuntos
Antioxidantes/metabolismo , Flavonoides/metabolismo , Fragaria/crescimento & desenvolvimento , Fragaria/genética , Ácido Ascórbico/genética , Ácido Ascórbico/metabolismo , Flavonoides/genética , Fragaria/metabolismo , Genótipo , Fenóis/metabolismo , Polifenóis/genética , Polifenóis/metabolismo
9.
Life Sci ; 232: 116618, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265854

RESUMO

AIMS: Mitochondrial dysfunction has been regarded as one of the hallmarks of cerebral ischemia-reperfusion injury. In previous studies, we have provided evidence that the extracellular signaling pathway (ERK) 1/2 inhibitor PD98059 improved the neurological deficits by modulating antioxidant and anti-apoptotic activities in rats subjected to cardiac arrest/cardiopulmonary resuscitation (CA/CPR). Since oxidative stress can activate mitochondria-dependent apoptosis and autophagy, we further explored the effects of PD98059 on mitochondria involved with apoptosis and autophagy in rat CA model. MATERIALS AND METHODS: We disposed PD98059 in CA/CPR rats, tested the mitochondrial-mediated apoptosis pathway in brain tissues at 24 h post-resuscitation by mitochondrial permeability transition pores (MPTP), cytochrome c (CytC), BCL-2, BAX, caspase-3, as well as autophagy by LC3, Beclin-1, and p62. Furthermore, we explored the relationship of dynamin-related protein 1 (Drp1) with apoptosis and autophagy. KEY FINDINGS: Our study showed that PD98059 decreased the openings of MPTP, CytC release, caspase3 activation, apoptotic indices, LC3-II, Beclin-1and increased P62. PD98059 also inhibited mitochondria-dependent apoptosis and the activity of autophagy in a dose-dependent manner in rat cerebral cortices at 24 h post-resuscitation. The generation of phosphorylated Drp1-616 was down-regulated accompanied by a decrease of TUNEL-positive cells and LC3 in dual immunostaining after PD98059 inhibited activation of ERK signaling pathway in a dose-dependent manner in rat cerebral cortices at 24 h post-resuscitation. SIGNIFICANCE: PD98059 protects the brain against mitochondrial-mediated apoptosis and autophagy at 24 h post-resuscitation in rats subjected to CA/CPR, which is linked with the downregulation of Drp1 expression.


Assuntos
Flavonoides/farmacologia , Parada Cardíaca/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Reanimação Cardiopulmonar , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Flavonoides/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
10.
J Sci Food Agric ; 99(13): 6011-6019, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31216060

RESUMO

BACKGROUND: The growing area has a substantial effect on plants, affecting secondary metabolism. For hops, different authors have studied the effect of growing area on the chemical composition of cones with the aim of verifying and understanding the changes in hop characters. Despite the scant literature the subject receives increasing attention by brewers and hop growers. The present study aimed to characterize, using gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography with ultraviolet detection (HPLC-UV), cones of hop (Humulus lupulus L.) cultivar Cascade. Plant material was obtained from nine different areas of Italy and compared with Cascade samples grown in the United States, Germany and Slovenia. RESULTS: Differences in bitter acids and xanthohumol content were observed. Nevertheless, no correlation between bitter acids and xanthohumol production, on the one hand, and rainfall, temperatures and latitude, on the other hand, were observed in our samples. The Slovenia samples were richer in molecules that confer hoppy, woody and flower notes; USA2 samples were more characterized by woody, earthy, grassy and floral aroma, quite different characters if compared to USA1, which had the lowest presence of grassy aromatic compounds. In the Italian samples, TRENTINO was the genotype most characterized by limonene presence. CONCLUSION: The results of this study are indicative of the importance for hop users to know and characterize hops coming from different growing regions. The study pays special attention to the characterization of the differences in chemical characters of Cascade hop in Italy, where hop cultivation has developed only recently, but is in continuous expansion. © 2019 Society of Chemical Industry.


Assuntos
Humulus/química , Humulus/crescimento & desenvolvimento , Extratos Vegetais/análise , Ácidos/análise , Ácidos/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Itália , Odorantes/análise , Extratos Vegetais/metabolismo , Propiofenonas/análise , Propiofenonas/metabolismo , Metabolismo Secundário , Paladar
11.
J Agric Food Chem ; 67(25): 7016-7024, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31194907

RESUMO

Most of the previous in vitro digestion treatments were conducted directly to whole grains without extraction of free phenolics, thus the bioaccessible phenolics contained both free phenolics that survived the digestion and digested phenolics released by digestion. However, the profiles of digested phenolics released by digestion remain unknown. This study was designed to investigate the phytochemical contents, peroxyl radical scavenging capacities (PSCs), and cellular antioxidant activities (CAAs) of free, digested, and bound fractions of whole grains. Total phenolic contents of whole grains were highest in digested fraction, followed by free and bound fractions. The predominant phenolics were 12 phenolic acids and one flavonoid, which mostly existed in bound forms, then in digested and free forms. The digested phenolics bound to proteins were in conjugated form. The bound fractions had the highest PSCs, followed by free and digested fractions. CAAs were highest in bound fractions, followed by digested and free fractions.


Assuntos
Antioxidantes/metabolismo , Compostos Fitoquímicos/metabolismo , Extratos Vegetais/metabolismo , Grãos Integrais/metabolismo , Antioxidantes/química , Linhagem Celular , Digestão , Flavonoides/química , Flavonoides/metabolismo , Células Hep G2 , Humanos , Modelos Biológicos , Fenóis/química , Fenóis/metabolismo , Compostos Fitoquímicos/química , Extratos Vegetais/química , Sementes/química , Sementes/metabolismo
12.
BMC Plant Biol ; 19(1): 277, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234776

RESUMO

BACKGROUND: The Asia lotus (Nelumbo nucifera Gaertn.) is an ornamental aquatic plant with high economic value. Flower colour is an important ornamental trait, with much of N. nucifera breeding focusing on its yellow flowers. To explore the yellow flower colouration mechanism in N. nucifera, we analysed its pigment constituents and content, as well as gene expression in the flavonoid pathway, in two N. nucifera cultivars. RESULTS: We performed metabolomic and gene expression analyses in two N. nucifera cultivars with yellow and white flowers, Molinqiuse (MLQS) and Yeguangbei (YGB), respectively, at five stages of flower colouration. Based on phenotypic observation and metabolite analyses, the later stages of flower colouration (S3-S5) were determined to be key periods for differences between MLQS and YGB, with dihydroflavonols and flavonols differing significantly between cultivars. Dihydroquercetin, dihydrokaempferol, and isorhamnetin were significantly higher in MLQS than in YGB, whereas kaempferol was significantly higher in YGB. Most of the key homologous structural genes in the flavonoid pathway were significantly more active in MLQS than in YGB at stages S1-S4. CONCLUSION: In this study, we performed the first analyses of primary and secondary N. nucifera metabolites during flower colouration, and found that isorhamnetin and kaempferol shunting resulted in petal colour differences between MLQS and YGB. Based on our data integration analyses of key enzyme expression in the putative flavonoid pathways of the two N. nucifera cultivars, NnFLS gene substrate specificity and differential expression of NnOMTs may be related to petal colour differences between MLQS and YGB. These results will contribute to determining the mechanism of yellow flower colouration in N. nucifera, and will improve yellow petal colour breeding in lotus species.


Assuntos
Flavonoides/metabolismo , Flores/genética , Nelumbo/metabolismo , Pigmentação/genética , Perfilação da Expressão Gênica , Genes de Plantas , Quempferóis/metabolismo , Metaboloma , Metiltransferases/genética , Nelumbo/enzimologia , Nelumbo/genética , Quercetina/análogos & derivados , Quercetina/metabolismo , Especificidade da Espécie
13.
Plant Sci ; 285: 132-140, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203877

RESUMO

Xanthomonas campestris pv. campestris (Xcc)- responsive soluble and cell wall-bound hydroxycinnamic acids (HAs) and flavonoids accumulation in relation to hormonal changes in two Brassica napus cultivars contrasting disease susceptibility were interpreted with regard to the disease resistance. At 14-day post inoculation with Xcc, disease resistance in cv. Capitol was distinguished by an accumulation of specific (HAs) and flavonoids particularly in cell-wall bound form, and was characterized by higher endogenous jasmonic acid (JA) resulting in a decrease of JA-based balance with other hormones, as well as enhanced expression of JA signaling that was concurrently based on upregulation of PAP1 (production of anthocyanin pigment 1), MYB transcription factor, and phenylpropanoid biosynthetic genes. Fourier transform infrared spectra confirmed higher amounts of esterified phenolic acids in cv. Capitol. These results indicate that enhanced JA levels and signaling in resistant cultivar was associated with a higher accumulation of HAs and flavonoids, particularly in the cell wall-bound form, and vice versa in the susceptible cultivar (cv. Mosa) with enhanced SA-, ABA-, and CK- levels and signaling. Thus the JA-mediated phenolic metabolites accumulation is an important feature for the management and breeding program to develop disease-resistant B. napus cultivar.


Assuntos
Brassica napus/imunologia , Parede Celular/metabolismo , Ácidos Cumáricos/metabolismo , Ciclopentanos/metabolismo , Resistência à Doença , Oxilipinas/metabolismo , Fenóis/metabolismo , Reguladores de Crescimento de Planta/fisiologia , Xanthomonas campestris , Brassica napus/metabolismo , Brassica napus/microbiologia , Brassica napus/fisiologia , Parede Celular/fisiologia , Resistência à Doença/fisiologia , Suscetibilidade a Doenças/microbiologia , Suscetibilidade a Doenças/fisiopatologia , Flavonoides/metabolismo , Peroxidação de Lipídeos , Microscopia Eletrônica de Varredura , Peptídeo Hidrolases/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Planta/metabolismo , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo
14.
Photochem Photobiol Sci ; 18(7): 1685-1699, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31166333

RESUMO

The UVR8 photoreceptor in Arabidopsis thaliana is specific for ultraviolet-B (UV-B; 280-315 nm) radiation and its activation leads to a number of UV-B acclimation responses, including the accumulation of flavonoids. UVR8 participates in a signaling cascade involving COP1 and HY5 so that the absence of any of these components results in a reduction in the ability of a plant to accumulate flavonoids in response to UV; Cop1 mutants show high dropouts and hy5-ks50 hyh double mutants show very low levels of flavonoids. The predominant phenolics in Arabidopsis thaliana are sinapic acid derivatives as well as non-aclyated quercetin and kaempferol di- and triglycosides containing glucose and rhamnose as glycosylated sugar moieties. How this flavonoid profile in Arabidopsis thaliana is affected by UV radiation, how rapidly these changes occur in changing UV conditions, and which components of the UV-B signalling pathway are involved in rapid UV acclimatization reactions is poorly understood. In the present study, we examined these questions by characterizing the flavonoid profiles of Arabidopsis thaliana signalling mutants and wild types grown under different UV levels of constant UV-B+PAR ratios and then transferring a subset of plants to alternate UV conditions. Results indicate that flavonoid accumulation in Arabidopsis thaliana is triggered by UV and this response is amplified by higher levels of UV but not by all compounds to the same extent. The catechol structure in quercetin seems to be less important than the glycosylation pattern, e.g. having 2 rhamnose moieties in determining responsivity. At low UV+PAR intensities the introduction of UV leads to an initial tendency of increase of flavonoids in the wild types that was detected after 3 days. It took 7 days for these changes to be detected in plants grown under high UV+PAR intensities suggesting a priming of PAR. Thus, the flavonoid profile in Arabidopsis thaliana is altered over time following exposure to UV and PAR, but the functional significance of these changes is currently unclear.


Assuntos
Arabidopsis/efeitos da radiação , Flavonoides/metabolismo , Transdução de Sinais/efeitos da radiação , Raios Ultravioleta , Arabidopsis/química , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Cromatografia Líquida de Alta Pressão , Proteínas Cromossômicas não Histona/metabolismo , Flavonoides/análise , Mutagênese , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Espectrometria de Massas por Ionização por Electrospray , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
15.
BMC Plant Biol ; 19(1): 254, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195973

RESUMO

BACKGROUND: Asian citrus psyllid (ACP) is the primary vector responsible for the transmission of the phloem-limited bacteria Candidatus Liberibacter spp., associated with huanglongbing (HLB), which causes great loss to the citrus industry. Although the roles of leaf color and volatile compounds in the orientation of ACP have been proven, the quantification of color and allelochemicals in the host plant are kept unclear, especially in wild citrus germplasms. RESULTS: Chongyi wild mandarin significantly attracted more ACP than wild Hong Kong kumquat, 'Gannan zao' navel orange and orange jasmine did in the four-choice and olfactometer assays. The color parameters of the tender leaves from Chongyi wild mandarin and 'Gannan zao' were similar. The yellow color in both of them was less saturated than that of the other two plants species, but Chongyi wild mandarin had significant lower carotenoid content (P < 0.05). Notably metabolic profiling differences were observed among the healthy tender shoots from the four tested plants via UPLC-QQQ-MS and GC-MS analyses. Comparing with the other three plant species, 66 and 50 metabolites with significantly different contents in Chongyi wild mandarin were selected as UPLC-identified and GC-identified metabolites of interest (P < 0.05), respectively. Flavonoids accounted for a large group of secondary metabolites of interest, which may function as stimulants or repellents of ACP. Higher content of salicylic acid o-hexoside and lower content of (+)-jasmonic acid in Chongyi wild mandarin may lead to higher amount of methyl salicylate (an ACP attractant) and lower amount of trans-ocimene (an attractant to herbivores' natural enemies) as well as the suppression of JA-mediated wounding response. This kind of synergistic or antagonistic effect among the metabolites differentially accumulated in Chongyi wild mandarin made it a more attractive host plant to ACP. CONCLUSIONS: Less saturated yellow color, high amount of attractants, low amount of repellents and insensitivity of JA-mediated wounding response are the four possible reasons why Chongyi wild mandarin attracted more ACP. This work may shed light on the olfactory and visual response of ACP to wild citrus germplasm hosts, and suggest the feasibility of developing ACP attractants or repellents patterned on potential metabolites.


Assuntos
Hemípteros/fisiologia , Folhas de Planta/metabolismo , Rutaceae/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Citrus/metabolismo , Cor , Flavonoides/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos Voláteis/metabolismo
16.
Arch Endocrinol Metab ; 63(3): 241-249, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31166364

RESUMO

OBJECTIVE: To investigate the relationship of flavonoid intake during pregnancy with maternal excessive body weight and gestational diabetes mellitus (GDM). SUBJECTS AND METHODS: A cross-sectional study was conducted among 785 adult women in singleton pregnancies, and data were collected at the time of the oral glucose tolerance test. For the body mass index (BMI) classification according to the gestational age, the criteria of Atalah was used, and the diagnosis of GDM was based on the World Health Organization of 2014. Two 24-hour dietary recalls were obtained, and the usual intake was determined by the Multiple Source Method. Adjusted multinomial logistic regression was used to investigate the relationship of the flavonoids with overweight and obesity, and adjusted non-conditional logistic regression for the relationship of the flavonoids with GDM. RESULTS: The mean (SD) age of the women was 28 (5) years, 32.1% were overweight, 24.6% were obese and 17.7% were diagnosed with GDM. The median (P25, P75) of total flavonoid intake was 50 (31,75) mg/day. Considering the eutrophic women as the reference, the pregnant women with a higher total flavonoid intake [OR 0.62 (95% CI 0.38; 0.96)] and anthocyanidin intake [OR 0.62 (95% CI 0.40; 0.99)] were less likely to be obese when compared to the women with lower intakes. No association of the flavonoids intake with overweight or GDM was found. CONCLUSION: A very low intake of flavonoids was observed. The data suggest that the intake of foods naturally rich in total flavonoids and anthocyanidin has a beneficial role regarding obesity among pregnant women.


Assuntos
Diabetes Gestacional/metabolismo , Comportamento Alimentar , Flavonoides/administração & dosagem , Obesidade/metabolismo , Adulto , Estudos Transversais , Registros de Dieta , Feminino , Flavonoides/metabolismo , Teste de Tolerância a Glucose , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
17.
Planta ; 250(3): 857-871, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31203447

RESUMO

MAIN CONCLUSION: This represents the first report deciphering the dehydration response of suspension-cultured cells of a crop species, highlighting unique and shared pathways, and adaptive mechanisms via profiling of 330 metabolites. Grasspea, being a hardy legume, is an ideal model system to study stress tolerance mechanisms in plants. In this study, we investigated the dehydration-responsive metabolome in grasspea suspension-cultured cells (SCCs) to identify the unique and shared metabolites crucial in imparting dehydration tolerance. To reveal the dehydration-induced metabolite signatures, SCCs of grasspea were exposed to 10% PEG, followed by metabolomic profiling. Chromatographic separation by HPLC coupled with MRM-MS led to the identification of 330 metabolites, designated dehydration-responsive metabolites (DRMs), which belonged to 28 varied functional classes. The metabolome was found to be constituted by carboxylic acids (17%), amino acids (13.5%), flavonoids (10.9%) and plant growth regulators (10%), among others. Pathway enrichment analysis revealed predominance of metabolites involved in phytohormone biosynthesis, secondary metabolism and osmotic adjustment. Exogenous application of DRMs, arbutin and acetylcholine, displayed improved physiological status in stress-resilient grasspea as well as hypersensitive pea, while administration of lauric acid imparted detrimental effects. This represents the first report on stress-induced metabolomic landscape of a crop species via a suspension culture system, which would provide new insights into the molecular mechanism of stress responses and adaptation in crop species.


Assuntos
Lathyrus/metabolismo , Aminoácidos/metabolismo , Ácidos Carboxílicos/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Produtos Agrícolas/metabolismo , Desidratação , Flavonoides/metabolismo , Lathyrus/fisiologia , Redes e Vias Metabólicas/fisiologia , Metabolômica , Reguladores de Crescimento de Planta/metabolismo
18.
Aquat Toxicol ; 213: 105228, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31229888

RESUMO

The present work was conducted to study how restoration of perturbed oxidant and antioxidant homeostasis is achieved in the UV-C radiation exposed cells of cyanobacterium Nostoc muscorum Meg1. Exposure to varying doses of UV-C radiation (6, 12, 18 and 24 mJ/cm2) showed damage to ultrastructures especially cytoplasmic membrane, cell wall and organisation of thylakoid membranes of the cyanobacterium under transmission electron microscope (TEM). All doses of UV-C exposure significantly induced most of the enzymatic antioxidant {catalase, superoxide dismutase (SOD) and glutathione reductase (GR)} activities, their protein levels (western blot analysis) and mRNA levels (real time PCR analysis) within the first hour of post UV-C radiation incubation period. In the same way, contents of many non-enzymatic antioxidants such as ascorbic acid, reduced glutathione, proline, phenol and flavonoids were also augmented in response to such UV-C radiation exposure. Although notable increase in ROS level was only seen in cultures treated with 24 mJ/cm2 UV-C exposure which also registered increase in protein oxidation (22%) and lipid peroxidation (20%), this boost in both enzymatic and non-enzymatic antioxidants was significant in all radiation exposed cells indicating cell's preparation to combat rise in oxidants. Further, albeit all antioxidants increased considerably, their levels were restored back to control values by day seventh re-establishing physiological redox state for normal metabolic function. The combined efficiency of the enzymatic and non-enzymatic antioxidants were so effective that they were able to bring down the increase levels of ROS, lipid peroxidation and protein oxidation to the physiological levels within 1 h of radiation exposure signifying their importance in the defensive roles in protecting the organism from oxidative toxicity induced by UV-C radiation exposure.


Assuntos
Antioxidantes/metabolismo , Homeostase , Nostoc muscorum/fisiologia , Nostoc muscorum/efeitos da radiação , Oxidantes/metabolismo , Estresse Fisiológico/efeitos da radiação , Raios Ultravioleta , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Cisteína/metabolismo , Flavonoides/metabolismo , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Nostoc muscorum/ultraestrutura , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Prolina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade
19.
J Photochem Photobiol B ; 196: 111509, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31128431

RESUMO

Cnidium officinale Makino is an important medicinal plant of oriental clinics and is considered as the main source of phthalides, polyphenols, and flavonoids. However, there is no available report regarding the effect of different light colors on the secondary metabolites composition of C. officinale. In this study different light (dark, white, blue, red and red: blue) conditions were arranged to raise callus on MS medium containing 0.5 mg·L-1 of each 2,4-D and BAP. Callus grown in dark condition showed maximum (2.0 g) fresh weight with lower total phenolic and flavonoids contents. Also, in dark condition callus faced higher catalase (CAT) and guaiacol peroxidase (GPX) activities to avoid free radicals. Mix (red: blue) light condition favored the synthesis of phenolics and flavonoids in callus at the cost of higher ascorbate peroxidase (APX) and superoxide dismutase (SOD) enzymes expression. However, DPPH free radical scavenging activity was less variable among the samples from the different light conditions. Interestingly, the HPLC profile showed higher (28.3 µg·g-1 DW) phthalide accumulation in dark grown-cultures. Compared to other light conditions, 3-butyledinephthalide accumulation was higher (0.43 µg·g-1 DW) in white light-grown callus. These findings suggest that light conditions play an important role in the regulation of in vitro callus growth and synthesis of important medicinal compounds of C. officinale.


Assuntos
Antioxidantes/metabolismo , Cnidium/química , Flavonoides/metabolismo , Luz , Fenóis/metabolismo , Antioxidantes/química , Ascorbato Peroxidases/metabolismo , Benzofuranos/análise , Benzofuranos/metabolismo , Cromatografia Líquida de Alta Pressão , Cnidium/crescimento & desenvolvimento , Cnidium/metabolismo , Flavonoides/química , Fenóis/química , Células Vegetais/metabolismo , Células Vegetais/efeitos da radiação , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Superóxido Dismutase/metabolismo
20.
BMC Plant Biol ; 19(1): 203, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31096923

RESUMO

BACKGROUND: Brassica napus is of substantial economic value for vegetable oil, biofuel, and animal fodder production. The breeding of yellow-seeded B. napus to improve seed quality with higher oil content, improved oil and meal quality with fewer antinutrients merits attention. Screening the genes related to this phenotype is valuable for future rapeseed breeding. RESULTS: A total of 85,407 genes, including 4317 novel genes, were identified in the developing seeds of yellow- and black-seeded B. napus, and yellow rapeseed was shown to be an introgression line between black-seeded B. napus and yellow-seeded Sinapis alba. A total of 15,251 differentially expressed genes (DEGs) were identified among all the libraries, and 563 and 397 common DEGs were identified throughout black and yellow seed development, including 80 upregulated and 151 downregulated genes related to seed development and fatty acid accumulation. In addition, 11 up-DEGs and 31 down-DEGs were identified in all developmental stages of yellow rapeseed compared with black seed. Enrichment analysis revealed that many DEGs were involved in biosynthetic processes, pigment metabolism, and oxidation-reduction processes, such as flavonoid and phenylpropanoid biosynthesis, phenylalanine metabolism, flavone and flavonol biosynthesis, and fatty acid biosynthesis and metabolism. We found that more than 77 DEGs were related to flavonoid and lignin biosynthesis, including 4CL, C4H, and PAL, which participated in phenylalanine metabolism, and BAN, CHI/TT5, DFR, F3H, FLS, LDOX, PAP, CHS/TT4, TT5, bHLH/TT8, WD40, MYB, TCP, and CYP, which were involved in flavonoid biosynthesis. Most of these DEGs were downregulated in yellow rapeseed and were consistent with the decreased flavonoid and lignin contents. Both up- and down-DEGs related to fatty acid biosynthesis and metabolism were also analyzed, which could help to explain the improved oil content of yellow rapeseed. CONCLUSION: This research provided comprehensive transcriptome data for yellow-seeded B. napus with a unique genetic background, and all the DEGs in comparison with the black-seeded counterpart could help to explain seed quality differences, such as lower pigmentation and lignin contents, and higher oil content.


Assuntos
Brassica napus/genética , Sementes/genética , Brassica napus/crescimento & desenvolvimento , Ácidos Graxos/metabolismo , Flavonoides/metabolismo , Perfilação da Expressão Gênica , Genes de Plantas/genética , Genes de Plantas/fisiologia , Lignina/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sementes/crescimento & desenvolvimento , Análise de Sequência de DNA , Transcriptoma
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