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1.
Phys Chem Chem Phys ; 23(32): 17656-17662, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34373871

RESUMO

In this manuscript the ability of selenium carbohydrates to undergo chalcogen bonding (ChB) interactions with protein residues has been studied at the RI-MP2/def2-TZVP level of theory. An inspection of the Protein Data Bank (PDB) revealed SeA (A = O, C and S) intermolecular contacts involving Se-pyranose ligands and ASP, TYR, SER and MET residues. Theoretical models were built to analyse the strength and directionality of the interaction together with "Atoms in Molecules" (AIM), Natural Bonding Orbital (NBO) and Non Covalent Interactions plot (NCIplot) analyses, which further assisted in the characterization of the ChBs described herein. We expect that the results from this study will be useful to expand the current knowledge regarding biological ChBs as well as to increase the visibility of the interaction among the carbohydrate chemistry community.


Assuntos
Lectinas/metabolismo , Monossacarídeos/metabolismo , Compostos Organosselênicos/metabolismo , Agaricales/química , Aspergillus oryzae/química , Bases de Dados de Proteínas , Escherichia coli/química , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Ligação de Hidrogênio , Lectinas/química , Modelos Moleculares , Monossacarídeos/química , Compostos Organosselênicos/química , Ligação Proteica , Selênio/química , Eletricidade Estática , Termodinâmica
2.
BMC Plant Biol ; 21(1): 245, 2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34051740

RESUMO

BACKGROUND: Arabinogalactan-proteins (AGPs) are heavily glycosylated with type II arabinogalactan (AG) polysaccharides attached to hydroxyproline residues in their protein backbone. Type II AGs are necessary for plant growth and critically important for the establishment of normal cellular functions. Despite the importance of type II AGs in plant development, our understanding of the underlying role of these glycans/sugar residues in mucilage formation and seed coat epidermal cell development is poorly understood and far from complete. One such sugar residue is the glucuronic acid residues of AGPs that are transferred onto AGP glycans by the action of ß-glucuronosyltransferase genes/enzymes. RESULTS: Here, we have characterized two ß-glucuronosyltransferase genes, GLCAT14A and GLCAT14C, that are involved in the transfer of ß-glucuronic acid (GlcA) to type II AGs. Using a reverse genetics approach, we observed that glcat14a-1 mutants displayed subtle alterations in mucilage pectin homogalacturonan (HG) compared to wild type (WT), while glcat14a-1glcat14c-1 mutants displayed much more severe mucilage phenotypes, including loss of adherent mucilage and significant alterations in cellulose ray formation and seed coat morphology. Monosaccharide composition analysis showed significant alterations in the sugar amounts of glcat14a-1glcat14c-1 mutants relative to WT in the adherent and non-adherent seed mucilage. Also, a reduction in total mucilage content was observed in glcat14a-1glcat14c-1 mutants relative to WT. In addition, glcat14a-1glcat14c-1 mutants showed defects in pectin formation, calcium content and the degree of pectin methyl-esterification (DM) as well as reductions in crystalline cellulose content and seed size. CONCLUSIONS: These results raise important questions regarding cell wall polymer interactions and organization during mucilage formation. We propose that the enzymatic activities of GLCAT14A and GLCAT14C play partially redundant roles and are required for the organization of the mucilage matrix and seed size in Arabidopsis thaliana. This work brings us a step closer towards identifying potential gene targets for engineering plant cell walls for industrial applications.


Assuntos
Arabidopsis/enzimologia , Galactanos/metabolismo , Glucuronosiltransferase/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cálcio/metabolismo , Parede Celular/metabolismo , Celulose/metabolismo , Esterificação , Glucuronosiltransferase/genética , Monossacarídeos/metabolismo , Pectinas/metabolismo , Fenótipo , Polissacarídeos/metabolismo , Sementes/enzimologia , Sementes/genética
3.
Food Chem ; 343: 128549, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33189480

RESUMO

Whole grains and pulses are rich in nutrients but often avoided by individuals with gastrointestinal disorders, due to high levels of fermentable oligo-, di-, monosaccharides and polyols (FODMAPs). This study investigated the impact of malting as delivery-system for endogenous enzymes. Malts from barley and wheat (naturally high in fructans), lentils and chickpeas (high in galactooligosaccharides), oat and buckwheat (low in FODMAPs) were produced. While barley and wheat malts had slightly elevated fructan-levels, in oat malt 0.8 g/100 g DM fructans were de novo synthesized. In lentils and chickpeas galactooligosaccharides diminished by 80-90%. Buckwheat did not contain any FODMAPs commonly investigated, but fagopyritols which may have a similar physiological effect. Also fagopyritols were degraded. While malted pulses and buckwheat are directly suitable for low FODMAP applications, using the combined approach of malting and fermentation, malted cereals could contribute to high nutritional values of such products.


Assuntos
Dissacarídeos/metabolismo , Grão Comestível/metabolismo , Manipulação de Alimentos/métodos , Frutanos/metabolismo , Monossacarídeos/metabolismo , Oligossacarídeos/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cicer/crescimento & desenvolvimento , Cicer/metabolismo , Dissacarídeos/análise , Fagopyrum/crescimento & desenvolvimento , Fagopyrum/metabolismo , Frutanos/análise , Germinação , Lens (Planta)/crescimento & desenvolvimento , Lens (Planta)/metabolismo , Monossacarídeos/análise , Oligossacarídeos/análise , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
4.
Methods Mol Biol ; 2156: 255-268, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32607986

RESUMO

The cell wall has a crucial influence on the mechanical properties of plant cells. It therefore has a strong impact on the freezing behavior and very likely also the freezing tolerance of plants. However, not many studies have addressed the question how cell wall composition and structure impact plant freezing tolerance and cold acclimation. In this chapter, we describe a comprehensive workflow to extract total cell wall material from leaves of Arabidopsis thaliana and to separate this material into fractions enriched in crystalline cellulose, pectins, and hemicelluloses by sequential fractionation. We further describe methods for the analysis of chemical structure, monosaccharide composition, and cellulose and uronic acid contents in the total cell wall material and the fractions in response to cold acclimation. Structural properties of cell wall material are analyzed by attenuated total reflectance-Fourier-transform infrared spectrometry (ATR-FTIR) and monosaccharide composition by gas chromatography-mass spectrometry (GC-MS) after isolation of alditol acetate derivatives of the sugars.


Assuntos
Aclimatação , Parede Celular/metabolismo , Temperatura Baixa , Células Vegetais/metabolismo , Fenômenos Fisiológicos Vegetais , Arabidopsis/fisiologia , Celulose/metabolismo , Fracionamento Químico , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Monossacarídeos/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Álcoois Açúcares/metabolismo
5.
Gene ; 741: 144522, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32145329

RESUMO

Virus-induced gene silencing (VIGS) is a transient based reverse genetic tool used to elucidate the function of novel gene in N. benthamiana. In current study, 14 UDP-D-glucuronate 4-epimerase (GAE) family members were identified and their gene structure, phylogeny and expression pattern were analyzed. VIGS system was optimized for the functional characterization of NbGAE6 homologous genes in N. benthamiana. Whilst the GAE family is well-known for the interconversion of UDP-D-GlcA and UDP-D-GalA during pectin synthesis. Our results revealed that the downregulation of these genes significantly reduced the amount of GalA in the homogalacturunan which is the major component of pectin found in primary cell wall. Biphenyl assay and high performance liquid chromatography analysis (HPLC) depicted that the level of 'GalA' monosaccharide reduced to 40-51% in VIGS plants as compared to the wild type plants. Moreover, qRT-PCR also confirmed the downregulation of the NbGAE6 mRNA in VIGS plants. In all, this is the first comprehensive study of the optimization of VIGS system for the provision of rapid silencing of GAE family members in N. benthamiana, eliminating the need of stable transformants.


Assuntos
Proteínas de Arabidopsis/genética , Carboidratos Epimerases/genética , Parede Celular/metabolismo , Nicotiana/genética , Pectinas/genética , Arabidopsis/genética , Parede Celular/genética , Parede Celular/virologia , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Vetores Genéticos/genética , Monossacarídeos/metabolismo , Pectinas/biossíntese , Peptídeos , Vírus de Plantas/genética , RNA Mensageiro/genética , Nicotiana/virologia
6.
Phytomedicine ; 55: 255-263, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668437

RESUMO

BACKGROUND: We previously showed that 3-O-ß-D-glucopyranosyl-(3R)-hydroxybutanolide (kinsenoside), a major compound of Anoectochilus formosanus, increased lipolysis through an AMP-activated protein kinase (AMPK)-dependent pathway. PURPOSE: To extend our previous finding, we investigated the in vivo and in vitro effects of kinsenoside on lipolysis and the involvement of cyclic AMP (cAMP)-dependent protein kinase A (PKA) and AMPK in kinsenoside-mediated lipolysis. STUDY DESIGN/METHODS: Mice were fed a high-fat diet for six weeks to induce lipid deposition and then treated with 50 and 100  mg/kg kinsenoside for two weeks. The coordination of PKA and AMPK activation in lipolysis in C3H10T1/2 adipocytes was evaluated in vitro by using PKA and AMPK's corresponding inhibitors, oil-red O staining, a glycerol production assay, and Western blot analysis. RESULTS: Kinsenoside reduced body weight, fat pad mass, and hepatic lipid accumulation in obese mice, and concurrently increased the induction and activation of hormone-sensitive lipase (HSL), perilipin, adipose triglyceride lipase (ATGL), and carnitine palmitoyltransferase I (CPT1). Kinsenoside concentration-dependently increased PKA activation by increasing the phosphorylation of Ser/Thr-PKA substrates in vitro. These increases were accompanied by a reduction in fat accumulation. Using H89 and Rp-8-Br-cAMPs to inhibit PKA reduced the release of glycerol but did not alter the activation of peroxisome proliferator-activated receptor alpha or the expression of CPT1 or ATGL. By contrast, compound C, an AMPK inhibitor, inhibited CPT1 and ATGL expression in kinsenoside-treated C3H10T1/2 adipocytes. In addition, H89 caused the reactivation of AMPK downstream targets by increasing the levels of the active form of pAMPK-Thr172, suggesting that PKA negatively modulates AMPK activity. CONCLUSION: Kinsenoside increased HSL activation through PKA-mediated phosphorylation at Ser660/563 and concomitantly increased perilipin activation in lipolysis. These lipolytic effects of kinsenoside were validated using 6-Bnz-cAMPs, a PKA agonist. In this study, we demonstrated that in addition to AMPK, PKA also plays a crucial role in kinsenoside-mediated lipolysis.


Assuntos
4-Butirolactona/análogos & derivados , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Lipólise/efeitos dos fármacos , Monossacarídeos/metabolismo , Extratos Vegetais/metabolismo , Esterol Esterase/metabolismo , 4-Butirolactona/metabolismo , Animais , Masculino , Camundongos , Orchidaceae/química , Extratos Vegetais/química
7.
Sci Rep ; 8(1): 14297, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250238

RESUMO

Non-alcoholic fatty liver disease (NAFLD) has emerged as a public health concern as reflected in its widespread distribution in the general population. Yet, treatment options are scarce which is at least in part due to lack of reliable human in vitro disease models. Here, we report a human hepatic 3D spheroid system cultured under defined chemical conditions that has the potential to mimic steatotic conditions in a reversible manner, useful for identification of novel drug treatment conditions. Primary human hepatocytes (PHH) from different donors were cultured as spheroid microtissues in physiological in vivo -like culture conditions. Hepatic steatosis was induced over the course of three weeks in culture by supplementing the culture medium with pathophysiological concentrations of free fatty acids, carbohydrates and insulin. Effects of steatosis in the 3D system were evaluated on transcriptional, metabolomic and lipidomic levels. Free fatty acids on one hand as well as a combination of insulin and monosaccharides, promoted lipid accumulation in hepatocytes and increased expression of lipogenic genes, such as fatty acid synthase. This milieu also promoted development of insulin resistance within 2 weeks as manifested by an increase in gluconeogenic and insulin resistance markers, which are observed in type 2 diabetes mellitus and metabolic syndrome. Induced steatosis was reversible after withdrawal of lipogenic substrates and a further reduction in cellular fat content was observed following treatment with different antisteatotic compounds, such as metformin, glucagon, olaparib and antioxidants. Taken together, these results demonstrate that the 3D hepatic spheroids can serve as a valuable, HTS compatible model for the study of liver steatosis and facilitate translational discovery of novel drug targets.


Assuntos
Fígado Gorduroso/patologia , Resistência à Insulina , Fígado/patologia , Modelos Biológicos , Esferoides Celulares/patologia , Adulto , Células Cultivadas , Ácidos Graxos/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Insulina/metabolismo , Insulina/farmacologia , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/metabolismo , Masculino , Metabolômica , Pessoa de Meia-Idade , Monossacarídeos/metabolismo , Esferoides Celulares/metabolismo , Xenobióticos/metabolismo , Adulto Jovem
8.
Diabetes Care ; 41(8): 1732-1739, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29844096

RESUMO

OBJECTIVE: Nonalcoholic fatty liver disease (i.e., increased intrahepatic triglyceride [IHTG] content), predisposes to type 2 diabetes and cardiovascular disease. Adipose tissue lipolysis and hepatic de novo lipogenesis (DNL) are the main pathways contributing to IHTG. We hypothesized that dietary macronutrient composition influences the pathways, mediators, and magnitude of weight gain-induced changes in IHTG. RESEARCH DESIGN AND METHODS: We overfed 38 overweight subjects (age 48 ± 2 years, BMI 31 ± 1 kg/m2, liver fat 4.7 ± 0.9%) 1,000 extra kcal/day of saturated (SAT) or unsaturated (UNSAT) fat or simple sugars (CARB) for 3 weeks. We measured IHTG (1H-MRS), pathways contributing to IHTG (lipolysis ([2H5]glycerol) and DNL (2H2O) basally and during euglycemic hyperinsulinemia), insulin resistance, endotoxemia, plasma ceramides, and adipose tissue gene expression at 0 and 3 weeks. RESULTS: Overfeeding SAT increased IHTG more (+55%) than UNSAT (+15%, P < 0.05). CARB increased IHTG (+33%) by stimulating DNL (+98%). SAT significantly increased while UNSAT decreased lipolysis. SAT induced insulin resistance and endotoxemia and significantly increased multiple plasma ceramides. The diets had distinct effects on adipose tissue gene expression. CONCLUSIONS: Macronutrient composition of excess energy influences pathways of IHTG: CARB increases DNL, while SAT increases and UNSAT decreases lipolysis. SAT induced the greatest increase in IHTG, insulin resistance, and harmful ceramides. Decreased intakes of SAT could be beneficial in reducing IHTG and the associated risk of diabetes.


Assuntos
Gorduras Insaturadas na Dieta/efeitos adversos , Ácidos Graxos/efeitos adversos , Comportamento Alimentar/fisiologia , Fígado/metabolismo , Monossacarídeos/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/etiologia , Tecido Adiposo/metabolismo , Adulto , Metabolismo dos Carboidratos/fisiologia , Gorduras Insaturadas na Dieta/metabolismo , Ácidos Graxos/metabolismo , Feminino , Humanos , Insulina/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos/fisiologia , Masculino , Pessoa de Meia-Idade , Monossacarídeos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sobrepeso/complicações , Sobrepeso/metabolismo , Triglicerídeos/sangue , Aumento de Peso
9.
Plant Cell Physiol ; 59(4): 857-870, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29444327

RESUMO

Glycosylation mediated by UDP-dependent glycosyltransferase (UGT) is one of the most common reactions for the biosynthesis of small molecule glycosides. As glycosides have various biological roles, we characterized UGT genes from grapevine (Vitis vinifera). In silico analysis of VvUGT genes that were highly expressed in leaves identified UGT92G6 which showed sequence similarity to both monosaccharide and disaccharide glucoside-forming transferases. The recombinant UGT92G6 glucosylated phenolics, among them caffeic acid, carvacrol, eugenol and raspberry ketone, and also accepted geranyl glucoside and citronellyl glucoside. Thus, UGT92G6 formed mono- and diglucosides in vitro from distinct compounds. The enzyme specificity constant Vmax/Km ratios indicated that UGT92G6 exhibited the highest specificity towards caffeic acid, producing almost equal amounts of the 3- and 4-O-glucoside. Transient overexpression of UGT92G6 in Nicotiana benthamiana leaves confirmed the production of caffeoyl glucoside; however, the level of geranyl diglucoside was not elevated upon overexpression of UGT92G6, even after co-expression of genes encoding geraniol synthase and geraniol UGT to provide sufficient precursor. Comparative sequence and 3-D structure analysis identified a sequence motif characteristic for monoglucoside-forming UGTs in UGT92G6, suggesting an evolutionary link between mono- and disaccharide glycoside UGTs. Thus, UGT92G6 functions as a mono- and diglucosyltransferase in vitro, but acts as a caffeoyl glucoside UGT in N. benthamiana.


Assuntos
Dissacarídeos/metabolismo , Evolução Molecular , Glicosiltransferases/química , Glicosiltransferases/metabolismo , Monossacarídeos/metabolismo , Vitis/enzimologia , Ácidos Cafeicos/farmacologia , Cimenos , Ensaios Enzimáticos , Glucosídeos/farmacologia , Cinética , Metaboloma , Modelos Moleculares , Monoterpenos/farmacologia , Fenóis/metabolismo , Filogenia , Extratos Vegetais/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Especificidade por Substrato , Terpenos/farmacologia
10.
Int J Mol Sci ; 19(2)2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29415484

RESUMO

Zinc oxide (ZnO) nanoparticles (NPs) are widely used as a Zn supplement, because Zn plays a role in many cellular and immune functions but public concern about their potentially undesirable effects on the human body is growing. When NPs are added in food matrices, interactions between NPs and food components occur, which can affect biological systems. In this study, interactions between ZnO NPs and saccharides were investigated by measuring changes in hydrodynamic radius, zeta potential and solubility and by quantifying amounts of adsorbed saccharides on NPs; acacia honey, sugar mixtures (containing equivalent amounts of fructose, glucose, sucrose and maltose) and monosaccharide solutions were used as model compounds. Biological responses of NPs dispersed in different saccharides were also evaluated in human intestinal cells and rats in terms of cytotoxicity, cellular uptake, intestinal transport and oral absorption. The results demonstrate that the hydrodynamic radii and zeta potentials of NPs were highly affected by saccharides. In addition, trace nutrients influenced NP/saccharide interactions and interactive effects between saccharides on the interactions were found. NPs in all saccharides increased inhibition of cell proliferation and enhanced cellular uptake. Oral absorption of NPs was highly enhanced by 5% glucose, which is in-line with intestinal transport result. These findings show that ZnO NPs interact with saccharides and these interactions affects biological responses.


Assuntos
Nanopartículas Metálicas/química , Monossacarídeos/química , Óxido de Zinco/química , Animais , Transporte Biológico , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Hidrodinâmica , Mucosa Intestinal/metabolismo , Nanopartículas Metálicas/ultraestrutura , Monossacarídeos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Solubilidade , Óxido de Zinco/metabolismo , Óxido de Zinco/farmacocinética
11.
J Med Food ; 21(7): 633-640, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29328869

RESUMO

Inflammatory bowel diseases (IBDs) are mainly represented by ulcerative colitis and Crohn's disease, and the increase in the incidence tends to follow the rapid industrialization and lifestyle of modern societies. FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) consist of molecules that are poorly absorbed in the small intestine and are fermented by bacteria in the colon leading to symptoms such as bloating, flatulence, diarrhea, and abdominal pain. Reduction of the ingestion of FODMAP could reduce the symptoms and improve the quality of life. This review aimed to summarize some important aspects of IBD and evaluate the effects of this diet on this inflammatory condition. Studies including the term FODMAP (and similar terms) and IBD were selected for this review (MEDLINE database was used PubMed/PMC). A low FODMAP diet may be an effective tool to the management of the common abdominal symptoms in patients with functional gastrointestinal symptoms once these molecules trigger these symptoms. This diet may also reduce the expression of pro-inflammatory markers such as C-reactive protein and fecal calprotectin and may interfere with the microbiome and its metabolites. The use of a low FODMAP diet can bring benefits to the IBD patients, but may also modify their nutritional status. Thus it should be utilized in appropriated conditions, and dietary supplements should be necessary to avoid deficiencies that could be caused by a low FODMAP diet over long periods. We suggest that further investigations are required to elucidate when and how to apply the FODMAP diet in IBD patients.


Assuntos
Dissacarídeos/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Monossacarídeos/metabolismo , Oligossacarídeos/metabolismo , Polímeros/metabolismo , Animais , Bactérias/metabolismo , Citocinas/metabolismo , Humanos , Doenças Inflamatórias Intestinais/dietoterapia , Doenças Inflamatórias Intestinais/microbiologia
12.
Plant Dis ; 102(7): 1434-1444, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30673559

RESUMO

Effects of monosaccharide-amended soils on suppression of Rhizoctonia damping-off of sugar beet were compared under controlled experiments. Suppressive effects of glucose, fructose, sorbose, and xylose were significantly (P < 0.001) greater than that of galactose or mannose but the effect of sorbose was reduced by soil treatments with antibiotics. Saprotrophic growth of Rhizoctonia solani in the laimosphere also was suppressed by glucose, fructose, sorbose, and xylose, whereas only sorbose repressed pericarp colonization. Sugar alcohols (mannitol, sorbitol, and xylitol) neither suppressed Rhizoctonia damping-off nor halted the saprotrophic growth of the pathogen. Seed germination was not affected by any of these six monosaccharides, whereas galactose and mannose inhibited seedling emergence significantly (P < 0.001) compared with the nontreated control or other monosaccharides. Soil fertilization with inorganic nitrogen at a C/N ratio of 20:1 negated the suppressive effects of glucose and fructose on both damping-off and saprotrophic colonization but improved seedling growth in carbonized soils. Obviously, microbial competition for mineral nitrogen was responsible for disease suppression; however, it delayed seedling growth after emergence. This paradox was resolved by adding glucose to the top 1-cm surface-soil zone at a C/N ratio of 50:1 or 125:1. This protected the laimosphere, resulting in effective disease suppression while complementarily enhancing seedling growth.


Assuntos
Beta vulgaris/microbiologia , Carbono/metabolismo , Monossacarídeos/metabolismo , Nitrogênio/metabolismo , Doenças das Plantas/microbiologia , Rhizoctonia/fisiologia , Solo/química , Antibacterianos/farmacologia , Recuperação e Remediação Ambiental/métodos , Frutose/metabolismo , Frutose/farmacologia , Glucose/metabolismo , Glucose/farmacologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Monossacarídeos/farmacologia , Doenças das Plantas/prevenção & controle , Plântula/microbiologia , Microbiologia do Solo , Xilose/metabolismo , Xilose/farmacologia
13.
J Agric Food Chem ; 65(50): 11073-11084, 2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29205038

RESUMO

Virgin rapeseed (Brassica napus) oil is a valuable niche product, if delivered with a high quality. In this study, the effects of moist storage of B. napus seeds for 1 to 4 days on the seed metabolome and the chemo-sensory properties of the produced oils were determined. The concentrations of several primary metabolites, including monosaccharides and amino acids, rapidly increased in the seeds, probably indicating the breakdown of storage compounds to support seed germination. Seed concentrations of indole glucosinolates increased with a slight time offset suggesting that amino acids may be used to modify secondary metabolism. The volatile profiles of the oils were pronouncedly influenced by moist seed storage, with the sensory quality of the oils decreasing. This study provides a direct time-resolved link between seed metabolism under moist conditions and the quality of the resulting oils, thereby emphasizing the crucial role of dry seed storage in ensuring high oil quality.


Assuntos
Brassica napus/química , Óleos de Plantas/química , Sementes/metabolismo , Água/análise , Aminoácidos/análise , Aminoácidos/metabolismo , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Armazenamento de Alimentos , Humanos , Monossacarídeos/análise , Monossacarídeos/metabolismo , Óleos de Plantas/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Paladar , Água/metabolismo
14.
Glycoconj J ; 34(5): 585-590, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28676909

RESUMO

This article presents a new insight about TBY-2 cells; from extracellular polysaccharides secretion to cell wall composition during cell suspension culture. In the medium of cells taken 2 days after dilution (end of lag phase), a two unit pH decrease from 5.38 to 3.45 was observed and linked to a high uronic acid (UA) amount secretion (47.8%) while, in 4 and 7 day-old spent media, pH increased and UA amounts decreased 35.6 and 42.3% UA, respectively. To attain deeper knowledge of the putative link between extracellular polysaccharide excretion and cell wall composition, we determined cell wall UA and neutral sugar composition of cells from D2 to D12 cultures. While cell walls from D2 and D3 cells contained a large amount of uronic acid (twice as much as the other analysed cell walls), similar amounts of neutral sugar were detected in cells from lag to end of exponential phase cells suggesting an enriched pectin network in young cultures. Indeed, monosaccharide composition analysis leads to an estimated percentage of pectins of 56% for D3 cell wall against 45% D7 cell walls indicating that the cells at the mid-exponential growth phase re-organized their cell wall linked to a decrease in secreted UA that finally led to a stabilization of the spent medium pH to 5.4. In conclusion, TBY-2 cell suspension from lag to stationary phase showed cell wall remodeling that could be of interest in drug interaction and internalization study.


Assuntos
Parede Celular/química , Nicotiana/metabolismo , Células Vegetais/química , Polissacarídeos/isolamento & purificação , Ácidos Urônicos/isolamento & purificação , Técnicas de Cultura de Células , Parede Celular/metabolismo , Células Cultivadas , Concentração de Íons de Hidrogênio , Monossacarídeos/isolamento & purificação , Monossacarídeos/metabolismo , Pectinas/isolamento & purificação , Pectinas/metabolismo , Células Vegetais/metabolismo , Polissacarídeos/metabolismo , Nicotiana/citologia , Nicotiana/crescimento & desenvolvimento , Ácidos Urônicos/metabolismo
15.
BMC Plant Biol ; 17(1): 86, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28486974

RESUMO

BACKGROUND: Unlike in abscission or dehiscence, fruit of kiwifruit Actinidia eriantha develop the ability for peel detachment when they are ripe and soft in the absence of a morphologically identifiable abscission zone. Two closely-related genotypes with contrasting detachment behaviour have been identified. The 'good-peeling' genotype has detachment with clean debonding of cells, and a peel tissue that does not tear. The 'poor-peeling' genotype has poor detachability, with cells that rupture upon debonding, and peel tissue that fragments easily. RESULTS: Structural studies indicated that peel detachability in both genotypes occurred in the outer pericarp beneath the hypodermis. Immunolabelling showed differences in methylesterification of pectin, where the interface of labelling coincided with the location of detachment in the good-peeling genotype, whereas in the poor-peeling genotype, no such interface existed. This zone of difference in methylesterification was enhanced by differential cell wall changes between the peel and outer pericarp tissue. Although both genotypes expressed two polygalacturonase genes, no enzyme activity was detected in the good-peeling genotype, suggesting limited pectin breakdown, keeping cell walls strong without tearing or fragmentation of the peel and flesh upon detachment. Differences in location and amounts of wall-stiffening galactan in the peel of the good-peeling genotype possibly contributed to this phenotype. Hemicellulose-acting transglycosylases were more active in the good-peeling genotype, suggesting an influence on peel flexibility by remodelling their substrates during development of detachability. High xyloglucanase activity in the peel of the good-peeling genotype may contribute by having a strengthening effect on the cellulose-xyloglucan network. CONCLUSIONS: In fruit of A. eriantha, peel detachability is due to the establishment of a zone of discontinuity created by differential cell wall changes in peel and outer pericarp tissues that lead to changes in mechanical properties of the peel. During ripening, the peel becomes flexible and the cells continue to adhere strongly to each other, preventing breakage, whereas the underlying outer pericarp loses cell wall strength as softening proceeds. Together these results reveal a novel and interesting mechanism for enabling cell separation.


Assuntos
Actinidia/fisiologia , Actinidia/citologia , Actinidia/enzimologia , Actinidia/genética , Parede Celular/fisiologia , Esterificação , Frutas/fisiologia , Galactanos/metabolismo , Expressão Gênica , Genes de Plantas , Genótipo , Metilação , Monossacarídeos/metabolismo , Pectinas/metabolismo , Células Vegetais/fisiologia , Polissacarídeos/metabolismo
16.
Plant Cell Environ ; 40(9): 1834-1848, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28556250

RESUMO

Nitric oxide (NO) is extensively involved in various growth processes and stress responses in plants; however, the regulatory mechanism of NO-modulated cellular sugar metabolism is still largely unknown. Here, we report that NO significantly inhibited monosaccharide catabolism by modulating sugar metabolic enzymes through S-nitrosylation (mainly by oxidizing dihydrolipoamide, a cofactor of pyruvate dehydrogenase). These S-nitrosylation modifications led to a decrease in cellular glycolysis enzymes and ATP synthase activities as well as declines in the content of acetyl coenzyme A, ATP, ADP-glucose and UDP-glucose, which eventually caused polysaccharide-biosynthesis inhibition and monosaccharide accumulation. Plant developmental defects that were caused by high levels of NO included delayed flowering time, retarded root growth and reduced starch granule formation. These phenotypic defects could be mediated by sucrose supplementation, suggesting an essential role of NO-sugar cross-talks in plant growth and development. Our findings suggest that molecular manipulations could be used to improve fruit and vegetable sweetness.


Assuntos
Arabidopsis/metabolismo , Monossacarídeos/metabolismo , Óxido Nítrico/farmacologia , Complexos de ATP Sintetase/metabolismo , Adenosina Difosfato Glucose/metabolismo , Trifosfato de Adenosina/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/enzimologia , Glicólise/efeitos dos fármacos , Mutação/genética , Nitrosação , Oxirredução , Fenótipo , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Solubilidade , Amido/metabolismo , Sacarose/farmacologia , Ácido Tióctico/análogos & derivados , Ácido Tióctico/metabolismo , Uridina Difosfato Glucose/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-28129552

RESUMO

Zizyphi Spinosi Semen (ZSS) has a long history of sedative-hypnotic use in China. As a novel flavone C-glycoside, coumaroylspinosin is a main flavonoid only found in ZSS. Up to now, its pharmacokinetic information and tissue distribution in vivo are not available yet. With a simple, rapid and sensitive HPLC-MS/MS method, the pharmacokinetics and tissue distribution of coumaroylspinosin were investigated in Sprague-Dawley (SD) rats after its intravenous administration. Puerarin was used as the internal standard (IS). The samples were extracted by a simple protein precipitation method with methanol. The MS analysis was performed with multiple reaction monitoring (MRM), and the transitions were set at m/z 753.3→427.0 for coumaroylspinosin and m/z 415.3→295.3 for IS, respectively. The method was successfully applied for investigating the pharmacokinetics and tissue distribution of coumaroylspinosin in Sprague Dawley (SD) rats after tail vein injection with 4.0mg/kg of the flavonoid. The calibration curves covered over the range of 0.02-10µg/mL in plasma and various tissues samples with good linearity(r≥0.9956). The lower limit of quantification (LLOQ) in all samples was less than 20ng/mL. The intra- and inter-day precisions were below 15% and accuracy was from -3.78% to 4.68%. No significant matrix effect was observed, and the average extraction recovery was acceptable. Coumaroylspinosin could be cleared quickly from the rat plasma with the half-life (t1/2) of 1.86±0.15h. It was distribute widely in vivo, and the main tissue depots of coumaroylspinosin in rats were found to be intestine, muscle and lung. With the method, the pharmacokinetic parameters and tissue distribution of coumaroylspinosin in SD rats were investigated for the first time. The results demonstrated that coumaroylspinosin was distributed widely and rapidly in various rat tissues after intravenous administration.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Flavonoides/análise , Flavonoides/metabolismo , Monossacarídeos/análise , Monossacarídeos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Distribuição Tecidual , Ziziphus/química
18.
Appl Biochem Biotechnol ; 181(2): 638-649, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27613615

RESUMO

Cytokinins are phytohormones that play multiple roles to control plant growth and development. In this study, leaf biomass and the production of andrographolide compounds in a medicinal plant Andrographis paniculata were significantly increased after exogenously treating with the synthetic cytokinin cytokinin-1-(2-chloro-4-pyridyl)-3-phenylurea (CPPU) at 0 (water), 5, or 10 mg L-1 and observed the results for 24 h, 48 h, and 7 days of treatment. It was found that CPPU could significantly enhance new axillary bud formation and further promote branching 4.6-5.6-fold higher, resulting in higher fresh weight (FW) and dry weight (DW) than the control. Application of CPPU at 5 mg L-1 significantly promoted the highest contents of total reducing sugar at 2.5-fold in leaves and at 1.5-fold in roots. Although treatments of CPPU significantly affected the increasing contents of chlorophyll and carotenoid (1.2-1.6-fold), CPPU at 10 mg L-1 slightly caused leaf stress and chlorophyll reduction. Interestingly, 5 mg L-1 CPPU could enhance andrographolide content, an active anti-infectious compound in Andrographis paniculata (2.2-fold higher than the control) that reached the highest content at 24 h after treatment. This study suggested that CPPU should be suitable for field application to promote leaf yields and induce the production of useful pharmaceutical compounds in Andrographis paniculata.


Assuntos
Andrographis/fisiologia , Diterpenos/metabolismo , Monossacarídeos/metabolismo , Compostos de Fenilureia/administração & dosagem , Folhas de Planta/fisiologia , Citocininas/administração & dosagem , Relação Dose-Resposta a Droga , Oxirredução/efeitos dos fármacos , Estatística como Assunto
19.
Bioresour Technol ; 224: 590-600, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27810249

RESUMO

This study reports the profiling of volatile compounds generated during microwave-assisted chemical pre-treatment of sorghum leaves. Compounds including acetic acid (0-186.26ng/g SL), furfural (0-240.80ng/g SL), 5-hydroxymethylfurfural (HMF) (0-19.20ng/g SL) and phenol (0-7.76ng/g SL) were detected. The reducing sugar production was optimized. An intelligent model based on Artificial Neural Networks (ANNs) was developed and validated to predict a profile of 21 volatile compounds under novel pre-treatment conditions. This model gave R2-values of up to 0.93. Knowledge extraction revealed furfural and phenol exhibited high sensitivity to acid- and alkali concentration and S:L ratio, while phenol showed high sensitivity to microwave duration and intensity. Furthermore, furfural production was majorly dependent on acid concentration and fit a dosage-response relationship model with a 2.5% HCl threshold. Significant non-linearities were observed between pre-treatment conditions and the profile of various compounds. This tool reduces analytical costs through virtual analytical instrumentation, improving process economics.


Assuntos
Micro-Ondas , Folhas de Planta/química , Sorghum/química , Compostos Orgânicos Voláteis/análise , Resíduos/análise , Ácido Acético/análise , Furaldeído/análogos & derivados , Furaldeído/análise , Ácido Clorídrico/química , Modelos Teóricos , Monossacarídeos/metabolismo , Redes Neurais de Computação , Fenóis/química , Folhas de Planta/metabolismo , Sorghum/metabolismo , Compostos Orgânicos Voláteis/química , Gerenciamento de Resíduos/métodos
20.
Sci Rep ; 6: 38728, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27929093

RESUMO

Many cohort studies have shown that consumption of diets containing a higher composition of foods derived from plants reduces mortality from coronary heart disease (CHD). Here, we examined the active components of a plant-based diet and the underlying mechanisms that reduce the risk of CHD using three rat models and a quantitative proteomics approach. In a short-term myocardial infarction (MI) model, intake of wheat extract (WE), the representative cardioprotectant identified by screening approximately 4,000 samples, reduced myocardial injury by inhibiting apoptosis, enhancing ATP production, and maintaining protein homeostasis. In long-term post-MI models, this myocardial protection resulted in ameliorating adverse left-ventricular remodelling, which is a predictor of heart failure. Among the wheat components, arabinose and xylose were identified as active components responsible for the observed efficacy of WE, which was administered via ingestion and tail-vein injections. Finally, the food components of plant-based diets that contained cell wall polysaccharides rich in arabinose, xylose, and possibly fucose were found to confer protection against myocardial injury. These results show for the first time that specific monosaccharides found in the cell wall polysaccharides in plant-based diets can act as active ingredients that reduce CHD by inhibiting postocclusion steps, including MI and heart failure.


Assuntos
Parede Celular/metabolismo , Dieta , Modelos Animais de Doenças , Monossacarídeos/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Extratos Vegetais/administração & dosagem , Polissacarídeos/metabolismo , Triticum/química , Animais , Apoptose , Masculino , Traumatismo por Reperfusão Miocárdica/patologia , Proteômica , Ratos , Ratos Sprague-Dawley , Remodelação Ventricular
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