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1.
Appl Biochem Biotechnol ; 191(1): 444-462, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32248370

RESUMO

Lignocellulose biomass contain large macromolecules especially cellulose and hemicelluloses that can be converted to fuel and chemicals using microbial biocatalysts. This study presents comprehensive optimization of production of biomass-hydrolyzing enzymes (BHE) by a high ß-glucosidase-producing Trichoderma SG2 for bioconversion of lignocellulose biomass. Overall, a mixture of paper powder and switchgrass was most suited for production of BHE in submerged fermentation (SmF). BHE production was significantly different for various organic and inorganic nitrogen sources. The combination of peptone, yeast extract, and ammonium sulfate resulted in the highest activities (Units/mL) of BHE: 9.85 ± 0.55 cellulase, 38.91 ± 0.31 xylanase, 21.19 ± 1.35 ß-glucosidase, and 7.63 ± 0.31 ß-xylosidase. Surfactants comparably enhanced BHE production. The highest cellulase activity (4.86 ± 0.55) was at 25 °C, whereas 35 °C supported the highest activities of xylanase, ß-glucosidase, and ß-xylosidase. A broad initial culture pH (4-7) supported BHE production. The Topt for cellulase and xylanase was 50 °C. ß-xylosidase and ß-glucosidase were optimally active at 40 and 70 °C, respectively; pH 5 resulted in highest cellulase, ß-glucosidase, and ß-xylosidase activities; and pH 6 resulted in highest xylanase activity. Response surface methodology (RSM) was used to optimize major medium ingredients. BHE activities were several orders of magnitude higher in solid-state fermentation (SSF) than in SmF. Therefore, SSF can be deployed for one-step production of complete mixture of Trichoderma SG2 BHE for bioconversion of biomass to saccharide feedstock.


Assuntos
Biocatálise , Biomassa , Celulose , Proteínas Fúngicas/metabolismo , Glucosidases/metabolismo , Polissacarídeos , Trichoderma/crescimento & desenvolvimento , Celulose/química , Celulose/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo
2.
J Sci Food Agric ; 100(5): 2110-2120, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31875958

RESUMO

BACKGROUND: Anthocyanins and flavonols play a significant role in contributing to wine color and mouthfeel, and the interaction of malolactic fermentation with these compounds is not well known. Here we investigated the adsorption of these compounds by Oenococcus oeni and Lactobacillus plantarum. RESULTS: Delphinidin-3-glucoside (D3G) was adsorbed the most, followed by malvidin-3-glucoside (M3G) and peonidin-3-glucoside (P3G) for both the bacterial species, while flavonols were not adsorbed. An increase in ß-glycosidase activity suggested that this enzyme breaks down the anthocyanin glucosides, providing sugars for growth. An average decline of approximately 65% in enzyme activity in the presence of substantial residual sugar was observed. The specific metabolic rates were found to be dependent on the class of anthocyanin and species / strain of the bacteria. Selective adsorption of anthocyanins and not the flavonol glycosides suggest that electrostatic interactions mediate the adsorption. Further, a breakdown of anthocyanins resulted in phloroglucinol aldehyde from the flavonoid A-ring and corresponding phenolic acids from the B-ring, i.e., gallic acid for D3G, syringic acid for M3G, and vanillic acid for P3G. CONCLUSIONS: The breakdown and adsorption of the anthocyanin glucosides can help explain the color loss and aroma changes, such as the appearance of syringic and vanillic acid, associated with malolactic fermentation. © 2019 Society of Chemical Industry.


Assuntos
Antocianinas/análise , Glucosídeos/análise , Glicosídeos/análise , Lactobacillus plantarum/metabolismo , Oenococcus/metabolismo , Quercetina/análise , Vinho/microbiologia , Adsorção , Biotransformação , Fermentação , Flavonoides , Manipulação de Alimentos , Microbiologia de Alimentos , Glucosidases/metabolismo , Vinho/análise
3.
Food Chem ; 305: 125462, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31618694

RESUMO

The objectives of this research were to demonstrate the changes in isoflavone-aglycones, total phenolics, and biological properties (digestive enzyme inhibition; antioxidant) from six organs including leaves, leafstalks, roots, stems, seeds, and pods at different growth times of soybean plant. Three isoflavone-aglycones in microwave-assisted acid hydrolysis extracts were elucidated using UHPLC-ESI-Q-TOF-MS/MS and their contents exhibited remarkable differences in leaves (245.93-2239.33 µg/g), roots (854.96-4425.34 µg/g), and seeds (ND-2339.62 µg/g). Specifically, the collected samples on 15-Oct (leaves: 2239.33; seeds: 2339.62 µg/g) and 31-Aug (roots: 4425.34 µg/g) showed the highest isoflavone-aglycones, and daidzein was observed the most abundant component, comprising approximately 70%. Moreover, the inhibitions against α-glucosidase and α-amylase displayed the predominant effects in roots (89;91%) and leaves (81;85%) of samples on 31-Aug and 15-Oct at 300 µg/ml. The antioxidant activities on ABTS, DPPH, and hydroxyl radicals increased considerably with the increases of growth times in leaves and seeds, especially, ABTS showed the highest scavenging abilities: leaves (15-Oct;83%) > roots (31-Aug;75%) > seeds (15-Oct;68%). Therefore, our results suggest that soybean leaves, roots and seeds may be considered as excellent natural sources for nutraceuticals.


Assuntos
Antioxidantes/química , Glucosidases/metabolismo , Isoflavonas/análise , Micro-Ondas , Soja/química , Cromatografia Líquida de Alta Pressão , Glucosidases/antagonistas & inibidores , Hidrólise , Isoflavonas/metabolismo , Fenóis/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Sementes/química , Sementes/metabolismo , Soja/crescimento & desenvolvimento , Soja/metabolismo , Espectrometria de Massas em Tandem/métodos
4.
Mol Biol Rep ; 47(2): 935-942, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31741259

RESUMO

Phytophthora is considered one of the most destructive genus for many agricultural plant species worldwide, with a strong environmental and economic impact. Phytophthora cinnamomi is a highly aggressive Phytophthora species associated with the forest decline and responsible for the ink disease in chestnut trees (Castanea sativa Miller), a culture which is extremely important in Europe. This pathogenicity occurs due to the action of several enzymes like the hydrolysis of 1,3-ß-glucans at specific sites by the enzyme endo-1,3-ß-D-glucosidase. The aim of this work to analyze the heterologous expression in two microorganisms, Escherichia coli and Pichia pastoris, of an endo-1,3-ß-D-glucosidase encoded by the gene ENDO1 (AM259651) from P. cinnamomi. Different plasmids were used to clone the gene on each organism and the real-time quantitative polymerase chain reaction was used to determine its level of expression. Homologous expression was also analyzed during growth in different carbon sources (glucose, cellulose, and sawdust) and time-course experiments were used for endo-1,3-ß-D-glucosidase production. The highest expression of the endo-1,3-ß-D-glucosidase gene occurred in glucose after 8 h of induction. In vivo infection of C. sativa by P. cinnamomi revealed an increase in endo-1,3-ß-D-glucosidase expression after 12 h. At 24 h its expression decreased and at 48 h there was again a slight increase in expression, and more experiments in order to further explain this fact are underway.


Assuntos
Glucana Endo-1,3-beta-D-Glucosidase/genética , Phytophthora/genética , Clonagem Molecular/métodos , Glucana 1,3-beta-Glucosidase/genética , Glucana Endo-1,3-beta-D-Glucosidase/metabolismo , Glucosidases/genética , Glucosidases/metabolismo , Phytophthora/metabolismo , Doenças das Plantas , Reação em Cadeia da Polimerase em Tempo Real/métodos
5.
Environ Pollut ; 255(Pt 2): 113321, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31610515

RESUMO

Ionic liquids (ILs) are extensively used in several chemistry fields. And research about the effects of ILs on soil microbes is needed. In this study, brown soil was exposed to 1-butyl-3-methylimidazolium bromide ([C4mim]Br), 1-hexyl-3-methylimidazolium bromide ([C6mim]Br) and 1-decyl-3-methylimidazolium bromide ([C10mim]Br). The toxicities of the three ILs are evaluated by measuring the soil culturable microbial number, enzyme activity, microbial diversity and, abundance of the ammonia monooxygenase (amoA) genes of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Results showed that all tested ILs caused a decrease in culturable microbial abundance. Tested ILs exposure inhibit urease activity and promote acid phosphatase and ß-glucosidase activities. Tested ILs reduced soil microbial diversity and the abundances of AOB-amoA and AOA-amoA genes significantly. After a comparison of the integrated biomarker response (IBR) index, the toxicities of tested ILs to soil microorganisms were as follows: [C10mim]Br > [C6mim]Br > [C4mim]Br. Among all collected biomarkers, the abundance of the AOA-amoA gene was the most sensitive one and was easily affected after ILs exposure.


Assuntos
Archaea/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Boratos/toxicidade , Brometos/toxicidade , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Fosfatase Ácida/metabolismo , Amônia/metabolismo , Glucosidases/metabolismo , Oxirredução , Oxirredutases/genética , Filogenia , Solo/química , Microbiologia do Solo , Urease/antagonistas & inibidores
6.
Nat Commun ; 10(1): 3185, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320625

RESUMO

Unfolded protein response (UPR) is an adaptive mechanism that aims at restoring ER homeostasis under severe environmental stress. Malignant cells are resistant to environmental stress, which is largely due to an activated UPR. However, the molecular mechanisms by which different UPR branches are selectively controlled in tumor cells are not clearly understood. Here, we provide evidence that PRKCSH, previously known as glucosidase II beta subunit, functions as a regulator for selective activation of the IRE1α branch of UPR. PRKCSH boosts ER stress-mediated autophosphorylation and oligomerization of IRE1α through mutual interaction. PRKCSH contributes to the induction of tumor-promoting factors and to tumor resistance to ER stress. Increased levels of PRKCSH in various tumor tissues are positively correlated with the expression of XBP1-target genes. Taken together, our data provide a molecular rationale for selective activation of the IRE1α branch in tumors and adaptation of tumor cells to severe environmental stress.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Transformação Celular Neoplásica/patologia , Estresse do Retículo Endoplasmático/fisiologia , Endorribonucleases/metabolismo , Glucosidases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Resposta a Proteínas não Dobradas/fisiologia , Animais , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Endorribonucleases/genética , Glucosidases/genética , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/patologia , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Transdução de Sinais/genética
7.
Food Chem ; 297: 125018, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253265

RESUMO

Different Ohmic heating conditions (OH, 10, 100, and 1000 Hz at 25 V; 45, 60, and 80 V at 60 Hz) were assessed to manufacture whey-raspberry flavored beverages. The inhibition of α-glucosidase, α-amylase, and angiotensin-converting I enzymes, antioxidant capacity, fatty acid profile, and volatile organic compounds (VOCs) were determined. OH treated samples presented lower anthocyanins content than the conventional treatment (2.91 ±â€¯0.23 mg/g), while the mild-intermediate conditions (10,100-Hz at 25 V and 45,60-V at 60 Hz) presented the highest chemical antioxidant activity when compared to the extreme processing conditions (1000 Hz-25 V and 80 V-60 Hz). OH led to an increase of 10% in both α-glucosidase (>99%) and α-amylase (≥70%). Among the VOCs, furfural and 5-hydroxymethylfurfural, a major intermediate Maillard reaction product was found in all treatments. Overall, OH can be used in the processing of whey-flavored raspberry beverages.


Assuntos
Bebidas/análise , Aromatizantes/química , Rubus/química , Soro do Leite/química , Antocianinas/análise , Antioxidantes/química , Culinária , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Glucosidases/antagonistas & inibidores , Glucosidases/metabolismo , Ondas de Rádio , Temperatura , Compostos Orgânicos Voláteis/análise , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
8.
Carbohydr Res ; 480: 42-53, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31174176

RESUMO

Sulfolobus solfataricus ß-glycosidase (SS-ßGly) belongs to Glycosyl Hydrolase family1 (GH1) with broad substrate specificity. SS-ßGly catalyzes both hydrolysis and transglycosylation reactions. SS-ßGly is commonly used to synthesize variety of galacto-oligosaccharides. A comparison of SS-ßGly with bacterial and eukaryotic homologs, using DALI search, revealed unique inserts. Free enzyme molecular dynamics (MD) simulation was performed under two different pH conditions (pH 6.5 and 2.5) at a constant temperature of 65 °C using GROMACS. A probable active-site loop (residues 331-364) in SS-ßGly was identified. Dynamics of substrate binding cavity revealed that it was buried and inaccessible during most timeframes at pH 6.5 whereas open and accessible at pH 2.5. New cavities identified during both simulations may act as probable water channel or product egress path. Analyses of docked complexes of 3D structures obtained at every 1ns interval with compounds, involved in hydrolysis and tranglycosylation reactions, demonstrated that conformational states sampled by SS-ßGly during free enzyme dynamics mimic the stages in enzyme catalysis thereby providing a mechanistic perspective. Current study revealed that conformational changes were conducive for hydrolysis at pH 6.5 and multiple cycles of transglycosylation at pH 2.5. Probable role of salt-bridge interactions in determining the type of reaction mechanism was also explored.


Assuntos
Biocatálise , Glucosidases/química , Glucosidases/metabolismo , Simulação de Dinâmica Molecular , Sequência de Aminoácidos , Domínio Catalítico , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Especificidade por Substrato
9.
Nat Commun ; 10(1): 2222, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31110237

RESUMO

Substrates associate and products dissociate from enzyme catalytic sites rapidly, which hampers investigations of their trajectories. The high-resolution structure of the native Hordeum exo-hydrolase HvExoI isolated from seedlings reveals that non-covalently trapped glucose forms a stable enzyme-product complex. Here, we report that the alkyl ß-D-glucoside and methyl 6-thio-ß-gentiobioside substrate analogues perfused in crystalline HvExoI bind across the catalytic site after they displace glucose, while methyl 2-thio-ß-sophoroside attaches nearby. Structural analyses and multi-scale molecular modelling of nanoscale reactant movements in HvExoI reveal that upon productive binding of incoming substrates, the glucose product modifies its binding patterns and evokes the formation of a transient lateral cavity, which serves as a conduit for glucose departure to allow for the next catalytic round. This path enables substrate-product assisted processive catalysis through multiple hydrolytic events without HvExoI losing contact with oligo- or polymeric substrates. We anticipate that such enzyme plasticity could be prevalent among exo-hydrolases.


Assuntos
Domínio Catalítico , Glucosidases/metabolismo , Modelos Moleculares , Proteínas de Plantas/metabolismo , Biocatálise , Cristalografia por Raios X , Ensaios Enzimáticos/métodos , Glucosidases/química , Glucosidases/isolamento & purificação , Glicosídeos/metabolismo , Hordeum/metabolismo , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Plântula/metabolismo , Especificidade por Substrato
10.
Adipocyte ; 8(1): 190-200, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31037987

RESUMO

Long-term weight loss maintenance is a problem of overweight and obesity. Changes of gene expression during weight loss (WL) by calorie restriction (CR) are linked to the risk of weight regain (WR). However, detailed information on genes/proteins involved in the mechanism is still lacking. Therefore, we developed an in-vitro model system for glucose restriction (GR) and refeeding (RF) to uncover proteome differences between GR with RF vs normal feeding, of which we explored the relation with WR after WL. Human Simpson-Golabi-Behmel Syndrome cells were subjected to changing levels of glucose to mimic the condition of CR and RF. Proteome profiling was performed by liquid chromatography tandem mass spectrometry. This in-vitro model revealed 44 proteins differentially expressed after GR and RF versus feeding including proteins of the focal adhesions. Four proteins showed a persistent up- or down-regulation: liver carboxylesterase (CES1), mitochondrial superoxide dismutase [Mn] (SOD2), alpha-crystallin B-chain (CRYAB), alpha-enolase (ENO1). In-vivo weight loss-induced RNA expression changes linked CES1, CRYAB and ENO1 to WR. Moreover, of these 44 proteins, CES1 and glucosidase II alpha subunit (GANAB) during follow up correlated with WR. Correlation clustering of in-vivo protein expression data indicated an interaction of these proteins with structural components of the focal adhesions and cytoplasmic filaments in the adipocytes.


Assuntos
Adipócitos/metabolismo , Biomarcadores Tumorais/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glucose/deficiência , Glucosidases/metabolismo , Fosfopiruvato Hidratase/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ganho de Peso , Cadeia B de alfa-Cristalina/metabolismo , Adipócitos/citologia , Biomarcadores Tumorais/genética , Hidrolases de Éster Carboxílico/genética , Células Cultivadas , Proteínas de Ligação a DNA/genética , Glucose/metabolismo , Glucosidases/genética , Humanos , Fosfopiruvato Hidratase/genética , Proteínas Supressoras de Tumor/genética , Cadeia B de alfa-Cristalina/genética
11.
J Microbiol Biotechnol ; 29(4): 562-570, 2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-30955258

RESUMO

ß-Glucosylglycerol (ß-GG) and their derivatives have potential applications in food, cosmetics and the healthcare industry, including antitumor medications. In this study, ß-GG and its unnatural glycosides were synthesized through the transglycosylation of two enzymes, Sulfolobus shibatae ß-glycosidase (SSG) and Deinococcus geothermalis amylosucrase (DGAS). SSG catalyzed a transglycosylation reaction with glycerol as an acceptor and cellobiose as a donor to produce 56% of ß-GGs [ß-D-glucopyranosyl-(1→1/3)-D-glycerol and ß-D-glucopyranosyl- (1→2)-D-glycerol]. In the second transglycosylation reaction, ß-D-glucopyranosyl-(1 → 1/3)-Dglycerol was used as acceptor molecules of the DGAS reaction. As a result, 61% of α-Dglucopyranosyl-( 1→4)-ß-D-glucopyranosyl-(1→1/3)-D-glycerol and 28% of α-D-maltopyranosyl- (1→4)-ß-D-glucopyranosyl-(1→1/3)-D-glycerol were synthesized as unnatural glucosylglycerols. In conclusion, the combined enzymatic synthesis of the unnatural glycosides of ß-GG was established. The synthesis of these unnatural glycosides may provide an opportunity to discover new applications in the biotechnological industry.


Assuntos
Glucosídeos/biossíntese , Glucosiltransferases/metabolismo , Glicosídeo Hidrolases/metabolismo , Glicosídeos/biossíntese , Biotecnologia , Celobiose/metabolismo , Deinococcus/enzimologia , Deinococcus/genética , Escherichia coli/genética , Glucosidases/metabolismo , Glucosídeos/análise , Glucosídeos/química , Glucosiltransferases/genética , Glicerol/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeos/análise , Glicosídeos/química
12.
Physiol Plant ; 166(1): 105-119, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30834537

RESUMO

The maximum quantum yield of photosystem II (as reflected by variable to maximum chlorophyll a fluorescence, Fv /Fm ) is regarded as one of the most important photosynthetic parameters. The genetic basis underlying natural variation in Fv /Fm , which shows low level of variations in plants under non-stress conditions, is not easy to be exploited using the conventional gene cloning approaches. Thus, in order to answer this question, we have followed another strategy: we used genome-wide association study (GWAS) and transgenic analysis in a rice mini-core collection. We report here that four single-nucleotide polymorphisms, located in the promoter region of ß-glucosidase 5 (BGlu-5), are associated with observed variation in Fv /Fm . Indeed, our transgenic analysis showed a good correlation between BGlu-5 and Fv /Fm . Thus, our work demonstrates the feasibility of using GWAS to study natural variation in Fv /Fm , suggesting that cis-element polymorphism, affecting the BGlu-5 expression level, may, indirectly, contribute to Fv /Fm variation in rice through the gibberellin signaling pathway. Further research is needed to understand the mechanism of our novel observation.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Glucosidases/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Celulases/genética , Celulases/metabolismo , Giberelinas/metabolismo , Glucosidases/genética , Complexo de Proteína do Fotossistema II/genética , Polimorfismo de Nucleotídeo Único/genética
13.
Molecules ; 24(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682802

RESUMO

Desert soil is one of the most severe conditions which negatively affect the environment and crop growth production in arid land. The application of organic amendments with inorganic fertilizers is an economically viable and environmentally comprehensive method to develop sustainable agriculture. The aim of this study was to assess whether milk tea waste (TW) amendment combined with chemical fertilizer (F) application can be used to improve the biochemical properties of sandy soil and wheat growth. The treatments included control without amendment (T1), chemical fertilizers (T2), TW 2.5% + F (T3), TW 5% + F (T4) and TW 10% + F (T5). The results showed that the highest chlorophyll (a and b) and carotenoids, shoot and root dry biomass, and leaf area index (LAI) were significantly (p < 0.05) improved with all amendment treatments. However, the highest root total length, root surface area, root volume and diameter were recorded for T4 among all treatments. The greater uptake of N, P, and K contents for T4 increased for the shoot by 68.9, 58.3, and 57.1%, and for the root by 65.7, 34.3, and 47.4% compared to the control, respectively. Compared with the control, T5 treatment decreased the soil pH significantly (p < 0.05) and increased soil enzyme activities such as urease (95.2%), ß-glucosidase (81.6%) and dehydrogenase (97.2%), followed by T4, T3, and T2. Our findings suggested that the integrated use of milk tea waste and chemical fertilizers is a suitable amendment method for improving the growth and soil fertility status of sandy soils.


Assuntos
Fertilizantes/análise , Leite/química , Solo/química , Resíduos Sólidos , Chá/química , Triticum/crescimento & desenvolvimento , Agricultura , Animais , Biomassa , Carotenoides/metabolismo , Clorofila/metabolismo , Glucosidases/metabolismo , Nitrogênio/química , Nutrientes/química , Oxirredutases/metabolismo , Fósforo/química , Potássio/química , Urease/metabolismo
14.
Int J Mol Sci ; 20(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678336

RESUMO

Four novel acylglycosides flavones (AGFs) including two quercetin acylglycosides and two kaempferol acylglycosides were isolated from Fuzhuan brick tea (FBT) as follows: quercetin 3-O-[α-l-rhamnopyranosyl (1→3)] [2-O''-(E)-p-coumaroyl] [ß-d-glucopyranosyl (1→3)-α-l-rhamnopyranosyl (1→6)]-ß-d-galactoside was named as camelliquercetiside E (1), quercetin 3-O-[α-l-rhamnopyranosyl (1→3)] [2-O''-(E)-p-coumaroyl] [α-l-rhamnopyranosyl (1→6)]-ß-d-galactoside was named as camelliquercetiside F (2), kaempferol 3-O-[α-l-arabinopyranosyl (1→3)] [2-O''-(E)-p-coumaroyl] [ß-d-glucopyranosyl (1→3)-α-l-rhamnopyranosyl (1→6)]-ß-d-glucoside was named as camellikaempferoside D (3), kaempferol 3-O-[α-l-arabinopyranosyl (1→3)] [2-O''-(E)-p-coumaroyl] [α-l-rhamnopyranosyl (1→6)]-ß-d-glucoside was named as camellikaempferoside E (4). Chemical structures of AGFs were identified by time-of-flight mass (TOF-MS) and NMR spectrometers (¹H NMR, 13C NMR, ¹H-¹H COSY, HMBC and HSQC), and the MS² fragmentation pathway of AGFs was further investigated. The inhibitory abilities of AGFs and their proposed metabolites on α-glucosidase and HMG-CoA reductase were analyzed by molecular docking simulation, and the results suggested that inhibitory activities of AGFs were significantly affected by acyl structure, number of glycosyl and conformation, and part of them had strong inhibitory activities on α-glucosidase and HMG-CoA reductase, suggesting that AGFs and their metabolites might be important ingredients that participate in the regulation of hypoglycemic and hypolipidemic effects. The results provided new AGFs and research directions for the practical study of FBT health functions in future.


Assuntos
Quempferóis/farmacologia , Simulação de Acoplamento Molecular , Quercetina/farmacologia , Chá/química , Acil Coenzima A/química , Acil Coenzima A/metabolismo , Camellia sinensis/química , Glucosidases/química , Glucosidases/metabolismo , Glicosídeos/química , Humanos , Quempferóis/química , Ligação Proteica , Quercetina/análogos & derivados
15.
Food Chem ; 274: 543-546, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30372976

RESUMO

Apiosidases are glycosidases relevant for aroma development during fermentation of wines and black tea. Reaction mechanism of apiosidase from Aspergillus aculeatus in commercial glycanase Viscozyme L was studied by 1H NMR technique. Study of hydrolysis of 4-nitrophenyl ß-D-apiofuranoside revealed that this reaction proceeds with inversion of hydroxyl group in the anomeric center, which confirms inverting mechanism of the enzyme and its inability to catalyze transapiosylation in syntheses of apiosides.


Assuntos
Aspergillus/enzimologia , Glucosidases/metabolismo , Fermentação , Glicosídeos/metabolismo , Hidrólise
16.
FEMS Microbiol Ecol ; 94(12)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299466

RESUMO

Seasonal changes of microbial abundance and associated extracellular enzymatic activity in marine snow and in seawater were studied in the northern Adriatic during a three-year period. Marine snow was present during the entire period of investigation, although in higher concentrations during summer than during winter. Microorganisms densely colonized marine snow and aggregate-associated enzymatic activity was substantially higher (up to 105 times) than in seawater. Alkaline phosphatase activity (APA) and aminopeptidase activity in marine snow showed seasonal variations with higher values in late spring-summer than in autumn-winter, probably in response to changes in the quantity and quality of organic matter. The highest cell-specific bacterial activity was found for phosphatase, followed by peptidase, and the lowest was for glucosidases. Differential hydrolysis of marine snow-derived organic matter points to the well-known phosphorus limitation of the northern Adriatic and indicates preferential utilization of phosphorus- and nitrogen-rich organic compounds by microbes, while hydrolysis of polysaccharides seemed to be less important. In oligotrophic conditions during summer, organic matter released from marine snow might represent a significant source of substrate for free-living bacteria in seawater. For the first time microorganisms producing APA in marine snow were identified, revealing that dense populations of bacteria expressed APA, while cyanobacteria did not. Cyanobacteria proliferating in marine snow could benefit from phosphorus release by bacteria and nanoflagellates.


Assuntos
Bactérias/crescimento & desenvolvimento , Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia , Neve/microbiologia , Fosfatase Alcalina/metabolismo , Aminopeptidases/metabolismo , Bactérias/classificação , Glucosidases/metabolismo , Microbiota , Fósforo , Estações do Ano
17.
Food Microbiol ; 76: 382-389, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30166164

RESUMO

Genes with the potential to code for enzymes involved in phenolic compound metabolism were detected in the genome of Lactobacillus pentosus IG1, isolated from a green olive fermentation. Based on homology, these genes could code for a 6-P-ß Glucosidase, two different Tannases, a Gallate decarboxylase and a p-Coumaric decarboxylase. Expression of up to seven of these genes was studied in L. pentosus IG1 (olive fermentation) and CECT4023T (corn silage), including responses upon exposure to relevant phenolic compounds and different olive extracts. Genes potentially coding Tannase, Gallate decarboxylase and p-Coumaric acid decarboxylase significatively increased their expression upon exposure to such compounds and extracts, although it was strain dependent. In general, both the genetic organization and the characteristics of gene expression resembled very much those described for Lactobacillus plantarum. In accordance to the observed induced gene expression, metabolism of specific phenolic compounds was achieved by L. pentosus. Thus, methyl gallate, gallic acid and the hydroxycinamic acids p-coumaric, caffeic and ferulic were metabolized. In addition, the amount of phenolics such as tyrosol, oleuropein, rutin and verbascoside included in a minimal culture medium was noticeably reduced, again dependent on the strain considered.


Assuntos
Proteínas de Bactérias/genética , Lactobacillus pentosus/genética , Lactobacillus pentosus/metabolismo , Olea/microbiologia , Fenóis/metabolismo , Proteínas de Bactérias/metabolismo , Carboxiliases/genética , Carboxiliases/metabolismo , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Fermentação , Ácido Gálico/análogos & derivados , Ácido Gálico/metabolismo , Glucosidases/genética , Glucosidases/metabolismo , Lactobacillus pentosus/enzimologia , Olea/química , Olea/metabolismo
18.
Stem Cell Res ; 32: 8-16, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30149291

RESUMO

Fibro-adipogenic progenitors (FAPs) are resident mesenchymal progenitors in adult skeletal muscle that support muscle repair, but also give rise to fibrous and adipose infiltration in response to disease and chronic injury. FAPs are identified using cell surface markers that do not distinguish between quiescent FAPs and FAPs actively engaged in the regenerative process. We have shown previously that FAPs are derived from cells that express the transcription factor Osr1 during development. Here we show that adult FAPs express Osr1 at low levels and frequency, however upon acute injury FAPs reactivate Osr1 expression in the injured tissue. Osr1+ FAPs are enriched in proliferating and apoptotic cells demonstrating that Osr1 identifies activated FAPs. In vivo genetic lineage tracing shows that Osr1+ activated FAPs return to the resident FAP pool after regeneration as well as contribute to adipocytes after glycerol-induced fatty degeneration. In conclusion, reporter LacZ or eGFP-CreERt2 expression from the endogenous Osr1 locus serves as marker for FACS isolation and tamoxifen-induced manipulation of activated FAPs.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Músculo Esquelético/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/fisiologia , Proteínas de Ligação ao Cálcio , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Cistos , Citometria de Fluxo , Edição de Genes , Regulação da Expressão Gênica , Glucosidases/genética , Glucosidases/metabolismo , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Hepatopatias , Músculo Esquelético/citologia , Fatores de Transcrição
19.
Bioorg Med Chem ; 26(13): 3731-3762, 2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-30017112

RESUMO

Hybrid drugs featuring two or more potentially bioactive pharmacophores have been recognized as advanced and superior chemical entities to simultaneously modulate multiple drug targets of multifactorial diseases, thus overcoming the severe side effects associated with a single drug molecule. The selection of these chemical moieties to produce hybrid structures with druggable properties is generally facilitated by the observed and/or anticipated synergistic pharmacological activities of the individual molecules. In this perspective, coumarin template has extensively been studied in pursuit of structurally diverse leads for drug development due to high affinity and specificity to different molecular targets. This review highlights the most commonly exploited approaches conceptualizing the design and construction of hybrid molecules by coupling two or more individual fragments with or without an appropriate linker. In addition to the design strategies, this review also summarizes and reflects on the therapeutic potential of these hybrid molecules for diverse enzyme inhibitory action as well as their observed structure-activity relationship (SAR). Several key features of the synthesized hybrid structures that assert a profound impact on the inhibitory function have also been discussed alongside computational investigations, inhibitor molecular diversity and selectivity toward multiple drug targets. Finally, these drug discovery and development efforts should serve as a handy reference aiming to provide a useful platform for the exploration of new coumarin-based compounds with enhanced enzyme inhibitory profile.


Assuntos
Cumarínicos/química , Desenho de Fármacos , Enzimas/metabolismo , Aldeído Redutase/antagonistas & inibidores , Aldeído Redutase/metabolismo , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/metabolismo , Colinesterases/química , Colinesterases/metabolismo , Cumarínicos/metabolismo , Enzimas/química , Glucosidases/antagonistas & inibidores , Glucosidases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Monoaminoxidase/química , Monoaminoxidase/metabolismo
20.
Bioorg Med Chem Lett ; 28(14): 2555-2560, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29866516

RESUMO

Stereoselective and efficient synthesis of hydroxymethyl-substituted rac-quercitols (13-15) was achieved, starting from cis-furan (Kobayashi, 2008) with photooxygenation reaction, which is readily available by the reduction of cis-phtalic anhydride. α- and ß-Glucosidase enzyme activity of the target molecules was evaluated and good inhibitor activity was seen. One- and two-dimensional NMR spectroscopy, IR spectroscopy and X-ray crystallography were utilized in the structure characterization of products.


Assuntos
Glucosidases/antagonistas & inibidores , Inibidores de Glicosídeo Hidrolases/farmacologia , Inositol/análogos & derivados , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Glucosidases/metabolismo , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Humanos , Inositol/síntese química , Inositol/química , Inositol/farmacologia , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
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