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1.
Nat Chem Biol ; 15(6): 556-559, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31086327

RESUMO

Inhibition of the NLRP3 inflammasome is a promising strategy for the development of new treatments for inflammatory diseases. MCC950 is a potent and specific small-molecule inhibitor of the NLRP3 pathway, but its molecular target is not defined. Here, we show that MCC950 directly interacts with the Walker B motif within the NLRP3 NACHT domain, thereby blocking ATP hydrolysis and inhibiting NLRP3 activation and inflammasome formation.


Assuntos
Trifosfato de Adenosina/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Inflamassomos/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Sulfonas/farmacologia , Trifosfato de Adenosina/metabolismo , Sítios de Ligação/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Hidrólise/efeitos dos fármacos , Inflamassomos/biossíntese , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sulfonas/química
2.
Molecules ; 24(9)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052602

RESUMO

In this study, effects of different pretreatment methods on the enzymatic digestibility of Pennisetum alopecuroides, a ubiquitous wild grass in China, were investigated to evaluate its potential as a feedstock for biofuel production. The stalk samples were separately pretreated with H2SO4, NaOH and FeCl3 solutions of different concentrations at 120 °C for 30 min, after which enzymatic hydrolysis was conducted to measure the digestibility of pretreated samples. Results demonstrated that different pretreatments were effective at removing hemicellulose, among which ferric chloride pretreatment (FCP) gave the highest soluble sugar recovery (200.2 mg/g raw stalk) from the pretreatment stage. In comparison with FCP and dilute acid pretreatment (DAP), dilute alkaline pretreatment (DALP) induced much higher delignification and stronger morphological changes of the biomass, making it more accessible to hydrolysis enzymes. As a result, DALP using 1.2% NaOH showed the highest total soluble sugar yield through the whole process from pretreatment to enzymatic hydrolysis (508.5 mg/g raw stalk). The present work indicates that DALP and FCP have the potential to enhance the effective bioconversion of lignocellulosic biomass like P. alopecuroides, hence making this material a valuable and promising energy plant.


Assuntos
Ácidos/farmacologia , Antiácidos/farmacologia , Cloretos/farmacologia , Enzimas/metabolismo , Compostos Férricos/farmacologia , Pennisetum/efeitos dos fármacos , Pennisetum/metabolismo , Biomassa , Fermentação , Hidrólise/efeitos dos fármacos , Açúcares/metabolismo
3.
Carbohydr Polym ; 217: 126-134, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079668

RESUMO

Longan pulp is an excellent source of polysaccharides and other nutrients that have many health benefits. However, longans is susceptible to pulp breakdown after harvest and loses its nutrition values. To solve this problem, this study aimed to study the effects of a novel chitosan, Kadozan, on pulp breakdown index, contents of pectin, cellulose and hemicelluloses, and activities of enzymes in longan pulp relating to disassembly of polysaccharides (XET, PE, PG, ß-Gal, and cellulase). The data illustrated that, compared to the control longans, chitosan-treated longans contained higher amounts of CWM, CSP, ISP, cellulose and hemicelluloses, but exhibited lower pulp breakdown index, lower activities of cell wall-disassembling enzymes, and contained lower WSP amount. These results suggested that Kadozan with a dilution of 1:500 (VKadozan: VKadozan + Water) could significantly decrease activities of disassembling-enzymes and depolymerization of polysaccharides in cell wall, and subsequently alleviate pulp breakdown and prolong storage-life of postharvest longans.


Assuntos
Parede Celular/efeitos dos fármacos , Quitosana/farmacologia , Inibidores Enzimáticos/farmacologia , Frutas/metabolismo , Polissacarídeos/metabolismo , Sapindaceae/metabolismo , Parede Celular/metabolismo , Celulose/metabolismo , Conservação de Alimentos/métodos , Qualidade dos Alimentos , Glicosídeo Hidrolases/antagonistas & inibidores , Hidrólise/efeitos dos fármacos , Pectinas/metabolismo
4.
J Biotechnol ; 296: 42-52, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30885654

RESUMO

The biological conversion of lignocellulose into fermentable sugars is a key process for the sustainable production of biofuels from plant biomass. Polysaccharides in plant feedstock can be valorized using thermostable mixtures of enzymes that degrade the cell walls, thus avoiding harmful and expensive pre-treatments. (Hyper)thermophilic bacteria of the phylum Thermotogae provide a rich source of enzymes for such industrial applications. Here we selected T. neapolitana as a source of hyperthermophilic hemicellulases for the degradation of lignocellulosic biomass. Two genes encoding putative hemicellulases were cloned from T. neapolitana genomic DNA and expressed in Escherichia coli. Further characterization revealed that the genes encoded an endo-1,4-ß-galactanase and an α-l-arabinofuranosidase with optimal temperatures of ˜90 °C and high turnover numbers during catalysis (kcat values of ˜177 and ˜133 s-1, respectively, on soluble substrates). These enzymes were combined with three additional T. neapolitana hyperthermophilic hemicellulases - endo-1,4-ß-xylanase (XynA), endo-1,4-ß-mannanase (ManB/Man5A) and ß-glucosidase (GghA) - to form a highly thermostable hemicellulolytic blend. The treatment of barley straw and corn bran with this enzymatic cocktail resulted in the solubilization of multiple hemicelluloses and boosted the yield of fermentable sugars by up to 65% when the complex substrates were further degraded by cellulases.


Assuntos
Celulase/química , Glicosídeo Hidrolases/química , Lignina/química , Polissacarídeos/química , Biocombustíveis , Biomassa , Celulase/genética , Estabilidade Enzimática/genética , Escherichia coli/genética , Fermentação , Glicosídeo Hidrolases/genética , Hidrólise/efeitos dos fármacos , Polissacarídeos/genética , Temperatura Ambiente , Thermotoga neapolitana/enzimologia , Thermotoga neapolitana/genética
5.
Int J Mol Sci ; 20(6)2019 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-30884876

RESUMO

Artificial light at night (ALAN) is an increasing phenomenon worldwide that can cause a series of biological and ecological effects, yet little is known about its potential interaction with other stressors in aquatic ecosystems. Here, we tested whether the impact of lead (Pb) on litter decomposition was altered by ALAN exposure using an indoor microcosm experiment. The results showed that ALAN exposure alone significantly increased leaf litter decomposition, decreased the lignin content of leaf litter, and altered fungal community composition and structure. The decomposition rate was 51% higher in Pb with ALAN exposure treatments than in Pb without ALAN treatments, resulting in increased microbial biomass, ß-glucosidase (ß-G) activity, and the enhanced correlation between ß-G and litter decomposition rate. These results indicate that the negative effect of Pb on leaf litter decomposition in aquatic ecosystems may be alleviated by ALAN. In addition, ALAN exposure also alters the correlation among fungi associated with leaf litter decomposition. In summary, this study expands our understanding of Pb toxicity on litter decomposition in freshwater ecosystems and highlights the importance of considering ALAN when assessing environmental metal pollutions.


Assuntos
Água Doce/análise , Água Doce/microbiologia , Chumbo/toxicidade , Iluminação , Biomassa , Ecossistema , Poluição Ambiental/efeitos adversos , Poluição Ambiental/análise , Fungos/efeitos dos fármacos , Fungos/genética , Fungos/isolamento & purificação , Fungos/efeitos da radiação , Hidrólise/efeitos dos fármacos , Hidrólise/efeitos da radiação , Iluminação/efeitos adversos , Iluminação/métodos , Lignina/análise , Metagenômica , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/efeitos da radiação
6.
Int J Biol Macromol ; 129: 634-644, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30738163

RESUMO

Efficient production of sugar monomers from lignocellulose is often hampered by serious bottle-necks in biomass hydrolysis. The present study reveals that ultra-sonication assisted pretreatment following autoclaving, termed as combined pretreatment, can lead to more efficient delignification of lignocellulosic biomass and an open, deformed polysaccharide matrix, found favorable for subsequent enzymatic hydrolysis, is formed. The pattern of inhibition for the enzymatic hydrolysis reaction on combined-pretreated saw dust is identified. Two main inhibition models (competitive and noncompetitive) are proposed and a better fit of experimental values with the theoretical values for the competitive inhibition model validates the proposition that in the present experiment, glucose inhibits the enzymes competitively. Additionally, accuracy of the inhibitory kinetics based models is estimated over a series of enzyme and substrate concentrations.


Assuntos
Biomassa , Celulase/metabolismo , Glucose/farmacologia , Lignina/química , Xilose/farmacologia , Celulase/antagonistas & inibidores , Hidrólise/efeitos dos fármacos , Cinética , Morus/química , Sonicação
7.
Int J Biol Macromol ; 129: 433-441, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30716375

RESUMO

The objective of this study was to investigate the porcine pancreatic α-amylase (PPA) inhibitory activity of botanical food proteins, represented by soy protein isolate (SPI) and wheat gluten protein (WGP). The half maximal inhibitory concentration (IC50) was determined, and the kinetics of inhibition were investigated using Dixon, Cornish-Bowden, and Lineweaver-Burk plots. The results showed WGP functioned as mixed-type inhibitors with both competitive and uncompetitive inhibitory characteristics, while SPI showed competitive inhibitory effects on α-amylase. The competitive inhibition constants (Kic) of WGP and SPI were 5.753 and 30.212 mg/mL, respectively, and the uncompetitive inhibition constants (Kiu) of WGP was 45.110 mg/mL, respectively. The IC50 values of WGP and SPI were 3.086 and 33.899 mg/mL, respectively. For WGP, the lower Kic vs. Kiu for mixed-type inhibitors suggested that they bound more tightly to free PPA than the PPA-starch complex. Compared with SPI, WGP displayed a stronger inhibitory effect on α-amylase. These results indicated that SPI and WGP may delay the digestion of starchy foods by inhibiting starch hydrolytic enzymes, which may be of relevance in vivo during gastrointestinal digestion. The findings are also of important practical value for the development of carbohydrate-restricted diet and protein-based functional foods.


Assuntos
Inibidores Enzimáticos/farmacologia , Glutens/farmacologia , Proteínas de Soja/isolamento & purificação , Proteínas de Soja/farmacologia , Triticum/química , alfa-Amilases/antagonistas & inibidores , Hidrólise/efeitos dos fármacos , Cinética , Amido/metabolismo , Zea mays/química
8.
Chemosphere ; 219: 305-312, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30543966

RESUMO

Extensive studies on anaerobic fermentation of waste activated sludge (WAS) for volatile fatty acids (VFAs) production focused on the effects of operating parameters and pretreatment methods, and little information is available for those of organic pollutants which were absorbed on sludge. The influence of sulfadiazine (SDZ), a typical antibiotic pollutant in WAS, on VFAs production during anaerobic fermentation was investigated in this study. The accumulation of VFAs was remarkably affected in the presence of SDZ. When the content of SDZ was 50 mg per kilogram dry sludge the concentration of VFAs from sludge was 2032.8 mg COD/L, much higher than that of control (1540.2 mg COD/L). Mechanism investigation revealed that the content of extracellular polymeric substances (EPS) from sludge was increased due to the presence of SDZ, which provided more substrates, i.e., protein and carbohydrate, and created a favorable environment for anaerobes. The hydrolysis and acidification of WAS were stimulated by SDZ, and the functional microorganisms were advantageous to VFAs production. The activities of protease, α-glucosidase and acetate kinase were promoted when SDZ occurred, which were beneficial for hydrolysis and acidification. The effect of SDZ on pure strains further confirmed that the formation of VFAs during anaerobic fermentation was stimulated by SDZ.


Assuntos
Ácidos Graxos Voláteis/biossíntese , Fermentação/efeitos dos fármacos , Esgotos/microbiologia , Sulfadiazina/farmacologia , Bactérias Anaeróbias/metabolismo , Ácidos Graxos Voláteis/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise/efeitos dos fármacos , Esgotos/química , Sulfadiazina/metabolismo
9.
Mar Drugs ; 16(7)2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973522

RESUMO

Hypertension can cause coronary heart disease. Synthetic angiotensin-converting enzyme (ACE) inhibitors are effective antihypertensive drugs but often cause side effects. The aim of this study was to prepare potential ACE inhibitors from scales. Gelatin was extracted from lizardfish scales. Then, scale gelatin was enzymolyzed to prepare ACE inhibitory peptides using response surface methodology. Proteolytic conditions after optimization were as follows: pH 7.0, enzyme substrate ratio 3.2%, temperature 47 °C, and proteolysis lasting 2 h and 50 min. The experimental ACE inhibitory activity under optimal conditions was 86.0 ± 0.4%. Among the 118 peptides identified from gelatin hydrolysates, 87.3% were hydrophilic and 93.22% had a molecular weight <2000 Da. Gelatin peptides had high stability upon exposure to high temperature and pH as well as gastrointestinal tract enzymes. Gelatin peptides showed an antihypertensive effect in spontaneously hypertensive rats at a dosage of 2 g/kg in the long-term experiments. A new ACE inhibitory peptide was isolated from gelatin hydrolysates, and was identified as AGPPGSDGQPGAK with an IC50 value of 420 ± 20 μM. In this way, ACE inhibitory peptides derived from scale gelatin have the potential to be used as healthy ACE-inhibiting drug raw materials.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/metabolismo , Anti-Hipertensivos/metabolismo , Cordados/metabolismo , Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Anti-Hipertensivos/farmacologia , Gelatina/metabolismo , Gelatina/farmacologia , Hidrólise/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Masculino , Peptídeos/farmacologia , Hidrolisados de Proteína/metabolismo , Ratos , Ratos Endogâmicos SHR
10.
J Fish Biol ; 93(2): 290-301, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29968318

RESUMO

This study was conducted to assess the effect of eicosapentaenoic acid (20:5n-3, EPA) on lipid accumulation in grass carp Ctenopharyngodon idella adipose tissue both in vitro and in vivo. EPA was observed to inhibit the adipocyte viability in a time and dose-dependent manner. EPA was also found to induce reactive oxygen species accumulation in vitro. The mRNA levels of caspase 3a and caspase 3b, as well as the activity of Caspase 3 increased significantly in vitro and in vivo, whereas the value of B cell leukemia 2-Bcl-2 associated X protein decreased significantly. Besides, the pro-apoptotic effect was relieved by α-tocopherol. Dietary 0.52% EPA had no apparent effect on intraperitoneal fat index. Moreover, EPA promoted the hydrolytic gene expressions in vitro and in vivo, including adipose triglyceride lipase and hormone sensitive lipase-a. Meanwhile, the lipogenic gene expressions of liver X receptor α, sterol regulatory element binding protein-1c and fatty-acid synthase were down-regulated by EPA in vitro and in vivo. However, EPA also acted to promote the marker gene expressions of adipogenesis, including peroxisome proliferator-activated receptor γ and lipoprotein lipase in vitro and in vivo. Contents of EPA increased significantly in the treatment groups in vitro and in vivo. These results support that EPA affects multiple aspects of lipid metabolism, including hydrolysis, lipogenesis, adipogenesis and apoptosis. However, it barely functioned in decreasing the lipid accumulation of Ctenopharyngodon idella under the current culture conditions.


Assuntos
Tecido Adiposo/metabolismo , Carpas/metabolismo , Ácido Eicosapentaenoico/metabolismo , Metabolismo dos Lipídeos , Adipócitos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Dieta , Ácido Eicosapentaenoico/administração & dosagem , Ácidos Graxos/biossíntese , Hidrólise/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
11.
J Pharm Biomed Anal ; 157: 27-35, 2018 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-29754040

RESUMO

Clandestine laboratories continue producing new synthetic cannabinoids that mimic and magnify natural cannabinoids effects to circumvent drug scheduling legislation. New synthetic cannabinoids are highly potent and responsible for many acute intoxications and deaths. Characterization of metabolic pathways is critical to identify metabolite markers whose detection can prove intake. BB-22 is a new potent synthetic cannabinoid whose toxicological and metabolic properties are currently unavailable. Analytical methods require constant updating and are challenging due to extensive synthetic cannabinoid metabolism and low marker concentrations. A single non-specific BB-22 metabolite was previously identified in incubations with human liver microsomes (BB-22 3-carboxyindole). Clear characterization of BB-22's metabolism is required to help toxicologists document BB-22 consumption in clinical and forensic cases. We incubated 10 µmol/L BB-22 with cryopreserved human hepatocytes for 3 h. Samples were analyzed by liquid chromatography on a biphenyl column and high resolution mass spectrometry. Results were processed with data mining software, identifying ten metabolites. Loss of the quinolinyl side-chain via ester hydrolysis was the main biotransformation. All other metabolites were produced by further indole or cyclohexylmethyl hydroxylation or glucuronidation. We recommend BB-22 3-carboxyindole and two BB-22 3-carboxyindole-hydroxycyclohexylmethyl isomers as metabolite targets for documenting BB-22 intake. Hydrolysis of biological samples before analysis is strongly suggested to improve detection of phase I metabolites. BB-22 3-carboxyindole is not specific for BB-22 intake, as it was previously detected as a minor MDMB-CHMICA and ADB-CHMICA metabolite. Consumption of these two synthetic cannabinoids should be ruled out to confirm BB-22 intake.


Assuntos
Canabinoides/química , Canabinoides/metabolismo , Hepatócitos/metabolismo , Indóis/química , Indóis/metabolismo , Quinolinas/química , Quinolinas/metabolismo , Biomarcadores/química , Biomarcadores/metabolismo , Cromatografia Líquida/métodos , Criopreservação , Humanos , Hidrólise/efeitos dos fármacos , Hidroxilação/efeitos dos fármacos , Desentoxicação Metabólica Fase I/fisiologia , Microssomos Hepáticos/metabolismo , Espectrometria de Massas em Tandem/métodos
12.
Naunyn Schmiedebergs Arch Pharmacol ; 391(9): 891-905, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29808231

RESUMO

Previous results indicate that the phosphodiesterase PDE3B hydrolyzes cUMP. Also, almost 50 years ago, cUMP-hydrolytic activity was observed in rat adipose tissue. We intended to characterize the enzyme kinetics of PDE3B-mediated cUMP hydrolysis, to determine the PDE3B binding mode of cUMP, and to analyze cUMP hydrolysis in adipocyte preparations. Educts (cNMPs) and products (NMPs) of the PDE reactions as well as intracellular cNMPs were quantitated by HPLC-coupled tandem mass spectrometry. PDE3B expression was determined by qPCR and Western blot. Docking studies were performed with the PDE3B crystal structure PDB ID 1SO2 (complex with a dihydropyridazine inhibitor). PDE3B hydrolyzed cUMP (Km ~ 550 µM, Vmax ~ 76 µmol/min/mg) and cAMP (Km ~ 0.7 µM, Vmax ~ 4.3 µmol/min/mg) in a milrinone (PDE3-selective inhibitor)-sensitive manner (Ki for inhibition of cUMP hydrolysis: 205 nM). cUMP forms one hydrogen bond with PDE3B (uracil 3-NH with side chain oxygen of Q988). Two hydrogen bonds stabilize cAMP binding. cCMP does not interact with PDE3B. Possibly, the cytosine base cannot form hydrogen bonds with PDE3B, and the 4-NH2 group clashes with L987 of the enzyme. Adipocyte differentiation of 3T3-L1 MBX cells increased mRNA of PDE3B, but not of PDE3A. Significant amounts of cUMP were detected in differentiated and undifferentiated 3T3-L1 MBX cells. 3T3-L1 MBX adipocyte lysates and rat epididymal adipose tissue membranes contained milrinone-sensitive cUMP-hydrolytic activity. PDE3B is a low-affinity and high-velocity phosphodiesterase for cUMP. The cUMP-hydrolyzing activity described almost 50 years ago for rat adipose tissue is caused by PDE3, probably by the isoform PDE3B.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/farmacologia , Nucleotídeos Cíclicos/metabolismo , Uridina Monofosfato/metabolismo , Células 3T3-L1 , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Hidrólise/efeitos dos fármacos , Masculino , Camundongos , Modelos Moleculares , Ratos , Proteínas Recombinantes/farmacologia
13.
J Biosci Bioeng ; 126(3): 346-354, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29657125

RESUMO

Lignocellulosic biomass pretreatment with deep eutectic solvents (DESs) is a promising and challenging process for production of biofuels and valuable platform chemicals. In this work, rice straw was mainly fractionated into carbohydrate-rich materials (CRMs) and lignin-rich materials (LRMs) by 90% lactic acid/choline chloride (LC)-water solution with different molar ratio of hydrogen bond donor (HBD, lactic acid) and hydrogen bond acceptor (HBA, choline chloride). It was found that high HBD/HBA molar ratio of DESs was favorable for achieving CRMs and LRMs with high purity, and both HBD and HBA were responsible for effective biomass fractionation possibly due to their synergistic effect on highly efficient breakage of the linkage between hemicellulose and lignin and thus lignin extraction. About 30%-35% of lignin in native rice straw was fractionated as LRMs, and exceeding 70% of xylan were removed and fractionated into the liquid stream as forms of xylose, furfural and humins after pretreatment using aqueous LC (3:1, 5:1) solution. Consequently, polysaccharides enzymatic hydrolysis of the CRMs were significantly enhanced. Moreover, all the DESs could be recovered with high yields of around 90%, and 69% of the LC (3:1) was recovered after 5 cycles reuse at 90 °C. Besides, the recycled DES maintained a good pretreatment ability, and glucose yields of 60-70% were achieved in the enzymatic hydrolysis of CRMs obtained in each cycle. The facile process established in present work is promising for large scale production of fermentable sugars and other chemicals.


Assuntos
Biomassa , Fracionamento Químico/métodos , Oryza/química , Polissacarídeos/metabolismo , Reciclagem , Solventes/farmacologia , Biocombustíveis , Carboidratos/química , Glucose/química , Glucose/metabolismo , Hidrólise/efeitos dos fármacos , Lignina/química , Oryza/enzimologia , Polissacarídeos/química , Reciclagem/métodos , Solventes/química , Xilose/química , Xilose/metabolismo
14.
Carbohydr Polym ; 192: 273-281, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29691021

RESUMO

Miscanthus is a leading bioenergy crop and rice provides enormous biomass for biofuels. Using Calcofluor White staining, this work in situ observed an initial lignocellulose hydrolysis in two distinct Miscanthus accessions, rice cultivar (NPB), and Osfc16 mutant after mild chemical pretreatments. In comparison, the M. sin and Osfc16 respectively exhibited weak Calcofluor fluorescence compared to the M. sac and NPB during enzymatic hydrolysis, consistent with the high biomass saccharification detected in vitro. Using xyloglucan-directed monoclonal antibodies (mAbs), xyloglucan deconstruction was observed from initial cellulose hydrolysis, whereas the M. sin and Osfc16 exhibited relatively strong immunolabeling using xylan-directed mAb, confirming previous findings of xylan positive impacts on biomass saccharification. Furthermore, the M. sin showed quick disappearance of RG-I immunolabeling with varied HG labelings between acid and alkali pretreatments. Hence, this study demonstrated a quick approach to explore wall polymer distinct deconstruction for enhanced biomass saccharification under chemical pretreatment in bioenergy crops.


Assuntos
Biomassa , Biopolímeros/metabolismo , Parede Celular/metabolismo , Oryza/citologia , Oryza/efeitos dos fármacos , Poaceae/citologia , Poaceae/efeitos dos fármacos , Metabolismo dos Carboidratos/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Celulose/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise/efeitos dos fármacos , Hidróxidos/farmacologia , Oryza/metabolismo , Poaceae/metabolismo , Compostos de Potássio/farmacologia
15.
Mar Drugs ; 16(4)2018 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-29662015

RESUMO

As an important glycosaminoglycan, keratan sulfate (KS) mainly exists in corneal and cartilage, possessing various biological activities. In this study, we purified KS from blue shark (Prionace glauca) cartilage and prepared KS oligosaccharides (KSO) through keratanase II-catalyzed hydrolysis. The structures of KS and KSO were characterized using multi-dimensional nuclear magnetic resonance (NMR) spectra and liquid chromatography-mass spectrometry (LC-MS). Shark cartilage KS was highly sulfated and modified with ~2.69% N-acetylneuraminic acid (NeuAc) through α(2,3)-linked to galactose. Additionally, KS exhibited binding affinity to Ricinus communis agglutinin I (RCA120) in a concentration-dependent manner, a highly toxic lectin from beans of the castor plant. Furthermore, KSO from dp2 to dp8 bound to RCA120 in the increasing trend while the binding affinity of dp8 was superior to polysaccharide. These results define novel structural features for KS from Prionace glauca cartilage and demonstrate the potential application on ricin-antidote exploitation.


Assuntos
Cartilagem/química , Sulfato de Ceratano/química , Lectinas de Plantas/química , Tubarões/metabolismo , Acetilglucosaminidase/química , Animais , Cromatografia Líquida , Galactose/química , Hidrólise/efeitos dos fármacos , Espectroscopia de Ressonância Magnética/métodos , Oligossacarídeos/química , Espectrometria de Massas em Tandem/métodos
16.
Mar Drugs ; 16(4)2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29662025

RESUMO

Enzymatic preparation of alginate oligosaccharides with versatile bioactivities by alginate lyases has attracted increasing attention due to its featured characteristics, such as wild condition and specific products. In this study, AlgNJ-07, a novel polyM-specific alginate lyase with high specific activity and pH stability, has been purified from the newly isolated marine bacterium Serratia marcescens NJ-07. It has a molecular weight of approximately 25 kDa and exhibits the maximal activity of 2742.5 U/mg towards sodium alginate under 40 °C at pH 9.0. Additionally, AlgNJ-07 could retain more than 95% of its activity at pH range of 8.0-10.0, indicating it possesses excellent pH-stability. Moreover, it shows high activity and affinity towards polyM block and no activity to polyG block, which suggests that it is a strict polyM-specific alginate lyase. The degradation pattern of AlgNJ-07 has also been explored. The activity of AlgNJ-07 could be activated by NaCl with a low concentration (100-300 mM). It can be observed that AlgNJ-07 can recognize the trisaccharide as the minimal substrate and hydrolyze the trisaccharide into monosaccharide and disaccharide. The TLC and ESI-MS analysis indicate that it can hydrolyze substrates in a unique endolytic manner, producing not only oligosaccharides with Dp of 2-5 but also a large fraction of monosaccharide. Therefore, it may be a potent tool to produce alginate oligosaccharides with lower Dps (degree of polymerization).


Assuntos
Alginatos/química , Proteínas de Bactérias/química , Serratia marcescens/química , Dissacarídeos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Hidrólise/efeitos dos fármacos , Peso Molecular , Monossacarídeos/química , Oligossacarídeos/química , Polissacarídeo-Liase/química , Cloreto de Sódio/química , Especificidade por Substrato
17.
Drug Metab Dispos ; 46(5): 532-541, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29490903

RESUMO

Verinurad (RDEA3170) is a second generation selective uric acid reabsorption inhibitor for the treatment of gout and asymptomatic hyperuricemia. Following a single oral solution of 10-mg dose of [14C]verinurad (500 µCi), verinurad was rapidly absorbed with a median time to occurrence of maximum observed concentration (Tmax) of 0.5 hours and terminal half-life of 15 hours. In plasma, verinurad constituted 21% of total radioactivity. Recovery of radioactivity in urine and feces was 97.1%. Unchanged verinurad was the predominant component in the feces (29.9%), whereas levels were low in the urine (1.2% excreted). Acylglucuronide metabolites M1 (direct glucuronidation) and M8 (glucuronidation of N-oxide) were formed rapidly after absorption of verinurad with terminal half-life values of approximately 13 and 18 hours, respectively. M1 and M8 constituted 32% and 31% of total radioactivity in plasma and were equimolar to verinurad on the basis of AUC ratios. M1 and M8 formed in the liver were biliary cleared with complete hydrolysis in the GI tract, as metabolites were not detected in the feces and/or efflux across the sinusoidal membrane; M1 and M8 accounted for 29.2% and 32.5% of the radioactive dose in urine, respectively. In vitro studies demonstrated that CYP3A4 mediated the formation of the N-oxide metabolite (M4), which was further metabolized by glucuronyl transferases (UGTs) to form M8, as M4 was absent in plasma and only trace levels were present in the urine. Several UGTs mediated the formation of M1, which could also be further metabolized by CYP2C8. Overall, the major clearance route of verinurad is metabolism via UGTs and CYP3A4 and CYP2C8.


Assuntos
Ácido Úrico/metabolismo , Uricosúricos/metabolismo , Radioisótopos de Carbono/metabolismo , Citocromo P-450 CYP2C8/metabolismo , Citocromo P-450 CYP3A/metabolismo , Fezes , Trato Gastrointestinal/metabolismo , Glucuronídeos/metabolismo , Glucuronosiltransferase/metabolismo , Gota/tratamento farmacológico , Gota/metabolismo , Meia-Vida , Humanos , Hidrólise/efeitos dos fármacos , Hiperuricemia/tratamento farmacológico , Hiperuricemia/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Taxa de Depuração Metabólica/fisiologia , Uricosúricos/uso terapêutico
18.
Dokl Biochem Biophys ; 478(1): 8-13, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29536300

RESUMO

The effect of iron nitrosyl complexes, NO donors, of a general formula [Fe2(L)2(NO)4] with functional sulfur-containing ligands (L-3-nitro-phenol-2-yl, 4-nitro-phenol-2-yl, or 1-methyl-tetrazol-5-yl) on the activity of sarcoplasmic reticulum Ca2+-ATPase and cyclic guanosine monophosphate phosphodiesterase (cGMP PDE) was studied. The test complexes uncoupled the hydrolytic and transport functions of Ca2+- ATPase, thus disturbing the balance of Ca2+ ions in cells, which may affect the formation of thrombi and adhesion of metastatic cells to the endothelium of capillaries. They also inhibited the activity of cGMP PDE, thereby contributing to the accumulation of the second messenger cGMP. The studied iron nitrosyl complexes can be considered as potential drugs.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , GMP Cíclico/metabolismo , Ferro/farmacologia , Doadores de Óxido Nítrico/farmacologia , Óxidos de Nitrogênio/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Retículo Sarcoplasmático/enzimologia , Animais , Humanos , Hidrólise/efeitos dos fármacos
19.
Biol Pharm Bull ; 41(2): 208-212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29386480

RESUMO

Mume fruit, the Japanese apricot (Prunus mume SIEB. et ZUCC.), is popular in Japan and is mostly consumed in the pickled form called umeboshi. This fruit is known to have anti-microbial properties, but the principal constituents responsible for the antimicrobial properties have not yet been elucidated. We investigated the antimicrobial activities of the phenolic compounds in P. mume against enterobacteria. In this study, growth inhibitory activities were measured as an index of the antibacterial activities. The phenolic compounds were prepared from a byproduct of umeboshi called umesu or umezu (often translated as "mume vinegar"). Umesu or umezu phenolics (UP) contain approximately 20% phenolic compounds with p-coumaric acid as a standard and do not contain citric acid. We observed the inhibitory effects of UP against the growth of some enterobacteria, at a relatively high concentration (1250-5000 µg/mL). Alkali hydrolysates of UP (AHUP) exhibited similar antibacterial activities, but at much lower concentrations of 37.5-300 µg/mL. Since AHUP comprises hydroxycinnamic acids such as caffeic acid, p-coumaric acid, and ferulic acid, the antibacterial activities of each of these acids were examined. Our study shows that the phenolic compounds in P. mume other than citric acid contribute to its antimicrobial activity against enterobacteria in the digestive tract.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas , Enterobacteriaceae/efeitos dos fármacos , Alimentos em Conserva/análise , Frutas/química , Fenóis/farmacologia , Prunus/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Ácidos Cumáricos/isolamento & purificação , Ácidos Cumáricos/farmacologia , Enterobacteriaceae/crescimento & desenvolvimento , Etnofarmacologia , Indústria de Processamento de Alimentos/economia , Liofilização , Hidrólise/efeitos dos fármacos , Indicadores e Reagentes/química , Resíduos Industriais/análise , Resíduos Industriais/economia , Japão , Medicina Tradicional do Leste Asiático , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Hidróxido de Sódio/química
20.
PLoS One ; 13(2): e0193343, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29474492

RESUMO

It is well known that saturated fatty acids (SFAs) and unsaturated fatty acid, in particular omega-3 polyunsaturated fatty acids (n-3 PUFAs), have different effects on inflammatory signaling: SFAs are pro-inflammatory but n-3 PUFAs have strong anti-inflammatory properties. We have reported that palmitic acid (PA), a saturated fatty acid, robustly amplifies lipopolysaccharide (LPS) signaling to upregulate proinflammatory gene expression in macrophages. We also reported that the increased production of ceramide (CER) via sphingomyelin (SM) hydrolysis and CER de novo synthesis plays a key role in the synergistic effect of LPS and PA on proinflammatory gene expression. However, it remains unclear if n-3 PUFAs are capable of antagonizing the synergistic effect of LPS and PA on gene expression and CER production. In this study, we employed the above macrophage culture system and lipidomical analysis to assess the effect of n-3 PUFAs on proinflammatory gene expression and CER production stimulated by LPS and PA. Results showed that DHA strongly inhibited the synergistic effect of LPS and PA on proinflammatory gene expression by targeting nuclear factor kappa B (NFκB)-dependent gene transcription. Results also showed that DHA inhibited the cooperative effect of LPS and PA on CER production by targeting CER de novo synthesis, but not SM hydrolysis. Furthermore, results showed that myriocin, a specific inhibitor of serine palmitoyltransferase, strongly inhibited both LPS-PA-stimulated CER synthesis and proinflammatory gene expression, indicating that CER synthesis is associated with proinflammatory gene expression and that inhibition of CER synthesis contributes to DHA-inhibited proinflammatory gene expression. Taken together, this study demonstrates that DHA antagonizes the boosting effect of PA on LPS signaling on proinflammatory gene expression by targeting both NFκB-dependent transcription and CER de novo synthesis in macrophages.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ceramidas/biossíntese , Ácidos Docosa-Hexaenoicos/farmacologia , Inflamação/tratamento farmacológico , Ácido Palmítico/antagonistas & inibidores , Transcrição Genética/efeitos dos fármacos , Animais , Linhagem Celular , Inibidores Enzimáticos/toxicidade , Hidrólise/efeitos dos fármacos , Inflamação/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Camundongos , NF-kappa B/metabolismo , Ácido Palmítico/toxicidade , Esfingomielinas/metabolismo
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