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1.
Anim Genet ; 54(4): 435-445, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36911996

RESUMO

The number of ribs (NR) and carcass length (CL) are important economic traits in pig breeding programs. Pigs with a higher NR and longer CL produce greater pork yields. In the present study, Suhuai pigs with NR and CL phenotypes were genotyped using the Neogen® GGP Porcine 80 K SNP array to identify the QTL affecting NR and CL and dissect the candidate genes for the two traits. The SNP-chip data was imputed to the whole-genome sequence (iWGS) to increase the probability of identifying causal variants. Through genome-wide association studies (GWAS) based on both chip and iWGS data, significant SNPs were detected on Sus scrofa chromosome (SSC) 1, SSC4 and SSC7 for NR and on SSC5, SSC16 and SSC17 for CL. Moreover, two SNPs (H3GA0022644 and WU_10.2_7_103460706) on SSC7 detected in chip-based GWAS were significantly associated with both NR and CL. Through Bayes fine mapping, one reported QTL for NR on SSC7 and two reported QTL for CL on SSC17 were verified, and two new QTL (SSC1: 14.05-15.84 Mb and SSC4: 64.83-66.59 Mb) affecting NR and two new QTL (SSC5: 58.31-59.84 Mb and SSC16: 22.98-23.43 Mb) affecting CL were detected. According to the biological functions of genes, MTHFD1L on SSC1 and SULF1 on SSC4 are novel functional candidate genes for NR, and EMP1 on SSC5 and EGFLAM on SSC16 are novel functional candidate genes for CL. Overall, our findings provide a basis for identifying new causal genes and mutations affecting NR and CL.


Assuntos
Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Animais , Suínos/genética , Estudo de Associação Genômica Ampla/veterinária , Teorema de Bayes , Genótipo , Fenótipo , Costelas , Polimorfismo de Nucleotídeo Único , Sus scrofa/genética
2.
Water Sci Technol ; 82(3): 492-502, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32960794

RESUMO

In this work, a user-friendly chitin-based adsorbent (CT-PmPD) was synthesized by in-situ polymerization of m-phenylenediamine on chitin bead, which could effectively remove Cr(VI) from water. The structure and morphology of the CT-PmPD were characterized by FT-IR, XRD, SEM, zeta potential and XPS. Specifically, the effect of adsorbed dosage, pH, contact time, adsorption temperature and coexisting salt on the adsorption of Cr(VI) were studied. Besides, the adsorption mechanism of CT-PmPD toward Cr(VI) were also analyzed. Consequently, CT-PmPD exhibited a monolayer adsorption and the Langmuir model fitted a Cr(VI) adsorption capacity reaching 185.4 mg/g at 298 K. The high adsorption capacity was attributed to the abundant amino groups of CT-PmPD, which could be protonated to boost the electrostatic attraction of Cr(VI) oxyanions, thus providing electron to reduce Cr(VI). Additionally, the CT-PmPD revealed a good regeneration and reusability capacity, maintaining most of its adsorption capacity even after five cycles of adsorption-desorption. This high adsorption capacity and excellent regeneration performance highlighted the great potential of CT-PmPD for the removal of Cr(VI).


Assuntos
Quitina , Poluentes Químicos da Água/análise , Adsorção , Cromo , Cinética , Fenilenodiaminas , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Arch Pharm (Weinheim) ; 349(5): 356-62, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26991997

RESUMO

A series of 4-(piperazin-1-yl)-7H-pyrrolo[2,3-d]pyrimidine derivatives was synthesized and evaluated as Akt inhibitors by optimization of a weak screening lead (1). Typically, compounds 5q and 5t significantly improved the Akt1 inhibitory potency with IC50 values of 18.0 and 21.3 nM, respectively, with desirable antiproliferative effect against the cell lines LNCaP and PC-3. The inhibitors 5q and 5t might serve as lead compounds for further exploration of Akt inhibitors as anticancer agents.


Assuntos
Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Pirimidinas/farmacologia , Pirróis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Pirimidinas/síntese química , Pirróis/síntese química , Relação Estrutura-Atividade
4.
Chembiochem ; 16(4): 670-6, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25683962

RESUMO

A supramolecular artificial glutathione peroxidase (PNIPAM-CD-g-Te) was prepared based on a supramolecular graft copolymer. PNIPAM-CD-g-Te was constructed by supramolecular host-guest self-assembly. Significantly, PNIPAM-CD-g-Te displayed noticeable temperature-dependent catalytic activity and typical saturation kinetics behavior. It was also proved that the change in the self-assembled structure of PNIPAM-CD-g-Te during the temperature-dependent process played a significant role in the temperature-dependent catalytic behavior. The construction of PNIPAM-CD-g-Te based on supramolecular graft copolymer endows artificial GPx with temperature-dependent catalytic ability, enriched catalytic centers, and homogeneously distributed catalytic centers. This work bodes well for the development of other biologically related host-guest supramolecular biomaterials.


Assuntos
Resinas Acrílicas/química , Materiais Biomiméticos/química , Ciclodextrinas/química , Glutationa Peroxidase/química , Telúrio/química , Catálise , Cinética , Temperatura
5.
Soft Matter ; 11(26): 5301-12, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26053236

RESUMO

In an effort to construct smart artificial glutathione peroxidase (GPx) featuring high catalytic activity in an efficient preparation process, an artificial microgel GPx (PPAM-ADA-Te) has been prepared using a supramolecular host-guest self-assembly technique. Herein, 6,6'-telluro-bis(6-deoxy-ß-cyclodextrin) (CD-Te-CD) was selected as a tellurium-containing host molecule, which also served as the crosslinker for the scaffold of the supramolecular microgel. And an adamantane-containing block copolymer (PPAM-ADA) was designed and synthesized as a guest building block copolymer. Subsequently, PPAM-ADA-Te was constructed through the self-assembly of CD-Te-CD and PPAM-ADA. The formation of this self-assembled construct was confirmed by dynamic light scattering, NMR, SEM and TEM. Notably, PPAM-ADA-Te not only exhibits a significant temperature responsive catalytic activity, but also features the characteristic saturation kinetics behaviour similar to that of a natural enzyme catalyst. We demonstrate in this paper that both the hydrophobic microenvironment and the crosslinker in this supramolecular microgel network played significant roles in enhancing and altering the temperature responsive catalytic behaviour. The successful construction of PPAM-ADA-Te not only provides a novel method for the preparation of microgel artificial GPx with high catalytic activity but also provides properties suitable for the future development of intelligent antioxidant drugs.


Assuntos
Materiais Biomiméticos/química , Glutationa Peroxidase/metabolismo , Adamantano/química , Catálise , Desenho de Fármacos , Géis , Cinética , Modelos Moleculares , Conformação Molecular , Polímeros/química , Telúrio/química , beta-Ciclodextrinas/química
6.
Soft Matter ; 10(19): 3374-85, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24652520

RESUMO

Glutathione peroxidase (GPx) protects cells from oxidative damage by scavenging surplus reactive oxygen species (ROS). Commonly, an appropriate amount of ROS acts as a signal molecule in the metabolism. A smart artificial GPx exhibits adjustable catalytic activity, which can potentially reduce the amount of ROS to an appropriate degree and maintain its important physiological functions in metabolism. To construct an optimum and excellent smart artificial GPx, a novel supramolecular microgel artificial GPx (SM-Te) was prepared based on the supramolecular host-guest interaction employing the tellurium-containing guest molecule (ADA-Te-ADA) and the cyclodextrin-containing host block copolymer (poly(N-isopropylacrylamide)-b-[polyacrylamides-co-poly(6-o-(triethylene glycol monoacrylate ether)-ß-cyclodextrin)], PPAM-CD) as building blocks. Subsequently, based on these building blocks, SM-Te was constructed and the formation of its self-assembled structure was confirmed by dynamic light scattering, NMR, SEM, TEM, etc. Typically, benefitting from the temperature responsive properties of the PNIPAM scaffold, SM-Te also exhibited similar temperature responsive behaviour. Importantly, the GPx catalytic rates of SM-Te displayed a noticeable temperature responsive characteristic. Moreover, SM-Te exhibited the typical saturation kinetics behaviour of a real enzyme catalyst. It was proved that the changes of the hydrophobic microenvironment and the pore size in the supramolecular microgel network of SM-Te played significant roles in altering the temperature responsive catalytic behaviour. The successful construction of SM-Te not only overcomes the insurmountable disadvantages existing in previous covalent bond crosslinked microgel artificial GPx but also bodes well for the development of novel intelligent antioxidant drugs.


Assuntos
Materiais Biocompatíveis/química , Géis/química , Resinas Acrílicas/química , Materiais Biocompatíveis/metabolismo , Catálise , Celulose/química , Ciclodextrinas/química , Glutationa Peroxidase/química , Glutationa Peroxidase/metabolismo , Cinética , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Polímeros/síntese química , Polímeros/química , Telúrio/química , Temperatura
7.
Bioorg Khim ; 40(2): 178-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25895337

RESUMO

A novel guest biomimetic glutathione peroxidase (3,3'-tellurobis(propane-3,1-diyl) diadamantanecarboxylate, denoted as ADA-Te-ADA) was synthesized. ADA-Te-ADA functioned to overcome the disadvantages in the construction of building block for giant supramolecular biomimetic enzyme. To reveal the catalytic property of hydrophobic ADA-Te-ADA, the catalytic mechanism was investigated using PBS (phosphate buffer (pH 7.0. 50 mM))/methanol solvent mixture as assay solution. Itindicated that ADA-Te-ADA exhibited typical enzyme catalytic behavior by saturation kinetics measurement. Importantly, ADA-Te-ADA exhibited the typical solvent-dependent catalytic behavior. And the highest catalytic rate 4.29 µM x min-1 was obtained when the volume ratio of PBs: methanol was 5 : 5. Especially, the catalytic rates obtained based on various substrates proved that ADA-Te-ADA slightly displayed special substrate selectivity, which was the ideal catalytic characterization of building block for giant supramolecular biomimetic enzyme. The successfully synthesis of ADA-Te-ADA might highlight for the understanding of the catalytic mechanism of hydrophobic guest biomimetic glutathione peroxidase. And it also might provide the basement for the construction of giant supramolecular biomimetic enzyme.


Assuntos
Adamantano/síntese química , Biocatálise , Biomimética , Glutationa Peroxidase/síntese química , Adamantano/química , Domínio Catalítico , Glutationa Peroxidase/química , Cinética , Ressonância Magnética Nuclear Biomolecular , Solventes/química
8.
Bioorg Med Chem Lett ; 23(22): 6134-7, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24084160

RESUMO

A series of novel pyrimidone analogues have been designed and synthesized as HIV-1 integrase (IN) inhibitors. This study demonstrated that introducing a substituent in the N1-position of the pyrimidone scaffold does not significantly influence IN inhibitory activity. Molecular docking studies showed these compounds could occupy the IN active site and form pi-pi interactions with viral DNA nucleotides DC16 and DA17 to displace reactive viral DNA 3'OH and block intasome activity.


Assuntos
Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/farmacologia , HIV-1/enzimologia , Pirimidinonas/química , Pirimidinonas/farmacologia , Domínio Catalítico , DNA Viral/química , DNA Viral/metabolismo , Inibidores de Integrase de HIV/síntese química , HIV-1/química , HIV-1/efeitos dos fármacos , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Pirimidinonas/síntese química
9.
Chemosphere ; 319: 137979, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36736475

RESUMO

Nanoscale zero-valent iron (nZVI) has been widely used in the reductive removal of contaminants from water, yet it still fights against the inherent passive cover and the raise of medium pH. In this study, nZVI was supported onto a nitrogen-doped biochar (NBC) that was prepared by pyrolyzing shrimp shell for efficiently sequestrating aqueous selenite (Se(IV)). The resultant composite (NBC-nZVI) revealed a higher reactivity and electron utilization efficiency (EUE) than the bare nZVI in Se(IV) sequestration because of the positive charge, the buffering effect and the good conductivity of NBC. The kinetic rate and EUE of NBC-nZVI were increased by 143.4% and 15.3% compared to the bare nZVI, respectively, at initial pH of 3.0. The high removal capacity of 605.4 mg g-1 for NBC-nZVI was obtained at Se(IV) concentration of 1000 mg L-1, initial pH of 3.0, NBC-nZVI dosage of 1.0 g L-1 and contact time of 12 h. Moreover, NBC-nZVI exhibited a strong tolerance to solution pHs and coexisting compounds (e.g., humic acid) and could reduce the Se(IV) concentration from 5.0 mg L-1 to below the limit of drinking water (50 µg L-1) in real-world samples. This work exemplified a utilization of shrimp shell-derived NBC to simultaneously enhance the reactivity and EUE of nZVI for reductively removing contaminants.


Assuntos
Ferro , Poluentes Químicos da Água , Ferro/química , Ácido Selenioso/química , Elétrons , Poluentes Químicos da Água/análise , Água/química , Adsorção
10.
Int J Biol Macromol ; 253(Pt 7): 127458, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37844816

RESUMO

In this study, an amine-rich gel (ARAS) was prepared by chemically altering Acacia senegal (AS). ARAS acts as an adsorbent for selenium. Owing to the introduction of amino functional groups and a remarkable specific surface area (91.89 g/m2), ARAS shows maximum adsorption capacities at 75 and 130 mg g-1 for Se(IV) and Se(VI), respectively. The removal efficiency of ARAS is higher (ωSeIV = 98.2 % and ωSeVI = 98.6 %) at lower concentrations (CSeIV = 100 ppm and CSeVI = 95 ppm) and the adsorption equilibrium is achieved within 60 min. The adsorption process of Se (IV) and Se (VI) via ARAS is elucidated using the Quasi-Second-Order kinetic and Langmuir models. The enhanced adsorption capacity of the adsorbent could be attributed to the synergistic effects of electrostatic attraction, hydrogen bonding, and specific physicochemical properties. Thermodynamic studies reveal that the surface adsorption process is spontaneous and exothermic. Notably, ARAS maintains remarkable adsorption stability under a variety of solution conditions, including variable pH (4-11), NaCl concentrations (0-1 M), and the presence of organic solvents. It retains approximately 60 % of its initial adsorption capacity for Se(IV) and Se(VI) after three adsorption cycles. Therefore, ARAS with its cost-effectiveness and exceptional performance shows considerable potential for applications in water treatment.


Assuntos
Acacia , Selênio , Poluentes Químicos da Água , Selênio/química , Adsorção , Senegal , Poluentes Químicos da Água/química , Polissacarídeos , Aminas , Concentração de Íons de Hidrogênio , Cinética
11.
J Agric Food Chem ; 71(11): 4625-4637, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36892038

RESUMO

In this study, five novel Se-enriched antioxidant peptides (FLSeML, LSeMAAL, LASeMMVL, SeMLLAA, and LSeMAL) were purified and identified from Se-enriched Moringa oleifera (M. oleifera) seed protein hydrolysate. The five peptides showed excellent cellular antioxidant activity, with respective EC50 values of 0.291, 0.383, 0.662, 0.1, and 0.123 µg/mL. The five peptides (0.025 mg/mL) increased the cell viability from 78.72 to 90.71, 89.16, 93.92, 83.68, and 98.29%, respectively, effectively reducing reactive oxygen species accumulation and significantly increasing superoxide dismutase and catalase activities in damaged cells. Molecular docking results revealed that the five novel Se-enriched peptides interacted with the key amino acid of Keap1, thus directly blocking the interaction of Keap1-Nrf2 and activating the antioxidant stress response to enhance the ability of scavenging free radicals in vitro. In conclusion, Se-enriched M. oleifera seed peptides exhibited significant antioxidant activity and can be expected to find widespread use as a highly active natural functional food additive and ingredient.


Assuntos
Moringa oleifera , Selênio , Antioxidantes/química , Proteína 1 Associada a ECH Semelhante a Kelch , Moringa oleifera/química , Selênio/análise , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Fator 2 Relacionado a NF-E2/análise , Peptídeos/farmacologia , Peptídeos/análise , Sementes/química
12.
J Phys Chem B ; 126(9): 1933-1940, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35200022

RESUMO

Constructing an artificial cell wall (AFCW) based on the layer-by-layer assembly of polymer films to protect probiotics in harsh conditions is highly desirable. Early findings showed that encapsulating yeast cells by an AFCW improved the cell viability by 50% in antibiotic solution. However, the detailed molecular interaction mechanism remains unclear by experiments. Herein, two ciprofloxacin (CPFX) permeation models, including models 1 and 2 that were, respectively, composed of just the yeast cell membrane and the AFCW coating cell membrane, were investigated by molecular dynamics simulations. The free energy profiles delineating the permeation process of CPFX reveal that the permeation of CPFX through the cell membrane of model 2 is more difficult than through that of model 1. The analysis results show that the AFCW leads to two sharp increases in free energy barriers, amounting to 8.9 and 6.2 kcal/mol, thereby reducing the penetrating rate of CPFX into the cell membrane. Moreover, decomposition of the potentials of mean force into free energy components suggested that the electrostatic interactions of CPFX with the AFCW predominantly contributed to the high free energy barriers. The current results provide a good understanding of the protective mechanism of the self-assembled cell walls against CPFX and help to design other AFCWs.


Assuntos
Células Artificiais , Probióticos , Parede Celular/metabolismo , Ciprofloxacina/metabolismo , Saccharomyces cerevisiae
13.
RSC Adv ; 12(47): 30495-30500, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36337980

RESUMO

Solvents have been recognized as a significant factor for modulating the shuttle of rotaxanes and regulating their functions regarding molecular machines by a lot of published studies. The mechanism of the effects of solvents on the motion of crown ether/amino rotaxanes, however, remains unclear. In this work, a rotaxane, formed by dibenzo-24-crown-8 (C[8]) and a dumbbell-shaped axle with two positively charged amino groups, was investigated at the atom level. Two-dimensional free-energy landscapes characterizing the conformational change of C[8] and the shuttling motions in chloroform and water were mapped. The results indicated that the barriers in water were evidently lower than those in chloroform. By analyzing the trajectories, there was no obvious steric effect during shuttling. Instead, the main driving force of shuttling was verified from electrostatic interactions, especially strong hydrogen bonding interactions between the axle and water, which resulted in the fast shuttling rate of the rotaxane. All in all, the polarity and hydrogen bond-forming ability of solvents are the main factors in affecting the shuttling rate of a crown ether/amino rotaxane. In addition, C[8] would adopt S-shaped conformations during shuttling except for situating in the amino sites with C-shaped ones adopted due to π-π stacking interactions. The results of this research improve the comprehension of the solvent modulation ability for shuttling in crown ether-based rotaxanes and illustrate the effects of structural modifications on motions. These new insights are expected to serve the efficient design and construction of molecular machines.

14.
Int J Biol Macromol ; 220: 79-89, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35973482

RESUMO

Pig hair (PH), a keratinous waste, was modified by ammonium thioglycolate in a ball milling to promote its performance of Hg(II) sequestration. The ball milling broke the hydrophobic cuticle sheath and enhanced the reduction of disulfide bond, which increased the sulfydryl content of the modified PH (BTPH) from 0.07 to 11.05 µmol/g. BTPH exhibited a significantly higher capture capacity of Hg(II) (415.4 mg/g) than PH (3.1 mg/g), as well as the commercial activated carbon (219.7 mg/g), and persisted its performance over a wide range of solution pH. Meanwhile, BTPH with a distribution coefficient of 5.703 × 105 mL/g could selectively capture Hg(II) from the water with the coexisting metal ions such as Mg(II), Cd(II) and Pb(II). Moreover, the low-cost BTPH could reduce the Hg(II) from 1.0 mg/L to well below the limit of drinkable water (2 µg/L) in real-world samples. Density functional theory (DFT) calculations and state-of-the-art characterizations illustrated that the binding of Hg(II) to sulfydryl groups was the main adsorption mechanism. Notably, BTPH decreased the mercury content of water spinaches from 24.1 to 0.50 mg/kg and thereby significantly reduced the phytotoxicity of Hg(II). This work therefore provides a sustainable way to utilize keratinous wastes for the remediation of aqueous Hg(II).


Assuntos
Mercúrio , Poluentes Químicos da Água , Adsorção , Animais , Cádmio/química , Carvão Vegetal/química , Dissulfetos , Cabelo/química , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Lipoproteínas HDL , Mercúrio/química , Compostos de Sulfidrila/química , Suínos , Água , Poluentes Químicos da Água/química
15.
Genes (Basel) ; 13(8)2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35893031

RESUMO

Vulvar size and angle are meaningful traits in pig production. Sows with abnormal vulva generally show reproductive disorders. In order to excavate candidate loci and genes associated with pig's vulvar traits, 270 Suhuai pigs with vulvar phenotype were genotyped by a porcine single nucleotide polymorphisms (SNP) Chip. Then, Chip data were imputed using resequenced data of 30 Suhuai pigs as a reference panel. Next, we estimated the heritability and performed a genome-wide association study (GWAS) for vulvar traits. The heritabilities for the traits vulvar length (VL), vulvar width (VW) and vulvar angle (VA) in this pig population were 0.23, 0.32 and 0.22, respectively. GWAS based on Chip data identified nine significant SNPs on the Sus scrofa chromosomes (SSC) 2, 7, 9 and 13 for VL or VW. GWAS based on imputed data identified 11 new quantitative trait loci (QTL) on SSC1, 2, 7, 8, 9, 11, 13, 16 and 17 for VL or VW. The most significant QTL for VL on SSC2 were refined to a 3.48-3.97 Mb region using linkage disequilibrium and linkage analysis (LDLA). In this refined region, FGF19 and CCND1, involved in the development of the reproductive tract, cell growth and vulvar cancer, could be new candidate genes affecting VL. Our results provided potential genetic markers for the breeding of vulvar traits in pigs and deepened the understanding of the genetic mechanism of vulvar traits.


Assuntos
Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Sus scrofa , Animais , Feminino , Estudo de Associação Genômica Ampla/veterinária , Fenótipo , Sus scrofa/genética , Suínos/genética , Vulva
16.
Food Res Int ; 157: 111359, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761620

RESUMO

Natural organic selenium (Se) has multiple physiological health benefits and has become a hotspot of research in recent years. In this study, the Se-enriched antioxidant peptides were purified from Se-enriched oyster hydrolysate. Three novel Se-enriched antioxidant peptides LLVSeMY (685.2953 Da), MMDSeML (687.1875 Da) and VSeMDSeML (703.1599 Da) were identified from fraction F6-4, which all exhibited strong cellular antioxidant activity (CAA) with EC50 values of 0.739, 0.423, and 0.395 µg/mL, respectively. These three Se-enriched antioxidant peptides (0.025 mg/mL) could significantly enhanced cell viability to 84.60 ± 3.32% âˆ¼ 86.18 ± 1.36% compared with the AAPH injury group (75.99 ± 0.79%), and the cytoprotective effects were even better than that of GSH (80.47 ± 2.78%). Moreover, these three Se-enriched peptides also significantly protected HepG2 cells from AAPH-induced oxidative injury by inhibiting ROS production and enhancing the activities of antioxidant enzymes. The molecular docking results showed that these three Se-enriched peptides can form stable hydrogen and hydrophobic bonds with key amino acid residues of Keap1 protein, thereby potentially regulating the Keap1-Nrf2 pathway. In conclusion, the three novel Se-enriched oyster antioxidant peptides are expected to be used in medicine or functional food, providing a new theoretical basis for the high-value utilization of natural organic Se.


Assuntos
Ostreidae , Selênio , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Ostreidae/metabolismo , Peptídeos/química , Selênio/metabolismo , Selênio/farmacologia
17.
Polymers (Basel) ; 13(24)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34960860

RESUMO

Selenium-functionalized starch (Se-starch80) is one of the main functional foods used for selenium supplementation. In traditional agriculture, Se-starch has some deficiencies such as long growth cycle and unstable selenium content that prevent its antioxidant performance. In this study, Se-starch was prepared by the nucleophilic addition between NaSeH and carbon-carbon double bond of octenyl succinic anhydride waxy corn starch ester (OSA starch). Some techniques such as 1HNMR, XPS, SEM-EDS, XRD and FT-IR were used to characterize the relevant samples and the results showed that the modification did not destroy the starch framework significantly and the catalytic center (negative divalent selenium) was anchored on the starch framework. The intensive distribution of catalytic center on the starch surface and the hydrophobic microenvironments derived from the OSA chains furnished the Se-starch80 with a high GPx-like catalytic activity (initial reaction rate = 3.64 µM/min). This value was about 1.5 × 105 times higher than that of a typical small-molecule GPx mimic (PhSeSePh). In addition, the Se-starch80, without any cytotoxicity, showed a saturated kinetic catalytic behavior that is similar to a typical enzyme. This work exemplifies a biodegradable selenium-functionalized polymer platform for the high-performing GPx mimic.

18.
Int J Biol Macromol ; 189: 242-250, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34425120

RESUMO

In this work, a combined mechanical activation and FeCl3 (MA + FeCl3) method was applied to pretreat chitin to enhance the degree of hydrothermal carbonization. MA + FeCl3 pretreatment significantly disrupt the crystalline region of chitin and Fe3+ entered into the molecular chain, resulting in the destruction of the stable structure of chitin. The chemical and structural properties of hydrochars were characterized by EA, SEM, FTIR, XRD, XPS, 13C solid state NMR, and N2 adsorption-desorption analyses. The results showed that the H/C and O/C atomic ratios of HC-MAFCT/230 (the hydrochar derived from MA + FeCl3 pretreated chitin with hydrothermal reaction temperature of 230 °C) were 0.96 and 0.34, respectively. Van Krevelen diagram indicated that the hydrothermal carbonization of chitin underwent a series of reactions such as dehydration, decarboxylation, and aromatization. HC-MAFCT/230 had abundant oxygen- and nitrogen-containing functional groups. HC-MAFCT/230 exhibited a porous structure, with the specific surface area of 128 m2 g-1, which was a promising carbon material.


Assuntos
Carbono/química , Quitina/química , Cloretos/química , Compostos Férricos/química , Fenômenos Mecânicos , Temperatura , Água/química , Adsorção , Configuração de Carboidratos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Carvão Vegetal/química , Nitrogênio , Espectroscopia Fotoeletrônica , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
19.
RSC Adv ; 11(63): 39758-39767, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-35494106

RESUMO

The preparation of antioxidant starch with the activity of glutathione peroxidase (GPx) for scavenging free radicals can not only enrich the types of modified starch but also alternate native GPx to overcome its drawbacks. In this work, an antioxidant cassava starch (AO-ca-starch) was prepared by the sequential esterification and selenylation of cassava starch. The process was optimized based on the selenium content. Various characterizations for the AO-ca-starch indicated that the catalytic center of GPx, the selenium, was anchored on the starch. The catalytic activity of AO-ca-starch, a starch-based biomimetic GPx, was about 4.95 × 105 times higher than that of the typical artificial selenoenzyme (diphenyl diselenide, PhSeSePh), and it exhibited a typical saturation kinetic catalytic behavior. The surface changes of the starch during the modification were conducive to the formation of hydrophobic microenvironments, which played an important role in the catalytic reaction of biomimetic GPx due to the binding of the hydrophobic substrates. The match of the catalytic center and the hydrophobic microenvironments was the key factor for maintaining the high catalytic activity of AO-ca-starch. Without cytotoxicity, AO-ca-starch exemplified a new and promising modified starch as a selenium-enriched functional food and antioxidant drug.

20.
Bioorg Chem ; 38(4): 159-64, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20363012

RESUMO

For constructing a bifunctional antioxidative enzyme with both superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, a supramolecular artificial enzyme was successfully constructed by the self-assembly of the Mn(III)meso-tetra[1-(1-adamantyl methyl ketone)-4-pyridyl] porphyrin (MnTPyP-M-Ad) and cyclodextrin-based telluronic acid (2-CD-TeO(3)H) through host-guest interaction in aqueous solution. The self-assembly of the adamantyl moieties of Mn(III) porphyrin and the beta-CD cavities of 2-CD-TeO(3)H was demonstrated by the NMR spectra. In this supramolecular enzyme model, the Mn(III) porphyrin center acted as an efficient active site of SOD and tellurol moiety endowed GPx activity. The SOD-like activity (IC(50)) of the new catalyst was found to be 0.116 microM and equals to 2.56% of the activity of the native SOD. Besides this, supramolecular enzyme model also showed a high GPx activity, and a remarkable rate enhancement of 27-fold compared to the well-known GPx mimic ebselen was observed. More importantly, the supramolecular artificial enzyme showed good thermal stability.


Assuntos
Adamantano/química , Glutationa Peroxidase/química , Porfirinas/química , Superóxido Dismutase/química , beta-Ciclodextrinas/química , Adamantano/síntese química , Adamantano/metabolismo , Domínio Catalítico , Glutationa Peroxidase/síntese química , Glutationa Peroxidase/metabolismo , Cinética , Manganês/química , Manganês/metabolismo , Porfirinas/síntese química , Porfirinas/metabolismo , Superóxido Dismutase/síntese química , Superóxido Dismutase/metabolismo , beta-Ciclodextrinas/síntese química , beta-Ciclodextrinas/metabolismo
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