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1.
Int J Biol Macromol ; 253(Pt 7): 127458, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37844816

RESUMEN

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.


Asunto(s)
Acacia , Selenio , Contaminantes Químicos del Agua , Selenio/química , Adsorción , Senegal , Contaminantes Químicos del Agua/química , Polisacáridos , Aminas , Concentración de Iones de Hidrógeno , Cinética
2.
Anim Genet ; 54(4): 435-445, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36911996

RESUMEN

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.


Asunto(s)
Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Animales , Porcinos/genética , Estudio de Asociación del Genoma Completo/veterinaria , Teorema de Bayes , Genotipo , Fenotipo , Costillas , Polimorfismo de Nucleótido Simple , Sus scrofa/genética
3.
J Agric Food Chem ; 71(11): 4625-4637, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36892038

RESUMEN

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.


Asunto(s)
Moringa oleifera , Selenio , Antioxidantes/química , Proteína 1 Asociada A ECH Tipo Kelch , Moringa oleifera/química , Selenio/análisis , Simulación del Acoplamiento Molecular , Extractos Vegetales/química , Factor 2 Relacionado con NF-E2/análisis , Péptidos/farmacología , Péptidos/análisis , Semillas/química
4.
Chemosphere ; 319: 137979, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36736475

RESUMEN

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.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Hierro/química , Ácido Selenioso/química , Electrones , Contaminantes Químicos del Agua/análisis , Agua/química , Adsorción
5.
RSC Adv ; 12(47): 30495-30500, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36337980

RESUMEN

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.

6.
Int J Biol Macromol ; 220: 79-89, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35973482

RESUMEN

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).


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Adsorción , Animales , Cadmio/química , Carbón Orgánico/química , Disulfuros , Cabello/química , Concentración de Iones de Hidrógeno , Cinética , Plomo , Lipoproteínas HDL , Mercurio/química , Compuestos de Sulfhidrilo/química , Porcinos , Agua , Contaminantes Químicos del Agua/química
7.
Genes (Basel) ; 13(8)2022 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-35893031

RESUMEN

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.


Asunto(s)
Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Sus scrofa , Animales , Femenino , Estudio de Asociación del Genoma Completo/veterinaria , Fenotipo , Sus scrofa/genética , Porcinos/genética , Vulva
8.
Food Res Int ; 157: 111359, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35761620

RESUMEN

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.


Asunto(s)
Ostreidae , Selenio , Animales , Antioxidantes/química , Antioxidantes/farmacología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Simulación del Acoplamiento Molecular , Factor 2 Relacionado con NF-E2/metabolismo , Ostreidae/metabolismo , Péptidos/química , Selenio/metabolismo , Selenio/farmacología
9.
J Phys Chem B ; 126(9): 1933-1940, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200022

RESUMEN

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.


Asunto(s)
Células Artificiales , Probióticos , Pared Celular/metabolismo , Ciprofloxacina/metabolismo , Saccharomyces cerevisiae
10.
Polymers (Basel) ; 13(24)2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34960860

RESUMEN

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.

11.
Int J Biol Macromol ; 189: 242-250, 2021 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-34425120

RESUMEN

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.


Asunto(s)
Carbono/química , Quitina/química , Cloruros/química , Compuestos Férricos/química , Fenómenos Mecánicos , Temperatura , Agua/química , Adsorción , Conformación de Carbohidratos , Espectroscopía de Resonancia Magnética con Carbono-13 , Carbón Orgánico/química , Nitrógeno , Espectroscopía de Fotoelectrones , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
12.
RSC Adv ; 11(63): 39758-39767, 2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-35494106

RESUMEN

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.

13.
Macromol Biosci ; 20(12): e2000185, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32896072

RESUMEN

The pollution of antibiotics in aquaculture environment is increasingly serious, and excessive antibiotics will kill the probiotics in aquaculture feed. How to improve the viability of probiotics in the antibiotics-contaminated environment is of significance. In this study, a new strategy for protecting Saccharomyces cerevisiae cells in situ against antibiotics is constructed based on cell surface engineering technology by putting on wearable protective layers for cells. The protective layer is constructed around cellular surface via the self-assembly of coacervate microdroplets that consist of carboxymethyl chitosan and carboxyl dextran. Without affecting the cell viability, the protective layer can grasp ciprofloxacin and decrease the contact of ciprofloxacin to cells and consequently improve the survival rate of cells when exposing to ciprofloxacin. This work highlights a facile strategy to establish removable artificial cell wall by biodegradable polysaccharides for improving the productivity of probiotics in antibiotic environments.


Asunto(s)
Antibacterianos/efectos adversos , Pared Celular/efectos de los fármacos , Probióticos/química , Antibacterianos/química , Acuicultura , Supervivencia Celular/efectos de los fármacos , Quitosano/análogos & derivados , Quitosano/química , Ciprofloxacina/efectos adversos , Ciprofloxacina/química , Contaminación Ambiental/efectos adversos , Humanos
14.
Water Sci Technol ; 82(3): 492-502, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32960794

RESUMEN

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).


Asunto(s)
Quitina , Contaminantes Químicos del Agua/análisis , Adsorción , Cromo , Cinética , Fenilendiaminas , Espectroscopía Infrarroja por Transformada de Fourier
15.
Front Genet ; 11: 591, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32582299

RESUMEN

Chinese indigenous pig breeds in the Taihu Lake (TL) region of Eastern China are well documented by their exceptional prolificacy. There are seven breeds in this region including Meishan (MS), Erhualian (EHL), Jiaxing Black (JXB), Fengjing (FJ), Shawutou (SWT), Mi (MI), and Hongdenglong (HDL). At present, these breeds are facing a great threat of population decline, inbreeding depression and lineage admixture since Western commercial pigs have dominated in Chinese pig industry. To provide better conservation strategies and identify candidate genes under selection for these breeds, we explored genome-wide single nucleotide polymorphism (SNP) markers to uncover genetic variability and relatedness, population structure, historical admixture and genomic signature of selection of 440 pigs representing the most comprehensive lineages of these breeds in TL region in a context of 1228 pigs from 45 Eurasian breeds. We showed that these breeds were more closely related to each other as compared to other Eurasian breeds, defining one of the main ancestral lineages of Chinese indigenous pigs. These breeds can be divided into two subgroups, one including JXB and FJ, and the other comprising of EHL, MI, HDL, MS, and SWT. In addition, HDL was highly inbred whereas EHL and MS had more abundant genetic diversity owing to their multiple conservation populations. Moreover, we identified a list of candidate genes under selection for body size and prolificacy. Our results would benefit the conservation of these valuable breeds and improve our understanding of the genetic mechanisms of body size and fecundity in pigs.

16.
Food Chem ; 321: 126702, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32240917

RESUMEN

A new amino-modified Scholl-coupling mesoporous polymer (NH2@SMPA)-online solid-phase extraction method, coupled with high-performance liquid chromatography (online SPE-HPLC) was established for the analysis of six plant growth regulators (PGRs) in bean sprouts. NH2@SMPA was synthesized by acid-catalyzed deacetylation of acetylamino-Scholl-coupling mesoporous polymer (SMPA). The diversity of functional groups, such as aromatic, acetylamino, and NH2, was conducive to multiple binding interactions between NH2@SMPA and PGRs. NH2@SMPA exhibited superior extraction capability for PGRs, compared with SMPA and commercial adsorbents. The extraction conditions, including loading solvent, pH of loading solution, eluting solvent, and flow rates of loading and elution, were optimized. Under the optimized conditions, wide linear ranges (0.01-500 µg kg-1) and low detection limits (2.34-20.2 ng kg-1) were obtained. The recoveries were satisfactory, i.e., 86.0% to 109% with relative standard deviations ≤9.8% (n = 3). Finally, the online SPE-HPLC method was successfully used for determination of PGRs in bean sprouts.


Asunto(s)
Polímeros/química , Extracción en Fase Sólida , Aminación , Cromatografía Líquida de Alta Presión/métodos , Límite de Detección , Reguladores del Crecimiento de las Plantas/análisis , Polímeros/análisis , Porosidad , Extracción en Fase Sólida/métodos
17.
Int J Biol Macromol ; 148: 802-810, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31972192

RESUMEN

As a promising candidate of Cr(VI) decontamination, cellulose is limited in the Cr(VI) uptake due to its poor accessibility. Herein, We describe the synthesis of a novel cellulose-based adsorbent (PQC, where P and QC designate the polyethylenimine and quaternized cellulose, respectively) with functional groups of quaternary ammonium and amino for enhanced capture of Cr(VI) from water. For preparing PQC, cellulose is first quaternized homogeneously, followed by grafting and/or cross-linking with polyethylenimine in the presence of epichlorohydrin. The PQC follows the Langmuir isotherm and presents a maximum Cr(VI) uptake capacity of 490.3 mg/g at 30 °C and initial pH about 2.0, much higher than many other reported cellulose-based adsorbents. The adsorption of PQC is spontaneous and endothermic, which follows the pseudo-second-order kinetic model and achieves the equilibrium after contacting about 50 min. Furthermore, the PQC, with favorable reusability, can work well in a high coexisting anion concentration. These excellent absorption performances are attributed to its physicochemical properties such as the robust porous structure and high density of functional groups including quaternary ammonium, amino and hydroxyl, which improve the availability to capture or reduce Cr(VI). This work demonstrates the significant potential of cellulose-based adsorbent for remediating aqueous Cr(VI).


Asunto(s)
Compuestos de Amonio/química , Celulosa/química , Cromo/química , Agua/química , Adsorción , Aniones/química , Epiclorhidrina/química , Concentración de Iones de Hidrógeno , Cinética , Polietileneimina/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
18.
J Hazard Mater ; 380: 120892, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31325699

RESUMEN

Alkylation reaction catalyzed by concentrated H2SO4 generates hazardous waste H2SO4 containing a large amount of organic pollutants. This study focused on effective utilization and treatment of the waste H2SO4 for simultaneous consumption of H2SO4 and deep oxidative degradation of the organics. The waste H2SO4 could completely react with magnesium oxide ore to prepare crude MgSO4 solution, and the organic pollutants in the solution were deeply degraded and mainly mineralized to H2O and CO2 with H2O2 as oxidant and sugarcane bagasse citrate (SBC), a kind of lignocellulose ester, as catalyst. The total amount of acidic groups of SBC significantly affected its catalytic activity, attributing to that these oxygen-containing functional groups adsorbed and immobilized metal ions on SBC to form catalytic active sites, which could activate and catalyze H2O2 to generate •OH and HO2• radicals for effective degradation of the organics. The resulting purified MgSO4 solution with color removal of 93.71% and total organic carbon removal of 85.89% under optimum catalytic reaction conditions was used to produce qualified MgSO4∙7H2O product. These results highlighted the feasibility of using lignocellulose ester as effective catalyst for deep oxidative degradation of hazardous organic pollutants.


Asunto(s)
Contaminantes Ambientales/química , Sustancias Peligrosas/química , Lignina/química , Compuestos Orgánicos/química , Ácidos Sulfúricos/química , Alquilación , Catálisis , Calor , Cinética , Oxidación-Reducción
19.
RSC Adv ; 9(28): 16130-16135, 2019 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35521406

RESUMEN

In the presence of the amino acid histidine, an inorganic-organic hybrid metal sulfite, Zn2(SO3)2(C6N3O2H9)2·H2O (1), has been prepared under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals that 1 shows a 2D layer framework built up from a classical second building unit (S4R), and bridged histidine molecule. Notably, it is the first report of a metal sulfite in the presence of an amino acid molecule. A 1D H-bonding array can be constructed by the H-bonding interaction between histidine molecules and sulfite groups. Moreover, a new function of metal sulfite for proton conduction was investigated by alternating-current impedance analysis. The results demonstrate that compound 1 shows a high proton conductivity of approximately 10-3 S cm-1 at 348 K and 98% relative humidity.

20.
RSC Adv ; 9(49): 28814-28822, 2019 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-35529614

RESUMEN

Excessive reactive oxygen free radicals (ROS) are the main cause of various oxidative diseases. It is of great significance to develop antioxidant drugs that can intelligently regulate free radical concentrations. The biomimetic simulation of glutathione peroxidase (GPx) can provide an important theoretical basis for the development of antioxidant drugs. In order to explore a simple and efficient strategy for constructing biomimetic GPx, a microgel biomimetic GPx (PNTegel) with temperature responsive catalytic activity was prepared by a one-pot synthesis method. The PNTegel, with typical enzymatic catalytic characteristics, exhibited a maximum catalytic activity at 37 °C (υ 0 = 11.51 mM min-1). The investigation of the catalytic mechanism of PNTegel suggested that the binding of different hydrophobic substrates to PNTegel was altered by the change of hydrophobicity of poly(N-isopropylacrylamide) (PNIPAM) in the microgel scaffold of PNTegel during the temperature response process. The change of hydrophobicity was the main factor for regulating the catalytic activity of PNTegel, which resulted in a temperature responsive catalytic behavior of PNTegel. This new strategy for the simple and efficient construction of biomimetic GPx by a one-pot method provides important theoretical support for exploring the preparation of highly effective antioxidant drugs.

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