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1.
Chemosphere ; 362: 142732, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38950746

RESUMO

Industrial wastewater containing heavy metal Cr(VI) seriously affects the health of organisms and may even lead to cancer. Developing efficient adsorbents that can quickly separate heavy metals is crucial for treating wastewater. In this study, magnetic multiwalled carbon nanotubes (MMWCNTs) with moderate particle size and abundant surface active sites were prepared by coating multiwalled carbon nanotubes with magnetic nanoparticles. The results of FTIR, XRD, TG, VSM, BET, and EDS showed MWCNTs completely encapsulated on the surface of the magnetic nanoparticles, with a particle size of approximately 30 nm. Oxygenated groups provided abundant surface active sites and formed numerous mesopores. The response surface methodology was used to optimize the adsorbent dose, adsorption contact time and adsorption temperature, and the removal rate of Cr(VI) was more than 95%. The quasi-second order kinetics and Freundlich adsorption isotherm model explained the adsorption process to Cr(VI). MMWCNTs interacted with Cr(VI) through electrostatic attraction, reduction reactions, complexation, and other means. The extensive hydrogen bonding of the green solvent deep eutectic solvent (DES) was employed to desorb the MMWCNTs and desorption rate exceed 90%. Even after five adsorption-regeneration cycles, the adsorbent maintained a high capacity. In conclusion, these novel MMWCNTs, as efficient adsorbents paired with DES desorption, hold broad potential for application in the treatment of Cr(VI)-contaminated wastewater.

2.
Brain Sci ; 13(11)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-38002477

RESUMO

The aim of this study was to investigate the inner link between the small-world brain network and inhibitory control. Functional near-infrared spectroscopy (fNIRS) was used to construct a neurofeedback (NF) training system and regulate the frontal small-world brain network. The small-world network downregulation group (DOWN, n = 17) and the small-world network upregulation group (UP, n = 17) received five days of fNIRS-NF training and performed the color-word Stroop task before and after training. The behavioral and functional brain network topology results of both groups were analyzed by a repeated-measures analysis of variance (ANOVA), which showed that the upregulation training helped to improve inhibitory control. The upregulated small-world brain network exhibits an increase in the brain network regularization, links widely dispersed brain resources, and reduces the lateralization of brain functional networks between hemispheres. This suggests an inherent correlation between small-world functional brain networks and inhibitory control; moreover, dynamic optimization under cost efficiency trade-offs provides a neural basis for inhibitory control. Inhibitory control is not a simple function of a single brain region or connectivity but rather an emergent property of a broader network.

3.
Carbohydr Polym ; 321: 121295, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739528

RESUMO

To accurately determine flavonoids (rutin, quercetin or kaempferol), it is necessary to extract them from complex matrices. The ultrasound-assisted magnetic dispersion microsolid phase extraction technique has been predominantly used for separation and enrichment of the target analytes. The combination of magnetic chitosan nanoparticles and a deep eutectic supramolecular solvent (DESP) is likely to enhance the efficiency of flavonoid extraction from food. In this study, adsorbents were prepared by modifying chitosan with magnetic nanoparticles, and the eluent was a DESP derived from ß-cyclodextrin and an organic acid. The successful preparation of these materials was confirmed by FTIR, XRD, FE-SEM and 1H NMR. The extraction recovery rates exceeded 93 %, with limits of detection and quantitation ranging from 0.9 to 2.4 µg/L and 2.7 to 7.2 µg/L, respectively, and the flavonoid clearance rates for ABTS and DPPH radicals reached 100 %. Therefore, the integration of magnetic chitosan nanoparticles with the DESP provides a new and efficient method for the extraction of flavonoids while also presenting a potential application of the DESP in separations.


Assuntos
Quitosana , Nanopartículas de Magnetita , beta-Ciclodextrinas , Flavonoides , Quercetina
4.
Antioxidants (Basel) ; 12(7)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37507927

RESUMO

High-quality eggs are essential for the sustainability of commercial aquaculture production. Melatonin is a potent candidate for regulating the growth and maturation of oocytes. Therefore, research on the effect of melatonin on marine fish oocytes in vitro has been conducted. The present study successfully established a culture system of turbot (Scophthalmus maximus) oocytes in vitro and investigated the effect of melatonin on oocyte meiotic maturation, antioxidant capacity, and the expression of apoptosis-related genes. The cultures showed that turbot Scophthalmus maximus late-vitellogenic denuded oocytes, with diameters of 0.5-0.7 mm, had a low spontaneous maturation rate and exhibited a sensitive response to 17α, 20ß-dihydroxyprogesterone (DHP) treatment in vitro. Melatonin increased by four times the rate of oocyte germinal vesicle breakdown (GVBD) in a concentration- and time-dependent manner. The mRNA of melatonin receptor 1 (mtnr1) was significantly upregulated in the oocyte and follicle after treatment with melatonin (4.3 × 10-9 M) for 24 h in vitro, whereas melatonin receptor 2 (mtnr2) and melatonin receptor 3 (mtnr3) remained unchanged. In addition, melatonin significantly increased the activities of catalase, glutathione peroxidase, and superoxide dismutase, as well as the levels of glutathione, while decreasing the levels of malondialdehyde and reactive oxygen species (ROS) levels in turbot oocytes and follicles cultures in vitro. p53, caspase3, and bax mRNAs were significantly downregulated in oocytes and follicles, whereas bcl2 mRNAs were significantly upregulated. In conclusion, the use of turbot late-vitellogenesis oocytes (0.5-0.7 mm) is suitable for establishing a culture system in vitro. Melatonin promotes oocyte meiotic maturation and antioxidative capacity and inhibits apoptosis via the p53-bax-bcl2 and caspase-dependent pathways, which have important potential to improve the maturation and quality of oocytes.

5.
Chemosphere ; 338: 139508, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37459925

RESUMO

A combination of magnetic κ-carrageenan nanoparticles and deep eutectic supramolecular solvents used for extraction of catechol from water was evaluated by the magnetic dispersion solid phase extraction method. The magnetic κ-carrageenan nanoparticles (KC@Fe3O4MNPs) and the deep eutectic supramolecular solvent (DESP) were characterised by 1H NMR, FT-IR, XRD, SEM, VSM, TG, and BET. The adsorption kinetics, adsorption isothermal model, adsorption thermodynamics and effects of pH and salt concentration were investigated. Additionally, the factors used in the desorption process, such as the type, dosage, concentration and time, were analysed. Under the optimised conditions, the analytes were linear over the range 5-5000 ng mL-1, with a correlation coefficient greater than 0.999 and detection and quantitation limits of 1.6 and 4.7 ng mL-1, respectively. The procedure was successfully applied to determinations of the analytes of interest in spiked water samples with relative average recoveries ranging from 94.3% to 101.5%. These results indicated that the combination of functionalized magnetic nanoparticles and DESP had high specificity and extraction efficiency for catechol and will be a feasible alternative to conventional analyses of organic phenolic pollutants in water.


Assuntos
Fenômenos Magnéticos , Água , Água/química , Carragenina , Espectroscopia de Infravermelho com Transformada de Fourier , Solventes/química , Catecóis , Extração em Fase Sólida/métodos , Limite de Detecção
6.
Environ Res ; 236(Pt 2): 116778, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37517482

RESUMO

The fabrication of an adsorbent with excellent performance has been a focus of attention because of the toxicity, mutagenicity and carcinogenicity of methyl orange (MO)-containing wastewater discharged from the textile, tannery and pharmaceutical industries. In this study, chitosan (CS) membranes were modified with a deep eutectic supramolecular polymer (DESP), and adsorbent membranes with porous structures were prepared with polyethylene glycol (PEG). Microstructural characterization of the CS-DESP-PEG composite membranes with FT-IR, XRD and SEM showed that the membranes had amorphous crystalline structures and that hydrogen bonding interactions weakened the crystallinity and formed loose porous structures. Optimization of the chitosan to ß-cyclodextrin ratio, pH, PEG proportion, MO concentration and adsorbent dose significantly improved the adsorption efficiencies of the membranes. The adsorption behaviours of the membranes were fit with pseudo-second-order adsorption kinetics and the Freundlich adsorption isotherm model. Regeneration experiments showed that the membranes were reusable multiple times and maintained good adsorption capacities.


Assuntos
Quitosana , Poluentes Químicos da Água , Quitosana/química , Adsorção , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
7.
Artigo em Inglês | MEDLINE | ID: mdl-37229966

RESUMO

Hypoxia has become a common problem for aquatic organisms due to the interaction of global climate change and human activity. Black rockfish inhabits rocky reefs in waters of Japan, Korea and China, whereas the limited hypoxia tolerance leads to mass mortality and great economic loss. In this study, high-throughput RNA-seq for transcriptomic analysis was used to investigate the hepatic response in black rockfish under hypoxia (critical oxygen tension, Pcrit; loss of equilibrium, LOE) and reoxygenation (recover normal dissolved oxygen 24 h, R24) to explore the mechanisms underlying hypoxia tolerance and adaptation. A total of 573,040,410 clean reads and 299 differentially expressed genes (DEGs) in total were obtained during hypoxia and reoxygenation. GO annotation and Kyoto Encyclopedia of Genes and Genomes analysis demonstrated that the DEGs are mainly enriched in the biochemical metabolic pathways and HIF-1 signaling pathways. Transcriptomic analysis also identified 18 DEGs associated with HIF-1 signaling pathway (hif1α, tf, epo, hmox, gult1, mknk2, ldha, pfkfb3, hkdc, aldoa) and biological process (hif2α, apoeb, bcl6, mr1, errfi1, slc38a4, igfbp1a, ap4m1) as further validated by quantitative real-time PCR. Moreover, hif1α was positively or negatively correlated with glucose (ldha, pfkfb3, hkdc, aldoa) and lipid (apoeb) metabolism-related genes. The mRNA level of hif1α was significantly up-regulated under acute hypoxia stress and obtained the higher values than hif2α. Meanwhile, hif1α recognized the hypoxia response element located in the promoter of ldha and directly bound to the promoter to transactivate ldha expression. These results indicated that black rockfish may mainly utilize glycolysis to maintain homeostasis, and hif1α facilities hypoxia tolerance by modulating ldha expression.


Assuntos
Perciformes , Transcriptoma , Humanos , Animais , Hipóxia/genética , Perciformes/genética , Perciformes/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , China
8.
Aquat Toxicol ; 258: 106502, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36965427

RESUMO

Dissolved oxygen concentrations both in the open ocean and coast have been declining due to the interaction of global climate change and human activity. Fish have evolved different adaptative strategies to cope with possibly damage induced by hypoxic environments. Black rockfish as important economic fish widely reared in the offshore sea cage, whereas related physiological response subject to hypoxia stress remained unclear. In this study, hepatic anti-oxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GSH-Px]), aminotransferase (AST) and alanine aminotransferase (ALT) activities, lipid peroxidation (LPO), malondialdehyde (MDA) and glutathione (GSH) content, immunological parameters and the expression of apoptosis (bax, bcl2, p53, caspase3, xiap) and immune-related genes (c3, il-1ß, ccl25, saa, hap, isg15) of black rockfish were determined during hypoxia and reoxygenation to illustrate the underlying defense response mechanisms. Results showed that hypoxia stress remarkably increased hepatic LPO and MDA content, AST and ALT activity and proportion of pyknotic nucleus. Hepatic SOD, CAT and GSH-Px activity manifested similar results, whereas GSH levels significantly decreased under hypoxia stress. The apoptosis rate of hepatocyte increased during hypoxia stress and reoxygenation. Meanwhile, p53, caspase3, bax and xiap mRNAs and bax/bcl2 rations were significantly up-regulated under hypoxia stress. However, bcl2 mRNA was significantly down-regulated. Interestingly, hypoxia stress significantly increased NBT-positive cell percent, phagocytic index, respiratory burst and ACH50 activity, and lysozyme activity. The mRNA levels of c3, ilß, ccl25, saa, hap and isg15 were significantly up-regulated in the liver, spleen and head-kidney under hypoxia stress. The above parameters recovered to normal status after reoxygenation for 24 h Thus, hypoxia stress impairs hepatic antioxidant capacity, induces oxidative damage and apoptosis via the xiap-p53-bax-bcl2 and the caspase-dependent pathways, but enhances host immunity by regulating nonspecific immune indices and related genes expression to maintain homeostasis in black rockfish. These findings will help fully understand the hypoxia tolerance mechanisms of black rockfish and provide more data for offshore open ocean farming.


Assuntos
Perciformes , Poluentes Químicos da Água , Animais , Humanos , Antioxidantes/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Poluentes Químicos da Água/toxicidade , Fígado/metabolismo , Apoptose , Glutationa/metabolismo , Superóxido Dismutase/metabolismo , Perciformes/metabolismo , Expressão Gênica , RNA Mensageiro/metabolismo , Imunidade
9.
Ultrason Sonochem ; 92: 106283, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36610241

RESUMO

Ultrasound and deep eutectic supramolecular polymers (DESP) is a novel combination of green extraction method for phytochemicals. In this study, a new type of green extractant was developed: DESP. It is a derivative of deep eutectic solvent (DES) and was prepared by supramolecular polymer unit ß-cyclodextrin (ß-CD) as hydrogen bond acceptor (HBA) and organic acid as hydrogen bond donor (HBD). The current work focuses on the use of ultrasonic-assisted (UAE) DESP extraction of polyphenolic compounds (PCs) from bayberry. The experimental results showed that DESP synthesized with ß-CD and lactic acid (LA) in a ratio of 1:1 (w/w %) had the best extraction effect. And by using a three-level factor experiment and the response surface method, the predicted TPC content is very close to the actual content (28.85 ± 1.27 mg GAE/g). The DESP extract including PCs were further used as plasticizer for chitosan (CS) to prepare highly active green biofilms (DESP-CS). It is possible to reduce the tedious procedures for separating biologically active substances from DESP. The experiment proved that the prepared films have good mechanical properties, plastic deformation resistance, thermal stability and antioxidant activity.


Assuntos
Myrica , Polifenóis , Polifenóis/química , Ultrassom , Solventes/química , Polímeros
10.
Food Chem ; 410: 135338, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36621335

RESUMO

A magnetic dispersive micro-solid phase extraction technique (CS@Fe3O4-MD-µSPE-DESP) based on magnetic chitosan nanoparticles and a deep eutectic supramolecular solvent was developed and applied to determinations of four phenolic compounds in food samples. To prevent environmental pollution and the introduction of toxic substances, deep eutectic supramolecular solvents (DESPs), which exhibited greater desorption capacities than conventional organic solvents and deep eutectic solvents, were used as novel green eluents for the first time. Some important parameters were screened by the Plackett-Burman method and then further optimized with response surface methodology (RSM). Under the optimal conditions, the proposed method showed excellent methodological indices with linearity over the range 0.1-200.0 µg·mL-1, R2 > 0.9988, extraction recoveries above 94.8 %, and precision (RSD%) below 2.9 %. The established method finishes the process of adsorption and desorption in approximately 3 min and enhances the efficiency for determination of phenolic compounds.


Assuntos
Quitosana , Microextração em Fase Líquida , Solventes , Extração em Fase Sólida/métodos , Magnetismo , Fenômenos Magnéticos , Microextração em Fase Líquida/métodos
11.
Fish Physiol Biochem ; 47(4): 1133-1147, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34059979

RESUMO

Hypoxia has gradually become common in aquatic ecosystems and imposes a significant challenge for fish farming. The loss of equilibrium (LOE), 50% lethal time (LT50), plasma cortisol, glucose, red blood cells (RBC), hemoglobin (Hb), gill histological alteration, and related parameters (lamellar length [SLL] and width [SLW], interlamellar distance [ID], basal epithelial thickness [BET], lamellar surface area [LA], and gill surface area [GSA]); respiratory rate; the proportion of the secondary lamellae available for gas exchange (PAGE); and hypoxia-inducible factor (hif-1α, hif-2α) mRNA expression were determined during progressive hypoxia and reoxygenation (R-0, R-12, R-24 h) to illustrate the underlying physiological response mechanisms in black rockfish Sebastes schlegelii. Results showed that the DO concentration significantly decreased during progressive hypoxia, while DO at LOE and LT50 were 2.42 ± 0.10 mg L-1 and 1.67 ± 0.38 mg L-1, respectively. Cortisol and glucose were significantly increased at LOE and LT50, with the highest levels observed at LT50, and then gradually recovered to normal within reoxygenation 24 h. RBC number and Hb results were like those of glucose. Hypoxia stress resulted in lamellar clubbing, hypertrophy, and hyperplasia. Respiratory frequency significantly increased at LOE and decreased at LT50. Lamellar perimeters, SLL, ID, LA, GSA, and PAGE, significantly increased at LOE and LT50, with the highest values observed at LT50. However, SLW and BET significantly decreased at LOE, LT50, and R-0. These parameters recovered to nearly normal levels at R-24 h. hif-1α mRNAs in gill and liver were significantly upregulated at LOE and LT50, and recovery to normal after reoxygenation 24 h. hif-2α mRNAs in gill was similar to that of hif-1α, whereas hepatic hif-2α mRNAs remained unchanged during hypoxia-reoxygenation. These results indicated that progressive hypoxia stress elevated RBC number, Hb, cortisol, and glucose levels, induced the alteration of gill morphology, increased LA and GSA, stimulated respiratory frequency and PAGE, and upregulated the transcription of hif-1α and hif-2α in gill and liver. Reoxygenation treatment for 24 h alleviated the stress mentioned above effects. These findings expand current knowledge on hypoxia tolerance in black rockfish Sebastes schlegelii.


Assuntos
Brânquias/patologia , Oxigênio , Perciformes/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Glicemia/análise , Contagem de Eritrócitos , Expressão Gênica , Brânquias/metabolismo , Hemoglobinas , Hidrocortisona/sangue , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Oxigênio/análise , Perciformes/anatomia & histologia , Perciformes/sangue , Perciformes/genética , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
12.
Proc Natl Acad Sci U S A ; 117(14): 7755-7763, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32193337

RESUMO

Methionine metabolism is critical for the maintenance of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) pluripotency. However, little is known about the regulation of the methionine cycle to sustain ESC pluripotency. Here, we show that adenosylhomocysteinase (AHCY), an important enzyme in the methionine cycle, is critical for the maintenance and differentiation of mouse embryonic stem cells (mESCs). We show that mESCs exhibit high levels of methionine metabolism, whereas decreasing methionine metabolism via depletion of AHCY promotes mESCs to differentiate into the three germ layers. AHCY is posttranslationally modified with an O-linked ß-N-acetylglucosamine sugar (O-GlcNAcylation), which is rapidly removed upon differentiation. O-GlcNAcylation of threonine 136 on AHCY increases its activity and is important for the maintenance of trimethylation of histone H3 lysine 4 (H3K4me3) to sustain mESC pluripotency. Blocking glycosylation of AHCY decreases the ratio of S-adenosylmethionine versus S-adenosylhomocysteine (SAM/SAH), reduces the level of H3K4me3, and poises mESC for differentiation. In addition, blocking glycosylation of AHCY reduces somatic cell reprogramming. Thus, our findings reveal a critical role of AHCY and a mechanistic understanding of O-glycosylation in regulating ESC pluripotency and differentiation.


Assuntos
Metionina/metabolismo , Células-Tronco Pluripotentes/metabolismo , Adenosil-Homocisteinase/metabolismo , Animais , Autorrenovação Celular , Reprogramação Celular , Glicosilação , Células HEK293 , Humanos , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células NIH 3T3
13.
Sci Rep ; 10(1): 823, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964949

RESUMO

Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is a powerful and sensitive method used in gene expression analysis. Suitable reference genes, which are stable under all experimental circumstances and tissues significantly improve the accuracy of qRT-PCR data. In this study, the stability of six genes, namely, 18S ribosomal RNA (18s), beta-actin (actb), elongation factor 1-alpha (ef1α), glyceraldehyde-3-phosphate-dehydrogenase (gapdh), cathepsin D (ctsd), and beta-2-microglobulin (b2m) were evaluated as potential references for qRT-PCR analysis. The genes were examined in the hypothalamus-pituitary-ovary-liver (HPOL) axis throughout turbot ovarian development via using the geNorm, NormFinder and BestKeeper algorithms. Results showed that the most stable reference genes were ef1α, actb, and ctsd in the hypothalamus, pituitary, ovary and liver, respectively. The best-suited gene combinations for normalization were 18s, ef1α, and ctsd in the hypothalamus; actb, ctsd, and 18s in the pituitary; actb, and ctsd in the ovary; gapdh and ctsd in the liver. Moreover, the expression profile of estrogen receptor α (erα) manifested no significant difference normalization to the aforementioned best-suited gene during turbot ovarian development. However, no single gene or pair of genes is suitable as an internal control and account for the amplification differences among the four tissues during ovarian development. In summary, these results provide a basic data for the optimal reference gene selection and obtain highly accurate normalization of qRT-PCR data in HPOL axis-related gene expression analysis during turbot ovarian development.


Assuntos
Actinas/genética , Actinas/metabolismo , Linguados/crescimento & desenvolvimento , Linguados/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Expressão Gênica , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Fator 1 de Elongação de Peptídeos/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , Animais , Catepsina D/genética , Catepsina D/metabolismo , Feminino , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Fator 1 de Elongação de Peptídeos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Microglobulina beta-2/genética , Microglobulina beta-2/metabolismo
14.
Environ Sci Pollut Res Int ; 25(7): 6899-6908, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29273981

RESUMO

The development of eluent is the key to soil washing remediation, and a compound eluent was constructed using the prepared citric acid fermentation broth and saponin in this study. It displayed a good washing performance for Pb, Cu, Cr, and Cd in red soil, and the removal rates, especially Pb, gained an improvement compared with a single eluent. Based on this, the compound eluent was applied to remediation of Pb-contaminated soil in mining area; the desorption of Pb is a heterogeneous diffusion process, and Pb in large particle size soil is relatively easy to remove. An available response surface analysis model was established; its P < 0.0001 is very significant, and the P of the missing item is 0.1152. The degree of influence of three significant factors on removal of Pb is liquid-to-solid ratio > washing time > saponin concentration, and liquid-to-solid ratio and washing time show interaction. Moreover, the Pb removal rate can reach 56.20% under the optimized conditions: 0.25% saponin concentration, 20 mL/g liquid-to-solid ratio, and 320-min washing time, which is close to the predicted value of 56.20% with a difference of 1.41%. In addition, most of the active Pb was removed and environmental risks were lowered after washing.


Assuntos
Ácido Cítrico/química , Recuperação e Remediação Ambiental/métodos , Chumbo/análise , Mineração , Saponinas/química , Poluentes do Solo/análise , Fermentação , Tamanho da Partícula , Solo/química
15.
Environ Sci Pollut Res Int ; 24(10): 9506-9514, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28238181

RESUMO

The citric acid fermentation broth was prepared and it was employed to washing remediation of heavy metal-polluted soil. A well-defined washing effect was obtained, the removal percentages using citric acid fermentation broth are that 48.2% for Pb, 30.6% for Cu, 43.7% for Cr, and 58.4% for Cd and higher than that using citric acid solution. The kinetics of heavy metals desorption can be described by the double constant equation and Elovich equation and is a heterogeneous diffusion process. The speciation analysis shows that the citric acid fermentation broth can effectively reduce bioavailability and environmental risk of heavy metals. Spectroscopy characteristics analysis suggests that the washing method has only a small effect on the mineral composition and does not destroy the framework of soil system. Therefore, the citric acid fermentation broth is a promising washing agent and possesses a potential practical application value in the field of remediation of soils with a good washing performance.


Assuntos
Ácido Cítrico/química , Poluentes do Solo , Fermentação , Metais Pesados , Solo/química
16.
Sensors (Basel) ; 16(11)2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27801797

RESUMO

In this paper, the multi-walled carbon nanotubes modified screen-printed electrode (MWCNTs/SPE) was prepared and the MWCNTs/SPE was employed for the electrochemical determination of the antioxidant substance chlorogenic acids (CGAs). A pair of well-defined redox peaks of CGA was observed at the MWCNTs/SPE in 0.10 mol/L acetic acid-sodium acetate buffer (pH 6.2) and the electrode process was adsorption-controlled. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods for the determination of CGA were proposed based on the MWCNTs/SPE. Under the optimal conditions, the proposed method exhibited linear ranges from 0.17 to 15.8 µg/mL, and the linear regression equation was Ipa (µA) = 4.1993 C (×10-5 mol/L) + 1.1039 (r = 0.9976) and the detection limit for CGA could reach 0.12 µg/mL. The recovery of matrine was 94.74%-106.65% (RSD = 2.92%) in coffee beans. The proposed method is quick, sensitive, reliable, and can be used for the determination of CGA.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 492-6, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25970919

RESUMO

In the present paper, the stoichiometric ratio (R) for the interreaction of DPPH radicals with the antoxidant was employed as a evaluation index for DPPH radicals scavenging activity of antioxidants. This evaluation index was related only with the stoichiometric relationship between DPPH radicals and the antioxidant, not the relationship with the initial DPPH amount and the volume of sample, which could offer a solution for the problem of poor comparability of EC50 under different conditions. A novel photometric micro-titration method was proposed for the determination of the stoichiometric ratio (R) for the interreaction of DPPH radicals with the antoxidant. The titration equation was established based on the absorbance difference (deltaA) of DPPH radicals in the titration process and the added amount of antoxidant. The stoichiometric ratio (R) for the reaction of DPPH radicals with the addition amount of antoxidant was determined by the titration equation obtained, while, the DPPH median elimination concentration (EC50) of antoxidant can be calculated by the stoichiometric ratio (R). The above photometric micro-titration model was verified using rutin as DPPH radicals scavenger. As experiment results, the stoichiometric ratio (R) of DPPH radicals to rutin was determined to be in the range of 1.817-1.846. The calculated value of EC50 was 1.196 x 10(-3), 2.392 x 10(-3), 4.819 x 10(-3) and 7.292 x 10(-3) mg x mL(-1) for 1.12 x 10(-7), 2.24 x 10(-7), 4.48 x 10(-7) and 6.72 x 10(-7) mol of the additon amount of DPPH radicals, respectively. The proposed method has better precision and reliability with smaller amount of sample than conventional method. While, the obtained stoichiometric ratio value (R) of rutin was employed to calculate the rutin median elimination concentration for DPPH EC50) according to the conditions as reported in the literatures, and the calculated results were consistent with that reported in the literatures.


Assuntos
Sequestradores de Radicais Livres/química , Rutina/química , Fotometria , Reprodutibilidade dos Testes
18.
Artigo em Chinês | MEDLINE | ID: mdl-26016225

RESUMO

OBJECTIVE: Over the last few decades, diabetic cardiomyopathy has been identified as a significant contributor in cardiac morbidity. However, the mechanisms of diabetic cardiomyopathy have not been clarified. METHODS: In the present study, a diabetic rat model was induced by the intraperitoneal injection of streptozotocin. The myocardial CD147 expression and extent of glycosylation, as well as thematrixmetalloproteinases(MMPs) expression and activity, were observed in the diabetic and synchronous rats. RESULTS: The results showed that CD147 located on sarcolemma of cardiomyocytes. The myocardial CD147 expression and glycosylation were significantly increased in the diabetic rats as compared with the control. Expression of MMP-2 protein, MMP-2 and MMP-9 activity were also increased in left ventricular myocardium in the diabetic rats. Tamoxifen only inhibited the enhanced expression of myocardial CD147 in the diabetic rats, but not in synchronous control rats. Tamoxifen inhibited glycosylation of myocardial CD147 in both diabetic and control rats. The inhibition of tamoxifen on CD147 glycosylation was stronger than on the expression in the myocardium. The extent of myocardial CD147glycosylation was positively related toMMP-2 and MMP-9 activity. Tamoxifen induced an inhibition of myocardial MMP-2 and MMP-9 activity in the control and diabetic rats. CONCLUSION: These results indicate that myocardial CD147 expression, especially the extent of glycosylation, regulates MMP-2 and MMP-9 activity, then accelerates cardiac pathological remodeling inducing diabetic cardiomyopathy. Tamoxifen inhibits myocardial CD147 glycosylation and further depress the activity of MMPs. Therefore, tamoxifen may protect the diabetic rats against diabetic myocardium.


Assuntos
Basigina/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Miocárdio/metabolismo , Tamoxifeno/farmacologia , Animais , Diabetes Mellitus Experimental/complicações , Glicosilação , Coração/efeitos dos fármacos , Miócitos Cardíacos/citologia , Ratos , Sarcolema/metabolismo
19.
Zhong Yao Cai ; 34(1): 129-33, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21818981

RESUMO

OBJECTIVE: To optimize ultrasonic extraction technology process conditions of polyphenol from Scindapsus officinalis by the response surface method. METHODS: Based on ethanol concentration, ultrasonic time, the liquid-solid ratio of single factor experiment, the principle of design for 3 star factor 3 level response surface methodology was applied. With FC extraction method for determination of polyphenols, the response surface optimization extraction conditions were studied. RESULTS: The ethanol concentration of 61.14%, ultrasonic wave extracting time of 59.73 min and the ratio of solvent volume of 27.72:1 (Extract 3 times) were selected as the optimum conditions,the extraction yield of polyphenols was 1.352%, with the theoretical 1.361% for the relative error of -0.66%. CONCLUSION: Ultrasonic extraction is a good method for saving time, energy and material,and can be applied to the polyphenols extraction. Central composite design-response surface optimization can get better ecasting results.


Assuntos
Araceae/química , Polifenóis/isolamento & purificação , Tecnologia Farmacêutica/métodos , Ultrassom , Etanol/química , Modelos Lineares , Plantas Medicinais/química , Solventes/química , Fatores de Tempo
20.
Zhong Yao Cai ; 33(6): 984-8, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-21049625

RESUMO

OBJECTIVE: To evaluate the effectiveness of ultrasound-assisted extraction and establish the optimized extraction conditions of breviscapine from Erigeron breviscapus. METHODS: On the basis of the single factor and according to the central composite design principles (CCD), the response surface method (RSM) with 3 factors and 3 levels was adopted and the independent variables were ultrasonic wave extracting time, ethanol concentration, and the ratio of solvent volume to Erigeron breviscapus mass, breviscapine extraction yield determinated by HPLC was used as response value. RESULTS: Ultrasonic wave extracting time of 24.5 min, ethanol concentration of 74.7% and the ratio of solvent volume to Erigeron breviscapus mass of 19.8 (mL/g) were selected as optimum conditions. Regression coefficients of binomial fitting complex model was 0. 9549 and the predicted breviscapine extraction yield was 0.641%, while the actual extraction yield was 0.632% (n = 5), with relative error of -1.14%. CONCLUSION: This study confirms the efficiency of ultrasound-assisted extraction as a simple, inexpensive and effective method to improve the extraction of breviscapine from Erigeron breviscapus. The observed and predicted values are close to each other, which proves that the optimization of supersonic extraction process of breviscapine from Erigeron breviscapus by CCD-RSM is reasonable and successful.


Assuntos
Erigeron/química , Flavonoides/isolamento & purificação , Tecnologia Farmacêutica/métodos , Ultrassom , Análise de Variância , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Etanol/química , Plantas Medicinais/química , Fatores de Tempo
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