JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2019
·
IF 2.298
Xing Cui,Hai Zhu,Chao-Hong He,Ke-Jun Wu
The thermal conductivities of 1-butyl-3-methylimidazolium l-tryptophan ([BMIM][l-trp]), water, ethanol, [BMIM][l-trp] + water, [BMIM][l-trp] + ethanol, water + ethanol, and [BMIM][l-trp] + water + ethanol were investigated from 283.15 to 333.15 K covering the whole scale of concentration at atmospheric pressure with the transient hot wire method. The thermal conductivities of pure [BMIM][l-trp] decease linearly from 0.180 to 0.177 W·m–1·K–1 with increasing temperature. The uncertainty of the measurement was less than 2% at the 0.95 confidence level. The experimental data of binary and ternary mixtures were correlated by a second-order Scheffé polynomial as a function of composition and temperature. The average relative deviation of the calculated values with experimental data was 0.58%.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2019
·Vol. 7
·期 14
·2320-2329
·
IF 5.047
Ruifeng Zhu,Yuhua Zhang,Xian Fang,Xiaoqing Cui,Jing Wang,Chaochao Yue,Wenhui Fang,Hong Zhao,Zengxi Li
In this study, in situ sulfur-doped carbon nitride nanosheets (S-g-C3N4 NSs) are used as the signal readout for the sensitive and selective sensing of L-cysteine (L-Cys) in human serum samples based on the competitive coordination chemistry of Cu2+ between L-Cys and S-g-C3N4 NSs. S-g-C3N4 NSs are prepared by using trithiocyanuric acid as a precursor for the first time, which exhibits stronger electrogenerated chemiluminescence (ECL) intensity compared with pristine graphitic carbon nitride nanosheets (g-C3N4 NSs). The ECL signals of the S-g-C3N4 NSs can be quenched by Cu2+ and the subsequent presence of L-Cys can recover the ECL signals of the S-g-C3N4 NSs. These changes are ascribed to the higher coordination ability between Cu2+ and L-Cys than that between Cu2+ and the S-g-C3N4 NSs. On the basis of this, the concentration of L-Cys can be quantitatively determined. Under optimized conditions, the ECL intensity recovery shows a linear relationship with the L-Cys concentration range from 30 nM to 0.2 mM with a lower detection limit of 5 nM (S/N = 3). The proposed method is highly sensitive and selective and is thus particularly useful for fast and simple clinical diagnosis of diseases, such as Alzheimer's disease and cardiovascular disease.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2019
·
IF 4.191
Ting-ting Liu,Hai-bin Wu,Hai-bo Wu,Jing Zhang
The ethyl acetate, ethanol and water extracts of different organs (flowers, leaves, stems and roots) of wormwood ( Artemisia absinthium L.) were investigated to examine nematicidal and antifungal activities in an effort to promote future agricultural applications of the wormwood and its potential as an industrial crop. The results showed that highest concentration of total thiophene content (TTC), as well as nematicidal and antifungal activities were found in ethyl acetate extract of roots. TTC and biological activities were highly correlated, indicating that thiophenes played an important role in nematicidal and antifungal activities. Furthermore, four extraction techniques (Maceration, Soxhlet extraction, Supercritical fluid extraction and Ultrasound-assisted extraction) were compared by evaluating the yield of thiophenes. Supercritical fluid extraction (SFE) appeared to be the best method for extracting thiophenes with the highest TTC and superior activities. In addition, eight thiophenes ( 1 – 8 ) including two new compounds ( 1 and 2 ) were isolated from the SFE extract by the bioassay-guided method. All thiophenes showed potent nematicidal activities. In particular, 1 – 4 (50% lethal concentration (LC 50 ) values of 2.69, 4.17, 6.13 and 7.65 mg/L, respectively) were more effective than commercial nematicide abamectin (LC 50 , 9.47 mg/L). Also, these thiophenes showed antifungal activities against four soil-borne fungi at different degrees, especially for compounds 1 and 2 which exhibited noticeable antifungal effects (minimum inhibitory concentration (MIC) values ranging from 8–16 mg/L). Findings of this work suggest that wormwood root and its thiophenes could be used in nematicide and fungicide agent industry.
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 12
·1340
·
IF 2.935
Fang Zhang,Jing Dou,Hui Zhang
Two-dimensional metal–organic framework (MOF) nanosheets with molecular sieving properties and unique dimensional advantages are highly desired as polymer fillers for gas separation applications. Regarding polymer-supported MOF membranes, it is crucial to enhance the adhesion between the polymeric substrate and the MOF component and avoid MOF particle agglomeration. In this study, hydrophobic, embedded nanoporous nanosheets of a 2D zeolitic imidazolate framework synthesized using zinc salt and 2-methylimidazole (Hmim) aqueous solution (ZIF-L) were incorporated into a carboxymethyl cellulose (CMC) solution to form a steady mixed aqueous suspension through one-step solution blending. This prepared the composite membranes with a fine dispersion of ZIF-L nanosheets (up to loadings of 52.88 vol %) and good adhesion within the highly dense structural CMC matrix due to the strong interactions between ZIF-L and CMC, as confirmed by FTIR, Zeta potential, XPS, and SEM analysis. The potential advantages of CMC over classic polymer matrices used for gas separation mainly include: (a) Good interaction, (b) high dispersion of ZIF-L nanosheets, (c) the gas barrier nature of the CMC membrane, and (d) a facile water-based synthetic process. Based on the molecular sieving effect of ZIF-L and the gas barrier nature of the CMC matrix, gas permeation tests (H2, CO2, N2, CH4) of the mixed membrane showed a great improvement in gas selectivities compared with the CMC membrane and the reported pure ZIF membranes.Keywords:carboxymethyl cellulose;metal–organic framework nanosheets;interactions;gas permeability;gas selectivity
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2018
·
IF 3.974
Hanqin Yin,Zhenyu Qi,Mengqi Li,Golam Jalal Ahammed,Xianyao Chu,Jie Zhou
Selenium (Se) is an essential microelement for humans and a beneficial element for plants. Recently, biofortification with Se has emerged as a key strategy to increase crop Se content. Nonetheless, Se species matters a lot as inorganic Se species is mostly toxic to human health. In this study, we investigated the effects of different forms and mode of Se application on Se accumulation and speciation in rice. The results showed that root application of Se remarkably increased Se accumulation, photosynthetic rate, biomass accumulation and tolerance to cadmium stress in rice as compared to foliar application. However, the stimulatory effects of Se varied depending on the Se species used for root feeding. At vegetative stage, root application of Se-(Methyl) selenocysteine caused the highest water extractable Se content in leaves with major contribution from organic Se species such as Se-amino acid and non-amino acid organic Se. Further investigation at reproductive stage revealed that foliar application of sodium selenite (Na 2 SeO 3 ) resulted in the highest total Se content in rice seeds which was largely attributed to inorganic Se. In contrast, the root application of Na 2 SeO 3 led to the maximum accumulation of organic Se compounds which are advantageous to human health. Moreover, the root application of Se increased antioxidant capacity and selectively enhanced amino acids and essential element content in rice grain. This study deepens our understanding of the Se species in Se-enriched rice and suggests that root application of Se may ensure the safe intake of Se through rice.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2018
·
IF 2.616
Xue-Mei Kang,Xiao-Jian Zhang,Lu-Lu Hong,Feng Peng,Zhi-Qiang Liu,Yu-Guo Zheng
A novel and simple methodology for the detection of phosphinothricin produced by a biosynthesis approach in 96-well microtiter plates was developed based on the fluorometric determination of an isoindole derivative. The assay method to determine the generation of L-phosphinothricin was conducted with the help of a derivatization reaction. The linear detection range of the method was demonstrated to be from 0.74 to 100 μg ml −1 for the catalysis by resting cells and from 1.6 to 100 μg ml -1 for the catalysis by secretory enzymes. Meanwhile, the value of the relative standard deviation was less than 2.2% and the recovery was 99–101% of true value. Based on the method constructed in this study, one bacterial strain, Kluyvera cryocrescens ZJB-17005, with high stereoselectivity (>99%) and excellent yield (45%) was isolated from 13,284 strains in the production of L-phosphinothricin by a biosynthesis approach.
✓ 已验证
产品关联
DOI
高影响因子
AMB Express
·
2019
·Vol. 9
·期 1
·1-11
·
IF 2.226
Guo Zongren,Long Liangkun,Ding Shaojun
d -Mannose and l -ribose are two important monosaccharides, which have attracted public attention recently because of their great application potentials in food, cosmetic and pharmaceutical industries. Sugar isomerases catalyze the sugar isomerization and therefore can be used as the biocatalysts for production of the high-value sugars from inexpensive sugars. l -arabinose isomerase catalyzes the conversion of l -arabinose to l -ribulose, while d -lyxose isomerase catalyzes l -ribulose and d -fructose to l -ribose and d -mannose, respectively. In this paper, a putative d -LI from Bacillus velezensis (BvLI) was identified, characterized and used to produce d -mannose and l -ribose from d -fructose and l -arabinose, respectively. The recombinant BvLI exhibited a maximum activity at 55 °C and pH 6.5, in the presence of 0.1 mM Co 2+ . Approximately 110.75 g/L d -mannose was obtained from 500 g/L d -fructose in 6 h by the recombinant BvLI, and approximately 105 g/L l -ribose was obtained from 500 g/L l -arabinose in 8 h by the successive biocatalysis of l -arabinose isomerase from Bacillus licheniformis (BlAI) and BvLI.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2019
·
IF 3.571
Dongwen Hu,Tao Bao,Yang Lu,Hongming Su,Huihui Ke,Wei Chen
This study was aimed to investigate the protective effects of three different mulberry fruit polysaccharide fractions (MFP-I, MFP-II, and MFP-III) against palmitic acid (PA)-induced hepatocyte lipotoxicity and characterize the functional polysaccharide fraction using gel permeation chromatography, high-performance liquid chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance analyses. MFP-I, MFP-II, and MFP-III were isolated from mulberry fruit by stepwise precipitation with 30, 60, and 90% ethanol, respectively. MFP-II at 0.1 and 0.2 mg/mL dramatically attenuated PA-induced hepatic lipotoxicity, while MFP-I and MFP-III showed weak protection. It was demonstrated that MFP-II not only increased nuclear factor erythroid-2-related factor 2 (Nrf2) phosphorylation and its nuclear translocation, thereby activating the Nrf2/ARE signaling pathway, but also enhanced heme oxygenase 1, NAD(P)H:quinone oxidoreductase 1, and γ-glutamate cysteine ligase gene expressions and promoted catalase and glutathione peroxidase activities, which protected hepatocytes against PA-induced oxidative stress and lipotoxicity. Further investigation indicated that the molecular weight of MFP-II was 115.0 kDa, and MFP-II mainly consisted of galactose (30.5%), arabinose (26.2%), and rhamnose (23.1%). Overall, our research might provide in-depth insight into mulberry fruit polysaccharide in ameliorating lipid metabolic disorders.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD QUALITY
·
2018
·
IF 0.841
Wenxue Chen,Lan Zou,Weijun Chen,Yueying Hu,Haiming Chen
The chemical composition and antimicrobial mechanism of action of black pepper chloroform extract (BPCE) were investigated, as well as the potential antibacterial activities of BPCE against Escherichia coli and Staphylococcus aureus. The results showed that 1H-Cycloprop[e]azulen-7-ol, decahydro-1,1,7-trimethyl-4-methylene-, [1ar-(1aα,4aα,7β,7a,β,7bα.)]- (8.39%) and 2-methylene-4,8,8-trimethyl-4-vinyl-bicyclo[5.2.0]nonane (6.92%) were identified as the two primary components of BPCE. The release of intracellular transaminases from bacteria after being incubated with BPCE revealed that the bacterial cell walls and membranes were degraded and that protein synthesis was inhibited to some extent. The inhibition of bacterial Na+/K+-ATPase activity upon the addition of BPCE also indicated an enhanced permeability of bacterial cell membranes. Moreover, an analysis of hexokinase and pyruvate kinase activities showed that BPCE affected the metabolic rate of glycolysis and disrupted the normal metabolism of bacteria. This phenomenon was supported by an observed accumulation of lactic acid (LA) in the treated bacterial cells. Overall, our results indicated that BPCE damaged bacterial cell walls and membranes, which was followed by a disruption of bacterial cell respiration.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2018
·Vol. 54
·期 2
·490-498
·
IF 2.383
Zhou-Tao Fang,Chu-Jun Song,Hai-Rong Xu,Jian-Hui Ye
Summary Flavonol glycosides with low thresholds are important flavour substances in tea leaves. This study monitored the dynamic changes in flavonol glycosides during the production of different teas. The fresh leaves of cv. Fudingdabaicha with 15.77 mg g −1 of total flavonol glycosides (TFG) were respectively processed into green, yellow, white, oolong and black teas. A reduction of TFG was observed for different teas, amongst which black tea contained the lowest level of TFG (9.83 mg g −1 ), followed by oolong tea (11.96 mg g −1 ), while green, yellow and white teas contained similar levels of TFG (~13.70 mg g −1 ). Fixation was crucial to maintain the stability of flavonol glycosides due to its inactivation effect on enzymes at high temperature. Principal component analysis results indicated that flavonol glycosides were vulnerable to fermentation, and the stabilities of flavonol glycosides were related with aglycone and glycoside moiety.
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Jingling Wu,Peiyao Ran,Shu Zhu,Fangjing Mo,Cun Wang,Yingzi Fu
We present a highly sensitive platinum nanoparticles (PtNPs), rhombus-shaped rubrene microsheets (RubRMs) and dissolved oxygen (O 2 ) system for the monitoring of l -cysteine by the quenched electrochemiluminescence (ECL) signals. Firstly, RubRMs has been prepared through reprecipitation method, then the metal organic composites of PtNPs-RubRMs was synthesized by a simple in situ reduction of PtNPs on RubRMs surface. The composites combined the high ECL characteristic of RubRMs, the wonderful catalytic efficiency and good electron transfer ability of PtNPs. With the synergistic effect between RubRMs and PtNPs, the proposed ECL sensors exhibited excellent responses for l -cysteine. Under the optimum conditions, the linear range was from 1.0 × 10 −9 mol L -1 to 5.0 × 10 -4 mol L -1 with a detection limit of 3.3 × 10 -10 mol L -1 (S/N = 3). And the results shows high sensitivity, excellent stability, and low background signal. It is simple to prepare and operate for the practical application.
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2018
·Vol. 8
·期 8
·326
·
IF 3.465
Peng Sun,Jun Zhang,Wenxiu Liu,Qi Wang,Wenbin Cao
In this paper, the Langmuir-Hinshelwood (L-H) model has been used to investigate the kinetics of photodegradation of gaseous benzene by nitrogen-doped TiO2(N-TiO2) at 25 °C under visible light irradiation. Experimental results show that the photoreaction coefficientkpmincreased from 3.992 × 10−6mol·kg−1·s−1to 11.55 × 10−6mol·kg−1·s−1along with increasing illumination intensity. However, the adsorption equilibrium constantKLdecreased from 1139 to 597 m3·mol−1when the illumination intensity increased from 36.7 × 104lx to 75.1 × 104lx, whereas it was 2761 m3·mol−1in the absence of light. This is contrary to the fact thatKLshould be a constant if the temperature was fixed. This phenomenon can be attributed to the breaking of the adsorption-desorption equilibrium by photocatalytically decomposition. To compensate for the disequilibrium of the adsorption-desorption process, photoreaction coefficientkpmwas introduced to the expression ofKLand the compensation form was denoted asKm.KLis an indicator of the adsorption capacity of TiO2whileKmis only an indicator of the coverage ratio of TiO2surface. The modified L-H model has been experimentally verified so it is expected to be used to predict the kinetics of the photocatalytic degradation of gaseous benzene.Keywords:modified L-H model;N-TiO2;photocatalytic degradation;benzene
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）