SEPARATION AND PURIFICATION TECHNOLOGY
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2019
·
IF 5.107
Chun Huang,Yulan Wang,Miao Gong,Wei Wang,Yang Mu,Zhen-Hu Hu
The discharging of Rhodamine B (RhB) from wastewater has caused huge environment pollution. Peroxymonosulfate (PMS) oxidation is an effective way to remove it from wastewater. However, finding an environmentally friendly metal to activate PMS is a key step for the oxidation process. In this study, nanorod α-MnO 2 loaded palygorskite (α-MnO 2 /Pal) was fabricated by a simple hydrothermal method. The analysis of field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) confirmed the loading of α-MnO 2 on the surface of Pal and characterized the surface of the composite. The surface area of α-MnO 2 /Pal composite was 159.13 m 2 /g, which was much higher than that of Pal and α-MnO 2 . The Pal, α-MnO 2 , Mn 2+ , and α-MnO 2 /Pal were used to activate PMS for RhB degradation. Nearly 100% RhB degradation was obtained in α-MnO 2 /Pal + PMS system in 180 min and in α-MnO 2 + PMS system in 300 min, while only 50% degradation was obtained in Pal + PMS system and 71.4% degradation in Mn 2+ + PMS system in 300 min. The degradation fitted the pseudo-first-order reaction kinetics well with rate constant of 0.02041 min −1 for α-MnO 2 /Pal + PMS system, 0.01192 min −1 for α-MnO 2 + PMS system, and 0.00435 min −1 for Mn 2+ + PMS system, respectively. The factors affecting RhB degradation were further investigated. The RhB degradation efficiency increased with the increase of α-MnO 2 /Pal dosages, PMS dosages and temperatures. The degradation was inhibited at pH > 5.5, while was favorable at pH < 5.5. The major reactive radicals responsible for RhB degradation classified by radical quenching experiment were O 2 − and 1 O 2 . The possible mechanism was further proposed based on the results. The α-MnO 2 /Pal composite showed nearly 50% mineralization ratio in the presence of PMS and an excellent reusability. The results from this study revealed that α-MnO 2 /Pal composite is an effective catalyst to activate PMS for RhB degradation.
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INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
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2019
·Vol. 54
·期 6
·2084-2093
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IF 2.281
Mohamed Abdin,Yahya Saud Hamed,Hafiz Muhammad Saleem Akhtar,Dan Chen,Shanza Mukhtar,Peng Wan,Asad Riaz,Xiaoxiong Zeng
Summary The objectives of this study were to determine the optimal extraction conditions of polyphenols from Syzygium cumini seeds by response surface methodology and investigate their antioxidant activity and inhibition on α-amylase and pancreatic lipase. As results, the optimal extraction conditions in the ultrasonic extraction process which maximised total polyphenols content, minimised the IC 50 values of α-amylase and pancreatic lipase were determined as follows: extraction time 60 min, ethanol concentration 63% and solvent/solid ratio 44 mL g −1 . The main phenolic compounds in partially purified fraction of Syzygium cumini seeds were catechin, epicatechin, kaempferol, gallic, 5-caffeoylquinic, caffeic and ferulic acids. In addition, the partially purified fraction inhibited 87.66 ± 5.55 and 86.61 ± 3.15% of α-amylase and pancreatic lipase, respectively. The results suggested that Syzygium cumini seeds could be explored as a natural antioxidant and could be used as a source of highly antidiabetic and anti-obesity bioactive compounds.
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Journal of Zhejiang University-SCIENCE B
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2019
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IF 1.879
Su-fang Gu,Li-ying Wang,Ying-jie Tian,Zhu-xian Zhou,Jian-bin Tang,Xiang-rui Liu,Hai-ping Jiang,You-qing Shen
Hesperetin, an abundant bioactive component of citrus fruits, is poorly water-soluble, resulting in low oral bioavailability. We developed new formulations to improve the water solubility, antioxidant activity, and oral absorption of hesperetin. Two nano-based formulations were developed, namely hesperetin-TPGS ( D -α-tocopheryl polyethylene glycol 1000 succinate) micelles and hesperetin-phosphatidylcholine (PC) complexes. These two formulations were prepared by a simple technique called solvent dispersion, using US Food and Drug Administration (FDA)-approved excipients for drugs. Differential scanning calorimetry (DSC) and dynamic light scattering (DLS) were used to characterize the formulations’ physical properties. Cytotoxicity analysis, cellular antioxidant activity assay, and a pharmacokinetic study were performed to evaluate the biological properties of these two formulations. The final weight ratios of both hesperetin to TPGS and hesperetin to PC were 1:12 based on their water solubility, which increased to 21.5-and 20.7-fold, respectively. The hesperetin-TPGS micelles had a small particle size of 26.19 nm, whereas the hesperetin-PC complexes exhibited a larger particle size of 219.15 nm. In addition, the cellular antioxidant activity assay indicated that both hesperetin-TPGS micelles and hesperetin-PC complexes increased the antioxidant activity of hesperetin to 4.2-and 3.9-fold, respectively. Importantly, the in vivo oral absorption study on rats indicated that the micelles and complexes significantly increased the peak plasma concentration ( C max ) from 2.64 μg/mL to 20.67 and 33.09 μg/mL and also increased the area under the concentration–time curve of hesperetin after oral administration to 16.2-and 18.0-fold, respectively. The micelles and complexes increased the solubility and remarkably improved the in vitro antioxidant activity and in vivo oral absorption of hesperetin, indicating these formulations’ potential applications in drugs and healthcare products.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
·
IF 8.355
Lei Ding,Li Liu,YiFan Chen,Yunzhe Du,ShengJie Guan,Yongping Bai,Yudong Huang
Ultraviolet-shielding poly(ethylene α-truxillate-co-ethylene terephthalate) (PETT) was synthesized via the addition of α-truxillic acid (TA) as a third monomer in the copolymerization modification of poly (ethylene terephthalate) (PET). The effects of TA, with its semi-flexible/semi-rigid special structure, on the chemical structure, thermal properties, crystallization behavior, ultraviolet blocking properties, and mechanical properties of PETT were then investigated. Thermal analysis revealed that a small amount of TA significantly reduced the crystallinity and melting temperature of PETT but did not affect its thermal stability. Notably, the material exhibited excellent thermal properties in processing applications. With the addition of only 10 wt%, PETT could block ~100% of the ultraviolet spectrum (<400 nm), making up for the defect that pristine PET cannot shield the UV-A spectrum (320–400 nm). The yield stress also increased significantly from 29.8 MPa for the neat PET to 40.2 MPa for PETT (10 wt% TA). In addition, the TA is plant-derived and synthesized by environmentally friendly photodimerization reaction. A small amount of TA provides PET with excellent ultraviolet shielding performance and mechanical properties, broadening its application prospects in the field of anti-ultraviolet packaging materials.
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APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
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2019
·Vol. 103
·期 15
·6119-6128
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IF 3.67
Zhang Wenhe,Zhu Tianhui,Li Hengyu,Qin Fengyu,Zhang Feiting,Zhang Rui,Jia Xian,Qin Bin,You Song
Biocatalytic reduction catalyzed by aldo-keto reductases (AKRs) is a valuable approach for asymmetric synthesis of chiral alcohols. In this study, four novel aldo-keto reductases with significant activity and stereoselectivity toward a variety of α-keto esters and halogen-substituted acetophenones were identified by genome mining. Through analysis of the crystal structure and multiple-sequence alignment of the starting AKR YvgN from Bacillus subtilis , residues F25 and W113 were proposed as the key positions that might control the stereoselectivity of YvgN. F25S and F25S/W113F variants of YvgN were able to improve its activity and stereoselectivity toward some α-keto ester compounds and halogen-substituted acetophenone derivatives. In addition, similar enhancement of catalytic activity and stereoselectivity was also found in the other three AKRs with corresponding mutations of starting YvgN.
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ChemSusChem
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2018
·Vol. 11
·期 13
·2156-2164
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IF 7.411
Feng Li,Jing Li,Jie Zhang,Lili Gao,Xuefeng Long,Yiping Hu,Shuwen Li,Jun Jin,Jiantai Ma
Graphical Dope to promote : A high-performance photoanode consisting of NiO nanoparticles anchored on a gradient P-doped α-Fe 2 O 3 nanorod array (NiO/P-α-Fe 2 O 3 ) is successfully fabricated. The electrochemical results show that the photoanode presents a high photocurrent density and long-term stability for improved water oxidation. The photoelectrochemical (PEC) water-splitting efficiency of a hematite-based photoanode is still far from the theoretical value due to its poor surface reaction kinetics and high density of surface trapping states. To solve these drawbacks, a photoanode consisting of NiO nanoparticles anchored on a gradient phosphorus-doped α-Fe 2 O 3 nanorod (NR) array (NiO/P-α-Fe 2 O 3 ) was fabricated to achieve optimal light absorption and charge separation, as well as rapid surface reaction kinetics. Specifically, a photoanode with the NR array structure allowed a high mass-transport rate to be achieved, while phosphorus doping effectively decreased the number of surface trapping sites and improved the electrical conductivity of α-Fe 2 O 3 . Furthermore, the p–n junction that forms between NiO and P-α-Fe 2 O 3 can further improve the PEC performance due to efficient hole extraction and the water oxidization catalytic activity of NiO. Consequently, the NiO/P-α-Fe 2 O 3 NR photoanode produced a high photocurrent density of 2.08 mA cm −2 at 1.23 V versus a reversible hydrogen electrode and a 110 mV cathodic shift of the onset potential. This rational design of structure offers a new perspective in exploring high-performance PEC photoanodes.
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BIOMEDICAL CHROMATOGRAPHY
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2018
·Vol. 32
·期 9
·e4281
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IF 1.688
Peng-Cheng Guo,Hua-Dan Shen,Jiang-Ji Fang,Tian-Ming Ding,Xiao-Ping Ding,Jun-Feng Liu
An on-line high-performance liquid chromatography–biochemical detection (HPLC-BCD) method, in which compounds separated by HPLC were on-line reacted with enzyme and substrate solutions delivered by flow injection and the enzyme inhibition signal was collected by UV detection, was developed to rapidly screen α -glucosidase inhibitors from green tea extracts in this study. The chromatographic fingerprints and enzyme inhibition profiles of the different brands of green tea could be simultaneously detected by the on-line HPLC-BCD method. Enzyme inhibition profiles were detected by the UV detector at 415 nm based on the reaction of α -glucosidase and p -nitrophenyl α - d -glucopyranoside (PNPG). PNPG (1.25 m m ), α -glucosidase (0.4 U/mL) and the flow rate 0.07 mL/min were applied as optimized parameters to detect α -glucosidase inhibitors in green tea. Four components in green tea showed α -glucosidase inhibition action and three of them were identified as HHDP-galloyl glucose, (−)-epigallocatechin-3-gallate and (−)-epicatechin-3-gallate by HPLC–fourier-transform mass spectrometry (HPLC-FTMS). Two brands of green tea derived from Mengding and Enshi mountainous areas might be superior to the other samples in the prevention and treatment of diabetes owing to their stronger activities of enzyme inhibitors. The proposed on-line HPLC-BCD method could be used to rapidly identify the potential enzyme inhibitors in complex matrixes.
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ACS Applied Materials & Interfaces
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2018
·
IF 8.097
Zhong-Shuai Zhu,Jin Qu,Shu-Meng Hao,Shuang Han,Kun-Le Jia,Zhong-Zhen Yu
High activity and long-term stability are particularly important for peroxymonosulfate (PMS)-based degradation processes in wastewater treatment, especially under a flowing state. However, if the highly active nanomaterials are in a powder form, they could disperse well in water but would not be convenient for application under varied flow rates. A metal oxide/bacterial cellulose hybrid membrane fixed in a flowing bed is expected to solve these problems. Herein, α-Fe2O3 nanodisk/bacterial cellulose hybrid membranes as high-performance sulfate-radical-based visible light photocatalysts are synthesized for the first time. The bacterial cellulose with excellent mechanical stability and film-forming feature not only benefits the formation of a stable membrane to avoid the separation and recycling problems but also helps disperse and accommodate α-Fe2O3 nanodisks and thus enhances the visible light absorption performances, leading to an excellent PMS-based visible light degradation efficiency under both stirring and flowing states. Particularly, the optimized hybrid membrane photocatalyzes both cationic and anionic organic dyes under a flowing bed state for at least 84 h with the catalytic efficiency up to 100% and can be easily separated after the reaction, confirming its remarkable catalytic performance and long-term stability. Even under varied flow rates during the continuous process, it efficiently degrades rhodamine B and orange II from 3 to 16 mL h–1. When the flow rate goes back from high to low, the hybrid membrane quickly recovers its original performance, demonstrating the high activity and stability of the α-Fe2O3/bacterial cellulose membrane.
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Polymers
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2018
·Vol. 10
·期 10
·1082
·
IF 2.935
Dongmei Han,Yiqing Luo,Qing Ju,Xujing Xiao,Min Xiao,Naiyu Xiao,Shou Chen,Xiaohua Peng,Shuanjin Wang,Yuezhong Meng
Nanobrick wall hybrid coating with super oxygen barrier properties were fabricated on polyethylene terephthalate (PET) film using a quadlayer (QL) assembly of polyelectrolytes and nanoplateles. A quadlayer assembly consists of three repeat units of polyacrylic acid (PAA), poly (dimethyl diallyl ammonium chloride) (PDDA) and layered α-zirconium phosphate (α-ZrP). PDDA with positive charges can assemble alternatively with both α-ZrP and PAA with negative charges to form nanobrick wall architectures on the surface of PET film via the electrostatic interaction. The lamellar structure of α-ZrP platelets and the dense QL assembly coating can greatly reduce the oxygen transmission rate (OTR) of PET film. Compared to pristine PET film, the OTR of PET (QL)19is reduced from 57 to 0.87 cc/m2/day. Moreover, even with 19 QLs coating, PET (QL)19composite film is still with an optical transparency higher than 90% and a haze lower than 10%. Therefore, the transparent PET (QL)ncomposite films with super oxygen barrier properties show great potential application in food packaging and flexible electronic packaging.Keywords:nanobrick;electrostatic interaction;oxygen barrier;packaging applications
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JOURNAL OF HAZARDOUS MATERIALS
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2018
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IF 6.434
Amir. E. Kaziem,Yunhao Gao,Yuan Zhang,Xueying Qin,Yanan Xiao,Yanhui Zhang,Hong You,Jianhong Li,Shun He
α-Amylase-responsive carrier for controlled release of avermectin (AVM) was prepared based on α-cyclodextrin (α-CD) anchored hollow mesoporous silica (HMS) using α-CD as a capping molecule. The release of AVM was studied at different temperatures, pH values and in the presence or absence of α-amylase. The results revealed that the AVM-encapsulated controlled release formulation (AVM-CRF) has a drastic enzymatic dependence, an excellent encapsulation efficacy reaching 38%, and outstanding UV and thermal shielding ability. The AVM-CRF biological activity survey shows excellent toxicological properties against Plutella xylostella larvae, which confirms that α-CD caps could be uncapped enzymatically in vivo and release AVM, inducing P. xylostella larval death. AVM-CRF has a notable capability to keep 0.6 mg L −1 AVM biologically active until 14th day with 83.33% mortality of the target insect, which was 40% higher than that of treated with AVM commercial formulation. The study provides a theoretical basis for the application of pesticide reduction.
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FOOD AND CHEMICAL TOXICOLOGY
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2018
·
IF 3.977
Jian Fang,Qiuyan Chen,Baozhu He,Jiaxuan Cai,Yawen Yao,Yi Cai,Suowen Xu,Kannan R.R. Rengasamy,Shanmugaraj Gowrishankar,Shunmugiah Karutha Pandian,Tiansheng Cao
Tanshinone IIA is one of the most predominant bioactive constituents of Danshen , a traditional Chinese medicinal plant with multiple cardiovascular protective actions. Although Tanshinone IIA has been well documented for its endothelial protective efficacy, studies unveiling the mechanism and/or molecular targets for its pharmacological activity are still inadequate. In recent studies, it has been envisaged that the expression of pentraxin 3 (PTX3) was associated with atherosclerotic cardiovascular diseases (ACVD). Therefore, the current study was designed to evaluate the possible role of Tanshinone IIA in influencing the expression of PTX3 in endothelial cells and thereby prevents endothelial dysfunction . Molecular analyses through real-time PCR, western blot , and ELISA revealed that Tanshinone IIA down-regulates PTX3 gene expression as well as protein secretion in human endothelial cells in the presence or absence of TNF-α. Besides, Tanshinone IIA inhibits the adhesion of THP1 cells (a monocytic cell line) to activated-endothelial cells stimulated with TNF-α. Furthermore, mechanistic studies uncovered the role of p38 MAPK/NF-κB pathway in Tanshinone II-A mediated pharmacological effects. Thus, the present study exemplifies the manifestation of Tanshinone IIA as a plausible alternative natural remedy for ACVD by targeting PTX3.
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JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2018
·
IF 3.235
Xianjiu Liao,Jianjun Luo,Jing Wu,Taotao Fan,Yao Yao,Fenglei Gao,Yong Qian
In this work, a sensitive DNAzyme-based electrochemical sensor had been developed for Pb 2+ detection with platinum nanoparticles decorated TiO 2 /α-Fe 2 O 3 composite as signal labels. The morphological and compositional properties of the PtNPs/TiO 2 /α-Fe 2 O 3 were examined by using transmission electron microscopy , X-ray diffraction, and X-ray photoelectron spectroscopy. The result showed that the shape of α-Fe 2 O 3 nanocrystals were the cubic, the average length ranged from 150 to 300 nm, and the PtNPs with about 3–4 nm in diameter were well dispersed on the surface of TiO 2 /α-Fe 2 O 3 . TiO 2 /α-Fe 2 O 3 were used as a “carrier” to load the PtNPs tracers as well as for Apt3 immobilization. In turn, the DNAzyme structure of Apt1 and Apt2 was immobilized on the gold electrode surface as the capture probes. Subsequently, DNAzyme modified electrodes reacted with target Pb 2+ and the Apt3/PtNPs/TiO 2 /α-Fe 2 O 3 composite were deposited on the electrode surface. The performance of the DNAzyme-based electrochemical sensor was tested by recording the electrocatalytic reduction current toward H 2 O 2 . Enhanced sensitivity was achieved by TiO 2 /α-Fe 2 O 3 nanocomposites as a nanocarrier in order to PtNPs at a high ratio. The DNAzyme-based electrochemical sensor described here exhibited excellent sensitivity and specificity for target ion. This work represented a promising potential for on-site testing Pb 2+ in real drinking water and serum sample analysis.
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危险品化学品经营许可证（带存储）