JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY
·
2020
·Vol. 96
·期 3
·233-243
·
IF 1.56
Liu Kai,Liu Huijun,Li Zhendong,Li Wei,Li Liuxing
The co-evaporation method was used to synthesize the EN-β-CD@Piperine inclusion complex with a molar ratio of 1:1. The properties and structures of the inclusion complex were characterized by various methods to investigate the inclusion mode and interactions between host and guest. The results of molecular modeling were theoretically analyzed to determine the inclusion mechanism of inclusion complexes. Finally, the vitro dissolution release studies showed that the water solubility of piperine was significantly enhanced when EN-β-CD was combined with piperine. Therefore, the EN-β-CD@Piperine inclusion complex provides a promising development for the clinical application of piperine in the future.
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高影响因子
Natural Product Communications
·
2020
·
IF 0.468
Xue Zhen Feng,Zhuanquan Xiao,Li Zhang,Shengliang Liao,Shangxing Chen,Hai Luo,Lu He,Guorong Fan,Zongde Wang
β-Pinene can be used as a cheap source to synthesize a large number of high value-added derivatives. In this study, a series of β-pinene derivatives was prepared, and the antifungal activities of the compounds were assessed against phytopathogenic fungi. Eight N-alkyl hydronopyl diethyl ammonium halide salts were synthesized by the reaction of hydronopyl diethyl ammonium halide with 8 halogenated alkanes. The structures of the synthesized products were characterized by Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy and mass spectrometry. The antifungal activities of these derivatives were tested against 11 plant pathogens, and the preliminary structure-activity relationship is discussed. Some derivatives exhibited moderate to significant antifungal activity due to the fusion of the hydronopyl, a long-chain alkyl, bromine, and iodine anionic groups. In contrast to the structure-activity relationship of compounds 2a, 2b, and 2c, iodine ions in 2f, 2g, and 2f had a significant effect on enhancing the antifungal activity against Colletotrichum gloeosporioides, Sclerotinia sclerotiorum, Phytophthora capsici, Phomopsis, Sphaeropsis sapinea, Glomerella cingulata, and Fusicoccum aesculi. A higher molecular weight could increase the antifungal activity against Fusarium proliferatum, Alternaria kikuchiana, Sclerotinia sclerotiorum, P. capsici, Phomopsis, and S. sapinea. Compounds 2d and 2e exhibited broad-spectrum antifungal activity against the tested strains. These derivatives are expected to be used as precursor molecules for novel pesticide development in further research.
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INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2020
·Vol. 21
·期 5
·1709
·
IF 4.556
Juan Guo,Huan Guo,Jin Liu,Fangrui Zhong,Yuzhou Wu
Manganese oxidizing bacteria can produce biogenic manganese oxides (BMO) on their cell surface and have been applied in the fields of agriculture, bioremediation, and drinking water treatment to remove toxic contaminants based on their remarkable chemical reactivity. Herein, we report for the first time the synthetic application of the manganese oxidizing bacteria,Pseudomonas putidaMnB1 as a whole-cell biocatalyst for the effective oxidation of β-keto ester with excellent yield. Differing from known chemical protocols toward this transformation that generally necessitate the use of organic solvents, stoichiometric oxygenating agents and complex chemical catalysts, our strategy can accomplish it simply under aqueous and mild conditions with higher efficiency than that provided by chemical manganese oxides. Moreover, the live MnB1 bacteria are capable of continuous catalysis for this C-O bond forming reaction for several cycles and remain proliferating, highlighting the favorable merits of this novel protocol for sustainable chemistry and green synthesis.Keywords:Pseudomonas putidaMnB1;biogenic manganese oxides;abiotic manganese oxides;α-Hydroxy-β-keto esters;whole-cell biocatalysis
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高影响因子
DALTON TRANSACTIONS
·
2020
·Vol. 49
·期 27
·9268-9273
·
IF 4.174
Lu He,Chuan Tan,Chuanchao Sheng,Yuanzhao Chen,Fengjiao Yu,Yuhui Chen
FeOOH is one of the earth abundant and high-capacity anode materials for lithium-ion batteries (LIBs), but faces problems of inevitable structure collapse and thus poor capacity retention. Herein, we report a composite of β-FeOOH/Ti3C2Tx MXene sandwich by an intercalation of β-FeOOH nanorods within single-layer Ti3C2Tx MXene flakes. After 100 cycles, the β-FeOOH/Ti3C2Tx composite retains a capacity of 937.5 mA h g−1 at 200 mA g−1, and 671.4 mA h g−1 at 1 A g−1. The composite as an anode in LIB delivers improved cyclability and better high-rate performance compared to pristine β-FeOOH, which result from the excellent conductivity of single-layer MXene, facilitating mass transport by the sandwich structure. This work provides a strategy for the design of electrodes, particularly in Na-ion and K-ion batteries, which involve active materials that experience volume change and structural damage during cycling.
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CHEMICAL ENGINEERING SCIENCE
·
2020
·
IF 3.871
Li-Chao Wang,Lian Xu,Xin-Qi Xu,Bing-Mei Su,Juan Lin
L-threonine aldolase (LTA) is a PLP-dependent enzyme that can reversibly catalyze aldol reaction of glycine and acetaldehyde to produce β -hydroxy- α -amino acids. In the present work, a putative lta gene from Actinocorallia herbida (AhLTA) was mined and over-expressed in Escherichia coli BL21 (DE3). The substrate spectrum assay indicated that AhLTA only used glycine as donor substrate and tolerated a wild range of aromatic aldehydes as acceptor substrates. It was found that the type and position of substituents in the aromatic aldehydes exerted a significant impact on the activity and stereoselectivity at β -carbon of AhLTA. Among those substrates, AhLTA could catalyze glycine and 4-methylsulphonyl benzaldehyde ( 14a ) to produce L- threo -4-methylsulfonylphenylserine ((2 S ,3 R )- 14b ) with high conversion (94.4%) and moderate stereoselectivity (19% de ). By conditional optimization, the de value of (2 S , 3 R )- 14b was improved to 61% and the conversion was 75%. Taken together, our study suggested that AhLTA might be a promising catalyst for producing chiral β -hydroxy- α -amino acids.
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Journal of Materials Chemistry B
·
2020
·Vol. 8
·期 26
·5776-5782
·
IF 5.344
Yueling Xu,Lehui Xiao
The deposition of amyloid plaques resulting from the aggregation of amyloid-β (Aβ) peptides is closely related to Alzheimer's disease (AD). With the development of various therapeutic methods, the oxidative modification of Aβ has emerged as a fascinating noninvasive photo-therapeutic intervention for treating AD by altering the Aβ aggregation tendency. Herein, we report the photo-triggered inhibition of Aβ aggregation and cytotoxicity by utilizing polymer nanodots (Pdots) modified with rose bengal (RB), methylene blue (MB), and riboflavin (RF). Experimental results demonstrate that these functionalized Pdots manifest a superior suppression effect on Aβ aggregation under irradiation. This can be attributed to the formation of reactive oxygen species (ROS) (i.e., singlet oxygen (1O2)), resulting in the oxygenation of Aβ and the change of Aβ aggregation tendency. Especially, RB-Pdots manifest better biocompatibility and higher 1O2 productivity. In a word, this hybridized nanostructure will provide a promising platform for the noninvasive photo-therapeutic treatment of AD in the future.
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BMC Complementary Medicine and Therapies
·
2020
·Vol. 20
·期 1
·1-10
·
IF 0
Liu Shou Gang,Luo Guang Pu,Qu Yong Bin,Chen Yong Feng
Background Psoriasis is a common inflammatory skin disease. Abnormal proliferation of keratinocytes is one of the psoriatic histopathological features. Indirubin has an essential effect on the proliferation and activation of keratinocytes; however, in psoriasis, the specific mechanism of action of indirubin on keratinocytes is unclear. In the present study, we revealed the effects of indirubin on DNA methyltransferase 1 (DNMT1), wnt inhibitory factor 1 (wif-1), and wnt/β-catenin signal pathway, in the meantime, we explored the effects of indirubin on proliferation, cell cycle and the apoptosis of HaCaT cells.Methods The expression of DNMT1, wif-1, Frizzled2, Frizzled5, and β-catenin in HaCaT cells treated with different concentrations of indirubin were detected by Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). The expression levels of DNMT1 and wif-1 were observed after treated with different concentrations of indirubin by enzyme-linked immunosorbent assay (ELISA). The wif-1 promoter methylation status was detected by DNA methylation-specific PCR (MSP). The transcriptional activities of wif-1 and β-catenin were discovered by a luciferase reporter gene system. Cell viability was determined by Cell Counting Kit-8 (CCK8) method. The cell cycle was detected by flow cytometry. The apoptotic cells were surveyed by the apoptosis kit. The expression of Inolucrin, Loricrin, Filaggrin, Keratin 17, and transcriptional activation of transglutaminase 1(TGase1) were detected by Western blotting.Results Indirubin inhibited the expression of DNMT1 and the methylation of the wif-1 promoter. In the wnt signal pathway, indirubin restored the protein expression of wif-1 and inhibited expression of Frizzled2, Frizzled5, and β-catenin. Besides, indirubin inhibited the proliferation of HaCaT cells, induced apoptosis, and arrest cell cycle. We also reported that indirubin could down-regulate the expression of Involucrin, TGase 1, and keratin 17, but the expression of Filaggrin and Loricrin had no significant effect.Conclusion Our research showed that indirubin promoted the demethylation of wif-1 and suppressed the wnt/β-catenin signal pathway, thereby exerted an anti-proliferative effect. This study reveals the anti-proliferation mechanism of indirubin, which may provide an effective option for the treatment of proliferative diseases.
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ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Xianshu Qiao,Hongjun Kang,Yang Li,Kai Cui,Xin Jia,Henghao Liu,Wei Qin,Max Pupucevski,Gang Wu
We report a highly efficient and stable electrode composed of a porous Fe-doped β-nickel hydroxide nanopyramid array supported on nickel foam (U–Fe-β-Ni(OH)2/NF) for overall water splitting. The unique structure is assembled via a self-templated strategy by utilizing the FeNi oxalate (FeNi–C2O4/NF) nanopyramid as the templates, followed by an anion-exchange reaction at room temperature. Due to the intrinsic activity of Fe-doped β-Ni(OH)2 along with unique porous array structures consisting of two-dimensional (2D) active materials on three-dimensional (3D) conductive substrates, the developed electrode exhibited outstanding electrocatalytic activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in an alkaline medium. The introduced amount of Fe plays a significant role in promoting OER and HER activity compared to the β-Ni(OH)2 electrode. The optimal electrode (U–Fe-β-Ni(OH)2/NF-2) generated a current density of 10 mA cm–2 at low overpotentials of 218 mV for the OER and 121 mV for the HER. The electrode also demonstrated considerably stable performance during the continuous water splitting process. Furthermore, we elucidated the promotion mechanisms of the active Fe-doped β-Ni(OH)2 compound for the OER and HER based on extensive characterization and electrochemical measurements. Hence, this work provides a facile approach to developing low-cost, efficient, and stable hydroxide-based electrodes for bifunctional OER and HER in water splitting.
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高影响因子
MOLECULES
·
2020
·Vol. 25
·期 9
·2109
·
IF 3.267
Changzhou Chen,Peng Liu,Haihong Xia,Minghao Zhou,Jiaping Zhao,Brajendra K. Sharma,Jianchun Jiang
It is of great importance to explore the selective hydrogenolysis of β-O-4 linkages, which account for 45–60% of all linkages in native lignin, to produce valued-added chemicals and fuels from biomass employing UV light as catalyst. TiO2exhibited satisfactory catalytic performances in various photochemical reactions, due to its versatile advantages involving high catalytic activity, low cost and non-toxicity. In this work, 20 wt.% Ni/TiO2and oxidant PCC (Pyridinium chlorochromate) were employed to promote the cleavage of β-O-4 alcohol to obtain high value chemicals under UV irradiation at room temperature. The Ni/TiO2photocatalyst can be magnetically recovered and efficiently reused in the following four consecutive recycling tests in the cleavage of β-O-4 ether bond in lignin. Mechanism studies suggested that the oxidation of β-O-4 alcohol to β-O-4 ketone by oxidant PCC first occurred during the reaction, and was followed by the photocatalysis of the obtained β-O-4 ketone to corresponding acetophenone and phenol derivates. Furthermore, the system was tested on a variety of lignin model substrates containing β-O-4 linkage for the generation of fragmentation products in good to excellent results.Keywords:lignin;β-O-4;photocatalyst;Ni/TiO2;oxidant PCC
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CHEMOSPHERE
·
2019
·
IF 5.108
Boyin Yan,Zhiquan Liu,Rui Huang,Yongpeng Xu,Dongmei Liu,Wei Wang,Zhiwei Zhao,Fuyi Cui,Wenxin Shi
Cyanobacteria produce a series of secondary metabolites , one of which is beta- N -methylamino- l -alanine (BMAA). BMAA is considered to be the cause of human neurodegeneration. Compared with other cyanotoxins, the role of BMAA in cyanobacteria remains unclear. To investigate this question, six strains of cyanobacteria were cultured and tested in this experiment with an optimized and validated BMAA determination method. The results show that four strains can produce BMAA. The effects of nutrient levels on the production of BMAA by Anabaena sp. FACHB-418 were studied by changing the initial concentrations of nitrate (NaNO 3 ) and phosphate (K 2 HPO 4 ) in mediums. Bound BMAA was detected in all samples and the concentrations were within 50–100 ng/g. Free BMAA was presence when the concentration of nitrogen was lower than 1.7 mg/L (121.43 μM). Free BMAA was released from the dead and ruptured cells during the cell decline period, so dissolved BMAA cannot be detectable in the adaptation and logarithmic periods, but could be abundant in the decline periods. Statistical analyses show that free BMAA concentrations were negatively correlated with nitrogen strongly (p = 2.334 × 10 −10 and r = −0.842), but positively correlated with phosphorus weakly (p = 0.016 and r = 0.405). Moreover, the results of culture experiments indicated that exogenous BMAA could inhibit the growth of cyanobacteria that cannot produce BMAA, and the effect was enhanced as the concentration of exogenous BMAA increased. This phenomenon implies that the production of BMAA may be the stress response by some cyanobacteria to low nitrogen conditions to kill other cyanobacteria, i.e., their competitors.
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MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-9
·
IF 5.479
Shi Jianrong,Li Geyuan,Cui Yanru,Zhang Yan,Liu Donghao,Shi Yi,He Hua
β-Cyclodextrin-functionalized carbon nitride nanosheets were modified with a molecularly imprinted polymer to obtain a fluorescent probe of type MIP@β-CD/CNNS which is shown to enable fluorometric determination of sterigmatocystin (STG). The material was characterized by transmission electron microscopy, infrared spectra, powder X-ray diffraction, X-ray photoelectron spectroscopy, and by absorption and emission spectra. The modified CNNSs have a good fluorescence quantum yield (13%), high sorption capacity for STG (86 mg·g −1 ), fast adsorption rate (25 min), and superior adsorption selectivity (with an imprint factor 2.56). When used as an optical probe for STG, the CNNSs act as the chromophore, while β-CD and MIP act as the recognition groups. The blue fluorescence of MIP@β-CD/CNNS (with excitation/emission maxima at 368/432 nm) is quenched by STG. Fluorescence drops linearly in the 0.15 to 3.1 μM STG concentration range. The lower detection limit is 74 nM. The method was successfully applied to the determination of STG in spiked wheat extract. Conceivably, this detection scheme based on a combination of β-CD inclusion and molecular imprinting may be extended to the detection of various other organic compounds.
Schematic representation of the preparation of surface-imprinted β-cyclodextrin-functionalized carbon nitride nanosheets. These are used, along with a molecularly imprinted polymer, for fluorometric determination of sterigmatocystin.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Sidra Naseer,Jie Ouyang,Xing Chen,Shujin Pu,Yanting Guo,Xuan Zhang,Dali Li,Chengli Yang
Nanoparticles have been successfully used for immobilization of different enzymes . The enzyme immobilized by nanomaterials has promising application in the biotechnological industry. The β-glucosidase is very important in industrial field. The immobilization of β-glucosidase by nanomaterials increases its activity and reusability. In this work, the β-glucosidase was extracted from fruiting bodies of Agrocybe aegirit and was purified by anion exchange . The β-glucosidase was immobilized by SiO 2 nanoparticles (nano-SiO 2 ) crosslink with glutaraldehyde (GA). On the other hand, the β-glucosidase firstly immobilized by process adsorption and then crosslink with genipin (GP) which was produced by the hydrolysis of geniposide by β-glucosidase. Then we compared the properties of both immobilized GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase, their immobilization yields were 83.34% and 96.29% respectively. The GA-crosslinked β-glucosidase and free β-glucosidase revealed optimal pH at 6.0. The optimal pH of GP-crosslinked β-glucosidase was ranging between 4.5 and 7.5. The GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase revealed the optimal temperature at 50 °C, 70 °C respectively. For the free β-glucosidase, the optimal temperature was 55 °C. Furthermore, the GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase were characterized by scanning electron microscope (SEM). The geniposide consumption in the reaction system of GA-crosslinked β-glucosidase was analyzed by high performance liquid chromatography (HPLC).
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危险品化学品经营许可证（带存储）