BIOCHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 4.446
He Li,Dongbang Yao,Jingru Ying,Xudong Han,Xuecheng Zhang,Xiuju Fang,Zemin Fang,Yazhong Xiao
A strategy that combines signal peptide (SP) optimization and translation efficiency improvement was used to enhance the extracellular production of raw starch-degrading α-amylase AmyZ1 from Pontibacillus sp. ZY in Bacillus subtilis . The optimal SP YpuA screened from 173 B. subtilis SPs mediated a 1.28-fold higher AmyZ1 activity than the original SP amyQ . Then, strategies of translation efficiency improvement, including optimizing the Shine-Dalgarno-like (SD-like) sequence, constructing a dual 5′-untranslated region (dual-UTR), optimizing the spacer region of the UTR, and optimizing the 5′-proximal coding sequence, were used to enhance AmyZ1 production. The resulting recombinant strain (BZYACO6) containing SD-like3, dUTR2, and an optimized 5′-proximal coding sequence (O6) produced the highest extracellular α-amylase activity of 2974.0 U/mL in shake flask, 2.07-fold higher than that of the original strain BZd34 (1437.6 U/mL). After fermentation optimization, the BZYACO6 strain produced an extracellular AmyZ1 activity of 3915.2 U/mL in shake flask and 25,070 U/mL in 3-L fermenter, representing the highest level of recombinant raw starch-degrading α-amylase production reported to date. Furthermore, this work provides a strategic reference for enhancing the extracellular production of other recombinant proteins in B. subtilis .
研究领域:
微生物学
·
生物技术
·
酶学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Shuaifeng Liu,Edouard Asselin,Zhibao Li
An industrially feasible process was proposed to produce α-calcium sulfate hemihydrate (α-HH) from FGD gypsum without any additives. In this process, an AlCl3 solution was used to promote the conversion of calcium sulfate dihydrate (DH) to hexagonal prismatic α-HH with high strength at atmospheric pressure. The phase transition kinetics of FGD gypsum was experimentally investigated under conditions: AlCl3 (2–2.5 m), MgCl2 (0–0.4 m) existing in raw FGD gypsum, and the solid–liquid ratio (or solid content %) range of 0.1–2 at 363 K. It was found that increasing the concentrations of MgCl2 in AlCl3 solution accelerated the conversion. The uniform large hexagonal prism HH product was obtained at the folowing optimal conditions: 2.5 mol/kg AlCl3, 0.4 mol/kg MgCl2, solid–liquid ratio of 2, and equilibration time of 2 h at 363 K. The phase diagram of the AlCl3-MgCl2-H2O system was determined by measuring solubility of solids. The E-NRTL activity model was used to construct the phase transition diagram of CaSO4 in AlCl3–MgCl2 media and to judge the stable range of DH and HH.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
MOLECULES
·
2021
·Vol. 26
·期 15
·4472
·
IF 4.412
Rurui Li,Yuerong Ru,Zhenxing Wang,Xiahong He,Kin-Weng Kong,Tingting Zheng,Xuechun Zhang
In this study, we aimed to investigate the chemical components and biological activities ofMusella lasiocarpa, a special flower that is edible and has functional properties. The crude methanol extract and its four fractions (petroleum ether, ethyl acetate, n-butanol, and aqueous fractions) were tested for their total antioxidant capacity, followed by their α-glucosidase, acetylcholinesterase, and xanthine oxidase inhibitory activities. Among the samples, the highest total phenolic and total flavonoid contents were found in the ethyl acetate (EtOAc) fraction (224.99 mg GAE/g DE) and crude methanol extract (187.81 mg QE/g DE), respectively. The EtOAc fraction ofMusella lasiocarpaexhibited the strongest DPPH· scavenging ability, ABTS·+scavenging ability, and α-glucosidase inhibitory activity with the IC50values of 22.17, 12.10, and 125.66 μg/mL, respectively. The EtOAc fraction also showed the strongest ferric reducing antioxidant power (1513.89 mg FeSO4/g DE) and oxygen radical absorbance capacity ability (524.11 mg Trolox/g DE), which were higher than those of the control BHT. In contrast, the aqueous fraction demonstrated the highest acetylcholinesterase inhibitory activity (IC50= 10.11 μg/mL), and the best xanthine oxidase inhibitory ability (IC50= 5.23 μg/mL) was observed from the crude methanol extract as compared with allopurinol (24.85 μg/mL). The HPLC-MS/MS and GC-MS analyses further revealed an impressive arsenal of compounds, including phenolic acids, fatty acids, esters, terpenoids, and flavonoids, in the most biologically active EtOAc fraction. Taken together, this is the first report indicating the potential ofMusella lasiocarpaas an excellent natural source of antioxidants with possible therapeutic, nutraceutical, and functional food applications.Keywords:Musella lasiocarpa;antioxidant activity;α-glucosidase;xanthine oxidase;acetylcholinesterase;HPLC-MS/MS;GC-MS
研究领域:
植物化学
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药理学
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营养学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CELLULAR AND MOLECULAR MEDICINE
·
2020
·Vol. 24
·期 23
·13690-13702
·
IF 4.486
Yi Jiang,Hanjun Qin,Haoyang Wan,Jun Yang,Qi Yu,Mo Jiang,Bin Yu
Our laboratory originally synthesized strontium(Sr)-containing α-calcium sulphate hemihydrate/nano-hydroxyapatite composite (Sr-α-CSH/n-HA) and demonstrated its ability to repair critical bone defects. This study attempted to incorporate aspirin into it to produce a better bone graft material for critical bone defects. After 5% Sr-α-CSH was prepared by coprecipitation and hydrothermal methods, it was mixed with aspirin solution of different concentrations (50 μg/ml, 200 μg/ml, 800 μg/ml and 3200 μg/ml) at a fixed liquid-solid ratio (0.54 v/w) to obtain aspirin-loaded Sr-α-CSH/n-HA composite. In vitro experiments were performed on the composite extracts. The tibial defects (3 mm*5 mm) in SD rat model were filled with the composite for 4 weeks and 12 weeks to evaluate its osteogenic capacity in vivo. Our results showed its capability of proliferation, migration and osteogenesis of BMSCs in vitro got improved. In vivo treatment with 800 μg/ml aspirin–loaded Sr-α-CSH/n-HA composite led to significantly more new bone formation in the defects compared with Sr-α-CSH/n-HA composite and significantly promoted the expression of osteogenic-related genes and inhibited osteoclast activity. In general, our research suggests that aspirin-loaded Sr-α-CSH/n-HA composite may have a greater capacity of repairing tibial defects in SD rats than simple Sr-α-CSH/n-HA composite.
研究领域:
生物材料学
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骨组织工程
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药理学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2021
·
IF 4.354
Yuxiu Li,Xiangqian Li,Xiaowei Li,Dayong Shi
The straightforward synthesis of α-fluoro-β-arylalkenyl sulfones under transition-metal- and base-free conditions has been described, which displays broad functional group compatibility and high stereoselectivity. In particular, the strategy is also applied to the late-stage modification of complex natural products and drugs.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 46
·23607-23620
·
IF 7.443
Zhifeng Jiang,Deli Jiang,Wei Wei,Zaoxue Yan,Jimin Xie
In this work, we fabricated size-tunable metal (Pd, Ag) nanoparticles grafted on bionic dendritic α-Fe2O3 (M@Fe2O3) through an in situ growth method by using carbon nanodots as a reducing agent followed by a hydrothermal reaction. The size of the supported noble metal nanoparticles can be directly controlled on the surface of dendritic α-Fe2O3 by adjusting the added amount of noble metal salts. The catalytic performances of the resulting M@Fe2O3 hybrid composites were firstly evaluated by reduction of p-nitrophenol. The results indicated that the size of the noble metal nanoparticles had a crucial influence on the catalytic behaviors of the M@Fe2O3. In addition, the dendritic M@Fe2O3 also showed improved photocatalytic efficiencies for visible-light-driven MB degradation due to synergic effects between dendritic α-Fe2O3 and noble metal nanoparticles, including optical properties, unique structure, good dispersion, good charge separation and the SPR effect. The M@Fe2O3 composites have good reproducibility and are highly stable for p-nitrophenol reduction/degradation of MB. Our strategy can be extended to a general strategy for the formation of other novel composites consisting of a 3D hierarchical metal oxide and noble metal nanoparticles with tailorable size (e.g., Pt@TiO2, Pd@MnO2, Au@ZnO and Ag@Cu2O) for broad applications in water treatment.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Mingjun Sun,Kuan Ding,Yujie Lu,Xiaopeng She,Yi Chen,Mengqing Wang,Cheng Zou,Xiaoyu Liu,Yong Zhou
Of diverse NH 3 gas-detection strategies applied in the fields of individual healthcare and industrial production, chemiresistive gas sensors gain the most popularity owing to the superior merits of low cost, convenient signal processing and high sensitivity. However, severe challenges still exist such as elevated operation temperature (>200 °C), limited sensitivity and unsatisfactory selectivity especially under low-concentration and high-humidity conditions. To overcome these hindrances, a sensing layer of black phosphorus nanosheets (BP)-modified α-MoO 3 nanoflakes was prepared in this work. After subtle optimization of ingredient composition and operation temperature, the composite sensor S2 could recognize NH 3 gas with the concentration spanning from 0.4 to 25 ppm at 40 °C. In particular, a larger mean response (27 % vs. ∼ 2.3 %) with a response/recovery speed of 275/388 s toward 10 ppm NH 3 and lower detection of limit (LoD, 0.4 ppm vs. 10 ppm) was achieved with respect to pure BP counterpart. In addition, excellent repeatability, selectivity, long-term stability and humidity-tolerant features were demonstrated for Sensor S2 . The improved sensing performance after α-MoO 3 incorporation was primarily ascribed to abundant p-n heterojunctions, excellent conductivity of BP and hydrophilic MoO 3 that mitigated the water corrosion effect on susceptible BP nanosheets. This work offers an alternative strategy for sensitive and low-temperature NH 3 detection, and well cater for the demanding requirements of high sensitivity and low-power consumption in the field of novel gas sensors applicable in the future Internet of Things and exhaled breath-oriented medical diagnosis.
研究领域:
材料科学
·
化学传感
·
生物医学工程
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 21
·6384-6397
·
IF 6.177
Zhi Zhu,Reeti Kumar,Liwen Luo,Sunita Varjani,Pengwei Huo,Jonathan Woon-Chung Wong,Jun Zhao
Photocatalytic degradation of pharmaceuticals in the aquatic environment is considered a promising strategy to address water pollution. In this study, a novel photocatalyst was constructed by decorating g-C3N4 (CN) with α-MoC1−x quantum dots (α-MoC1−x-QDs) through a facile calcination method. The catalyst showed enhanced tetracycline (TC) degradation performance under visible light. The unique Mo–N surface bonding states and quantum effect leading to superior TC degradation activity (89.1%) compared to pure CN (21.8%) were reported and revealed. More importantly, the mechanism for the significant enhancement of photocatalytic activity of the catalyst was investigated by DFT (density functional theory) calculations and photo-electrochemistry measurements. The results confirmed that the effect of α-MoC1−x-QDs on CN improved the light absorption capacity obviously, and the Mo–N surface bonding states accelerated the charge migration from CN to α-MoC1−x-QDs. Moreover, the TC degradation pathway, intermediates and photogenerated carrier transfer behaviors were also discussed in depth. This research provides a new strategy for the construction of noble-metal-free co-catalyst/semiconductor composite materials in the photocatalytic degradation of antibiotics.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2020
·
IF 3.442
Deqiang Feng,Jie He,Lingcheng Zheng,Wenjun Jiang,Ce Zhang,Long Li,Jian Song,Wei Yao
Developing novel catalysts and catalysis processes are highly attractive in environmental protection and energy utilization. Photocatalysis-Fenton combinational process is an environmentally friendly technology and has broad application prospects. In this work, thin Fe@α-Fe 2 O 3 nanosheets with thickness of 2–5 nm were designed by oxidation of Fe metal nanostructure synthesized using a modified solution reaction method. The nanosheet structure with thin thickness has short diffusion distance for the photogenerated carriers and prolongs the carriers' life. Simultaneously, the presence of Fe can reduce the resistance of system and further promote the transport and transfer of photogenerated carriers from the bulk to the surface, causing less carrier recombination and better photocatalytic performance. What's more, the Fe@α-Fe 2 O 3 composite can induce the Fenton-like reaction to generate active • OH radicals, which significantly improve the degradation rate . The synergistic effect of photocatalysis and Fenton processes makes the system show an enhanced photodegradation performance: 96.5% of RhB is degraded after 60 min visible light irradiation , especially, 84.3% of RhB is degraded within the first 10 min, which are much higher than that of the pure α-Fe 2 O 3 sample. This work demonstrates that the conjunction of photocatalysis and Fenton processes based on the Fe@α-Fe 2 O 3 nanosheets provides a potential application for pollutants degradation.
研究领域:
环境化学
·
材料科学
·
催化化学
·
纳米科技
·
物理化学
✓ 已验证
DOI
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
·
2017
·Vol. 15
·期 16
·3427-3434
·
IF 3.564
Dan Wang,Kuan Zhang,Luhan Jia,Danting Zhang,Yue Zhang,Yujia Cheng,Chang Lin,Bo Wang
Presented here is the first example of synthesizing an array of primary-, secondary-, and tertiary-α-ketoamides with a non-metal catalyst nBu4NI from methyl ketones and inexpensive readily available amine/ammonium salts; the reactions proceeded smoothly under mild conditions, TBHP was used as an oxidant and the corresponding α-ketoamides were afforded in moderate to excellent yields.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2024
·
IF 3.3
Nan Wang,Yuanyuan Huang,You Zi,Mengke Wang,Weichun Huang
A practical and regioselective direct N-alkylation of 2-pyridones is enabled by use of α-keto esters in the P(NMe2)3-mediated deoxygenation process. The reaction proceeds under mild conditions to produce N-alkylated 2-pyridones with high selectivity and generality, and the protocol is shown to be applicable for the scale-up synthesis, which makes it promising for practical applications.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
Materials Chemistry Frontiers
·
2021
·Vol. 5
·期 18
·7032-7040
·
IF 6.482
Xiaojia Jiang,Mingsong Zang,Fei Li,Chunxi Hou,Quan Luo,Jiayun Xu,Junqiu Liu
Recently, biological nanopore-based techniques have attracted more and more attention in the field of single-molecule detection because they allow real-time, sensitive, high-throughput analysis. Herein, we report an engineered biological nanopore sensor by introducing a macrocyclic host molecule carboxylatopillar[5]arene (CP[5]A) that acts as an aptamer into the lumen of a mutant (E111R/K147R)7 αHL nanopore for detecting highly toxic paraquat (PQ) via host–guest interactions at the single-molecule level. By taking advantage of introducing positively charged arginine (Arg) into the lumen of the αHL nanopore, our engineered nanopore sensor exhibits higher stability. More importantly, this nanopore sensor shows high sensitivity, and the limit of detection (LOD) for PQ can reach a nanomolar level of 0.37 ppb. The CP[5]A-based nanopore sensing strategy developed in this work may bring inspiration for single-molecule detection and hold great potential in public health applications.
研究领域:
纳米技术
·
分析化学
·
生物技术
·
毒理学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）