ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2023
·Vol. 415
·期 9
·1733-1740
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IF 4.3
Tang Kexin,Dong Jiacheng,Zheng Zhengheng,Zhang Ting,Pan Huayi,Jia Honghua,Li Yan,Wei Ping
ω-Transaminases (ω-TAs) are widely available for the production of chiral amines and unnatural amino acids. Herein, a rapid spectrophotometric method was developed for screening ω-TAs based on the colored products that can be generated from transamination reactions between aliphatic α-diketones and amino donors catalyzed by ω-TAs. The possible mechanism of the formation of the colored product was investigated according to LC-Q-TOF–MS analysis. Among seven diketones, 2,3-butanedione was selected as the most suitable amino acceptor for colorimetric screening of ω-TAs with high efficiency, high sensitivity, and low background interference. Meanwhile, the absorbance of the colored product generated by 2,3-butanedione catalyzed by ω-TAs in this method was linearly correlated with the results by HPLC analysis. This method was also confirmed to effectively screen ω-TA mutants with high activity towards isopropylamine. Graphical Abstract
研究领域:
生物化学
·
酶工程
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DOI
PubMed
高影响因子
HYDROMETALLURGY
·
2021
·
IF 4.156
Licheng Zhang,Lianmin Ji,Lijuan Li,Dong Shi,Taoshan Xu,Xiaowu Peng,Xuexue Song
A method of recovering cobalt, nickel, and lithium from mixed solutions was proposed based on β-diketone solvent extraction using benzoyltrifluoroacetone (HBTA), trioctylphosphine oxide (TOPO), and green kerosene. The effective metal recovery and separation parameters such as solution pH, saponification degree, extraction time, and phase ratio were evaluated experimentally. The results indicated that cobalt and nickel were recovered through 2-stage cross-current extraction at different phase ratios and that lithium was recovered through three-stage countercurrent extraction. The metal-loaded organic phase was stripped using an inorganic acid solution to obtain cobalt-, nickel-, and lithium-concentrated solutions. The Co/Ni and Ni/Co molar ratios in the cobalt- and nickel-concentrated solutions were 54.4 and 164, respectively, and the lithium concentration reached 1.78 × 10 4 mg L −1 in the lithium-enriched solution. The extraction mechanism was studied, and the results revealed that Co 2+ and Ni 2+ were extracted by ion exchange in which two moles of H + or Na + had been replaced by divalent metal ions . The Li + extraction stoichiometry was studied by cultivating single crystals. Because cobalt, nickel, and lithium were recovered by single extraction, no other organic substances were required. This work provides a sustainable, environmentally friendly, and versatile method of recovering valuable metals from spent lithium batteries .
研究领域:
化学工程
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环境科学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2013
·
IF 3.172
Yan Zhao,Bing Yan
GaN-functionalized rare earth (Eu 3+ and Tb 3+ ) organic/inorganic mesoporous nanocomposites have been successfully synthesized (designated as RE(L SBA-15) 3 (L GaN); RE = Eu, Tb; L = TAA Si, BTA Si). The organosilane precursor materials (L SBA-15) are synthesized by co-condensation of tetraethylorthosilicate (TEOS) and the functionalized β-diketones (TAA Si and BTA Si) in the presence of Pluronic P123 surfactant as a template. The modified β-diketones ligands are also used to covalently bond with surface-modified GaN and formed another precursor L GaN. Both of the precursors can coordinate with rare earth ions to synthesize the final mesoporous materials via a sol–gel process. FTIR, TEM, XRD, and nitrogen (N 2 ) adsorption/desorption measurements are employed to characterize the mesostructure of RE(L SBA-15) 3 (L GaN). The luminescence properties and thermogravimetric analysis of all the prepared materials are characterized in detail, and the results reveal that a series of uniformed mesopore structure hybrid materials has been achieved. The mesoporous material Eu(BTA Si SBA-15) 3 (BTA Si GaN) has better luminescence intensity, higher quantum efficiency, and longer lifetime than Eu(TAA Si SBA-15) 3 (TAA Si GaN). While the nanocomposite Tb(TAA Si SBA-15) 3 (TAA Si GaN) revealed the strongest characteristic emission of Tb 3+ ions than Tb(BTA Si SBA-15) 3 (BTA Si GaN), the excellent luminescent properties and thermal stability enable the hybrid mesoporous material to have potential applications in optical field.
研究领域:
材料科学
·
化学
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产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2023
·
IF 4.1
Ning Shi,Tianlang Zhu,Hongyan Zhang,Hongsheng Huang,Liang Zhou,Ying Liu,Riyang Shu
Catalytic conversion of cellulose into the novel platform molecule 2,5-hexanedione (HXD) is regarded as one feasible approach for high-value utilization of biomass resources. Here, we reported one efficient way of one-pot conversion of cellulose into HXD with high yield of 80.3% in H2O and tetrahydrofuran (THF) mixture within Al2(SO4)3 combined with Pd/C as a catalyst. In the catalytic reaction system, Al2(SO4)3 could catalyze the conversion of cellulose into 5-hydroxymethylfurfural (HMF), and Pd/C combined with Al2(SO4)3 could catalyze the hydrogenolysis of HMF into furanic intermediates such as 5-methylfurfuryl alcohol and 2,5-dimethylfuran (DMF) without causing over-hydrogenation of these furanic intermediates. These furanic intermediates were finally transformed into HXD catalyzed by Al2(SO4)3. Besides, the H2O/THF ratio could significantly influence the reactivity of the hydrolytic furanic ring-opening of the furanic intermediates. The catalytic system also showed excellent performance on the conversion of other carbohydrates (glucose and sucrose) into HXD.
研究领域:
生物质化学
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催化反应工程
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DOI
PubMed
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2022
·Vol. 106
·期 7
·2403-2414
·
IF 5.56
Zhao Wenyu,Xie Haisheng,Zhang Xuehong,Wang Zhilong
Abstract Water–oil interface of bacterial cell-stabilized Pickering emulsions is an exceptional habitat for microbial assimilation of both hydrophobic nutrients solubilized in oil phase and hydrophilic ones solubilized in water phase. Crystal substrate inhibition, i.e., decreasing phytosterol degradation with the increase loading of crystal phytosterols, is always observed during microbial transformation of phytosterols into steroid synthons in Mycolicibacterium sp (China Center of Industrial Culture Collection, CICC 21,097) cell-stabilized Pickering emulsions. In the present work, we confirmed that crystal substrate inhibition was attributed to the interaction between M. neoaurum and phytosterol crystals that led to the detachment of bacterial cells from the oil–water interfaces in bacterial cell-stabilized Pickering emulsions. Under the selected operation condition (25 ml BEHP per 40 ml water, 60 g/L glucose, 25 g/L phytosterols), the product androst-4-ene-3, 17-dione (AD) and androsta-1, 4-dien-3, 17-dione (ADD) concentration increased linearly with the progress of microbial transformation and reached almost 6 g/L at the 11 th day. This is a paradigm for microbial transformation of crystal substrates as well as in the presence of other surface active additives (such as chitosan and nonionic surfactants) in bacterial cell-stabilized Pickering emulsions. Key points • Microbial transformation of crystal phytosterols in Pickering emulsions • Crystal substrate inhibition occurring during microbial transformation • Interaction between phytosterol crystals and bacterial cells leading to demulsification
研究领域:
生物技术
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微生物学
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化学工程
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药学
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DOI
PubMed
高影响因子
ACS Infectious Diseases
·
2024
·
IF 4
Jing Wu,Yong Zhang,Wenqi Li,Hao Tang,Ying Zhou,Di You,Xiaohe Chu,Hanbing Li,Jinsai Shang,Nan Qi,Bang-Ce Ye
Cholesterol is a key carbon source for Mycobacterium tuberculosis (Mtb) survival and persistence within macrophages. However, little is known about the role of cholesterol metabolism by Mtb in host–Mtb interplay. Here, we report the immune suppression mediated by Mtb’s cholesterol metabolites. Conducting the cholesterol metabolic profiling and loss-of-function experiments, we show that the cholesterol oxidation products catalyzed by a thiolase FadA5 from Mtb H37Ra, 4-androstenedione (AD), and its derivant 1,4-androstenedione (ADD) inhibit the expression of pro-inflammatory cytokines and thus promote bacterial survival in bone marrow-derived macrophages (BMDMs). Our time-resolved fluorescence resonance energy transfer (TR-FRET)-based screening further identifies the nuclear receptor LXRα as the target of ADD. Activation of LXRα via ADD impedes the nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPK) signaling and reduces cholesterol accumulation in lipid rafts upon TLR4 simulation, thereby compromising the inflammatory responses. Our findings provide the evidence that Mtb could suppress the host immunity through its cholesterol metabolic enzyme and products, which are potential targets for screening novel anti-tuberculosis (TB) agents.
研究领域:
微生物学
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免疫学
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传染病
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代谢
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产品关联
DOI
PubMed
高影响因子
HYDROMETALLURGY
·
2017
·
IF 2.605
Licheng Zhang,Lijuan Li,Dong Shi,Xiaowu Peng,Fugen Song,Feng Nie,Wensheng Han
Lithium recovery from alkaline brines by counter-current method using β-diketone was investigated. By comparing effect of different co-extractants and diluents on lithium extraction, HBTA-TOPO-kerosene system was determined as the extraction system. In extraction process, 0.4 mol/L HBTA and 0.3 mol/L TOPO in kerosene performed as extractant and three theoretical stages were required to reach 95% extraction according to McCabe Thiele diagram. 1 mol/L HCl and 3 mol/L HCl solution were used as scrubbing agent and stripping agent respectively. In regeneration stage, 2 mol/L NaOH was used as regeneration agent to remove free acid entrained in organic phase and exchange H + of hydroxyl. Bench experiments indicated that the respective number of extraction, scrubbing, stripping and regeneration were 3, 1, 2 and 1 stage. A 7-stage extraction process was conducted in a mixer-settler for 30 h to reach stable state, average extraction rate of lithium was 96% and lithium concentration in stripping solution was 15 g/L. Concentration of impurity ions in stripping liquor was < 1 g/L. No third phase or emulsification was observed during the operation. In summary, HBTA-TOPO-kerosene extraction system was verified an effective method to recovery lithium from alkaline brine.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shen Wang,Meng Rong,Lin-Bing Sun,Yunze Zhao,Huifang Xing,Liangrong Yang
Indeed, the efficient and sustainable recovery of lithium from highly concentrated sodium-containing mother liquors of Li 2 CO 3 and salt-lake brines remains a significant challenge. Herein, two typical Li + recognition receptors, namely benzo-12-crown-4 and thenoyltrifluoroacetone, were separately introduced into the cationic and anionic parts to successfully synthesize novel bi-functionalized task-specific ionic liquids [(B12C4)C n im][TTA] (n = 4, 6, 8). A new, green, and high-efficiency extraction system has been developed by dissolving [(B12C4)C 6 im][TTA] in commercial room-temperature ionic liquid 1-hexyl-3-methyl-imdazolium bis(trifluromethylsulfonyl)imide [C 6 mim][NTf 2 ], without the addition of any other co-extractants. The newly developed [(B12C4)C 6 im][TTA]-[C 6 mim][NTf 2 ] extraction system exhibited a wide pH working range (4.0–11.0), high lithium extraction efficiency (95.4 %), as well as superior separation factors of Li/Na (β Li/Na = 2154.0) and Li/K (β Li/K =757.2). The extraction mechanism involving cation exchange was determined through slope analysis, ion chromatography, UV–vis spectroscopy and FT-IR spectra measurement, indicating that one [(B12C4)C 6 im][TTA] molecule can interact with two lithium ions and form a 1:2 complex. Moreover, the [(B12C4)C 6 im][TTA]-[C 6 mim][NTf 2 ] extraction system also demonstrated fast extraction kinetics, facile stripping and regeneration, along with good cycling performance. Furthermore, a multi-stage countercurrent extraction process to extract lithium from the simulated mother liquor of Li 2 CO 3 was evaluated. When the volume ratio (O/A) of oil phase (O) to water phase (A) was 1.0, only two theoretical extraction stages were needed to extract 91.4 % of lithium into the organic phase. Thus, the [(B12C4)C 6 im][TTA]-[C 6 mim][NTf 2 ] extraction system is promising for lithium extraction from mother liquor of Li 2 CO 3 and salt-lake brines. This study also opens the avenue for designing cationic and anionic bi-functionalized ionic liquids for metal ion separation.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2014
·
IF 3.209
Bing Yan,Qiu-Ping Li
Several kinds of novel lanthanide organic–inorganic mesoporous hybrid luminescent materials have been assembled by introducing the ternary lanthanide ions (Eu 3+ , Tb 3+ ) and beta-diketone (TTA, TAA) into the functionalized mesoporous hosts through the coordination bond and covalent bond by using 3-chloropropyltriethoxysilane modified 1,4,7,10-tetraazacyclododecane (Cyclen-Si) as an organic bridge molecule. These multicomponent hybrids are characterized by FTIR, TEM, XRD, thermogravimetric analysis, diffuse reflectance UV–Vis spectra and nitrogen adsorption–desorption isotherms, especially the photoluminescence properties of them. The luminescent spectra of the hybrids reveal that the MCM-41 based materials show strong emission intensities, high luminescent quantum efficiencies, long luminescent lifetimes and exhibit characteristic red and green luminescence originated from lanthanide ions (Eu 3+ or Tb 3+ ), which suggesting the Cyclen-Si bridge molecule is favorable for the assembly of lanthanide functionalized luminescent hybrids.
研究领域:
材料科学
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光化学
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产品关联
DOI
高影响因子
CHIRALITY
·
2013
·Vol. 25
·期 10
·656-662
·
IF 1.894
Yangmin Ma,Hao Wu,Jin Zhang,Yanchao Li
A series of single isomers tetrahydro- β -carboline diketopiperazines were stereoselectively synthesized starting from l -tryptophan methyl ester hydrochloride and six aldehydes through a four-step reaction including Pictet-Spengler reaction, crystallization-induced asymmetric transformations (CIAT), Schotten-Baumann reaction, and intramolecular ester amidation. The chemical structures were characterized by nuclear magnetic resonance (NMR) and elemental analysis, among which two compounds were determined by x-ray single crystal diffraction. Moreover, antimicrobial activities of all the compounds were also tested. Chirality 25:656–662, 2013 . © 2013 Wiley Periodicals, Inc.
研究领域:
有机化学
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药物化学
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微生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2018
·
IF 2.732
Siqi Fan,Xu Yao,Jingfang Li,Weizuo Li,Guangming Li
In view of the potential application of NIR luminescence in biology, a series of four new 3,5-Heptanedione (β-diketonate) ytterbium complexes, e.g. [Yb(L) 3 (H 2 O) 2 ] ( 1 ), [Yb(L) 3 (2,2′-bpy)] ( 2 ), [Yb(L) 3 (dpq)] ( 3 ) and [Yb(L) 3 (dppz)] ( 4 ) have been designed and isolated. Crystal structures analysis show that all complexes 1 – 4 exhibit the similar mononuclear structure, in which the central Yb 3+ ion is eight-coordinated forming the square-anti-prismatic geometry. NIR luminescence of all complexes 1 – 4 shows strong characteristic emission of Yb 3+ ions. To improve the mechanical and thermal stability, complex 1 was further doped into poly-(methyl methacrylate) (PMMA) for preparing a thin film ( 1 @PMMA). Their thermal stability and NIR luminescence were essentially enhanced in contrast to that for complex 1 . This NIR luminescent thin film may be of potential applications in biological dictation and luminescent probe.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Jian Zhang,Yahui Liu,Wensen Liu,Lina Wang,Jing Chen,Zhaowu Zhu,Tao Qi
The synergisms of β-diketone and phosphine oxide are very efficient for lithium selective extraction from alkaline systems, and have been obtained wide applications, especially for lithium recovery from salt lake brines. However, the systems are ready to form emulsification which seriously impacted their practical applications. In this study, the synergistic mechanism of β-diketone and phosphine oxide was intensively studied using a typical β-diketone of HTTA (2-Thenoyltrifluoroacetone) and TOPO (Trioctylphosphine oxide) through extraction parameter relationships, FT-IR measurements, structure computational simulations. It is found that one molar water readily presented in the extracted species forming Li·(H 2 O)·TTA·TOPO, while two molar water presented when HTTA alone was used which more readily forms emulsification or even solid. When TOPO was attended, one molar of water was replaced by it as there is an unconfirmed “boundary“ formed between them which will significantly mitigate the emulsification formation.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）