CHEMICAL PAPERS
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2017
·Vol. 71
·期 10
·1985-1992
·
IF 1.258
Fan Haiyang,Chen Lifeng,Sun Huihui,Wang Hualei,Liu Qinghai,Ren Yuhong,Wei Dongzhi
This study aimed at developing an efficient biotransformation process for phenylacetic acid production from phenylacetonitrile by using recombinant Escherichia coli M15 harboring a double mutant MG nitrilase (I113M/Y199G) from Burkholderia cenocepacia J2315. A yield of 2310 U/mL nitrilase was obtained by fermentation after the optimization of cultivation conditions, with a specific activity of 64 U/mg dcw. The MG nitrilase showed high substrate tolerance and completely hydrolyzed 100 mM phenylacetonitrile in 30 min under optimal conditions. To alleviate substrate inhibition, periodic or continuous batch-feeding of substrate was used during the biotransformation. Up to 164 g/L substrate was completely hydrolyzed in 9 h with continuous batch-feeding using resting cells, corresponding to 400 U/mL of nitrilase activity, and leading to production of 163.4 g/L phenylacetic acid. The hydrolysis process has potential application for phenylacetic acid production on a large scale.
研究领域:
生物化学
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生物工程
·
酶学
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产品关联
DOI
高影响因子
Environmental Science & Technology Letters
·
2018
·
IF 5.869
Di Zhang,Wenhai Chu,Yun Yu,Stuart W. Krasner,Yang Pan,Jun Shi,Daqiang Yin,Naiyun Gao
2-Chlorophenylacetonitrile (2-CPAN) and 3,4-dichlorophenylacetonitrile (3,4-DCPAN), representatives of a new class of nitrogenous aromatic disinfection byproducts, were first identified and quantified in chlorinated and chloraminated drinking waters. The impacts of pH, disinfectant residuals, and quenching agents on the stability of two chlorophenylacetonitriles (CPANs) were investigated. The two CPANs slightly degraded with increasing pH (5–9) and chlorination doses (0–4 mg/L) after 5 days, and NH2Cl did not cause degradation of CPANs. Among the commonly used quenching agents, the reaction between sodium sulfite and CPANs was negligible, whereas the others reduced CPANs by varying extents after 7 days. Notably, the two CPANs in finished water collected from seven drinking water treatment plants were quantified. 2-CPAN was detected between 170 and 530 ng/L with a median concentration of 220 ng/L, whereas 3,4-DCPAN ranged from below method detection limit (100 ng/L) up to 320 ng/L with a median concentration of 130 ng/L. Moreover, cytotoxicity of the CPANs and their aliphatic counterparts was determined using Chinese hamster ovary cells. The LC50 values are 133, 83, 436, 260, 905, 4150, and 8900μM for 2-CPAN, 3,4-DCPAN, chloroacetonitrile, dichloroacetonitrile, chloroacetic acid, dichloroacetic acids, and trichloromethane, respectively. Because of the relatively high stability and high toxic potencies of CPANs, the occurrence of CPANs in drinking water deserves attention.
研究领域:
环境科学
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水处理
·
毒理学
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产品关联
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Di Zhang,Tom Bond,Stuart W. Krasner,Wenhai Chu,Yang Pan,Bin Xu,Daqiang Yin
Two chlorophenylacetonitriles (CPANs) (2-chloro- and 3,4-dichlorophenylacetonitrile), representatives of an emerging class of aromatic nitrogenous disinfection byproducts , were recently identified in chlor(am)inated drinking water with liquid/liquid extraction and gas chromatography/mass spectrometry (GC/MS). Due to their high cytotoxicity, they are potentially significant drinking water contaminants. The detection limit for these two CPANs with the previous method was 100 ng L −1 . To search for additional CPAN isomers, a more sensitive method for the simultaneous determination of eight CPANs was developed using solid-phase extraction (SPE)-GC/MS. GC/MS parameters and SPE pre-concentration conditions, including SPE cartridge, eluent type, eluent volume, and sample pH, were optimized. Under optimized conditions, the new method had method detection limits, method quantification limits, and precision ranging from 0.15 to 0.37 ng L −1 , 0.50–0.95 ng L −1 , and 5.8%–11%, respectively. The recoveries of the eight CPANs ranged from 92% to 102%. The concentrations of the eight CPANs in nine finished drinking waters were determined to be at concentrations ranging from 0.5 to 155 ng L −1 . Seven CPANs were detectable in all samples. CPANs were detected at concentrations between 0.8 and 155 ng L −1 in chlorinated waters, and from 0.5 to 15 ng L −1 in chloraminated waters. Across all waters, the sum of all CPANs in chloraminated waters was 13% of that in chlorinated systems.
研究领域:
环境科学
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分析化学
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公共卫生
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产品关联
DOI
PubMed
高影响因子
RSC Advances
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2017
·Vol. 7
·期 84
·53316-53321
·
IF 3.108
Hongyu Guo,Liangbin Lin,Jiabin Qiu,Fafu Yang
Herein, three phenylacrylonitrile-bridging triphenylene dimers were prepared by condensation and etherification procedure in moderate yields. They exhibited the ordered hexagonal columnar mesophase based on the strong columnar stacking-induced action of two triphenylene units. A subtle balance between fluorescence decrease and AIE effect existed upon adding H2O to the THF solution, resulting in high fluorescence for these novel AIE liquid crystals in both solid state and solution for the first time.
研究领域:
材料科学
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光学
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产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Yulong Yang,Jiao Feng,Shicui Zhu,Jinshu Zhou,Kejia Zhang,Xiaoyan Ma,Danial Gallagher,Andrea M. Dietrich
Nitrogenous disinfection by-products (N-DBPs) are more genotoxic and cytotoxic than the currently regulated carbonaceous DBPs (i.e., C-DBPs), and it has become a frontier issue of drinking water safety research. In this paper, the effect of granular activated carbon (GAC) on adsorption and its influencing factors was investigated for a typical N-DBP phenylacetonitrile, which is produced during chlorination of phenylalanine precursor during water treatment. The results showed that GAC had a high adsorption capacity (q max = 22.92 mg/g) for phenylacetonitrile, and the adsorption isotherm was fitted to the Langmuir isotherm model. Pseudo-second-order equation can well describe the behavior of phenylacetonitrile adsorption on activated carbon (R 2 > 0.990), and the adsorption rate constant k 2 = 0.7780–14.12 g/(mg h). Analysis of the influencing factors showed that higher phenylacetonitrile concentration improved the adsorption equilibrium capacity and the adsorption rate. Water temperature and pH had little effect on the capacity or rate of adsorption.
研究领域:
环境科学
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水处理工程
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毒理学
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环境健康
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DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2023
·
IF 9.8
Mansu Yang,Di Zhang,Wenhai Chu
Microplastics (MPs) widely exist in all kinds of water bodies. The physical and chemical properties of MPs make them easy to become the carrier of pollutants, but the interaction between disinfection by-products (DBPs) and MPs has not been studied yet. In this study, the occurrence of emerging high-toxic chlorophenylacetonitriles (CPANs) in wastewater treatment plant (WWTP) effluents was determined. CPANs ubiquitously existed in WWTP effluents, and the concentration ranged from 88 ± 5 ng/L to 219 ± 16 ng/L. The typical MPs (i.e., polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS)) were selected to study their adsorption of CPANs. Adsorption kinetics and isotherm analysis were carried out. The maximum Langmuir adsorption capacities were 8.602 ± 0.849 to 9.833 ± 0.946 μg/g for PE, 13.340 ± 1.055 to 29.405 ± 5.233 μg/g for PET, and 20.537 ± 1.649 to 43.597 ± 1.871 for PS. Dichloro-CPANs had higher adsorption capacity than monochloro-CPANs. After that, the specific surface area, contact angle, FTIR spectrum, crystallinity , and glass transition temperature (Tg) of MPs were measured. Based on the analysis of the properties of both MPs and CPANs, the mechanism of adsorption was studied. The adsorption of CPANs on PE was mainly affected by pore-filling and van der Waals force . In addition to these two factors, the adsorption of PET was also affected by hydrophobic interaction. Due to the substituents on the benzene ring, there was π-π interaction between PS and CPANs, which might be the reason why PS had the highest adsorption capacity for CPANs. Finally, the effects of pH and dissolved organic matter were studied, and their effects were relatively limited. The results indicated that MPs may adsorb CPANs in actual WWTP effluents, and special attention should be paid to the possible impacts on the aquatic environment caused by the transfer of CPANs on MPs.
研究领域:
环境科学
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化学工程
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水处理
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DOI
PubMed
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2025
·
IF 1.3
Wang Chengfei,Zheng Guangbing,Jiang Shouxiang,Sun Xiangyu,Huang Xin,Xie Wenjun,Li Haoran,Jiang Xia,Wang Guan,Zheng Gengxiu
The solubility of 3,4,5-Trimethoxyphenylacetonitrile (TMB) was measured by employing a static gravimetric method in twelve pure solvents (methanol, ethanol, n -propanol, iso -propanol, n -butanol, 2-butanol, n -hexane, cyclohexane, n -heptane, ethyl acetate, iso -propyl acetate, N,N’ -dimethyl formamide (DMF)) with the temperature ranging from 283.15 to 323.15 K under the atmospheric pressure. The experimental results demonstrated that the mole fraction solubility of TMB increased with the increasing temperature in all systems, and the solubility of TMB is the highest in DMF and lowest in n-heptane. The experimental solubility of TMB was fitted using the modified Apelblat, Wilson, Yaws, and λh models. And the experimental data were agreed well with these models. Furthermore, the results show that the best fitting model was the modified Apelblat model with an average relative deviation of less than 1%. The intermolecular forces between solute and solvent were evaluated by the cohesive energy density obtained by molecular dynamics simulation, and the solubility and compatibility of solute and solvent were predicted. The analysis of Hansen solubility parameters was performed to investigate the similarities between solvents and TMB, thereby improving our understanding of their dissolution behaviors. The thermodynamic properties of the dissolution process are also calculated using the Wilson model. The results show that the dissolution of TMB is an endothermic process driven by enthalpy.
研究领域:
化学工程
·
物理化学
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产品关联
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2018
·Vol. 102
·期 14
·6047-6056
·
IF 3.34
Zhang Zhi-Jun,Cai Rui-Feng,Xu Jian-He
A nitrilase from Hoeflea phototrophica DFL-43 (HpN) demonstrating excellent catalytic activity towards benzoylacetonitrile was identified from a nitrilase tool-box, which was developed previously in our laboratory for ( R )- o -chloromandelic acid synthesis from o -chloromandelonitrile. The HpN was overexpressed in Escherichia coli BL21 (DE3), purified to homogeneity by nickel column affinity chromatography, and its biochemical properties were studied. The HpN was very stable at 30–40 °C, and highly active over a wide range of pH values (pH 6.0–10.0). In addition, the HpN could tolerate against several hydrophilic organic solvents. Steady-state kinetics indicated that HpN was highly active towards benzoylacetonitrile, giving a K M of 4.2 mM and a k cat of 170 s −1 , the latter of which is ca. fivefold higher than the highest record reported so far. A cascade reaction for the synthesis of optically pure ( S )-β-phenylalanine from benzoylacetonitrile was developed by coupling HpN with an ω-transaminase from Polaromonas sp. JS666 in toluene-water biphasic reaction system using β-alanine as an amino donor. Various ( S )-β-amino acids could be produced from benzoylacetonitrile derivatives with moderate to high conversions (73–99%) and excellent enantioselectivity (> 99% ee ). These results are significantly advantageous over previous studies, indicating a great potential of this cascade reaction for the practical synthesis of ( S )-β-phenylalanine in the future.
研究领域:
生物催化
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生物化学
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有机化学
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酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）