JOURNAL OF MOLECULAR LIQUIDS
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2021
·
IF 6.165
Ting Huang,Huang-xian Zhang,Xiao-hua Zhang,Da-yong Peng,Xu-liang Nie,Jing Chen,Wan-ming Xiong
A kind of functionalized diallylimidazole ionic liquids (CnDAIMF) was synthesized and applied in the dehydration of D-fructose to produce 5-HMF under the microwave radiation. The results showed that X-ray, 1 H NMR and FT-IR confirmed the production. The target ILs existed in a highly centrally symmetric, and crystalline state at room temperature, with a good thermal stability up to 300 °C (HTD ≥ 340 °C). In the experiments of conversion D-fructose to 5-HMF, 5-HMF could be obtained via the catalysis of diallylimidazole IL whether in water or DMSO. The catalytic performance of these ILs was not much different from that of solid acid (like camphor sulfonic acid or solid carbon sulfonic acid), and which was higher than that of the monoimidazole hexafluorophosphate or imidazole class bromine salt, but there were no obvious changes can be found with the variation of carbon chain length between imidazole rings in diallylimidazole IL. The effects of temperature and solvent on the reaction were more significant. The optimized yield of 5-HMF was 52.59% at 185 °C in a water-C 2 DAIMF solvent (t = 10 min), while 73.71% at 195 °C in DMSO-C 2 DAIMF solvent. Furthermore, six CnDAIMF have a considerable effect on the conversion in water and 5-HMF yield of about 50% could be obtained, which is satisfactory compared with other similar processes, especially in the microwave system of aqueous solution. Therefore, this process may be benefit for many researches and applications related to functionalized ionic liquid research and biomass conversion applications.
研究领域:
化学工程
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生物质能
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绿色化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2022
·Vol. 46
·期 11
·15722-15732
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IF 4.672
Yu Bai,Wenjuan Qiu,Shuangfeng Wang
Summary At present, there are few kinds of phase change materials that suitable for medium temperature heat storage. Among them, sugar alcohols have broad application prospects in the heat storage at medium temperature due to their suitable phase transition temperature. In this work, eutectic phase change material (PCM) was prepared with D-mannitol as PCM and KBr as melting point modifier. Expanded graphite (EG) was used as thermally conductive support network to prepare shape-stable composite phase change material (CPCM). The prepared CPCM—10% EG/PCM has an appropriate phase transition temperature (136.88°C), high phase melting enthalpy (215.7 J/g), and good photothermal conversion (81.9%). The thermal conductivity of 10% EG/PCM reached 6.01 W/(m K), which is approximately 10 times higher than D-mannitol (0.603 W/(m K)). Because of its excellent thermal properties, the applications of CPCM in energy storage and photothermal conversion can be further broadened.
研究领域:
材料科学
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能源存储
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太阳能利用
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF BIOTECHNOLOGY
·
2024
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IF 4.1
Yufeng Zhou,Xiaolong Sun,Jiahuan Hu,Yingjie Miao,Xiangyu Zi,Xi Luo,Yongqian Fu
Serving as a vital medical intermediate and an environmentally-friendly preservative, D-PLA exhibits substantial potential across various industries. In this report, the urgent need for efficient production motivated us to achieve the rational design of lactate dehydrogenase and enhance catalytic efficiency . Surprisingly, the enzymatic properties revealed that a mutant enzyme , Lr LDH T247I/D249A/F306W/A214Y ( Lr LDH-M 1 ), had a viable catalytic advantage. It demonstrated a 3.3-fold increase in specific enzyme activity and approximately a 2.08-fold improvement of K cat . Correspondingly, molecular docking analysis provided a supporting explanation for the lower K m and higher K cat /K m of the mutant enzyme. Thermostability analysis exhibited increased half-lives and the deactivation rate constants decreased at different temperatures (1.47–2.26-fold). In addition, the mutant showed excellent resistance abilities in harsh environments, particularly under acidic conditions. Then, a two-bacterium ( E. coli /pET28a- lrldh -M 1 and E. coli /pET28a- ladd ) coupled catalytic system was developed and realized a significant conversion rate (77.7%) of D-phenyllactic acid, using 10 g/L L-phenylalanine as the substrate in a two-step cascade reaction.
研究领域:
生物化学
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酶工程
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产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2020
·Vol. 25
·期 23
·5778
·
IF 3.267
Yangke Wanyan,Xixi Xu,Kehang Liu,Huidan Zhang,Junai Zhen,Rong Zhang,Jumei Wen,Ping Liu,Yuqing Chen
Inhibition of the glycolytic pathway is a critical strategy in anticancer therapy because of the role of aerobic glycolysis in cancer cells. The glycolytic inhibitor 2-Deoxy-d-glucose (2-DG) has shown potential in combination with other anticancer agents. Buforin IIb is an effective antimicrobial peptide (AMP) with broad-spectrum anticancer activity and selectivity. The efficacy of combination treatment with 2-DG and buforin IIb in prostate cancer remains unknown. Here, we tested the efficacy of buforin IIb as a mitochondria-targeting AMP in the androgen-independent human prostate cancer cell line DU145. Combining 2-DG with buforin IIb had a synergistic toxic effect on DU145 cells and mouse xenograft tumors. Combination treatment with 2-DG and buforin IIb caused stronger proliferation inhibition, greater G1 cell cycle arrest, and higher apoptosis than either treatment alone. Combination treatment dramatically decreased L-lactate production and intracellular ATP levels, indicating severe inhibition of glycolysis and ATP production. Flow cytometry and confocal laser scanning microscopy results indicate that 2-DG may increase buforin IIb uptake by DU145 cells, thereby increasing the mitochondria-targeting capacity of buforin IIb. This may partly explain the effect of combination treatment on enhancing buforin IIb-induced apoptosis. Consistently, 2-DG increased mitochondrial dysfunction and upregulated Bax/Bcl-2, promoting cytochrome c release to initiate procaspase 3 cleavage induced by buforin IIb. These results suggest that 2-DG sensitizes prostate cancer DU145 cells to buforin IIb. Moreover, combination treatment caused minimal hemolysis and cytotoxicity to normal WPMY-1 cells. Collectively, the current study demonstrates that dual targeting of glycolysis and mitochondria by 2-DG and buforin IIb may be an effective anticancer strategy for the treatment of some advanced prostate cancer.Keywords:buforin IIb;2-Deoxy-d-glucose;mitochondria;glycolysis;prostate cancer
研究领域:
肿瘤学
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分子生物学
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癌症治疗
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产品关联
DOI
PubMed
高影响因子
Drug Design Development and Therapy
·
2020
·
IF 3.216
Hongfang Li,Yunyan Tang,Yang Wang,Weipeng Wei,Chengchen Yin,Fushang Tang
Background Bupleurum is one of the most important traditional Chinese medicines and an ingredient in many compound preparations. It is widely used together with other drugs in clinical practice, and thus there is great potential for drug–drug interactions. Saikosaponin D (SsD) is a major bioactive triterpenoid saponin extracted from Bupleurum with anti-inflammatory, anticancer, antioxidative, and antihepatic fibrosis effects. Effects of the main components of Bupleurum on cytochromes P450 (CYPs) need to be clarified in the clinical application of combination therapies of formulations containing SsD or Bupleurum . Purpose This study aimed to investigate the effects of SsD on the CYP1A2 and CYP2D6 mRNAs, protein expression, and relative enzyme activities in HepaRG cells. Methods HepaRG cells were cultured with SsD at concentrations of 0.5, 1, 5 and 10 μM for 72 hours. mRNA and protein expression of CYP1A2 and CYP2D6 were analyzed with real-time PCR and Western blot analysis. Relative enzyme activities were analyzed with HPLC based on consumption of the specific probe substrate. Results SsD significantly induced expression of mRNA and increased relative activity of CYP1A2 in HepaRG cells after the cells had been treated with SsD at concentrations of 1, 5 and 10 μM. SsD also induced protein expression of CYP1A2 at concentrations of 5 and 10 μM. SsD exhibited an inductive effect on CYP2D6 mRNA and protein expression, while increasing the relative activity of CYP2D6 at concentrations of 5 and 10 μM. Conclusion This study is the first to investigate the effect of SsD on CYP1A2 and CYP2D6 in HepaRG cells, and the results may provide some useful information on potential drug–drug interactions related to clinical preparations containing SsD or Bupleurum .
研究领域:
药理学
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毒理学
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分子生物学
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中药学
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产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2021
·Vol. 193
·期 7
·2029-2042
·
IF 2.926
Xu Jian-Miao,Cao Hui-Ting,Wang Ming,Ma Bao-Jian,Wang Liu-Yu,Zhang Kai,Cheng Feng,Xue Ya-Ping,Zheng Yu-Guo
d -amino acid oxidase (DAAO) is widely used in the industrial preparation of l -amino acids, and cultivating Escherichia coli ( E. coli ) expressing DAAO for the biosynthesis of l -phosphinothricin ( l -PPT) is very attractive. At present, the biomass production of DAAO by fermentation is still limited in large-scale industrial applications because the expression of DAAO during the fermentation process inhibits the growth of host cells, which limits higher cell density. In this study, the factors that inhibit the growth of bacterial cells during a 5-L fed-batch fermentation process were explored, and the fermentation process was optimized by co-expressing catalase (CAT), by balancing the biomass and the enzyme activity, and by adding exogenous d -alanine ( d -Ala) to relieve the limitation of DAAO on the cells and optimize fermentation. Under optimal conditions, the DO-STAT feeding mode with DO controlled at 30% ± 5% and the addition of 27.5 g/L lactose mixed with 2 g/L d -Ala during induction at 28 °C resulted in the production of 26.03 g dry cell weight (DCW)/L biomass and 390.0 U/g DCW specific activity of DAAO; an increase of 78% and 84%, respectively, compared with the initial fermentation conditions. The fermentation strategy was successfully scale-up to a 5000-L fermenter.
研究领域:
生物技术
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微生物学
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酶学
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工业发酵
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DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
·
2017
·Vol. 50
·期 9
·748-753
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IF 0.629
Zhaoyu Wang,Rongling Yang,Jizhong Wang,Yanhong Bi,Chun Zhu,Xiangjie Zhao,Linghong Nie,Wenqian Li
Regioselective enzymatic glycosylation of D-glucose and various structural alcohols for synthesizing β-D-glucopyranosides was successfully conducted. Among the β-glycosidases from seven potential plant seeds, the low-cost β-glycosidase from Prunus persica seed displayed excellent activity for salidroside preparation. Several crucial parameters, such as the solvent, buffer pH, buffer content, substrate molar ratio, enzyme dosage, and temperature were examined for yield optimization. Under the optimal conditions, the initial reaction rate and yield of salidroside were as high as 3.04 mM/h and 18.90%, respectively. Moreover, the alcohol acceptor recognition of the enzyme in synthesizing β-D-glucopyranosides was also investigated. The experimental data indicated that β-glycosidase activity and yield varied widely among all the tested alcohols due to the specific spatial structures of various acceptors.
研究领域:
生物化学
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酶工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Fang Li,Haili Lin,Huiqin Yu,Xuemei Jia,Shifu Chen,Jing Cao
Replacing the sluggish oxygen evolution reaction with the oxidation of benzyl alcohol to construct the hybrid water electrolysis system has been attractive for its merits of environmentally friendly and economically efficient. However, the activity of the catalyst to oxidize alcohols needs to be further improved. Tailoring the d-band center (E d ) has been proven as an effective method to promote the hydrogen evolution reaction (HER). How feasible is this strategy in the oxidation of benzyl alcohol? Here, using Co 2 C as a research platform, the doping nonmetal heteroatom (P, S, N) engineering is adopted to promote its electrocatalytic BA oxidation and HER performance. The results of electrochemical tests show that the P-doped Co 2 C (P–Co 2 C) only requires a low potential of 1.33 and 1.38 V vs. RHE to achieve current densities of 20 and 100 mA cm −2 for BA oxidation, which is superior to that of S–Co 2 C, N–Co 2 C, and pristine Co 2 C. The conversation and faradaic efficiency for BA is up to 98.1% and 93.8% during ten consecutive cycle tests. The P–Co 2 C also exhibited outstanding activity and stability toward HER. The density functional theory (DFT) calculation revealed that specified P doping could modify the d-band center of Co 2 C approaching the peak of the volcano map (electrochemical overpotentials ∼ E d ). The Gibbs free energy of the BA oxidation was also reduced, thus optimizing the adsorption and desorption process of intermediates. On the other hand, the catalyst surface physical properties of Co 2 C such as hydrophilicity was promoted by the doped heteroatoms which was favorable for the gas-liquid-solid triphase electrocatalytic reaction. This work offers a facial perception of regulating the d-band to design advanced bifunctional electrocatalysts for organic matter oxidation and HER.
研究领域:
电化学
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材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2020
·
IF 2.952
Xuelian Zhou,Yi Shen,Yong Xu,Venkatesh Balan
2-Keto- d -gluconic acid (2-KGA) is a high-value-added product from lignocellulosic straw-based biorefining process obtained via cell catalysis using Gluconobacter oxydans ( G. oxydans ); nonetheless, the economical production has some limitations because of the formation of undesirable mixture products of keto-gluconic acid from glucose. In this study, it was demonstrated that pulse addition of hydrogen peroxide (H 2 O 2 ) to synthetic media was beneficial to improve the conversion rate of glucose to 2-KGA by 1.47-fold in G. oxydans . Moreover, some lignocellulosic degradation compounds served as substitute and played the role of H 2 O 2 on corn stover hydrolysate for the production of 2-KGA. By conducting qRT-PCR analysis, eight dehydrogenase genes were identified in G. oxydans , which were responsible for regulating 2-KGA production. Moreover, most of the identified genes were found to produce membrane-bound glucose dehydrogenase and gluconate 2-dehydrogenase, and were up-regulated by adding H 2 O 2 or degradation compounds. These up-regulated genes could be responsible for directing cell catalysis of glucose to 2-KGA in G. oxydans .
研究领域:
生物化学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2016
·
IF 2.628
Yilong Wang,Yun Zhang,Aijun Sun,Yunfeng Hu
A novel marine microbial esterase PHE14 was cloned from the genome of Pseudomonas oryzihabitans HUP022 isolated from the deep sea of the western Pacific Ocean. Esterase PHE14 exhibited very good tolerance to most organic solvents, surfactants and metal ions tested, thus making it a good esterase candidate for organic synthesis that requires an organic solvent, surfactants or metal ions. Esterase PHE14 was utilized as a biocatalyst in the asymmetric synthesis of D-methyl lactate by enzymatic kinetic resolution. D-methyl lactate is a key chiral chemical. Contrary to some previous reports, the addition of an organic solvent and surfactants in the enzymatic reaction did not have a beneficial effect on the kinetic resolution catalyzed by esterase PHE14. Our study is the first report on the preparation of the enantiomerically enriched product D-methyl lactate by enzymatic kinetic resolution. The desired enantiomerically enriched product D-methyl lactate was obtained with a high enantiomeric excess of 99% and yield of 88.7% after process optimization. The deep sea microbial esterase PHE14 is a green biocatalyst with very good potential in asymmetric synthesis in industry and can replace the traditional organic synthesis that causes pollution to the environment.
研究领域:
生物化学
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工业微生物学
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酶工程
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2022
·
IF 10.508
Yu-Xuan Xiao,Jie Ying,Jiang-Bo Chen,Yuan Dong,Xiong Yang,Ge Tian,Jinsong Wu,Christoph Janiak,Kenneth I. Ozoemena,Xiao-Yu Yang
The heavy d-π effect is an important theoretical model for strong Pt–C interaction, and its enhancement is critical to the high-performance design of Pt/C electrocatalysts. Common chemical N-doping to the carbon support can provide possibilities for enhanced electrocatalysis but most often leads to random interaction with Pt nanoparticles (Pt-NPs) and uncontrollable tuning of the heavy d-π effect. Directional confinement of Pt-NPs within N-doped carbon to directly enhance the heavy d-π effect is therefore mostly preferred but rarely reported. Herein, confined ultrafine Pt-NPs in N-doped porous carbon fibers (Pt@NDPCF) were obtained by a combination method involving electrospinning, carbonization, and directional replacement. Such a synthetic strategy leads to highly dispersed, ultrafine Pt-NPs in hierarchically porous carbon fibers and a strong directional interaction of Pt with pyridinic N, which significantly enhances the heavy d-π effect, greatly facilitating electron transfer and optimizing Pt 5d orbitals. Based on these advances, Pt@NDPCF exhibited outstanding activity and superior durability in the hydrogen evolution reaction (HER), with 24 mV lower overpotential at 10 mA cm–2 and a much smaller activity loss after 10,000 cycles of durability tests in comparison with a commercial Pt/C catalyst. This work sheds new lights on the design of high-performance Pt-based nanomaterials toward HER or other practical applications.
研究领域:
材料科学
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电催化
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2017
·
IF 2.497
Wen Qin,Chengjin Wu,Wei Song,Xiulai Chen,Jia Liu,Qiuling Luo,Liming Liu
In this study, an eco-friendly and high-efficient method for the bioconversion of phosphatidylserine (PS) from phosphatidylcholine (PC) and l -serine was developed. After the strain screening, the Streptomyces chromofuscus phospholipase D ( Sc PLD) was chosen and expressed in Escherichia coli BL21 with pET28a (+). After optimization, the maximal specific productivity and Sc PLD hydrolysis activity reached 9049.6 U/g and 10.6 U/mL, respectively, while induction with 2 g/L lactose, at 25 °C for 12 h. The maximal conversions of PC to PS was 93.4% with a final PS concentration of 106.2 g/L (53.1 g/L/h) under theoptimal conditions: 0.153 M PC in CPME, 2.3 M l-ser in sodium acetate buffer, 2.0 g lyophilized cells/mol PC, 100 mM Ca 2+ , 40 °C, and 2 h of incubation. After scale-up to 1 L, the conversions and yield maintained at 85.4% and 97.2 g/L. Therefore, the enzymatic process showed great potential for industrialization of PS.
研究领域:
生物化学
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酶工程
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工业微生物学
✓ 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）