CATALYSIS TODAY
·
2014
·
IF 3.309
Senlin Wang,Wei Wei,Yu Zhao,Hexing Li,Hui Li
In this paper, highly ordered mesoporous silica nanospheres externally covered by methyl groups ( CH 3 ) but internally grafted by aminopropyl groups ( NH 2 ) were used as host matrix for loading Ru–B amorphous alloy nanoparticles (NPs). The NH 2 and the CH 3 groups served synergistically as effective functionalities for highly dispersing Ru–B NPs within the pore channels of the mesoporous host. Such catalyst was used in the liquid-phase d -glucose hydrogenation and delivered much higher activity than industrial Raney Ni and the commercial Ru/C catalysts. Meanwhile, it could be used repetitively for more than 9 times, showing a good potential in practical applications. This work demonstrated that the surface properties of mesoporous materials can be modified through region-selective immobilization of diverse organic groups, which is essential to optimize the catalysis for some reactions.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2023
·
IF 3.4
Shuangshuang Duan,Yonghua Chen,Guodong Wang,Zebin Li,Shitong Dong,Yingshuai Wu,Yuanwei Wang,Chunling Ma,Ruiming Wang
D -Allose is a rare cis-caprose with a wide range of physiological functions, which has a wide range of applications in medicine, food, and other industries. L -Rhamnose isomerase ( L -Rhi) is the earliest enzyme found to catalyze the production of D -allose from D -psicose. This catalyst has a high conversion rate, but its specificity for substrates is limited; thus, it cannot fulfill the requirements of industrial production of D -allose. In this study, L -Rhi derived from Bacillus subtilis was employed as the research subject, and D -psicose as the conversion substrate. Two mutant libraries were constructed through alanine scanning, saturation mutation, and rational design based on the analysis of the secondary structure , tertiary structure , and interactions with ligands of the enzyme. The yield of D -allose produced by these mutants was assessed; it was found that the conversion rate of mutant D325M to D -allose was increased by 55.73 %, and the D325S improved by 15.34 %, while mutant W184H increased by 10.37 % at 55 °C, respectively. According to modeling analysis, manganese (Mn 2+ ) had no significant effect on the production of D -psicose from D -psicose by L -Rhi. The results of molecular dynamics simulation demonstrated that the mutants W184H, D325M, and D325S had more stable protein structures while binding with the substrate D -psicose, as evidenced by its root mean square deviation (RMSD), root mean square fluctuation (RMSF), and binding free energy values. It was more conducive to binding D -psicose and facilitating its conversion to D -allose, providing the basis for the production of D -allose.
研究领域:
生物化学
·
酶学
·
生物技术
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结构生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Theranostics
·
2018
·
IF 8.537
Zhenyuan Bian,Jin Yan,Simeng Wang,Yijie Li,Yi Guo,Bohan Ma,Hao Guo,Zhijie Lei,Chun Yin,Yi Zhou,Min Liu,Kaishan Tao,Peng Hou,Wangxiao He
Peptides are a rapidly growing class of therapeutics with many advantages over conventional small molecule drugs. Dextrorotary (D)-peptides, with increased enzymatic stability and prolonged plasma half-life in comparison with natural L-peptides, are considered to have great potential as recognition molecules and therapeutic agents. However, the in vivo efficacy of current therapeutic D-peptides is hindered by their inefficient cellular uptake in diseased tissues. Methods: To overcome physiological and cellular barriers to D-peptides, we designed a gold-based ultra-small nanocarrier coupled with polylysine (PLL) and a receptor-targeted peptide to deliver therapeutic D-peptides. Using a D-peptide p53 activator (DPA) as a proof of concept, we synthesized, functionalized and characterized gold- and DPA-based nanoparticles termed AuNP-DPA. Results: AuNP-DPA were effectively enriched in tumor sites and subsequently internalized by cancer cells, thereby suppressing tumor growth via reactivating p53 signaling. More importantly, through a series of in vivo experiments, AuNP-DPA showed excellent biosafety without the common side effects that hinder p53 therapies in clinic trials. Conclusion: The present study not only sheds light on the development of AuNP-DPA as a novel class of antitumor agents for drugging the p53 pathway in vivo, but also supplies a new strategy to use D-peptides as intracellular PPI inhibitors for cancer-targeted therapy.
研究领域:
生物医学
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纳米医学
·
癌症研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2022
·Vol. 14
·期 12
·2317
·
IF 4.967
Juliene Oliveira Campos de França,Deborah da Silva Valadares,Mateus Freitas Paiva,Sílvia Cláudia Loureiro Dias,José Alves Dias
Poly(lactic acid) (PLA) is an important polymer that is based on renewable biomass resources. Because of environmental issues, more renewable sources for polymers synthesis have been sought for industrial purposes. In this sense, cheaper monomers should be used to facilitate better utilization of less valuable chemicals and therefore granting more sustainable processes. Some points are raised about the need to study the total degradability of any PLA, which may require specific composting conditions (e.g., temperature, type of microorganism, adequate humidity and aerobic environment). Polymerization processes to produce PLA are presented with an emphasis on D,L-lactic acid (or rac-lactide) as the reactant monomer. The syntheses involving homogeneous and heterogeneous catalytic processes to produce poly(D,L-Lactic acid) (PDLLA) are also addressed. Additionally, the production of blends, copolymers, and composites with PDLLA are also presented exemplifying different preparation methods. Some general applications of these materials mostly dedicated to the biomedical area over the last 10–15 years will be pointed out.Keywords:poly(lactic acid)-PLA;polymerization based on D,L-lactic acid;D,L-lactide;stereo polymerization of D,L-lactic acid;blends of PLA;poly(DL-lactide-co-polymer);composites of PDLLA
研究领域:
高分子化学
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生物材料学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Yibin Yang,Di Gao,Yingqing Ou,Yang Yang,Peng Xiao,Yunhuai Zhang
Currently, developing highly active and low-cost electrocatalytic materials for oxygen evolution reaction (OER) is an enormously grand challenge. Herein, we developed a novel and highly active Mn doped Co 2 Fe layer double hydroxide (LDH) electrocatalyst for OER. We discovered that these electrocatalytic materials can be directly grown on carbon papers to construct high-specific-surface-area electrode, which shows the lowest overpotential of 266 mV at 10 mA cm −2 . Furthermore, after introducing Mn element, DFT + U calculation found that the ∗OOH of Fe-site on Co 2 Fe 0.67 Mn 0.33 LDH could draw more electrons than Co 2 Fe LDH due to the electronegativity differences between Fe-site on Co 2 Fe 0.67 Mn 0.33 LDH and Fe-site on Co 2 Fe LDH, which is reason that the energy level of Fe 3d (e g ) was obviously downshifted by d-d repulsion of Mn 3d and Fe 3d in the neighboring sites of Co 2 Fe 0.67 Mn 0.33 LDH after doped Mn element, which leads to reduce charge-transfer energy from O 2p to Fe 3d (e g ) to promote oxygen evolution processes for OER. Meanwhile, the band gap is also decreased after doped Mn element in Co 2 Fe LDH due to the downshifted e g orbital energy of Fe 3d. This study gives a general avenue to design and developing efficiently active LDH electrocatalysts for OER in the future.
研究领域:
材料科学
·
电化学
·
催化
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2021
·
IF 5.279
Zhaohui Guo,Christian M. Pedersen,Pengfei Wang,Minjun Ma,Yingqing Zhao,Yan Qiao,Yingxiong Wang
The isomerization of d-glucose to d-fructose plays a key role in the biochemical and chemical conversion of biomass, and it is therefore desirable to develop and improve catalysts for this reaction. In this study, the environmentally friendly polymer poly(amidoamine) (PAMAM) dendrimer’s properties as catalysts for this isomerization are investigated. The experimental results showed that the PAMAM dendrimers, which have basic terminal groups, can effectively promote the d-glucose isomerization reaction. Under the optimized reaction conditions, d-fructose was generated with a 20% maximum yield and above 90% selectivity. 13C and 2H isotope experiments by NMR were carried out to explore the reaction mechanism. When the reaction was performed in D2O, the C1 signal of d-fructose changed to a triplet, which confirmed that the C1 carbon binds to a deuterium atom, i.e., isotopic exchange. It was also found that the deuterium atom at the C2 position of d-glucose-2-d1 cannot transfer to d-fructose. These data indicate that PAMAM dendrimers catalyze d-glucose isomerization through a mechanism, which includes deprotonation, formation of ene-diol intermediate, and proton exchange with the solvent.
研究领域:
生物化学
·
绿色化学
✓ 已验证
DOI
高影响因子
PHYTOMEDICINE
·
2025
·
IF 8.3
Guifang Fan,Xiaojiaoyang Li,Fanghong Li,Ranyun Chen,Xiaoyong Xue,Le Wang,Qi Zheng,Shuni Duan,Ranyi Luo,Rong Sun,Runping Liu
Background : Radix Bupleuri (RB) and acetaminophen (APAP) are two popular medications having potential hepatotoxicity and substantial risks of irrational co-administration and excessive use, posing an overlooked danger of drug-induced liver injury (DILI). Autophagy is a protective mechanism against APAP-induced DILI, yet, saikosaponin d (SSd) in RB has been characterized to regulate autophagy, although the current findings are controversial. Purpose : We aim to elucidate whether SSd promoted APAP-induced liver injury by regulating autophagy. Methods : UPLC-MS analysis was employed to measure the hepatic abundance of APAP-cysteine protein adducts. Multiple techniques such as fluorescence probe, proteinase K protection assay, immunoprecipitation-coupled proteomic analysis, surface plasmon resonance, molecular docking and et.al were applied to evaluate the SSd on autophagy flux. Results : We discovered that, by inhibiting autophagy, SSd impaired the removal of APAP-cysteine protein adducts and delayed the compensation of damaged mitochondria. This ultimately potentiated the development of severe liver toxicity induced by subtoxic APAP. The use of autophagy probes, transmission electron microscopy, membrane curative assay, and protein K assay collectively revealed that SSd predominately disrupted autophagosome-lysosome fusion, without affecting other stages of autophagic flux. Immunoprecipitation-coupled proteomic analysis and surface plasmon resonance further found that SSd directly bound to GABARAP, thus preventing the recruitment and autoactivation of STX17 and the following assembly of STX17-SNAP29-VAMP8 complex. Conclusion : In conclusion, our findings not only highlight the significant risk of drug-induced liver injury associated with the co-administration of RB and APAP in clinical practice but also unveils that GABARAP-SNARE complex is a novel druggable target for the treatment of autophagy-related diseases.
研究领域:
药理学
·
肝脏病学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2024
·
IF 5.6
Xiupei Yang,Xiaoyi Xie,Ling Jiang,Yuxiu Fan,Chenglin Zhang,Ya Wang
Most conventional nanozymes have poor specificity and low activity, and designing high-performance nanozymes remains a challenge. In contrast, single-atom nanozymes have high atom utilization and high reactivity. Here, we prepared Cu single-atom nanozymes (Cu-NC) with excellent peroxidase-like activity by high-temperature pyrolysis using Cu as a transition metal source. The introduction of Cu formed the Cu-N x active site, which accelerated charge transfer between the reactants and the active site and was the key for improving the activity. With Cu-NC as a catalyst, H 2 O 2 rapidly oxidized 3,3′,5,5′-tetramethylbenzidine (TMB) to oxTMB, and the solution turned blue with strong absorption at 652 nm. Because d -penicillamine (D-PA) can reduce oxTMB or react with reactive oxygen species radicals to inhibit the color reaction, we built a colorimetric sensing platform around Cu-NC for the determination of D-PA and successfully used it for the determination of D-PA in urine samples. This work provides new ideas for the design of high-performance nanozymes and the detection of D-PA in real environments.
研究领域:
生物化学
·
医学诊断
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Food Science & Technology
·
2021
·
IF 0
Xiaoyan Chen,Fan Wang,Shijie Liu,Qiang Yu,Wen Wang,Yu Zhang,Zhongming Wang,Zhenhong Yuan
The synthesis efficiency of d-allulose, an ideal sugar substitute and dietary supplement, from d-glucose with whole-cell catalysts was improved by three out of the four tested deep eutectic solvents (DESs) based on choline chloride (ChCl). The promotion effects on the product yields with increments of up to 2.6-fold were observed in reactions with the presence of DESs in the order ChCl/glycerol < ChCl/urea < ChCl/ethylene glycol. DES compositions displayed distinct influences, but all positive effects appeared in the reactions with low DES contents (1–10%). Higher DES contents produced negative effects, and 40% even totally suppressed the reaction. The enhancement of efflux of intracellular molecules was proved by an analysis of the nucleic acid and protein contents in the medium. DES assisted in the increase in cell membrane permeability rather than in the damage of cell wall integrity, accelerating quick contacts between the enzyme and substrate and improving the conversion rate.
研究领域:
化学工程
·
生物化学
·
食品科学
✓ 已验证
DOI
Frontiers in Chemistry
·
2020
·
IF 3.693
Wang Yang,Ravikumar Yuvaraj,Zhang Guoyan,Yun Junhua,Zhang Yufei,Parvez Amreesh,Qi Xianghui,Sun Wenjing
D-allulose, which is one of the important rare sugars, has gained significant attention in the food and pharmaceutical industries as a potential alternative to sucrose and fructose. Enzymes belonging to the D-tagatose 3-epimerase (DTEase) family can reversibly catalyze the epimerization of D-fructose at the C3 position and convert it into D-allulose by a good number of naturally occurring microorganisms. However, microbial synthesis of D-allulose is still at its immature stage in the industrial arena, mostly due to the preference of slightly acidic conditions for Izumoring reactions. Discovery of novel DTEase that works at acidic conditions is highly preferred for industrial applications. In this study, a novel DTEase, DTE-CM, capable of catalyzing D-fructose into D-allulose was applications. In this study, a novel DTEase, DTE-CM, capable of catalyzing D-fructose into D-allulose was DTE-CM on D-fructose was found to be remarkably influenced and modulated by the type of metal ions (co-factors). The DTE-CM on D-fructose was found to be remarkably influenced and modulated by the type of metal ions (co-factors). The 50°C from 0.5 to 3.5 h at a concentration of 0.1 mM. The enzyme exhibited its maximum catalytic activity on D-fructose at pH 6.0 and 50°C from 0.5 to 3.5 h at a concentration of 0.1 mM. The enzyme exhibited its maximum catalytic activity on -fructose at pH 6.0 and 50°C with a Kcat/Km value of 45 mM−1min−1. The 500 g/L D-fructose, which corresponded to 30% conversion rate. With these interesting catalytic properties, this enzyme could be a promising candidate for industrial biocatalytic applications.
研究领域:
食品科学
·
生物化学
·
酶学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
FOOD AND CHEMICAL TOXICOLOGY
·
2018
·
IF 3.977
Ying Xiao,Jialin Dong,Zhiting Yin,Qiguo Wu,Yiming Zhou,Xiaoli Zhou
To elucidate the possible mechanisms for the preventive effect of procyanidin B2 on aging, a combined analysis of metabolic profile and gut microbiome was carried out in the present study. The mimetic aged mice induced by d -galactose injection (500 mg/kg, sc daily), and the preventive group was fed with the diet plus 0.2% procyanidin B2. After 7 weeks of treatment, the spatial memory was assayed using the Morris water maze test. Procyanidin B2 significantly ameliorated the impaired memory and antioxidant abilities induced by d -galactose. Furthermore, metabolomics analysis of plasma based on LC/Q-TOF-MS demonstrated that phosphatidyl cholines , oleic acid , linoleic acid , carnitine , pantothenic acid , and taurocholic acid were significantly increased in the mice treated with procyanidin B2, and pyruvic acid , hydroxybutyric acid , hippuric acid , and cholic acid were decreased significantly. Together, gut microbiome analysis using Illumina sequencing showed that there were significant differences in the Firmicutes / Bacteroidetes ratio and abundance of Roseburia , Lachnospiraceae , and Bifidobacterium between the aging and supplemental procyanidin B2 groups. In summary, procyanidin B2 possessed potential prevention of the cognitive and oxidative impairment via the metabolic pathway regulation related to citrate cycle, fatty acid, and bile acid in the aged mice, accompanied by remodeling the gut flora.
研究领域:
生物化学
·
分子生物学
·
老年医学
·
营养学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2017
·
IF 4.164
Lihong Qiao,Tingting Sun,Xiaohua Zheng,Min Zheng,Zhigang Xie
Targeting imaging to the desired site of action can increase the accuracy and effectiveness of diagnostic and treatment. In this work, a series of fluorescent carbon dots (CDs) were prepared by varying molar ratios of d -glucose (Glu) to l -aspartic acid (Asp). Their photophysical properties, morphologies and structures were investigated in detail. More important, the targeting ability was screened by confocal laser scanning microscopy and flow cytometry. The results indicate that CDs prepared from the optimal molar ratio of Glu/Asp (7:3) exhibit the highest targeting ability on C6 glioma cells. This work highlights the interplay of molecular design and corresponding functions, and open new possibility of developing state-of-art nanoparticles for biomedical applications.
研究领域:
生物医学
·
纳米材料
·
肿瘤学
✓ 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）