JOURNAL OF MOLECULAR LIQUIDS
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2024
·
IF 5.3
Xueli Zuo,Qi Hao,Weiyi Su,Jiahui Ding,Jun Liang,Honghai Wang,Chun Yang,Jianxin Chen,Peng Guo,Yanjun Jiang
In the context of the severe global carbon emission crisis, green and sustainable enzymatic reactions are garnering widespread attention in the industry. However, these processes still face numerous challenges, such as limitations imposed by reaction equilibrium, product decomposition, and inhibition. Product removal via crystallization has the potential to address these issues. More importantly, crystal product properties can be directly manipulated during enzymatic reactive crystallization (ERC), such as polymorphic purity, size, and morphology in a single batch. In the synthesis of cefaclor catalyzed by penicillin G acylase (PGA), primary and secondary hydrolysis greatly limited the efficiency of the reaction. Thus, ERC was performed to combine the advantages of green enzymatic reactions and controllable direct crystallization. Initially, a supersaturated solution of the substrate was established, and cefaclor crystals were seeded to the enzymatic reaction system at a proper time. Subsequently, operating parameters were adjusted to facilitate selective crystallization of cefaclor. It is noteworthy that both immobilized and free enzymes were examined in our research. Ultimately, cefaclor crystals with purity exceeding 99% were obtained directly. The yield of cefaclor reached as high as 88%. It is believed that this method held significant promise for the green and efficient production of high-purity cefaclor and demonstrated considerable potential for application in more similar pharmaceutical scenarios.
研究领域:
药物化学
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绿色化学
·
生物催化
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DOI
高影响因子
JOURNAL OF NATURAL PRODUCTS
·
2024
·
IF 3.3
Weihong Wang,Jiaxu Shang,Shupeng Yin,Kunyu Xia,Rui Ma,Weiming Zhu,Peng Fu
Metabolites with high chemical reactivity serve important roles in chemical defenses of organisms. Formaldehyde, as a simple and highly reactive small molecule, can be produced by microorganisms, plants, and animals. Its toxicity is well known, but information about its other biological functions remains scarce. Here, we report that the natural product SEK34b produced by Streptomyces species can react nonenzymatically with formaldehyde in water to yield the methylene-bridged dimer phaeochromycin F. This process can eliminate the toxic substance formaldehyde produced by Staphylococcus aureus. Furthermore, there is a substantial inhibitory impact of phaeochromycin F on S. aureus. We hypothesize that these constitute an integrated system of defense and attack of Streptomyces species against competitors. Our study indicates that formaldehyde can react with vancomycin and tigecycline under mild conditions to generate the derivatives bearing an imidazolidin-4-one moiety, thereby reducing the antibacterial activity of these antibiotics. These data provide a possible chemical interaction mechanism of bacteria involving the nonenzymatic reactions of formaldehyde with highly reactive natural products.
研究领域:
微生物学
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生物化学
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药理学
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DOI
PubMed
高影响因子
Food Bioscience
·
2023
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IF 5.2
Xianghui Kong,Weiqi Xu,Kaixin Zhang,Guijie Chen,Xiaoxiong Zeng
Theaflavins (TFs) and theasinensins (TSs) are the key components formed from the enzymatic oxidation of tea catechins , contributing significantly to the biological activities and taste of black and Oolong teas. In this study, we aimed to reveal the catechin conversion and the enzymatic synthesis of TFs and TSs under reaction temperatures and pH values using polyphenol oxidase (PPO) from potato tuber ( Solanum tuberosum L.). The results indicated that different temperatures, pH values and durations had significant effects on the conversion of catechins and the formation of TFs and TSs. During the reaction, the most of catechin substrates was consumed at 60–90 min after reaction initiation, and large amounts of the products TFs (0.04–0.41 mg/mL) and TSs (0.51–1.52 mg/mL) were obtained. The content of TSs was significantly higher and the maximum content of TSs was more than three times that of TFs. Reaction at a lower temperature (20 °C) is suitable for producing dimers, especially for TFs. Higher pH value resulted in higher catechin consumption and higher TSs content, while the maximum of TFs was obtained at pH 5.0. The present results provided a theoretical basis and practical guidance for the targeted processing of tea catechin dimers in vitro .
研究领域:
食品科学
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生物化学
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产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 18
·9893-9898
·
IF 3.049
Qingju Liu,Ping Han,Hui Wang,Wenwen Gong,Xiaoyuan Feng
Currently known rapid determination of fungicides usually relies on antibody-based immunoassay. This paper reports a simple antibody-free colorimetric assay for chlorothalonil via the inhibition of an enzyme-triggered reaction. The enzymatic activity of glyceraldehyde-3-phosphate dehydrogenase was significantly inhibited by chlorothalonil, and the color change of NBT-PMS system induced from NADH formation was suppressed, which could be used indirectly to assay chlorothalonil. The limit of detection (LOD) was 0.05 μM with a linear range from 0.5 to 10 μM, and the detection of 1 μM chlorothalonil in solution was achieved with a naked-eye readout. In addition, the colorimetric measurement results of the cucumber samples showed a good recovery rate, although the sensitivity was less effective than the instrumental method. Nevertheless, the results demonstrates that the chlorometric method provides potential opportunities for reliable, cost-effective quantitative detection for chlorothalonil residues in vegetables.
研究领域:
食品科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Jun Xiao,Juan Huang,Ying Wang,Xiuwen Qian
Although constructed wetland (CW) technology is widely used to eliminate emerging organic pollutants, the removal pathway of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in CW system have not been fully understood yet. This study aims to deeply probe into the fate and behavior of perfluorooctanoic acid (PFOA) in CW system. Findings indicated that the removal efficiency of PFOA by CW system was 49.69–73.63 % with initial concentrations at 100–1000 μg/L. Substrate was the main “sink” of PFOA into the CWs (46.22–50.83 %), and the plant uptake (1.99–2.48 %) accounted for a small proportion. Transformation products in the effluent of CW systems included a series of short-chain perfluorinated carboxylic acids (PFCAs), hydrogen-containing perfluoroalkanes and other organic fluorides. Activated pathways of xenobiotics biodegradation suggested that enzyme-mediated biochemical reactions might be responsible for the PFOA transformation. The transformation pathway included enzymatic decarboxylation , hydroxylation, hydrolysis, dehydrogenation and dehalogenation, as well as non-enzymatic reactions. These discoveries provide new insights into the in-depth understanding environmental behavior of PFOA in ecosystem and lay the foundation for further ecological remediation.
研究领域:
环境科学
·
生态学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
·
IF 5.518
Mengqian Shi,Na Li,Ruirui Xing,Tifeng Jiao
Fluorescent dye labeled peptides and oligonucleotides are important tools for biochemical and cellular research. Dityrosine bond is easily formed in vitro and shows blue fluorescence, so it can be used as a useful symbol of oxidation conditions in biological systems. The formation of dityrosine can be carried out by enzymatic reaction , Fenton reaction and photoinitiation reaction. The enzymatic reaction has attracted much attention because of its mild reaction conditions, which can be performed at room temperature and pressure, and the reaction rates are faster than the corresponding non-catalytic reaction. In this study, peroxidase is selected to catalyze the dipeptides containing tyrosine, resulting nanostructures containing dipeptides with stable blue fluorescence under mild conditions. Nanostructured peptides with stable fluorescence can be applied to fluorescent labeling, and the reaction catalyzed by enzymes to produce blue fluorescence can be used as candidates for lighting inflammatory cells and designing visual materials.
研究领域:
生物化学
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细胞生物学
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材料科学
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产品关联
DOI
高影响因子
Analytical Methods
·
2021
·Vol. 13
·期 37
·4228-4237
·
IF 2.896
Jing Chen,Yali Xu,Fanghong Xu,Qian Zhang,Shuying Li,Xiaoquan Lu
Amino-functionalized two-dimensional (2D) MOFs have great potential in biosensors due to their excellent water solubility, high fluorescence, large specific surface area, good adsorption properties and good ability to enrich the target analytes. Fluorescence detection of hydrogen peroxide and glucose mostly relies on monitoring the single fluorescence intensity changes in a single excitation wavelength. Here, a ratiometric fluorescence sensor based on NH2-MIL-53(Al) nanosheets to sensitively detect H2O2 and glucose through enzymatic reactions was developed. o-Phenylenediamine (OPD) was oxidized by H2O2 in the presence of horseradish peroxidase (HRP). Then, the oxidation product could be self-assembled on NH2-MIL-53(Al) nanosheets by hydrogen bonding and π–π stacking. The orbital interaction or the fluorescence resonance energy transfer (FRET) between the nanosheets and the oxidation product could effectively quench the fluorescence of the nanosheets at 433 nm. At the same time, the oxidation product provided a new emission peak at 564 nm. The fluorescence ratio signal changes generated by this oxidation process were used to stably and sensitively detect H2O2 and glucose. Structural and mechanistic analysis was carried out by calculation methods such as AICD and ORCA to explore the π electron structure characteristics, the hole/electron orbitals and the quenching phenomenon. The detection limit was 26.9 nM for H2O2 and 0.041 μM for glucose. The detection of glucose in human serum has a satisfactory recovery of 97.4–102.8%. It is clear that the sensor has a good application prospect in real sample analysis.
研究领域:
生物传感
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分析化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Sizhe Zhang,Qi Pu,Xinyi Deng,Lu Zhang,Nengsheng Ye,Yuhong Xiang
Choline (ChO) is a biomarker of many diseases. Its accurate and sensitive detection is of great significance for the diseases diagnosis. Gold nanoclusters with bovine serum albumin as template (BSA-AuNCs) were synthesized by microwave-assisted method. A ratiometric fluorescence sensor was constructed based on BSA-AuNCs and 2,3-diaminophenazine, which was the oxidation product of o-phenylenediamine. Combined with cascade enzymatic reaction, it was used for the detection of choline. In the detection system, choline oxidase improved the selectivity of detection, and the peroxidase-like activity of molybdenum disulfide nanosheets shortened the detection time. The linear ranges of choline detection by ratiometric fluorescence sensor were 0.5–20 μM and 20–100 μM. The detection limit was 0.27 μM. The ratiometric fluorescence sensor was easy to operate and had good selectivity. Compared with single signal sensor, it can effectively reduce the error interference such as environmental change, and the detection result was more accurate.
研究领域:
分析化学
·
生物医学
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产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 2
·027523
·
IF 3.721
Gangbing Zhu,Depeng Zhang,Yuzhi Ma,Yinhui Yi
Chiral recognition is facing serious challenges in achieving quantitative determination for a definite isomer in a complex sample. Herein, by introducing respectively β-D-glucose oxidase (β-D-GOD) and glucose (Glu) enantiomers (D-, L-Glu) as a model enzyme and analytes as well as carbon nanotubes (CNTs) to immobilize β-D-GOD and accelerate electron transfer processes, an electrochemical chiral sensing platform on the basic of the specific enzymatic reactions was proposed for the first time in chiral recognition. Owing to the high specificity of enzyme, many enzymes can catalyze selectively one enantiomer reaction but have little ability to catalyze the other enantiomers and interferents, resulting that the chiral sensors based on the specific enzymatic reactions have high selectivity and can be used for the direct and selective detection of enantiomer in the complex samples. It's believed the proposed electrochemical chiral recognition strategy based on specific enzymatic reactions will have important application values for direct determination of enantiomer in real samples.
研究领域:
分析化学
·
生物化学
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DOI
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2019
·
IF 2.739
Wenjia Li,Dong Liu,Xiaoya Bi,Tianyan You
Herein a novel ratiometric fluorescence strategy based on enzyme-triggered inner filter effect (IFE) was described to sensitively detect mercury ions (Hg 2+ ) for the first time by using l -proline-protected gold nanoclusters (AuNCs) and 2,3-diaminophenazine (DAP) as IFE fluorophore and absorber. The IFE was derived from the overlap between the emission band of AuNCs and absorption band of DAP and confirmed by fluorescence lifetime decay tests. Based on IFE principle and ratiometric strategy, laccase (LACC)-catalyzed o-phenylenediamine (OPD) oxidation was utilized to produce DAP, whereas the activity of LACC can be monitored by Hg 2+ . In this way, the existence of Hg 2+ could depress the emission of DAP while restore that of AuNCs , achieving the dual signal response of Hg 2+ , and their emission intensity ratio was dependent on the concentration of Hg 2+ . Under the optimized detection conditions, the linear range for Hg 2+ determination was from 0.8 to 35 μM with a detection limit of 0.27 μM. Besides, it was successfully applied to the analysis of tap water and Yangtze river water. Our strategy can be used to assess the activity of LACC, and it also provided a novel way to construct other enzyme-based biosensors.
研究领域:
分析化学
·
环境科学
·
生物传感
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DOI
高影响因子
CLAYS AND CLAY MINERALS
·
2024
·Vol. 71
·期 6
·745-759
·
IF 2
Peiping Zhang,Tongtong Liu,Xue Sun,Qing Liang,Wei Zhang,Weikun Ning,Wenqing Li,Xuefa Shi,Shiding Miao
Natural clays are often employed as substrates for heterogeneous catalysts. However, the direct use of raw clays as catalysts has received less research attention. The objective of the present study was to help fill this gap by investigating catalytic properties of raw pelagic clays (PC) collected from the Indian Ocean. The raw PC were discovered to be efficient catalysts in the reduction of 4-nitrophenol (4-NP) in the presence of NaBH4. The effects of parameters including pH values, dosages of PC, and initial concentration of 4-NP and NaBH4 on the conversion or degradation rate of 4-NP have been investigated. The 4-NP was observed to be completely degraded within 480 s under conditions of 0.10 mM 4-NP, 25.0 mM NaBH4, and 0.20 g/L PC at an initial pH value of 7.0. The apparent rate constant was evaluated to be 27.53 × 10–3 s–1. Unlike previous pseudo-first order kinetics experiments, the induction period and degradation stages were observed to occur simultaneously during the PC catalysis. The S-shaped kinetics for 4-NP conversion was found to be perfectly matched by Fermi's function, and the enzyme-like catalysis by PC was appointed to describe the kinetics. Species of Fe(III), Mn(IV), and Mn(III) in PC were found to be essential, and were partly reduced to Fe(0) and Mn(II) by NaBH4 in our reaction, contributing to rapid conversion of 4-NP to 4-aminophenol (4-AP). The raw PC was converted to magnetic PC (m-PC) particles, which made PC particles separate easily for cycling use. This discovery would also have applications in continuous flow-fluid catalysis.
研究领域:
环境科学
·
催化化学
·
材料科学
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产品关联
DOI
高影响因子
Toxins
·
2014
·Vol. 6
·期 11
·3157-3172
·
IF 2.48
Wei Zhang,Beibei Xue,Mengmeng Li,Yang Mu,Zhihui Chen,Jianping Li,Anshan Shan
Aflatoxin B1, a type of highly toxic mycotoxin produced by some species belonging to theAspergillusgenus, such asAspergillus flavusandAspergillus parasiticus, is widely distributed in feed matrices. Here, coumarin was used as the sole carbon source to screen microorganism strains that were isolated from types of feed ingredients. Only one isolate (ND-1) was able to degrade aflatoxin B1after screening. ND-1 isolate, identified as a strain ofAspergillus nigerusing phylogenetic analysis on the basis of 18S rDNA, could remove 26.3% of aflatoxin B1after 48 h of fermentation in nutrient broth (NB). Optimization of fermentation conditions for aflatoxin B1degradation by selectedAspergillus nigerwas also performed. These results showed that 58.2% of aflatoxin B1was degraded after 24 h of culture under the optimal fermentation conditions. The aflatoxin B1degradation activity ofAspergillus nigersupernatant was significantly stronger than cells and cell extracts. Furthermore, effects of temperature, heat treatment, pH, and metal ions on aflatoxin B1degradation by the supernatant were examined. Results indicated that aflatoxin B1degradation ofAspergillus nigeris enzymatic and this process occurs in the extracellular environment.Keywords:Aspergillus niger;coumarin;aflatoxin B1;degradation
研究领域:
微生物学
·
毒理学
·
食品科学
✓ 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）