CHEMICAL PAPERS
·
2019
·Vol. 74
·期 6
·1831-1838
·
IF 1.246
Cai Zhifeng,Zhang Caifeng,Jia Kang
A fast, simple, green and low-cost synthesis method in aqueous solution was successfully established for the preparation of l -tyrosine protected Cu nanoclusters (Cu NCs). Subsequently, the as-prepared Cu NCs was characterized by UV–vis absorption spectroscopy, fluorescence spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It exhibited good water solubility, excellent photostability and high stability toward high concentration of sodium chloride. The Cu NCs revealed maximum excitation and emission peaks at 430 and 477 nm, respectively. Importantly, the Cu NCs showed a rapid response, a liner relation over the pH ranges from 5.02 to 11.92 and could be repeated for five consecutive cycles without fluorescence decay. Further, the as-prepared Cu NCs was applied for the determination of pH value in water samples. Simultaneously, all above features showed that l -tyrosine protected Cu NCs had great potential for sensing of pH in biological field.
研究领域:
生物化学
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材料科学
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分析化学
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产品关联
DOI
高影响因子
AQUACULTURE
·
2024
·
IF 3.9
Kunyin Jiang,Hong Yu,Lingfeng Kong,Shikai Liu,Shaojun Du,Qi Li
The visually appealing shell colours and intricate patterns of shellfish not only attract consumers but also enhance their economic value. Understanding the inheritance pattern of shell colour and the molecular mechanism of pigmentation is highly important for enhancing breeding efficiency. This study involved the identification of a tyrosine hydroxylase gene ( CgTH ) and the investigation of its function in the metabolism of tyrosine and pigmentation in Pacific oysters. CgTH contains a conserved Biopterin_H domain that consists of a binding site for iron atoms and a binding site for tetrahydrobiopterin (BH4). Quantitative PCR (qPCR) and immunofluorescence analysis revealed that the expression of CgTH was higher in the mantle of black shell oysters in comparison to the white strain. The in vitro and in vivo experiments confirmed that Cg TH is involved in tyrosine metabolism through the catalysis of the conversion of L-tyrosine to L-DOPA. In order to examine its functions in melanin synthesis in oysters, 3-Iodo-L-tyrosine (3-IT) treatment, RNA interference (RNAi), and L-DOPA treatment assays were conducted. The results of our study showed that 3-IT effectively inhibited Cg TH activity, leading to a suppression of tyrosine metabolism. Knockdown of Cg TH hindered the cAMP-CREM-MITF axis and decreased pigmentation. On the other hand, L-DOPA stimulated melanin production through cAMP signaling and counteracted the inhibitory effects of 3-IT on the metabolism of tyrosine. These data indicated that there may be a feedback loop involving Cg TH and the cAMP-CREM-MITF axis that regulates tyrosine metabolism and melanogenesis in Pacific oysters. This study enhances our understanding of the molecular mechanism that governs oyster pigmentation and offers a possible molecular indicator for the targeted breeding of particular strains of Pacific oysters ( Crassostrea gigas ).
研究领域:
海洋生物学
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分子生物学
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遗传学
·
水产养殖
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DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2023
·Vol. 27
·期 3
·753-761
·
IF 2.5
Chu Youqun,Zhang Huixuan,Zhou Huihui,Xu Tengfei,Yan Hui,Huang Zhangkao,Zhao Fengming
The nano-Ag–TiO 2 hollow microsphere precursors were prepared by the one-pot solvothermal method using L-tyrosine as the template agent and reducing agent. Subsequently, the nano-Ag–TiN hollow microsphere composites were formed by reducing nitride in an ammonia-filled atmosphere. The esterification of ethanol solvent and L-tyrosine microdroplet template generates traces of water in situ for the hydrolysis of alkane titanium. As the L-tyrosine microdroplet templates are sacrificed and incorporated into the titanium dioxide matrix, a hybridized hollow structure is formed. With the help of L-tyrosine, the surface of Ag–TiO 2 hollow microsphere precursors appeared folded rough surface, and the nanosilver was mostly distributed in the TiO 2 spherical shell. The constructed Ag–TiO 2 hollow microsphere demonstrated a good linear relationship between the current response value and the concentration in the range of 0.2–220 μM of H 2 O 2 , with the lowest detection limit of 0.04 μM. In the same concentration range, whereas the lowest detection limit of Ag–TiN hollow microsphere was 0.02 μM. The detection results of H 2 O 2 revealed that the Ag–TiN/HMS electrode has outstanding interference resistance, stability, and repeatability.
研究领域:
材料科学
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电化学分析
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生物传感
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产品关联
DOI
高影响因子
TALANTA
·
2019
·
IF 4.916
Xiaoguang Ying,Xiaomei Zhu,Anshun Kang,Xiao Li
In this work, molecularly imprinted electrospun chromogenic membrane(MIP-ECM) was synthesized using P -Hydroxybenzene propanoic acid as imitate template molecule and Poly (vinyl alcohol)(PVA) as substrate. Ninhydrin is used as chromogenic agent for visualizing detection of target molecule l -tyrosine(Tyr). The results showed that molecularly imprinted membrane exhibited selectivity and specific adsorption capacity for l -tyrosine. The influences of environmental factors, such as reaction temperature, the amount of ninhydrin and elution time, on chromogenic properties were examined by SEM and optical microscope. Gray value analysis is proceeded by software Image J. Due to the facilitate preparation and intuitive visualization, the proposed method was a promising candidate for selective recognition of bio-generated acid and amino molecules.
研究领域:
生物化学
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材料科学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOORGANIC CHEMISTRY
·
2025
·
IF 4.7
Wen-Kai Liu,Xiu-Xin Ren,Lian Xu,Juan Lin
Hydroxytyrosol, a naturally occurring chemical with antioxidant and antiviral properties, is widely employed in the nutrition, pharmaceutical, and cosmetic industries. In the present study, a modularized cascade composed of Modules 1 and 2 was designed and implemented to convert l -tyrosine to hydroxytyrosol. Module 1 was a four-enzymatic cascade for converting l -tyrosine to tyrosol. Engineering Module 1 by fine-tuning the expression of the desired enzymes resulted in a robust whole-cell catalyst, BL21 (M1-13), which converted l -tyrosine to tyrosol at high substrate loading. Module 2 involved a 4-hydroxyphenylacetate 3-monooxygenase (HpaBC)-catalyzed reaction to hydroxylate tyrosol to form hydroxytyrosol. The rational design of the HpaB subunit led to a positive variant, HpaB-Mu (T292S/R474A), which was subsequently applied to Module 2 for tyrosol hydroxylation, yielding a robust whole-cell catalyst, BL21 (M2-05). The two designed modules were merged for one-pot conversion of l -tyrosine to hydroxytyrosol by adjusting the ratio and total amount of whole-cell catalyst loading, capable of converting 40 mM of l -tyrosine to 35.8 mM of hydroxytyrosol with a high space–time yield (1.38 g/L/h). The current study proved that engineering HpaB at the substrate tunnel was a feasible way to boost its activity and proposed an effective method for synthesizing hydroxytyrosol from low-cost substrates, which has great economic potential.
研究领域:
生物化学
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合成生物学
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酶工程
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产品关联
DOI
PubMed
高影响因子
POLYMER TESTING
·
2020
·
IF 3.275
Tao Zhou,Hang Xiao,Weifeng Peng,Bo Liang,Yao Liu,Jiangbo Lv,Jianghuai Hu,Ke Zeng,Gang Yang
The pyrolysis behaviors of l -tyrosine-based phthalonitrile(TPN) resin were investigated by thermogravimetric-Fourier transform infrared spectrometry-mass spectrometry (TG-FTIR-MS) and Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The small molecules produced during pyrolysis process of TPN resin were tracked in real time by TG-FTIR-MS. The larger molecules ( m / z > 40) from fast pyrolysis at 900 °C of the TPN resin using Py-GC/MS were identified. From TG-FTIR-MS and Py-GC/MS results, the production pathways of pyrolysis products such as CO 2 , CO, NH 3 , benzonitrile and phenol were analyzed. The possible pyrolysis mechanism of TPN resin under non-oxidizing gaseous environment was proposed. The results of this study provide the useful information for designing the molecular structure of l -tyrosine-based polymers which possessing high thermal stability.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2024
·Vol. 32
·期 1
·1-13
·
IF 2.6
Song Jie,Wu Haodi,Niu Yuhua,Hui Baoli,Wang Youqian,Li Long
Soilless culture is gradually becoming a new direction in the development of agricultural cultivation. However, the synthetic substrates currently used suffer from the problems of being nutrient-less and non-degradable, which will ultimately lead to the misuse of chemical fertilizers and serious environmental pollution. In this study, L-Tyrosine(L-Tyr) was used as a nitrogen nutrient modifier, and L-Tyr-PCL-PCDL-PUF/KHA (L-Tyrosine-Polycaprolactone-Polycarbonate-Polyurethane Foam/Kalium Humate, LTPPPK) soilless substrate was prepared by using biodegradable polycaprolactone and potassium humate, a natural plant-stimulating hormone, as raw materials. The experimental results demonstrated that the incorporation of L-Tyr significantly enhanced the LTPPPK material's vesicular pore structure and morphology, characterized by an apparent density of 65.69 kg/m 3 , a porosity of 85.58%, a pore diameter of 0.96 ± 0.17 mm, a compressive strength of 0.015 MPa, and optimal thermal stability when the L-Tyr content was 3%. Additionally, L-Tyr enhanced the water absorption and retention capabilities, as well as the degradation performance of the material, achieving a maximum water absorption factor of 12.524 g/g. The degradation rate was found to be 10.95% after 6 months of degradation by N435 lipase, indicating that the material is environmentally friendly upon disposal. As a lettuce growing substrate, the LTPPPK material showed a 7.90% and 9.34% growth in root whisker and leaf width compared with the unmodified one after 42 days of lettuce growth, and the content of chlorophyll and soluble protein increased by 4.46% and 16.42%. It was shown that LTPPPK material can provide a certain amount of nitrogen and potassium for plant growth when used as lettuce cultivation substrate.
研究领域:
农业科学
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材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION
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2020
·
IF 2.69
Yasong Hu,Congcong Zhan,Anduo Zhou,Shanfeng Zhang,Juying Chen,Xia Huang
A novel amino acid-modified biomacromolecule was designed and synthesized as the quaternary ammonium salt chitosan grafted-tyrosine (CA-g-Tyr) suitable for biomedical applications. L-tyrosine was grafted onto the quaternary ammonium salt chitosan (CA) by N-(3-dimethylaminopropy)-N-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The chemical structure of CA-g-Tyr was confirmed by Fourier transform infrared (FTIR) spectroscopy and 13C-NMR. The change in the crystalline structure after the graft was characterized by differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). The surface wettability and moisturizing performance of the CA-g-Tyr were also characterized. The CA-g-Tyr film possessed good hydrophilicity, and the mechanical tensile experiments showed that the introduction of tyrosine gave CA mechanical properties more suitable for blood vessel. Cell experiments showed that the endothelial cells can adhere and proliferate better on the surface of a CA-g-Tyr film than CA. The results confirm the favorable properties and biocompatibility of CA–g-Tyr with potential applications as scaffolds for tissue engineering.
研究领域:
生物材料学
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医学
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高分子化学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL BIOCHEMISTRY
·
2018
·
IF 2.275
Xiao-Ling Tang,Hui Suo,Ren-Chao Zheng,Yu-Guo Zheng
Tyrosine phenol-lyase (TPL) naturally catalyzes the reversible β-elimination of l -tyrosine to phenol, pyruvate and ammonium. With its reverse reaction (synthetic activity), l -tyrosine and its derivatives could be synthesized with high atom economy, which are widely used in pharmaceutical industries . In this study, a high-throughput screening method for synthetic activity of TPL was developed. One of the substrate, sodium pyruvate was found to react with salicylaldehyde under alkali condition, forming a yellow color compound. The concentration of sodium pyruvate can be quantified according to the absorbance of the colorimetric compound at wavelength of 465 nm and the activity of TPL could be screened according to the decrease of the absorbance. After optimization of the colorimetric reaction conditions, the established high-throughput screening method was successfully used for screening of TPL with enhanced activity for l -DOPA synthesis. The confirmed sensitivity and accuracy demonstrated the feasibility and application potential of this screening method.
研究领域:
生物化学
·
制药工程
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2019
·
IF 9.518
Qin Zhu,Chu Liu,Li Zhou,Ling Wu,Kejun Bian,Julan Zeng,Jianxiu Wang,Zemeng Feng,Yulong Yin,Zhong Cao
Nanometer-sized copper sulfide has remarkable properties such as metal like electrical conductivity and electrocatalytic activity . In this work, ultrathin copper sulfide nanosheets (CuS NS) were synthesized and employed to modify on surface of glassy carbon electrode (GCE) combining with chitosan (CS) and acidified multi-walled carbon nanotubes (F-MWCNTs). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the shape of CuS NS was hexagon with side length of 13.33 ± 0.67 nm and thickness of 4.50 ± 0.58 nm. The electrochemical characteristics of different nanocomposite modified electrodes were examined by using cyclic voltammetry (CV) and differential pulse voltammetry (DPV), indicating that the modified electrode of CuS NS-CS/F-MWCNTs/GCE possessed good electrocatalytic activity towards oxidation of L-tyrosine (L-Tyr). Under the optimal condition, the modified electrode exhibited a wide linear response range for L-Tyr (0.08–1.0 μM) with a detection limit of 4.9 nM. No obvious interferences from coexisted two-fold of L-tryptophan and 50-fold of other amino acids could be observed, indicating its relatively good selectivity. The electrode also had good repeatability, reproducibility and stability. Compared with a commercial instrument analytical method, HPLC , the electrode can be successfully applied to the determination of L-Tyr in pig serums with a recovery rate of 95.7%–102.6%, and its test results are in good agreement with that of HPLC, showing its promising application value.
研究领域:
生物化学
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分析化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2021
·
IF 6.789
Hongji Li,Junfu Wang,Haoqi Fang,Hongda Xu,Haochen Yu,Tianyu Zhou,Chunbo Liu,Guangbo Che,Dandan Wang
The polyvinylidene difluoride (PVDF) membrane has received considerable attention as a flexible surface enhanced Raman scattering (SERS) substrate due to its excellent mechanical and physicochemical properties . However, the poor fouling resistance of PVDF membrane due to its intrinsic hydrophobic property limits its practical application. To address this, in this investigation, a SERS imprinted membrane is synthesized based on W 18 O 49 /Ag composites. Firstly, to promote hydrophilicity , N-vinyl-2-pyrrolidone (NVP) and triethoxyvinylsilane (VTES) are copolymerized by hydrolysis condensation and linked with engineered polyvinypyrrolidone (PVP) chains exposed on the surface of membrane. Furthermore, W 18 O 49 /Ag composites are dispersed on the membrane under the assistance of polydopamine (pDA) to promote the pollution resistance. Subsequently, in order to demonstrate the practical detection property, W 18 O 49 /Ag/PVDF membrane is selected as the SERS substrate to synthesize SERS imprinted membrane by precipitation polymerization for the selective detection of L-tyrosine. The characteristic results reveal that the SERS-imprinted membrane exhibits satisfactory hydrophilicity, and it can effectively degrade the pollutant molecules absorbed on its surface under ultraviolet light illumination. It is proved from the detection results that the LOD of WADP-MIMs for L-tyrosine reached 10 −9 mol L −1 when the concentration of L-tyrosine changed between 10 −3 –10 −9 mol L −1 . The correlation coefficient (R 2 ) is 0.994 and the limit of detection is 10 −9 mol L −1 . Meanwhile, it can be applied for the selective detection of L-tyrosine in mixture samples. Overall, this study presents a novel approach for the hydrophilic modification and pollution resistance enhancement of PVDF-based SERS imprinted membrane, which can be effectively utilized for the selective detection of practical samples.
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2020
·
IF 3.557
Xiao-Qin Wu,Pei-Qi Feng,Zhiqiang Guo,Xuehong Wei
An electrochemical biosensor based on a water-stable one-dimensional double-chain Cu(II) metal–organic framework (Cu-MOF) directly was constructed for efficiently recognizing l-tyrosine (l-Tyr) in biomimic environments. Cu-MOF: {[Cu(bpe)(fdc) (H2O)(DMF)]·0.5H2O}n (bpe = 1,2-di(4-pyridyl)ethylene, H2fdc = 2,5-furandicarboxylic acid, namely, Cu-1) was synthesized by a hydrothermal method. It was characterized by IR, scanning electron microscopy, atomic force microscopy, and PXRD techniques. Cu-1 exhibited extreme solvent and thermal stability as well as excellent electroconductive character. It was coated on a glassy carbon electrode (GCE) surface to prepare an electrochemical biosensor (Cu-1/GCE) which showed preferable biosensing ability toward l-Tyr. This Cu-MOF electrochemical biosensor showed simple operation and high sensitivity toward l-Tyr in the concentration range from 0.01 to 0.09 mM. The detection limit is 5.822 μM. Furthermore, Cu-1/GCE showed extremely excellent selectivity to l-Tyr in a biomimic environment with several amino acid interferents. This new strategy exhibits great potential applications for designing MOFs with excellent electrochemical activity.
研究领域:
分析化学
·
生物医学工程
·
材料科学
✓ 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）