MICROCHEMICAL JOURNAL
·
2020
·
IF 3.594
Hui Ma,Ronghua Zhang,Qi Kang,Tao Wang,Jianhong Xiao,Xuezhi Li,Li Yu
A facile, low-cost and label-free liquid crystals (LCs) sensing platform laden with Cu(ClO 4 ) 2 was herein established for detection and distinction of sulfhydryl amino acids, namely cysteine (Cys) and homocysteine (Hcy). When introducing Cys or Hcy to the fluid interface with Cu(ClO 4 ) 2 , the optical appearance of LCs exhibited a bright-to-dark transition, which coupled to the interactions between Cu 2+ and the sulphydryl of amino acids. Concomitantly with, the orientation of LCs varied from tilted to homeotropic state. Besides, this sensor system did not respond to other nineteen amino acids that make up human proteins. The detection limit of Cys and Hcy is around 0.01 mg/mL (~82.5 μM) and 0.05 mg/mL (~370.0 μM), respectively. Compared with Cys, the as-prepared LCs sensing platform shows a higher detection limit and longer response time for Hcy, based on which these two sulfhydryl amino acids can be distinguished from each other. This can be attributed to the additional methylene for Hcy, resulting in formation of a five-membered ring Hcy thiolactone which may not chelate with Cu 2+ . The LCs-based analytical platform constructed in this work can provide a convenient and label-free method for detecting and differentiating sulfhydryl amino acids.
研究领域:
分析化学
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生物传感
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医学检测
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2023
·
IF 6.1
Yue Luo,Siyue Zhu,Jie Peng,Heping Cui,Qingrong Huang,Baojun Xu,Chi-Tang Ho
Amadori rearrangement products (ARPs), as intermediates of the Maillard reaction (MR), are potential natural flavor additives but there is a lack of investigation especially in oligopeptide-ARPs. This study for the first time conducted a systematic analysis in comparing ARPs of glycine, diglycine, triglycine, and glucose to corresponding classic MR systems, including production, stability, and flavor analysis. The ARPs were effectively produced by prelyophilization with heating at 70 °C for 60 min and purified to 96% by a two-step purification method. Correlated with the stability order of amino compounds (glycine > diglycine > triglycine), the stability order of ARPs was Gly-ARP > Digly-ARP ≈ Trigly-ARP. In a negative correlation with heating temperature and time, ARPs were less stable than original amino compounds at high temperatures (100, 130, and 160 °C). ARPs exhibited better flavor formation ability in pyrazines and furans than MR systems, with similar flavor compositions but different preferences. Diglycine- and triglycine-ARPs exhibited better flavor formation efficiency than glycine-ARP. Heating temperature and time, initial pH, and carbon chain length were found to be the parameters that affect the stability and flavor formation of ARPs. This study suggested that ARPs, especially peptide-ARPs, have great potential for usage as food flavor additives in the future.
研究领域:
食品科学
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化学
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DOI
PubMed
高影响因子
CHROMATOGRAPHIA
·
2023
·Vol. 86
·期 7
·541-551
·
IF 1.7
Guo Xinyuan,Shang Panpan,Wei Benben,Du Wenrong,Lan Yong,Bai Ligai,Qiao Xiaoqiang,Ma Zhengyue
This study presents the development of three new chiral stationary phases. Three new peptide chiral stationary phases with a main chain of l- proline, l- phenylalanine, l- valine and l- leucine and different terminals of l- citrulline, l- lysine and l- tryptophan immobilized on 3-aminopropyltrimethoxysilane modified silica gel were prepared; furthermore, successful analyses and characterizations were conducted using Fourier transform infrared spectra, elemental analysis, and thermogravimetric analysis. After this, the enantioselective performance of the three peptide stationary phases columns was evaluated. The evaluation used nine racemic compounds under normal-phase high-performance liquid chromatography mode. Optimized enantiomeric separation conditions were established. Under these conditions, the resolutions of flurbiprofen, naproxen, benzoin, 1 ,1ʹ-bi-2-naphthol and ketoprofen on the CSP-1 column were 1.61, 2.0, 0.62, 0.52 and 1.20, respectively. In addition, the reproducibility of the CSP-1 column was also investigated. The results of the investigation illustrated that the stationary phases have good reproducibility (RSD = 0.12%, n = 5).
研究领域:
分析化学
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色谱学
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材料科学
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分离科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Jiayue Dong,Peizeng Yang,Guoqiang Liu,Deyang Kong,Yuefei Ji,Junhe Lu
In this study, the transformation of five amino acids (AAs), i.e., glycine (GLY), alanine (ALA), serine (SER), aspartic acid (ASP), and methionine (MET), in a heat activated peroxydisulfate (PDS) oxidation process was investigated. Experimental data showed that the nitrogen in the AA molecules was oxidized to NH 4 + and nitrate (NO 3 - ) sequentially. However, in the presence of natural organic matter (NOM), nitrophenolic byproducts including 4-nitrophenol, 2,4-dinitrophenol, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid were formed. The nitrogen dioxide radical (NO 2 • ) generated during the transformation of NH 4 + to NO 3 - was presumed to be the key nitrating agent. It reacted with phenolic moieties in NOM and was transformed to nitrophenolic byproducts. Among the selected AAs, SER showed the highest nitrophenolic byproducts formation potential. A total yield of 0.258 μM was observed at the condition of 0.1 mM SER, 5 mg/L (as TOC) NOM, 2 mM PDS, and pH 7.0. The formation from GLY and ALA was lowest, only 0.009 μM detected under the same conditions. The nitrophenolic byproducts formation potential of the AAs was positively related to their reactivity toward SO 4 •- and can be explained by the local nucleophilicity index ( N k ). These findings underline the potential risks in the application of SO 4 •- based oxidation technology .
研究领域:
环境化学
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水处理
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氧化过程
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DOI
PubMed
高影响因子
eFood
·
2024
·Vol. 5
·期 2
·e143
·
IF 4
Xiaomei Lv,Haolin Zhang,Qiuyi Lin,Ruiwei Xie,Bing-Huei Chen,Yu-Wen Lai,Hui Teng,Lei Chen,Hui Cao
Polycyclic aromatic hydrocarbons (PAHs) are found in many common foods and increase the risk of cancer in humans. This study systematically screened the components that may be related to the formation of PAHs by an excessive addition of 19 amino acids and glucose in the beef patties. Phenylalanine and glucose exhibited the potential as promoters of PAHs, while lysine, aspartic acid, glutamic acid, valine, and methionine exhibited excellent potential as inhibitors of PAHs. Subsequently, a chemical model containing phenylalanine and glucose was established to confirm their roles as precursors of PAHs. The formation mechanism of PAHs showed that naphthalene was first formed as a basic structure, and then, PAHs with more rings were further formed through substitution, addition reactions, or intramolecular cyclization reactions. The mitigative effects of four flavonoids on total PAH contents were in the order: kaempferol > naringenin (better for individual PAH) > myricetin > quercetin (contradictory), which suggested that the antioxidant ability or radical scavenging capacity of flavonoids may be one of the pathways for PAH inhibition.
研究领域:
食品科学
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化学
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营养学
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毒理学
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产品关联
DOI
高影响因子
BIOTECHNOLOGY LETTERS
·
2020
·Vol. 42
·期 8
·1501-1511
·
IF 1.977
Chang Ya-Wen,Zhang Jian-Dong,Yang Xiao-Xiao,Li Jing,Gao Li-Li,Huang Shuang-Ping,Guo Xing-Mei,Zhang Cao-Feng,Chang Hong-Hong,Xu Jian-He
Objectives To screening of bacteria with cyclic amino alcohol deamination activity for enantioselective synthesis of chiral cyclic β-amino alcohols. Results A new strain named Arthrobacter sp. TYUT010-15 with the ( R )-selective deamination activity of cyclic β-amino alcohol has been isolated from nature via a high throughput solid-phase screening method. The reaction conditions of TYUT010-15 were optimized. Using the resting cell of TYUT010-15 as the catalyst, kinetic resolution of trans -2-aminocyclopentanol, trans -2-aminocyclohexanol and cis -1-amino-2-indanol was carried out to afford (1 S , 2 S )- trans -2-aminocyclopentanol, (1 S , 2 S )- trans -2-aminocyclohexanol and (1 R , 2 S )- cis -1-amino-2-indanol in > 99% ee and 49.6–50% conversion. Four aromatic β-amino alcohols and two amines were also resolved, ( S )-β-amino alcohols and ( R )-amines were obtained in > 99% ee. Preparation experiment was conducted with 200 mM (23.2 g L −1 ) racemic trans -2-aminocyclohexanol, yielding the desired (1 S , 2 S )- trans -2-aminocyclohexanol in 40% isolated yield, > 99% ee and 5.8 g L −1 d −1 space time yields. Conclusions This study provides a high throughput solid-phase method for screening of bacteria with cyclic amino alcohol deamination activity and a first example for practical preparation of chiral cyclic β-amino alcohol by Arthrobacter sp. TYUT010-15.
研究领域:
微生物学
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有机化学
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生物催化
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手性化学
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产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
·
2024
·
IF 2.5
He Wang,Haidu Yuan,Jianhao Zhang,Wenjing Yan
Bacterial infections are becoming a significant threat to global human health due to the growing prevalence of biofilm-related infections and the rise in antibiotic resistance. D/ l -cysteine functionalized chiral gold nanoparticles (D/P-Au NPs or L/P-Au NPs) have demonstrated a potent antibacterial effect against E. coli , while the mechanism remains to be elucidated through additional research. Threonine deaminase (TD) is a crucial enzyme involved in branched-chain amino acid (BCAA) biosynthesis in E. coli and is involved in cysteine's antimicrobial effects. This study investigated the interaction between chiral Au NPs (D/P-Au NPs or L/P-Au NPs) and TD as well as its effect on enzyme activity. It demonstrates that chiral Au NPs interact with TD through hydrophobic forces, forming a ground state complex that induces changes in the secondary structure of TD and reduces enzyme activity in a concentration-dependent manner. We found that the exogenous supplementation of isoleucine and valine (2 mg/mL) significantly reduced the antibacterial activity of chiral Au NPs, especially for L/P-Au NPs. The proteomics results indicate that the expression of ilvA and ilvB was down-regulated after L/P-Au NPs treatment, which would interfere with the synthesis of BCAAs. These results demonstrate that chiral Au NPs cause cell death of E. coli partly due to inhibition of TD enzyme activity and the synthesis of branched-chain amino acids.
研究领域:
微生物学
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纳米生物学
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生物化学
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DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Chunpeng Chai,Zhenqian Ma,Xuan Yin,Haosheng Pang
Self-healing polyurethane is a matrix material that can effectively extend the service life of composite materials. The layered two-dimensional Ti3C2Tx material has weak interlayer van der Waals forces, which can undergo slip and form transfer films during friction, reducing shear strength and improving the lubrication performance of the material. Therefore, we introduced two-dimensional Ti3C2Tx into a self-healing polyurethane matrix to improve the lubrication performance of the matrix material. A dual-ion self-healing polyurethane (SPU) was prepared using N-methyl diethanolamine, hexamethylene diisocyanate, and 1,3-propane sultone as raw materials. Ti3C2Tx was prepared by chemical etching, and NH2–Ti3C2Tx was obtained by chemically grafting amino groups onto the surface of Ti3C2Tx using amino-propyltriethoxysilane. Then, it was mixed into the SPU matrix to obtain the NH2–Ti3C2Tx/SPU composite material. Compared with pure SPU, the friction coefficient and wear rate of the system were reduced by 79.7% and 97.8%, respectively. Under 75%RH and 20 °C conditions, self-healing could be achieved rapidly within 5 min, with a self-healing efficiency of 84.4%. The kind of self-lubricating and self-healing polyurethane modified by amination-Ti3C2Tx is expected to be applied in automotive, electronics, and biomedicine.
研究领域:
材料科学
·
摩擦学
·
纳米复合材料
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2023
·
IF 6.1
Xue Xia,Tong Zhou,Jingyang Yu,Heping Cui,Foxin Zhang,Khizar Hayat,Xiaoming Zhang,Chi-Tang Ho
The dynamic changes in fluorescence intensity of the Maillard reactions of l-alanyl-l-glutamine (Ala-Gln)/Diglycine (Gly-Gly)/glycyl-l-glutamine (Gly-Gln) and glucose were investigated. It was found that the fluorescence intensity would increase with the reaction time; however, it would decrease after longer heating at higher temperatures, which was accompanied by rapid browning. The strongest intensity occurred at 45, 35, and 35 min at 130 °C for Ala-Gln, Gly-Gly, and Gly-Gln systems, respectively. The simple model reactions of Ala-Gln/Gly-Gly and dicarbonyl compounds were selected to reveal the formation and mechanism of fluorescent Maillard compounds. It was confirmed that both GO and MGO could react with peptides to form fluorescent compounds, especially GO, and this reaction was sensitive to temperature. The mechanism was also verified in the complex Maillard reaction of pea protein enzymatic hydrolysates.
研究领域:
食品化学
·
物理化学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FLUORESCENCE
·
2025
·
IF 3.1
Chen Xin,Wang Qing-wan,Zhan Tong-ling,Sun Yue,Zhang Xiao-rui,Liu Kun,Liu Xiao-wu
Nitrogen@Carbon quantum dots (N@CQDs) are prepared using microwave hydrothermal method, and polyvinylpyrrolidone (PVP) and melamine are used as mixed C source and N source. Microwave reaction conditions of preparing the N@CQDs are 170 ℃ and 3 h. This N@CQDs are are used as fluorescence probe for detection of amino acids. The N@CQDs can recognize L-alanine in water solution, and simultaneously recognize both L-methionine and L-cysteine in dimethyl sulfoxide (DMSO) solution. The linear ranges for L-alanine, L-methionine and L-cysteine are 0–15 µM, 2–50 µM and 0–17 µM, respectively. While limits of detection (LOD) for them are 11.092 nM, 7.8067 nM and 0.67476 nM, respectively. Compared to presently available detection methods, as-prepared N@CQDs have the advantage of high sensitivity and selectivity. Furthermore, coexistence of other amino acids has minimal interference in the detection of L-alanine, L-methionine and L-cysteine. For the as-prepared N@CQDs, solvent plays important roles in influencing the identification of amino acid types and detection sensitivity.
研究领域:
分析化学
·
生物传感
·
材料科学
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产品关联
DOI
PubMed
高影响因子
Metabolites
·
2019
·Vol. 9
·期 4
·77
·
IF 3.303
Xiao Pu,Yiqiao Gao,Ruiting Li,Wei Li,Yuan Tian,Zunjian Zhang,Fengguo Xu
Cytochrome P450 1A2 (CYP1A2) is one of the major CYP450 enzymes (CYPs) in the liver, and participates in the biotransformation of various xenobiotics and endogenous signaling molecules. The expression and activity of CYP1A2 show large individual differences, due to genetic and environmental factors. In order to discover non-invasive serum biomarkers associated with hepatic CYP1A2, mass spectrometry-based, untargeted metabolomics were first conducted, in order to dissect the metabolic differences in the serum and liver between control rats and β-naphthoflavone (an inducer of CYP1A2)-treated rats. Real-time reverse transcription polymerase chain reaction and pharmacokinetic analysis of phenacetin and paracetamol were performed, in order to determine the changes of mRNA levels and activity of CYP1A2 in these two groups, respectively. Branched-chain amino acids phenylalanine and tyrosine were ultimately focalized, as they were detected in both the serum and liver with the same trends. These findings were further confirmed by absolute quantification via a liquid chromatography–tandem mass spectrometry (LC-MS/MS)-based targeted metabolomics approach. Furthermore, the ratio of phenylalanine to tyrosine concentration was also found to be highly correlated with CYP1A2 activity and gene expression. This study demonstrates that metabolomics can be a potentially useful tool for biomarker discovery associated with CYPs. Our findings contribute to explaining interindividual variations in CYP1A2-mediated drug metabolism.Keywords:CYP1A2;endogenous biomarkers;metabolomics;branched-chain amino acids;phenylalanine;tyrosine
研究领域:
药理学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2025
·
IF 4.2
Xin Lin,Fang-Fang Shen,Ren-Jie Song
In this study, two novel fluorescent probes, H 1 /G and H 2 /G, were constructed using two alkyl-substituted cucurbit[6]urils (CB[6]s), H 1 and H 2 , and a cationic dye guest, G. The G molecules were encapsulated within the cavities of CB[6] hosts, forming 1:1 host–guest complexes. While free G molecules exhibited negligible fluorescence in solution, the inclusion complexes demonstrated a strong fluorescence signal (618 nm). The detection limits for glutamic acid (Glu) recognition by the two probes were as low as 2.98 × 10 −7 M and 4.20 × 10 −7 M, respectively. Notably, although the two modified CB[6]s differed by only a single substituent, their resulting probes demonstrated different degrees of amino acid recognition ability. The H 2 /G probe was capable of recognizing both Glu and lysine (Lys), while the H 1 /G probe detected only Glu. By employing structurally modified CB[6]s as hosts and constructing CB[6]-based fluorescent probes capable of selectively recognizing non-aromatic amino acids, this study paves the way for the biological applications of CB[6]-based supramolecular host–guest systems.
研究领域:
超分子化学
·
分析化学
·
生物有机化学
·
荧光传感
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）