JOURNAL OF MOLECULAR LIQUIDS
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2024
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IF 5.3
Kexin Yang,Yanyan Huang,Huan Lin,Yiming Zhao,Yushan Hou,Jie Zhou,Chenxi Zhao,Chenyu Qi,Yaowei Zhang,Lingyun Li,Chen Yin,Gaofeng Cao,Guangyang Liu,Miaomiao Liu,Donghui Xu
Inspired by the surface structure of mussel, a novel bionic adsorbent (MPN@COFs) was prepared using an in situ synthetic strategy for the selective adsorption of caffeine and the physicochemical structure, surface morphology and composition of were characterized by scanning electron microscopy, Fourier-transform infrared spectrometry, X-ray photoelectron spectroscopy. The analytical data showed that the specific surface area of MPN @ COF was as high as 133.62 m 2 /g, which was stable and adaptable to acid and alkaline environments, with a adsorption rate of 78 %, and still maintained a high adsorption rate after reuse for three times. The adsorption isotherms and adsorption kinetics fit the Langmuir model and the quasi-secondary kinetic model better, respectively. Compared with single COFs and MPN, the adsorption efficiency of MPN@COFs increased by 40.54 % and 57.65 %, respectively. Moreover, the composite material could be reused three times, the HPLC-MS/MS method established in this study has high sensitivity, and this rapid detection technique can provide strong support for the detection of caffeine in beverages and the removal of caffeine from tea and its products.
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
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2018
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IF 3.129
Lujing Xu,Guobin Xia,Zisheng Luo,Songbai Liu
In this study, an effective ultra-high performance liquid chromatography (UHPLC) method for simultaneous determination of 15 constituents of catechins, caffeine, gallic acid and theaflavins was developed. Employing the developed UHPLC method, the contents of the 15 constituents were analyzed in 245 samples of 6 types of Chinese teas collected from different places. The catechin contents in these samples ranged from 16.50 to 94.35 mg/g. Theaflavins were not detected in green tea and white tea, and caffeine did not strongly relate to germplasm resource or fermentation degree. Principal component analysis (PCA) of UHPLC data revealed that white, oolong and green tea samples could be clustered closely, demonstrating notable difference of functional components between the three types of teas resulting from preparation process and varieties. The constituent profile could be primarily attributed to the structural transformation of catechins and pigments during tea processing. This study would advance our understanding of chemical profile of Chinese teas afforded by different processing technologies.
研究领域:
食品科学
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分析化学
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植物化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL LETTERS
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2023
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IF 2
Xinlei Zhang,Wenbao Jia,Xinru Tang,Qing Shan,Qiyan Chen,Can Cheng,Jinfa Shao,Yongsheng Ling,Daqian Hei
Teas of the same type in a small growing area are generally similar, and identification of their detailed geographic origin is challenging and interesting. In this study, a convenient method for distinguishing Pu-erh teas from nearby locations was developed by combining two spectroscopic techniques with chemometric methods. The distinction was based on the difference in the mineral elements and organic metabolites from tea infusions. First, Pu-erh tea was infused with water at 90 °C for 30 min. Total reflection X-ray fluorescence and ultraviolet-visible (UV-Vis) spectroscopies were used to determine the elements (P, S, K, Ca, Mn, and Ni) and organic metabolites (caffeine and polyphenols), respectively. Chemometric methods were applied to classify the origin based on the component. The proposed method was used to test samples collected from 10 mutually adjacent high-altitude villages in Mengku, Lincang, Yunnan, China. The developed user-friendly method was successfully used for the rapid evaluation of the composition, enabling the identification of the geographic origins of Pu-erh tea. Mn, caffeine, and polyphenols were found to be the key origin markers. Compared to principal component analysis, linear discriminant analysis models exhibited high discrimination performance with 100% predictive ability to distinguish the geographic origins of Pu-erh teas over a small production area. This rapid and simple method may be used to solve classification problems in tea quality control and management.
研究领域:
食品科学
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分析化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
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2021
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IF 6.475
Cheng Guo,Jing Li,Yijie Chen,Fang Geng,Bin Li
Epigallocatechin gallate (EGCg) and methylxanthines are representative bioactive compounds in tea leaves, the strong affinity between them will elicit destruction of tea quality. In order to elucidate the mechanism of complexation between EGCg and methylxanthines, we compared the bindings of theophylline and caffeine to EGCg by nuclear magnetic resonance (NMR), molecular docking and isothermal titration calorimetry (ITC). The results revealed that the stoichiometries of caffeine to EGCg and theophylline to EGCg were both 1:1. Caffeine and theophylline were captured in the hydrophobic space formed by aromatic rings of EGCg. The affinity between EGCg and caffeine was stronger than that between EGCg and theophylline, which could be partially attributed to the two extra CH-π interactions between N 7 -Me of caffeine and aromatic rings of EGCg. Furthermore, the results of ITC were agreed well with NMR and molecular docking, indicating that ITC was possible to accurately evaluate the complexation.
研究领域:
食品科学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WORLD JOURNAL OF GASTROENTEROLOGY
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2014
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IF 2.433
Jia-Yi Ma,Run-Hua Li,Kun Huang,Gao Tan,Chen Li,Fa-Chao Zhi
AIM: To investigate the possible role of chitinase 3-like-1 (CHI3L1) in the progression of colitis-associated carcinoma (CAC). METHODS: Thirty-four Balb/c mice were randomly assigned to five groups, including the control, CAC control, CAC + caffeine, colitis control and colitis + caffeine. Three animals were sacrificed every two weeks for blinded macroscopic inspection, histological analysis, and total RNA extraction. An immunofluorescent assay was performed using specimens from the colitis control and colitis + caffeine groups to investigate whether the protective effect of caffeine was associated with less oxidative DNA damage. In vitro , HT29 cells pre-stimulated with different concentrations of recombinant CHI3L1 protein and H 2 O 2 were loaded with the DCFH-DA fluorescent probe to determine the effect of CHI3L1 on intracellular reactive oxygen species production. RESULTS: CHI3L1 mRNA was increased during the progression of colon carcinogenesis. Tumors were mostly located in the distal end of the colon where the expression of CHI3L1 was higher than in the proximal colon. Caffeine-treated mice developed fewer tumors and milder inflammation than untreated mice. CHI3L1 protein increased reactive oxygen species in HT29 cells when exposed to H 2 O 2 . CONCLUSION: Caffeine reduces tumor incidence by decreasing oxidative DNA damage. CHI3L1 may contribute to CAC by increasing reactive oxygen species production.
研究领域:
肿瘤学
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消化病学
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分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Environmental Science and Ecotechnology
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2024
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IF 14
Zhenglu Wang,Jindong Xu,Wei Du
The coexistence of caffeine (CF) and ketamine (KET) in surface waters across Asia has been widely reported. Previous studies have implied that CF and KET may share a mechanism of action. However, the combined toxicity of these two chemicals on aquatic organisms remains unclear at environmental levels, and the underlying mechanisms are not well understood. Here we demonstrate that KET antagonizes the adverse effects of CF on zebrafish larvae by modulating the gamma-aminobutyric acid (GABA)ergic synapse pathway. Specifically, KET (10–250 ng L −1 ) ameliorates the locomotor hyperactivity and impaired circadian rhythms in zebrafish larvae induced by 2 mg L −1 of CF, showing a dose-dependent relationship. Additionally, the developmental abnormalities in zebrafish larvae exposed to CF are mitigated by KET, with an incidence rate reduced from 26.7% to 6.7%. The competition between CF and KET for binding sites on the GABA-A receptor ( in situ and in silico ) elucidates the antagonistic interactions between the two chemicals. Following a seven-day recovery period, the adverse outcomes of CF exposure persist in the fish, whereas the changes observed in the CF + KET groups are significantly alleviated, especially with KET at 10 ng L −1 . Based on these results, it is imperative to further assess the environmental risks associated with CF and KET co-pollution. This pilot study underscores the utility of systems toxicology approaches in estimating the combined toxicity of environmental chemicals on aquatic organisms. Moreover, the nighttime behavioral functions of fish could serve as a sensitive biomarker for evaluating the toxicity of psychoactive substances.
研究领域:
生态毒理学
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神经生物学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
IUCrJ
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2021
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IF 4.769
Yanming Xia,Yuanfeng Wei,Hui Chen,Shuai Qian,Jianjun Zhang,Yuan Gao
Recently, cocrystallization has been widely employed to tailor physicochemical properties of drugs in the pharmaceutical field. In this study, cocrystallization was applied to separate natural compounds with similar structures. Three flavonoids [baicalein (BAI), quercetin (QUE) and myricetin (MYR)] were used as model compounds. The coformer caffeine (CAF) could form cocrystals with all three flavonoids, namely BAI-CAF (cocrystal 1), QUE-CAF (cocrystal 2) and MYR-CAF (cocrystal 3). After adding CAF to methanol solution containing MYR and QUE (or QUE and BAI), cocrystal 3 (or cocrystal 2) preferentially formed rather than cocrystal 2 (or cocrystal 1), indicating that flavonoid separation could be achieved by competitive cocrystallization. After co-mixing the slurry of two flavonoids with CAF followed by centrifugation, the resolution ratio that could be achieved was 70-80% with purity >90%. Among the three cocrystals, cocrystal 3 showed the lowest formation constant with a negative Gibbs free energy of nucleation and the highest energy gap. Hirshfeld surface analysis and density of states analysis found that cocrystal 3 had the highest strong interaction contribution and the closest electronic density, respectively, followed by cocrystal 2 and cocrystal 1, suggesting CAF could competitively form a cocrystal with MYR much more easily than QUE and BAI. Cocrystallization is a promising approach for green and effective separation of natural products with similar chemical structures.
研究领域:
药物化学
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天然产物化学
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
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2014
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IF 4.517
Lin Jiang,Yaping Ding,Feng Jiang,Li Li,Fan Mo
A nitrogen-doped graphene/carbon nanotubes (NGR–NCNTs) nanocomposite was employed into the study of the electrochemical sensor via electrodeposition for the first time. The morphology and structure of NGR–NCNTs nanocomposite were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Meanwhile, the electrochemical performance of the glassy carbon electrode (GCE) modified with electrodeposited NGR–NCNTs (ENGR–NCNTs/GCE) towards caffeine (CAF) and vanillin (VAN) determination was demonstrated by cyclic voltammetry (CV) and square wave voltammetry (SWV). Under optimal condition, ENGR–NCNTs/GCE exhibited a wide linearity of 0.06–50 μM for CAF and 0.01–10 μM for VAN with detection limits of 0.02 μM and 3.3 × 10 −3 μM, respectively. Furthermore, the application of the proposed sensor in food products was proven to be practical and reliable. The desirable results show that the ENGR–NCNTs nanocomposite has promising potential in electrocatalytic biosensor application.
研究领域:
分析化学
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材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Saudi Chemical Society
·
2016
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IF 1.978
Jian Wang,Yabing Sun,Hao Jiang,Jingwei Feng
s In this research, dielectric barrier discharge plasma was developed to cooperate with goethite for removing caffeine in aqueous solution. Goethite was characterized by X-ray diffraction and scanning electron microscopy. The effects of input power, initial concentration and catalysts concentration on the removal efficiency of caffeine were evaluated. Furthermore, the degradation pathways of caffeine were also discussed preliminarily. In the case of caffeine concentration at 50 mg L −1 , the degradation efficiency of caffeine was improved from 41% to 94% after 24 min on the conditions of input power of 75 W by combining goethite catalysts (2.5 g L −1 ), while the energy efficiency could be enhanced 1.6–2.3 times compared to the single DBD reactor. The reaction mechanism experiments demonstrated that attack by hydroxyl radical and ozone was the main degradation process of caffeine in aqueous solution. These studies also provided a theoretical and practical basis for the application of DBD-goethite in treatment of caffeine from water.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2019
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IF 2.813
Mingxue Li,Ligai Bai,Shan Peng,Fanrong Sun,Laisen Wang,Haiyan Liu,Hongyuan Yan
A polymer-based chromatographic monolithic column was prepared via in-situ radical polymerization using tetrahydrofurfuryl methacrylate as the monomer . The homemade column was used for the separation and quantitative analysis of alkaloids, including piperine from Piper longum (fruit of Piper longum Linn .) and pepper (fruit of Piper nigrum L. ), hydroxy-α-sanshool, and hydroxy-γ-sanshool from zanthoxylum (fruit of Zanthoxylum bungeanum Maxim ), as well as caffeine from Wuyi rock tea. The chromatographic fractions were identified by mass spectrometry. Single factor test and orthogonal test were both carried out to optimize the extraction conditions. The method validation indicated that the accuracy represented by spiked recovery ranged in 98.89%–102.06%, the correlation coefficients in 0.99986–0.99999. These results show that the prepared monolithic column can be successfully used to quantitatively analyse alkaloids from the real medicinal and edible plant foods with reversed-phase mechanism, which can avoid the long analytical time using traditional packed C18 column. The present method is a simple, and inexpensive method for quantitatively analysing alkaloids from medicinal and edible plant foods, exhibiting good specificity and durability.
研究领域:
药学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2013
·
IF 2.672
Yangyang Gao,Huan Wang,Liping Guo
In this work, a glassy carbon electrode (GCE) modified with large mesoporous carbon and Nafion composites (LMC/Nafion) was constructed and used for simultaneous determination of theophylline (TP) and caffeine (CF). The electrochemical behaviors of TP and CF on the LMC/Nafion/GCE were carefully investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The results show that the DPV peaks of the two analytes can be distinguished at the modified electrode with peak-to-peak separation about 150 mV, which means that LMC/Nafion/GCE is suitable for simultaneous determination of TP and CF. Under the optimized condition, the detection limits of TP and CF were 0.37 and 0.47 μM ( S / N = 3) with linear ranges of 0.8–180.0 μM and 1.3–230.0 μM, respectively. The proposed method was successfully applied to the simultaneous determination of TP and CF in human blood serum and beverages with reliable recovery.
研究领域:
分析化学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2025
·
IF 8
Yurui Song,Jingzhe Li,Qiayun Ding,Xiang Yang,Jieyao Yu,Yanyan Zhang,Yijun Wang,Xiaochun Wan,Xiaoting Zhai
Fenghuang Dancong tea (FHDC) is a renowned oolong tea in China due to its complex aroma characteristics. However, the aroma differences between FHDC teas with typical aroma profiles are still unknown. This study employed the sensomics approach to characterize the key odorants in three distinct FHDC samples with aroma types of Yashi, Huangzhi, and Milan, respectively. The aroma profile analysis showed the three samples evoked coconut milk-like, flowery/sweety, and fruity/sweety smelling, respectively. The quantitative analysis, odor activity values, and chemometrics showed that jasmine lactone, ( Z )-jasmone, linalool, γ -hexalactone were key aroma markers to identify the three samples. Besides, the odor thresholds determination of the four aroma markers present that the addition of caffeine in water obviously lowered their respective odor thresholds, revealing the role of caffeine in strengthening the intensities of sweety, flowery and fruity notes tea infusion. This research not only offered a valuable insight into the identification of FHDC’s aromatic complexity but also supported the precise aroma classification and optimization.
研究领域:
食品科学
·
茶叶研究
·
感官科学
✓ 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）