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- UHPLC determination of catechins for the quality control of green tea.
- Naldi M, Fiori J, Gotti R, Périat A, Veuthey JL, Guillarme D, Andrisano V.Author information Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy.AbstractAn ultra-high performance liquid chromatography (UHPLC) with UV detection method was developed for the fast quantitation of the most represented and biologically important green tea catechins and caffeine. UHPLC system was equipped with C18 analytical column (50mm×2.1mm, 1.8μm), utilizing a mobile phase composed of pH 2.5 triethanolamine phosphate buffer (0.1M) and acetonitrile in a gradient elution mode; under these conditions six major catechins and caffeine were separated in a 3min run. The method was fully validated in terms of precision, detection and quantification limits, linearity, accuracy, and it was applied to the identification and quantification of catechins and caffeine present in green tea infusions. In particular, commercially available green tea leaves samples of different geographical origin (Sencha, Ceylon Green and Lung Ching) were used for infusion preparations (water at 85°C for 15min). The selectivity of the developed UHPLC method was confirmed by comparison with UHPLC-MS/MS analysis. The recovery of the main six catechins and caffeine on the three analyzed commercial tea samples ranged from 94 to 108% (n=3). Limits of detection (LOD) were comprised in the range 0.1-0.4μgmL(-1). An orthogonal micellar electrokinetic (MEKC) method was applied for comparative purposes on selectivity and quantitative data. The combined use of the results obtained by the two techniques allowed for a fast confirmation on quantitative characterization of commercial samples.
- Journal of pharmaceutical and biomedical analysis.J Pharm Biomed Anal.2014 Jan;88:307-14. doi: 10.1016/j.jpba.2013.08.054. Epub 2013 Sep 12.
- An ultra-high performance liquid chromatography (UHPLC) with UV detection method was developed for the fast quantitation of the most represented and biologically important green tea catechins and caffeine. UHPLC system was equipped with C18 analytical column (50mm×2.1mm, 1.8μm), utilizing a mobile
- PMID 24103292
- Simultaneous determination of caffeine, theophylline and theobromine in food samples by a kinetic spectrophotometric method.
- Xia Z, Ni Y, Kokot S.Author information State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.AbstractA novel kinetic spectrophotometric method was developed for the simultaneous determination of caffeine, theobromine and theophylline in food samples. This method was based on the different kinetic characteristics between the reactions of analytes with cerium sulphate in sulphuric acid and the associated change in absorbance at 320 nm. Experimental conditions, the effects of sulphuric acid, cerium sulphate and temperature, were optimised. Linear ranges (0.4-8.4 μg mL(-1)) for all three analytes were established, and the limits of detection were: 0.30 μg mL(-1) (caffeine), 0.33 μg mL(-1) (theobromine) and 0.16 μg mL(-1) (theophylline). The recorded data were processed by partial least squares and artificial neural network, and the developed mathematical models were then used for prediction. The proposed, novel method was applied to determine the analytes in commercial food samples, and there were no significant differences between the results from the proposed method and those obtained by high-performance liquid chromatography.
- Food chemistry.Food Chem.2013 Dec 15;141(4):4087-93. doi: 10.1016/j.foodchem.2013.06.121. Epub 2013 Jul 4.
- A novel kinetic spectrophotometric method was developed for the simultaneous determination of caffeine, theobromine and theophylline in food samples. This method was based on the different kinetic characteristics between the reactions of analytes with cerium sulphate in sulphuric acid and the associ
- PMID 23993589
- Simultaneous quantification of caffeine and its three primary metabolites in rat plasma by liquid chromatography-tandem mass spectrometry.
- Choi EJ, Bae SH, Park JB, Kwon MJ, Jang SM, Zheng YF, Lee YS, Lee SJ, Bae SK.Author information College of Pharmacy, The Catholic University of Korea, Bucheon, Gyeonggi-do 420-743, Republic of Korea.AbstractA rapid, sensitive, simple and accurate LC-MS/MS method for the simultaneous quantitation of caffeine, and its three primary metabolites, theobromine, paraxanthine, and theophylline, in rat plasma was developed and validated. Chromatographic separation was performed on an Agilent Poroshell 120 EC-C18 column using 1 μg/mL acetaminophen as an internal standard. Each sample was run at 0.5 mL/min for a total run time of 7 min/sample. Detection and quantification were performed using a mass spectrometer in selected reaction-monitoring mode with positive electrospray ionization. The lower limit of quantification was 5 ng/mL for all analytes with linear ranges up to 5000 ng/mL for caffeine and 1000 ng/mL for its metabolites. The coefficient of variation for assay precision was less than 12.6%, with an accuracy of 93.5-114%. The assay was successfully applied to determine plasma concentrations of caffeine, theobromine, paraxanthine, and theophylline in rat administered various energy drinks containing the same caffeine content. Various energy drinks exhibited considerable variability in the pharmacokinetic profiles of caffeine and its three primary metabolites, even containing the same caffeine. Different additives of energy drinks might contribute to these results.
- Food chemistry.Food Chem.2013 Dec 1;141(3):2735-42. doi: 10.1016/j.foodchem.2013.05.069. Epub 2013 May 24.
- A rapid, sensitive, simple and accurate LC-MS/MS method for the simultaneous quantitation of caffeine, and its three primary metabolites, theobromine, paraxanthine, and theophylline, in rat plasma was developed and validated. Chromatographic separation was performed on an Agilent Poroshell 120 EC-C1
- PMID 23871018
- 橋爪 秀一
- Journal of International Society of Life Information Science 28(1), 148-152, 2010-03-01
- ストレス指標として、唾液中のクロモグラニンA(CgA)及び瞳孔対光反応(瞳孔ストレス強度)を用いて、食品素材のストレス改善効果を検討した。それぞれの食品素材はデンプンペーストに混ぜ合わせた添加物として摂取した。その結果、CgAを指標とした場合に水との間で有意差(P<0.05)が得られたのは唐辛子の添加物であり、瞳孔ストレス強度で有意差(P<0.05)が得られたのはテオブロミン-リッチカ …
- NAID 110007612619
- Quantification of theobromine and caffeine in saliva, plasma and urine via liquid chromatography-tandem mass spectrometry : A single analytical protocol applicable to cocoa intervention studies
- PTOLEMY Adam S.,TZIOUMIS Emma,THOMKE Arjun,RIFAI Sami,KELLOGG Mark
- Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 878(3), 409-416, 2010-02-01
- NAID 10028032364
- 化合物和名 テオブロミン 化合物英名 Theobromine 骨 格 名 プリン 生合成経路 カカオ豆などに含まれるプリン誘導体。強心作用、腎血管の拡張、尿細管の再吸収抑制などで利尿効果を示す。利尿効果はテオフィリンより弱いが持続性が ...
- theo·bro·mine noun \ ˌ thē-ə-ˈ brō-ˌ mēn, -mən\ Definition of THEOBROMINE: a bitter alkaloid C 7 H 8 N 4 O 2 closely related to caffeine that occurs especially in cacao beans and has stimulant and diuretic properties Origin of THEOBROMINE
- 中枢作用 ：眠気消失、知的活動↑、興奮、不眠、振戦、神経過敏、けいれん、胃腸障害
- 心血管系作用 ：陽性変力作用、陽性変時作用
- cerntral nervous system stimulant, CNS stimulant
- 3,7-ジメチルキサンチン 3,7-dimethylxanthine