Determination of Conjugated Caffeine in Tea by Low-pH Precipitation Method

SONG Shuang; HUANG Ye-wei; WANG Xuan-jun; YU Hai-shuang; FANG Chong-ye; SHENG Jun; HAO Shu-mei

doi:10.13305/j.cnki.jts.2013.04.005

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Journal of Tea Science ›› 2013, Vol. 33 ›› Issue (4) : 322-326. DOI: 10.13305/j.cnki.jts.2013.04.005

Determination of Conjugated Caffeine in Tea by Low-pH Precipitation Method

SONG Shuang^1,2,3, HUANG Ye-wei^1,2,3, WANG Xuan-jun^2,3, YU Hai-shuang^2,3, FANG Chong-ye^2,3, SHENG Jun^2,3,*, HAO Shu-mei^4,*

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Abstract

The feasibility and superiority in the determination of conjugated caffeine in tea by the method of low-pH precipitation was investigated in order to provide some theories for the determination of caffeine content in tea accurately. The aqueous extract of green tea, black tea and fermented Pu-erh tea were selected as test samples. The content of conjugated caffeine of the tea samples was determined by the method of low-pH precipitation. Meanwhile, the results of conjugated caffeine content were verified by the method of chloroform-extraction. The results showed as follows: Low-pH precipitation method is suitable for the determination of conjugated caffeine in tea. The content of conjugated caffeine in fermented Pu-erh tea is the highest (2.59%) among the three tea samples. However, the contents of conjugated caffeine in the green tea and black tea were relatively low (0.04% and 0.07% respectively).

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conjugate-caffeine / low-pH precipitation / tea

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SONG Shuang, HUANG Ye-wei, WANG Xuan-jun, YU Hai-shuang, FANG Chong-ye, SHENG Jun, HAO Shu-mei. Determination of Conjugated Caffeine in Tea by Low-pH Precipitation Method[J]. Journal of Tea Science. 2013, 33(4): 322-326 https://doi.org/10.13305/j.cnki.jts.2013.04.005

References

[1] 陈宗懋. 中国茶经[M]. 上海: 上海文化出版社, 2005: 1-10.
[2] 赵卉, 杜晓. 低咖啡碱茶的研究进展[J]. 华中农业大学学报, 2008, 27(4): 564-568.
[3] 吴命燕, 范方媛, 梁月荣, 等. 咖啡碱的生理功能及其作用机制[J]. 茶叶科学, 2010, 30(4): 235-242.
[4] Paré W.The effect of caffeine and seconal on a visual discrimination task[J]. Journal of Comparative and Physiological Psychology, 1961, 54(5): 506-509.
[5] João M N Duarte, Paula M Agostinho, Rui A Carvalho, et al. Caffeine Consumption Prevents Diabetes-Induced Memory Impairment and Synaptotoxicity in the Hippocampus of NONcZNO10/LTJ Mice [J]. PLoS One, 2012, 7(4): 1-10.
[6] Huang YW, Liu Y, Dushenkov S.Anti-obesity effects of epigallocatechin-3-gallate, orange peel extract, black tea extract, caffeine and their combinations in a mouse model[J]. Journal of Functional Foods, 2009, 1(3): 304-310.
[7] Van Dam RM.Coffee and type 2 diabetes: From beans to beta-cells[J]. Nutrition, Metabolism and Cardiovascular Diseases, 2006, 16(1): 69-77.
[8] 易超然, 卫中庆, 邓湘蕾. 咖啡因改善糖尿病大鼠膀胱功能的观察[J]. 中国糖尿病杂志, 2006, 14(2): 144-145.
[9] Bairam A, Montandon G, Joseph V, et al. Enhancement of the breathing frequency response to hypoxia by neonatal caffeine treatment in adult male rats: The role of testosterone[J]. Respiratory Physiology & Neurobiology, 2009, 165(2/3): 261-265.
[10] Rapuri PB, Gallagher JC, Kinyamu HK, et al. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes[J]. American Journal of Clinical Nutrition, 2001, 74(5): 694-700.
[11] Grosso LM, Bracken MB.Caffeine metabolism, genetics, and perinatal outcomes: A review of exposure assessment considerations during pregnancy[J]. Annals of Epidemiology, 2005, 15(6): 460-466.
[12] Duarte PM, Marques MR, Bezerra JP, et al. The effects of caffeine administration on the early stage of bone healing and bone density[J]. Archives of Oral Biology, 2009, 54(8): 717-722.
[13] 宁井铭, 张正竹, 谷勋刚, 等. 云南晒青毛茶HPLC指纹图谱的研究[J]. 食品与发酵工业, 2009, 35(9): 36-40.
[14] 胡熙恩, 戴为智, 王学军, 等. 氯仿萃取咖啡因过程研究[J]. 清华大学学报: 自然科学版, 1995, 35(3): 13-19.
[15] 宛晓春. 茶叶生物化学[M]. 北京: 中国农业出版社, 2003.
[16] 杨红, 汪志君, 张凌云. 茶饮料冷后浑机理研究进展[J]. 福建茶叶, 2005, 1:12-15.
[17] 杨红, 汪志君, 张凌云. 茶饮料冷后浑的解决途径探讨[J]. 现代食品科技, 2006, 22(2): 243-246.
[18] 苗爱清, 伍锡岳, 庞式. 茶饮料沉淀的成因及解决措施[J]. 广东农业科学, 2001(3): 13-15.
[19] Y Hou, Wf Shao, Rong Xiao, et al. Pu-erh tea aqueous extracts lower atherosclerotic risk factors in a rat hyperlipidemia mode[J]. Experimental Gerontology, 2009, 44: 434-439.