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Capillary electrophoretic determination of theanine, caffeine, and catechins in fresh tea leaves and oolong tea and their effects on rat neurosphere adhesion and migration.
J Agric Food Chem. 2003 Dec 03; 51(25):7495-503.JA

Abstract

Theanine, caffeine, and catechins in fresh tea leaves and oolong tea were determined by using capillary electrophoresis (CE). CE separated these tea polyphenols from three other tea ingredients, namely, caffeine, theophylline, and theanine, within 8 min. The young leaves (apical bud and the two youngest leaves) were found to be richer in caffeine, (-)-epigallocatechin gallate (EGCg), and (-)-epicatechin gallate (ECg) than old leaves (from 5th to 7th leaves). On the other hand, the old leaves (from 8th to 10th leaves) contained higher levels of theanine, (-)-epigallocatechin (EGC), and (-)-epicatechin (EC). Results from a comparison of fresh young tea and oolong tea compositions indicated oolong tea contained more theanine and catechins than fresh young tea. Furthermore, it was found that the levels of theanine, EGC, and EGCg in young leaves rose markedly with the withering process. Caffeine did not markedly change. However, fully or partially fermented teas (oolong tea or pauchong tea) have a common initial step in the withering process. Fresh tea leaves or oolong tea extract (0.1%, w/v) markedly inhibited neurosphere adhesion, cell migration, and neurite outgrowth in rat neurospheres. Theanine (348 micrograms/mL) and caffeine at high concentration (50 micrograms/mL) did not inhibit neurosphere adhesion or migration activities, but EGCg at 20 micrograms/mL effectively inhibited neurosphere adhesion for 24 h. These results indicated that EGCg might affect neural stem cell survival or differentiation.

Authors+Show Affiliations

Graduate Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Section 1, Jen-Ai Road, Taipei, Taiwan 100.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

14640605

Citation

Chen, Chia-Nan, et al. "Capillary Electrophoretic Determination of Theanine, Caffeine, and Catechins in Fresh Tea Leaves and Oolong Tea and Their Effects On Rat Neurosphere Adhesion and Migration." Journal of Agricultural and Food Chemistry, vol. 51, no. 25, 2003, pp. 7495-503.
Chen CN, Liang CM, Lai JR, et al. Capillary electrophoretic determination of theanine, caffeine, and catechins in fresh tea leaves and oolong tea and their effects on rat neurosphere adhesion and migration. J Agric Food Chem. 2003;51(25):7495-503.
Chen, C. N., Liang, C. M., Lai, J. R., Tsai, Y. J., Tsay, J. S., & Lin, J. K. (2003). Capillary electrophoretic determination of theanine, caffeine, and catechins in fresh tea leaves and oolong tea and their effects on rat neurosphere adhesion and migration. Journal of Agricultural and Food Chemistry, 51(25), 7495-503.
Chen CN, et al. Capillary Electrophoretic Determination of Theanine, Caffeine, and Catechins in Fresh Tea Leaves and Oolong Tea and Their Effects On Rat Neurosphere Adhesion and Migration. J Agric Food Chem. 2003 Dec 3;51(25):7495-503. PubMed PMID: 14640605.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Capillary electrophoretic determination of theanine, caffeine, and catechins in fresh tea leaves and oolong tea and their effects on rat neurosphere adhesion and migration. AU - Chen,Chia-Nan, AU - Liang,Chia-Min, AU - Lai,Jueng-Rong, AU - Tsai,Yao-Jen, AU - Tsay,Jyh-Shyan, AU - Lin,Jen-Kun, PY - 2003/12/3/pubmed PY - 2004/1/15/medline PY - 2003/12/3/entrez SP - 7495 EP - 503 JF - Journal of agricultural and food chemistry JO - J. Agric. Food Chem. VL - 51 IS - 25 N2 - Theanine, caffeine, and catechins in fresh tea leaves and oolong tea were determined by using capillary electrophoresis (CE). CE separated these tea polyphenols from three other tea ingredients, namely, caffeine, theophylline, and theanine, within 8 min. The young leaves (apical bud and the two youngest leaves) were found to be richer in caffeine, (-)-epigallocatechin gallate (EGCg), and (-)-epicatechin gallate (ECg) than old leaves (from 5th to 7th leaves). On the other hand, the old leaves (from 8th to 10th leaves) contained higher levels of theanine, (-)-epigallocatechin (EGC), and (-)-epicatechin (EC). Results from a comparison of fresh young tea and oolong tea compositions indicated oolong tea contained more theanine and catechins than fresh young tea. Furthermore, it was found that the levels of theanine, EGC, and EGCg in young leaves rose markedly with the withering process. Caffeine did not markedly change. However, fully or partially fermented teas (oolong tea or pauchong tea) have a common initial step in the withering process. Fresh tea leaves or oolong tea extract (0.1%, w/v) markedly inhibited neurosphere adhesion, cell migration, and neurite outgrowth in rat neurospheres. Theanine (348 micrograms/mL) and caffeine at high concentration (50 micrograms/mL) did not inhibit neurosphere adhesion or migration activities, but EGCg at 20 micrograms/mL effectively inhibited neurosphere adhesion for 24 h. These results indicated that EGCg might affect neural stem cell survival or differentiation. SN - 0021-8561 UR - https://www.unboundmedicine.com/medline/citation/14640605/Capillary_electrophoretic_determination_of_theanine_caffeine_and_catechins_in_fresh_tea_leaves_and_oolong_tea_and_their_effects_on_rat_neurosphere_adhesion_and_migration_ L2 - https://dx.doi.org/10.1021/jf034634b DB - PRIME DP - Unbound Medicine ER -