J. Technology and Education, Vol.13, No.1, pp.1-7, 2006
研究論文
茶カテキンの抗酸化作用に関する研究
 
芳野恭士*、渭原 寛、木村志帆、杉浦由佳
沼津工業高等専門学校 物質工学科(〒410-8501 沼津市大岡3600
*k-yoshino@numazu-ct.ac.jp
 
Antioxidant Effects of Tea Catechins
 
Kyoji YOSHINO, Hiroshi IHARA, Shiho KIMURA, Yuka SUGIURA
Numazu College of Technology (3600 Ooka, Numazu, Shizuoka 410-8501, Japan)
 
(Received April 28, 2006; Accepted May 17, 2006)
 
Abstract
The antioxidant activities of green tea catechins, (-)-epicatechin (EC) and (-)-epigallocatechin gallate (EGCG), were compared in vitro and in the plasma of mice. In the peroxidations of mouse plasma in vitro, the scavenging ability of EGCG against alkoxy radicals generated by t-butyl hydroperoxide were stronger than that of EC, though the ability of EC against peroxy radicals generated by 2,2’-azobis(2-amidinopropane) dihydrochloride was similar to that of EGCG. Oral administration of EC and EGCG at a dose of 100 mg/kg body weight increased antioxidant activities based on the scavenging abilities against both kinds of radicals as well as the chelating ability against iron in the plasma of 5 week-old male ICR mice 1 hr after treatment. The antioxidant activities based on the scavenging ability against peroxy radicals in the plasma of mice administered EC tended to be higher than those administered EGCG, while the activities based on the chelating ability against iron in the plasma of mice administered with EGCG tended to be higher than those administered EC. The antioxidant activities based on the scavenging ability against alkoxy radicals in the plasma of mice administered EC and EGCG were almost the same. These results suggest that the antioxidant activities associated with the administration of catechins in mice do not necessarily accurately reflect the process in vitro and that activities may be influenced by the absorption, stability, and metabolism of catechin in mice.

Keywords:
Tea, Catechin, Antioxidant, Mouse