ABSTRACT
Tea (Camellia sinensis, Figure 8.1) has been discovered and utilized for its unique avor and medicinal properties by man for a long time, which may be traced back to the Shen Nong era in ancient China, around 5000-6000 years ago (Chen, 2002). Although the tea plant grows in many countries, general consensus attributes the birth of the tea plant to the mountainous area of today’s southwestern China (Hara, 2001). While Chinese legend tells how Sheng Nong found the antidote and healing power of tea, the rst documented effects of tea were in the book Ben Cao Jing (本 草经 Materia Medica), which was written during the era of the Han Dynasty (206
8.1 Introduction .................................................................................................. 173 8.2 Green Tea Catechins and their Antioxidative Activities .............................. 175
8.2.1 Major Types of Green Tea Catechins ............................................... 175 8.2.2 Antioxidative Activity of Tea Catechins .......................................... 177
8.3 Green Tea Antioxidants and Health Bene ts ............................................... 178 8.3.1 Results from Studies Using Cell Lines ............................................. 179
8.3.1.1 Green Tea and Neurodegenerative Diseases ...................... 179 8.3.1.2 Green Tea and Obesity ....................................................... 181 8.3.1.3 Green Tea and Cardiovascular Disease ............................. 181 8.3.1.4 Green Tea and Cancer ........................................................ 181
8.3.2 Results from Studies through Animal Models and Clinical Trials ................................................................................... 182
8.3.2.1 Green Tea and Cancer ........................................................ 182 8.3.2.2 Green Tea and Cardiovascular Diseases ............................ 184 8.3.2.3 Green Tea, Obesity, and Diabetes ...................................... 185
8.4 Stability and Chemical Changes of Green Tea Catechins during Food Processing ................................................................................ 185
8.5 Functional Foods Containing Green Tea or Green Tea Antioxidants .................................................................................................. 188 8.6 Conclusions ................................................................................................... 190 References .............................................................................................................. 190
bc-ad 220). A comprehensive book on tea by Cha Jing (茶经 The Classics of Tea) was published in ad 780 by Yu Lu of Tang Dynasty, which described in detail the botany, cultivation, processing, quality, and preparation of tea, as well as proper methods and style of drinking tea including utensils and water quality (Chen, 2002; Hara, 2001).
