Physiological effects of l-theanine and theogallin enriched decaffeinated green tea extract

Green tea is known to have stimulating properties which are believed to derive from caffeine. The present project was initiated to characterize a theanine and theogallin enriched decaffeinated extract of green tea in a beverage using electrophysiological parameters in vitro, in vivo (rat) and in humans (randomized trial in comparison to placebo). Oral administration of 2.5 grams of this extract led to statistically significant changes of physiological brain activity in volunteers. Already one hour after intake of the drink containing the extract basic delta activity of the quantitatively processed electroencepha…