Roots of Hydroponically Grown Tea (Camellia sinensis) Plants as a Source of a Unique Amino Acid, Theanine

Abstract

The beneficial effects of green tea are well documented. However, most research has\rreported the effects of green tea brewed solely from leaves or leaf extracts. We focused on\rtea roots and developed a hydroponic system to explore the effect on roots that\rbiosynthesize one of the rarest functional amino acids, theanine. The level of theanine in\rtea roots was much higher than in leaves, which was analyzed using HPLC. Moreover, a\rhigher level of theanine was detected in white rootlets than in lignified roots. Thus, tea\rroots cultured hydroponically in a controlled environment might be considered a natural\rdrug containing theanine, which could lead to synergistic effects with other ingredients of\rthe root. This novel medicinal material from the roots demonstrates a significant medical\rfunction for tea that extends beyond its leaves.\r