Occurrence, Biosynthesis and Metabolism of Theanine (γ-Glutamyl-L-ethylamide) in Plants: A Comprehensive Review

  title={Occurrence, Biosynthesis and Metabolism of Theanine ($\gamma$-Glutamyl-L-ethylamide) in Plants: A Comprehensive Review},
  author={Hiroshi Ashihara},
  journal={Natural Product Communications},
  • H. Ashihara
  • Published 1 May 2015
  • Environmental Science
  • Natural Product Communications
Theanine (γ-glutamyl-L-ethylamide) is the most abundant non-protein amino acid in tea leaves. In addition to Camellia sinensis, theanine occurs in several plants belonging to the Ericales. Biosynthesis of theanine from glutamic acid and ethylamine by theanine synthetase is present in all organs of tea seedlings, but roots are the major site of theanine biosynthesis in adult tea trees. Theanine is transported from roots to young leaves via the xylem sap. Theanine is hydrolysed to glutamic acid… 

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