Theanine
L-Theanine | |
| Clinical data | |
|---|---|
| Other names | γ-L-Glutamylethylamide |
| Dependence liability | None |
| Routes of administration | Oral |
| ATC code |
|
| Legal status | |
| Legal status |
|
| Pharmacokinetic data | |
| Onset of action | ~1 hour[1] |
| Elimination half-life | Capsule: ~1.2 hours Green Tea: ~0.8 hours[1] |
| Identifiers | |
IUPAC name
| |
| CAS Number | |
| PubChem CID | |
| DrugBank | |
| ChemSpider | |
| UNII | |
| KEGG | |
| ChEBI | |
| ChEMBL | |
| CompTox Dashboard (EPA) | |
| ECHA InfoCard | 100.019.436 |
| Chemical and physical data | |
| Formula | C7H14N2O3 |
| Molar mass | 174.200 g·mol−1 |
| 3D model (JSmol) | |
| Melting point | 174.20 °C (345.56 °F) [3] |
| Boiling point | 215 °C (419 °F) [3] |
SMILES
| |
InChI
| |
Theanine /ˈθiːəniːn/, also known as L-theanine, L-gamma-glutamylethylamide, or N5-ethyl-L-glutamine, is a non-proteinogenic amino acid similar to the proteinogenic amino acids L-glutamate and L-glutamine. It is produced by certain plants such as the tea plant (Camellia sinensis), and by some fungi.[3][4] Theanine was discovered in 1949 as a constituent of green tea and was isolated in 1950 from gyokuro tea leaves.[5] It constitutes about 1–2% of the dry weight of green tea leaves.[4]
The name theanine usually refers to the enantiomer L-theanine, which is the form found in tea leaves from which it is extracted as a powder.[4][6] The right-handed enantiomer, D-theanine, is less-studied.
Theanine is sold as a dietary supplement.[4] It is packaged in gelatin capsules, tablets, and as a powder, and may be an ingredient in branded supplements with caffeine. It is also used as an ingredient in food and beverages. In 1964 Japan approved its unlimited use in all foods (including chocolates, soft drinks, and herb teas) except infant food,[4][7] while since 2007 it is considered to be safe at doses up to 250 milligrams (mg) per serving by the US Food and Drug Administration.[8]
In 2011 the European Food Safety Authority found there was insufficient evidence for a causal relationship between theanine consumption and improved cognitive function, alleviation of psychological stress, maintenance of normal sleep, or reduction of menstrual discomfort.[9]
- ^ a b Scheid L, Ellinger S, Alteheld B, Herholz H, Ellinger J, Henn T, et al. (December 2012). "Kinetics of L-theanine uptake and metabolism in healthy participants are comparable after ingestion of L-theanine via capsules and green tea". The Journal of Nutrition. 142 (12): 2091–2096. doi:10.3945/jn.112.166371. PMID 23096008.
- ^ Cite error: The named reference
RSC_Chemspiderwas invoked but never defined (see the help page). - ^ a b c "L-Theanine". PubChem, US National Library of Medicine. 13 May 2023. Retrieved 16 May 2023.
- ^ a b c d e "L-Theanine". Drugs.com. 20 February 2023. Retrieved 16 May 2023.
- ^ "Components of Gyokuro｜ IPPODO". Ippodo-tea.co.jp. Archived from the original on 2015-12-23. Retrieved 2015-05-07.
- ^ Schuster J, Mitchell ES (March 2019). "More than just caffeine: psychopharmacology of methylxanthine interactions with plant-derived phytochemicals". Progress in Neuro-Psychopharmacology & Biological Psychiatry. 89: 263–274. doi:10.1016/j.pnpbp.2018.09.005. PMID 30213684. S2CID 52274913.
- ^ "The Japan Food Chemical Research Foundation". www.ffcr.or.jp. Retrieved 2025-03-29.
- ^ "GRAS notice for L-theanine". US Food and Drug Administration. 5 February 2007. Retrieved 1 May 2023.
- ^ EFSA Panel on Dietetic Products, Nutrition and Allergies, European Food Safety Authority (2011). "Scientific Opinion on the substantiation of health claims related to L-theanine from Camellia sinensis (L.) Kuntze (Tea) and improvement of cognitive function (ID 1104, 1222, 1600, 1601, 1707, 1935, 2004, 2005), alleviation of psychological stress (ID 1598, 1601), maintenance of normal sleep (ID 1222, 1737, 2004) and reduction of menstrual discomfort (ID 1599) pursuant to Article 13(1) of Regulation (EC) No 1924/2006". EFSA Journal. 9 (6): 2238. doi:10.2903/j.efsa.2011.2238.