L-Theanine an Astounding Amino Acid in Tea, Its Synthesis and Health Benefits: A Review

Urmi Saha *

Tea Board India, Kolkata, 700001, India.

Palak Gupta

Tea Board India, Kolkata, 700001, India.

Mohipal Singh

Tea Board India, Kolkata, 700001, India.

*Author to whom correspondence should be addressed.


Tea being a traditional beverage has been consumed for thousands of years becoming a daily habit that facilitates healthy living. Both black and green tea drinking have historically and generally been linked to feelings of refreshment and relaxation. Tea's L-Theanine (L-ʀ- glutamylethylamide), a non-protein amino acid primarily found in tea leaves, is thought to be responsible for this consequence. In addition to improving tea’s flavour, L-Theanine has numerous health benefits. It has a major effect on diseases linked to lifestyle, such as improving vascular function and decreasing risk of cardiovascular diseases. It also has anti- hypertensive, stress reduction, and cancer suppression activity. This amino acid can mitigate the negative effects of neurotoxins, promote normal sleep patterns, and enhance memory.

This review paper aims to explain the chemical and physical properties of L-Theanine, as well as current methods for its synthesis and extraction. It also discusses the factors that influence the theanine content of tea plants and potential health benefits that it could have for humans.

Keywords: Tea, thianine, amino acid, theanine properties, tea plants, health benefits

How to Cite

Saha , Urmi, Palak Gupta, and Mohipal Singh. 2024. “L-Theanine an Astounding Amino Acid in Tea, Its Synthesis and Health Benefits: A Review”. International Journal of Biochemistry Research & Review 33 (2):21-32. https://doi.org/10.9734/ijbcrr/2024/v33i2855.


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