L-Theanine CAS NO.3081-61-6

Theanine is a characteristic amino acid in tea. It is synthesized in the roots of the tea plant from glutamic acid and ethylamine under the action of theanine synthase. It is a crucial substance contributing to the flavor of tea, primarily characterized by its umami and sweetness, and is a major component of the teas stimulating and sweetening properties. Twenty-six amino acids (6 non-protein amino acids) have been identified in tea, generally accounting for 1% to 5% of the dry weight of tea leaves. Theanine accounts for more than 50% of the total free amino acids in tea.

Tea plant amino acids refer to all 26 amino acids contained in tea leaves. Of these, 20 are related to protein synthesis and are called protein amino acids; the remaining 6 are not related to protein synthesis and are called non-protein amino acids. These 6 are the most important in tea, and the most important of these is theanine. Therefore, theanine is considered a characteristic amino acid of tea. As the most abundant characteristic non-protein amino acid in tea, theanine is safe and has no toxic side effects. It possesses various biological activities, including antioxidant, immune-regulating, anti-aging, and antagonistic effects against the cell excitatory toxicity caused by excessive glutamic acid. Meanwhile, L-theanine, as an alkylamine, can activate γ-T immune cells, promote cell proliferation and cytokine secretion, enhance the bodys ability to resist tumor cells, and reduce the infection of external microorganisms, thus lowering the bodys chances of catching colds and influenza.

Introduction: Theanine is an amino acid found only in tea leaves, with the highest content in tea. L-theanine is synthesized in the roots of the tea plant and transported to the leaves through the branches, accumulating in the leaves. Under sunlight, theanine is converted into catechins. Therefore, L-theanine content is higher in high-grade green tea grown in shaded environments, while it is lower in ordinary coarse tea leaves, where polyphenol content is higher.

Chemical Properties: White crystalline powder. Odorless, with a slightly sweet, characteristic taste; taste threshold 0.15%. Decomposition temperature 214–215℃. Soluble in water, insoluble in ethanol and ether. Naturally occurring L-theanine is abundant in high-quality green tea (up to 2.2%). Uses: Seasoning. Mainly used in green tea; dosage not specified. Nutritional fortifier.

Uses: A flavoring agent (the aroma component of green tea), dosage not specified.

Uses: Used as a food additive. Its sedative effect when added to food, flavor-improving effect of L-theanine, immune enhancement, blood pressure reduction, brain function improvement, promoting brain learning and memory, and effectively enhancing liver detoxification. Theanines blood pressure-lowering effect. A glutamine analog, also a component of green tea. It can bind to AMPA, potassium magnesium sulfate, and NMDA glycine receptors in rat cortical neurons, but its affinity is lower than that of glutamate. It has been studied as a glutamate transport inhibitor, preventing glutamate uptake in M5076 ovarian sarcoma-bearing mouse cells and increasing the effect of doxorubicin on tumor growth in M5076 mice.