Tea (Camellia sinensis) is a widely used plant for ethnopharmacological use mainly due to the presence of bioactive components such as phenolic compounds (gallic acid, p-coumaric acid and caffeic acid), purine alkaloids (theobromine, caffeine and theophylline), anthocyanins, flavonol glycosides (kaempferol, myricetin and quercetin), flavonoids (catechins).

The color varieties are mainly due to differences in treatment, climate, but basically the variations between plants are few.

It is grown in:

• India
• Cina
• Sri Lanka
• Kenya
• Indonesia

The most common are:

• black
• green
• oolong
• red

The characteristic scent of tea seems to be influenced by the jasmonic acid present in the leaves (1).

When tea is taken to prevent or combat disease, attention should be paid to doses and, as with almost all herbs, ingestion of large amounts may be toxic. When the tea is taken for therapeutic purposes for cardiovascular diseases, diabetes and more, the best results are obtained in people who consume 3-4 cups of tea (600-900 mg of catechins) per day (2).

This study believes that green tea plays a neuroprotective role in neurodegenerative diseases and memory decline with old age, such as Alzheimer's disease (3).

A polysaccharide composed only of glucose has been isolated from the green lemon and the authors of the discovery explain how this polysaccharide can be a potential therapeutic agent on prostate cancer (4).

Oral administration of green tea extract exercised cardioprotective activity and prevented  doxorubicin induced cardiotoxicity by accelerating heart antioxidant defense mechanisms and down regulating the lipid peroxidation levels to the normal levels (5).

The protective effect against hematologic neoplasms, especially acute myeloid leukemias has been suggested (6).

Green tea studies

References_________________________________________________

(1) Influence of Chloroplast Defects on Formation of Jasmonic Acid and Characteristic Aroma Compounds in Tea (Camellia sinensis) Leaves Exposed to Postharvest Stresses.  Li J, Zeng L, Liao Y, Gu D, Tang J, Yang Z.  Int J Mol Sci. 2019 Feb 27;20(5). pii: E1044. doi: 10.3390/ijms20051044.

(2) Studies on the Prevention of Cancer and Cardiometabolic Diseases by Tea: Issues on Mechanisms, Effective Doses, and Toxicities.  Yang CS, Zhang J. J Agric Food Chem. 2019 May 15;67(19):5446-5456. doi: 10.1021/acs.jafc.8b05242.

(3) Green tea supplementation produces better neuroprotective effects than red and black tea in Alzheimer-like rat model.  Schimidt HL, Garcia A, Martins A, Mello-Carpes PB, Carpes FP.  Food Res Int. 2017 Oct;100(Pt 1):442-448. doi: 10.1016/j.foodres.2017.07.026.

(4) Anti-tumor activity and the mechanism of a green tea (Camellia sinensis) polysaccharide on prostate cancer.  Yang K, Gao ZY, Li TQ, Song W, Xiao W, Zheng J, Chen H, Chen GH, Zou HY.  Int J Biol Macromol. 2019 Feb 1;122:95-103. doi: 10.1016/j.ijbiomac.2018.10.101.

(5) Cardioprotective effect of green tea extract on doxorubicin-induced cardiotoxicity in rats. Khan G, Haque SE, Anwer T, Ahsan MN, Safhi MM, Alam MF.  Acta Pol Pharm. 2014 Sep-Oct;71(5):861-8.

(6) Green tea consumption and risk of hematologic neoplasms: the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study).  Takada M, Yamagishi K, Iso H, Tamakoshi A.  Cancer Causes Control. 2019 Aug 26. doi: 10.1007/s10552-019-01220-z.