top Clinical Studies Tea polysaccharides have an important role in preventing degenerative diseases such as cardiovascular disease and diabetes type II. Many of the pharmacological action of tea are related to the polyphenol and polysaccharide fractions of tea.
They have anti-coagulant properties and reduce platelet stickiness, are anti-thrombotic and reduce blood lipids. They may help to raise HDL cholesterol and lower LDL cholesterol. They modulate the body's immune function by T- and B-lymphocyte activation, and promote interferon, white cell medium and tumor necrosis factor. Tea polysaccharides help to lower blood pressure, increase coronary artery capacity, lower blood sugar and improve beta cell function of the pancreas, and may thus have anti-diabetic properties. They have anti-radiation properties, they help to eliminate free radicals, improve blood reproduction and maintenance and have anti-viral activity. Tea polysaccharides also contain the monosaccharides ribose, xylose, glucose, galactose and arabinose.
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Published Clinical Studiesclin
Composition, characteristic and activity of rare earth element-bound polysaccharide from tea.1
Wang D, Wang C, Zhao G, Wei Z, Tao Y, Liang X.
Key Laboratory of Tea Biotechnology, Agricultural Ministry, the People's Republic of China, Anhui Agricultural University, Hefei. mailwangdf@163.net
The compositions and structural characteristics of rare earth elements-bound polysaccharides from tea (REE-TPS) were studied with the methods of Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Gas Chromatography (GC) and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. The results show that polysaccharide from tea (TPS) was a sort of glycoprotein and coordinated with Rare Earth Elements (REE) closely. The sugar fraction was composed of Rha, Ara, Xyl, Fuc, Glc, and Gal. There existed almost all natural amino acids with Glx, Asx, and Hyp as the major parts in the protein fraction. The REEs in REE-TPS were mainly composed of La, Ce, and Nd, especially, more than 75% of them was La. The coordination atom of the first coordination shell of La in REE-TPS was oxygen, the coordination number of which was 6, and the average distance between the atoms was 2.52 A. The second shell was formed from sulfur atoms, the coordination number and the average distance were 3 and 2.91 A, respectively. The bio-experiments show that REE-TPS could decrease the content of blood glucose in mice significantly.
PMID: 11676010 [PubMed - indexed for MEDLINE]
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[Chemical properties and scavenging effects on active oxygen radicals of tea polysaccharides]2
Chen H, Xie B.
Food Science Department of Huazhong, Agricultural University, Wuhan 430070, China.
The chemical composition and scavenging effects of a kind of glycoprotein from tea on active oxygen free radicals were studied. The tea polysaccharides(TPS) were composed of arabinose, ribose, xylose, glucose and galactose. TPS(8.5-170 mg/L) could scavenge the .OH produced in deoxyribose-Fe2+ reaction and the scavenging rate was between 5.5% to 74.7%.
PMID: 11255768 [PubMed - indexed for MEDLINE]
Quantification of uronic acids in tea polysaccharide conjugates and their antioxidant properties.3
Chen H, Zhang M, Xie B.
Department of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
A technique of high-performance liquid chromatography (HPLC) was described for the measurement of total uronic acids in tea polysaccharide conjugates. This method was applied to polysaccharide conjugate extracts obtained from green tea after most of the components that produce interference were removed. The preliminary extraction process was according to the procedure of isolation of polysaccharide conjugates. The uronic acid content of different polysaccharide conjugate fractions was quantified by HPLC on a Sugar-Pak I column with a 1.0 x 10(-)(4) mol x L(-)(1) calcium disodium ethylenediaminetetraacetic acid solution as the mobile phase and refractive index detection. The validation study showed high recoveries (>97.0%) and low coefficients of variance (<3.0%). The minimum detectable limit concentration of uronic acid was 10 microg x mL(-)(1). The analysis of a standard range of galacturonic acid concentrations (100-4000 microg x mL(-)(1)) yielded linear results. The use of the method on different polysaccharide conjugate fraction samples confirmed its effectiveness. With the high content of uronic acids in polysaccharide conjugates, the stronger reactive oxygen species scavenging activities were found.
PMID: 15161193 [PubMed - indexed for MEDLINE]
Inhibition of tumour growth and inflammation by consumption of tea.4
Das M, Sur P, Gomes A, Vedasiromoni JR, Ganguly DK.
Division of Pharmacology and Experimental Therapeutics, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Calcutta 700 032, India.
The antitumour effect of tea was evaluated in the 3-methylcholanthrene (3-MC) induced solid tumour model in mice. Both black and green tea inhibited tumour growth and prevented metastasis. Histopathological study showed that tea treatment was able to reduce malignancy. Superoxide dismutase (SOD), a free radical scavenger, was found to be significantly increased in the serum of mice administered tea. Moreover, tea extracts were able to reduce the level of thiobarbituric acid reactive substance (TBARS) in the sera of mice. Tea extracts (both black and green) also showed antiinflammatory activity in the carrageenan-induced paw oedema model in the rat. Copyright 2002 John Wiley & Sons, Ltd.
PMID: 11933138 [PubMed - indexed for MEDLINE]
Components and activity of polysaccharides from coarse tea.5
Wang Dongfeng W, Wang Chenghong W, Li Jun L, Zhao Guiwen Z.
Key Laboratory of Tea Biotechnology, Agricultural Ministry of the People's Republic of China, Hefei 230036, People's Republic of China.
Coarse tea contained a high content of polysaccharide complex. Composed of polysaccharide and protein, the polysaccharide complex from tea (TPS) belonged to glycoprotein with the molecular weight () of (10.7-11.0) x 10(4). When mice (7 weeks old, C57BL/8) were injected with TPS, the levels of blood glucose (BG) in normal mice and model mice with high BG were decreased significantly by averages of 13.54 and 22.18%, respectively. The antibody concentration (OD(413 nm)) in the mice injected with 2.4 mg/mL TPS was increased evidently by 44.93% (p < 0.01). TPS treatment was beneficial not only for the subsequent production of interleukin (IL) 2 in spleen cells of adjuvant arthritis (AA) rats but also because it prohibited the body from producing too much IL-1 in AA rats. Treatment of diabetes with coarse tea in both China and Japan may be related to TPS and the content of TPS in coarse tea.
PMID: 11170619 [PubMed - indexed for MEDLINE]