Composition and bioactivity of polysaccharides from tea seeds obtained by water extraction

In this paper, the composition and biological activities of polysaccharides from tea seed (TSPS) obtained by water extraction were investigated. The properties and chemical compositions of TSPS were analyzed with HPGPC, IC, and IR methods. The results showed that TSPS consisted of three kinds of polysaccharides with the molecular weight of 500 kDa, 130 kDa, and 5 kDa. TSPS consisted of rhamnose, xylose, arabinose, glucose and galactose, GalA, GulA, with a molar ratio of 4.9:1.7:11.1:27.2:14.0:3.4:1, sugar backbone of TSPS might consist of glucose, but branched chain may consist of rhamnose, xylose, arabinose, and galactose. The IR spectrum of TSPS revealed the typical characteristics of polysaccharides and protein. TSPS significantly inhibited the growth of K562 cells, especially, at the concentration of 50 μg/ml; the inhibition activity of TSPS was the highest with an inhibition ratio beyond 38.44±2.22% (P<0.01). TSPS with high concentrations (100, 200 and 400 μg/ml) had higher proliferation effect on lymphocyte. Results of these studies demonstrated that the polysaccharide had a potential application as natural antitumor drugs.