Abstract: Four different treatments including water-extracted process, pectase-extracted process, trypsin-extracted process and combined-enzyme-extracted process were respectively applied to extract tea polysaccharides (TPS) from Laoshan green tea in this article. The extract ratio of combined-enzyme process method reached 5.17±0.17 % and higher than those of the three other process methods. The crude TPS obtained from the four process methods were further purified through Sepharose FF and the main polysaccharides fraction was obtained respectively. Then comparisons on the components of monosaccharides, amino acids in the purified TPS were conducted. The four process methods had no influence on the kinds of monosaccharides in tea polysaccharides, but little on the proportion of the monosaccharisdes. The total sugar content of TPS prepared by the four process methods was decreased in following pectase-extracted process, combined-enzyme-extracted process, trypsin-extracted process, and water-extracted process. Especially, in pectase-extracted process it reached to 95.26±4.09%, while the uronic acids content decreased greatly. The four process methods had no influence on the kinds of amino acids in tea polysaccharides, but great on the proportion of them.

Key words: tea polysaccharides, enzyme-extracted process, components, monosaccharides, uronic acids, amino acids