不同酶法提取工艺对茶多糖组成的影响

采用果胶酶、胰蛋白酶以及复合酶等3种提取法和不加酶水浸提法为对照,提取崂山粗老绿茶中的茶多糖(TPS)。结果表明,复合酶提取法的提取率最高,达到5.17±0.17%。对4种工艺获得的TPS用SepharoseFF阴离子交换柱进行分离纯化,收集主要的含糖组分,分别测定其多糖含量、单糖组成、氨基酸组成。结果表明4种工艺对提取的TPS的单糖组成种类影响不大,但对各单糖组分之间的比例稍有影响。4种工艺获得的TPS的总糖含量由高到低依次为果胶酶法、复合酶法、胰蛋白酶法以及不加酶水浸提法,其中果胶酶法获得的TPS总糖含量高达95.26±4.09%,但其糖醛酸含量比其他3种工艺显著降低。4种工艺对提取的TPS的氨基酸组成种类影响亦不大,但对各氨基酸的含量有较大的影响。果胶酶法、胰蛋白酶法提取的TPS的各氨基酸含量与不加酶水浸提法的相比有较大的减少。

Effects of Different Extraction Processes on the Components of Tea Polysaccharides

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.