5种枣果实中凝集素的提取及生物活性分析

提取5种枣果实(壶瓶枣、骏枣、黄河滩枣、黑叶子枣、大白铃枣)的凝集素,经硫酸铵沉淀、透析,得到蛋白质提取液,用不同类型的人血细胞(O型、A型、B型、AB型)检测其凝集活性。通过凝集活性和热稳定性实验比较5种枣果实凝集素的生物活性。结果表明:各个品种的枣果实的凝集素对不同血型均有不同程度的凝集效果,如壶瓶枣、黄河滩枣和大白铃枣对A型血的凝集效价都可以达到27,而骏枣和黑叶子枣略有差异,分别达到25和26,黄河滩枣、黑叶子枣和大白铃枣对B型血的凝集效价可以达到27,骏枣和壶瓶枣略有差异,分别达到25和26;5种枣果实凝集素均能耐70℃高温,在80℃以后均失去凝集活性;5种枣均无单糖和寡糖的专一结合位点,而且5种枣果凝集素活性的维持与金属离子Mg2+、K+、Cu2+、Fe3+的关系不大。

Extraction and Biological Activity Analysis of Lectin from Five Cultivars of Chinese Jujube

Lectin from 5 cultivars of Chinese jujube was isolated by ammonium precipitation and dialysis.Its ability to induce blood cell aggregation was then evaluated using different blood types(A,B and O).The results obtained showed that lectin from different cultivars of Chinese jujube had different aggregation-inducing activities for different blood types.For example,the blood cell aggregation valence to blood type A of lectin from Chinese jujube cultivars Huping,HuangHetan and Dabailing reached 27compared with 25and 26for lectin from Chinese jujube cultivars Jun and Huping dates,respectively.Lectin from five different Chinese jujube cultivars were all stable at 70 ℃.However,when the temperature reached 80 ℃,all of them lose aggregation-inducing ability.Moreover,they had no monosaccharide and oligosaccharide specific binding sites.The metal ions Mg2+,K+,Cu2+and Fe3+ were not essential for its blood cell aggregation activity.