两种常用膜对地龙匀浆液有效成分分级分离效果的比较

Comparation of separation of earthworm homogenate between two different membranes

目的明确两种常用膜聚偏氟乙烯(PVDF)及无机陶瓷膜对地龙匀浆液中有效成分分级分离效果的优劣,从而选择理想的膜分离材料。方法在最优分离操作条件下,分别用截留分子量(MWCO)为100 0005、0 0001、0 000的PVDF滤过膜及0.2μm Al2O3、50 nm ZrO2无机陶瓷膜管对地龙匀浆液分级分离,留取截留液和滤过液,采用考马斯亮蓝法通过紫外分光光度计测定蛋白含量、SDS-PAGE测定蛋白分子量的分布、纤维蛋白平板法测定纤溶活性。结果 PVDF分级分离地龙匀浆液,有效成分截留率高,蛋白损失率小;SDS-PAGE显示活性蛋白成分分子量在10 000～100 000之间,有纤溶活性的成分分子量在10 000～50 000,用50 000膜分离时能得纤溶活性高的液体,提纯分离效果好。结论 PVDF对地龙匀浆液分离效果优于无机陶瓷膜。

AIM To choose the suitable membrane material between PVDF and inorganic ceramic membrane according to the separating effects of earthworm homogenate.METHODS Under the optimal conditions,earthworm homogenates were separated through PVDF membranes with the molecular weights cut-off（MWCO） of 100 000、50 000、10 000,respectively,and through inorganic ceramic membranes with materials of Al2O3 and ZrO2 and the pore size of 0.2 μm and 50 nm,respectively.All residual liquid and percolate were reserved.Their protein contents were determined by Bradford method,distribution of protein molecular weight by SDS-PAGE,and fibrinolytic activity by fibrin plate method.RESULTS Experiments showed that PVDF had more separating advantages than inorganic ceramic membrane.With good entrapping rate and less loss of protein.The distribution of molecule weight was in the range of 10 000-100 000 active protein for and 10 000-50 000 MW for fibrinolytic activity,and 50 000 MWCO PVDF had the higher separation effect on fibrinolytic activity.CONCLUSION The PVDF is superior to the inorganic ceramic membrane in separation of the earthworm homogenate.