枯草杆菌重组水蛭素的分离纯化工艺研究（摘要）

目的]优化枯草杆菌重组水蛭素的分离纯化工艺。方法]通过系列预处理和初步层析和精细纯化试验。发酵液固液分离和预处理：大批的发酵液采用连续流离心,取上清液,滴加50%三氯乙酸,当pH值达到2.2～2.5时停止滴加,静置1 h,离心,取上清液,用饱和NaOH调pH值回中性。然后利用SYNDER-UF202型超滤装置进行超滤浓缩脱盐,先用孔径为0.1μm的滤膜芯进行微滤除大固粒,再用截留分子量为1 000 Da的超滤膜芯进行超滤浓缩,加蒸馏水重复超滤浓缩脱盐。然后在等电点pH 4.0左右进行6倍体积的乙醇沉淀浓缩。离子交换初步层析：最佳pH值8.0,以Tris-HCl缓冲体系为佳;强阴离子交换选用Q Sepharose F.F.介质;系统电导率6 ms/cm,水蛭素的最大上样量以每毫升介质240 ATU为佳,流速1 ml/min;优化工艺在强阴离子交换HiPrep 16/10Q上放大。Sephacryl S-100凝胶过滤柱纯化水蛭素：在一定流速范围内,流速对纯化效果影响不大,上样量可在10ml左右。结果]优化的分离纯化路线为：大量发酵液→离心→三氯乙酸处理（91%回收率）→再离心→超滤浓缩脱盐（80%回收率）→乙醇沉淀浓缩（82%回收率）→强阴离子交换（90%回收率）→硫酸氨沉淀浓缩（90%回收率）→Sepharcyl S-100凝胶过滤（回收率93%）→纯品（总回收率=91%×80%×82%×90%×90%×93%=45%,纯度95.1%）。结论]可为进一步工业化分离纯化水蛭素研究提供借鉴。

Separation and Purification of Recombinant Hirudin Variant 3 from Bacillus subtilis

Objective] The research aimed to get the optimized separation and purification conditions of the hirudin produced from Bacillus subtilis DB403 （pUBH5）. Method] Through the systemic pretreatment, preliminary chromatography and fine chromatography. Result]The optimized separation and purification conditions were that： Supernatant was treated by trichloroacetic acid, then by ultrafiltration desalt and anion exchange chromatography. Strong anion Q F. F. was better than weak anion DEAE F.F. The proper balanced solution was Tris-HCI （ pH 8.0）. The proper conductivity was 6 ms/cm. The maximum applied sample was 240 ATU/ml to matrix of strong anion Q F. F. This optimized procedure was magnified in strong anion exchange HiPrep 16/10Q with the 90% recovery and 70.2% purity. The purification of gel filtration of Sephacryl S-100 to hirudin was not relative to flow rate within certain scope. The application size of sample was 10 ml. The purity checked by HPLC was 95.1%, and the recovery was 93%, and the band of SDS-PAGE was single. Conclusion] The research provided the reference of the further industrialization separation and purification of hiruin.