在重组毕赤酵母生产脂肪酶的提取中,应用并优化了陶瓷膜微滤除菌工艺,确定了最佳条件为膜截留分子量500 kDa、膜操作压力0.3 MPa、温度20℃、湿菌体含量35％,先对发酵液稀释1.5倍后再进行洗滤.40L处理量的小试结果显示,在5h处理时间内,能获得高达92.70％的酶活回收率.560 L处理量的中试放大,酶活回收率为89.91％,耗时5.5h.在膜的清洗与再生中,采用2％ NaClO和2％NaOH在60℃、0.3 MPa膜压力下进行清洗40 min,清水膜通量恢复率为98.14％.陶瓷膜与板框除菌的比较试验发现,两种方法都获得了微生物限量合格的产品和较高的酶活回收率,但陶瓷膜微滤的滤液微生物检出量更低,处理时间较短,动力能耗更低,易与超滤膜耦合提取,废水产生量更少,菌体废渣易于回收,是一种节能减排、清洁环保的新型除菌工艺.%In this research, ceramic rrEmbrane microfiltration was applied to separate Pichia pastoris cells in the process of production of Rhizopus chinensis lipase. The optimal conditions were 500 kDb MWCO with trans-membrane pressure of 0.3 MPa, ternpreture of 20 ℃ , wet cell content of 35% (w/v) and 1.5 times dilution of the fermentation broth before rricrcfiltration sterilization with ceramic membrane. In the 40 L broth microfiltrating treatment, the results showed that the lipase activity recovery of 92.70% was obtained after 5 h operation. Scaling up to 560 L, the lipase activity recovery of 89.91% was obtained after 5.5 h operation. On the industrial production scale, the total membrane area of ceramic membrane microfiltraticn could be increased to 115% -120%, based on the unit membrane area treatment capacity of 17017m2. After rinsing with 2% NaClO and 2% NaOH at 60 ℃ and 0.3 MPa for 40 minutes, the recovery of ceramic membrane could reach 98.14% of the water flux. Gmpared with frame filter, both methods could achieve high lipase activity recovery and qualified products, However, the method of ceramic membrane microfiltration had advantages, such as shorter operating time, lower energy consumption, fewer wastewaters and higher quality of the products with fewer microorganisms. Moreover, the cell wastes were easy to be recovered for producing yeast extract. Microfiltration with ceramic membrane was an energy-saving, emissicn-reducing, daning-up and environment-friendly sterilization technology.
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