【摘要】 研究了以聚乙烯醇为载体制备微囊化脲酶基因工程菌的方法。结果表明:微囊制备的适宜条件是聚乙烯醇 (平均聚合度为2450) 浓度为6% (w/v),海藻酸钠添加量为0.1%,气流量为3L/min,射流量为1ml/10min,包菌量为8% (w/v),反应时间24h,交联剂为含2% CaCl2 的饱和硼酸溶液,并用Na2CO3 调节pH值到6.5,在该条件下制备出的微囊细胞平均粒径为18~20mesh,机械强度远远高于对照组APA微囊,其细胞酶活性较未包埋的游离细胞略有下降。更多还原

【Abstract】 The method of encapsulation of urease genetically engineered bacterial cells by using polyvinyl alcohol (PVA) as the carrier was studied in this paper. Results showed that the optimized conditions of entrapment consist of PVA (2450) 6% (w/v), sodium alginate 0.1% (w/v), the air flow rate 3 l/min, the liquid flow rate 1ml/10min, bacterial cells 8% (w/v), crosslinking for 24h. The pH value of crosslinking agent which was made up by saturated boric acid solution and 0.2% CaCl2 was adjusted to 6.5 by Na2CO3. The average diameter of microcapsules prepared under these optimized conditions was 18~20mesh, and mechanical strength was much higher than APA microcapsules. The urease activity of encapsulated bacterial cells had a slight loss when compared with that of free bacterial cells.更多还原