摘要
[目的]研究1株高产脲酶的芽孢杆菌菌体的固定化及其固定化细胞的转化条件。[方法]研究不同浓度海藻酸钠溶液、菌体包埋量、戊二醛溶液对固定化细胞脲酶酶活的影响,以及不同pH值、不同温度、几种离子浓度对脲酶活力的影响。[结果]结果表明,固定化细胞转化最适pH值为7.5,最适温度为40℃,最适海藻酸钠溶液浓度为30 g/L,最佳包埋量为40 g/L,最适戊二醛浓度为2%;细胞经过固定化后,细胞脲酶稳定性显著提高,经过戊二醛交联后,稳定性再次提高。固定化细胞的脲酶对Cu2+、Hg2+的抑制作用有一定的抗性。[结论]固定化细胞比游离细胞更适合工业化操作。
[ Objective]This paper aimed to study the immobilization of cell producing urease and properties of urease. [ Method] The effects of sodiana alginate, entrapped cell quantities and gluuaral dehyde on urease activity of immobilized cell were studied.The effects of pH value, temperature and metal iotas on biotmnsfonnation were also studied. [Result] The optimum pH value of the urease of immobilized cell and temperature were 7.5 and 40 ℃ ,respectively. The urease activity of immobilized cell and recovery ratio got optimum results when the concentration of sodium alginate was 30 g/L. The best entrapped cell quantities was 40 g/L mad the urease of imnaobilized cell was more stable than that of free cell.When the concentration of glutaraldehyde was 2%, crosslinked immobilized cell showed maximum urease activity and more stability than immobilized cell before crosslinking. The immobilized cell showed re- markable resistance to inhibition of Cu2＋ and Hg2＋ . [Conclusion] The urease of immobilized cell perfomanced better than that of free cell.
出处
《安徽农业科学》
CAS
北大核心
2008年第33期14375-14377,共3页
Journal of Anhui Agricultural Sciences
关键词
尿素
脲酶
固定化细胞
海藻酸钠
Urea
Urease
Immobilized cell
Sodium alginate
