产腈水合酶菌Nocardia sp.HD9611的发酵条件优化的研究

Studies on fermentation optimization of nitrile hydratase Nocardia sp.HD9611

探讨了种龄、接种量、搅拌转速、pH及补料等因素对Nocardia sp.HD9611产腈水合酶的影响。结果表明,最佳种龄为20h;接种量对酶活的提高没有明显影响,但7.5%时最佳;当搅拌转速低于400r/min时,溶解氧将成为细胞生长的限制因子;发酵过程中pH调节对细胞量及酶活的提高有积极的作用;补料对细胞密度及酶的产生有积极影响,总糖为80g/L时,细胞量31.88g/L,提高了120.8%,酶活为7100U,提高了107.6%。此研究为制定最佳控制策略提供了参考。

The factors such as cell age, inoculum concentration, stir speed, pH and supplement fed on nitrile hydratase Nocardia sp. HD9611 were studied. The results indicated that the best cell age was 20 h. The inoculum concentration had not remarkable effect, while 7.5 % inoculum concentration was the optimum. Dissolved oxygen would become the restrictive factor of cell growth when stir speed was below 400r/min. The adjusting of pH played roles in the raising of cell growth and enzyme activity in course of fermentation. Besides, a supplement fed could increase the cell density and enzyme activity. The cell mass was 31.88g/L, increasing 120.8 % than that of the batch fermentation when the total concentration was 80g/L. The enzyme activity was 7100U , increasing 107.6% under the same conditions. This research provided some optimum control strategies and methods.