响应面法优化细菌纤维素发酵合成工艺

Optimization of Bacterial Cellulose Fermentation Conditions by Response Surface Methodology

目的对细菌纤维素高产菌株葡糖醋杆菌G-29进行发酵优化,以提高其细菌纤维素合成能力。方法采用基于非完全平衡块原理的Plackett-Burman(PB)试验设计法,筛选出了3个主要影响因子:混合碳源(葡萄糖∶蔗糖=1∶2),MgSO4,乙醇,然后采用Box-Behnten中心,组合试验设计和响应面分析方法(RSM)确定其最佳浓度分别为混合碳原52.3g/L,MgSO40.159 8 g/L,乙醇32.5 ml/L。用扫描电镜观察了细菌纤维素的形态结构,并通过X射线衍射分析其在干态下和湿态下的最佳结构。结果在优化培养基条件下,菌株G-29发酵生产细菌纤维素的产量为11.83 g/L,是优化前产量(6.20 g/L)的1.9倍。结论PB试验和RSM相结合的试验方法,用于优化G-29发酵培养基,不仅科学合理而且准确有效。

Objective In this manuscript, the optimal conditions for cellulose production by gluconacetoba - ater G - 29 were determined in order to improve the yield of bacterial cellulose. Methods Plackett - Burman Design was used to evaluate three statistically significant parameters including mixed carbon sources （Glucose：sucrose = 1：2 ） , MgSO4, ethanol. The optimal levels of three variables were defined by Box - Behnken design and response surface method （ RSM ） ： mixed carbon sources ： 52.3 g/L, MgSO4 0. 159 g/L, ethanol 32.5 g/L, ethanol 32.5 g/L comparison. The morphology of bacterial cellulose （ BC ） produced was observed by scanning electron microscope（SEM）. The crystal structure of BC in dried and wet state was studied by X -ray diffractometry （XRD）. Results The results indicated that the BC yield under the optimal fermentation medium was 11.83 g/L,which was as 1. 9 times as that under the original fermentation medium. Conclusion The method of PB design combined with RSM used for optimization of G - 29 fermentation medium is scientific and accurate.