甲醇-乙醇分步沉淀法提取γ-聚谷氨酸

The extraction of γ-polyglutamic acid by methanol-ethanol fractional precipitation method

采用非单一有机溶剂即甲醇-乙醇分步沉淀法从发酵液中提取聚谷氨酸(γ-PGA),通过响应面法对聚谷氨酸(γ-PGA)提取条件进行优化。在初步考察单因素影响的基础上,以BBD(Box-Behnken design)法设计考察有机溶剂沉淀倍数、沉淀pH、沉淀时间3个因素对γ-PGA提取纯度的交互影响,用Design-Expert v8.0.6.1软件对BBD实验数据进行分析处理。试验得到的最佳提取条件为:有机溶剂沉淀倍数为3.48、沉淀pH为8.13、沉淀7.30 h,γ-PGA提取纯度为75.16%,提取率83.77%,预测精准度达99.02%。

Non-single organic solvent,methanol-ethanol fractional precipitation method was applied to extract γ-polyglutamic acid( γ-PGA) from the fermentation broth,meanwhile the extraction conditions were optimized by response surface method. Also the effects of organic solvent precipitation multiple,pH and time on the γ-PGA purity were observed through Box-Behnken design( BBD) on the premise of preliminary consideration of single factor. The results under Design-Expert v8. 0. 6. 1 software showed that the obtained optimal extraction conditions were the combination of organic solvent precipitation multiple 3. 48,pH 8. 13,and 7. 30 hours. Under the optimum extraction conditions,the corresponding values of purity and extraction ratio of γ-PGA were 75. 16% and 88. 73%,respectively. The predictive accuracy was 99. 02%.