响应面法优化囊酵母XHV25产果胶酶发酵培养基的研究

Optimization of Fermentation Medium for Pectinase Production from Zygoascus sp. XHV25 Using Response Surface Methodology

试验采用响应面法对囊酵母(Zygoascus sp.)XHV25液体发酵产果胶酶的培养基组分进行优化。在前期运用单因素试验优化的基础上,利用Plackett-Burman试验设计筛选出培养基组分中影响果胶酶活力的2个显著性因素:橙子皮粉和K_2HPO_4·3H_2O。运用单因素试验研究PB试验设计筛选出的不显著因素的最低添加量来降低生产成本;运用最陡爬坡试验研究PB试验设计筛选出的显著因素以找到中心复合试验的中心点。利用中心复合设计确定显著性因素之间的交互作用及最佳组成。最终得到的预测最佳培养基组分为:橙子皮粉31.2 g/L、蛋白胨1 g/L、牛肉膏3 g/L、K_2HPO_4·3H_2O 0.094 g/L、KH_2PO_4 0.5 g/L、CaCl_2 0.5 g/L,在此预测最佳培养基组分下得到的果胶酶活力为28.97 U/mL。在预测最优培养基组合下进行发酵验证性试验,得到果胶酶活力的平均值为29.02 U/mL。实测值与预测值吻合良好,由此可见该模型可较好地预测发酵后的果胶酶活力。

surface methodology （RSM） was employed to optimize a liquid fermentation medium for pectinase production from Zygoascus sp.. Based on single factor experiments used to optimize cultural conditions and the medium response, two significant influence factors were screened by the method of Plackett-Burman design as： orange peel powder and K2HPO4.3H20 For reducing the source cost, the minimum addition amount experiment was used to find out the minimum addition amount of non-significant factors. The steepest ascent design was applied to obtain the center point of central composite design. And the optimal concentration and correlations of two factors were identified by central composite design. The result indicated that the optimal fermentation components for pectinase production were as follows： orange peel powder 31.2 g/L, peptone 1 g/L, beef extract 3 g/L, K2HPO4.3H20 0.094 g/L, KH2PO4 0.5 g/L, CaC12 0.5 g/L, which the enzyme activity reached 28.97 U/mL under the forecast fermentation components. The enzyme activity in vertification test reached 29.02 U/mL, and it was consistent with the model predicted value, which showed that the model could be used to predict pectinase after fermentation.