In order to determine the optimal growth conditions of recombinant Pichia pastoris to produce xylanase, one-factor experiment was carried out. Plackett-Burman experimental design was then used to screen ten factors including medium components and conditions of the culture during induction period. The results of ANOVA indicated that the main factors influencing the expression of xylanase were yeast extract, induction pH and rotation speed. Furthermore, the response surface method of Box-Behnken was used to optimize these three factors. The highest activity of xylanase reached 262.77 U/mL when 11.13 g/L of yeast extract was added; The pH was adjusted to 6.38 and relation speed was 228 r/min. The activity of xylanase increased by 175.44% compared to that of the original conditions. When optimized fermentation conditions were applied to 7 L fermenter for sequential induction of 120 h. The highest activity of xylanase was 2054.89 U/mL after 72 h of induction.%采用单因素实验确定重组毕赤酵母产木聚糖酶生长相的最适条件,然后利用Plackett-Burman实验设计对诱导相培养基成分和培养条件的10个因素进行筛选,方差分析结果表明,影响木聚糖酶表达的主要因子为酵母膏、诱导pH和摇床转速；在此基础上,用Box-Behnken的响应面方法对3个因素进行进一步优化,当酵母膏为11.13 g/L,pH为6.38,摇床转速为228 r/min时酶活有最大值,为262.77 U/mL,较优化前提高了175.44％.优化后的摇瓶发酵条件应用于7L发酵罐并连续诱导培养120 h,发现诱导72 h后的木聚糖酶酶活最高,为2054.89U/mL.
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