以玉米秸秆为原料,经酸碱蒸煮处理后,再经纤维素复合酶酶解,利用酶解液发酵产γ-聚谷氨酸(γ-PGA)。通过单因素和正交试验,研究了用1.0%H2SO4、10.0%NH3OH、水三种预处理方法处理玉米秸秆,以含糖量为指标考察各因素对酶解效果的影响。结果表明,3种预处理方法酶解玉米秸秆的最佳条件基本一致:加酶量为35FPIU/g,底物浓度1∶15,酶解时间96 h。玉米秸秆酶解液与玉米糖化液混合发酵生产γ-PGA的最佳配比为7∶3,与玉米秸秆酶解液单独发酵相比,混合发酵产γ-PGA产量提高了95.12%。

Corn straw was hydrolyzed by cellulose compound enzyme after steam explosion pretreatment with H2SO4 and NH3OH. The hydrolyzate was fermented to produce γ-PGA. Through single factor and orthogonal experiment,sugar content was used as index to investigate the effects of various factors on the enzymatic hydrolysis after pretreatment with 1. 0% H2SO4,10. 0% NH3 OH and water. The results indicated that the best conditions for these three kinds of enzymatic pretreatments of corn stover were almost the same as follows: the amount of enzyme was 35 FPIU /g,substrate concentration was 1∶ 15,reaction time was 96 h. The optimal ratio of corn stover saccharification solution to corn hydrolyzate for production of γ-PGA was 7 ∶ 3. The production of γ-PGA in mixed fermentation increased by95. 12% compared to fermentation with corn hydrolyzate alone.