The regularity of the simultaneous sacchanfication and fermentation of yeast for the production of ethanol was studied The effects of the conditions of wet explosion , the amount of cellulase , β-glucosidase , xylanase and the pre-enzymatic hydrolysis time on the simultaneous saocharification and fermentation were studied by single factor method . The results showed that the wet oxidation explosion for the rice straw under different conditions had obvious effects . The pretreated feedstock at 160℃ , the inlet pressure 4×1O5 Pa , the alkalic amount 6％ (w/w ) , the reaction time 20 min could improve the saccharification and fermentation efficiency . The optimal conditions obtained through the simultaneous saccharification and fermentation (SSF) were as follows : the cellulase 20 IU/g cellulose , β-glucosidase 40 IU/g cellulose , xylanase 800 IU/g at 45℃ for 8 h prenzymatic hydrolysis and 72 h SSF hydrolysis . The best conversion of ethanol with 85％ was obtained , based on the dry mass of cellulose . The conversion yield of ethanol was up to 70％ on the substrate 100 g/L cellulose .The method of the simultaneous sacchanfication and fermentation for the production of ethanol using the wet-oxidation exploded rice straw was feasible for the industrial prospect .%探讨了木质纤维素经过湿氧化爆破后在同步糖化发酵过程中酵母产乙醇的基本规律.采用单因素方法对湿氧化爆破条件、酶系组成和添加量以及预酶解时间和温度进行了优化.不同湿氧化爆破预处理条件下的稻秆对同步糖化发酵工艺的影响较大,在预处理温度160 ℃,进氧压力为4×105 Pa,碱用量为6%(w/w),反应时间为20 min的条件下得到的爆破料有利于纤维素的糖化和发酵过程;在添加纤维素酶20 IU/g纤维素、β-葡萄糖苷酶40 IU/g纤维素、木聚糖酶800 IU/g纤维素后,45 ℃预酶解8 h,38 ℃下同步糖化发酵,得到最佳乙醇产量,相对于纤维素的乙醇得率为85%,在底物浓度达到100 g/L以上,乙醇转化率仍能达到70%左右.湿氧化爆破料采用同步糖化发酵工艺制备乙醇是可行的,具有较好的工业前景.
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