【作者】 李雪；

【导师】 孙君社；

【作者基本信息】 中国农业大学 ， 食品科学， 2002， 硕士

【摘要】 本文主要对秸秆固态发酵生产酒精所用的菌种和工艺路线进行了初步的研究，得到了以下研究成果： 秸秆经过揉搓粉碎等处理后，选取酸、碱和蒸汽爆破等三种方法进行预处理，综合考虑纤维转化率、对设备的要求、环境污染等因素，确定预处理采用蒸汽爆破法，在1.2MPa下持压5min。 利用康氏木霉固态发酵生产纤维素酶曲，酶曲的培养条件是：秸秆粉：麸皮=1：1，固液比=1：3，添加2％的硫酸铵，接种5％，30℃培养84小时左右。 利用电场诱导原生质体融合技术将产酒率高的菌株Sb1和耐高温但产酒率低的No.30进行融合，培育耐高温酵母，以达到酵母发酵温度与纤维素酶解温度相一致。通过对两亲株进行遗传标记，用3.5％蜗牛酶处理原生质体，在脉冲强度、宽度、次数为11KV、10μS、2次时进行融合，得到了可在45℃产酒精能力为7.28％的酵母融合株2。 在同步固态发酵中，采用单因素及正交实验对发酵条件和工艺参数进行了研究，在纤维素酶曲用量42IU/g(FPA)，加水比1：2的情况下，接种酵母5％，45℃发酵24小时可产生酒精7.2％(按秸秆干基计算)。更多还原

【Abstract】 The procedure for obtaining ethanol from corn straw by Simultaneous Solid-Fermentation was studied in this paper.The influence of the acid hydrolysis & enzymatic hydrolysis & press boiling and explosion showed the press boiling and explosion fit straw pretreatment. It was in 1.2 MPa and 5 minutes.The factors including medium, water contents, nitrogen sources, cultural time and cultural temperature were described for producing cellulase by the mutant strain of Trichoderma koningii then. The results showed that the optimum conditions of solid fermentation are straw: wheat bran = 1:1, the rate 1:3 of solid and liquid, (NH4)2SO42%, 30C cultivation 84 hours.Protoplast fusion between S. cerevisiae No.30 and S.bayanusl had been carried for resolving the difference of enzyme and yeast in Simultaneous Sacchrification and Fermentation. Sbl is a high alcohol yield yeast but can’t grow at 45 C. However No.30 can grow at 45 C but has a lower alcohol yield The best intensity, width, inter and frequency of the electrofusion impulse were 11Kv, 10 u S, 2 respectively. The results showed that the fusant greatly expressed the properties of parent strains in thermotolerance and ethanol yield. The fusant 2 has a high ethanol yield (7.28%) using glucose as substrate at 45C.The optimum conditions of Simultaneous solid-state fermentation were investigated by using orthogonal test. We got 7.2% ethanol from corn straw(dry) in the condition of 42IU/g (FPA) cellulase substrate, 2:1 water, 5%yeast, 45C fermentation 24 hours.更多还原