【作者】 李萌；

【导师】 孙宝盛；

【作者基本信息】 天津大学 ， 环境工程， 2009， 硕士

【摘要】 我国是农业大国,玉米芯是我国农业的主要副产品,如果不能充分利用,将会危害环境。本文采用固态发酵的方法,对以玉米芯为原料生产蛋白饲料的可行性进行研究。利用Plackett-Burman、Box -Behnken设计和SAS、MATLAB软件,确定最佳辅料,并通过响应曲面法确定最优辅料配比。以玉米芯为主料,选取秸秆、玉米面、荞麦皮、酵母、废水、尿素、NaH2PO4、K2SO4、CaCl2、NaCl十种辅料,利用Plackett-Burman实验设计,得到不同配比培养基。以康宁木霉和白地霉为发酵菌种,以1:1比例混合,对以上培养基进行固态发酵过程。在不灭菌条件下,其工艺参数为:接种量10ml,发酵时间为5d和7d,发酵温度为29℃,培养基含水率为70%。利用SAS系统软件,以粗蛋白为考察指标,进行最佳辅料筛选,初步确定尿素为最佳辅料。以纤维素酶活性为考察指标,进行最佳辅料筛选,初步确定,尿素、CaCl2、NaCl三种为最佳辅料。以纤维素酶活性为考察指标,采用中心组合设计及二次响应曲面法对最优辅料配比进行优化,结果为:玉米芯:尿素:CaCl2:NaCl=10:0.3261:0.1397:0.0713的混合比例为中心组合设计的中心值,即最佳辅料优化质量比。考察培养基中尿素投加比例对粗蛋白含量的影响,测定发酵时间为5d和7d产品粗蛋白含量,得到结果为:培养基中尿素投加比例为1.5%时对粗蛋白含量影响最明显。更多还原

【Abstract】 China is a large agricultural country.Corncob is the main byproduct of agriculture . If it is not fully utilized, it would contaminate environment. In this paper, protein-feed production from corncob was studied by the solid state fermentation(SSF). Using Plackett-Burman design, Box -Behnken design, SAS and MATLAB to determine the better factors of the auxiliary materials. And take advantage of response surface method to optimum the best proportion of the auxiliary materials.Corncob was the main material in the experiment. We selected ten auxiliary materials:straw, cornbread, buckwheat husks, wastewater, yeast, NaH2PO4, K2SO4, urea, CaCl2, NaCl. With Plackett-Burman design to prepare the medium of different auxiliary materials.The solid state fermentation with two strains which were Trichodema- koningii and Geotrichum candidum.They mixed in 1:1. The process parameters were inoculation volume 10ml,cultivate temperature 29℃, non-sterile, substrate moisture 70% ,cultivate time 5d and 7d.With Plackett-Burman design to determine the better factors of the auxiliary materials by the cellulase activity and crude protein as the investigate index sign. The results showed that the better auxiliary materials were urea, CaCl2 and NaCl.Take advantage of response surface method to optimum the best proportion of the auxiliary materials. The experimental results showed that the best proportion of the quantity was corncob: urea:CaCl2:NaCl=10:0.3261:0.1397:0.0713.Crude protein as the investigate index sign, the results showed that the best proportion of urea was 1.5%.更多还原