目录
摘要I
关键词I
AbstractII
引言
引言1
1材料与方法2
1.1实验材料 2
1.1.1实验样品 2
1.1.2培养基 2
1.1.3试剂 2
1.1.4实验仪器及设备 2
1.2实验方法 2
1.2.1硫甙的粗提2
1.2.2硫甙降解菌株的富集、筛选与鉴定3
1.2.3菌种的生理生化实验5
1.2.4绘制菌株曲线关系图6
1.2.5菌株培养条件优化6
2 结果与分析7
2.1硫甙的粗提7
2.2降解菌株的筛选7
2.3菌株的鉴定8
2.3.1降解菌株的形态学观察8
2.3.2降解菌株16s rRNA鉴定8
2.4菌种的生理生化实验9
2.5降解菌株L9生长曲线的测定10
2.6降解菌株L9发酵条件的优化10
2.6.1降解菌株L9在不同接种量下的生长情况10
2.6.2不同温度对降解菌株L9生长的影响11
2.6.3不同pH对降解菌株L9生长的影响11
3讨论 12
3.1硫甙降解菌株的筛选12
3.2硫甙降解菌株的鉴定12
3.3硫甙降解菌株培养条件优化12
致谢13
参考文献14
菜粕中硫甙降解菌株的分离鉴定及发酵条件优化
摘要
硫甙是菜粕中的抗营养因子，它的存在降低了菜粕饲料化价值，引起养分吸收不充分，含量过高会导致动物甲状腺肿大，消化不良等问题。本文采集长期堆积菜粕的土壤样品，对土壤微生物进行室内富集培养。采用无机盐硫甙固体筛选培养基筛选出一株可以高效降解硫甙的菌株L9。该菌株在固体平板上菌落外观为圆形，表面光滑不透明，呈黄白色，干燥。通过生理生化和遗传指标的测定分析，初步鉴定该菌株为鞘氨醇杆菌属（Sphingobacterium multivorum L9）进一步进行了菌株发酵条件的优化，以硫甙降 *51今日免费论文网|www.51jrft.com +Q: #351916072# 
解率为评价指标，以接种量、发酵温度、pH为试验因素，设计正交试验，选出最佳发酵条件。实验结果表明，在接种量为4％，温度为30℃，pH为6的条件下，菌株L9生长最好。该菌株是目前已报道的降解硫甙效率最高的菌株，降解硫甙效率高达76.7%，具有较好的产业化应用前景。
ISOLATION AND IDENTIFICATION OF GLUCOSINOLATE DEGRADING STRAINS FROM RAPESEED MEAL AND OPTIMIZATION OF FERMENTATION CONDITION
ABSTRACT
Glucosinolate is an antinutritional factor in rapeseed meal. Its presence reduces the value of rapeseed meal feed, causing insufficient nutrient absorption. Too high a content will cause a lot of problem, such as animal goiter and indigestion. In this paper, soil samples were collected for longterm accumulation of rapeseed meal, andmicroorganisms were enriched and cultured indoor. An inorganic salt glucosinolate solid screening medium was used to select a strain L9 that could efficiently degrade glucosinolates. The colony of this strain is round on the solid plate, the surface is smooth and opaque, yellow and white, and dry. Through the analysis of physiological and biochemical and genetic indicators, the strain was initially identified as Sphingobacterium multivorum L9. In this study, the fermentation conditions of the strain were further optimized. The degradation rate of glucosinolate was used as the evaluation index. The inoculation amount, fermentation temperature and pH were used as the experimental factors. The orthogonal test was designed to select the best fermentation conditions. The experimental results show that the strain L9 grows best under the conditions of inoculation amount of 4%, temperature of 30 ° C and pH of 6. This strain has been reported to have the highest efficiency of degrading glucosinolates, and the efficiency of degrading glucosinolates is as high as 76.7%, which has a good industrial application prospect.

原文链接：http://www.jxszl.com/swgc/smkx/606491.html