摘要：本实验采用平板划线纯化法，从自然界中分离出9支菌株，以各菌株发酵液对高岭土悬浊液絮凝效率为指标，筛选出一株高效的微生物絮凝剂产生菌。在实验过程中，分别考察了培养基中不同碳源、氮源、pH、氯化钠浓度，以及培养时间对菌株产絮凝剂特性的影响。结果表明，该株菌最佳培养基是牛肉膏蛋白胨培养基，在pH为9，氯化钠浓度小于2%的培养条件下该细菌产生絮凝剂效果最好，在牛肉膏蛋白胨培养基中培养24小时该细菌即能达到生长静止期。64137

毕业论文关键词：微生物絮凝剂   筛选   絮凝率   培养条件

毕业设计说明书（论文）外文摘要

Title   Screening and Optimum Culture Conditions of Bacteria Producing Bioflocculants                                

Abstract Streak plate purification was used to separate different strains from the nature, which ccould produce flocculants. Nine strains were screened. A high efficient strain was found through treating kaolin suspension. In the process of experiment, we focused on the effects of carbon sources, nitrogen sources, media pH, sodium chloride concentration of media and incubation time on strain culture. Results showed that the optimal media was beef extract peptone medium. The best media pH was 7-9. Concentration of NaCl in the media was less than 2%. The quality of bioflocculants was best under the optimum culture condition. The strain was able to enter resting stage in 24 hours.

Keywords  Bioflocculants   Screening   Flocculating Rate  Culture Condition

1 绪论 1

1.1 水污染现状 1

1.2 传统絮凝剂 1

1.2.1 无机絮凝剂的研究 1

1.2.2 有机絮凝剂的研究 2

1.3 微生物絮凝剂 2

1.3.1微生物絮凝剂的研发史 2

1.3.2 国内外对微生物絮凝剂的研究现状 3

1.4 微生物絮凝剂特点 5

1.5 微生物絮凝剂研究方向和前景 6

2 实验部分 7

2.1 材料 7

2.1.1 菌种来源 7

2.1.2 培养基 7

2.1.3 仪器 7

2.1.4 药品 8

2.2 实验方法 8

2.2.1 固体培养基的制备 8

2.2.2 高岭土悬浊液的配置 9

2.2.3 菌种的分离 9

2.2.4 菌种的初筛 9

2.2.5 菌种的复筛 9

2.2.6 絮凝率的测定 9

2.2.7 培养基碳源的选择 10

2.2.8 培养基氮源的选择 10

2.2.9 培养基pH的选择 10

2.2.10 细菌耐盐性的研究 11

2.2.11 培养时间对细菌产生絮凝剂的影响 11

2.2.12 助凝剂CaCl2的影响 11

3 结果与分析