毕业论文移动版

摘要中国以农业发达著称，然而每年我国都会产生超过十亿吨的农业废弃物,如水稻秸秆、玉米秸秆、花生壳等。这些残渣中含有丰富的木质纤维素如何有效地将农业废弃物中的纤维素转化为有价值的产品,变废为宝是本研究的出发点。本研究取样于山东赵庄秸秆还田土中并通过分离、筛选得到了一株微生物絮凝剂高产菌株，且命名为L804。通过分子生物学方法，我们确定了该菌株为纤维化纤维微细菌(Cellulosimicrobium cellulans)。该菌株具有很高的纤维素降解酶活，且能够利用农业废弃物作为唯一碳源，发酵产出微生物絮凝剂。我们对该菌株的发酵进行条件优化，发现以玉米秸秆作为唯一碳源，以酵母粉作为氮源，pH为8.2时，产出的微生物絮凝剂的絮凝效果最好，且产量超过4.75 g/L，而且我们的微生物絮凝剂在实际应用方面也展示了非常优良的效果，对产生物柴油微藻的絮凝率接近100%。相对现有的微生物絮凝剂生产方法，本研究利用纤维化纤维微细菌转化农业废物物玉米秸秆生产微生物絮凝剂，变废为宝，大大减低了市售微生物絮凝剂的生产成本，所以可以说是极具市场开发优势和应用前景的。 43636

该论文有图15幅，表1个，参考文献19篇。

毕业论文关键字：玉米秸秆  生物絮凝剂  纤维素酶活  产油微藻

Using Cellulosimicrobium cellulans L804 to produce MBF and researches on its characteristics

Abstract

China has been known as a large agricultural country. It produces tens of thousands agricultural wastes like rice straw, corn stover, peanuthull per year, which were rich in lignocelluloses, whose hydrolysate can be used by some strains to produce biological products How to turn these wastes into wealth is the starting point of our research. A lignocellulose-degrading strain Cellulosimicrobium cellulans L804 was isolated in this study, which can produce the bioflocculant using untreated biomasses, such as cornstalk. The results showed that when use the cornstalk as carbon source, yeast extract as nitrogen source, pH 8.2, the production of bioflocculant can reach the top to 4.75 g/L. And also, the flocculating efficiency of the bioflocculant for harvesting microalgae is almost 100%. This study gives the picture for the first time that C. cellulans L804 can directly convert corn stover to produce bioflocculants, which can be used to effectively harvest microalgae, reducing the pollution of the environment and the production cost and realize the recycling of cornstalk, so we can see the biofloccualnt has a fine application prospective and a very good market development.

  Key words: Corn stover  Bioflocculant  Cellulase activity  Microalgae harvest 

目 录

摘 要 I

ABSTRACT II

目 录 III

图清单 IV

1引言 1

1.1絮凝剂分类 1

1.2微生物絮凝剂的研究现状 2

1.3产油微藻的研究现状 2

2材料和方法 3

2.1实验材料 3

2.2实验方法 4

3 结果与分析 9

3.1 L804纤维素酶活和木聚糖酶活的发现 9

3.2初始PH的确定 9

3.3最优氮源的确定 10

3.4最优发酵碳源的确定 10 (责任编辑：qin)