摘要： 壳聚糖无毒、无，是一种用途广泛，十分有利用价值的天然高分子化合物。天然甲壳素脱乙酰即可获得壳聚糖。本文对以赭曲霉(Aspergillus ochraceus)菌丝体为原材料生产壳聚糖（chitosan）过程中的脱乙酰方法进行了优化。通过研究NaOH浓度、碱处理时间、菌体与碱液比例对赭曲霉生产壳聚糖的脱乙酰度的影响，结果表明，NaOH浓度越高，脱乙酰度越高，当NaOH浓度为20%时，脱乙酰度达到90.2%；碱处理时间越长，脱乙酰度越高，当碱处理时间为2h，脱乙酰度等于91.3%；菌体与碱液比例为1:20时，脱乙酰度达到90.8%。本研究可为赭曲霉发酵生产壳聚糖的应用奠定基础。48209

毕业论文关键词： 壳聚糖；赭曲霉；脱乙酰；优化

Optimization of deacetylation in the production of chitosan by Aspergillus ochraceus

Abstrcat: Chitosan is non-toxic, tasteless, widely used and valuable natural high molecular compound. Chitosan can be obtained by natural product chitin by deacetylation. In this study,  Aspergillus ochraceus mycelium was used as raw materials for the production of chitosan. The methods for deacetylation of chitosan were optimized. The influence of the degree of deacetylation of the concentration of NaOH, the time of NaOH treatment and the proportion of thalli and alkali liquor were studied. Result show that when the concentration of NaOH was higher, the degree of deacetylation was higher. When the concentration of NaOH was 20%, the degree of acetylation was 90.2%. The time of NaOH treatment was longer, the degree of deacetylation was higher. The time of NaOH treatment was 2h, the degree of deacetylation was 91.3%. The proportion of thalli and alkali liquor increased to 1:30, the degree of acetylation was 91.5%. Results in this study can be used in the chitosan production by A. ochraceus.

KeyWords: Chitosan; Aspergillus ochraceus; Deacetylation; Optimization 

目录

1绪论 1

1.1 壳聚糖 1

1.1.1 壳聚糖性质 1

1.1.2 壳聚糖的应用 1

1.2 壳聚糖的制备 2

1.2.1 甲壳类动物制备壳聚糖 2

1.2.2 微生物制备壳聚糖 2

1.3 赭曲霉 3

1.4 甲壳素脱乙酰化原理 3

1.5 测定脱乙酰度的原理 5

1.6 壳聚糖含量测定原理 5

1.7 本课题的研究目的和意义 5

2材料与方法 6

2.1 材料 6

2.1.1 菌种 6

2.1.2 实验材料 6

2.1.3 主要仪器和设备 7

2.1.4 培养基 8

2.1.5 试剂的制备 8

2.2 实验方法 9

2.2.1 赭曲霉菌丝体发酵培养 9

2.2.2 菌丝体收集及处理 10

2.2.3 碱法脱乙酰制备壳聚糖的单因素试验 10

2.2.4 酸处理 11

2.2.5 壳聚糖提取 11

2.2.6 脱乙酰度的测定方法 11

2.2.7 壳聚糖的含量测定 12