中文摘要：

采用液氮研磨法、反复冻融法、反复冻融-溶菌酶法、溶菌酶法、超声波法、超声波-溶菌酶法对节旋藻TJCU-7的藻细胞进行破碎,用改进的CTAB法提取基因组DNA,通过凝胶电泳检测,核酸浓度、纯度测定及PCR扩增效果来评价各破壁方法的优劣。结果发现,6种方法对节旋藻均有较好的破壁效果：经反复冻融法、溶菌酶法及反复冻融-溶菌酶法破壁后所获得的DNA浓度（〉2000 ng/μL）显著高于其他方法,其中液氮研磨法所得的DNA浓度最低（〈40 ng/μL）。除超声波法所得DNA的OD260/OD280值大于2.00,说明有部分RNA污染外,其余方法所得DNA的OD260/OD280的值均在1.90-2.05,纯度较高。经PCR扩增后均得到了2 kb的目的片段,可以满足基本的生物学实验要求。综合考虑,反复冻融法,溶菌酶法简单、快速,破壁效果好,是节旋藻DNA提取时的优先考虑方法。

英文摘要：

For obtaining the best cell wall-broken methods and operating conditions of Arthrospira genomic DNA extraction,six methods i. e. , liquid nitrogen grounding method, freezing and thawing method, freezing and thawing-lysozyme method, lysozyme method, ultrasonieation method and uhrasonication- lysozyme method were compared. The genomic DNA was extracted through the improved CTAB method and effects of wall-broken were evaluated based on the concentration,purity and Polymerase Chain Reaction. The results showed that all methods can break the cell wall well. The concentration of the DNA extracted after the cell wall was broken through freezing and thawing method, lysozyme method aud freezing and thawing-lysozyme method were significantly higher than the others. The purity of the genomic DNA extracted after the ultrasonic wall-breaking could not meet the standard while the other methods could. In spite of this,the DNA could all satisfy the basic requirements of molecular biology study. By overall consideration, freezing and thawing method and lysozyme method hold simple operation,are rapid and effective. They wouht he more appropriate to break the wall and obtain the DNA from Arthrospira than the other methods.