中文摘要：

目的：分离大量完整的杜氏盐藻叶绿体,提取高纯度的叶绿体DNA（cpDNA）。方法：取对数生长后期的杜氏盐藻细胞进行高压破碎,利用差速离心和蔗糖密度梯度离心得到完整的叶绿体。采用优化的SDS-蛋白酶K-酚/氯仿/异戊醇方案抽提cpDNA,并经10 g/L琼脂糖凝胶电泳鉴定。结果：蔗糖密度梯度离心结果表明分离到了大量的叶绿体,相差显微镜及电镜观察证实所得叶绿体的完整性。紫外分光光度仪检测3个批次cpDNA的浓度蛋白酶为（2.21±0.02）mg/L,A（260 nm）/A（280 nm）为（1.772±0.012）。结论：获得了高纯度的杜氏盐藻cpDNA,为进行叶绿体的转化研究奠定了实验基础。

英文摘要：

Aim：To isolate a mass of intact chloroplasts of D.salina and extract cpDNA with high purity.Methods：Cells of D.salina from the late log phase of growth were broken by slow extrusion at 250 Pa through high pressure cell bomb.Intact chloroplasts were obtained by differential centrifugation and sucrose density gradient centrifugation.An optimized procedure SDS-proteinase K-phenol/chloroform/isoamyl alcohol was employed to extract the cpDNA,and the latter was identified using an ultraviolet spectrophotomeler and 1% agarose gei.Results： A mass of intact chloroplasts were isolated,the observation through phase contrast microscopy and electric microscopy showed the integrity of the isolated chloroplasts.The concentration of three groups of extractive cpDNA was（2.21±0.02） mg/L,A（260 nm）/A（280 nm） was（1.772±0.012）.Conclusion：This study offers a quick and efficient method for extracting plentiful intact chloroplasts and cpDNA with high purity and pave the way for constructing the stable transformation system by chloroplast of D.salina.