中文摘要：

为获得高质量肠道细菌总DNA用于研究膳食纤维对大鼠肠道菌群的影响,本实验以SD大鼠为实验动物,灌胃番茄皮膳食纤维,收集大鼠粪便及盲肠,-70℃冰箱保存。分别采用Tiangen细菌基因组试剂盒法、蛋白酶K-十六烷基三甲基溴化铵（CTAB）法和溶菌酶法提取粪便和肠道中的细菌总DNA,通过琼脂糖凝胶电泳、细菌通用引物PCR扩增和变性梯度凝胶电泳（DGGE）对提取效果进行观察比较,发现将溶菌酶法进行改进后,可以获得满意效果。改进后的溶菌酶法与另外两种方法比较,具有成本低、时间短、DNA得率高和多样性好等特点;该方法获得的DNA样品适合于用DGGE技术分析大鼠粪便及肠道菌群。

英文摘要：

In this study,SD rats were fed dietary fiber from tomato skin for understanding the effect of dietary fiber on intestinal flora.The feces and cecum of rats were collected and stored at-70 ℃.Bacterial genomic DNA was extracted from feces and cecum using TIANamp bacterial DNA kit,proteinase K-CTAB（cetyltrimethylammonium bromide） and muramidase protocol,respectively.The extracted DNA was assayed by agarose gel electrophoresis,bacterial universal primer PCR and denaturing gradient gel electrophoresis（DGGE）.Results showed that more and better DNA was extracted by using modified muramidase method with lower cost and shorter extraction time when compared with other methods.Therefore,the modified muramidase protocol is the best for DNA extraction from feces and cecum of rats.