不同破壁方法对活性污泥总DNA提取效果的影响

分别采用酶法、化学法、珠磨匀浆法和反复冻融法对活性污泥样品进行破壁，提取总DNA，并通过提取的核酸总量、纯度、片段分布情况、是否含有聚合酶链反应抑制剂以及基因间隔序列(ITS)扩增产物多态性等5个指标来评价不同的细胞破壁方法对活性污泥总DNA提取效果的影响。结果表明，化学法的优势最明显，提取的总量最多，大片段提取效果好，虽然杂质较多，但不影响聚合酶链反应，方法的偏倚性最小。

Evaluation of Different DNA Extraction Methods for Activated Sludge

Four different DNA extraction methods for activated sludge were evaluated. They are enzymatic lysis, chemical lysis, bead mill homogenization and freeze-thawing. The effects of them were compared based on the yield, purity, molecular size distribution of the recovered DNA, and existence of PCR-inhibitor. The bias of the four methods was evaluated according to the ITS PCR products length polymorphism. The results show that the chemical lysis is most effective and has the most total DNA yield and large size fragments, the impurities in the products by chemical lysis do not inhibit the PCR, and the bias of this method is the least.