顽拗植物龙眼基因组DNA提取方法的研究

为从顽拗植物龙眼(Dimocarpus longan Lour.)叶片中获得可供后续分子生物学操作的基因组DNA．针对其组织细胞内富含多酚、多糖、单宁及色素等物质的特点，采用改进的CTAB法和SDS法，即在核裂解之前先破碎细胞．将存在于细胞质中的次生物质去除后再裂解细胞桉．结合其它一些改进措施．提取到的DNA沉淀呈纯白色．极易溶解于TE中。两种改进方法的OD260和OD280比值分别达到1.82和1．73，其鲜叶基因组DNA产量分别为103ug/g和127ug／g：RAPD扩增条带清晰，丰富．完全满足后续分子生物学操作的要求，其中改良CTAB方法效果更为理想，与之埘比．传统的CTAB法和SDS法提取到的DNA沉淀呈浅黄色甚至红褐色，很难被TE溶解，其OD260和OD280比值均低于1．5，也得不到扩增产物。

Study on Genomic DNA Extraction from Recalcitrant Dimocarpus longan Lour.

Two different ways have been developed to extract the high quality DNA from the recalcitrant fruit tree longan(Dimocarpus longan Lour.)which contains abundant polyphenols,polysacchrides,proteins and some other secondary metabolites.The ratios of the genomic DNA extracted by the modified CTAB and SDS methods were respectively 1.82 and 1.73.The comprehensive results from electrophoresis,ratios of OD_(260nm) and OD_(280nm) and RAPD-PCR amplification suggested that the two modified methods especially the modified CTAB can produce high quality genomic DNA while the conventional CTAB and SDS methods are not suitable for the DNA extraction from longan.