Improved method for genomic DNA extraction for Opuntia Mill. (Cactaceae)

BACKGROUND: Genomic DNA extracted from species of Cactaceae is often contaminated with significant amounts of mucilage and pectin. Pectin is one of the main components of cellular walls, whereas mucilage is a complex polysaccharide with a ramified structure. Thus, pectin- and mucilage-free extraction of DNA is a key step for further downstream PCR-based analyses. RESULTS: We tested our DNA extraction method on cladode tissue (juvenile, adult, and herbaria exemplars) of 17 species of Opuntia Mill., which are characterized by a large quantity of pectin and mucilage. CONCLUSION: We developed a method for the extraction of gDNA free of inhibitory compounds common in species of Opuntia Mill., such as pectin and mucilage. Compared to previously extraction protocols, our method produced higher yields of high-quality genomic DNA.