HiPurA Cotton DNA Isolation Kit is supplied by HiMedia. DNA extraction from plant tissues, unlike DNA isolation from mammalian tissues, remains difficult due to the presence of a rigid cell wall surrounding the plant cells. Cotton leaves contain high levels of polyphenolic compounds that irreversibly interact with proteins and nucleic acids during DNA isolation. In order to overcome the problems associated with poor quality of DNA, this kit has been developed. The kit helps to extract good quality DNA which is compatible for downstream applications. This method can be used for both on Herbarium specimens and on fresh leaves. The scale of extraction is dependent on the amount of starting material. Typical yield from 100 mg of wet weight sample is 7-12 g. This kit contains:

Solution CD1

Solution CD2

Solution CD3

Solution CD4

Solution CD5

Proteinase K

Elution Buffer (ET) [10 mM Tris-Cl, pH 8.5]

Solution CD1 used in this kit contains polyvinyl pyrrolidone that binds the phenolic compounds. In the presence of PVP, phenolics adhere to DNA in solution and form a coloured extract around DNA, which can be removed by the addition of Solution CD2 containing SDS. A high molar concentration of NaCl in Solution CD4 increases the solubility of polysaccharides in ethanol, effectively decreasing co-precipitation of the polysaccharides and DNA. Solution CD5, containing LiCl, for selective precipitation of large molecules of RNA thereby reducing the amount of RNA in final DNA concentration. Finally, pure DNA is eluted in Elution Buffer (ET). The concentration of DNA can be estimated by agarose gel electrophoresis.