HiPurA Plant DNA Isolation Kit (CTAB Method) 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. The CTAB method can be used both for freeze-dried leaves and for fresh leaves. The scale of extraction is dependent on the amount of starting material, for e.g. 300400 mg of material requires 9 ml of Extraction Buffer, which yields up to 500 g of DNA. Kit contains:

CTAB Extraction Buffer

RNase A Solution (20 mg/ml)

CTAB Wash Buffer Concentrate

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

CTAB Powder

CTAB (Cetyl trimethylammonium bromide), a detergent is used to break open and solubilize the contents of plant cells. Chlorophyll and some denatured proteins are removed from green plant tissue in an organic chloroform/octanol step, and the organic phase is separated by centrifugation. Since the extract contains DNA and RNA, RNA can be removed by the addition of RNase A, the DNA is precipitated and washed in organic solvents before redissolving in aqueous solution. The concentration of the DNA can be estimated by agarose gel electrophoresis. The DNA recovered is not free from contaminants such as carbohydrates, but is of suitable grade for enzyme digestion, southern blotting and analysis by PCR.