A protocol for the isolation of DNA from Trochetia boutoniana

Various problems are encountered during DNA extraction from plant species harbouring high levels of secondary metabolites and polysaccharides. Trochetia species are known to synthesize a wide spectrum of polyphenols including flavonoids. These compounds represent a significant barrier to the extraction of pure genomic DNA. This study describes, for the first time, a reliable protocol for extracting good quality DNA in reasonable amount from Trochetia boutoniana, the National flower of Mauritius. DNA was isolated using the Porebski et al. (1977), method but with various modifications made. This modified protocol used 1.6 M NaCl, 2% CTAB and 2.5% PVP of molecular weight 40,000, 0.5% βmercaptoethanol and an incubation period of 35 min at 60C. The purity of the extracted DNA was assessed by spectrophotometry. The quantity of DNA obtained was equivalent to 238.5μg per gram of fresh leaf material and it was amenable to restriction digestion.