Isolation of high-quality RNA free of contaminants, such as polyphenols, proteins, plant secondary metabolites, and genomic DNA from plant tissues, is usually a challenging but crucial step for molecular analysis. We developed a novel protocol based on the cetyltrimethylammonium bromide method to isolate high-quality RNA from blackberry plant tissues, especially fruits. Most DNA was removed when acetic acid was utilized, before RNA precipitation. Thus, lithium chloride, a reagent widely used for RNA purification, was not needed. The isolation time was shortened to less than 3 h.
Three DNA extraction protocols were compared for their ability to yield DNA from the leaves of herbarium specimens of nine species from nine genera of the Papilionoideae. We tested two protocols that use classic procedures for lysis and purification with cetyl trimethylammonium bromide (CTAB); a third protocol used a Nucleospin Plant kit. DNA obtained from all three procedures was quantified and tested by PCR. Test results indicated the superiority of one of the CTAB protocols. We made some modifications, developing a protocol that produced high-quality DNA from all nine species.
In order to investigate the mutation characteristics and to further examine the genetic variation of mutant sunflower (Helianthus annuus) obtained in plants grown from seeds exposed to space conditions, only the mature tissues such as leaf and flower could be used for DNA extraction after mutation characteristics were confirmed. The rich contents of polysaccharides, tannins, secondary metabolites, and polyphenolics made it difficult to isolate high-quality DNA from mature leaves of sunflower according to previous reports.