Validation of Direct Boiling Method for Simple and Efficient Genomic DNA Extraction and PCR‐based Macroalgal Species Determination

A rapid, simple, and cost-effective total DNA extraction method referred to as a direct boiling method for PCR-based algal species determination was validated using representative species of green, brown, and red algae. Each sample was briefly minced in two buffers, Tris-EDTA (TE) or PCR buffer, and transferred to a heat block for boiling at 98°C for 5 min. No detergent was used in this experiment. The entire DNA isolation procedure was completed within 10 min. After brief centrifugation, the supernatant was directly used as a template for PCR. As a result, all genomic DNA markers were successfully amplified and sequenced from each algal taxon. Regardless of DNA quality, the direct boiling method is very suitable to identify unknown species of algae from a large amount of samples in a limited time and can be applied broadly to routine seasonal or annual monitoring of algae. DNA from an Undaria pinnatifida sporophyte, however, was not successfully extracted by this direct boiling method, probably due to a high concentration of polysaccharides.