Monitoring the seasonal dynamics of microalgae in the South Sea of Korea by use of a cytochrome c oxidase I DNA barcode

Microalgae are important primary producers in the marine environment, and are also important sources of health foods and medical products. Rapidly growing microalgae have potential use for the production of commercial products, but can also cause harmful microalgal blooms in natural ecosystems. There are many available techniques for the identification of microalgae in natural ecosystems. We used the mitochondrial cytochrome c oxidase subunit I gene as DNA barcode to identify 14 species of microalgae from the South Sea of Korea and to discriminate among similar biogeographic subgroups within species. In addition, we designed species-specific primers targeting the cytochrome c oxidase subunit I gene to evaluate monthly changes of microalgae throughout the year. Chaetoceros brevis, Asterionellopsis glacialis and Stephanopyxis turris were present during all seasons, whereas Skeletonema japonicum, Nitzschia improvisa, Ditylum brightwellii and Chaetoceros diadema were only detected during winter and spring. Our results indicate that species-specific polymerase chain reaction of the cytochrome c oxidase subunit I gene can be used to monitor the seasonal dynamics of microalgae in the South Sea of Korea. This polymerase chain reaction detection method successfully identified the 14 most common species of microalgae with the same polymerase chain reaction condition near Tongyeong, in the South Sea of Korea.