Optimization of Two Different Modified Methods for High Quality and Quantity Extraction of DNA from Microalgae

DNA extraction is one of the first tasks in the genomic study, and finding an effective protocol for the isolation of DNA is essential in genetic engineering and most microbiology studies. DNA extraction from microalgae has always been a challenge for microbiologists due to their tough and complex cell walls and inhibitory substances in their cellular structures. Also, inefficient or differential DNA extraction of microalgae community members can lead to bias in downstream community analysis; therefore, pure DNA extraction for molecular studies is of particular importance. In this study, the efficacy and experimental variability of two modified protocols (Phenol/Chloroform’s method, and dellaporta DNA extraction’s method) for total genomic DNA extraction from four microalgae were studied. The selected microalgae for this study were Dunaliella salina, Haematococcus pluvialis, Nannochloropsis oculata, and Spirulina platensis. The concentration of DNA was measured using Nanodrop and agarose gel electrophoresis. Both modified and optimized methods used in this study showed reliable and effective results and can be recommended for future studies; However, the results indicated that optimized phenol/Chloroform’s method is preferable to the dellaporta DNA extraction’s method. The highest obtained amount of DNA was related to Dunaliella salina (815.1 and 506.8 ng/μL) in phenol/Chloroform and dellaporta DNA extraction’s method, respectively; and the lowest amount was related to Spirulina platensis with concentration 112.4 ng/μL (in Phenol/Chloroform’s method) and 30.5 ng/μL in dellaporta DNA extraction’s method. The extracted DNA was free from protein and polyphenolic/ polysaccharide compounds, therefore, they are recommended to all molecular studies on Microalgae.