Comparison of Three DNA Extraction Kits for Assessment of Bacterial Diversity in Activated Sludge, Biofilm, and Anaerobic Digestate

Abstract

Direct DNA analysis is the most widely used approach for microorganism characterization in natural and built environments; therefore, reliable and effective methods of nucleic acid extraction for samples from particular types of environments are needed. In this study, we compared three commercial kits for metagenomic DNA extraction from three types of biomass: activated sludge, biofilm, and anaerobic digestate. The yield, purity, and quality of DNA were measured, and the effect that the DNA kit had on the subsequent microbial community analysis was assessed with amplified ribosomal intergenic spacer analysis (ARISA). Amplicons were analyzed automatically utilizing capillary electrophoresis. For the activated sludge and digestate, the suggested kit is FastDNA™ Spin Kit for Soil (MP Biomedicals). This kit allowed the highest DNA yield to be obtained and provided the highest biodiversity. For biofilm with a high content of extracellular polymeric substances, the FavorPrep™ Soil DNA Isolation Mini Kit (FAVORGEN) is recommended. This kit allowed to obtain the highest biodiversity and provided the most reliable results of genetic distance assessment in this type of biomass.