Comparison of dry- and wet-based fine bead homogenizations to extract DNA from fungal spores

摘要

The present study explored DNA extraction kinetics from fungal spores, i.e., Aspergillus niger, Penicillium chrysogenum and Cladosporium sphaerospermum, by fine bead mill homogenization. In particular, the study aimed to investigate basic differences between the dry- and wet-based methods. The results showed higher initial rates of the DNA extractions by the dry-based method than by the wet-based method, due to higher collision efficiency among fine beads and fungal spores. Based on the experimental results, we constructed kinetic models. While the results by the wet-based method were fitted well with an existing first-order release-degradation model, the results by the dry-based method were not fitted well. Meanwhile, a newly constructed first-order release-degradation model, assuming a proportion of the DNA remained inside the disrupted spore cells and protected from further sheer stress, showed good correlations. The real-time PCR assays showed the PCR efficiencies of the DNA obtained by the dry-based method were higher than those by the wet-based method likely due to increased moderate fragmentation of the DNA by the dry-based method. Thus, although wet-based methods have been commonly used, dry-based methods might also be applicable to achieve efficient extraction and PCR amplification of fungal DNA.