A Simple Method for Optimal DNA Extraction from Different Filamentous Fungi Species Growing on Earthen Walls of ‘Vale Histórico Paulista’, São Paulo, Brazil

This study aims to describe a new simple and efficient method of extracting DNA from filamentous fungi isolated from historical earthen walls. This method involves growing the mycelium on overlapping cellophane discs on solid medium and the disruption of the fungal cell wall by a combined action of liquid nitrogen and a lytic enzyme. The extraction is performed with the PureLink ™ Genomic DNA Mini Kit protocol from Pure Genomic. The full procedure can be completed in two hours. The new genomic DNA extraction protocol provided good quality and quantity of fungal DNA, from fungal mycelium, with an average yield of 27 ng/µL of DNA per sample. Purified DNA samples yielded 25 ng of DNA ready for sequencing. PCR amplifications of the DNA extracted using the new method were more successful than those extracted using the CTAB method. Thus this new extraction protocol is demonstrated to be an effective method for the identification of a wide range of filamentous fungal species that affect the integrity of buildings with earthen architecture.