Isolation and molecular identification of deteriorating fungi from Cyrus the Great tomb stones

Biodeterioration is an irreversible damage that is caused by colonization of microorganisms on the surface of different materials. Among all microorganisms, fungi play an important role in deterioration of materials. Fungi can colonize on stone surfaces and by secreting different enzymes, organic and inorganic acids and pigments, can cause bio-weathering and changing not only the substrate materials but the color of stones. Furthermore, fungal mycelia can penetrate into the internal surfaces of stones and change the interior chemical contents of stones. Pasargadae including Cyrus the Great Tomb is entitled by UNESCO as one of the World Heritage Sites. This study was focused on the identification of fungi that were colonized on the tomb limestone monument.

Sampling of stone was carried out to identify inhabiting molds and yeasts. biochemical and microscopic methods were used for isolated strains. In addition, the Polymerase Chain Reaction (PCR) and sequencing of the PCR products were done. Finally, phylogenic tree was constructed basde on the sequences of ITs region.

The common inhabiting fungi which isolated from the tomb limestone belong to Caldosporium sp., Embellisia sp., Cryptococcus sp., Candida sp., Meyerozyma sp., Arthirinium sp., Ulocladium sp., Fusarium sp., Humicola sp. and Pseudozyma sp.. Stereomicroscopic and Scanning Electron Microscope images and XRD, were taken from pieces of stone samples and indicated the severe pattern damages such as pitting, biomineralization, etching and sugaring on the surfaces of stones.