Molecular Identification of deteriorating Aspergillus spp. from sandstone monuments

Abstract

Biodeterioration is irreversible damage that is caused by the colonization of bio communities on the surface of sandstone monuments. Out of all bio communities, fungi play the most vital role in the deterioration of sandstone. Fungi can colonize on the surface of sandstone and by releasing many types of inorganic and organic acids, pigments and enzymes, can changing not only the surface of the materials but the color of the sandstone. Moreover, mycelia of fungi can penetrate into the internal surface of sandstone and change the interior chemical contents of sandstone. This study was focused on the identification of fungi that were colonized on the sandstone monument. The samples were collected from different monument places built during different time periods and analyzed using cellophane tape methods and swabbing & serial dilution methods. A sampling of stone was carried out to identify inhibiting microorganisms. Biochemical and microscopic methods were used for isolated strains of samples. In addition, the Polymerase Chain Reaction (PCR) and sequencing of the PCR products were done. Finally, the phylogenic tree was constructed base on the sequences of ITs region. We identify high microbial diversity in fungal groups . The fungal commodity structure differed among the samples. The inhabiting fungi which isolated from sandstone monuments belong to high microbial diversity fungal groups. The result revealed that the strain exhibited a high level of 18S rRNA similarity with Aspergillus costaricaensis, Aspergillus luchuensis was identified as a close relative to Aspergillus spp.