MYCOLOGICAL AND ULTRASTRUCTURAL STUDIES TO EVALUATE BIODETERIORATION OF MURAL PAINTINGS - DETECTION OF FUNGI AND MITES IN FRESCOES OF THE MONASTERY-OF-ST-DAMIAN IN ASSISI

The role of fungi in the biodeterioration of frescos has been investig ated by microbiological and ultrastructural techniques. With this aim, the the mycoflora present on samples taken from deteriorated indoor w all paintings (frescos) in the Monastery of St Damian in Assisi was is olated and identified. The results showed that the fungal colonization of the two paintings 'Crocifisso con Francesco giovane' and the 'Mens a di S. Chiara', located inside St Clare's Refectory, was mainly due t o Cladosporium, Aspergillus, Alternaria, Penicillium and Fusarium gene ra. Although considered not uncommon in frescos, their direct involvem ent in enzymatic degradation of paints was not confirmed. Interestingl y, the presence of mites in proximity to actively growing fungal mycel ium, as revealed by scanning electron microscopy, although considered an example of parasitic nutritional relation, could also suggest a met abolic interaction resulting in the synthesis of biodeteriogenic subst ances.