SUSTAINABLE COMPOUNDS CONTRAST THE PROLIFERATION OF DAMAGING MICROORGANISMS THAT COMPROMISE THE INTEGRITY CULTURAL HERITAGE

The Italian cultural heritage is the largest in the world with its 49 recognized sites known as "Human Heritage" in the UNESCO World Heritage List (http://whc.unesco.org/en/list/). In this context characterized by a huge amounts of monuments and stone works of art, it is very important the preservation and the storage of cultural heritage including archeological sites. Stone monuments, statues and historic buildings are exposed to the effects of physical, chemical and biological deteriorating factors. The damage caused by microorganisms, in a process referred to as biodeterioration, is due to the colonization of different groups of microorganisms, including bacteria, cyanobacteria, algae and fungi. Heterotrophic bacteria including a variety of genera such as Arthrobacter, Bacillus, Paenibacillus, Flavobacterium, Pseudomonas, Micrococcus, Staphylococcus, Nocardia, Mycobacterium, Streptomyces and Sarcina, have been frequently isolated from wall paintings but also in caves and catacombs (Pangallo et al. 2012a; Warscheida and Braamsb, 2000b). Moreover, halophilic species of the Gammaproteobacteria (such as the genera Idiomarina, Salinisphaera and Halomonas) and Firmicutes (Halobacillus and Bacillus spp.), but also species of the phyla Bacteroidetes and Actinobacteria (as Rubrobacter) and Archaea (Halococcus and Halobacterium), have often been detected on salt-attacked monuments (Ettenauer et al. 2012c; Piñar et al. 2013d). Since many of these microorganisms contain carotenoid pigments in their cell membranes their proliferation produces typical rosy stains on the wall surfaces. This work reported the preliminary results obtained in the frame of the "ICB4ART Project", a multidisciplinary approach born with the aim to protect the cultural heritage based on the expertise in microbiology, chemistry of natural compounds and organic chemistry. The "ICB4ART Project" is built on the use of natural or eco-friendly synthetic products, in order to contrast the proliferation of damaging microorganisms that compromise the cultural heritage. Report regarding the first results based on anti-bacteria test of some selected compounds, carried out by biocidal test (both in liquid and in solidified media), will be described.