MODERN TECHNOLOGIES FOR CONSERVATION OF VILLA ZITO PAINTINGS COLLECTION (PALERMO – SICILY)

Abstract

In this study we describe the conservative integrated approach performed on 40 paintings, dating from different period (XVII- XX century), belonging to “Fondazione Sicilia “ and exposed in Villa Zito paint gallery in Palermo (Mazzocca 2015). Through a multidisciplinary approach both constitutive materials and state of conservation have been determined. Particularly, pigments and executive techniques were identified by non-invasive diagnostic investigation (XRF analysis, UV fluorescence acquisition, and IR Reflectography) as well as previous restorations events. The study has included the revealing of microbial colonization by using non-invasive sampling methods (Nylon membrane fragment) and molecular biology tools for the identification of microbial taxa (Palla et al 2010). For this reason another aim is the application of sustainable methods as alternative to traditional restoration procedures, which can sometimes be detrimental for artworks, humans and environment. In particular, in vitro culture (Nutrient, Sabouraud agar), optical microscopy observations (O.M.) and molecular biology investigations (genomic DNA extraction, PCR, sequencing and sequence analysis) reveal the presence of bacteria colonies belonging to Micrococcus sp., Staphylococcus sp. and Bacillus sp. In order to remove undesired layers appropriate cleaning protocols have been tested, using gelled solutions at specific pH values or dry cleaning methods (Cremonesi 2011; Daudin-Schotte et al 2013). Agar-Agar or Gellan-Gum hard gels have been utilized in order to remove dirty or proteinaceous layers by adding specific enzymatic solutions in the gels. The enzymatic cleaning has been performed at room temperature (20-23°C); the removal (total/partial) has been obtained after 10 minutes of application (Barresi et al 2015). Instead, on unvarnished and water sensitive paintings, the RCE-dry cleaning method (Rijksdienst voor het Cultureel Erfgoed- Netherland Institute for Cultural Heritage) have been applied following ad hoc protocols (Giordano et al 2014; Daudin-Schotte et al 2013).