Search For Efficient Chitosan-Based Fungicides To Protect The 15th-16th Centuries Tempera Painting In Exhibits From The State Tretyakov Gallery

Growth inhibition by chitosans (with molecular weight 6, 12, 18, 25 and 45 kDa) was demonstrated for 10 filamentous fungi belonging to the families Aspergillaceae, Cladosporiacea, Pleosporaceae, Cordycipitaceae and Microascaceae which are responsible for biodeterioration of tempera paintings and are the dominant members of microbiome from Paintings of Ancient Rus Halls, State Tretyakov Gallery, Russia. The greatest effect was achieved at 2% chitosan in agar medium; its antifungal activity increased in the row: 6-12-18-25 kDa. Chitosans with a molecular weights of 25 and 45 kDa inhibited fungal growth to the same degree. Representatives of Cladosporiaceae and Sordariomycetes (Cordycipitaceae and Microascaceae) showed the greatest sensitivity to chitosan. Some Aspergillaceae were found to exhibit elevated resistance. Investigation of antifungal activity of chitosans incorporated into tempera materials to assess their possible application as art objects antiseptics will be the goal of our further research.