Evaluation of the antifungal efficiency of biocides currently applied in the Coimbra UNESCO area limestone monuments

Abstract

The application of biocides to control microbial proliferation in stone materials is nowadays a rather common practice. In the Coimbra´s UNESCO World heritage monuments, biocide treatments rely on the application of Biotin T and Preventol R80. However, the application of these formulations often occurs without the complete knowledge of microbial communities’ susceptibility to their application. The aim of this study was to evaluate the efficiency of these compounds and compare them with a commercial version of Ocimum basilicum essential oil, against various fungal species present in these areas. Through the application of in vitro antifungal activity assays, we were able to verify that, in general, Biotin T rather than Preventol R80 was more efficient against all tested fungi. In addition, the commercial version of the Ocimum basilicum essential oil also exhibited good results and might be an alternative option to be taken into consideration in future interventions in these monuments.