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


  • João Trovão Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal https://orcid.org/0000-0002-7845-6046
  • António Portugal Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456 Coimbra, Portugal; Fitolab-Laboratory for Phytopathology, Instituto Pedro Nunes, 3030-199 Coimbra, Portugal https://orcid.org/0000-0003-1748-6345




Biodeterioration, Biotin T, Fungi, O. basilicum essential oil, Limestones, Preventol R80


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.


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Figure 2. Example of a preliminary comparative evaluation of Biotin T and Preventol R80 efficiency against Penicillium brevicompactum evaluated through the Agar disc diffusion method.




How to Cite

Trovão, J., & Portugal, A. (2023). Evaluation of the antifungal efficiency of biocides currently applied in the Coimbra UNESCO area limestone monuments. Conservar Património, 42, 7–16. https://doi.org/10.14568/cp25076




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