Biodeterioration of stone monuments: Studies on the influence of bioreceptivity on cyanobacterial biofilm growth and on the biocidal efficacy of essential oils in natural hydrogel.

Autor: Gabriele F; Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio - Coppito, I-67100, L'Aquila, Italy. Electronic address: francesco.gabriele@univaq.it., Ranaldi R; LBA-Laboratory of Biology of Algae, Department of Biology, University of Rome 'Tor Vergata', Via Cracovia 1, I-00133, Rome, Italy; PhD program in Evolutionary Biology and Ecology, Dept. of Biology, University of Rome 'Tor Vergata', Rome, Italy. Electronic address: roberta.ranaldi@alumni.uniroma2.eu., Bruno L; LBA-Laboratory of Biology of Algae, Department of Biology, University of Rome 'Tor Vergata', Via Cracovia 1, I-00133, Rome, Italy. Electronic address: laura.bruno@uniroma2.it., Casieri C; Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio - Coppito, I-67100, L'Aquila, Italy. Electronic address: cinzia.casieri@aquila.infn.it., Rugnini L; LBA-Laboratory of Biology of Algae, Department of Biology, University of Rome 'Tor Vergata', Via Cracovia 1, I-00133, Rome, Italy. Electronic address: Lorenza.Rugnini@uniroma2.it., Spreti N; Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio - Coppito, I-67100, L'Aquila, Italy. Electronic address: nicoletta.spreti@univaq.it.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2023 Apr 20; Vol. 870, pp. 161901. Date of Electronic Publication: 2023 Feb 02.
DOI: 10.1016/j.scitotenv.2023.161901
Abstrakt: An important field of research is devoted to the development of innovative, sustainable, and safe methodologies to counteract biodeterioration of stone monuments due to the growth of microbial communities. However, besides the biocide's efficacy, it is crucial to consider the features of substrates on which biocides must be applied, to define the so-called bioreceptivity of the lithic faces. In this research five different lithotypes, namely Lecce stone, Travertine, Peperino, Serena stone, and Granite, have been used as substrates for the growth of cyanobacterial biofilms. Open porosity, hygroscopic properties, and roughness parameters have been investigated for each lithotype and correlated to the photosynthetic yields of the biofilms colonizing the different stones to propose an easy method to estimate stone bioreceptivity. Different levels of coverage of the stone surfaces have been accomplished in relation to the typology of lithotypes. To develop innovative restoration methodologies against biodeterioration of stone monuments, a hydrogel-biocide system has been optimized by using a polysaccharide dispersion as a matrix where to embed T. vulgaris essential oil (at 0.25 % or 0.1 %) or its main component thymol (at 0.18 % or 0.07 %). The efficacy and the effect of the innovative biocide have been evaluated combining microscopy, photosynthetic measurements, and colorimetric analyses and both the biocides (with T. vulgaris EO or thymol) showed to be highly effective against the cyanobacterial biofilms for at least six months from the treatment without inducing any significant alteration to the lithic surfaces. The efficacy of thymol alone allows to treat colonized surfaces with a single active ingredient, or at least a mixture thereof, much cheaper and reproducible. The results obtained in this work pave the way to develop a sustainable cleaning protocol to counteract the biodeterioration of stone monuments or historic buildings induced by the presence of phototrophic biofilms that endangered their conservation.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
Externí odkaz: