Please cite this article in press as: A.T. Fazio, et al., Towards a better comprehension of biodeterioration in earthen architecture: Study of fungi colonisation on historic wall surfaces in Brazil, Journal of Cultural Heritage (2015), http://dx.doi.org/10.1016/j.culher.2015.04.001 ARTICLE IN PRESS G Model CULHER-2953; No. of Pages 5 Journal of Cultural Heritage xxx (2015) xxx–xxx Available online at ScienceDirect www.sciencedirect.com Case study Towards a better comprehension of biodeterioration in earthen architecture: Study of fungi colonisation on historic wall surfaces in Brazil Alejandra T. Fazio a,∗ , Andrea Cavicchioli b,1 , Daysi S.A. Penna b,2 , Felipe S. Chambergo b,2 , Dalva L.A. de Faria a,3 a Laboratorio de Espectroscopia Molecular, Instituto de Química, Universidade de São Paulo, Av. Professor Lineu Prestes, 748, 05508-000 São Paulo (SP), Brazil b Escola das Artes, Ciencias e Humanidades, Universidade de São Paulo, Av. Arlindo Bettio, 1000, 03828-000 São Paulo (SP), Brazil a r t i c l e i n f o Article history: Received 30 September 2014 Accepted 7 April 2015 Available online xxx Keywords: Biodeterioration Fungi Earthen architecture Coffee cycle Brazil a b s t r a c t This study was aimed to describe fungal communities found in biofilms growing on earthen walls (rammed earth, wattle-and-daub and adobe) of rural and semi-urban historical buildings representa- tive of the first phase of the Brazilian coffee cycle (1820–1880), in the upper basin of the Paraiba do Sul river, São Paulo State. The relationship between substrates and such surface-associated microbial com- munities was also investigated. Fungal biodiversity was significantly higher in rammed earth with respect to the other two techniques. Granulometric analysis showed that rammed earth also contained a higher percentage of coarse soil fraction which is likely to favour the accumulation of water and organic mat- ter. Cellulolytic activity tested positive for the majority of fungi and acidification test showed that fungi exhibit elevated acidifying capacity suggesting that biodeterioration may occur through acid metabolites. © 2015 Elsevier Masson SAS. All rights reserved. 1. Introduction and research aims Fungi biodeterioration is one of the most important decay mech- anisms acting in the progressive loss in aesthetical and functional properties of building materials on both organic and inorganic sub- strates [1]. The main aggression pathways include: • degradation of organic and mineral substances to obtain nutri- ents and extract energy; • production of molecules, such as acids or complexing agents, mainly aiming at abating the cohesion of the substrate; • excretion of metabolic waste, which can cause aesthetically undesirable effects [2]. ∗ Corresponding author. Tel.: +55 11 30913853. E-mail addresses: fazio.alejandra@gmail.com (A.T. Fazio), andrecav@usp.br (A. Cavicchioli), daysi andrade@hotmail.com (D.S.A. Penna), fscha@usp.br (F.S. Chambergo), dlafaria@iq.usp.br (D.L.A. de Faria). 1 Tel.: +55 11 30911058. 2 Tel.: +55 11 30918922. 3 Tel.: +55 11 30913853. In Brazil, earthen techniques like rammed earth (taipa de pilão), wattle-and-daub (pau-a-pique) and adobe predominated until the late XIX century [3,4], before the introduction of brick on a large- scale. Earthen architecture was almost the exclusive choice in building practice in rural Rio de Janeiro and São Paulo states dur- ing the first phase of the so-called coffee cycle (approximately 1820–1880). This was a time of extraordinary economic growth based on the large-scale production of coffee grains along the upper basin of the river Paraiba do Sul (Fig. 1), resulting in a consider- able ensemble of elegant country houses and a few small urban agglomerates (Fig. 2). This exceptional heritage is today subjected to a number of vul- nerability factors that create environments propitious to all kinds of biological activity. This state of things reinforces the need of accurately identifying decay agents, assessing their mechanisms of action and tailoring ad hoc conservation strategies, also in the light of the exacerbation of climate conditions in the forthcoming decades. The present work – the first study on biodeterioration of earthen walls – reports the preliminary results on fungi presence in biofilms formed on uncapped earthen walls of selected historic buildings of the study area and discusses the correlations between the sort of deterioration that they are causing and the features of the different constructive techniques. http://dx.doi.org/10.1016/j.culher.2015.04.001 1296-2074/© 2015 Elsevier Masson SAS. All rights reserved.