Development and modeling of the effective bioactive poultices for reducing the nitrate content in building materials Snezana Vucetic a,⇑ , Jonjaua Ranogajec a , Sinisa Markov a , Ana Vidakovic a , Helena Hirsenberger b , Oskar Bera a a University of Novi Sad, Faculty of Technology, Bul. Cara Lazara 1, 21000 Novi Sad, Serbia b University of Novi Sad, Faculty of Technical Science, Trg Dositeja Obradovic ´a 1, 21000 Novi Sad, Serbia highlights  Reducing nitrate salt contents in the affected objects.  Development and modeling of the effective bioactive poultices.  Poultices provide a suitable microenvironment for the P. stutzeri metabolic activity.  Used an ANN model in order to reduce the time of experiments and the cost. graphical abstract article info Article history: Received 14 November 2016 Received in revised form 23 February 2017 Accepted 9 March 2017 Keywords: Nitrate content reduction Bioactive systems Building materials ANN model abstract Two types of poultices, selected after the investigation of a number of raw materials, whose combination showed desired activities, were combined with a Pseudomonas stutzeri suspension to yield effective bioactive poultices for reducing the nitrate content in the model bricks. The efficiency was studied as a function of the application mode, porosity of the brick models, bacterial cells viability, and depth of the models. The outcome of the study is an ANN model with a high correlation coefficient, emphasizing that the depth of the bricks is the most influential (negative) factor considering the denitration efficiency. Ó 2017 Elsevier Ltd. All rights reserved. 1. Introduction Building materials are prone to undergo complex deterioration processes of chemical, physical, and biological transformations caused by atmospheric factors [1]. A primary result of these pro- cesses is the formation of soluble salts, which is most pronounced in the case of porous building materials in both contemporary and historical structures [2,3]. Salt-induced deterioration is a natural process, and therefore it cannot be fully prevented but only slowed down by reducing the salt content in the affected objects. Attempts to control the environmental conditions could be a good solution to reduce the incidence of crystallization/dissolution cycles of soluble salts by minimizing their destructive effects on the built-in materials. However, to achieve and maintain appropriate climatic conditions http://dx.doi.org/10.1016/j.conbuildmat.2017.03.075 0950-0618/Ó 2017 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: snezanap@uns.ac.rs (S. Vucetic). Construction and Building Materials 142 (2017) 506–513 Contents lists available at ScienceDirect Construction and Building Materials journal homepage: www.elsevier.com/locate/conbuildmat