Metabolic activity of moulds as a factor of building materials biodegradation

This paper presents the effect of building materials on the growth and metabolic activity of moulds. In cultures of Aspergillus and Penicillium moulds grown on a model medium with the addition of building materials, the biomass of mycelium, its cellular components--glucan, chitin, ergosterol and the spectrum of enzymes and organic acids produced in the medium were investigated. It was found that on the medium with wallpaper moulds produced more biomass and extracellular enzymes, mainly glycolytic ones. On medium with mortar the growth of mycelium was impeded, production of biomass was 60% smaller, the quantity of chitin, glucan and ergosterol decreased 13-41%, and the activity of most enzymes was reduced; however the moulds intensively produced organic acids: malic, succinic and oxalic acid. The largest acid production activity was found in medium with addition of mortar; moulds produced the greatest variety of acids and in greater quantities than in the control medium. Metabolic activity of the moulds depends on the type of building material, and may lead to biodeterioration of these materials.