Cellulolytic activity of biodeteriogenic Aspergillus sp. strains

Abstract

During history, wooden buildings exposed to various agents, either biotic or abiotic, have suffered damage under the influence of living organisms like fungi. The main strategy for degrading wood polymers- cellulose, hemicellulose and lignin is by secreting enzymes that break down the main constituents through lysis.
This study investigates the enzymatic activity of various Aspergillus sp. strains identified on the walls of Boz wooden Church in Hunedoara County, Romania, by analysing the influence of different parameters on the production of the cellulolytic enzymes and confirming the presence of a cellulase coding gene fragment. The research primarily examines the total cellulase activity of three Aspergillus species—Aspergillus niger, Aspergillus nidulans and Aspergillus sclerotiorum—isolated from medieval wooden churches in Transylvania, Romania. Variations of several parameters was analysed, such as the incubation time, the influence of incubation temperature on enzymatic digestion, influence of citrate buffer pH, influence of substrate concentration. Additionally, a phylogenetic analysis has been performed based on similarities between the Internal Transcribed Spacer (ITS) regions for the investigated strains.