Research on the Antibacterial Properties of Stone Heritage Buildings

Abstract

The disinfection of stone heritage buildings poses a major challenge in global heritage conservation. Currently, the lack of effective antibacterial agents to inhibit the growth of microorganisms on stone buildings necessitates urgent exploration of effective and green methods to eliminate fungi and bacteria colonizing the surfaces of stone heritage structures. Therefore, this study synthesized silver nanoparticles using aqueous and alcoholic extracts from four plant species and evaluated their antibacterial properties. Experimental results showed that eight types of biosynthesized silver nanoparticles, particularly those synthesized using cinnamon extract, exhibited excellent antibacterial effects against Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Aspergillus flavus. These plant-mediated silver nanoparticles were synthesized under different reaction conditions and characterized by UV spectroscopy and other techniques. The results demonstrated that silver nanoparticles synthesized with cinnamon extract, in particular, showed superior antibactrial performance against E. coli, S. aureus, A. niger, and A. flavus compared to conventional chemically synthesized silver nanoparticles and the chemical biocide benzalkonium chloride (BC). This study confirms that plant-mediated synthesis of silver nanoparticles is a feasible and green antibacterial agent for application on stone heritage buildings.