Unveiling the microbiome on building materials in the coastal city of Izola

Microorganisms are ubiquitous in our environment; some of them cause deterioration of building materials, while others offer their protection. Understanding the diversity and functionality of these microorganisms is crucial for the research and development of bioinspired solutions to improve the durability and performance of building materials. As part of the ARCHI-SKIN project, environmental sampling was conducted in Izola with public engagement to collect diverse microbial samples. Three locations (Sports Ground Livade Jagodje, San Simon Bay, and the Old Town of Izola) were strategically selected for swabbing different surfaces and collecting air samples. The aim of this work is to identify naturally occurring microorganisms, specifi cally fungi and bacteria, in these environments. Samples were collected using a wet-swab technique on both porous materials (wood, concrete, stone, brick) and non-porous materials (metal, plastic) at each location. The swabs were smeared on four different media types (MEACh, MEA, DG18, and LB) and incubated at 25°C. Further, 100 L of air was fi ltered onto the mentioned agar media at each location. After one week, photographs of the growth on petri dishes were taken, and representative fungal and bacterial cultures were purifi ed for further analysis and identifi cation. The results revealed a high microbial diversity on all selected material surfaces and in the air. The collection of isolates included various bacterial species, a broad spectrum of yeasts, including Aureobasidium spp., and fi lamentous fungi, including Cladosporium, Penicillium, and Alternaria spp., commonly found in nature. These fi ndings highlight the rich microbial diversity surrounding us and emphasise the potential for utilising naturally occurring microorganisms in bioinspired approaches to more sustainable architecture.