Biofilms on limestones specimens: laboratory tests implementing a non-destructive approach

This study explores the potential protective role of subaerial biofilms (SABs) in conserving stone heritage, challenging the traditional view of microbial colonization as merely damaging. SABs, composed of microorganisms embedded in extracellular polymeric substances (EPS), may form a stabilizing barrier that reduces stone surface porosity and water permeability. The research examines the long-term effect of SABs on water dynamic under moisture stress conditions (30% RH, 25 °C). We assessed water absorption, evaporation, and visual surface changes using noninvasive techniques. Findings contribute to a growing body of evidence suggesting that SABs, under specific conditions, can serve as ecocompatible alternatives to synthetic coating to preserve cultural heritage.