Effect of innovative bioproducts on the performance of bioformulated earthen plasters

Abstract Biotechnologies mainly based on precipitation of chemical compounds produced by microbial metabolism can be used as biotreatment or bioformulation construction materials. Bioformulation cement-based materials has been a common research practice, though its application to earthen-based building is still limited. Although earth mortars are vulnerable water damage, they nowadays often plasters new constructions but also for the retrofitting existent buildings. Their reversibility and compatibility with old substrates make them interesting conservation interventions, namely when applied protect archaeological structures sacrificial renders. In this study, an innovative bioproduct cellular extracts Escherichia coli, cultured in Lysogeny broth (LB) medium supplemented iron, was developed component mortars’ bioformulation. The coli strain classified not hazardous. An additional mortar bioformulated LB mixing liquid tested assess influence culture medium. iron supplement chosen infer about oxide biomineral formation, less toxic mineral than calcite, since no by-products produced, minerals have longer lifetime compared calcite crystals. Bioformulated presented very distinct porous structure, significant decrease mechanical properties. Nevertheless, showed thermal conductivity, slight consolidative effect, vulnerability towards water. Apart from possible use air entraining agents, obtained results show interest further studies nontoxic iron-based bioproducts earthen optimization.