This module aims to offer an overview of the preparation techniques of bio-based products: from microbial inoculums to plant products, from the selection of the most suitable strains to their growth and optimisation of the culture conditions in relation to the target. In addition, a series of gels for bacterial applications will be described with an evaluation of the advantages and disadvantages of their use. The preparation of "micro-packs" for the application of bacteria immobilized in gels and the modulation of the treatment according to the type of artwork and material to be removed. A gallery of biocleaning and bioconsolidation case studies conducted in collaboration with restorers on canvas, frescoes, wall paintings, wooden panels, mortars, marble and stone will be illustrated.