What does microbiology have to do with the restoration and conservation of our cultural heritage? Well, a lot, as Raúl Rivas teaches us in this new edition of Ciencia en la Calle.
Raúl is a professor and researcher in the Microbial Interactions Group of the Department of Microbiology and Genetics of the University of Salamanca. In addition, he loves to publicize his work, and has recently written a very entertaining book called ‘The Curse of Tutankhamun and Other Stories of Microbiology’.
One of the most active lines of work of his team focuses on the search for microorganisms capable of inducing carbonate precipitation as a result of their metabolic activity. These bacteria, which live naturally in stone, can be used to close cracks and prevent the deterioration of monuments and other buildings , and the results are promising, since the microorganisms do not remain only on the surface, but also penetrate into the rock and they manage to close pores and give the stone a lot of consistency.
Alternative to other methods of heritage restoration
Calcifying bacteria appear to be much more effective than other commonly used restoration methods. For example, certain organic treatments that are often applied to the rock contribute to environmental pollution, while other methods that use saturated solutions of calcium hydroxide have the problem of poor penetration into the rock.
We are talking about an incipient field of research, but very promising, and more and more teams are working on it. For example, a study published in 2017 in the journal Nature Communications by a team from the University of Granada demonstrated the effectiveness of the method in a test carried out at the Monastery of San Jerónimo in this same city. The researchers extracted the bacteria from the same stones of the monument, cultivated them and inoculated them again, obtaining a very effective hybrid cement , composed of bacterial calcium carbonate and other organic compounds derived from bacterial activity.
Beyond the restoration of cultural heritage, carbonate precipitating bacteria have enormous biotechnological potential. As Raúl explains to us in the video, biocements and biopavements capable of, under the right conditions, recover on their own could be developed.
Science on the Street is a project carried out in collaboration with the Scientific Culture Unit of the University of Salamanca. Our goal is to get scientists out of the lab and into the outside world so they can tell us what they do. We will be with them in the bar, in the gym, in the pool … even in an airport!
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