After centuries of trying different techniques and using various chemicals to clean art, scientists found an eco-friendly solution that already exists in the natural world.
Bacteria were thought of as art’s greatest enemy. They are evil, microscopic monsters intent on doing damage to the delicate canvases created by the hands of great art masters throughout history. But maybe not. Scientists have learned how to use helpful bacteria to clean and restore great art from the past. Recently, the technique has been used on carvings etched by Michelangelo.
The Italian National Agency for New Technologies (ENEA) started experimenting with microorganisms. They performed a “biocleaning” on tombs in Florence, Italy created by the hands of Michelangelo to remove centuries of gunk and grime from the stone. The restored statues are just one more piece of evidence that this type of art restoration is potentially far more effective than anything ever used in the past.
It all started back in the 1990s when Giancarlo Ranalli, a microbiology expert, worked in Pisa with the Technical Commission for Restoration to examine how microorganisms damage art. He worked with a team of restorers attempting to undo the damage done to the Camposanto Monumentale, a historic cemetery full of original plaster paintings and carvings. The cemetery was heavily bombed during WWII and restoration of the site proved to be extremely difficult due to animal glues used on the artifacts in the past.
Normal methods of restoration just were not working. The chemicals traditionally used in such projects had little to no effect. Finally, someone on the project asked Ranalli a question: “Dr. Ranalli, can’t you do anything with your bugs?”
And so, Ranalli gave it a shot. He covered the frescoes that needed to be restored with organic matter. He then experimented with various “bugs” until he landed on one that did the exact thing he wanted it to do: consume all the organic material, leaving the stone beneath it untouched. The “bugs” accomplished what decades of restoration attempts had failed at.
There is an entire world of bacteria out there to explore. Ranalli successfully used Pseudomonas stutzeri, strain A29, to clean away animal glue. To determine which bacteria can get a restoration job done, a microscopic Hunger Games is carried out in true dramatic fashion.
All the potential bacteria candidates are placed together in an environment where they compete for a single source of food. The food source is the target contaminant they will ultimately be tasked with removing. Whichever bacteria win this fight for the food source and learn how to use it to fuel and fed themselves will become cleaning microorganisms once they are thoroughly vetted and tested to ensure that they will not spread beyond the specific art in question, won’t infect humans and won’t cause damage to materials that should be preserved.
The method works. A team of restorers in Spain was charged with removing centuries of animal glue, left over from previous restorations, from the glorious Santos Juanes Church. They decided to try Ranalli’s miracle bug, the animal glue-devouring Pseudomonas, to remove the black film of age from the interior of the church. Centuries of dirt were eaten away by the bacteria to reveal glorious details that were covered up before.
So when faced by the tombs of the Medici Chanel in Florence, restorers turned to Giancarlo Ranalli for help. You know, the “bug” guy. The tombs were tricky indeed. Full of actual human remains, the tombs also have gorgeous marble statues carved by Michelangelo. Traditional methods would not work. Ranalli’s bacteria did.
Silvia Borghini is the conservator at the National Roman Museum. She said that bacteria has really gotten a bad rap over the years because it’s associated with infection. However, it offers up a lot of benefits as well.
“Only a very small number of bacteria are pathogens,” Borghini told CNN. “More than 95% of bacteria are not harmful to humans.”
She recently used bacteria-laden gel on the statues in the garden at the National Roman Museum, meticulously applying the material to the marble with a toothbrush. She says the bacteria is “easy to apply and afterwards, the artifacts stay clean.”
“It doesn’t harm the environment, it’s not toxic for us [humans] or the flora in the garden. It’s perfect,” Borghini said of the bacteria.
It’s a marriage of science and art that could truly change the way great works are restored and preserved in the future. This unique biotechnology could solve many problems that chemical solutions have not been able to effectively address.
And best of all, it’s organic. The bacteria do their thing and then they’re removed, leaving nothing behind but restored art. It is truly a fascinating example of what is possible when the power of the natural world is harnessed.
Lead image via Pexels