Duke Alessandro de Medici is leaking. Well, to be exact, his corpse, buried in his father’s tomb, which is now the Medici Chapel, is leaking bodily fluids along with other compounds accumulated over time from glue and plaster. The grime is now evident in the marble statues that adorn the area, which were created by Michelangelo:
Anna Rosa Sprocati, a biologist at the Italian National Agency for New Technologies, hand-picked from her catalog of more than 1,000 bacteria to test against the stains. They had successes and failures, with some of the bacteria eating not just the human remains, but the delicate Carrera marble, too. But the chapel's museum believed that bacteria would be more effective than harsh chemicals or abrasives.
Sprocati's all-female team picked the eight most promising bacteria and tested them on a gridded section behind the altar of the church. The ones that worked were then put on the tomb of Giuliano di Lorenzo, specifically the statues of Night and Day. The bacteria successfully cleaned Night's hair and eyes of accumulated residue.
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