Improved methodology for bioremoval of black crusts on historical stone artworks by use of sulfate-reducing bacteria.
An improved methodology to remove black crusts from stone by using Desulfovibrio vulgaris subsp. vulgaris ATCC 29579, a sulfate-reducing bacterium, is presented. The strain removed 98% of the sulfates of the crust in a 45-h treatment. Precipitation of black iron sulfide was avoided using filtration of a medium devoid of iron. Among three cell carriers, Carbogel proved to be superior to both sepiolite and Hydrobiogel-97, as it allowed an easy application of the bacteria, kept the system in a state where microbial activity was maintained, and allowed easy removal of the cells after the treatment.
Cappitelli
Francesca
F
Dipartimento di Scienze e Tecnologie Alimentari e Microbiologiche, Università degli Studi di Milano, Via Celoria 2, 20133 Milan, Italy. francesca.cappitelli@unimi.it.
Zanardini
Elisabetta
E
Ranalli
Giancarlo
G
Mello
Emilio
E
Daffonchio
Daniele
D
Sorlini
Claudia
C