Table 3.

Overview of different methodologies where microbial calcite has been deposited as a layer on surface of stone.

Experimental methods	Application procedure			Authors
Inoculum	Bacteria	Nutrients	Evaluation procedures
Culture in exponential phase: 107 to 109 cells/ ml	Spraying	Spraying (5 times)	Water absorption, SEM analysis, surface roughness, colorimetery and plate count	Calcite bioconcept Le Metayer-Levrel et al., 1999
Overnight culture 106 cells cm−2	Brushing on water saturated specimens	Wetting every day for 15 days	Water absorption, colorimeteric measurements, stone cohesion	Tiano et al., 1999
2% Inoculums	Immersion in growing bacterial culture (shaking or stationary conditions) for 30 days		Stone cohesion, weight increase, XRD and SEM analysis, porosimetery analysis	Rodriguez-Navarro et al., 2003
1% Inoculums	Immersion in growing bacterial culture (intermediate wetting) for 28 days		Water absorption, SEM analysis	Dick et al., 2006
108 cells ml−1	Spraying	In Carbogel	Water absorption and drying due to evaporation	May, 2005
n.d.*	n.d.*	Immersion in test solution or spraying (in situ) tests	Water absorption, colorimeteric measurements, stone cohesion, staining of newly formed calcite with Alizarin Red S and Calcein	Tiano et al., 2006
Overnight culture 107 to 109 cells ml−1	Immersion for 1 day	Immersion for 4 days	Weight increase, water absorption, gas permeability, chloride migration, carbonation, freezing and thawing, SEM and XRD analysis	De Muynck et al., 2008a

^*n.d., not defined.