Mercury removal during growth of mercury tolerant and self-aggregating Yarrowia spp.

AMB Express

Table 1 Masses, protein quantities, and Hg complexation (precipitation) of EPS extracted from the supernatants and pellets of yeast strains cultivated in media supplemented with or without HgCl₂

Strain	Hg conc in medium (μg ml⁻¹)	Cell bound EPS			Extracellular EPS
Strain	Hg conc in medium (μg ml⁻¹)	Mass^a (mg dw)	Hg chelated onto EPS (mg gdw⁻¹)	Protein in EPS (mg gdw⁻¹)	Mass^a (mgdw)	Hg chelated onto EPS (mg gdw⁻¹)	Precipitated Hg in supernatant (%)	Protein in EPS (mg gdw⁻¹)
Idd1	0	0.6	0.209	0.028	3.0	0.035	NA	0.028
	16.0	0.5	2.45	0.707	2.4	8.50	53.1	0.848
	32.0	0.7	4.50	0.752	2.9	13.1	40.8	1.90
Idd2	0	1.2	0.316	0.028	5.0	0.073	NA	0.028
	16.0	0.9	2.59	0.799	2.3	9.41	58.8	0.740
	32.0	1.1	4.46	0.897	1.4	13.8	48.1	1.39

Values represent mean of triplicate experiments
NA means not applicable because the medium was not supplemented with HgCl₂, but Hg analysis of the culture revealed Hg presence as explained in “Hg micro-precipitation due to EPS complexation with Hg” section. Growth medium (negative control) without inoculation with yeast strains lacks detectable Hg
^aMass of EPS extracted from 20 ml yeast culture (OD_{600 nm} = 1.2, approx.)