Phenol degradation and heavy metal tolerance of Antarctic yeasts

FERNANDEZ P; MARTORELL MM; BLASER G; RUBERTO L; FIGUEROA L; MAC CORMACK W.P

EXTREMOPHILES

SPRINGER TOKYO

Lugar: Tokyo; Año: 2017 vol. 21 p. 445 - 447

1431-0651

In cold environments, biodegradation oforganic pollutants and heavy metal bio-conversion requiresthe activity of cold-adapted or cold-tolerant microorganisms. In this work, the ability to utilize phenol, methanoland n-hexadecane as C source, the tolerance to diferentheavy metals and growth from 5 to 30°C were evaluatedin cold-adapted yeasts isolated from Antarctica. Fifty-ninepercent of the yeasts were classifed as psychrotolerantas they could grow in all the range of temperature tested,while the other 41% were classifed as psychrophilic asthey only grew below 25°C. In the assimilation tests, 32,78, and 13% of the yeasts could utilize phenol, n-hexadecane, and methanol as C source, respectively, but only 6%could assimilate the three C sources evaluated. In relationto heavy metals ions, 55, 68, and 80% were tolerant to1 mM of Cr(VI), Cd(II), and Cu(II), respectively. Approximately a half of the isolates tolerated all of them. Most ofthe selected yeasts belong to genera previously reported as common for Antarctic soils, but several other genera werealso isolated, which contribute to the knowledge of thiscold environment mycodiversity. The tolerance to heavymetals of the phenol-degrading cold-adapted yeasts illustrated that the strains could be valuable as inoculant forcold wastewater treatment in extremely cold environments.