Optimization of culture conditions for growth associated Cr(VI) removal by Wickerhamomyces anomalus M10

FERNANDEZ, PABLO M; CRUZ, ELÍAS L.; VIÑARTA, SILVANA C; FIGUEROA, LUCÍA I. C.

BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY

SPRINGER

Lugar: Berlin; Año: 2015

0007-4861

Chromate-resistant microorganisms with the ability of reducing toxic Cr(VI) to less toxic Cr(III), are candidates for bioremediation. An alternative culture medium to remove Cr(VI) using Wickerhamomyces anomalus M10 was optimized. Using Plackett-Burman design, was possible to determine that sucrose, K2HPO4 and inoculum size had significant effect on chromate removal at 24 h. Concentrations of these significant factors were adjusted using a Complete Factorial design. In this case, only K2HPO4 potassium hydrogen phosphate effect was significant at 12 h of culture, with greater Cr(VI) removal at low concentration (1.2 g L-1). Validation of optimized medium was realized at fermenter scale. Optimal culture conditions for complete removal of Cr(VI) (1 mM) were 400 rpm agitation and air flow of 1 vvm. Moreover, W. anomalus M10 completely removed consecutive pulses added of Cr(VI) (1 mM). These results show interesting characteristics from the standpoint of biotechnology because the development of a future remediation process using W. anomalus M10 can represent an efficient and highly profitable technology for removing the toxic form of Cr.