title: Potential of Live Spirulina platensis on Biosorption of Hexavalent Chromium and Its Conversion to Trivalent Chromium.
abstract: Microalga biomass has been described worldwide according their capacity to realize biosorption of toxic metals. Chromium is one of the most toxic metals that could contaminate superficial and underground water. Considering the importance of Spirulina biomass in production of supplements for humans and for animal feed we assessed the biosorption of hexavalent chromium by living Spirulina platensis and its capacity to convert hexavalent chromium to trivalent chromium, less toxic, through its metabolism during growth. The active biomass was grown in Zarrouk medium diluted to 50% with distilled water, keeping the experiments under controlled conditions of aeration, temperature of 30°C and lighting of 1,800 lux. Hexavalent chromium was added using a potassium dichromate solution in fed-batch mode with the aim of evaluate the effect of several additions contaminant in the kinetic parameters of the culture. Cell growth was affected by the presence of chromium added at the beginning of cultures, and the best growth rates were obtained at lower metal concentrations in the medium. The biomass removed until 65.2% of hexavalent chromium added to the media, being 90.4% converted into trivalent chromium in the media and 9.6% retained in the biomass as trivalent chromium (0.931 mg.g(-1)).
authors.affiliation: a University of Passo Fundo, Graduate Program in Civil and Environmental Engineering , Bairro São José , Passo Fundo/RS , Brazil.
authors.forename: Luciane Maria
authors.initials: LM
authors.lastname: Colla
authors.forename: Clinei
authors.initials: C
authors.lastname: Dal'Magro
authors.forename: Andreia
authors.initials: A
authors.lastname: De Rossi
authors.forename: Antônio
authors.initials: A
authors.lastname: Thomé
authors.forename: Christian Oliveira
authors.initials: CO
authors.lastname: Reinehr
authors.forename: Telma Elita
authors.initials: TE
authors.lastname: Bertolin
authors.forename: Jorge Alberto Vieira
authors.initials: JA
authors.lastname: Costa
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D018533:Biomass; D002857:Chromium / Q000378:metabolism*; D007700:Kinetics; D058086:Microalgae / Q000378:metabolism*; D053545:Spirulina / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D002857:Chromium; C074702:chromium hexavalent ion
keywords: potassium dichromate; supplements; toxic metal