Bioremoval of Ni and Cd in the presence of diethylketone by fungi and by bacteria - A comparative study

• Autor(a) principal: Costa, Filomena
• Data de Publicação: 2017
• Outros Autores: Tavares, T.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Texto Completo: https://hdl.handle.net/1822/44857
• topic: Bacteria; Cadmium; Diethylketone; Fungi; Kinetics; Nickel; Science & Technology

Two fungi (Alternaria sp. and Penicillium sp.) and one gram-positive bacterium (Streptococcus equisimilis) were used to remove Ni and Cd from aqueous solutions in the presence of diethylketone. Individual toxicity assays were performed at an initial stage to evaluate the xenobiotic impact of the initial concentration of those metals on the growth of the microorganisms and allowed to infer that the growth of S. equisimilis is negatively affected by both metals, whereas the growth of both fungi is positively stimulated by the presence of Ni and inhibited by Cd (>40 mg/L). Within the group of microorganisms tested, S. equisimilis presented higher removal efficiency (%) and uptake. In a second stage, biosorption assays were performed using aqueous solutions containing Ni, Cd and diethylketone (mixed solutions) and aimed to infer about the overall effect of the initial metal concentrations on the growth and on the sorption capacity of the microorganisms, as well as to evaluate the interaction between the sorbent matrices. It was demonstrated that despite the mixed solution exert a negative effect on the removal process and on the growth of the three microbial cultures, the system is able to decontaminate aqueous solutions with high concentrations of Ni, Cd and diethylketone.