Modelling growth of, and removal of Zn and Hg by a wild microalgal consortium

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Cristina M. Monteiro (Author) Other; Teresa R. S. Brandão (Author) Other; Paula M. L. Castro (Author) Other; F. Xavier Malcata (Author) FEUP

Journal

Title: Applied Microbiology and Biotechnology

Vol. 94 No. 1

Pages: 91-100

ISSN: 0175-7598

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 1 Citation

ISI Web of Science

Scopus - 1 Citation

Scientific classification

FOS: Engineering and technology

Other information

Authenticus ID: P-002-BS6

DOI: 10.1007/s00253-011-3826-x

Abstract (EN): Microorganisms isolated from sites contaminated with heavy metals usually possess a higher removal capacity than strains from regular cultures. Heavy metal-containing soil samples from an industrial dumpsite in Northern Portugal were accordingly collected; following enrichment under metal stress, a consortium of wild microalgae was obtained. Their ability to grow in the presence of, and their capacity to recover heavy metals was comprehensively studied; the datasets thus generated were fitted to by a combined model of biomass growth and metal uptake, derived from first principles. After exposure to 15 and 25 mg/L Zn2+ for 6 days, the microalgal consortium reached similar, or higher cell density than the control; however, under 50 and 65 mg/L Zn2+, 71% to 84% inhibition was observed. Growth in the presence of Hg2+ was significantly inhibited, even at a concentration as low as 25 mu g/L, and 90% inhibition was observed above 100 mu g/L. The maximum amount of Zn2+ removed was 21.3 mg/L, upon exposure to 25 mg/L for 6 day, whereas the maximum removal of Hg2+ was 335 mu g/L, upon 6 day in the presence of 350 mu g/L. The aforementioned mechanistic model was built upon Monod assumptions (including heavy metal inhibition), coupled with Leudeking-Piret relationships between the rates of biomass growth and metal removal. The overall fits were good under all experimental conditions tested, thus conveying a useful tool for rational optimisation of microalga-mediated bioremediation.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10