Arsenic and Cadmium Bioremediation by Antarctic Bacteria Capable of Biosynthesizing CdS Fluorescent Nanoparticles

DANIEL A. GLATSTEIN; NICOLÁS BRUNA; CARLA GALLARDO-BENAVENTE; DENISSE BRAVO; CARRO PÉREZ MAGALÍ EVELÍN; FRANCO M. FRANCISCA; JOSÉ M. PÉREZ-DONOSO

JOURNAL OF ENVIRONMENTAL ENGINEERING

ASCE-AMER SOC CIVIL ENGINEERS

Lugar: Reston, Virginia; Año: 2017 vol. 3 p. 1 - 7

0733-9372

Use of microorganisms in contaminated water remediation is one of the most studied processes of recent years. The recovery ofmetal contaminants by converting them into high-value nanomaterials represents a scarcely explored topic with high potential economicimpact. In this work, the authors determine the capacity to remove As and Cd from aqueous solutions by Antarctic bacteria previouslyreported as capable of biosynthesizing CdS fluorescent nanoparticles (NPs) at low temperatures. Bacterial characteristics favoring metalbioremediation, such as As and Cd resistance as well as high biofilm formation and metal removal (kinetic/sorption tests), were determinedin Antarctic strains. In addition, the effect of As on the biosynthesis of CdS fluorescent NPs [quantum dots (QDs)] was evaluated. Thepresence of As inhibits the biosynthesis of CdS QDs by Antarctic bacteria. Arsenic inhibition does not involve the disruption of theCd nanostructure or a decrease in H2S levels produced by cells, suggesting that As inhibits CdS biosynthesis by avoiding the interactionof Cd2þ with S2− required to produce the nanocrystal. Obtained results have significant consequences for the development of metalbioremediation strategies aimed at removing environmental heavy metals through the generation of NPs.