Bioreduction of Iron and Biosorption of Heavy Metals (Ni²⁺, Co²⁺, Pb²⁺) by a Novel Environmental Bacterium, Tabrizicola aquatica RCRI19^T

Article type: Research Article

Authors: Tarhriz, Vahideh^a | Akbari, Zahra^b | Dilmaghani, Azita^{b; c; *} | Hamidi, Adel^d | Hejazi, Mohammad Amin^e | Hejazi, Mohammad Saeid^{a; b}

Affiliations: [a] Molecular Medicine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran | [b] Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran | [c] Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran | [d] Young Researchers and Elite Club, Karaj Branch, Islamic Azad University, Karaj, Iran | [e] Agricultural Biotechnology Research Institute of Iran (ABRII) for Northwest and West of Iran, Tabriz, Iran

Correspondence: [*] Corresponding Author. dilmaghani.a@gmail.com

Abstract: Environmental bacteria have an important role in the removal and improvement of metals from polluted area. Metal–microbe interactions as a form of detoxification of metal have been developed. In this study, we investigated the ability of Tabrizicola aquatica RCRI19T, a novel environmental bacterium isolated from deepwater from Qurugöl Lake nearby Tabriz city, Iran, to Fe(III)-reduction as an electron acceptor in minimal essential elements condition. Subsequently, bioabsorption behaviour of heavy metals (Ni2+, Co2+, pb2+) by strain RCRI19T has been demonstrated. Our results showed that strain RCRI19T can reduce 20mM ferric-citrate particularly in anaerobic condition, and a positive correlation was observed between bacterial growth and iron (II) production. Owing to its iron reduction rate, T. aquatica RCRI19T may contribute to iron mineral transformation and element cycling in deepwater of the lake. We further observed that the dead biomass of strain RCRI19T absorbs of heavy metals (Ni2+, Co2+ and Pb2+) from aqueous solution. The optimum conditions of biosorption are in pH = 4 for Ni2+, Pb2+ and pH = 5 for Co2+. The equilibrium experimental data fitted both of Freundlich and Langmuir isotherms and displayed monolayer adsorption. Two kinetic models, namely pseudo-first-order and pseudo-second-order were used to describe the kinetics of heavy metal ion biosorption on T. aquatica. Pseudo second order was the best of the other kinetic.

Keywords: Tabrizicola aquatica RCRI19^T, Fe(III)-reduction, bioabsorption of heavy metals

DOI: 10.3233/AJW190035

Journal: Asian Journal of Water, Environment and Pollution, vol. 16, no. 3, pp. 73-81, 2019