Disinfection of water and wastewater by biosynthesized magnetite and zerovalent iron nanoparticles via NAP-NAR enzymes of Proteus mirabilis 10B

• Published in: Environmental science and pollution research international Vol. 26; no. 23; pp. 23661 - 23678
• Main Authors: Zaki, Sahar A., Eltarahony, Marwa Moustafa, Abd-El-Haleem, Desouky A.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2019; Springer Nature B.V
• Subjects: Agricultural wastes; Algae; Algal growth; Algicides; Anaerobic conditions; Aquatic Pollution; Arid regions; Atmospheric Protection/Air Quality Control/Air Pollution; Disinfection; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Enzymes; Exploitation; Iron; Magnetite; Microorganisms; Municipal wastewater; Nanoparticles; Photomicrographs; Proteus mirabilis; Quality standards; Reductases; Research Article; Salt mines; Semi arid areas; Spectroscopy; Stability analysis; Surface plasmon resonance; Synthesis; Waste Water Technology; Wastewater; Water analysis; Water Management; Water Pollution Control; Water quality; Water quality standards; Water sampling; Water shortages; Water treatment; Zeta potential; Disinfection; Magnetite iron nanoparticles; Antagonistic activity; Nitrate reductase; Wastewater treatment
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-019-05479-2

Disinfection of water and wastewater strongly contributes to solving the problem of water shortage in arid/semi-arid areas; cheap and ecofriendly approaches have to be used to meet water quality standards. In the present study, a green synthesis of iron nanoparticles (INPs) under aerobic and anaerobic conditions via nitrate reductases (NAP/NAR) enzymes produced by Proteus mirabilis strain 10B were employed for this target. The biosynthesized INPs were characterized; UV-Vis spectroscopy revealed surface plasmon resonance at 410 (aerobic) and 265 nm (anaerobic). XRD indicated crystalline magnetite ((MNPs) aerobically synthesized) and zerovalent INPs (ZVINPs anaerobically synthesized). EDX demonstrated strong iron signal with atomic percentages 73.3% (MNPs) and 61.7% (ZVINPs). TEM micrographs illustrated tiny, spherical, periplasmic MNPs (1.44–1.92 nm) and cytoplasmic ZVINPs with 11.7–60.8 nm. Zeta potential recorded − 31.8 mV (ZVINPs) and − 66.4 mV (MNPs) affirming colloidal stability. Moreover, the disinfection power of INPs was evaluated for standards organisms and real water (fresh, sea and salt mine) and wastewater (municipal, agricultural and industrial) samples. The results reported that INPs displayed higher antagonistic effect than iron precursor, 700 and 850 μg/mL of MNPs and ZVINPs, respectively, was sufficient to show a drastic algicidal effect on algal growth. Both types of INPs demonstrated obvious dose-dependent antibiofilm efficiency. Due to their smaller size, MNPs were more efficient than ZVINPs at the suppression of microbial growth in all examined water samples. Overall, MNPs showed superior antagonistic activity, which promotes their exploitation in enhancing water/wastewater quality.