NAP enzyme recruitment in simultaneous bioremediation and nanoparticles synthesis

Abstract

Graphical abstractOur study aims to exploit the denitrifying bacteria MMT and its NAP enzyme in dual missions, nitrate removal from wastewater and nanoparticles synthesis. Therefore, the crud NAP enzyme was characterized and immobilized by entrapment technique for aforementioned application. To the best of author knowledge, the immobilization for denitrifying bacteria and NAP enzyme for simultaneous bioremediation and bionanoparticles synthesis was not studied previously.

Study on the Antagonistic Potential of Biosynthesized Hematite Nanoparticles During Water and Wastewater Treatment

“…The biogenic HNPs (α‐Fe 2 O 3 ) were previously synthesized from Achromobacter sp. strain MMT (KT735046) and characterized by UV‐vis spectroscopy (absorption range from 400 to 464 nm), energy dispersive X‐ray (EDX) (62% of iron), X‐ray diffraction (XRD) (crystallite rhombohedral hematite), TEM (1.4–2.8 nm in size) and ζ‐potential (–42.9 mV) with polydispersity index (PDI) (0.268) following the procedure of Eltarahony et al These characterization techniques confirmed the small size, self‐stabilizing, high stability, and mono‐dispersity of biogenic HNPs without agglomeration. In the present study, the antagonistic activity and disinfection strength of HNPs were examined.…”

“…Obviously, all previous methods require surface modification for HNPs by utilizing polymers such as chitosan, polyvinylepyrrolidone (PVP), agarose, dextran, and gelatin . In the current study, the biologically synthesized HNPs seemed to be characteristic by mono‐dispersity, high stability, additive free, larger surface area by smaller size and above all self‐functionalized as investigated previously by Eltarahony et al The inhibitory mechanism of HNPs against some selected pathogens was also studied using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Additionally, the disinfection strength of HNPs in the treatment of various water (fresh, sea, and salt mine) and wastewater (municipal, agricultural, and industrial) samples from Egyptian ecosystems was determined which was not reported previously.…”

“…This result suggests that the presence of suspended solids might obstruct the way of HNPs to microbial cells. Additionally, the presence of higher concentrations of Cl − , Na + , Ca 2+ , and Mg 2+ ions in salt water could contribute to the aggregation of HNPs and consequently diminish the efficiency of the interaction process between HNPs and microbial surface …”

“…According to Gupta et al, the optical density (OD) of stained biofilm was determined at 595 nm using the plate reader (Tecan Infinite M200, Switzerland). The OD values were considered as an index of biofilm formation by sessile bacteria adhering to the surface . A more intensive antibiofilm effect was considered where a lower absorbance value was detected .…”

Nanoparticle–Plant Interactions: Two‐Way Traffic

“…They bear unique properties such as an extremely high ratio of surface‐to‐volume and specific surface area, which determine excellent chemical, optical, mechanical, and electronical properties . From the points of view of structure and chemical composition, nanomaterials are heterogeneous group of compounds, include carbonaceous materials, semiconductors, metal oxides, lipids, zero‐valent metals, quantum dots, nanopolymers, and dendrimers with different morphologies such as rods, fibers, wires, and sheets …”