Nano-metals forming bacteria in Egypt. I. Synthesis, characterization and effect on some phytopathogenic bacteria in vitro

Abstract

Bacterial metal reducers were isolated from water samples collected from harsh condition locations in Egypt. Four selected isolates were identified as Enterococcus thailandicus, Pseudomonas putida, Marinobacter hydrocarbonoclasticus, and P. geniculata for Copper (Cu), Iron (Fe), Cobalt (Co) and Zinc (Zn) Nanoparticles (NPs) production sequentially. Nitrate reductase enzyme was assayed for bacterial isolates which demonstrated that P. putida, and M. hydrocarbonoclasticus have the maximum enzyme production. The produced NPs were characterized by using XRD, TEM, UV–VIS spectroscopy. Magnetic properties for all selected metals NPs were measured using Vibrating Sample Magnetometer (VSM) and demonstrated that FeNPs recorded the highest magnetization value. The antibacterial activity of selected metals NPs was tested against some phytopathogenic bacteria causing the following diseases: soft rot (Pectobacterium carotovorum, Enterobacter cloacae), blackleg (Pectobacterium atrosepticum and Dickeya solani), brown rot (Ralstonia solanacearum), fire blight (Erwinia amylovora) and crown gall (Agrobacterium tumefaciens). All metals NPs showed an antagonistic effect against the tested isolates, particularly, FeNPs showed the highest antibacterial activity followed by CuNPs, and ZnNPs. Due to the small size, high reactivity, and large surface area of biologically synthesized NPs, they are used as a good disinfector, and can be considered as a new and alternative approach to traditional disease management methods.

Nano-metals forming bacteria in Egypt. II. Efficacy towards biomolecules, ultrastructure, growth parameters, and eco-friendly therapeutic of soft rot/blackleg genera

“…Depending on the results obtained from our findings in the previous study [ 38 ], it proved the ability of FeNPs to act as antibacterial agents of D. solani . Thus FeNPs were chosen in this study to test the uptake in plant tissue.…”

“…Nano-metals forming bacteria E. thailandicus, P. putida, M. hydrocarbonoclasticus , and P. geniculata for Copper (Cu), Iron (Fe), Cobalt (Co), and Zinc (Zn) nanoparticles (NPs) production sequentially as reported in our previous study Part I [ 38 ], were tested for advanced studies on soft rot ( Pectobacterium carotovorum subsp. carotovorum and Enterobacter cloacae ) and blackleg ( Dickeya solani ) genera, as follow:…”

“…Bacterial isolates from harsh conditions locals (industrial wastewater, seawater, wastewater, and lake water); were collected from Alexandria, Hurghada, and Damietta Governorates in Egypt. These bacteria were isolated in a previous study by the authors and published by Zaki et al [ 38 ]. Four selected isolates identified with accession No.…”

Biosynthesis of silver nanoparticles from curd whey for its anticancer activity

“…Energy-Dispersive X-ray spectroscopy (EDX):EDX analysis gives qualitative as well as quantitative status of elements that may be involved in the formation of NPs and proves the ability of bacterial cells to reduce and accumulate metalsfrom the culture medium [17] . In our study reveals that Energy dispersive Xray spectroscopic profile of AgNPs was confirmed by optical absorption peak at 3 keV, which is typical for silver nanocrystallite absorption.…”

Synthesis of organic–inorganic hybrid nanocomposites modified by catalase-like catalytic sites for the controlling of kiwifruit bacterial canker

“…First, low-cost commercial ZnO NPs serve as the active core of nanocomposite against Psa. [50][51][52][53][54] In addition, the incorporation of PDA ensures uniform deposition of the metal enzyme-like active sites on the surface, enhancing biocompatibility. 55 The nanocomposites, with excellent CAT-like activity, exhibit K m and V max values superior to that of most reported nanozymes, efficiently converting H 2 O 2 into O 2 .…”