Contamination by heavy metals is one of the major environmental problems in many countries and these contaminants reach from various sources such as traffic cars and other activities. Soil and phylloplane samples were collected from eight traffic and two non-traffic sites in Sohag city, Egypt. Heavy metal contents of Cd²⁺, Zn²⁺ and Pb²⁺ of soil and phylloplane samples were determined and revealed high levels of Zn²⁺ and Pb²⁺ in traffic samples. A total of 112 bacterial and 62 fungal isolates were obtained from soil and phylloplane. Bacterial isolates were characterized on the basis of morphological, physicochemical and biochemical characteristics; and 16S rRNA gene sequences. Fungal isolates were identified according to morphological characterization. Minimal inhibitory concentrations (MICs) of Cd²⁺, Zn²⁺ and Pb²⁺ for each isolate were detected. All bacterial and fungal isolates demonstrated resistance to lead with MICs >0.528 mM and >0.211, respectively. Moreover, the maximum MICs of cadmium and zinc for bacteria were 0.821 mM and 1.471 mM, respectively, where as, MICs for fungi were 0.328 mM and 0.588 mM, respectively. The most resistant bacterial and fungal isolates were Pseudomonas aeruginosa RA65 and Penicillium corylophyllum, respectively. Therefore, P. aeruginosa RA65 was selected for further investigations. Growth curve study showed that 0.264 mM lead had no efficiently effect on the growth of P. aeruginosa RA65. Plasmid isolation evidenced by transformation studies indicated that P. aeruginosa RA65 harbored a single plasmid (~9.5 kb) which mediated heavy meal resistance. Consequently, these microbial isolates could be potentially used in bioremediation of heavy metal-contaminated environment.
Heavy metals are considered as dangerous pollutants even in relatively low concentrations. Biosorption is an ecofriendly technology that uses microbial biomasses for adsorbing heavy metals from wastewater on their surfaces based on physicochemical pathways. Ten agricultural wastewater samples were collected from different sites in Sohag Governorate, Egypt. One hundred and nineteen zinc and cadmium-resistant bacterial isolates were recovered from the water samples. Interestingly, the isolate R1 was selected as the most resistant to Zn2+ and Cd2+. This isolate was morphologically and biochemically characterized and identified by sequencing of 16S rRNA gene as Priestia megaterium, and then deposited in the GenBank database under the accession number PRJNA526404. Studying the effects of pH and contact time on the biosorption process revealed that the maximum biosorption was achieved within 50 min at pH 7 and 8 for Zn2+ and Cd2+, respectively, by the living and lyophelized biomass of Priestia megaterium PRJNA526404. The preliminary characterization of the main chemical groups present on the cell wall, which are responsible for heavy metal biosorption, was performed by Infrared analysis (IR). Kinetics studies revealed that data were fitted towards the models hypothesized by Langmuir and Freundlich isotherm equations. The maximum capacity values (qmax) for biosorption of zinc and cadmium reached by using living and lyophelized biomass were 196.08; 227.27 and 178.57; 212.777 mg/g, respectively, and it was indicated that lyophilization improved efficiency of the biomass to heavy metals compared to living cells. The results indicated that Priestia megaterium PRJNA526404 had good application prospect in cadmium and zinc water remediation.
Copper oxide nanoparticles (CuONPs) were synthesized by a green method using aqueous extract of Cystoseira myrica as capping and reducing agent. A UV-visible spectrophotometer was used to characterize the produced nanoparticles. The aqueous extract of C. myrica at pH 5 and 100°C after 150 minutes was shown to be the optimal condition for the synthesis of copper oxide nanoparticles. The Structure and characters of synthesized nanoparticles were confirmed using TEM, DLS, XRD, and FTIR. The efficiency of different concentrations of copper oxide nanoparticles (25, 50, 75, 100) µg/ml synthesized from aqueous extract of C. myrica exhibit high antitumor activity against some cancer lines such as HepG2 and MCF-7. The percent of cell viability decreases as the concentration of nanoparticles rises. Copper oxide nanoparticles at a concentration of 100 µg/ml were found to have the lowest percentage of cell viability in HepG2 (18.7%), while MCF-7 was (19.27%).
El-Amir Muhammad's minaret in Akhmim, Sohag, Egypt, is constructed of limestone and has been exposed to many factors of damage as a result of the high levels of ground water. Limestone is strongly affected by ground water, especially when being impure. The current work discusses the results of analytical techniques including chemical testing to determine the types of soluble salts through optical microscopy, electronic scanning electron microscope with an X-ray energy dispersion system (ESEM) to study and determine the causes of rapid degradation. Microbial weathering phenomena toward limestone were also studied. Different bacteria and fungi were isolated from outdoors and indoors of air and limestone of the building of which Bacillus cereus OK447647, B. subtilis OK447648, Serratia marcescens OK447650, Pseudomonasoryzihabitans OK447649, Aspergillus flavus, A. niger, Penicillium chrysogenum and Cladosporium cladosporoids were the most representative. B. cereus OK447647 and B. subtilis OK447648 have shown ability for calcium carbonate dissolving. The minimal inhibitory concentrations (MICs) of sodium azide were investigated against the growth of microbial isolates. Sodium azide at 100 ppm was found to be the best treatment for bacterial isolates although it had no significant effect against fungi.
Ninety species in addition to three species varieties belonging to thirty-one genera were isolated and identified from three economic plant roots (Saccharum officinarum, Corchorus olitorius and Triticum aestivum) on PDA and water agar at 28±2˚C. Fusarium (15 species, 45/60 samples and 31.4% of total fungi) and Aspergillus (15+2, 34/60 and 17%) were the dominant genera on PDA, whereas, Fusarium (13 species, 38/60 samples and 33.8% of total fungi) and Drechslera (6, 28 and 13.1%) were the commonest on water agar media. Of the previous genera F. udum, F. anthophilum, F. subglutinans, A. terreus var. aureus, A. flavus, D. biseptata and D. bicolor were the most detected species on PDA and WA. The endophytic fungi isolated belonging to anamorphic fungi (57 species, 23 genera of 11 order), Ascomycotina (26, 4 of 1) and Zygomycota (1, 1 of 1) on PDA and (38, 15 of 8) & (11, 2 of 1) belonging to anamorphic fungi and Ascomycotina on WA, while Zygomycota disappeared on WA.
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