Antibacterial and antioxidant activity of gamma star-like MnO2 nanostructure with and without coating with iron oxide nanoparticles Gulboy Abdolmajeed Nasir, Zahraa Hasan Raheem, Huda Musleh Mahmood, Suhayla Khalid Mohammed Experimental and Theoretical Nanotechnology, 2026 Bacterial resistance caused by antibiotic misuse has garnered substantial attention, prompting numerous researchers to develop materials that can combat these resistant pathogens. The hydrothermal method is employed to produce γ-MnO2 nanostars and to coat them with Fe2O3 nanoparticles. The materials are characterized using XRD, FE-SEM, EDX, and UV-vis spectrophotometry, as well as antioxidant and antibacterial activities. The nano γ-MnO2 star shapes are coated with tiny spherical Fe2O3 nanoparticles with diameters of 35-47 nm. The peaks located at the crystal planes (120), (031), (131), (230), (300), (160), (421), and (003) are represented by the values of 2θ = 22.36º, 34.36º, 37.22º, 38.78º, 42.56º, 56.14º, 65.48º and 68.82º, respectively, and no additional peaks for any more materials showing pure γ-MnO2. The SEM descriptions of the star shapes of γ-MnO2 nanostructure in three different magnifications. The diameters of the six-branched star-shaped γ-MnO2 are about 140 nm close to the star's center, 55–70 nm close to its tips, and 1.5–4 μm in length. The EDX analysis of the γ-MnO2 nanostars are coated with Fe2O3 nanoparticles. It clearly shows the elemental composition that includes Mn, O, and Fe. The radical scavenging performance of the γ-MnO2 nanostars coated with Fe2O3 nanoparticles is showed substantial enhancement compared to bare γ-MnO2 nanostars. The prepared materials exhibit comparable antibacterial properties, with noticeable activity against Gram-negative strains (Salmonella and Escherichia coli), but no effectiveness against Gram-positive strains (Bacillus subtilis and Staphylococcus aureus).
Synthesis of different manganese dioxide nanostructures and studding the enhancement of their electrochemical behavior in zinc - Mno2 rechargeable batteries by doping with copper Z. H. Raheem, A. M. A. Al Sammarraie Aip Conference Proceedings, 2020 Different crystal forms of MnO2 nanostructures (α, β, γ, and δ) had been successfully synthesized using hydrothermal method with different reaction time, temperature, and reacting materials. Doping the MnO2 crystal structures with small amount of copper was accomplished. The prepared materials were characterized using XRD, FE-SEM, EDX to confirm the chemical composition and to measure the crystal size. The doped and undoped MnO2 nanostructures were also applied in zinc-ion rechargeable batteries to study the electrochemical behavior of these nanostructures, and the results showed that samples doped with copper had better electrochmicla behavior and showed higher specific capacity in these batteries, and the highest value (306.8 mAh/g) was for Cu doped γ-MnO2 and it is very close to the theoretical value of the MnO2 (308.3 mA/g).
Study the antioxidant activity of sage (Salvia officinalis) leaves extract Saba J. Ajeena, Suhayla K. Mohammed, Zahraa H. Raheem Indian Journal of Public Health Research and Development, 2019 This study was carried out to evaluate two type of sage (salvia officinalis) leaves extracts (Ethanolic and Water extracts) by using two methods (reducing power and chelating ability). So this study shows the high content of phenolic compound of ethanolic and water extract of sage (15.8 and 14.6) % respectively. The leaves of sag were locally obtained, twenty gram of ground material was extracted by 250 ml ethanol 95% or distilled water at boiling point, under reflux for one hr. The extractive was filtered and evaporated at 50 C° to the compete dryness. Total phenol assay, total flavonoid assay, reducing power assay, and chelating ability assay were observed in this study. Results revealed that the ethanoic extract had highest percentage of reducing power than water extract of sage leaves as so as the chelating ability percentage.
Evaluation of some heavy metal contamination in Malva parviflora L. plant and soil obtained from gardens of college of Agriculture-University of Baghdad Zahraa Hasan Raheem, Afrah Abd Alhussain Jebor, Suhayla Khalied Mohammed Pakistan Journal of Nutrition, 2014 Heavy metals are given significant interest throughout the globe due to their toxic, mutagenic effects even at very low concentrations. Several cases of human diseases, disorders, malfunction and malformation of organs due to metal toxicity have been reported. Reports indicate that lead, cadmium and chromium may cause a wide variety of changes in biological systems, even at very low concentrations. Samples of different parts of Malva parviflora L. (leaves, stems and roots) and associated soils collected with increasing distance of 5, 25, 50, 100m from the gardens surrounding the chemistry labs in college of agriculture university of Baghdad in Abu Ghraib region in Baghdad. The parts of Malva parviflora L. (leaves, stems and roots) and the soil samples at depth 0-20cm were analyzed by atomic absorption spectroscopy after chemical treatment using acid digestion procedures, the pH and the electric conductivity of the soil were also measured. The concentrations Pd, Cr and Cd in the soil and plant of Malva parviflora L. were compared with the maximum allowable limits in different countries and they were beyond the maximum allowable limits in the plant samples but in the soil samples they were below the maximum allowable limits in the case of cadmium and below but very close to the maximum allowable limits of lead and chromium.
