**Master’s Thesis Defense of the Student (Lama Mohammed Hussein Hadi) in the Department of Physiology and Medical Physics at the College of Medicine, Al-Nahrain University**
The Department of Physiology and Medical Physics at the College of Medicine, Al-Nahrain University, discussed a master's thesis submitted by the student Lama Mohammed Hussein Hadi, entitled:
"Evaluation of Green Synthesized of Magnesium Oxide and Magnesium Oxide- Fullerene Composite Nanoparticles Antibacterial Activities against Pseudomonas aeruginosa and Staphylococcus aureus Multidrug Resistant Isolates."
The thesis aimed to:
Conduct green synthesis and detailed analysis of the structural (XRD), morphological (FESEM and TEM), and optical (UV-Vis) characteristics of magnesium oxide nanoparticles (MgO NPs).
Evaluate the antibacterial activity of the green synthesized MgO nanoparticles against Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa.
Assess the impact of adding C60 (fullerene) to MgO nanoparticles in terms of enhancing their antibacterial activity.
The study reached several important conclusions, most notably:
The formation of MgO nanoparticles as fine nano-sheets, a morphology not previously reported, which increased their effective surface area and enhanced their antibacterial activity.
The biological activity was tested against Pseudomonas aeruginosa (Gram-negative) and Staphylococcus aureus (Gram-positive), where both the nanoparticles and the composite demonstrated inhibitory effects on bacterial growth.
The minimum inhibition zone diameter for MgO was 10.2 mm, increasing to 21 mm at a concentration of 5 µg/mL.
The C60–MgO composite showed a significant synergistic effect, achieving a 14 mm inhibition zone at a low concentration (1.25 µg/mL), reaching up to 20 mm against both bacterial strains.
The half-maximal inhibitory concentration (IC50) values were determined: for Pseudomonas aeruginosa, 41.45 µg/mL for MgO and 20.27 µg/mL for C60–MgO, indicating enhanced activity with fullerene incorporation.
For Staphylococcus aureus, the IC50 of MgO was approximately 24.456 µg/mL, which decreased to 15.64 µg/mL with the composite, reflecting a potent synergistic antibacterial effect.
Finally, a molecular docking study was conducted to explore the mechanism of inhibition. Results showed that fullerene molecules interact with active binding sites in bacterial proteins, with binding energies of –2.41 kcal/mol against Staphylococcus aureus and –1.96 kcal/mol against Pseudomonas aeruginosa.
