The Role of MgO and CaO Nano-Particles on Staphylococcus Epidermidis Isolated from Catheter Indwelling Patients

The role of nano-particle metal oxides MgO and CaO as inhibitors to bacterial growth has been evaluated. The bacterial samples collected from catheters at a number of medical centers are diagnosed by culturing and biochemical tests to yield 18 isolates of S. epidermidis. Identification and particle size of the received MgO NPs, and CaO NPs are analyzed by X-ray diffraction. These are then examined for their antibacterial activity against S. epidermidis by the agar diffusion method, biofilm inhibition and minimum inhibitory/bactericidal concentration (MIC/MBC). The outcomes of the inhibition zone show that both MgO NPs and CaO NPs spread similar zone activity of (25 mm ± 2 mm) at 10 μg/ml concentration. For the biofilm inhibition, MgO NPs had (82%), and CaO NPs had (76%) at 10 μg/ml indicating good inhibition to biofilm formation. The test of MIC/MBC showed that MgO NPs are more efficient at lower concentration (1.25 μg/ml) in comparison with CaO NPs (2.5 μg/ml). Above these concentrations, complete inhibition of S. epidermidis is observed as an indication of the efficacy of these inorganic nano-particles in suppressing the growth of bacterial invasion.