Occurrence and Molecular Characterization of Methicillin-resistant Staphylococcus aureus in Marketable Milk and Soft Cheese: Effect of Curcumin and Ginger Nanoparticles on its Survival

This study was designed to record the occurrence of Staphylococcus aureus with special reference to the methicillin resistance isolate as well as some virulence factors in milk and soft cheese and the antibacterial effect of curcumin and ginger nanoparticles. The samples were collected over a period of December 2021 to April 2022 from different locations in Assiut Government, Egypt. The samples were subjected to microbiology and molecular analysis. From 100 samples of marketable milk and soft cheese (50 for each one), the results showed that 78 samples (78%) positive for Staphylococcus aureus, moreover the percentages of mecA gene were (21.06%). Also, the isolated strains were carried enterotoxins gene (sea) and alpha hemolysis gene (hlɑ) with percentages of 3.51 and 2.43%, respectively. Moreover, the curcumin and ginger nanoparticles (NPs) were prepared by the ultra-sonication method and were characterized by XRD, FTIR, and TEM. With the assistance of the well diffusion method, curcumin and ginger NPs showed antibacterial activity against methicillin-resistant Staphylococcus aureus. The minimum inhibitory concentration (MIC) was obtained by the micro broth dilution method which indicated that the lowest concentrations inhibit the growth of Staphylococcus aureus using curcumin and ginger NPs were 25 mg/ml and 50 mg/ml, respectively. In addition, the results revealed that the curcumin NPs have antibacterial activity higher than that of ginger NPs against MRSA.