Evaluation of the Antimicrobial Activity of ZnO Nanoparticles against Enterotoxigenic Staphylococcus aureus

Reham M El-Masry; Dalia Talat; Shahira A Hassoubah; Nidal M Zabermawi; Nesreen Z Eleiwa; Rasha M Sherif; Mohammed A S Abourehab; Randa M Abdel-Sattar; Mohammed Gamal; Madiha S Ibrahim; Ahmed Elbestawy

doi:10.3390/life12101662

Evaluation of the Antimicrobial Activity of ZnO Nanoparticles against Enterotoxigenic Staphylococcus aureus

Life (Basel). 2022 Oct 20;12(10):1662. doi: 10.3390/life12101662.

Authors

Affiliations

¹ Directorate of Veterinary Medicine, El-Gharbia 31515, Egypt.
² Department of Microbiology, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt.
³ Department of Biological Sciences, Microbiology, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
⁴ Animal Health Research Institute, Agriculture Research Center (ARC), Giza 12618, Egypt.
⁵ Laboratory of Directorate of Veterinary Medicine, Kafr El-Sheikh 33516, Egypt.
⁶ Department of Pharmaceutics, College of Pharmacy, Umm Al-Qura University, Makkah 21955, Saudi Arabia.
⁷ Department of Pharmaceutics and Industrial Pharmacy, College of Pharmacy, Minia University, Minia 61519, Egypt.
⁸ Biomedical Sciences Department, College of Pharmacy, Shaqra University, Shaqra 11961, Saudi Arabia.
⁹ Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Beni-Suef University, Alshaheed Shehata Ahmad Hegazy St., Beni-Suef 62514, Egypt.
¹⁰ Department of Poultry and Fish Diseases, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt.

Abstract

Staphylococcus aureus (S. aureus) is a Gram-positive bacteria considered one of the leading causes of community and hospital-acquired illnesses or public health concerns. Antibiotic resistance in this microorganism is one of the greatest issues in global health care. The use of metal nanoparticles and their oxides is one of the potential approaches to combating bacteria resistance to antibiotics. The antibacterial properties of ZnO NPs against enterotoxigenic S. aureus were studied. ZnO NPs were tested in vitro by agar diffusion test. They resulted in 26 and 22 mm zones of inhibition for a size of 20 nm and a concentration of 20 mM against 10⁵ and 10⁷ CFU/mL S. aureus, respectively. The MIC of ZnO NPs of various sizes, 20 and 50 nm, with 10⁵ CFU/mL was 2.5 and 5 mM, respectively. MIC with 10⁷ CFU/mL was five mM for 20 and 50 nm ZnO NPs. Further, the highest growth reduction percentage, 98.99% in the counts of S. aureus was achieved by ZnO NPs of size 20 nm and concentration of 10 mM. Moreover, the obtained ELISA results indicated a significantly decreased concentration of enterotoxin A with all concentrations and sizes of ZnO NPs. PCR analysis showed a significant effect on sea gene in response to ZnO NPs treatments leading to loss of the gene, unlike the unaffected nuc gene. Moreover, morphological changes and cell shape distortion were detected by scanning electron microscope for bacterial cells treated with ZnO NPs.

Keywords: Gram-positive bacteria; MIC; enterotoxin A; nanoparticles.

Grants and funding

The authors would like to thank the Deanship of scientific research at Umm Al-Qura University for supporting this work by grant code (22UQU4290565DSR94).