Bringing resistance modulation to epidemic methicillin resistant S. aureus of dairy through antibiotics coupled metallic oxide nanoparticles

The current study probed methicillin resistant S. aureus from milk of different dairy farms along with its response to multiple antibiotics, assessment of risk factors, and response to antibiotic coupled nanoparticle. XRD of Np was confirmed as miller indices (hkl) values i.e. (101), (100), (002), (110), (012) and (013) while STEM finally revealed 40-60 nm nanorods in aggregated form. Total of 6 preparations viz a viz gentamicin (G), chloramphenicol (C), zinc oxide nanoparticle (Np), gentamicin coupled Np (GNp), chloramphenicol coupled Np (CNp), and simultaneously coupling of gentamicin and chloramphenicol on Np (GCNp) were formulated for their potential to bring resistance modulation. Data analysis of this study revealed 24.59% MRSA from dairy milk appearing potentially associated (OR> 1, p < 0.05) with most of assumed risk factors. MRSA in response to various antibiotics showed highest resistance against amoxicillin (100%), penicillin (100%), vancomycin (100%), and linezolid (90%). Zone of inhibitions were increased by 249.76% (GNp), 184.86% (CNp), and 279.76% (GCNp) in case of coupled preparations. Significant reduced minimum inhibitory concentration was observed in case of GCNp (7.8125 ± 0.00 μg/mL) followed by GNp (15.00 ± 0.00 μg/mL) and CNp (41.67 ± 18.042 μg/mL) as compared to Np alone (125.00 ± 0.00 μg/mL). Minimum bactericidal concentrations for GCNp, GNp, and CNp, and Np were 31.125, 62.5, 125, and 500 μg/mL, respectively. The study thus concluded increased prevalence of MRSA while coupling of ZnO nanoparticles with antibiotics significantly brought resistance modulation to MRSA.