Antibacterial and Anti virulence Factors activity of ZnO nanoparticles Biosynthesized by Lactococcus lactis ssp. Lactis

Abstract

In the present we are used a probiotic bacteria Lactococcus lactis ssp. lactis which is isolated from fsh intestine to produce ZnO nanoparticles. Then we conformation the synthesized of nanoparticles using different techniques such as atomic force Microscopy (AFM) X-ray diffraction (XRD): technique, Fourier Transform Infrared’ Spectroscopy (FTIR), Scanning Electron Microscopic (SEM) and Energy-dispersive X.-ray analysis (EDX) spectra. The results of characterization showed that the nanoparticles are hexagonal ZnO crystal structure, spherically shaped with a diameter of about (31–36)nm. The biosynthesized ZnO nanoparticles were tested against pathogenic bacteria isolated from skin infections included Pseudomonas aeruginosa, Acinetobacter baumanii, Klebsiella pneumonia, and Staphylococcus aureus. The activity of ZnO nanoparticles as antimicrobial agent was measured via the investigation of the minimum inhibition concentration (MIC). The ZnO nanoparticles had antibacterial activity, the MIC ranged between (25–100) mg/ml. The anti-virulence factors also determined against tested bacteria. Results showed that the ZnO nanoparticles had ability to inhibit virulence factors the ability of β-hemolysin, urease and pyocyanin production were decreased after treatment with biosynthesized ZnO nanoparticles, also the best effect has been shown in bioflm formation after 72 h forall isolates, with high inhibition 62.18% against K.pneumoniae (K6).