Green Synthesis of Silver Nanoparticles Using Olea europaea Leaf Extract for Their Enhanced Antibacterial, Antioxidant, Cytotoxic and Biocompatibility Applications.

Hanen Sellami,Abdurahman H Hirad,Shakeel Ahmad Khan,Ishaq Ahmad,Abdullah A Alarfaj,Ahmed E Al-Sabri

doi:10.3390/ijms222212562

Abstract

Herein, we report the green synthesis of silver nanoparticles (OE-Ag NPs) by ecofriendly green processes using biological molecules of Olea europaea leaf extract. Green synthesized OE-Ag NPs were successfully characterized using different spectroscopic techniques. Antibacterial activity of OE-Ag NPs was assessed against four different bacteriological strains using the dilution serial method. The cytotoxic potential was determined against MCF-7 carcinoma cells using MTT assay in terms of cell viability percentage. Antioxidant properties were evaluated in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. Biocompatibility was further examined by incubating the synthesized NPs with hMSC cells for 24 h. The results were demonstrated that synthesized OE-Ag NPs presented excellent log10 reduction in the growth of all the tested bacterial strains, which as statistically equivalent (p > 0.05) to the standard antibiotic drug. Moreover, they also demonstrated excellent cytotoxic efficacy against the MCF-7 carcinoma cells compared to plant lead extract and Com-Ag NPs. Green synthesized OE-Ag NPs appeared more biocompatible to hMSC and 293T cells compared to Com-Ag NPs. Excellent biological results of the OE-Ag NPs might be attributed to the synergetic effect of NPs’ properties and the adsorbed secondary metabolites of plant leaf extract. Hence, this study suggests that synthesized OE-Ag NPs can be a potential contender for their various biological and nutraceutical applications. Moreover, this study will open a new avenue to produce biocompatible nanoparticles with additional biological functionalities from the plants.

Highlights

The emergence of drug resistance in different bacteria has become a significant public health problem
Multi-drug resistant (MDR) bacteria were defined as bacteria that acquired resistance to at least one antibiotic from three or more classes of antibiotics and are frequently responsible for infection associated with healthcare settings [1]
Olea europaea is a rich source of different biological important secondary metabolites that can be used for the synthesis of biogenic nanoparticles as reducing and capping agents [23,24]

Summary

Introduction

The emergence of drug resistance in different bacteria has become a significant public health problem. Antibiotics have been used as an effective treatment against bacterial exposure owing to their satisfactory outcomes Their great use without maintaining prescription policies leads to increased antibiotic resistance in bacteria. Nanotechnology has provided many multi-disciplinary research concepts in the scientific area, which can overcome this challenging situation [4] This technology has led to the design and fabrication of nanomaterials and nanoparticles with exceptionally high surface area to volume ratio and small size, which determines their physical, chemical, mechanical, optical, electrical, solubility, and stability. In recent years, nanobiotechnology has been established as a new branch of nanotechnology This technology combines biological systems with physical and chemical procedures to produce nano-sized particles with specific functions [6]. In typical NPs biosynthesis, plant extracts were used as reducing and stabilizing agents

Methods

Results

Conclusion