Biogenic Fabrications of Silver Nanoparticles Using Plant Extracts and their Applications against Antibiotic Resistant Pathogens

Abstract

Nanoparticles are excellent findings of nanotechnology. Their unique properties and potential applications have increasingly attracted scientific community day by day to solve some health-related issues of the world. In pharmacy and medicine, silver nanoparticles (AgNPs) have vast potential due to their applicability and versatility. Biogenic synthesis of silver nanoparticles production using plants extracts is a favorable method for their diversity and availability as well as pharmacological activity. This method has numerous advantages such as being rapid, eco-friendly, and cost-effective. Therefore, this work aimed to optimize biogenic AgNPs synthesis procedure using leaves extracts of Olea europaea (Olive), Ficus carica (Fig), Ziziphus spina-Christi (ZSC), and Catha edulis (Qat) leaves. Phytochemical screening of aqueous leaf extracts was carried out. Procedure conditions including pH, incubation time, temperature, and amount of leaves extract were fully optimized during the experiments. Biogenic AgNPs were characterized using different analytical techniques. Anti-bacterial and anti-fungal activities of AgNPs were evaluated against Escherichia coli and Staphylococcus aureus (both sensitive & resistant strains) pathogenic bacteria as well as isolates Candida albicans resistant. Ultraviolet-visible spectra of biogenic AgNPs solution showed maximum wavelength (λmax) peak at 398, 419, 418, and 403 nm of Olea europaea, Ziziphus spina-Christi, Ficus carica, and Catha edulis respectively, agreeing to the silver nanoparticle plasmon absorbance. Fourier transform infrared spectra (FTIR) of AgNPs showed involvement of various bio-organic metabolites that played a critical role in formation silver nanoparticles, capping, and stabilization. Analytical techniques revealed that silver nanoparticles were spherically shaped and crystalline in nature with an average diameter between 25 and 32 nm (Olea europaea), 32 and 44 nm (Ficus carica), 32 and 41.9 nm (Ziziphus spina), 27 and 32 nm (Catha edulis) as estimated from X-Ray Diffraction and Scanning Electron Microscopy images. Significant anti-bacterial and anti-fungal activities of AgNPs were exhibited against human pathogenic Staphylococcus aureus and Escherichia coli (both sensitive & resistant) bacteria as well as isolates Candia albicans resistant. Interestingly, biogenic AgNPs revealed high anti-bacterial and anti-fungal activities that were superior to standard antibiotics, leaves extract, and AgNO3. This biogenic noble metal nanoparticle is highly promising and economically viable. Thus, it can be used as an alternative approach for treating antimicrobial resistance (AMR) pathogens after conducting further investigation.