Biosynthesis and Antibacterial Activity of Silver Nanoparticles Using Medicinal Plants Associated Endophytic Bacteria From in Riyadh Region Saudi Arabia

Abstract

Medicinal plants have been used by secondry communities to patronize various ailments. However, the capability of endophytes within these bio-prospective medicinal plants remains anonymous. The biosynthesis of silver nanoparticles (AgNPs) via the use of endophytic bacteria is a secure alternative for the chemical method. Plants were collected from Al Mamaria and several locations in the desert of Riyadh, Saudi Arabia. The microbial profile of the examined locations was analyzed using a 16S rRNA-based technique. Based on 16s rRNA and phylogenetic analysis, the selected isolates were identified. The bacterial extracts were tested for antibacterial activity and pharmacological characteristics. The 16S RNA-sequencing and phylogenetic analysis revealed that selected 24 isolates belongs to 4 phyla as following: Bacteroidota, Pseudomonadota formerly Proteobacteria , Actinomycetota, Bacillota (Firmicutes) have been isolated from different medicinal plants ((a)Cactus (b) Artemisia (c) Artemisia monosperma (d) Alhagi (e) Zizyphus(f) Teucrium (g) Ducrosia (h) Capparis spinosa ). Our 24 isolates selected from 121 isolates then purified by streaking on the same isolation medium based on dissimilarity in the color and shape of the colonies and then stored on slants at 4ºC and in 20% glycerol at -20ºC the rest of isolates stored for further analysis The dominated phyla was Actinomycetota , followed by Firmicutes . The Streptomyces genus was found in the majority of samples. The pharmacological characteristics of the bacterial extracts were assessed. Antibacterial testing revealed that 12 of 24 bacterial extracts were having antimicrobial activities against at least one of the microorganisms examined.