You have no items in your shopping cart.
Abstract
Zinc oxide nanoparticles (ZnONPs), commonly used in agriculture, are environmentally harmful due to production methods. Biodegradable, eco-friendly, and cost-effective biologically synthesized ZnONPs offer a sustainable potential alternative. The aim of the present study was to compare the antimicrobial activity of biologically synthesized and commercial ZnONPs against test phytopathogens isolated from soil. Bacteria and fungi phytopathogens were isolated from soil samples. The bacterial isolates were identified by morphological and biochemical methods, while the fungi were identified using phenotypic characterization. The identities of the most probable bacterial and fungal isolates were confirmed by molecular characterization. DNAs were isolated from the isolates and used as templates for a polymerase chain reaction (PCR). Part of the 16S and ITS regions of the rRNA gene were amplified for the bacterial and fungal isolates, respectively. The PCR products were purified and sequenced. The nucleotide sequences were subjected to bioinformatics analysis. The phylogenetic relationship between each of the isolates was constructed using the Neighbor-Joining method program in the Geneious package. Zinc oxide nanoparticles were biologically synthesized using zinc nitrate hexahydrate and Moringa oleifera leaves. The commercial ZnONPs were prepared according to the manufacturer’s instructions. Both the biologically synthesized and commercial ZnONPs were characterized using spectrophotometric analysis. The antimicrobial activity of both the biologically synthesized and commercial ZnONPs was evaluated using the agar well diffusion and poison plate methods. The results showed that species of Pseudomonas and Pantoea were among the bacterial isolates, while species of Aspergillus and Penicillium were among the fungal isolates. The molecular characterization confirmed the identities of the isolates as Pseudomonas syringae and Pantoea agglomerans (bacteria) as well as Aspergillus niger and Penicillium chrysogenum (fungi). Similar absorbance values were obtained for the spectrophotometric analysis of both types of ZnONPs. However, the biologically synthesized ZnONPs showed higher antibacterial and antifungal activities against the test isolates compared to the commercial ZnONPs. The findings of the present study suggest that the biologically synthesized ZnONPs could be a suitable, efficient, and cost-effective alternative as an antimicrobial agent vis-à-vis the commercial counterpart.
