The Influence of Moringa oleifera Biomass and Extraction Methods on Biogenic Synthesis of Iron Nanoparticles for Inhibition of Microbial Pollutants

Biogenic nanoparticles have recently emerged as promising bacterial growth inhibitors, requiring low concentrations and not producing harmful byproducts. However, knowledge gaps remain regarding how different extraction techniques affect nanoparticle synthesis, thereby influencing their replicability and scalability across various applications. To address these knowledge gaps, this study compared six extracts derived from Moringa oleifera biomass for the synthesis of iron oxide nanoparticles. Multivariate statistical analyses correlated extraction methods with biomolecule content (polyphenols, flavonoids, carbohydrates, proteins), iron percentage, and E. coli growth inhibition. All extracts showed varying concentrations of biomolecules, and different extraction methods were preferable for specific components. Flavonoids were best extracted by salting-out, while infusion methods were better for obtaining carbohydrates. Higher percentages of iron (22.77%) were linked to the presence of polyphenols and flavonoids. Nanoparticles prepared using salting-out and infusion extraction from leaf biomass displayed the highest efficiency in inhibiting E. coli growth, up to a dilution factor of 4. The outcomes of this research study provide an in-depth understanding of the role of specific biomolecules in biogenic nanoparticle synthesis, confirming that both synthesis yield and application effectiveness depend on the extract preparation method.