Phytochemical Assisted Synthesis of AgNPs Using Artemisia lerchiana: Potential Antimicrobial Applications in Plant Disease Control

Silver nanoparticles are important because they have biological activity and physicochemical properties that make them useful. Silver, which is thought to be inert in nature, reacts with moisture in the skin and wound fluid to release ions, making it one of the most effective antimicrobial/antibacterial agents throughout history. However, this work illustrates the environmentally friendly production of silver nanoparticles (AgNPs) by employing leaf extract from Artemisia lerchiana as a stabilising and reducing agent. With a zeta potential of −20 mV and an average size of 165 nm, the biosynthesised AgNPs demonstrated stable colloidal characteristics. Gram-positive (Staphylococcus aureus, Bacillus subtilis), Gram-negative (Escherichia coli, Pseudomonas aeruginosa), and fungal (Candida albicans) strains were tested for antimicrobial efficacy. The results showed significant inhibitory effects, especially against Bacillus subtilis (MIC: 0.560 mg/mL) and C. albicans (MIC: 0.014 mg/mL). Additionally, using regression analysis, the ideal synthesis parameters were found to be 56°C, 6-unit extract, 2.4 mM AgNO₃, and an 8-min reaction time. These parameters produced AgNPs with improved antimicrobial activity (predicted MIC: 0.01 mg/mL). The results show that AgNPs mediated by Artemisia lerchiana have the potential to be an environmentally friendly antimicrobial agent, and they recommend more research into their mechanisms and potential uses in medicine.