Metal nanoparticles from gold, silver, iron, copper, and others, range in size from 1 to 100 nanometers and have a broad variety of applications in computing, optics, cosmetics, food industry, medicine, and water treatment. Silver nanoparticles, known for their antimicrobial properties, are effective for remediating contaminated waters. Plant extracts are used as reducing agents for the environmentally friendly synthesis of silver nanoparticles. To improve this synthesis, identifying the biomolecules involved in the process is crucial. UHPLC-QTOF-MS and SIRIUS identified the key phenolic compounds involved in the silver reduction.