<p>Conventional chemical synthesis strategies for nanomaterials often require significant energy and chemical inputs that compromise sustainability and can lead to undesired detrimental effects on environment. This has led to greater interest in novel synthesis platforms that have reduced chemical inputs and increased biocompatibility. We utilized extracts from two common agricultural wastes, soybean pods (SP) and tea residues (TR), to biosynthesize silver nanoparticles (Ag NPs) in one step process with AgNO₃. By comparing metabolite profiles before and after Ag NPs production, we identified 35 (SP) and 16 (TR) metabolites that were significantly depleted from the extracts, including reducing sugars, organic acids, and alcohols. The antioxidant potential of SP-Ag NPs and TR-Ag NPs were comparable to chemically synthesized Ag NPs (Com-Ag NPs) at 125 mg L^-1, and approximately equivalent to that of Com-Ag NPs above 500 mg L^-1. At doses above 500 mg L^-1, SP-Ag NPs had the highest inhibitory impact on Gram-negative <i>Escherichia coli</i> (ATCC 25922) growth, greater by 8.61–17.4% and 6.51–12.2% than TR-Ag NPs and Com-Ag NPs, respectively. These results suggested that SP and TR metabolites can be used as reducing or capping agents to biosynthesize Ag NPs that possess strong antioxidant and antibacterial properties.</p>