Uncovering the Phytochemical Basis and the Mechanism of Plant Extract-Mediated Eco-Friendly Synthesis of Silver Nanoparticles Using Ultra-Performance Liquid Chromatography Coupled with a Photodiode Array and High-Resolution Mass Spectrometry

Plant extract is a complex concoction of several phytochemicals, for instance, phenolics, sugars, flavonoids, xanthones, and others. In general, it said that hydroxyl-rich phenolics act as reducing agents metal ions, but little discussed about the stabilizing ligands nanoparticles (NPs). Thus, despite popularity plant extract-mediated synthesis NPs, phytochemical basis process exact mechanism are still unclear. Herein, systematic study was carried out to unveil St. John’s wort (Hypericum perforatum (H. perforatum) L.) silver (Ag) NPs. Among phytochemicals present in extract, phenolic acids flavonoids shown be involved reduction Ag+ while xanthones phloroglucinols capping agents, naphthodianthrones were both steps. Analysis postreaction residues by ultra-performance liquid chromatography coupled with photodiode array high-resolution mass spectrometry showed sharp decrease concentration various secondary metabolites which large amounts recovered from Consequently, low polar fraction H. rich phloroglucinols, pure compounds these classes (mangiferin hyperforin) did not reduce ions. contrast, naphthodianthrones, (kaempferol-3-glucoside, quercetin, quercetin-3-glucoside, hypericin, pseudohypericin, protohypericin) able Overall, contributes significantly understanding green NPs extracts.