Free Radical Scavenging and Antioxidant Activity of Silver Nanoparticles Synthesized from Cuminum cyminum (Cumin) seed Extract

Abstract

Silver nanoparticles are extensive, applied in different fields. Green methods using plants have been used as renewable resources for the synthesis of biodegraded nanomaterials, thereby providing economic and safe synthesis routes. The green synthesis was done using the aqueous Cumin seed extract and as a bio-reducer agent and aqueous AgNO3 solution as a precursor under various conditions. The formation of silver nanoparticles was confirmed by the observation of the shift in color from colorless to dark brown. The synthesized AgNPs were characterized using UV/V is spectroscopy, XRD, FTIR, and SEM. Also, the synthesized AgNPs were evaluated for their antioxidant activity (In-vitro) by DPPH assay. The bio-reduced mixture showed a maximum peak at around 388nm. The XRD peaks were observed at 38o and 46o, corresponding to 111, 200, 220, and 311, and the peak widening suggested a smaller particle size. The FTIR absorption spectra indicated the presence of residual plant extract as a reducing agent in the reaction mixture. Also, analysis of C. cyminum seed extract strongly suggested the presence of OH stretching in alcoholic and phenolic compounds as the main phytochemicals parts, which is supported by a strong peak at approximately 3296cm−1. The SEM images clearly showed that AgNPs were almost spherical in shape and 48.7nm in size. The synthesized AgNPs showed almost the same pattern of ascorbic acid-free radical scavenging activity except at concentrations 100 and 50µg/ml with significant differences (P≤0.05) and it is dose-dependent. Silver nanoparticles can be synthesized on a large scale following a simple and eco-friendly method using C. cyminum seed extract that can be used as an effective antioxidant.