Sonication-assisted green synthesis of silver nanoparticles using Piper retrofractum fruit extract and their antimicrobial assay

In this study, silver nanoparticles (AgNPs) were synthesized using aqueous extract of Piper retrofractum fruits by the sonication-assisted an eco-friendly method. The compounds of Piper retrofractum extract can perform as reducing as well as capping agent in the synthesis process of AgNPs. Silver nitrate was used as a starting material and was reacted with Piper retrofractum extracts. The formation of AgNPs was monitored by a color change from colorless to dark brown. The synthesized AgNPs were characterized using UV-Visible, FTIR, XRD, and FESEM-EDS analysis. Surface plasmon resonance peak of silver nanoparticles analyzed using a UV-Vis spectrophotometer was observed at 476 nm. FTIR spectrum of silver nanoparticles peaks at 3420 cm-1, 2922 cm-1, 1632 cm-1, and 1021 cm-1 was similar to the Piper retrofractum extract spectrum, which indicated the compounds might involve in stabilizing nanoparticles, whereas the additional new peaks at 702 cm-1 and 535 cm-1 revealed the characteristic band of Ag-O-H. The X-ray diffractogram showed the crystalline properties of silver nanoparticles, and the average crystallite size was found around 24.86 nm. The spherical shape of morphology silver nanoparticles was observed in the SEM photograph. EDS spectrum showed the high presence of silver. Synthesized silver nanoparticles exhibited antimicrobial activity against E.coli and S.aureus. This study reported the successful green synthesis of AgNPs implementing of plant extract.