Green Biosynthesized Silver Nanoparticles using Ficus deltoidea Leaf Aqueous Extract as an Antibacterial Agent
Ibrahirul Qamil Ismail (a), Nik Ahmad Nizam Nik Malek (a*,b), Hariz Asraf Hassan (a), and Shahrulnizahana Mohammad Din (a)

a) Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 UTM Johor, Malaysia
*niknizam[at]utm.my
b) Centre for Sustainable Nanomaterials (CSNano), Ibnu Sina Institute for Scientific and Industrial Research (ISI-ISIR), Universiti Teknologi Malaysia (UTM), 81310 UTM Johor, Malaysia

Abstract

This study aimed to synthesize silver nanoparticles (AgNPs) using a greener synthesis, utilizing Ficus deltoidea plant extract as a reducing and stabilizing agent that is capable for inhibiting bacterial growth. A preliminary study was conducted to analyze the antioxidant activity of the leaf plant extract by determining its total phenolic and flavonoid contents. Before synthesizing the AgNPs, the synthesis process was optimized with different parameters to ensure the highest possible yield of AgNPs including different leaf extract concentrations, pH, volume, synthesis temperature, and reaction time. The optimal synthesis conditions were used to synthesize AgNPs and were subjected for stability analysis and characterization. The formation of AgNPs was monitored by using UV-vis spectroscopy. Next, the biosynthesized AgNPs were characterized by using Fourier transform infrared spectroscopy (FTIR) and compared with colloidal AgNPs with plant extract (FdAgNPs) and the unmodified plant extract (FdEx). The extract obtained the most prominent protein peaks at 3400, 1600, and 1360 cm1, which acts as a reducing agent and helps reduce the silver ions to AgNPs. Further characterization of the biosynthesized AgNPs was conducted using X-ray diffraction (XRD) to determine their crystal latices and structure. Peaks obtained at 38, 46, 64, and 76 in AgNPs corresponding to (111), (231), (220), and (311) sets of lattice planes, which are closely connected with the for Ag. The disc diffusion technique (DDT) for antibacterial assay of the AgNPs showed significant formation of halo-zone for Gram-Negative (Escherichia coli) and Gram-Positive (Staphylococcus aureus). It can be concluded that the green synthesis of AgNPs using F. deltoidea plant extract exhibits antibacterial effects against wide spectrum of bacteria (Gram-Negative and Gram-Positive).

Keywords: Green Synthesis, Silver Nanoparticles, Ficus deltoidea, Antibacterial

Topic: Bionanotechnology