Bioreduction and Stabilization of Nanosilver using Chrysanthemum Phytochemicals for Antibacterial and Wastewater Treatment

An easy, sustainable, and one-step method has been explored to synthesize colloidal silver nanoparticles (AgNPs) using Chrysanthemum (CT) flower extract and applied for antibacterial treatment and azo dye catalysis. The synthesis parameters (effect of CT extract concentration, reaction temperature, time, and pH) were thoroughly examined via a one-variable-at-a-time (OVAT) method to identify an optimization condition. The characterization of AgNPs produced at as-obtained optimum condition found that the nanoparticles are primarily spherical/oval shape, nanometer size (1.98 +/- 0.57 nm), very crystalline (d-spacing=0.236 nm), significantly stabilized (zeta potential=-22.1 mV). The characterizations also indicated that the AgNPs were produced by the redox reaction between plant phytochemicals and metal cations and stabilized via encapsulation of plant phytochemicals. The bacterial resistivity AgNPs was monitored by the agar disk diffusion test and found to be highly effective towards both Staphylococcus aureus (+ev) and Escherichia coli (-ev) bacteria. Moreover, the synthesized AgNPs displayed an innate catalytic reduction of azo dyes such as acid red 1 (AR1) and acid blue 29 (AB29). The degradation reactions were followed pseudo-first-order kinetics model and the rate constants k were calculated to be 0.45528 min(-1) (r(2)=0.94465) for AR1 and 0.28214 min(-1) (r(2)=0.88764) for AB29, respectively. This study reveals the prospect of CT flower extract as a botanical source for the biosynthesis of AgNPs and its potential application in bacterial reduction and azo-contaminated wastewater treatment.