Antibacterial activity of silver nanoparticles synthesized from Citrus aurantium and its synergistic effect of the combination of silver nanoparticles with ampicillin against Proteus mirabilis

Abstract

Abstract Background: Proteus mirabilis is one of the most infectious organisms that cause a various infections involving those of the skin, wounds, and urinary tract. This study describes the synthesis of silver nanoparticles (AgNps) and using it as an antibacterial agent. Objective: To determine the activity of AgNps and synergistic effect of combination of AgNps with ampicillin (AMP). Materials and Methods: Out of 205 samples, 32 isolated were identified as P. mirabilis and determine the inhibition zone by using AgNps and its combination with AMP. The AgNps were biosynthesized by Citrus aurantium and then characterized using Ultraviolet (UV)-visible spectroscopy, X-ray diffraction (XRD) and transmission electron microscope (TEM). The antibacterial activity of AgNps was done using well diffusion agar method and the activity was evaluated by calculating the increase in the inhibition zone and reduction in the bacterial growth. Results: The synthesized AgNps was first characterized by UV-visible spectroscopy which showed a peak between 400 and 500 cm–1. The color changes from clear yellow to red or brown color indicate the formation of AgNps. The particle size of AgNps was calculated and found to be 21.24 nm by XRD. The TEM images showed the presence of very regular particles in shape of nanospheres with a particle size in the range of 10–28 nm. Different concentrations (25, 50, 75, 100 µg/mL) were used for determining the activities of AgNps and the combination of AgNps with AMP, and the result showed that the most efficient in inhibition zone was at concentration 100 µg/mL. Conclusion: This study concluded that the green synthesized AgNps from C. aurantium leaves extract have most potential as antibacterial against P. mirabilis.