تأثير جسيمات الفضة النانوية المحضرة حيوياً بمستخلص أوراق السدر Zizphus lotus على بعض الأنواع البكتيرية الممرضة

تأثير جسيمات الفضة النانوية المحضرة حيوياً بمستخلص أوراق السدر

Abstract

This research aims to biosynthesize silver nanoparticles (AgNPs) using the aqueous extract of Ziziphus lotus leaves as a rapid, environmentally friendly and cost-effective method based on green chemistry approach. The aqueous extract of Ziziphus lotus leaves was able to reduce and stabilize silver ions by changing the color of the solution to reddish brown a few minutes after adding the aqueous extract. The produced nanoparticles were characterized using various techniques. UV-Vis spectroscopy revealed a distinct absorption peak at a wavelength of 430 nm, and scanning electron microscopy (SEM) showed spherical nanoparticles with sizes ranging from 40-120 nm in diameter. X-ray diffraction (XRD) confirmed the pure crystalline nature of the nanoparticles with a face-centered cubic structure and an average crystal size of about 21 nm. In addition, the active compounds responsible for the reduction of silver ions were examined using FT-IR spectroscopy. The biological activity of silver nanoparticles for the species was evaluated. Gram-negative and Gram-positive bacteria Pseudomonas aeruginosa Staphylococcus aureus, by determining the minimum inhibitory concentration (MIC) and minimum lethal concentration (MBC) at concentrations ranging from 1000 to 62.5 µg/ml. The minimum inhibitory concentration of silver nanoparticles for Gram-negative and Gram-positive bacteria was 250 and 500 µg/ml, respectively. The disk diffusion method was used to study the antibacterial activity of silver nanoparticles and it was found that they have effective activity against pathogenic and antibiotic-resistant bacteria and have greater effectiveness against Gram-negative bacteria than Gram-positive bacteria. P. aeruginosa bacteria recorded the highest inhibition zone with an average diameter of 12 mm, and S. aureus bacteria recorded an average diameter of 8.67 mm at a concentration of 1000 µg/ml. It was noted that with increasing concentration, the rate of inhibition diameter increased and a significant difference in the effect was found based on Concentrations (P-value ≤ 0.05).