Studying the effect of green synthesized iron nanoparticles on multi drug resistant bacteria isolated from wound

The aim of the current research was to explore the inhibitory activity of green synthesized iron nanoparticles against multidrug-resistant bacterial isolates. In the study, a total of 118 samples of different types of wounds (such as accidents, sharps wounds, surgical wounds, diabetic foot wounds and burns) were collected from patients admitted to the emergency and surgical wards of Tikrit General Hospital, Tikrit Teaching Hospital and Al-Tawfiq Al-Ahli Hospital between 1 September and December 2022. The swabs were taken from the depth of the wound and then transported to the laboratory at Tikrit University. Bacterial isolates were identified using cultural characteristics and biochemical tests, and the diagnosis was confirmed using the Vitek2 technique. Antibiotic susceptibility tests were conducted using a variety of antibiotics belonging to different groups, and the multi-drug-resistant isolates were determined. Iron nanoparticles were prepared biologically by using 5 ml of hibiscus extract as a reducing agent with a ferrous nitrate solution of 1 mM Fe(NO3)3.9H2O. The prepared nanoparticles were subjected to several tests, including UV-spectroscopy at 400 nm. The shape and dimensions were determined by scanning electron microscopy. Another test on Multidrug resistance isolates was performed to examine the production of virulence factors (hemolysin, biofilm, lecithinase, and protease) before and after exposure to the particles. The results showed that the predominant species isolates were Staphylococcus aureus, recording 23%, and Pseudomonas aeruginosa, 21%, followed by Proteus vulgaris, Enterobacter cloacae complex, Klebsiella pneumoniae, Staphylococcus epidermidis, Serratia marcescens, Sphingomonas paucimobilis, Acinetobacter lwoffli, Granulicatella adiacens, Yersinia enterocolitica, and Staphylococcus lentus, respectively. Concerning the antibiotic susceptibility pattern, our results revealed that twenty-five isolates were multidrug resistance; however, Meropenim and Emipenem were the most effective among antibiotics. The inhibitory results of iron nanoparticles gave an optimum inhibition zone of 33mm. Results of virulence factor production showed that hemolysin recorded 100%, the lecithinase factor was 83, and the percentage of protease in Staphylococcus aureus was 91%. As for the rest of the isolates, they produced all the virulence factors in varying proportions. As for the effect of iron nanoparticles after incubation with the bacteria, most isolates showed their ability to produce hemolysin when exposed to iron nanoparticles. As for the virulence factor protease, most bacterial isolates have lost their ability to produce it. When bacterial isolates were exposed to iron nanoparticles, the level of growth decreased and the level of inhibition increased. The results also showed that when isolates are exposed to iron nanoparticles, they are unable to produce biofilm and the virulence factor lecithinase. These results show that iron nanoparticles have the ability to inhibit bacterial growth. Our study reached the conclusion that the method for nanoparticle preparation was fast, low-cost, non-toxic, and effective against bacteria, including multi-drug-resistant bacteria. This may expand the horizons to the time era after antibiotics.