Biological synthesis of iron oxide nanoparticles and evaluation of its antibacterial and antioxidant property

Iron oxide nanoparticles (IONPs) have become a great interest among the researcher as it has a broad range of advantageous application in the pharmaceutical industries as well as healthcare settings. The present study was focused on the synthesis of IONPs from the aqueous extract of Piper betle leaves belongs to the genus Piper of the family Piperaceae and to evaluate the antibacterial activity against various pathogens. IONPs were synthesized from Piper betle leaf extract using 3mM of iron (III) chloride (FeCl3). The characterization of IONPs was done through UV-Vis spectroscopy, TEM, FTIR, and Zeta potential analysis.  Then, the synthesized IONPs were tested for antibacterial activity against five different pathogens, which are Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhi, Escherichia coli, and Vibrio Cholera. The synergistic effect of IONPs were evaluated with ceftriaxone, gentamicin and amoxicillin. Furthermore antioxidant activity was determined using DPPH assay. The maximum absorption peak of IONPs was found at 320 nm through UV-Vis spectroscopy. The synthesized IONPs were spherical in shape with size ranges from 10 - 15 nm through TEM analysis. From FTIR spectroscopy, significant peaks were observed and showed the presence of a hydroxyl group, amine, alkane, amide, and nitrile groups, respectively. Zeta potential analysis showed IONPs were stable. The synthesized IONPs showed significant antibacterial activity against all the selected pathogens. The maximum zone of inhibition was observed on Vibrio cholera increased as the concentration of the IONPS increased. The IONPs exhibited a good synergistic effect with ceftriaxone as compared to gentamicin and amoxicillin. The IONPs showed good antioxidant properties through DPPH assay at 40 µg/ml. The IONPs were successfully synthesized from Piper betle leaf extract, which demonstrated significant antibacterial activity against various bacterial pathogens and also exhibited good antioxidant activity.