• Biosynthesis of magnetic iron nanoparticles by Lactobacillus casei and investigation of antibacterial potential of them
  • Fatemeh Shahbazi,1,* Behin Omidi,2
    1. Department of Biology, Faculty of Basic Science, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
    2. Department of Biology, Faculty of Basic Science, Central Tehran Branch, Islamic Azad University, Tehran, Iran.


  • Introduction: Magnetic iron nanoparticles were used as drug carriers in the drug delivery system, and due to increased drug absorption and controllable and targeted drug release, they have been widely used in MRI imaging techniques, and the manufacture of anti-cancer and anti-tumor drugs have been used. Due to the wide applications of magnetic iron nanoparticles, several solutions have been presented for their synthesis, the most important of which are chemical methods. Still, in recent years, researchers have invented a new technique in which living organisms such as plants, bacteria, fungi, and algae are used as a bioreactor for the synthesis of nanoparticles, called biosynthesis or green synthesis. This research used the green synthesis method to produce magnetic nanoparticles, and the ability of Lactobacillus casei in The green synthesis of iron magnetite nanoparticles has been investigated.
  • Methods: prepared 1mM of Fe2so4 solution, and the supernatant of each of the Lactobacillus casei was added. The biosynthesis of MINPs was proved by UV-vis, XRD, FTIR, and TEM. The antimicrobial effect of MINPs was performed by disk diffusion method and MIC and MBC on Bacillus cereus, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.
  • Results: change of the indicates the biosynthesis of MINPs. Peaks in 441-450nm were observed in the UV-vis spectrophotometer. XRD and FTIR results also confirmed the biosynthesis of MINPs. The size of MINPs was between 20-30nm, and the shape was spherical. The results of the antimicrobial effect of MINPs by disk diffusion and MIC methods were Bacillus cereus 26± 0.5 and 30± 1.2, Staphylococcus aureus 21± 1 and 40± 0.8, Escherichia coli18 ± 0.5 and 65± 1, and Pseudomonas aeruginosa 14 ± 2 and 80 ±0.0
  • Conclusion: The results showed that all three species of Lactobacillus could biosynthesize MINPs, which has a suitable antimicrobial effect against gram-positive and gram-negative bacteria .
  • Keywords: Biosynthesis, Magnetic Iron Nanoparticles, Lactobacillus casei