Green synthesis of silver nanoparticles using aqueous extract of saffron ( Crocus sativus L.) wastages and its antibacterial activity against six bacteria

Objective: To synthesis silver nanoparticles (AgNPs) by using extract of saffron (Crocus sativus L.) wastages and to test their antibacterial activity against six bacteria. Methods: In this paper, the synthesis of AgNPs using aqueous extract of saffron wastage as a green method without any chemical stabilizer and reducer is demonstrated. The synthesized AgNPs were determined by UV-vis spectrum, high resolution transmission electron microscopy, X-ray diffraction, and Fourier transmission infrared spectroscopy analysis. Results: UV-vis spectrum showed a peak at 450 nm due to excitation of surface plasmon vibrations. Fourier transmission infrared spectroscopy showed that nanoparticles were capped with plant secondary metabolites. X-ray diffraction analysis also demonstrated that the size range of the synthesized nanoparticles was 12-20 nm. Transmission electron microscope image illustrated AgNPs with spherical shape and an average size of 15 nm. The result of antibacterial activities showed that the biosynthesized AgNPs had an inhibiting activity against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Shigella flexneri and Bacillus subtilis. Conclusions: The biosynthesized AgNPs showed significant antibacterial effect against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Shigella flexneri and Bacillus subtilis, so, it can be used in biomedical applications.