Green synthesis of silver nanoparticles using Fagopyrum esculentum starch: antifungal, antibacterial activity and its cytotoxicity

Silver nanoparticles (AgNPs) have been synthesized using Fagopyrum esculentum starch as a stabilizing and reducing agent. This reaction was carried out in an autoclave at 15 psi, 121 degrees C for 20 min. UV-visible spectrum of the colloidal nanoparticles showed the surface plasmon absorption band with maximum absorbance at 418 nm. Interaction between functional groups present in the starch and nanoparticles were analyzed by Fourier-transform infrared spectroscopy (FTIR). Size of the synthesized nanoparticles was found to be in the range of 20-30 nm, as revealed from transmission electron microscopy (TEM). The X-ray diffraction analysis revealed the face-centred cubic (fcc) geometry of silver nanoparticles. The nanoparticles were found to be good antifungal agents against Aspergillus niger. The antibacterial activity of the nanoparticles was also studied. The nanoparticles showed higher inhibitory activity against Gram-negative bacteria (Escherichia coli) than the Gram-positive bacteria (Staphylococcus aureus). These results thus show that F. esculentum starch stabilized AgNPs could be used as a promising antimicrobial agent against bacteria the fungi In vitro cytotoxicity assessment of starch stabilized AgNPs has shown no significant cytotoxic effect on human cervical carcinoma cells lines (HeLa) by MTT assay and AgNPs concentration at 200 ug/ml of showed 86% cell viability.