Synthesis of ZnO nanoparticles using insulin-rich leaf extract: Anti-diabetic, antibiofilm and anti-oxidant properties.

TLDR: The novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus.

Abstract: Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC–MS) and proton nuclear magnetic resonance ( 1 H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci -ZnO NPs ( C. igneus - coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci -ZnO NPs were specified using UV–visible spectroscopy, FTIR, XRD, and TEM. Ci -ZnO NPs was authenticated by UV–Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci -ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci -ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci -ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci -ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 μg/ml. The Ci -ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans , Lysinibacillus fusiformis , Proteus vulgaris , and Vibrio parahaemolyticus . Additionally, the Ci -ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ± 0.005 %) at a concentration of 200 μg/ml.