Bio-waste eggshell membrane assisted synthesis of NiO/ZnO nanocomposite and its characterization: Evaluation of antibacterial and antifungal activity

Optical and biological properties of MgO/ZnO nanocomposite derived via eggshell membrane: a bio-waste approach

A novel synthesis of MgO/ZnO nanocomposite using a template, namely an eggshell membrane (ESM) was attempted. The nanocomposite was characterized by XRD, UV-visible, FTIR, Raman, DLS (zeta potential and particle size distribution), FESEM with EDX, and HRTEM analysis. The presence of periclase cubic MgO (space group Fm3m) and hexagonal wurtzite ZnO (space group P63mc) structures was verified by the XRD results. The average crystallite size of the MgO/ZnO nanocomposite was equal to 9.43 nm. The nanocomposite exhibited an on-set of absorbance close to 300 nm. From the taucs plot, the bandgap of the composite was calculated, and it was equal to 3.63 eV. The FTIR spectrum of the composite showed Mg-O stretching vibration at 455 cm^-1 and that of Zn-O at 564 cm^-1. The zeta potential and the particle size distribution of the nanocomposite were equal to - 35.5 mV and 176.1 nm. The FESEM images of the nanocomposite appeared as an aggregated honeycomb with a cubic and hexagonal structure. The EDX analysis showed the presence of Mg (23.65 atom%), Zn (27.95 atom%), and O (48.40 atom%). The antibacterial and antifungal activities of the nanocomposite were investigated using the agar-well diffusion method. The antibacterial activity exhibited the highest zone of inhibition for Bacillus subtilis (25 ± 0.41 mm) and Shigella dysenteria (25 ± 0.19 mm), whereas the antifungal activity showed the highest zone of inhibition for Aspergillus terrus (27 ± 0.25 mm). The MIC value of the nanocomposite was equal to 9.37 (µg/mL) for all the bacteria. Hence, it is verified that the present MgO/ZnO nanocomposite could very well be used to treat bacterial and fungal infections.

Biosynthesis of TiO2 nanoparticles by Caricaceae (Papaya) shell extracts for antifungal application

Titanium dioxide nanoparticles (TiO₂ NPs) were prepared by Caricaceae (Papaya) Shell extracts. The Nanoparticles were analyzed by UV–Vis spectrums, X-ray diffractions, and energy-dispersive X-rays spectroscopy analyses with a scanning electron microscope. An antifungal study was carried out for TiO₂ NP in contradiction of S. sclerotiorums, R. necatrixs and Fusarium classes that verified a sophisticated inhibitions ratio for S. sclerotiorums (60.5%). Germs of pea were individually preserved with numerous concentrations of TiO₂ NPs. An experience of TiO₂ NPs (20%, 40%, 80% and 100%), as well as mechanisms that instigated momentous alterations in seed germinations, roots interval, shoot lengths, and antioxidant enzymes, were investigated. Associated with controls, the supreme seeds germinations, roots and plant growth were perceived with the treatments of TiO₂ NPs. Super-oxide dis-mutase and catalase activities increased because of TiO₂ NPs treatments. This advocates that TiO₂ Nanoparticles may considerably change antioxidant metabolisms in seed germinations.