Greener pathway toward the synthesis of lichen-based ZnO@TiO2@SiO2and Fe3O4@SiO2nanocomposites and investigation of their biological activities

A green way is introduced to biosynthesis of ZnO@TiO2@SiO(2)and Fe3O4@SiO(2)nanocomposites using the bioactive potential ofLecanora muralis(LM) lichen. UV-Vis spectroscopy and GC-Mass analysis of the lichen show the presence of various bioactive constituents inside the lichen aqueous extract. The XRD, SEM, EDS, and elemental mapping techniques revealed the well fabrication of biosynthesized nanostructures. Also, investigation of antibacterial and antifungal activities of nanostructures demonstrated that green synthesized nanostructures have a very good antibacterial ability againstStaphylococcus aureus,Escherichia coli,Pseudomonasspp. andCandidaspp. pathogenic bacteria, and fungi but no antifungal activity toward theAspergillus flavus,Aspergillus niger, andAspergillus terrusfungi species.