Green Technology Enabled Graphene Oxide Reduction Using Justichia wynaadensis Extract and Assessment of In Vitro Antioxidant and Antibacterial Activity
Graphene oxide (GO) was reduced using Justichia wynaadensis aqueous extract. GO was mixed with extract and refluxed at 100 °C for 10 h to obtain reduced GO. PXRD of rGO showed broad peak at 2 = 25° and disappearance of 2 = 9.75° after refluxing which indicates efficient removal of oxygen containing groups. SEM images of rGO showed flaky structures typical of retainment of GO structure with folded curtains like appearance of rGO. UV-vis spectra demonstrated absorption band ~300 nm and shoulder at 400 nm corresponding to π–π* transitions and C ═ O bonds respectively indicating that rGO is red shifted due to decrease in oxygen functional groups. rGO showed potent antibacterial activity against Staphylococcus aureus, upon testing against S. aureus and P. aeruginosa. It showed 67% radical scavenging against DPPH at 500 μg/mL concentration. In conclusion, J. wynaadensis aqueous extract efficiently removed oxygen functionalities from GO surface with significant biological activities.