Bioengineered gold nanoparticles from marine seaweedAcanthophora spiciferafor pharmaceutical uses: antioxidant, antibacterial, and anticancer activities

In this study, we report a green synthesis of pharmaceutically active gold nanoparticles from marine red algaAcanthophora spiciferaby the reduction of chloroauric acid. The formation ofA. spicifera-mediated gold nanoparticles (As-AuNPs) was characterized by several analytical techniques. The crystalline and face-centered cubic (fcc) structure were confirmed by X-ray diffraction (XRD) analysis. Electron microscopy results confirmed that As-AuNPs were spherical and the average size of particles was < 20 nm. As-AuNPs hold a significant level of antioxidant activities thanA. spiciferaextract. As-AuNPs exhibited the highest antibacterial activity againstVibrio harveyithanStaphylococcus aureusat 100 mu g/ml. Furthermore, As-AuNPs exhibited the utmost cytotoxicity against human colon adenocarcinoma (HT-29) cells and registered the half-maximal inhibitory concentration (IC50) at 21.86 mu g/ml. These findings authenticated that the synthesized As-AuNPs possess a broad spectrum of biological activities, and it can be effectively applied in the field of aquaculture and biomedical application.