Facile green synthesis of gold nanoparticles from marine algae Gelidiella acerosa and evaluation of its biological Potential

In this present research, the Gold nanoparticles (GA-AuNPs) produced from Gelidiella acerosa , marine algae using green synthesis method was evaluated for its antidiabetic, antibacterial and antioxidant activity. Well-developed GA-AuNPs were effectively characterized using advanced analytical instruments like HRTEM, UV–visible, SEM and XRD. This analysis exposed GA-AuNPs to be present with spherical, hexagonal structure and crystalline nature. The average size of GA-AuNPs particles was estimated to lie between 5.81 nm to 117.59 nm by using Debye–Scherer equation. The enzyme inhibitory property of (IC 50 ) of G. acerosa aqueous extract and synthesized gold nanoparticles from G. acerosa against α amylase and α- glucosidase enzyme was found to be 2.1 ± 0.01, 3.7 ± 0.01 µg/mL and 2.8 ± 0.02, 4.1 ± 0.01, respectively. Further antioxidant assessment of GA-AuNPs were examined using DPPH and FRAP assays, the results exhibited that the strong antioxidant activity were observed in all the concentrations when compared with standard. Finally antibacterial activity was evaluated the GA-AuNPs against gram positive and gram negative bacteria, the strong antibacterial activity was observed in both the bacterial strains when compared with standard antibiotic. The GA-AuNPs from marine algae was exhibited to be strong inhibitory activity against alpha amylase and alpha glucosidase enzyme, antioxidant activity and antibacterial activity, these GA-AuNPs are projected to have potential biological applications.