The investigation of nanotechnology is currently one of the most exciting fields in materials science. The subject of nanotechnology has made tremendous strides in recent years, with a variety of approaches created to produce nanoparticles of a given form and size depending on particular requirements. Nanotechnology is described as the production, characterization, study and use of nanoscale substances for the advancement of science. As a type of chemical defence, ascidians produce a lot of secondary metabolites. Attempts have been made to synthesise silver nanoparticles from Phallusia nigra. The antioxidant activity of silver nanoparticles from Phallusia nigra was evaluated based on their ability to scavenge DPPH free radicals. Silver nanoparticles from Phallusia nigra exhibited significant, dose-dependent scavenging activity with 48.38%, 56.45%, 69.35%, 75.64 % and 84.51% at concentrations of 20, 40, 60, 80 and 100 µg/ml respectively. The scavenging activity of AgNPs produced from Didemnum psammatode was substantial, with values of 30.48%, 39.83%, 50.80%, 64.03 % and 67.74% at 20, 40, 60, 80 and 100 µg/ml concentrations respectively.