Abstract
This study investigates the development of nanoparticles derived from algal polysaccharides and evaluates their physicochemical properties, antioxidant capacity, and anti-inflammatory activity in comparison to their native counterparts. Polysaccharides extracted from Sargassum (SP), Ulva (UP), and Porphyra (PP) were subjected to dry-heating at various temperatures to form nanoparticles. The prepared polysaccharides and nanoparticles were characterized by molecular weight distribution, monosaccharide composition, yield, morphology, particle size, sulfate content, and functional group profiles, respectively. The nanoparticles were spherical in form, with diameter less than 500 nm. Furthermore, their polydispersity index (PDI) was observed to be lower than 0.4, and their zeta potentials ranged from -5 to -30 mV. Dry-heating above 210°C induced notable alterations in functional groups, while temperatures above 150°C significantly enhanced DPPH radical scavenging and Fe(2+) chelation activities. The nanoparticles showcased enhanced antioxidant and anti-inflammatory capabilities when juxtaposed with crude polysaccharides. Specifically, they led to a significant suppression of lipopolysaccharide (LPS)-induced generation of key pro-inflammatory molecules in macrophages. Importantly, the nanoparticles exhibited no cytotoxicity at concentrations below 1000 μg/mL. These findings suggest that algal polysaccharide-based nanoparticles, particularly those formed at higher temperatures, hold considerable potential as bioactive agents in therapeutic applications.