Biochemical Characterization and Metabolic Evaluation of the Invasive Brown Algae Sargassum muticum from the Moroccan Atlantic Coast

Sargassum muticum is an invasive brown macroalga that has rapidly expanded along the Moroccan Atlantic coast, posing ecological challenges while representing an abundant marine biomass with potential biotechnological value. This study investigated the biochemical composition and metabolic properties of Moroccan S. muticum through compositional analysis, in vivo metabolic evaluation, and molecular docking. Proximate analysis revealed a carbohydrate-rich composition with moderate protein content, together with photosynthetic pigments and nutritionally relevant minerals. In a cafeteria diet-induced rat model, dietary supplementation with S. muticum significantly attenuated body weight gain, improved adiposity-related indices, reduced serum total cholesterol, triglycerides, LDL cholesterol, and C-reactive protein levels, and increased HDL cholesterol. To obtain mechanistic insight, molecular docking analysis was performed using representative phlorotannins reported from Sargassum species. Among the compounds evaluated, dieckol showed the highest docking scores toward key metabolic targets, including AMP-activated protein kinase and peroxisome proliferator-activated receptor gamma. Although these in silico findings do not demonstrate biological activation, they provide preliminary mechanistic support for the observed in vivo effects. Overall, the results highlight the potential of S. muticum for sustainable valorization as a functional marine bioresource.