Biochemical and heavy metals composition of the invasive seaweed Sargassum muticum (Yendo) according to season and sites along Moroccan Atlantic Coast

Abstract

AbstractSince 2012 Moroccan Atlantic coast have witnessed the introduction of the brown alien seaweedSargassum muticumwith a high invasive potential presenting environmental and economic risks. This study evaluates, for the first time, the effect of seasons and location on biochemical composition ofS. muticum. Proteins, carbohydrates, lipids, pigments, minerals, and heavy metals were studied during four seasons from spring 2019 to autumn 2020 in four different sites along the Moroccan Atlantic coast (El Jadida, Saada (SA), Sidi Bouzid (SB), Moulay Abdallah (MA) and Jorf Lasfar (JL)). MA present highest proteins content (12.5% dw) during spring and highest levels of lipids and carbohydrates content during summer (1.8% dw and 41.5% dw respectively). Highest chlorophyll a content was found in JL and MA site with (21.6 and 21.45 mg ml− 1respectively) during winter. Maximum chlorophyll c and carotenoids was found at SA with (2.27 and 9.71 mg ml− 1respectively) during winter. In all locations and during all seasons, the mineral profile was rich in essential minerals such as Mg, Mn, Zn, Fe, Se and Li. Levels of toxic metals Al and Pb were lower than in previous studies whereas Cd and As turn to be slightly higher than the legislations limits for dry seaweeds. Therefore, in this context, some strategies ofS. muticumvalorisation should be favoured such as bioenergy, bioplastic or biostimulant over others such as human food and animal feed.