Evaluation of the Immunogenicity of Sargassum fluitans, an Invasive Brown Seaweed in the Coastal Zone of Côte d'Ivoire, in Rabbits

Abstract

Sargassum fluitans is an invasive brown seaweed found in coastal areas of Côte d'Ivoire, whose presence causes numerous problems for local communities. The aim of this study is to contribute to the development of this species by evaluating its immunogenic potential in rabbits. The study made it possible to extract and identify, through phytochemical sorting, the active ingredients contained in the Total Aqueous Extract (TAE), which are polyphenols and tannins. The injection of TAE in increasing doses to rabbits showed that Sargassum fluitans stimulates immunity by inducing an increase in immune cell levels. Indeed, the results of blood tests on the rabbits showed that the immune defense cells, composed mainly of white blood cells, lymphocytes, and neutrophils, underwent various changes over time (from D0 to D8) after injection of the product. The different doses of 5 mg/mL, 15 mg/mL, 25 mg/mL, and 9‰ NaCl (controls) showed relatively low results. However, the 25 mg/mL dose proved to be the most interesting. Indeed, the number of Gb and Ne on D2 was significantly higher (p < 0.001) than on D0, confirming rapid and strong stimulation. Sargassum fluitans could be an excellent candidate for further studies with a view to developing an immunostimulant, thereby contributing to the genuine promotion of these brown algae.