Valorisation de l’algue invasive Rugulopteryx okamurae et de quelques types d’algues en produits cosmétiques

Abstract

This thesis is part of a sustainable approach to the valorization of marine resources, particularly seaweeds. It focuses on Rugulopteryx okamurae, an invasive brown alga found along the Atlantic and Mediterranean coasts, whose proliferation raises ecological and socio-economic concerns. Although this species is not yet used in cosmetic product manufacturing, its potential as a natural raw material is explored in this study. The first part of the study examines the valorization of several types of seaweed already recognized and used in cosmetics, particularly for artisanal soap production. Algae such as Cystoseira foeniculacea, Ulva lactuca, and Chondrus crispus are known for their beneficial effects on the skin: moisturizing, antioxidant, soothing, and revitalizing. Their richness in polysaccharides, minerals, and vitamins makes them highly valued ingredients in cosmetic formulations. The second part investigates the chemical and biological characteristics of Rugulopteryx okamurae to assess its potential future integration into cosmetic products, especially soaps. Although its current use is limited, preliminary analyses suggest the presence of promising bioactive compounds. Valorizing this seaweed could thus offer an innovative solution to reduce its environmental impact while creating new economic opportunities. This work aims to establish a connection between ecological research, cosmetic innovation, and sustainable development.