Characterization of Three Brown Algae Bifurcaria Bifurcata, Cystoseira Gibraltarica and Fucus Spiralis

Abstract

In recent years, scientists have become interested in marine macroalgae, which represent a rich source of bioactive substances. These molecules are characterized by a multitude of forms and structures and have several biological activities. The present study aims to characterize the three brown algae Bifurcaria bifurcata, Cystoseira gibraltarica and Fucus spiralis. These were collected in the region of Cap Ghir north of Agadir. The results obtained show that the mineral analyses of the extracts of F. spiralis, B. bifurcata and C. gibraltarica highlighted the richness of these brown algae in macroelements (Ca, K, P, Na, N). Concerning the total sugar content of C. gibraltarica shows a significant difference with the other two algae B. bifurcata and F. spiralis and has the highest content. For the protein content, no significant difference was recorded between the three algal extracts. Indeed, the aqueous extract of C. gibraltarica has a protein content of 48.44 mg/g DM, the aqueous extract of F. spiralis showed an average protein content of 45.55 mg/g DM, and that of the aqueous extract of B. bifurcata is 44.03 mg/g DM. The three brown algae C. gibraltarica, B. bifurcata and F. spiralis have consistent levels of organic matter. F. spiralis and C. gibraltarica have significantly equivalent organic matter contents (73.74 and 73.44 g/100g DM, respectively). In this study, the analysis of total phenols shows that F. spiralis presents a significant difference with the two other algae and has the highest content (7.2 µg/mg dry matter). In general and whatever the method of flavonoid determination, the flavonoid content of the three algae is significantly different. The methanolic extract of F. spiralis shows the highest flavonoid content, followed by B. bifurcata. While the lowest content is presented with the methanolic extract of C. gibraltarica. The results of the antioxidant potential using DPPH reveal a significant difference between the three algae. Indeed, the extracts of the analyzed algae present an antioxidant activity varying between 33.61 and 88.3%, with a high antioxidant potential (88.3%) for F. spiralis and thus an important capacity to trap the DPPH radical. These three studied brown algae represent a promising source of biologically active molecules that can be used in several fields such as organic agriculture.