Evaluation of brown macroalgae Sargassum as a source of active substances: a review of active substances

Sargassum seaweeds are widely distributed across temperate and tropical seas globally, boasting abundant biomass, an affordable price, high aesthetic value, and being rich in a diverse range of active substances. To assess the viability of Sargassum seaweeds as a source of active substances, a search was conducted on the Web of Science, Google Scholar and CNKI for relevant active substances derived from it. Additionally, the isolated active substances were categorized based on the species of Sargassum seaweeds. Finally, through cluster analysis using Citespace, the research trends regarding the active substances from Sargassum seaweeds were identified. Between 2014 and 2025, research on the active substances sourced from Sargassum seaweeds predominantly centered around polysaccharides and polyphenols. Fatty acids came next in focus, trailed by terpenes and phytosterols. The Sargassum species under study were mainly concentrated on 95 species. Among them, it was found that 5.38% of Sargassum seaweed, which included S. fusiforme, S. fulvellum, S. horneri, S. pallidum and S. wightii, contained nine or more active substances. However, in over 42% of the studied Sargassum seaweeds, fewer than two types of active substances were detected. Since 2004, active substances from approximately 40 species of Sargassum seaweeds have been isolated, and over 470 types of active substances have been identified. Among them, terpenoids accounts for around 30%, followed by polyphenols and polysaccharides, while other substances such as alkaloids and heterocyclic substances can make up to 20%. The authors also constructed the Database of Bioactive Substances from Sargassum seaweeds for searching active substances isolated from Sargassum seaweeds. CiteSpace analysis shows a clear hotspot shift: separating and purifying non-carbohydrate bioactive substances is a fast-growing core direction. Previously, polysaccharides dominated due to easy extraction and mature activity research. However, with advanced separation technologies and exploration of "niche" substances, non-carbohydrates (terpenoids, alkaloids, etc.) now show great potential, promising to break research bottlenecks. This study offers theoretical and practical support for Sargassum application, guiding product innovation in pharmaceuticals, food, and cosmetics.