Seaweed-Derived Bioactives: A Promising Source of Novel Therapeutics

The marine environment provides bioactive natural products with unique structures that are absent in terrestrial compounds. This review aims to provide a thorough overview of key studies on bioactives derived from seaweeds. It focuses on their potential to address common diseases such as microbial infections, diabetes, oxidative stress, inflammation, viral infections, cancer, immune disorders, and Alzheimer's disease as well as their potential use in drug delivery systems. The bioactive compounds found in seaweeds belong to various chemical classes, with the largest proportion being polysaccharides, lipids, proteins, phenolics, pigments, terpenoids, alkaloids, and sterols. These compounds possess significant pharmacological potential. This review also highlights the diverse sources of these compounds, including various seaweed species belonging to different taxonomic groups. In addition, it discusses the different techniques of extraction, purification, characterization, and evaluation of biological activities. Furthermore, particular attention is given to modern extraction approaches, which enhance economic feasibility and environmental sustainability while reducing extraction time and improving the yield of bioactive constituents. Despite the significant advances in extraction technologies and the growing recognition of the therapeutic potential of seaweed bioactives, several obstacles still hinder the efficient utilization and large-scale application of these compounds. Challenges include overharvesting, climate impacts, high production costs, complex extraction methods, and limited genomic data. To address these challenges, advancing research on seaweed-derived bioactives requires sustainable farming, ecofriendly extraction methods, genetic engineering, and clinical studies. In addition, collaboration among different sectors and raising public awareness are strongly recommended. Building on these recommendations, future perspectives can guide the development of seaweed-derived therapeutics. In this context, research should focus on synthesizing derivatives to enhance pharmacological properties, exploring structure—activity relationships, and expanding applications in biotechnology. Moreover, the integration of computational tools and omics techniques can further advance these studies and accelerate the discovery of novel compounds.