Colloidal and structural perspectives on seaweed-derived bioactives: Extraction techniques and emerging applications

The seaweeds, frequently labeled as macroalgae, can be classified into three vital groups: Chlorophyta (green algae), Phaeophyceae (brown algae), and Rhodophyta (red algae). Marine macroalgae serve as plentiful reservoirs of bioactive elements, comprising polysaccharides, proteins, fats, crucial minerals, vitamins, phenolic substances, and pigments, potentially influencing many sectors. Agar, alginate, carrageenan, fucoidan, polyphenols, and peptides have remarkable roles in promoting health, fighting inflammation, combating microbes, reducing obesity, and preventing cancer, making them essential for enhancing wellness, averting illness, creating functional foods, and developing beauty products. This review examines the extraction of these bioactive substances, which has increasingly employed novel methodologies due to their considerable advantages, such as eco-friendliness, expedited processes, enhanced sustainability, and overall superior efficiency compared to conventional or traditional techniques. To achieve optimal efficiency outcomes for the targeted bioactive compounds, it is imperative to optimize the parameters of novel methods for each specific approach. Furthermore, this investigation illuminates the imaginative applications of seaweed-derived substances, showcasing their significant evolution while emphasizing their structure and prospective applications within the food sector; these seaweeds serve as a basis for developing fertilizers, biofuels, biostimulants, bioplastics, cosmetics, pharmaceuticals, and other biotechnological products, including alginate-based innovations. To enhance understanding of the medicinal potential of seaweeds, recent advancements and challenges pertaining to bioavailability are scrutinized within a pharmaceutical context. Seaweeds are vital for restoring contaminated water and soil, supporting efforts to reduce climate change and encouraging a circular economy, which points to the pressing requirement for further investigation and innovation to fully exploit their broad uses.