<p>Polysaccharides are complex macromolecules found in plants, algae, fungi and microorganisms. Their unique structural features and wide range of functional properties have attracted increasing scientific attention. These biopolymers exhibit diverse biological and physicochemical characteristics that make them valuable in both food and health-related applications. This review discusses recent progress in extraction techniques including enzymatic, ultrasonic and green eco-friendly approaches, which aim to improve yield and purity. The physicochemical properties of polysaccharides such as molecular weight, branching and glycosidic linkages determine their effectiveness as thickeners, stabilizers and gelling agents in food systems. In addition to their technological functions, polysaccharides show significant bioactivities including immunomodulatory, antioxidant and antidiabetic effects. However, challenges remain regarding bioactivity consistency, structural characterization and scalable extraction. Overall, this paper highlights the potential of polysaccharides as sustainable components in functional foods and nutraceuticals, emphasizing their importance in promoting global health and nutritional well-being.</p>