Structural modification of laminaran for enhanced bioactivity: Advances, mechanisms, and applications - A review

Laminaran is a neutral β-(1→3)/(1→6)-glucan polysaccharide derived from brown algae, recognized for its antioxidant, immunomodulatory, and anticancer properties. However, its native form exhibits limitations such as poor solubility, restricted functional groups, and low bioavailability, which constrain its practical applications. This review provides a comprehensive overview of laminaran's structural characteristics, modification strategies, and mechanisms underlying bioactivity enhancement. Chemical modifications, including sulfation, oxidation, carboxymethylation, and amination, introduce functional groups that improve solubility, molecular interactions, and receptor binding affinity. Enzymatic and physical approaches further enhance biological performance by reducing molecular weight and modifying structural conformation, thereby increasing accessibility and activity. In addition, hybrid strategies that integrate enzymatic pre-treatment with targeted chemical modification have demonstrated significant potential in producing multifunctional derivatives with enhanced antioxidant, anticancer, and immunostimulatory effects. These advancements have expanded the applicability of modified laminaran in diverse fields, including drug delivery, wound healing, tissue engineering, functional foods, and environmental remediation. Despite these promising developments, challenges related to structural heterogeneity, process optimization, and clinical validation remain. Future research should focus on regioselective modification, computational design, and sustainable bioprocessing approaches to facilitate the scalable production and practical utilization of laminaran-based biomaterials.