Cannabis polysaccharides (CPs): Extraction methods, structural characteristics, biological activities and structure-function relationship: A review

Cannabis polysaccharides (CPs) have attracted growing interest due to their diverse structures and potential bioactivities. This review consolidated current knowledge on the CPs extraction, their characterization, molecular properties and biofunctional potentials. Composition of the CPs varied by plant part, cultivar and origin with most studies focused on seed derived polysaccharides. Extraction methods, particularly the hot water and enzyme assisted extractions differ in temperature, duration and solid-liquid ratio influencing the final yield and molecular integrity. Advanced analyses such as HPAEC-PAD, HPSEC, GC-MS and FT-IR revealed monosaccharides such as mannose, glucose, galactose, glucuronic acid and galacturonic acid, along with proteins, sulfates and uronic acids. The reported molecular weight range was 4.21 to 864.17 kDa representing both low and high Mw fractions. The CPs were reported with antioxidant and antiaging activities which are often mediated via the Nrf2/Keap1-ARE pathway. These activities are shaped by the Mw and sugar composition with low-Mw fractions having enhanced antioxidant activity. Rare sugars and sulfated residues further enhanced the bioactivity suggesting specialized therapeutic applications. Emerging evidences also pointed to the roots, leaves and hemp residues as underexplored sources with potential for novel bioactivities. This review underscores the structural diversity of CPs, the effect of extraction methods on yield and biofunctional properties, their key bioactivities and the underlying mechanisms. Collectively, these insights provide a comprehensive foundation and research roadmap for advancing the CPs in pharmaceutical, nutraceutical and functional food applications.