κ-Carrageenan is liner sulfated galactans extracted from the extracellular matrixof red marine algae. Sulfated oligosaccharides and their derivates prepared fromκ-carrageenan have diverse biological and physiological activities, includingantitumor, anti-HIV, immunoregulation, and viral inactivation activities. Thus,κ-carrageenan oligosaccharides show potential use in functional foods andpharmaceutical areas. Undoubtedly, degrading carrageen with a specific enzymecalled carrageenase, which features high subs...