Regioselective syntheses of sulfated porphyrans from Porphyra haitanensis and their antioxidant and anticoagulant activities in vitro

Porphyran extracted from Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent antioxidant activities. In this study, we prepared porphyran and alkali-treated porphyran and their derivatives, sulfated porphyran. And then we evaluated their antioxidant and anticoagulant activities in vitro and characterized the relationship between activities and chemical characteristics. The activities were strongly dependant on the degree of sulfation and the position of sulfate. In this study, the antioxidant activities mainly depend on degree of substitution, and the anticoagulant activities mainly depend on the position of sulfate. Further studies are needed to improve our understanding of antioxidant and anticoagulant activities mechanism.