Antioxidant and Anticoagulant Activities of Sulfated Polysaccharides from the Edible Seaweed Gracilaria birdiae
aPTT assay; total capacity antioxidant; sonication; proteolysis; red seaweed.
The sulfated polysaccharides-rich extract from the edible red seaweed Gracilaria birdiae were obtained usingfive different conditions (GB1: Water; GB1s: Water/sonication; GB1sp: Water/sonication/proteolysis; GB2s: NaOH/sonication; GB2ps: NaOH/sonication/proteolysis. The yield increased in the following order GB2ps>GB1ps>GB2s>GB1s>GB1. However, the amount of SP extracted increased in different way GB2ps>GB1>GB1ps>GB1s>GB2s. Infrared and electrophoresis analysis showed that all conditions extracted the same SP. In addition, monosaccharide composition showed that ultrasound promotes the extraction of other polysaccharides than SP. In PT test, which evaluates the extrinsic coagulation pathway, all samples showed no anticoagulant activity. While in the aPTT test, which evaluates the intrinsic coagulation pathway, all samples showed anticoagulant activity, except GB2s. The aPTT activity decreased in the order of GB1ps>GB2ps>GB1>GB1s>GB2s. Total capacity antioxidant (TCA) of the sulfated polysaccharides-rich extracts was also affect by extract conditions, since GB2s and GB1showed lower activity in comparison to the other extract. In conclusion, the conditions of SP extraction influence their biological activities and chemical composition. The data showed NaOH/sonication/proteolysis was the best condition to extract anticoagulant and antioxidant SPs from Gracilaria birdiae.