Carrageenan of Red Algae Eucheuma gelatinae: Extraction, Antioxidant Activity, Rheology Characteristics, and Physicochemistry Characterization

Carrageenan is an anionic sulfated polysaccharide that accounts for a high content of red seaweed Eucheuma gelatinae. This paper focused on the extraction, optimization, and evaluation of antioxidant activity, rheology characteristics, and physic-chemistry characterization of beta-carrageenan from Eucheuma gelatinae. The extraction and the optimization of beta-carrageenan were by the maceration-stirred method and the experimental model of Box-Behken. Antioxidant activity was evaluated to be the total antioxidant activity and reducing power activity. The rheology characteristics of carrageenan were measured to be gel strength and viscosity. Physic-chemistry characterization was determined, including the molecular weight, sugar composition, function groups, and crystal structure, through GCP, GC-FID, FTIR, and XRD. The results showed that carrageenan possessed antioxidant activity, had intrinsic viscosity and gel strength, corresponding to 263.02 cps and 487.5 g/cm(2), respectively. Antioxidant carrageenan is composed of rhamnose, mannose, glucose, fucose, and xylose, with two molecular weight fractions of 2.635 x 10(6) and 2.58 x 10(6) g/mol, respectively. Antioxidant carrageenan did not exist in the crystal. The optimization condition of antioxidant carrageenan extraction was done at 82.35 & DEG;C for 115.35 min with a solvent-to-algae ratio of 36.42 (v/w). At the optimization condition, the extraction efficiency of carrageenan was predicted to be 87.56 & PLUSMN; 5.61 (%), the total antioxidant activity and reducing power activity were predicted to 71.95 & PLUSMN; 5.32 (mg ascorbic acid equivalent/g DW) and 89.84 & PLUSMN; 5.84 (mg FeSO4 equivalent/g DW), respectively. Purity carrageenan content got the highest value at 42.68 & PLUSMN; 2.37 (%, DW). Antioxidant carrageenan from Eucheuma gelatinae is of potential use in food and pharmaceuticals.

Automated summary

This study focused on the extraction, optimization, and evaluation of antioxidant activity and physic-chemistry characterization of beta-carrageenan from Eucheuma gelatinae. The results showed that the carrageenan possessed antioxidant activity, intrinsic viscosity, and gel strength. The optimized extraction conditions were determined to be 82.35°C for 115.35 minutes with a solvent-to-algae ratio of 36.42 (v/w).