Extraction Optimization, Purification, Antioxidant Activity, and Preliminary Structural Characterization of Crude Polysaccharide from an Arctic Chlorella sp.

• Published in: Polymers
• Main Authors: Hong Song, Meilin He, Chuankun Gu, Dong Wei, Yuqi Liang, Junmei Yan, Changhai Wang
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2018
• Subjects: arctic Chlorella sp; polysaccharide; antioxidant activity; preliminary structural characterization; Organic chemistry; QD241-441; Arctic
• Online Access: https://doi.org/10.3390/polym10030292; https://doaj.org/article/f6673ab8cfe94842aab06fc5b1c5165d

The arctic strain of Chlorella sp. (Chlorella-Arc) exists in the coldest and driest arctic ecosystems, and it is a new resource of active polysaccharides. The extraction of crude polysaccharide from Chlorella-Arc was optimized using the response surface methodology. A crude polysaccharide yield of approximately 9.62 ± 0.11% dry weight was obtained under these optimized conditions. Three fractions (P-I, P-II, and P-III) were present after purification by 2-diethylaminoethanol Sepharose Fast Flow and Sephadex G-100 chromatography. The P-IIa fraction demonstrated significant antioxidant activities. Moreover, P-IIa was an α- and β-type heteropolysaccharide with a pyran group and contained variable amounts of rhamnose, arabinose, glucose, and galactose based on fourier-transform infrared spectroscopy, high-performance liquid chromatography, and 1H and 13C nuclear magnetic resonance imaging. Production of high amounts of polysaccharide may allow further exploration of the microalgae Chlorella-Arc as a natural antioxidant.