Title
Extraction, purification, characterization and antioxidant activities of polysaccharides from Cistanche tubulosa
Author
Wiejie Zhang, Jing Huang, Wei Wang, Qian Li, Yao Chen, Weiwei Feng, Daheng Zheng, Ting Zhao, Guanghua Mao, Liuqing Yang, Xiangyang Wu
Year
2016
Journal
International Journal of Biological Macromolecules
Abstract
An efficient ultrasonic-cellulase-assisted extraction (UCE) of Cistanche tubulosapolysaccharide (CTP) was established. The response surface methodology based on Box-Behnken Design was employed to further optimize extraction conditions. After quaternary ammonium salt precipitation, the polysaccharide of C. tubulosa was characterized by different techniques. The results showed that a maximum polysaccharide yield of 22.31 ± 0.45% was achieved at a pH of 5.2 for 31.5 min at 54.1 °C. Compared to hot water extraction, the yield of CTP in UCE and polysaccharide content increased to 44.96% and 70.13 ± 2.19%, respectively. There was no marked difference among polysaccharides extracted using different methods from the infrared spectrum. Ultrasonic-cellulase-assisted extraction polysaccharide showed a fibrous structure from scanning electron microscopy and was composed of rhamnose, mannose, glucose, and galactose in a molar ratio of 2.18:1:28.29:1.43 by gas chromatography. The circular dichroism results indicated that polysaccharides had a maximum positive peak around 210 nm with different peak values. The thermogravimetric analysis and differential scanning calorimetry were used to test the thermostability of CTP. Besides, CTP demonstrated appreciable antioxidant potential on antioxidant experiments in vitro. The results suggested that UCE is an effective method for CTP extraction and its polysaccharide showed appreciable antioxidant activity.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Biochemistry