Isolation, purification, structural characterization, and antitumor activity of Gynura divaricata polysaccharides
Ping Chen, Xiao Tan, Liuyue Xiao, Zan Gong, Xiangxiang Qin, Jing Nie, Zhu Hua, Shian Zhong
Abstract
In this study, a water-soluble, homogeneous polysaccharide , GDPs-1, was isolated from Gynura divaricata and purified. It was subsequently subjected to structural characterization and biological activity assessment. Structural characterization revealed that GDPs-1 was mainly composed of glucose, galactose , and arabinose , with a molecular weight of 55.1 kDa. Its main structural backbone was →[4)-α-D-Glcp-(1] 22 → 4)-α-D-Glcp-(1 → 4)-α-D-Glcp-(1 → [4)-β-D-Galp-(1] 11 →, with two additional branched structures. In vitro experiments demonstrated that GDPs-1 induced cancer cell apoptosis, caused cell cycle blockade, increased the Bax/Bcl-2 protein ratio, attenuated epithelial–mesenchymal transition, and activated caspase-3 protein in carcinoma cells, thereby exerting antitumor effects on tumor cells without affecting the growth of normal cells. Therefore, GDPs-1 may be further explored as a novel medicine to treat lung and liver cancer.