Purification, Physicochemical Properties, and Antioxidant Activities of Two Low-Molecular-Weight Polysaccharides from <i>Ganoderma leucocontextum</i> Fruiting Bodies
Xiong Gao,
Jiayi Qi,
Chi-Tang Ho,
Bin Li,
Yizhen Xie,
Shaodan Chen,
Huiping Hu,
Zhongzheng Chen,
Qingping Wu
Affiliations
Xiong Gao
State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Safety and Health, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
Jiayi Qi
Department of Bioengineering, College of Food Science, South China Agricultural University, 483 Wushan Street, Tianhe District, Guangzhou 510642, China
Chi-Tang Ho
Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, NJ 08901, USA
Bin Li
Department of Bioengineering, College of Food Science, South China Agricultural University, 483 Wushan Street, Tianhe District, Guangzhou 510642, China
Yizhen Xie
State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Safety and Health, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
Shaodan Chen
State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Safety and Health, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
Huiping Hu
State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Safety and Health, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
Zhongzheng Chen
Department of Bioengineering, College of Food Science, South China Agricultural University, 483 Wushan Street, Tianhe District, Guangzhou 510642, China
Qingping Wu
State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Safety and Health, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
Two low-molecular-weight polysaccharides (GLP-1 and GLP-2) were purified from Ganoderma leucocontextum fruiting bodies, and their physicochemical properties and antioxidant activities were investigated and compared in this study. The results showed that GLP-1 and GLP-2 were mainly composed of mannose, glucose, galactose, xylose, and arabinose, with weight-average molecular weights of 6.31 and 14.07 kDa, respectively. Additionally, GLP-1 and GLP-2 had a similar chain conformation, crystal structure, and molecular surface morphology. Moreover, GLP-1 exhibited stronger antioxidant activities than GLP-2 in five different assays: 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), hydroxyl radical, superoxide anion radical, ferric reducing antioxidant power (FRAP), and oxygen radical antioxidant capacity (ORAC). The main linkage types of GLP-1 were found to be →4)-α-D-Glcp-(1→, →4)-β-D-Glcp-(1→, →3)-β-D-Glcp-(1→, →6)-β-D-Galp-(1→, →6)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, and Glcp-(1→ by methylation analysis and nuclear magnetic resonance (NMR) spectroscopy. In addition, GLP-1 could protect NIH3T3 cells against tert-butyl hydroperoxide (tBHP)-induced oxidative damage by increasing catalase (CAT) and glutathione peroxidase (GSH-Px) activities, elevating the glutathione/oxidized glutathione (GSH/GSSG) ratio, and decreasing the malondialdehyde (MDA) level. These findings indicated that GLP-1 could be explored as a potential antioxidant agent for application in functional foods.
