Structure and antioxidative property of a polysaccharide from an ammonium oxalate extract of Phellinus linteus

摘要

In this paper, the novel polysaccharide PL-A11 was purified from an ammonium oxalate extract of Phellinus linteus mycelia. Its physicochemical properties, structural characteristics, and antioxidant activities were investigated. Results showed that PL-AI I had a weight-average molecular weight (M-w) of 13.8 kDa and was mainly composed of arabinose, xylose, mannose, and glucose in a molar ratio of 1.1:1.3:1.0:6.6. The backbone of PL-A11 was composed of (1 -> 4)-alpha-D-glucopyranosyl, (1 -> 2)-alpha-D-xylopyranosyl, and (1 -> 3)-alpha-D-arabinofuranosyl residues, whereas the (1 -> 6)-alpha-D-mannopyranosyl residues formed branches at the O-2 position with 1-linked-alpha-D-glucopyranosyl terminal residues. From the antioxidative activity tests in vivo, the administration of PL-Al I obviously enhanced the activity of antioxidant enzymes and significantly reduced the level of malondiadehyde (MDA) in the serum and liver of n-galactose-treated aging mice in a dose-dependent manner, as well as effectively stimulated the immune system of aging mice. These findings implied that PL-A1 I could be developed as a potential antioxidant for applications in the functional food, pharmaceutical, cosmetic or nutraceutical industries. (C) 2016 Elsevier B.V. All rights reserved.