Original scientific paper
Production Optimization,Molecular Characterization and Biological Activities of Exopolysaccharides from Xylaria nigripes
Y.P. Ma
; China Tobacco Henan Industrial Co. Ltd, Zhengzhou, Henan, 450016, P.R.China
D.B. Mao
; College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, 450002, P.R.China
L.J. Geng
; bCollege of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, 450002, P.R.China
W.Y. Zhang
; bCollege of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, 450002, P.R.China
Z. Wang
; bCollege of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, 450002, P.R.China
C.P. Xu
; bCollege of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan, 450002, P.R.China
Abstract
The optimal culture conditions of exopolysaccharides (EPS) production in submerged culture medium by Xylaria nigripes were determined using orthogonal matrix method. The optimal medium (per liter) EPS was 60.0 g L–1 maltose, 1.0 g L–1 peptone,
5 mmol L–1 KH2PO4, and initial pH 7.0 at 28 oC. In the optimal culture medium, the maximum EPS production was 11.967 g L–1 in shake flask. Two groups of EPSs (designated as Fr-I and Fr-II) were obtained from the culture filtrates by size exclusion chromatography
(SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The weight-average molar masses of Fr-I and Fr-II of EPS were determined to be 6.327104 and 1.478104 g mol–1, respectively. The SEC/MALLS analysis revealed that the molecular
formation of Fr-I is of nearly globular shape. Furthermore, the experiments in vitro indicated that X. nigripes EPS exhibited high antioxidative effects though its antitumour activity was limited.
Keywords
Optimization; exopolysaccharides; Xylaria nigripes; molecular characterization; antioxidant; antitumour
Hrčak ID:
104797
URI
Publication date:
1.7.2013.
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