title: Structure elucidation and anti-tumor activities of water-soluble oligosaccharides from Lactarius deliciosus (L. ex Fr.) Gray.
abstract: BACKGROUND
  Oligosaccharides are composed of a variable number of monosaccharide units and very important in the biologically diverse of biological systems.
  
  
  METHODS
  Crude water-soluble oligosaccharide was extracted from the fruiting bodies with water and then successively purified by DEAE-cellulose 52 and Sephadex G-100 column chromatography, yielding one major oligosaccharides fractions: LES-A. Structural features of Lactarius deliciosus (L. ex Fr.) Gray oligosaccharide (LDGO-A) were investigated by a combination of monosaccharide component analysis by thin layer chromatography, infrared spectra, nuclear magnetic resonance spectroscopy, scanning electron microscopy, and high-performance gel permeation chromatography analysis.
  
  
  RESULTS
  The results indicated that LDGO-A was composed of D-glucose and D-xylose, and the average molecular sizes was approximately 945 Da. The anti-tumor activity of LDGO-A was evaluated in vivo. The inhibitory rate in mice treated with 40 mg/kg LDGO-A can reach 40.02%, being the highest in the three doses, which may be comparable to mannatide. Histology of immune organs shows that the tissues arranged more regular and firmer, but the tumor tissue arranged looser in LDGO-A group than those in the control group. Meanwhile, there is no obvious damage to other organs, such as heart. The anti-tumor activity of the LDGO-A was usually believed to be a consequence of the stimulation of the cell-mediated immune response because it can significantly promote the lymphocyte and macrophage cells in the dose range of 100-400 μg/mL in vitro. LDGO-A also effected the expression of some housekeeping genes mRNA in S180 tumor.
  
  
  CONCLUSIONS
  Accordingly, the LDGO-A might serve as an effective healthcare food and source of natural anti-tumor compounds.
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Sciences, China West Normal University, Nanchong, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Ding
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Sciences, China West Normal University, Nanchong, China.
authors.forename: Yiling
authors.initials: Y
authors.lastname: Hou
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Sciences, China West Normal University, Nanchong, China.
authors.forename: Wanru
authors.initials: W
authors.lastname: Hou
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Sciences, China West Normal University, Nanchong, China.
authors.forename: Yuanxiu
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Sciences, China West Normal University, Nanchong, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Fu
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Sciences, China West Normal University, Nanchong, China.
authors.forename: Hongqing
authors.initials: H
authors.lastname: Zhu
keywords: Anti-tumor assay; Lactarius deliciosus (L. ex Fr.) Gray; oligosaccharide; structure elucidation; water-soluble