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Zou P.,Harbin Institute of Technology | Yang X.,Harbin Institute of Technology | Yang X.,Chinese Academy of Agricultural Sciences | Huang W.-W.,Harbin Institute of Technology | And 7 more authors.
Molecules | Year: 2013

Pinus koraiensis polysaccharides (PKP) were extracted by hot water from P. koraiensis pine cones. Five polysaccharide fractions named PKP-A, PKP-B, PKP-C, PKP-D and PKP-E were successfully separated at final ethanol concentrations of 30%, 50%, 60%, 70% and 80%, respectively. HPLC, FT-IR, GC-MS and automatic amino-acid analysis were applied to investigate their chemical characteristics. Monosaccharide component analysis indicated that the five fractions were all composed of D-ribose, L-rhamnose, L-arabinose, D-xylose, D-mannose, D-glucose and D-galactose, but their molar ratios were quite different. HPLC results revealed that the polysaccharides precipitated by higher concentrations of ethanol solution had lower molecular masses. Moreover, the antioxidant activities of the five fractions were studied on the basis of hydroxyl radical and ABTS radical scavenging tests. The five graded polysaccharide fractions exhibited good inhibitory power, and MTT tests in vitro showed the IC 50 of PKP-A and PKP-E were 1,072.5 and 2,070.0 μg·mL -1, respectively. These results demonstrated that the PKP could be a potential source of natural antioxidants or dietary supplements. © 2013 by the authors; licensee MDPI, Basel, Switzerland. Source

Xu R.-B.,Harbin Institute of Technology | Yang X.,Harbin Institute of Technology | Yang X.,Chinese Academy of Agricultural Sciences | Wang J.,Chinese Academy of Agricultural Sciences | And 10 more authors.
International Journal of Molecular Sciences | Year: 2012

The traditional method of gas chromatography-mass spectrometry for monosaccharide component analysis with pretreatment of acetylation is described with slight modifications and verified in detail in this paper. It was then successfully applied to the quantitative analysis of component monosaccharides in polysaccharides extracted from the pine cones. The results demonstrated that the three pine cone polysaccharides all consisted of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose in different molar ratios. According to the recovery experiment, the described method was proved accurate and practical for the analysis of pine cone polysaccharides, meeting the need in the field of chemical analysis of Pinus plants. Furthermore; the chemical characteristics, such as neutral sugar, uronic acids, amino acids, molecular weights, and antioxidant activities of the polysaccharides were investigated by chemical and instrumental methods. The results showed that the chemical compositions of the polysaccharides differed from each other, especially in the content of neutral sugar and uronic acid. In the antioxidant assays, the polysaccharide fractions exhibited effective scavenging activities on ABTS radical and hydroxyl radical, with their antioxidant capabilities decreasing in the order of PKP > PAP > PSP. Therefore, although the polysaccharide fractions had little effect on superoxide radical scavenging, they still have potential to be developed as natural antioxidant agents in functional foods or medicine. © 2012 by the authors; licensee MDPI, Basel, Switzerland. Source

Wang J.,Beijing Institute of Technology | Wang J.,Key Laboratory of Agrifood Safety and Quality | Wang J.,Hebei North University | Liu Y.,Hebei North University | Lan F.,Hebei North University
Lecture Notes in Electrical Engineering | Year: 2014

Saccharifying naked oat juice was chosen for fermentation by instant active dry yeast, lactic acid bacteria, and wine active dry yeast to produce fermentation beverage. Effects of the strains, inoculum size, fermentation time, and the addition of xylitol and pectin on physical and chemical indexes and sensory evaluation of the beverage were studied. On the basis of single factor test, orthogonal experiment of L9 (34) was used to optimize the technical parameters. The results indicated that the optimal process conditions were: 4 % wine yeast, 20 h, 7 % xylitol, and 0.45 % pectin. Under these conditions, the obtained beverage was perfectly clear and cream-colored, with its well-distributed constitution and rich naked oat flavor. Its sensory score reached up to 95.2 and its precipitation rate 13.5 %. This study aims to provide the theory basis for the development of highly processed products of naked oat. © Springer-Verlag Berlin Heidelberg 2014. Source

Wang P.,Key Laboratory of Agrifood Safety and Quality | Wang P.,Beijing Institute of Technology | Wang R.,Key Laboratory of Agrifood Safety and Quality | Wang R.,Beijing Institute of Technology | And 5 more authors.
Biosensors and Bioelectronics | Year: 2016

A novel and ultra sensitive immunochromatographic assay sensor (ICA) based on up conversion phosphor (UCP) for quantitative detection of clenbuterol (CL) was developed. Monoclonal antibody against CL was labeled with UCP beads. The detection strategy is based on competitive immunoreaction between CL antibodies conjugated to UCP beads and CL or CL antigen on the UCP-ICA sensor. It enables ultra sensitive detection of CL in one single test without complicated sample preparation. Sensing results can be obtained within 10. min. Under optimized conditions, visual limit of detection (vLOD) of UCP-ICA for CL was 0.1 ng/mL. Calculated LOD (cLOD) for CL, as low as 0.01 ng/mL, could be achieved with the UCP-ICA sensor. Recoveries of CL in various sample matrixes ranged from 73.0% to 92.2% and relative standard deviations (RSD) were below 12%. The assay was evaluated with spiked and real samples and the results were compared with liquid chromatography-tandem mass. The developed novel assay method based on UCP could be a potential alternative format for on site and rapid detection of CL as well as other illegal drugs. © 2015 Elsevier B.V. Source

Zou P.,Harbin Institute of Technology | Zou P.,Chinese Academy of Agricultural Sciences | Yang X.,Harbin Institute of Technology | Yang X.,Chinese Academy of Agricultural Sciences | And 11 more authors.
Food Chemistry | Year: 2016

Chitosan and chitosan oligosaccharides (COS) have been reported to possess various biomedical properties, including antimicrobial activities, immuno-enhancing effects, and anti-tumour activities. COS have attracted considerable interest due to their physicochemical properties, and potential applications in the food and pharmaceutical industries, especially in cancer therapies. This paper describes the preparation of COS and their physicochemical properties, and modification, which aids understanding of their biological activities. Based on the latest reports, several biological and anti-tumour activities of COS will be discussed. The proposed anti-tumour mechanisms of COS are summarised, to provide comprehensive insights into research on the molecular level. Finally, the potential applications and future development of the biopolymer will be discussed. ©2015 Elsevier Ltd. All rights reserved. Source

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