title: Physicochemical characteristics of polysaccharide conjugates prepared from fresh tea leaves and their improving impaired glucose tolerance.
abstract: Hot-water extracts were prepared from fresh tea leaves and fractionated by DEAE-cellulose DE-52 column chromatography to yield one unexplored polysaccharide-conjugate fraction TPC-L (tea polysaccharide conjugates). Chemical components, molecular weight and its distribution, water vapor sorption properties, zeta potentials and optical characteristics of TPC-L were investigated. As compared with injured cell group, the two dosages of TPC-L (150 and 300 μg/mL) were discovered to possess remarkably protective effect on human umbilical vein endothelial cells against impairments induced by high glucose in a dose-dependent manner (p < 0.05, p < 0.001, respectively). Compared with group NC (normal control), the ingestion of 40 mg/kg of TPC-L could significantly reduce blood glucose levels of normal mice ingesting starch, and significant difference of AUC (area under the curve of blood glucose) and ΔAUC (p < 0.05, p < 0.01) at the postprandial time point of 0.5 and 1.0 h were observed. The three dosages of TPC-L (10, 40 and 160 mg/kg) did not significantly lower postprandial blood glucose levels of normal mice ingesting glucose. TPC-L could improve starch tolerance to prevent impaired glucose tolerance (IGT) from developing into diabetes as well as protective effects on HUVE cells against impairments induced by high glucose It was suggested that TPC-L improved IGT through its capability of inhibition on digestive enzymes.
authors.affiliation: Hubei Collaborative Innovation Center for Industrial Fermentation, Glyn O. Phillips Hydrocolloid Research Centre at HUT, Hubei University of Technology, Wuhan 430068, China; College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310035, China. Electronic address: biomed528@163.com.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Chen
authors.affiliation: Hubei Collaborative Innovation Center for Industrial Fermentation, Glyn O. Phillips Hydrocolloid Research Centre at HUT, Hubei University of Technology, Wuhan 430068, China.
authors.forename: Yapeng
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Hubei Collaborative Innovation Center for Industrial Fermentation, Glyn O. Phillips Hydrocolloid Research Centre at HUT, Hubei University of Technology, Wuhan 430068, China.
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Nishinari
authors.affiliation: Xinhua Hospital of Hubei Province, Wuhan 430015, China.
authors.forename: Heng
authors.initials: H
authors.lastname: We
authors.affiliation: Hangzhou Hospital of Traditional Chinese Medicine, Hangzhou 310007, China.
authors.forename: Chaochao
authors.initials: C
authors.lastname: Sun
authors.affiliation: Bohai University, Jinzhou 121013, China. Electronic address: lijr6491@163.com.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Li
authors.affiliation: Tea Research Institute, China Academy of Agricultural Sciences, Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, China, Key Laboratory of Tea Processing Engineering of Zhejiang Province, Hangzhou 310008, China. Electronic address: jywtea@163.com.
authors.forename: Yongwen
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D028241:Camellia sinensis / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D005951:Glucose Tolerance Test; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects; D006801:Humans; D008297:Male; D008813:Mice, Inbred ICR; D008970:Molecular Weight; D009005:Monosaccharides / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry* / Q000494:pharmacology*; D019518:Postprandial Period; D013055:Spectrophotometry, Infrared; D013213:Starch / Q000494:pharmacology; D013662:Tea / Q000737:chemistry
chemical_list: D001786:Blood Glucose; D009005:Monosaccharides; D011134:Polysaccharides; D013662:Tea; D013213:Starch; D005947:Glucose
keywords: Endothelial cells; Impaired glucose tolerance; Tea polysaccharides conjugates