title: Physicochemical properties and cell-based bioactivity of Pu'erh tea polysaccharide conjugates.
abstract: Polysaccharide conjugates were prepared from Pu'erh tea and fractionated by DEAE-cellulose DE-52 column chromatography to yield one unexplored polysaccharide-conjugate fraction termed TPC-P with a molecular weight of 251,200Da. DVS (dynamic vapour sorption) result discovered that the humidity condition of long-term preservation for TPC-P is below 70% RH. Although it contained proteins, TPC-P could not bind to the Coomassie Brilliant Blue dyes G250 and R250. The "shoulder-shaped" ultroviolet absorption peak in TPC-P UV-vis scanning spectum ascribe theabrownins that inevitably adsorbed the polysaccharide conjugate. Zeta potential results demonstrated TPC-P aqueous solution merely presented the negative charge properties of polysaccharides instead of acid-base property of its protein section, and had more stability in greater than pH 5.5. No precipitation or haze occurred in the three TPC-P/EGCG aqueous mixtures during their being stored for 12h. The phase separation was observed in aqueous mixtures of TPC-P and type B gelatin. TPC-P possessed the fine stability as a function of temperature heating and cooling between 0 and 55°C. It is proposed that some properties of the covalent binding protein of TPC-P were "shielded" by its polysaccharide chains.
authors.affiliation: College of Bioengineering and Food, Hubei University of Technology, Wuhan, 430068, China. Electronic address: biomed528@163.com.
authors.forename: Xiao-Qiang
authors.initials: XQ
authors.lastname: Chen
authors.affiliation: Department of Anesthesiology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
authors.forename: Zhi-Fa
authors.initials: ZF
authors.lastname: Zhang
authors.affiliation: College of Bioengineering and Food, Hubei University of Technology, Wuhan, 430068, China.
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Gao
authors.affiliation: College of Bioengineering and Food, Hubei University of Technology, Wuhan, 430068, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Huang
authors.affiliation: College of Bioengineering and Food, Hubei University of Technology, Wuhan, 430068, China.
authors.forename: Zheng-Qi
authors.initials: ZQ
authors.lastname: Wu
mesh_terms: D002392:Catechin / Q000031:analogs & derivatives / Q000737:chemistry; D049109:Cell Proliferation / Q000187:drug effects; D055598:Chemical Phenomena; D003636:DEAE-Cellulose / Q000737:chemistry; D056945:Hep G2 Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D011134:Polysaccharides / Q000737:chemistry* / Q000494:pharmacology*; D012394:Rosaniline Dyes / Q000737:chemistry; D013227:Steam; D013662:Tea / Q000737:chemistry*; D013696:Temperature
chemical_list: D011134:Polysaccharides; D012394:Rosaniline Dyes; D013227:Steam; D013662:Tea; D002392:Catechin; D003636:DEAE-Cellulose; C045651:epigallocatechin gallate; C004692:coomassie Brilliant Blue
keywords: Physicochemical properties; Polysaccharide conjugates; Protein; Pu’erh tea