title: Chemical compositions and bioactivities of crude polysaccharides from tea leaves beyond their useful date.
abstract: The chemical compositions and bioactivities of crude tea polysaccharides (TPS) from the out-of-date tea leaves (beyond their useful date), namely Xihu Longjing (XTPS), Anxi Tieguanyin (TTPS), Chawentianxia (CTPS) and Huizhoulvcha (HTPS), in market were investigated. These TPS showed similar neutral sugar content and different distribution of molecular weight (1-800 kD). These crude TPS were mainly composed of rhamnose, arabinose, galactose, glucose, xylose, mannose, and galacturonic acid. IR spectra confirmed that these crude TPS were composed of polysaccharide, protein and uronic acids. These TPS showed similar DPPH scavenging activity and exhibited lower DPPH scavenging activities than Vc within 25-200 μg/mL. However, these TPS with higher concentrations (200-400 μg/mL) showed similar DPPH scavenging activity with Vc. HTPS exhibited significant higher superoxide anion scavenging activity than others TPS and gallic acid. XTPS showed significant higher inhibitory effects on α-glucosidase and α-amylase with inhibitory percentages of 64.35% and 82.24% than others TPS. TTPS, XTPS, and HTPS exhibited similar inhibition ability on α-d-glucosidase and α-amylase. The overdue tea leaves can be a resource of tea polysaccharides as function food.
authors.affiliation: Institute of Food Engineering, Shanghai Normal University, 100 Guilin Rd, Shanghai 200234, PR China. jianboxiao@yahoo.com
authors.forename: Jianbo
authors.initials: J
authors.lastname: Xiao
authors.forename: Jianglei
authors.initials: J
authors.lastname: Huo
authors.forename: Huixian
authors.initials: H
authors.lastname: Jiang
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000032:analysis / Q000737:chemistry* / Q000494:pharmacology; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors / Q000378:metabolism; D028241:Camellia sinensis / Q000737:chemistry*; D002681:China; D005504:Food Analysis; D005519:Food Preservation; D065089:Glycoside Hydrolase Inhibitors; D006603:Hexuronic Acids / Q000032:analysis / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009005:Monosaccharides / Q000032:analysis / Q000378:metabolism; D010851:Picrates / Q000037:antagonists & inhibitors / Q000378:metabolism; D010936:Plant Extracts / Q000032:analysis / Q000737:chemistry* / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D011134:Polysaccharides / Q000032:analysis / Q000737:chemistry* / Q000494:pharmacology; D051381:Rats; D013662:Tea / Q000737:chemistry*; D014020:Tissue Extracts; D014574:Uronic Acids / Q000032:analysis / Q000378:metabolism; D000516:alpha-Amylases / Q000037:antagonists & inhibitors / Q000378:metabolism; D000520:alpha-Glucosidases / Q000378:metabolism
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D065089:Glycoside Hydrolase Inhibitors; D006603:Hexuronic Acids; D009005:Monosaccharides; D010851:Picrates; D010936:Plant Extracts; D011134:Polysaccharides; D013662:Tea; D014020:Tissue Extracts; D014574:Uronic Acids; C007819:galacturonic acid; C004931:1,1-diphenyl-2-picrylhydrazyl; D000516:alpha-Amylases; D000520:alpha-Glucosidases