title: Hydrolyzable tannins from the fruits of Terminalia chebula Retz and their α-glucosidase inhibitory activities.
abstract: Nine hydrolyzable tannins, including three previously unknown and six artifacts, were isolated, together with thirty-nine known ones, from the fruits of Terminalia chebula Retz. (Combretaceae). They were identified as 1,2,3-tri-O-galloyl-6-O-cinnamoyl-β-d-glucose, 1,2,3,6-tetra-O-galloyl-4-O-cinnamoyl-β-d-glucose, 4-O-(2″,4″-di-O-galloyl-α-l-rhamnosyl)ellagic acid, 1'-O-methyl neochebulanin, dimethyl neochebulinate, 6'-O-methyl neochebulagate, dimethyl neochebulagate, dimethyl 4'-epi-neochebulagate, and methyl chebulagate by the spectroscopic interpretation. After evaluation for α-glucosidase inhibition of all isolated compounds, 1,2,3,6-tetra-O-galloyl-4-O-cinnamoyl-β-d-glucose and 4-O-(2″,4″-di-O-galloyl-α-l-rhamnosyl)ellagic acid showed significant inhibitory activities with IC50values of 2.9 and 6.4 μM, respectively. In addition, inhibition kinetic studies showed that both compounds have mixed-type inhibitory activities with the inhibition constants (Ki) of 1.9 and 4.0 μM, respectively.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Republic of Korea.
authors.forename: Dong Young
authors.initials: DY
authors.lastname: Lee
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Republic of Korea.
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Kim
authors.affiliation: College of Pharmacy, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: Heejung
authors.initials: H
authors.lastname: Yang
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 151-742, Republic of Korea. Electronic address: shsung@snu.ac.kr.
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Sung
mesh_terms: D005638:Fruit / Q000737:chemistry*; D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D047348:Hydrolyzable Tannins / Q000737:chemistry* / Q000302:isolation & purification; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry; D029766:Terminalia / Q000737:chemistry*; D000520:alpha-Glucosidases / Q000378:metabolism
chemical_list: D065089:Glycoside Hydrolase Inhibitors; D047348:Hydrolyzable Tannins; D010936:Plant Extracts; D000520:alpha-Glucosidases
keywords: Combretaceae α-glucosidase; Hydrolyzable tannin; IC(50) value; Terminalia chebula