title: Free radical scavenging and antielastase activities of flavonoids from the fruits of Thuja orientalis.
abstract: Bioassay-guided fractionation of the MeOH extract of Thuja orientalis fruits using a DPPH (2,2-diphenyl-1-picrylhydrazyl) assay led to the isolation of 9 flavonoids: cupressuflavone (1), amentoflavone (2), robustaflavone (3), afzelin (4), (+)-catechin (5), quercitrin (6), hypolaetin 7-O-beta-xylopyranoside (7), isoquercitrin (8) and myricitrin (9). Their chemical structures were determined by spectroscopic analyses. The free radical scavenging and human neutrophil elastase (HNE) inhibitory activities were evaluated for the isolated compounds. By DPPH scavenging assay, compounds 5, 6, 7, 8 and 9 showed anti-oxidant activities with IC(50) values of 28.66, 31.19, 18.30, 26.63 and 15.10 microM, respectively. By ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] scavenging assay, these compounds also exhibited potent anti-oxidant activities with IC(50) values of 6.77, 13.96, 6.97, 22.79 and 9.96 microM, respectively. Of note, compounds 1, 2 and 3 showed significant HNE inhibitory activities with IC(50) values of 8.09, 1.27 and 1.33 microM, respectively.
authors.affiliation: Functional Metabolite Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea.
authors.forename: Guang-Hua
authors.initials: GH
authors.lastname: Xu
authors.forename: In-Ja
authors.initials: IJ
authors.lastname: Ryoo
authors.forename: Young-Hee
authors.initials: YH
authors.lastname: Kim
authors.forename: Soo-Jin
authors.initials: SJ
authors.lastname: Choo
authors.forename: Ick-Dong
authors.initials: ID
authors.lastname: Yoo
mesh_terms: D052160:Benzothiazoles; D001713:Biphenyl Compounds / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005638:Fruit / Q000737:chemistry; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D009504:Neutrophils / Q000201:enzymology; D010084:Oxidation-Reduction; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors*; D010851:Picrates / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry; D029783:Thuja / Q000737:chemistry*
chemical_list: D052160:Benzothiazoles; D001713:Biphenyl Compounds; D004791:Enzyme Inhibitors; D005419:Flavonoids; D016166:Free Radical Scavengers; D010851:Picrates; D013451:Sulfonic Acids; D013844:Thiazoles; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; C004931:1,1-diphenyl-2-picrylhydrazyl; D010196:Pancreatic Elastase