title: Ixorapeptide I and ixorapeptide II, bioactive peptides isolated from Ixora coccinea.
abstract: Two novel derivatized peptides, designated as ixorapeptide I (1) and ixorapeptide II (2), in addition to 28 other known compounds, were isolated from the MeOH extract of Ixora coccinea using bioassay-guided fractionation. The structures of metabolites 1 and 2 were determined by interpretation of the spectroscopic data and Marfey's method. Compound 1 exhibited selective potency against Hep3B liver cancer cell line with an IC(50) value of 3.36 μg/mL, and compound 2 did not show notable cytotoxicity toward cancer cell lines but could inhibit superoxide anion generation and elastase release with IC(50) values of 0.21 and 0.27 μg/mL, respectively. Moreover, kaempferol and luteolin from this plant showed inhibition with IC(50) values of 3.55 and 2.56 μg/mL, respectively on platelet aggregation induced by collagen.
authors.affiliation: Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chia-Lin
authors.initials: CL
authors.lastname: Lee
authors.forename: Yung-Chih
authors.initials: YC
authors.lastname: Liao
authors.forename: Tsong-Long
authors.initials: TL
authors.lastname: Hwang
authors.forename: Chin-Chung
authors.initials: CC
authors.lastname: Wu
authors.forename: Fang-Rong
authors.initials: FR
authors.lastname: Chang
authors.forename: Yang-Chang
authors.initials: YC
authors.lastname: Wu
mesh_terms: D045744:Cell Line, Tumor; D006801:Humans; D044949:Kaempferols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D047311:Luteolin / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010196:Pancreatic Elastase / Q000378:metabolism; D010455:Peptides / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D019666:Rubiaceae / Q000737:chemistry / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013481:Superoxides / Q000378:metabolism
chemical_list: D044949:Kaempferols; D010455:Peptides; D010975:Platelet Aggregation Inhibitors; C556337:ixorapeptide I; C556338:ixorapeptide II; D013481:Superoxides; C006552:kaempferol; D010196:Pancreatic Elastase; D047311:Luteolin