title: Free radical scavenging activities and inhibition of inflammatory enzymes of phenolics isolated from Tripodanthus acutifolius.
abstract: BACKGROUND
  Leaf extracts from Tripodanthus acutifolius (Ruiz and Pavón) Van Tieghem have long been used in Argentinean traditional medicine as anti-inflammatory, however, there is no scientific evidence which supports this use in the literature.
  
  
  OBJECTIVE
  The present study was conducted to evaluate the ability of five phenolic compounds purified from infusion prepared from Tripodanthus acutifolius leaves to inhibit key enzymes in inflammatory processes. As anti-inflammatory compounds frequently possess free radical scavenging activities, purified substances were comparatively evaluated to asses their free radical scavenging properties. Genotoxic effects were also evaluated.
  
  
  METHODS
  Compounds were evaluated on their ability to inhibit hyaluronidase and cyclooxygenase-2 (COX-2) activities to assess their anti-inflammatory capacities. Free radical scavenging activity was assessed by: 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH), superoxide anion assay and the inhibition on lipid peroxidation. Genotoxicity was evaluated by Bacillus subtilis rec assay.
  
  
  RESULTS
  Fractionation of Tripodanthus acutifolius infusion yielded a novel phenylbutanoid derivative (tripodantoside) and four known flavonoid glycosides (rutin, nicotiflorin, hyperoside and isoquercitrin). Flavonoids produced higher inhibition on hyluronidase activity (IC(50) approximately 1.7 mM) than tripodantoside (IC(50)=27.90 mM). A similar COX-2 inhibition activity was exerted by tripodantoside and monoglycosilated flavonoids (IC(50) approximately 50 microM). Compounds were strong radical scavengers, with effective concentration 50 (EC(50)) values for DPPH in the range of 2.7-6.3 microg/mL, and for superoxide anion in the range of 3.9-8.7 microg/mL. All compounds scavenged peroxyl radicals in the lipid peroxidation assay. The substances showed no genotoxic effects.
  
  
  CONCLUSIONS
  The anti-inflammatory effects, free radical scavenging activities and lack of genotoxicity of purified compounds may support the folk use of infusion from Tripodanthus acutifolius leaves as anti-inflammatory.
authors.affiliation: Instituto de Estudios Vegetales Dr. A.R. Sampietro, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Miguel de Tucumán, Tucumán, Argentina.
authors.forename: José R
authors.initials: JR
authors.lastname: Soberón
authors.forename: Melina A
authors.initials: MA
authors.lastname: Sgariglia
authors.forename: Diego A
authors.initials: DA
authors.lastname: Sampietro
authors.forename: Emma N
authors.initials: EN
authors.lastname: Quiroga
authors.forename: Marta A
authors.initials: MA
authors.lastname: Vattuone
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics; D001713:Biphenyl Compounds / Q000737:chemistry; D002417:Cattle; D051546:Cyclooxygenase 2 / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D006801:Humans; D006821:Hyaluronoglucosaminidase / Q000037:antagonists & inhibitors / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D028183:Loranthaceae; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D010851:Picrates / Q000737:chemistry; D018515:Plant Leaves; D011794:Quercetin / Q000031:analogs & derivatives / Q000494:pharmacology; D011994:Recombinant Proteins / Q000378:metabolism; D012431:Rutin / Q000494:pharmacology
chemical_list: D000893:Anti-Inflammatory Agents; D001713:Biphenyl Compounds; D052246:Cyclooxygenase 2 Inhibitors; D005419:Flavonoids; D016166:Free Radical Scavengers; D010636:Phenols; D010851:Picrates; D011994:Recombinant Proteins; C513882:nicotiflorin; C016527:isoquercitrin; D012431:Rutin; C021304:hyperoside; D011794:Quercetin; C004931:1,1-diphenyl-2-picrylhydrazyl; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D006821:Hyaluronoglucosaminidase