title: Biological activities of flavonoid-rich fraction of Eryngium caucasicum Trautv.
abstract: OBJECTIVE
  Eryngium (E.) caucasicum was found as a new cultivated vegetable plant in northern Iran and used in several local foods. Little information is available on biological properties of E. caucasicum. In this work antioxidant activity of flavonoid-rich fraction of this plant was investigated by eight in vitro assay systems.
  
  
  METHODS
  1,1-diphenyl-2-picryl hydrazyl radical (DPPH), nitric oxide and hydrogen peroxide scavenging activities, Fe2+ chelating ability, reducing power and hemoglobin-induced linoleic acid peroxidation were used to evaluate antioxidant activities. Antihemolytic activities were evaluated against CuOOH and H2O2 induced hemolysis in rat erythrocyte.
  
  
  RESULTS
  IC50 for DPPH scavenging activity was 391.2 +/- 14.9, 706.6 +/- 22.3 and 779.7 +/- 16.7 microg ml(-1) for aqueous (AQ), ethyl acetate (EA) and n-hexane (HE) fractions, respectively. There was no difference between reducing power of AQ fraction activity and vitamin C (p > 0.05). IC50 for NO radical-scavenging activity was in order of AQ (133.5 +/- 6.2 microg ml(-1)) > EA (350.1 +/- 14.8 microg ml(-1)) > and HE (639.9 +/- 21.7 microg ml(-1)) fractions, respectively. Extracts showed weak Fe2+ chelating ability. HE fraction showed better activity (173.5 +/- 9.6 microg ml(-1)). Extracts exhibited weak hydrogen peroxide scavenging activity but exhibited very good antioxidant activity against the hemoglobin-induced linoleic acid peroxidation. There was no significant difference between AQ fraction and vitamin C (p > 0.01). Fractions delayed the onset of the CuOOH induced hemolysis. AQ fraction showed very high total phenol and flavonoid contents which was higher than other fractions. High phenol and flavonoid content of AQ fraction may lead to its better antioxidant activity.
  
  
  CONCLUSIONS
  E. caucasicum fractions exhibited different levels of antioxidant and antihemolytic activities in all tested models. These results can be useful as a starting point of view for further applications of E. caucasicum aerial parts or its constituents in pharmaceutical preparations.
authors.affiliation: Applied Biotechnology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran. Nabavisf@gmail.com
authors.forename: S M
authors.initials: SM
authors.lastname: Nabavi
authors.forename: S F
authors.initials: SF
authors.lastname: Nabavi
authors.forename: H
authors.initials: H
authors.lastname: Alinezhad
authors.forename: M
authors.initials: M
authors.lastname: Zare
authors.forename: R
authors.initials: R
authors.lastname: Azimi
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D031049:Eryngium / Q000737:chemistry*; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D005419:Flavonoids / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D006461:Hemolysis / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D020128:Inhibitory Concentration 50; D008297:Male; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012997:Solvents / Q000737:chemistry
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D012997:Solvents; D006861:Hydrogen Peroxide; D001205:Ascorbic Acid