title: In vitro studies to assess the antioxidative, radical scavenging and arginase inhibitory potentials of extracts from Artocarpus altilis, Ficus exasperate and Kigelia africana.
abstract: OBJECTIVE
  To justify the use of Artocarpus altilis (A. altilis), Ficus exasperata (F. exasperata) and Kigelia africana (K. africana) in ethnomedicine for the treatment of several ailments and to evaluate the in vitro antioxidant, radical scavenging and arginase inhibitory potentials of these herbs and compared with catechin (Standard).
  
  
  METHODS
  Antioxidant activities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide, hydrogen peroxide (H2O2) and hydroxyl (OH) radicals scavenging methods. The flavonoids and phenolics content, inhibition of arginase activity, Fe(2+)/ascorbate-induced lipid peroxidation (LPO) and reducing power were also determined.
  
  
  RESULTS
  The A. altilis, F. exasperata and K. africana showed dose-dependent and significant scavenging of DPPH, H2O2 and OH radicals in vitro relative to catechin. The A. altilis and F. exasperata effectively scavenged DPPH radical with IC50 of 593 and 635 µg/mL and, OH radical with IC50 of 487 and 514 µg/mL, respectively. The DPPH and OH radicals scavenging activities followed the order A. altilis>F. exasperata>K. africana. In addition, A. altilis and F. exasperata significantly (P<0.05) inhibited LPO in a dose-dependent manner. The A. altilis extract had the most potent inhibitory activity against LPO with 79% relative to catechin (28%) at 750 µg/mL. The reducing power followed the order: A. altilis>Catechin>F. exasperata>K. africana at 1 000 µg/mL. The A. altilis at 500 and 750 µg/mL significantly (P<0.05) inhibited arginase activity by 63% and 67%, respectively. The flavonoids contents were found to be highest in A. altilis.
  
  
  CONCLUSIONS
  Extracts of A. altilis and F. exasperata are potent antioxidative agents with strong radical scavenging activity and inhibition of lipid peroxidation.
authors.affiliation: Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: Olubukola Oyebimpe
authors.initials: OO
authors.lastname: Akanni
authors.affiliation: Cancer Research and Molecular Biology Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: Solomon Eduviere
authors.initials: SE
authors.lastname: Owumi
authors.affiliation: Drug Metabolism and Toxicology Research Laboratories, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria.
authors.forename: Oluwatosin Adekunle
authors.initials: OA
authors.lastname: Adaramoye
keywords: Antioxidant; Arginase; Free radicals; lipid peroxidation