title: Effects of Cymbopogon citratus Stapf water extract on rat antioxidant defense system.
abstract: BACKGROUND
  Cymbopogon citratus, Stapf(CCS) is commonly known as lemon grass. Previous studies showed that it has a strong antioxidant property and have been traditionally used as analgesic, antipyretic, antiseptic in SoutheastAsia. However, the effect of CCS on antioxidant defense system has not been demonstrated.
  
  
  OBJECTIVE
  The present study was conducted to investigate the effects of CCS water extract on rat antioxidant defense system, especially on the expression of y-glutamylcysteine ligase (γ-GCL) and heme oxygenase-1 (HO-1).
  
  
  METHODS
  The CCS water extract was screenedfor its phytochemical contents and antioxidant activity in vitro. Moreover, the extract was studied in rats to evaluate its effects in vivo. Male Sprague-Dawley rats aged eight weeks (250±20 g) were orally administered with CCS at 250, 500 and 1,000 mg/kg/day for one month.
  
  
  RESULTS
  The extract contained flavonoids (496.17 mg gallic acid/g CCS extract) and phenolic compounds (4,020.18 mg catechin/g CCS extract). The scavenging activity (DPPH assay) of the extract was demonstrated by EC50 of 917.76±86.89 μg/ ml whereas the EC50 of the potent antioxidant, vitamin C was 31.22±1.84 μg/ml. In the animals, the protein expression of antioxidant enzymes, γGCL and HO-1 was significantly increased in the high dose-treated animals (1,000 mg/kg/day). This was consistent with elevation ofserum total antioxidant capacity.
  
  
  CONCLUSIONS
  Taken together the present study provides evidence that CCS water extract exhibits antioxidant activity and antioxidant enzymes induction in vivo.
authors.forename: Nuntiya
authors.initials: N
authors.lastname: Somparn
authors.forename: Suphaket
authors.initials: S
authors.lastname: Saenthaweesuk
authors.forename: Jarinyaporn
authors.initials: J
authors.lastname: Naowaboot
authors.forename: Atcharaporn
authors.initials: A
authors.lastname: Thaeomor
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D031743:Cymbopogon; D005419:Flavonoids / Q000494:pharmacology; D005721:Glutamate-Cysteine Ligase / Q000187:drug effects* / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D010636:Phenols / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D051547:Heme Oxygenase-1; D005721:Glutamate-Cysteine Ligase; D001205:Ascorbic Acid