Effects of Cymbopogon citratus Stapf Water Extract on Rat Antioxidant Defense System
Nuntiya Somparn PhD*, Suphaket Saenthaweesuk MSc*, Jarinyaporn Naowaboot PhD*, Atcharaporn Thaeomor PhD**
Affiliation : * Department of Preclinical Science, Faculty of Medicine, Thammasat University, Rangsit Campus, Pathumthani, Thailand ** School of Biology, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand
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 Southeast Asia. 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 γ-glutamylcysteine ligase (γ-GCL) and heme oxygenase-1 (HO-1).
Material and Method: The CCS water extract was screened for 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, γ-GCL and HO-1 was significantly increased in the high dose-treated animals (1,000 mg/kg/day). This
was consistent with elevation of serum total antioxidant capacity.
Conclusion : Taken together, the present study provides evidence that CCS water extract exhibits antioxidant activity and
antioxidant enzymes induction in vivo.
Keywords : Cymbopogon citratus Stapf, Antioxidant, γ-glutamylcysteine ligase, Heme oxygenase-1
