http://dx.doi.org/10.4314/tjpr.v12i5.7
Abstract
Purpose:
To evaluate the mechanism of
antioxidant activity of the methanol extract of
Codonopsis pilosula.
Methods: Anti-oxidative
properties were assessed by measuring free radical
scavenging activity, nitric oxide (NO) levels, protein
oxidation and reducing power, while the mechanism of
antioxidative effect of Codonopsis pilosula extract was
determined by measuring iNOS and COX-2 expression in
lipopolysaccharide (LPS)-stimulated raw cells.
Results:
Codonopsis pilosula extract (CPE)
exerted significant DPPH free radical and NO-scavenging
activities. Protein oxidation was decreased by 30 % by
the CPE (1mg/ml). The extract (1mg/ml) enhanced reducing
power 16-fold (compared with control). LPS-induced
production of iNOS was significantly inhibited by the
extract (60 %), suggesting that it inhibits NO
production by suppressing iNOS expression. However,
LPS-induced production of COX-2 was not significantly (p
< 0.05) inhibited by the extract. The levels of total
phenolics, total flavonoids, and total anthocyanin in
CPE were 0.38, 2.10, and 2.47 mg/g, respectively.
Conclusion: These results
suggest that CPE exerts marked antioxidant activity via
inhibition of iNOS and protein oxidation.
Keywords: Codonopsis
pilosula, Lipopolysaccharide, Cyclooxygenase-2 (COX-2),
Free radicals, Inducible nitric oxide synthase (iNOS),
Nitric oxide (NO)
