Department of Oral Biochemistry and Institute of Oral Biology, College of Dentistry, Kyung Hee University
In the present study, total methanol extracts prepared from
Alpinia katsumadai showed significant protective effects
against the oxidative stress induced by hydrogen peroxide,
UV-C or γ-ray irradiation. These protective effects were
substantially increased by treatment with 20~100 μg/ml of
the extract. The A. katsumadai total methanol preparation
was further fractionated into n-hexane, dichloromethane,
ethylacetate, n-butanol and water fractions. Among these
five fractions, the ethylacetate and butanol fractions of A.
katsumadai showed the strongest protective effects against
oxidative stress induced by UV-C and γ-ray irradiation.
These fractions also showed high DPPH radical scavenging
and lipid peroxidation inhibitory activities. In addition, both
fractions displayed cell proliferation activation effects, as
evidenced by significant increases in colony formation. Our
current data thus suggest that the mechanisms underlying
the protective effects of A. katsumadai against oxidative
damage may include radical scavenging, protection against
cell membrane damage and stimulation of cell proliferation.