Abstract
Ostericum koreanum maximowicz (Umbelliferae), a medicinal herb in Korean Oriental Medicine, has been applied to treat cold, headache, neuralgia and arthralgia. The ethyl acetate fraction of O. koreanum root was subjected to in vitro antioxidant activity with different methods for free radical scavenging activities. In addition, the cell viability and nitric oxide release assays were performed here for the first time in neuroblastoma (Neuro-2a) cell cultures. Among all the tested methods, the ethyl acetate fraction was expressed very active, exhibiting a good Trolox equivalent values and IC50, comparable to that of the commercial antioxidants, Trolox and ascorbic acid, respectively. The results showed that there was a reduction of cell viability by the fraction in a concentration dependent manner. These results suggest that O. koreanum shows good antioxidant activities in vitro by inhibiting free radicals. These findings provide a rationale for the in vivo testing. Also, the major constituents behind the antioxidant mechanisms of this fraction warrant further study.