왕거머리말의 생리활성 성분의 분리

Abstract

As the human lifespan has been extended due to great advances in medical science, the incidence of various adult diseases has rapidly increased - cancer, cardiac disorder, diabetes, dementia etc. In recent years, there has been growing interest in the use of natural products, especially those derived from terrestrial plants or seaweeds. Plant-based medicine has definitely played an expanding role in the treatment of adult diseases.

As a part of our search for bioactive compounds from marine organisms, we collected Zostera asiatica, one of the marine flowering plants, from the southern coastal area of Korea. Dried samples were extracted twice: with acetone/methylene chloride (A+M) and with methanol (MeOH), respectively. The combined crude extracts were evaporated in vacuo, and then the residue was partitioned between water and methylene chloride. The aqueous layer was fractionated into H2O and n-butanol, and then the organic layer was also fractionated into 85% aq. MeOH and n-hexane, successively.

The crude extracts and their solvent fractions were evaluated for antioxidant, antiproliferative, and antiinflammatory effects, respectively. In antioxidant bioassay, n-BuOH and 85% aq. MeOH fractions showed a strong scavenging effect on DPPH radical and peroxynitrites. In a cellular system using 2',7'-dichlorofluorescin diacetate (DCF-DA) as fluorescence probe in HT-1080 cells, all extracts and solvent fractions except the H2O fraction significantly decreased the level of intracellular reactive oxygen species(ROS). On the basis of the above, two flavonoids were obtained from n-BuOH fraction by bactivity-guided separation.

On the other hand, in cytotoxicity bioassay system using the MTT reduction method, the 85% aq. MeOH fraction among samples tested showed the most inhibitory effect on growth of human cancer cells AGS, HT-29, and MCF-7 cells. However, all samples didn’t exhibit the significant inhibitory effect on lipopolysaccharide(LPS)-stimulated nitric oxide(NO) production. Therefore, these results suggest that Z. asiatica may be useful as a potential candidate for both natural antioxidant to oxidative damage, and chemopreventive agent for cancer.