해면동물 Hyrtios erectus로부터 생리활성 성분의 탐색

Abstract

Specimens of the sponge Hyrtios erectus were consecutively extracted with methylene chloride and methanol, respectively. Combined crude extracts were fractionated into n-hexane, 85% aq.MeOH, n-BuOH and water fractions according to solvent polarity.

The crude extract and its solvent fractions were assessed for their scavenging effect on DPPH radical and peroxynitrite in a non-cellular system. There was no significant scavenging activity with any DPPH samples including crude extracts. However, for peroxynitrite, all tested samples showed a dose-dependent scavenging effect. Among them, n-hexane and 85% aq.MeOH fractions showed the most potent activity, comparable with vitamin C and penicillamine. Scavenging effect on intracellular ROS in HT- 1080 cells as well as reducing antioxidant power on ferric ion were also measured for crude extract and its four solvent fractions. All tested samples revealed the strong scavenging and reducing effect on both ROS and ferric ions, respectively, in a dose-dependent manner. In addition, all samples significantly inhibited production of LPS-activated nitric oxide (NO) in Raw 264.7 cells.

In the cytotoxicity assay system using the MTT reduction method, on the other hand, the crude extract showed a potent antiproliferative effect on HT-1080 (human fibrosarcoma) and AGS (human gastric cancer). The 85% aq.MeOH fraction of solvent-parititioned fractions exhibited the strongest growth inhibition against HT-1080 and AGS cells. n-Hexane fraction revealed the next strongest inhibition effect on growth of HT-1080 and AGS cells.

Four known compounds, Ilimaquinone (1), Smenotronic acid (2), Smenospongic acid (3), and Pelorol (4) were isolated from the sponge Hyrtios erectus. They were also evaluated for antioxidant, antiproliferative, and antiinflammatory effects, respectively. Compound 1 of them showed the best antioxidant effect: 51.8% inhibition ratio for DPPH radical at 100 μM; 97.3% and 97.5% inhibition ratios for authentic peroxynitrite, and peroxynitrite induced from decomposition of SIN-1 at 50 μM, respectively; 60% reducing power for ferric ion at 1 μM. In addition, all compounds dose-dependently showed the moderate or weak inhibition effect against production of nitric oxide in Raw 264.7 cells stimulated by lipopolysaccharide (LPS).

All isolated compounds (1-4) were tested for their cytotoxicities against human cancer cell lines in vitro using MTT assay. All compounds revealed the significant cytotoxicity against human cancer cell lines. Ilimaquinone (1) and Smenotronic acid (2) displayed the significant cytotoxicites against HT-1080, HT-29, AGS, and MCF-7 cell lines with inhibition ratios of 60, 50, 35, and 50% at 10 μM; 30, 45, 45, and 40% at 10 μM. Smenotronic acid (2) and Smenospongic acid (3) showed the significant cytotoxicities against HT-1080, HT-29, and MCF-7 cell lines with inhibition ratios of 45, 45, and 40% at 10μM; 45, 30, and 30% at 10 μM.