Ha-Na Lyu

Corrigendum: Ursolic acid exerts anti-cancer activity by suppressing vaccinia-related kinase 1-mediated damage repair in lung cancer cells

Many mitotic kinases have been targeted for the development of anti-cancer drugs, and inhibitors of these kinases have been expected to perform well for cancer therapy. Efforts focused on selecting good targets and finding specific drugs to target are especially needed, largely due to the increased frequency of anti-cancer drugs used in the treatment of lung cancer. Vaccinia-related kinase 1 (VRK1) is a master regulator in lung adenocarcinoma and is considered a key molecule in the adaptive pathway, which mainly controls cell survival. We found that ursolic acid (UA) inhibits the catalytic activity of VRK1 via direct binding to the catalytic domain of VRK1. UA weakens surveillance mechanisms by blocking 53BP1 foci formation induced by VRK1 in lung cancer cells, and possesses synergistic anti-cancer effects with DNA damaging drugs. Taken together, UA can be a good anti-cancer agent for targeted therapy or combination therapy with DNA damaging drugs for lung cancer patients.

Lignans from the fruits of the red pepper ( Capsicum annuum L.) and their antioxidant effects

The fruits of Capsicum annuum were extracted using 80% aqueous MeOH, and fractionated using EtOAc and water. Repeated column chromatography using silica gel, octadecyl silica gel, and Sephadex LH-20 for the EtOAc fraction led to the isolation of a new lignan glycoside and a known one, icariside E5. From the results of spectroscopic data, including EIMS, FABMS, UV, IR, 1H and 13C-NMR, DEPT, and 2D-NMR (COSY, HSQC, HMBC), the chemical structure of the new lignan glycoside was determined as (8R)-isodehydrodiconiferyl alcohol-4′-O-(6″-vanilloyl)-β-D-glucopyranoside named vanilloylicariside E5. All isolated compounds were tested for antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Icariside E5 (2) and (8R)-Isodehydrodiconiferyl alcohol (3) exhibited a strong scavenging effect on DPPH (2: IC50=42.1 µM, 3: IC50=4.5 µM).

Sterols from the leafy culms of Desmostachya bipinnata

0009-3130/11/4705-0852 2011 Springer Science+Business Media, Inc. Graduate School of Biotechnology, Institute of Life Sciences & Resources, Kyung Hee University, Yongin 446-701, Korea, fax: 82 31 204 8116, e-mail: nibaek@khu.ac.kr. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 744–745, September–October, 2011. Original article submitted May 19, 2010. Chemistry of Natural Compounds, Vol. 47, No. 5, November, 2011 [Russian original No. 5, September–October, 2011]

Tellimoside, a flavonol glycoside from Brasenia schreberi, inhibits the growth of cyanobacterium (Microcystis aeruginosa LB 2385)

Principal components of aquatic plants responsible for inhibiting the growth of Microcystis aeruginosa, a blue-green alga (cyanobacterium) were determined. Methanol extracts of Brasenia schreberi showed strong inhibitory activity against the growth of the cyanobacterium. Two purified flavonoids were afforded through repeated column chromatographies. The compounds were determined as quercetin (1) and quercetin 3-O-(6″-galloyl)-β-d-glucopyranoside, tellimoside (2) by the interpretation of spectroscopic data including NMR, MS, and IR. Compounds 1 and 2 were first isolated from Brasenia schreberi. In addition, compound 2 showed very strong inhibitory activity against the growth of M. Aeruginosa.