• Korean Journal of Pharmacognosy
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• v.33 no.1 s.128
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• pp.69-73
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• 2002

The methanol extracts of 162 herbal medicines were screened for the inhibitory activity against VHR dualspecificity protein tyrosine phosphatase (DS-PTPase). Seventeen medicinal plants, Scutellaria baicalensis, Cuscuta chinensis, Caesalpinia sappan, Arecae pericarpium, Rubus coreanus, Machilus thunbergii, Amsonia elliptica Cinnamomum cassia, Arisaema erubescens, Pueraria thunbergiana, Dendrobium moniliforme, Mentha arvensis, Peucedanum japonicum, Salvia miltiorrhiza, Leonurus sibiricus, Siegesbeckia orientalis, Prunella vulgaris showed potent VHR DS-PTPase inhibitory activity.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.505-509
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• 2002

In the course of screening program for VHR DS-PTPase (dual-specificity protein tyrosine phosphatase) from natural sources, Gastrodia elata was selected. One compound showing potent inhibitory activity was isolated by the solvent extraction and column chromatography including silica gel, ODS RP-18, Sephades LH-20, and HPLC. This compound was identified as baicalein by several NMR techniques such as $^1H-NMR$, $^{13}C-NMR$, and DEPT. Baicalein showed selective inhibitory activity against VHR DS-PTPase with $IC_{50}=2.4\;{\mu}M$, and showed cytotoxicity against several human cancer cell lines with an $GI_{50}$ of $5.26{\sim}12.93\;{\mu}g/mL$ range, including, melanoma (LOX-IMVI), lung cancer (NCI H23 and A549), colon cancer (HCT 116 and SW 620), prostate cancer (PC-3), and leukemia (MOLT 4F).