Shi Yong Ryu

Antitumor activity of some phenolic components in plants

The activity-guided fractionation of some medicinal plants led to yield five kinds of natural stilbene compounds namely 3,5-dihydroxy-4′-methoxystillbene(I), rhapontigenin(II), resveratrol (III), rhaponticin(IV) and piceid(V) and two common flavonoids, apigenin(VI) and luteolin(VII) as active principles of the antitumor property, in vitro, against five kinds of human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT15.

Antitumor activity ofPsoralea corylifolia

The activity-oriented fractionation ofPsoralea corylifolia led to an isolation of a (+)-bakuchiol1 as an active principle of its antitumoral propertyin vitro.1 was observed to exhibit a mild cytotoxicity against five kinds of cultured human cancer cell lines,i.e. the A549, SK-OV-3, SK-MEL-2, XF498 and HCT15. The synthesized 2,3-epoxide of (+)-bakuchiol3 showed the similar activity as the (+)-bakuchiol1, whereas the other oxidation derivatives4 and5 including the acetyl-(+)-bakuchiol2 showed a decreased activity.

Antitumor triterpenes from medicinal plants

Thirteen kinds of naturally occurring or derivatised triterpenes, reported to have an antitumoral property, were reinvestigated on the basis of their direct cytotoxicity or the inhibitory activity on cell growth against five kinds of cultured human tumor cells,i. e., A-549, SK-OV-3, SK-MEL-2, XF498 and HCT15,in vitro. Ursonic acidIII, betulinic acidVIII, betulonic acidX and glycyrrhetinic acidXI were exhibited a marked inhibition on cell growth.

Antiviral triterpenes fromPrunella vulgaris

Two triterpenes 1 and 2 with antiviral activity againstHerpes simplex virus type 1in vitro were isolated fromPrunella vulgaris. Each compound caused a significant reduction in viral cytopathic effect whenvero cells were exposed to them for 72 hours after viral challenge. They were identified asbetulinic acid(1) and 2α, 3α-dihydroxyurs-12-en-28-oic acid(2) on the basis of their spectroscopic properties. The antiviral activity of them was estimated as EC50=30 μg/ml(1) and 8 μg/ml(2), respectively by plaque reduction assay.

Antiviral activity of triterpenoid derivatives

Abstract3-Oxo or/and 11-oxo derivatives of natural 3-hydroxy triterpenes,i.e., 3-oxoursolic acidIa, 11-oxoursolic acidIb, 3,11-dioxoursolic acidIc, 3-oxobetulinic acidIIa and 3-oxopomolic acidVIa were exhibited to show an increased anti-HSV-1 activityin vitro, four to ten times as much as corresponding parent 3-hydroxy compounds.

Antitumor activity ofTrichosanthes kirilowii

The activity-directed fractionation upon the MeOH extract of the root ofTrichosanthes kirilowii led to the isolation of eight cucurbitane triterpenes namely cucurbitacin B (I), isocucurbitacin B (II), cucurbitacin D (III), isocucurbitacin D (IV), 3-epi-isocucurbitacin B (V), dihydrocucurbitacin B (VI), dihydroisocucurbitacin B (VII) and dihydrocucurbitacin E (VIII), as active principles. All isolates were shown to exhibit significant cytotoxicity against cultured human tumor cells, including A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT 15, with an exceptionally high potency.

Cytotoxic constituents ofSorbaria sorbifolia var.stellipila.

The acivity-guided fractionation upon the MeOH extract of the aerial parts ofSorbaria sorbifolia var.stellipila led to the isolation of two cucurbitacin-compounds, cucurbitacin D and cucurbitacin F, as active principles. Two compounds were shown to exhibit significant cytotoxicity against cultured human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498, and HCT 15.

The structure of kushenol M fromSophora flavescens

The linkage pattem of two side chainsi.e., a isopentenyl and a lavandulyl group in kushenol M(I), a flavonoid fromSophora flavescens was established by the aid of 2-D NMR techniques, especially DEPT,13C−1H COSY and COLOC experiments. Thus,I was unequivocally determined as (2R,3R)-5,7,2′,4′-tetrahydroxy-6-isopentenyl-8-lavandulylflavanonol.