Identification of a Neolignan Glycoside from the Pine Tree, Pinus densiflora Showed Antithrombotic Activity

The constituents from the needles of the pine tree, Pinus densiflora, were purified and investigated for antithrombotic activity. The needles were initially extracted three times with 70% ethanol, and the extract was sequentially fractionated with chloroform and n-butanol. The aqueous layer formed after n-butanol fractionation was subjected to purification by medium pressure and high pressure liquid chromatography. The two neolignans, 2, 3-dihydro-7-hydroxyl-3-hydroxymethyl-2-(4'-hydroxyl -3-methoxyphenyl)-5-benzofuranpropanol-3-O-${\alpha}$-rhamnopyranoside (a neolignan glycoside) and 2, 3-dihyro-3-hydroxymethyl-7-methoxy-2-(4'-hydroxyphenyl-3'-methoxy)-5-benxofuran propanol 4'-O-${\alpha}$-rhamnopyranoside (icariside $E_4$) were identified by $^1H$ and $^{13}C$ NMR spectra. The effect of the purified compounds, the neolignan glycoside and icariside $E_4$ on thrombin inhibition were investigated by measuring thrombin clotting time in plasma. As a result, the clotting of the neolignan glycoside was delayed four times compared to that of icariside $E_4$. In addition, an analysis of the inhibition effect by changing the concentration showed that the clotting time was delayed in accordance with an increase in the concentration of the neolignan glycoside. Furthermore, we examined the interaction of thrombin and fibrinogen to clarify the action mechanism. As a result, the delay of clotting time in the response of thrombin and pure fibrinogen may indicate that neolignan glycosides inhibit the thrombin action in a direct manner, leading to the suppression of fibrin generation.

Pinus densiflora 유래의 항트롬빈 활성을 나타내는 Neolignan Glycoside의 동정

소나무(Pinus densiflora)의 잎의 성분을 분리하여 항트롬빈 활성을 조사하였다. 잎은 70% ethanol로 3회 추출하였으며, 그 추출물은 순차적으로 chloroform과 n-buthanol로 분획하였다. n-buthanol 분획으로부터 얻은 수용성 분획을 MPLC와 HPLC에 의해 분리하였다. 분리한 compound를 $^1H-$과 $^{13}C-NMR$로 동정한 결과 2, 3-dihydro-7-hydroxyl-3-hydroxymethyl-2-(4'-hydroxyl-3-methoxyphenyl)-5-benzofuranpropanol-3-O-${\alpha}$-rhamnopyranoside(a neolignan glycoside)와 2, 3-dihyro-3-hydroxymethyl-7-methoxy-2-(4'-hydroxyphenyl-3'-methoxy)-5-benxofuran propanol 4'-O-${\alpha}$-rhamnopyranoside (icariside $E_4$)의 neolignan 구조임을 확인하였다. 트롬빈 저해활성은 분리된 neolignan glycoside와 icariside $E_4$을 작용하여 혈장안에서 응고시간으로 측정하였다. 그 결과, neolignan glycoside의 응고시간이 icariside $E_4$보다 4배 이상 지연하였다. 저해활성은 neolignan glycoside의 농도가 증가함에 따라 그 시간이 지연되는 것을 확인하였다. 더 나아가 지연기전을 확인하기 위해 thrombin과 순수한 fibrinogen를 반응하였다. 그 결과, 트롬빈과 순수한 피브리노겐의 작용에 의해 응고시간은 지연되었으며, 이는 neolignan glycoside가 피브린형성에 주요한 트롬빈의 활성을 직접 저해하는 것으로 사료된다.