Jatropha curcas is a flowering plant in the genus Jatropha in spurge family, Euphorbiaceae. It is native to American tropics and cultivated in tropical and subtropical regions. Raising J. curcas is very easy because it is a drought resistant, perennial plant that grows even in the marginal and poor soil. Thus, J. curcas has drawn much attention in recent years as a source of seed oil and medicinal plant. Phytochemical studies suggested that J. curcas is a rich source of terpenoid compounds. Among these terpenes, diterpenoid compounds have dominated the research area with respect to their novel chemical structures and medicinal values.

Recently, prof. WANG Mingkui and his team of researchers at Chengdu Institute of Biology, Chinese Academy of Sciences focused on the separation of bioactive compounds from the root bark of J. curcas. Three new diterpenoids, together with jatrophol, curcusone B, curcusone C, curcusone D, 4E-jatrogrossidentadion, 15-epi-4E-jatrogrossidentadion, 2-epihydroxyisojatrogrossidion, jatropholone A and jatropholone B, were isolated based on various column chromatography techniques.

The structures of the new compounds were identified by HR-MS and NMR spectroscopic methods. The configurations were determined by X-ray crystallographic analysis and chemical transformation. According to the skeleton structures, all the isolated compounds can be divided into three categories: curcusone, curculathyrane and jatropholone.

In vitro cytotoxic tests demonstrated that several curcusone and curculathyrane type diterpenoids showed excellent activity against HEPG2 cell lines. However, all the isolates showed no cytotoxic activity against LOVO cancerous cells. Further studies regarding the structure-activity relationships of the diterpenoids from this plant need to be carried out.

The paper entitled ″Diterpenoids from the root bark of Jatropha curcas and their cytotoxic activities″ was published in Phytochemistry Letters (2012, 5, 721-724).