School of Science, Monash University Sunway Campus, Bandar Sunway, 46150 Petaling Jaya, Selangor, Malaysia.
BMC Complement Altern Med. 2011 Jan 14;11:3. doi: 10.1186/1472-6882-11-3.
Studies have shown that the barks and roots of some Apocynaceae species have anticancer and antimalarial properties. In this study, leaf extracts of five selected species of Apocynaceae used in traditional medicine (Alstonia angustiloba, Calotropis gigantea, Dyera costulata, Kopsia fruticosa and Vallaris glabra) were assessed for antiproliferative (APF) and antiplasmodial (APM) activities, and analysed for total alkaloid content (TAC), total phenolic content (TPC) and radical-scavenging activity (RSA). As V. glabra leaf extracts showed wide spectrum APF and APM activities, they were further screened for saponins, tannins, cardenolides and terpenoids.
APF and APM activities were assessed using the sulphorhodamine B and lactate dehydrogenase assays, respectively. TAC, TPC and RSA were analysed using Dragendorff precipitation, Folin-Ciocalteu and DPPH assays, respectively. Screening for saponins, tannins, cardenolides and terpenoids were conducted using the frothing, ferric chloride, Kedde and vanillin-H2SO4 tests, respectively.
Leaf extracts of A. angustiloba, C. gigantea and V. glabra displayed positive APF activity. Dichloromethane (DCM) extract of C. gigantea, and DCM and DCM:MeOH extracts of V. glabra showed strong APF activity against all six human cancer cell lines tested. DCM extract of A. angustiloba was effective against three cancer cell lines. Against MCF-7 and MDA-MB-231 cell lines, DCM extract of C. gigantea was stronger than standard drugs of xanthorrhizol, curcumin and tamoxifen. All five species were effective against K1 strain of Plasmodium falciparum and three species (C. gigantea, D. costulata and K. fruticosa) were effective against 3D7 strain. Against K1 strain, all four extracts of V. glabra displayed effective APM activity. Extracts of D. costulata were effective against 3D7 strain. Selectivity index values of extracts of A. angustiloba, C. gigantea and V. glabra suggested that they are potentially safe for use to treat malaria. Extracts of K. fruticosa had the highest TAC while D. costulata had the highest TPC and RSA. Phytochemical screening of extracts of V. glabra also showed the presence of terpenoids, tannins and saponins.
Leaf extracts of C. gigantea and V. glabra showed great promise as potential candidates for anticancer drugs as they inhibited the growth of all six cancer cell lines. Against K1 strain of P. falciparum, all four extracts of V. glabra displayed effective APM activity. The wide spectrum APF and APM activities of V. glabra are reported for the first time and this warrants further investigation into its bioactive compounds.
研究表明，夹竹桃科的一些树皮和根具有抗癌和抗疟的特性。在这项研究中，五种传统医学中使用的夹竹桃科植物的叶提取物（阿尔斯通 angustiloba、长春花、迪耶拉 costulata、考普西亚 fruticosa 和瓦拉里斯 glabra）被评估了抗增殖（APF）和抗疟（APM）活性，并分析了总生物碱含量（TAC）、总酚含量（TPC）和自由基清除活性（RSA）。由于 V. glabra 叶提取物表现出广谱的 APF 和 APM 活性，因此进一步筛选了它们的皂甙、单宁、强心苷和萜类化合物。
使用磺基罗丹明 B 和乳酸脱氢酶测定法分别评估 APF 和 APM 活性。使用 Dragendorff 沉淀、Folin-Ciocalteu 和 DPPH 测定法分别分析 TAC、TPC 和 RSA。使用泡沫、三氯化铁、Kedde 和香草醛-H2SO4 试验分别对皂甙、单宁、强心苷和萜类化合物进行筛选。
A. angustiloba、C. gigantea 和 V. glabra 的叶提取物表现出阳性的 APF 活性。长春花的二氯甲烷（DCM）提取物和 V. glabra 的 DCM 和 DCM：甲醇提取物对所有六种测试的人癌细胞系均表现出强烈的 APF 活性。A. angustiloba 的 DCM 提取物对三种癌细胞系有效。对于 MCF-7 和 MDA-MB-231 细胞系，长春花的 DCM 提取物比黄樟素、姜黄素和他莫昔芬的标准药物更强。五种物种均对恶性疟原虫 K1 株有效，三种物种（长春花、迪耶拉 costulata 和考普西亚 fruticosa）对 3D7 株有效。对于 K1 株，V. glabra 的四种提取物均表现出有效的 APM 活性。D. costulata 的提取物对 3D7 株有效。A. angustiloba、C. gigantea 和 V. glabra 的提取物的选择性指数值表明，它们可能安全用于治疗疟疾。K. fruticosa 的提取物具有最高的 TAC，而 D. costulata 的提取物具有最高的 TPC 和 RSA。V. glabra 的提取物的植物化学筛选还表明存在萜类化合物、单宁和皂甙。
长春花和 V. glabra 的叶提取物显示出作为抗癌药物的潜在候选物的巨大希望，因为它们抑制了所有六种癌细胞系的生长。对于恶性疟原虫 K1 株，V. glabra 的四种提取物均表现出有效的 APM 活性。V. glabra 的广谱 APF 和 APM 活性是首次报道的，这需要进一步研究其生物活性化合物。
