Althaus Julia B, Jerz Gerold, Winterhalter Peter, Kaiser Marcel, Brun Reto, Schmidt Thomas J
Institut für Pharmazeutische Biologie und Phytochemie (IPBP), University of Münster, Pharma Campus, Corrensstraße 48, D-48149 Münster, Germany.
Institut für Lebensmittelchemie, Technische Universität Braunschweig, Schleinitzstraße 20, D-38106 Braunschweig, Germany.
Molecules. 2014 May 15;19(5):6184-201. doi: 10.3390/molecules19056184.
Buxus sempervirens L. (European Box, Buxaceae) has been used in ethnomedicine to treat malaria. In the course of our screening of plant extracts for antiprotozoal activity, a CH2Cl2 extract from leaves of B. sempervirens showed selective in vitro activity against Plasmodium falciparum (IC50 = 2.79 vs. 20.2 µg/mL for cytotoxicity against L6 rat cells). Separation of the extract by acid/base extraction into a basic and a neutral non-polar fraction led to a much more active and even more selective fraction with alkaloids while the fraction of non-polar neutral constituents was markedly less active than the crude extract. Thus, the activity of the crude extract could clearly be attributed to alkaloid constituents. Identification of the main triterpene-alkaloids and characterization of the complex pattern of this alkaloid fraction was performed by UHPLC/+ESI-QTOF-MS analyses. ESI-MS/MS target-guided larger scale preparative separation of the alkaloid fraction was performed by 'spiral coil-countercurrent chromatography'. From the most active subfraction, the cycloartane alkaloid O-tigloylcyclovirobuxeine-B was isolated and evaluated for antiplasmodial activity which yielded an IC50 of 0.455 µg/mL (cytotoxicity against L6 rat cells: IC50 = 9.38 µg/mL). O-tigloylcyclovirobuxeine-B is thus most significantly responsible for the high potency of the crude extract.
欧洲黄杨（黄杨科）在民族医学中被用于治疗疟疾。在我们对植物提取物进行抗原生动物活性筛选的过程中，欧洲黄杨叶子的二氯甲烷提取物对恶性疟原虫显示出选择性体外活性（对L6大鼠细胞的细胞毒性IC50 = 2.79 对 20.2 µg/mL）。通过酸碱萃取将提取物分离为碱性和中性非极性部分，得到了一个活性更高且更具选择性的含生物碱部分，而非极性中性成分部分的活性明显低于粗提物。因此，粗提物的活性显然可归因于生物碱成分。通过超高效液相色谱/电喷雾电离四极杆飞行时间质谱（UHPLC/+ESI-QTOF-MS）分析对主要三萜生物碱进行了鉴定，并对该生物碱部分的复杂模式进行了表征。通过“螺旋盘管逆流色谱法”对生物碱部分进行了电喷雾串联质谱（ESI-MS/MS）靶向引导的大规模制备分离。从活性最高的亚组分中分离出环阿尔廷烷生物碱O-惕各酰环维罗黄杨碱-B，并对其抗疟活性进行了评估，其IC50为0.455 µg/mL（对L6大鼠细胞的细胞毒性：IC50 = 9.38 µg/mL）。因此，O-惕各酰环维罗黄杨碱-B对粗提物的高效力负有最显著的责任。
