Musuyu Muganza D, Fruth B I, Nzunzu Lami J, Cos P, Cimanga Kanyanga R, Maes L, Pieters L
Faculty of Pharmaceutical Sciences, University of Kinshasa, P.O. Box 212, Kinshasa XI, Democratic Republic of Congo.
Centre for Research and Conservation/KMDA, Koningin Astridplein 20-26, B-2018 Antwerp, Belgium; Faculty of Biology/ Department Biology II, Ludwig Maximilian University of Munich,Großhaderner Straße 2, d-82152 Planegg-Martinsried, Germany.
J Ethnopharmacol. 2015 Nov 4;174:187-94. doi: 10.1016/j.jep.2015.07.034. Epub 2015 Aug 1.
Isolona hexaloba (Pierre) Engl. and Diels (Annonaceae) is traditionally used in D.R. Congo against parasitic diseases including malaria.
Two crude aqueous extracts, 3 crude methanol extracts and 3 crude 80% ethanol extracts from the leaves, root bark and stem bark together with 12 subfractions from the crude 80% ethanol extracts were evaluated in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, T. cruzi, Leishmania infantum and the chloroquine and pyrimethamine resistant K1 strain of Plasmodium falciparum. Their cytotoxic effects against MRC-5 cell lines were also assessed.
Results indicated that the most pronounced activities against T. b. brucei were recorded for the crude methanol extracts of root bark (IC50=1.97 µg/ml; SI>32.49) and leaves (IC50=2.65 µg/ml; SI>24.15). Three samples displayed good activity against T. cruzi: the 80% methanol extract of leaves (IC50=8.33 µg/ml; SI>3.92), its petroleum ether fraction (IC50=8.50 µg/ml; SI=2.52) and the crude aqueous extract of the stem bark (IC50=9.31 µg/ml; SI=3.46). The crude aqueous extract of the leaves exhibited a pronounced and selective activity against L. infantum (IC50=2.00 µg/ml; SI>32). The crude methanol extract of leaves (IC50=6.35 µg/ml; SI>10.10) and the 2 dichloromethane soluble fractions of the 80% ethanol extracts from root bark (IC50=6.96 µg/ml; SI=6.1) and stem bark (IC50=8 µg/ml; SI>8.00) showed good activity and selectivity against L. infantum. The most active samples against Plasmodium falciparum K1 were the leaves crude 80% ethanol extract (0.92 µg/ml) and its fractions: alkaline aqueous (IC50=0.27 µg/ml), 90% methanol (0.90 µg/ml) and dichloromethane (1.04 µg/ml), respectively, with promising selectivity indexes of 35<SI<237. None of all the tested crude extracts and fractions was found to be cytotoxic against MRC-5 cell lines except the petroleum ether soluble fraction from the leaves which displayed a cytotoxic effect (CC50=21.40 µg/ml).
Overall, extracts of I. hexaloba tested here, showed good results concerning parasitic infections such as Chagas' disease, leishmaniasis, malaria and/or sleeping sickness without considerable toxicity. The 80% ethanol extracts from leaves and their fractions turned out to be of special interest as they were the most useful in the treatment of malaria.
六裂伊索木（Isolona hexaloba (Pierre) Engl. and Diels，番荔枝科）在刚果民主共和国传统上用于治疗包括疟疾在内的寄生虫病。
对从叶、根皮和茎皮中提取的两种粗水提取物、三种粗甲醇提取物和三种粗80%乙醇提取物以及粗80%乙醇提取物中的12个亚组分进行体外抗寄生虫活性评估，测试其对布氏布氏锥虫（Trypanosoma brucei brucei）、克氏锥虫（T. cruzi）、婴儿利什曼原虫（Leishmania infantum）以及氯喹和乙胺嘧啶耐药的恶性疟原虫（Plasmodium falciparum）K1株的活性。还评估了它们对MRC - 5细胞系的细胞毒性作用。
结果表明，根皮的粗甲醇提取物（IC50 = 1.97 µg/ml；SI>32.49）和叶的粗甲醇提取物（IC50 = 2.65 µg/ml；SI>24.15）对布氏布氏锥虫的活性最为显著。三个样品对克氏锥虫显示出良好活性：叶的80%甲醇提取物（IC50 = 8.33 µg/ml；SI>3.92）、其石油醚馏分（IC50 = 8.50 µg/ml；SI = 2.52）和茎皮的粗水提取物（IC50 = 9.31 µg/ml；SI = 3.46）。叶的粗水提取物对婴儿利什曼原虫表现出显著的选择性活性（IC50 = 2.00 µg/ml；SI>32）。叶的粗甲醇提取物（IC50 = 6.35 µg/ml；SI>10.10）以及根皮和茎皮的80%乙醇提取物的两个二氯甲烷可溶馏分（根皮IC50 = 6.96 µg/ml；SI = 6.1，茎皮IC50 = 8 µg/ml；SI>8.00）对婴儿利什曼原虫显示出良好的活性和选择性。对恶性疟原虫K1最具活性的样品是叶的粗80%乙醇提取物（0.92 µg/ml）及其馏分：碱性水相（IC50 = 0.27 µg/ml）、90%甲醇（0.90 µg/ml）和二氯甲烷（1.04 µg/ml），选择性指数有前景，为35<SI<237。除了叶的石油醚可溶馏分显示出细胞毒性作用（CC50 = 21.40 µg/ml）外，所有测试的粗提取物和馏分均未发现对MRC - 5细胞系具有细胞毒性。
总体而言，此处测试的六裂伊索木提取物在治疗恰加斯病、利什曼病、疟疾和/或昏睡病等寄生虫感染方面显示出良好效果，且毒性不大。叶的80%乙醇提取物及其馏分特别值得关注，因为它们在疟疾治疗中最为有效。
