Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon.
Nat Prod Res. 2011 Apr;25(7):741-9. doi: 10.1080/14786419.2010.531392.
In vitro biological activities including phytotoxic, antifungal activities as well as acute toxicity of the methanol extract, fractions and/or isolated compounds from the stem bark of Diospyros canaliculata were investigated. Well agar diffusion and macrodilution assays were used for investigating the antifungal activity. A phytotoxicity assay was performed against Lemna minor while an acute toxicity assay was performed in mice via oral administration. As a result, plumbagin (5-hydroxy-2-methyl-1,4-naphtoquinone) and two known pentacyclic triterpenes (lupeol and lupenone) were isolated from the extract. With regards the antifungal activities, the inhibition zones varied from 16.51 to 24.86 mm and from 20.50 to 25.10 mm for the extract and plumbagin, respectively. The minimum inhibitory concentrations of the extract and plumbagin ranged between 12.5-25 and 0.78-1.56 µg mL(-1), respectively. At 50 µg mL(-1), the hexane fraction showed phytotoxic activities similar to paraquat, the standard phytotoxic inhibitor. The extract was found to be non-toxic to mice after administration per os. Based on the current findings, we can conclude that this extract is non toxic, with significant phytotoxic and antifungal properties due to the presence of plumbagin.
对从沟叶榕茎皮的甲醇提取物、馏分和/或分离化合物的体外生物活性进行了研究，包括植物毒性、抗真菌活性以及急性毒性。采用琼脂扩散和大稀释法测定抗真菌活性。对浮萍进行了植物毒性测定，对小鼠进行了口服急性毒性测定。结果从提取物中分离出了 5-羟基-2-甲基-1,4-萘醌（plumbagin）和两种已知的五环三萜（羽扇醇和 lupenone）。就抗真菌活性而言，提取物和 plumbagin 的抑菌圈大小分别为 16.51-24.86mm 和 20.50-25.10mm。提取物和 plumbagin 的最小抑菌浓度范围分别为 12.5-25 和 0.78-1.56μg mL(-1)。在 50μg mL(-1)时，正己烷馏分显示出与百草枯相似的植物毒性活性，百草枯是标准的植物毒性抑制剂。该提取物经口服给药后被发现对小鼠无毒。基于目前的研究结果，我们可以得出结论，由于存在 plumbagin，该提取物具有非毒性、显著的植物毒性和抗真菌特性。
