Kuete Victor, Nana Frédéric, Ngameni Bathélémy, Mbaveng Armelle Tsafack, Keumedjio Félix, Ngadjui Bonaventure Tchaleu
Department of Biochemistry, Faculty of Science, University of Dschang, B.P. 67 Dschang, Cameroon.
J Ethnopharmacol. 2009 Jul 30;124(3):556-61. doi: 10.1016/j.jep.2009.05.003. Epub 2009 May 18.
This study was designed to investigate the antimicrobial activities of the methanol extracts from the stem bark of Ficus ovata (FOB), fractions (FOB1-6) and compounds isolated following bio-guided fractionation [3-friedelanone (1), taraxeryl acetate (2), betulinic acid (3), oleanoïc acid (4), 2-hydroxyisoprunetin (5), 6,7-(2-isopropenyl furo)-5,2,4-trihydroxyisoflavone (6), Cajanin (7) and protocatechuic acid (8)].
The micro-dilution method was used for the determination of the minimal inhibition concentration (MIC) and the minimal microbicidal concentration (MMC) against fungi (two species), gram-positive (three species) and gram-negative bacteria (five species).
The results of the MIC determinations indicated that the crude extract (FOB), fractions FOB2 and FOB4 as well as compound 5 were active on the entire studied organisms. Other samples showed selective activity, fractions FOB1, FOB3 and FOB5 being active against 50% of the tested microbial species while FOB6 was active on 40%. Compounds 8, 6, 2 and 7 prevented the growth of 80%, 70%, 50% and 20% of the organisms respectively. The lowest MIC value (156 g/ml) observed with the crude extract was recorded on Streptococcus faecalis, Candida albicans and Microsporum audouinii. The corresponding value for fractions (39 microg/ml) was noted with FOB4 against Staphylococcus aureus, while that of the tested compounds (10 microg/ml) was observed with compound 8 on Microsporum audouinii. The results of the MMC determination suggested that the cidal effect of most of the tested samples on the studied microorganisms could be expected.
The overall results provided evidence that the studied plant extract, as well as some of the isolated compounds might be potential sources of new antimicrobial drug.
本研究旨在调查卵形榕茎皮甲醇提取物、各馏分（FOB1 - 6）以及生物导向分馏后分离得到的化合物[3 - 羽扇豆酮（1）、蒲公英赛醇乙酸酯（2）、桦木酸（3）、齐墩果酸（4）、2 - 羟基异补骨脂素（5）、6,7 -（2 - 异丙烯基呋喃）- 5,2,4 - 三羟基异黄酮（6）、木豆素（7）和原儿茶酸（8）]的抗菌活性。
采用微量稀释法测定对真菌（两种）、革兰氏阳性菌（三种）和革兰氏阴性菌（五种）的最低抑菌浓度（MIC）和最低杀菌浓度（MMC）。
MIC测定结果表明，粗提物（FOB）、馏分FOB2和FOB4以及化合物5对所有研究的生物体均有活性。其他样品表现出选择性活性，馏分FOB1、FOB3和FOB5对50%的测试微生物物种有活性，而FOB6对40%的测试微生物物种有活性。化合物8、6、2和7分别抑制80%、70%、50%和20%的生物体生长。粗提物观察到的最低MIC值（156 μg/ml）记录在粪肠球菌、白色念珠菌和奥杜盎小孢子菌上。馏分（39 μg/ml）中FOB4对金黄色葡萄球菌的相应值被记录到，而测试化合物（10 μg/ml）中化合物8对奥杜盎小孢子菌的相应值被观察到。MMC测定结果表明，大多数测试样品对所研究微生物的杀菌作用是可以预期的。
总体结果提供了证据，表明所研究的植物提取物以及一些分离得到的化合物可能是新型抗菌药物的潜在来源。
