Ndi Chi P, Semple Susan J, Griesser Hans J, Pyke Simon M, Barton Mary D
Sansom Institute, School of Pharmacy and Medical Sciences, University of South Australia, Frome Road, Adelaide, SA 5000, Australia.
Phytochemistry. 2007 Nov;68(21):2684-90. doi: 10.1016/j.phytochem.2007.05.039. Epub 2007 Jul 12.
We report a search for antimicrobial compounds in the Australian plant Eremophila serrulata. Bioassay directed fractionation of a diethyl ether extract prepared from the leaves of E. serrulata led to the isolation of two compounds, an omicron-naphthoquinone, 9-methyl-3-(4-methyl-3-pentenyl)-2,3-dihydronaphtho[1,8-bc]pyran-7,8-dione (2), and a serrulatane diterpenoid, 20-acetoxy-8-hydroxyserrulat-14-en-19-oic acid (3). Two other known serrulatane-type diterpenoids, 8,20-dihydroxyserrulat-14-en-19-oic acid (4) and 8,20-diacetoxyserrulat-14-en-19-oic acid (5) were also isolated. None of these compounds had previously been tested for antimicrobial activity. Compounds 2-5 showed antimicrobial activity against Staphylococcus aureus (ATCC 29213) with minimum inhibitory concentrations (MICs) ranging from 15.6 to 250mug/mL. Compound 2 was the most active with an MIC of 15.6mug/mL and a minimum bactericidal concentration (MBC) of 125mug/mL. This compound also showed antimicrobial activity against other Gram-positive bacteria including Streptococcus pyogenes, and Streptococcus pneumoniae. No activity was observed for this compound against all Gram-negative bacteria tested.
我们报道了对澳大利亚植物锯齿沙戟中抗菌化合物的研究。对从锯齿沙戟叶片制备的二乙醚提取物进行生物测定导向的分级分离，得到了两种化合物，一种是邻萘醌，9-甲基-3-(4-甲基-3-戊烯基)-2,3-二氢萘并[1,8-bc]吡喃-7,8-二酮（2），以及一种锯齿烷二萜，20-乙酰氧基-8-羟基锯齿-14-烯-19-酸（3）。还分离出了另外两种已知的锯齿烷型二萜，8,20-二羟基锯齿-14-烯-19-酸（4）和8,20-二乙酰氧基锯齿-14-烯-19-酸（5）。这些化合物以前均未进行过抗菌活性测试。化合物2-5对金黄色葡萄球菌（ATCC 29213）表现出抗菌活性，最低抑菌浓度（MIC）范围为15.6至250μg/mL。化合物2活性最强，MIC为15.6μg/mL，最低杀菌浓度（MBC）为125μg/mL。该化合物对包括化脓性链球菌和肺炎链球菌在内的其他革兰氏阳性菌也表现出抗菌活性。对所有测试的革兰氏阴性菌均未观察到该化合物的活性。
