木賊對 Staphylococcus simulans 之抗菌活性研究 因著人類濫用抗生素，細菌對抗生素產生抗藥性，造成很嚴重的問題。

葡萄球菌對人類和動物造成普遍性的感染， Staphylococcus simulans通常在被圈養的動物 ( 牛和豬 ) 身上被發現，是伺機性病原菌的一種，會造成表皮炎、耳炎和乳房炎，甚至 Staphylococcus simulans 也被發現在成人身上，引發骨炎、關節炎甚至的敗血症。在這項研究，我們篩選了經 50% 乙醇萃取的八十七種傳統中藥材對產生青黴素抗藥性 Staphylococcus simulans(PRSS) 進行抗菌活性檢測，使用瓊脂紙錠擴散法和連續稀釋法來判斷最小抑制濃度，結果發現木賊 (Equisetum hiemale L.) 具有最佳抗菌活性，對 PRSS 的最小抑制濃度為 384 ug/ml 。利用分配方式分成正己烷層、乙酸乙酯層、正丁醇層和水層，發現正己烷層表現出 PRSS 的最小抑制濃度為 256 ug/ml ，所以分離正己烷層，分離出三個具有抗 Staphylococcus simulans 活性的化合物。經結構鑑定與抑菌活性評估，發現 CP2 (saringosterol) 抑菌效果最佳， CP3 (Aristophyll-C) 次之，其對 PRSS 的最小抑制濃度分別達 32 ug/ml 、 64μg/ml 。在抗生素與活性成分合併方面， CP2 在 8 μg/ml 合併 penicillin 4 μg/ml 及 CP3 在 16 μg/ml 合併 penicillin 16 μg/ml 對 PRSS 有抑制生長的效果；因此 CP2 、 CP3 在抗生物質的開發上具有相當大的潛力。

The antibacterial activity of . Equisetum hiemale L.

against Staphylococcus simulans Because people abuse antibiotics, bacterial resistance to antibiotics becomes a serious global p

roblem. Staphylococci are ubiquitous microorganisms important in human and animal infections. Staphylococcus simulans is commonly found in domesticated animals (cattle and swine), that is opportunistic pathogens, in the pathology of epidermitis, otitis and mastitis.Moreover Staphylococcus simulans was identified as the etiological agent of osteomyelitis and septic arthritis in an adult male. In this study, we screened antibacterial activities of 50% ethanolic extracts 87 traditional Chinese medicines to penicillin-resistant Staphylococcus simulans (PRSS), and used disc agar diffusion method, broth dilution method determination of minimum inhibitory concentrations (MICs). The results showed that Equisetum hiemale L. had the best antibacterial activity, and demonstrated the MICs of 384 ug/ml to PRSS. The extract were fractionated into n-Hexane, ethyl acetate, n-Butanol, H2O. The n-Hexane fraction showed MICs of 256 ug/ml to PRSS. We isolated the n-Hexane fraction to get three active compounds against staphylococcus simulans and determined the structure based on the analysis of NMR spectra. We found saringosterol and Aristophyll-C can effectively resist PRSS with MIC of 32 ug/ml and 64 ug/ml individually.Penicillin G 8 ug/ml combined CP2 4 ug/ml and Penicillin G 16 ug/ml combined CP3 16 ug/ml would be to resist PRSS. Conclude the above advantages, the CP2 and CP3 have the potential ability for the development of future antibacterial agent. Key word: staphylococcus simulans; Equisetum hiemale L.; saringosterol; PRSS