Walencka Elzbieta, Rozalska Sylwia, Wysokinska Halina, Rozalski Marek, Kuzma Lukasz, Rozalska Barbara
Department of Immunology and Infectious Biology, Institute of Microbiology and Immunology, University of Łodz, Łodz, Poland.
Planta Med. 2007 Jun;73(6):545-51. doi: 10.1055/s-2007-967179.
Two diterpenoids, salvipisone (Salv) and aethiopinone (Aeth), isolated from hairy roots of Salvia sclarea, were tested with respect to their activity against methicillin-resistant Staphylococcus aureus (MRSA) and S. epidermidis (MRSE) strains, cultured as planktonic cells or as adherent biofilms. The standard CLSI method, MTT reduction assay or confocal laser scanning microscopy (CLSM) were used for this purpose and also applied for testing the susceptibility to oxacillin, vancomycin, linezolid and their potential synergy with diterpenoids (evaluated as a fractional inhibitory concentration (FIC) index). Salv and Aeth were shown to be bactericidal or bacteriostatic against S. aureus and S. epidermidis planktonic cultures. Both diterpenoids, at the concentrations of 1/2 MIC, showed synergy with antibiotics representing the beta-lactam, glycopeptide and oxazolidinone groups. None of the antibiotics used at a high concentration killed the staphylococcal biofilms. On the contrary, Salv and Aeth decreased the number of live biofilm cells by 45.7 - 77.1% and slightly reduced the biofilm inhibitory concentration of oxacillin. Diterpenoids also changed the parameters of biofilm morphology, as shown by the CLSM image processing package (PHLIP). It was concluded that salvipisone and aethiopinone (relatively highly lipophilic, log P respectively = 3.4; 4.8) synergized the action of beta-lactam antibiotics towards MRSA and MRSE probably by alteration of cell surface hydrophobicity and cell wall/membrane permeability, but not by changing penicillin-binding protein, PBP2a expression and penicillinase production or by direct binding to the cell wall peptidoglycan and teichoic acids.
从鼠尾草毛状根中分离出的两种二萜类化合物，即鼠尾草苦内酯（Salv）和埃塞俄比亚酮（Aeth），针对它们对耐甲氧西林金黄色葡萄球菌（MRSA）和表皮葡萄球菌（MRSE）菌株的活性进行了测试，这些菌株以浮游细胞或附着生物膜的形式培养。为此使用了标准的CLSI方法、MTT还原测定法或共聚焦激光扫描显微镜（CLSM），并且还用于测试对苯唑西林、万古霉素、利奈唑胺的敏感性以及它们与二萜类化合物的潜在协同作用（以分数抑制浓度（FIC）指数评估）。结果表明，Salv和Aeth对金黄色葡萄球菌和表皮葡萄球菌的浮游培养物具有杀菌或抑菌作用。两种二萜类化合物在1/2 MIC浓度下均与代表β-内酰胺、糖肽和恶唑烷酮类的抗生素表现出协同作用。高浓度使用的任何一种抗生素都不能杀死葡萄球菌生物膜。相反，Salv和Aeth使活生物膜细胞数量减少了45.7 - 77.1%，并略微降低了苯唑西林的生物膜抑制浓度。二萜类化合物还改变了生物膜形态参数，如CLSM图像处理软件包（PHLIP）所示。得出的结论是，鼠尾草苦内酯和埃塞俄比亚酮（相对亲脂性较高，log P分别为 = 3.4；4.8）可能通过改变细胞表面疏水性和细胞壁/膜通透性，而不是通过改变青霉素结合蛋白、PBP2a表达和青霉素酶产生或直接结合细胞壁肽聚糖和磷壁酸，来增强β-内酰胺抗生素对MRSA和MRSE的作用。
