Instituto de Biologia Molecular e Celular, Group of Molecular Biology, Universidade do Porto, Rua do Campo alegre, Porto, Portugal.
Eur J Clin Microbiol Infect Dis. 2010 Jan;29(1):45-50. doi: 10.1007/s10096-009-0817-2. Epub 2009 Oct 8.
The purpose of this study was to investigate the effect of manuka honey on Staphylococcus aureus in order to identify the intracellular target site. The mode of inhibition of manuka honey against S. aureus NCTC 10017 was investigated by determining the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and the effect of time on viability. Structural changes were observed by scanning (SEM) and transmission electron microscopy (TEM) of cells suspended for 4 h at 37 degrees C in 0.05 mM Tris buffer containing 10% (w/v) manuka honey and were compared to cells in buffer alone or buffer containing 10% (w/v) artificial honey (to assess osmotic damage). A bactericidal mode of inhibition for manuka honey on S. aureus was established. Marked structural changes in honey-treated cells were seen only with TEM, where a statistically significant increase in the number of whole cells with completed septa compared to untreated cells were observed (P < 0.05). Structural changes found with TEM suggest that honey-treated cells had failed to progress normally through the cell cycle and accumulated with fully formed septa at the point of cell division without separating. Sugars were not implicated in this effect. The staphylococcal target site of manuka honey involves the cell division machinery.
本研究旨在探讨麦卢卡蜂蜜对金黄色葡萄球菌的作用，以确定其细胞内靶位。通过测定最小抑菌浓度（MIC）、最小杀菌浓度（MBC）以及对活力的时间影响，研究了麦卢卡蜂蜜对金黄色葡萄球菌 NCTC 10017 的抑制模式。将细胞在 37°C 下于 0.05mM Tris 缓冲液中悬浮 4 小时，缓冲液中含有 10%（w/v）麦卢卡蜂蜜，观察细胞的结构变化，并用扫描电子显微镜（SEM）和透射电子显微镜（TEM）进行比较，缓冲液中仅含有细胞或缓冲液含有 10%（w/v）人工蜂蜜（评估渗透压损伤）。确定了麦卢卡蜂蜜对金黄色葡萄球菌的杀菌抑制模式。仅用 TEM 观察到经蜂蜜处理的细胞发生明显的结构变化，与未经处理的细胞相比，完成隔膜的完整细胞数量明显增加（P<0.05）。TEM 发现的结构变化表明，经蜂蜜处理的细胞未能正常通过细胞周期进行分裂，并在细胞分裂点处积累了完全形成的隔膜而没有分离。这一效应与糖无关。麦卢卡蜂蜜的金黄色葡萄球菌靶位涉及细胞分裂机制。
