Abstract The aim of this study was to investigate the antibacterial activity, antibiotic-associated synergy, and anti-biofilm activity of the ruthenium complex, cis-[RuCl2 (dppb) (bqdi)]2+ (RuNN). RuNN exhibited antimicrobial activity against Gram-positive bacteria with minimum inhibitory concentration (MIC) values ranging from 15.6 to 62.5 µg ml−1 and minimum bactericidal concentration (MBC) values ranging from 62.5 to 125 µg ml−1. A synergistic effect against Staphylococcus spp. was observed when RuNN was combined with ampicillin, and the range of associated fractional inhibitory concentration index (FICI) values was 0.187 to 0.312. A time-kill curve indicated the bactericidal activity of RuNN in the first 1–5 h. In general, RuNN inhibited biofilm formation and disrupted mature biofilms. Furthermore, RuNN altered the cellular morphology of S. aureus biofilms. Further, RuNN did not cause hemolysis of erythrocytes. The results of this study provide evidence that RuNN is a novel therapeutic candidate to treat bacterial infections caused by Staphylococcus biofilms.

中文翻译：

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双膦酸钌复合物对临床相关细菌的抗菌活性和抗生素协同作用

摘要 本研究的目的是研究钌络合物顺式-[RuCl2 (dppb) (bqdi)]2+ (RuNN) 的抗菌活性、抗生素相关协同作用和抗生物膜活性。RuNN 对革兰氏阳性菌表现出抗菌活性，最小抑菌浓度 (MIC) 值范围为 15.6 至 62.5 µg ml-1，最小杀菌浓度 (MBC) 值范围为 62.5 至 125 µg ml-1。对葡萄球菌的协同作用。当 RuNN 与氨苄青霉素结合时观察到，相关的分数抑制浓度指数 (FICI) 值的范围为 0.187 至 0.312。时间-杀灭曲线表明 RuNN 在前 1-5 小时内的杀菌活性。一般来说，RuNN 抑制生物膜形成并破坏成熟的生物膜。此外，RuNN 改变了 S 的细胞形态。金黄色葡萄球菌生物膜。此外，RuNN 不会引起红细胞溶血。这项研究的结果提供了证据，证明 RuNN 是治疗由葡萄球菌生物膜引起的细菌感染的新型候选药物。