The aim of this study was to evaluate the antimicrobial activity of twenty-five Plastoquinone analogs synthesized previously in a panel of seven bacterial strains (three Gram-positive and four Gram-negative bacteria) and three fungi. PQ1, which does not contain any substituent(s) on the phenyl ring, was the most potent compound against Staphylococcus epidermidis (8-fold more potent than Cefuroxime, MIC = 1.22 μg/mL). The antifungal profile of all Plastoquinone analogs indicated that three analogs (PQ1, PQ2, and PQ7) displayed the best antifungal activity against Candida albicans, which was about the same activity with the reference standard (MIC = 4.88 μg/mL). The structure-activity relationship study was also carried out to reveal important chemical features. After probing twenty-five Plastoquinone analogs for a potential antimicrobial lead structure, two analogs (PQ1 and PQ25) were selected for further investigation for biofilm evaluation. Based on the tests performed, there was a significant positive correlation between inhibition of the biofilm attachment and time. The results showed that both analogs (PQ1 and PQ25) are able to reduce biofilm mass. Finally, these findings endorse us further efforts to optimize two phenotypes of the Plastoquinone analogs (PQ1 and PQ25) to develop potential antimicrobial drug candidates.

本研究的目的是评估先前在一组七种细菌菌株（三种革兰氏阳性菌和四种革兰氏阴性菌）和三种真菌中合成的 25 种质体醌类似物的抗菌活性。PQ1在苯环上不含任何取代基，是对抗表皮葡萄球菌最有效的化合物（比头孢呋辛强 8 倍，MIC = 1.22  μ g/mL）。所有质体醌类似物的抗真菌特性表明三种类似物（PQ1、PQ2和PQ7）对白色念珠菌显示出最佳的抗真菌活性。，其活性与参考标准品大致相同（MIC = 4.88 μg/mL）。还进行了构效关系研究以揭示重要的化学特征。在探索了 25 种质体醌类似物的潜在抗菌先导结构后，选择了两种类似物（PQ1和PQ25）进行生物膜评估的进一步研究。根据所进行的测试，生物膜附着的抑制与时间之间存在显着的正相关。结果表明，这两种类似物（PQ1和PQ25）都能够减少生物膜质量。最后，这些发现支持我们进一步努力优化质体醌类似物的两种表型（PQ1和PQ25）开发潜在的抗菌药物候选者。