Microbial biofilm indicates a cluster of microorganisms having the capability to display drug resistance property, thereby increasing its proficiency in spreading diseases. In the present study, the antibiofilm potential of thymoquinone, a black seed–producing natural molecule, was contemplated against the biofilm formation by Pseudomonas aeruginosa. Substantial antimicrobial activity was exhibited by thymoquinone against the test organism wherein the minimum inhibitory concentration of the compound was found to be 20 μg/mL. Thereafter, an array of experiments (crystal violet staining, protein count, and microscopic observation, etc.) were carried out by considering the sub-MIC doses of thymoquinone (5 and 10 μg/mL), each of which confirmed the biofilm attenuating capacity of thymoquinone. However, these concentrations did not show any antimicrobial activity. Further explorations on understanding the underlying mechanism of the same revealed that thymoquinone accumulated reactive oxygen species (ROS) and also inhibited the expression of the quorum sensing gene (lasI) in Pseudomonas aeruginosa. Furthermore, by taking up a combinatorial approach with two other reported antibiofilm agents (tetrazine-capped silver nanoparticles and tryptophan), the antibiofilm efficiency of thymoquinone was expanded. In this regard, the highest antibiofilm activity was observed when thymoquinone, tryptophan, and tetrazine-capped silver nanoparticles were applied together against Pseudomonas aeruginosa. These combinatorial applications of antibiofilm molecules were found to accumulate ROS in cells that resulted in the inhibition of biofilm formation. Thus, the combinatorial study of these antibiofilm molecules could be applied to control biofilm threats as the tested antibiofilm molecules alone or in combinations showed negligible or very little cytotoxicity.

微生物生物膜是指具有抗药性的微生物群，从而提高其传播疾病的能力。在本研究中，百里醌是一种产生黑色种子的天然分子，其抗生物膜潜力被认为可以对抗铜绿假单胞菌的生物膜形成. 百里香醌对测试生物表现出显着的抗微生物活性，其中发现化合物的最小抑制浓度为20 μg/mL。此后，通过考虑亚 MIC 剂量的百里醌（5 和 10 μg/mL）进行了一系列实验（结晶紫染色、蛋白质计数和显微镜观察等），每个实验都证实了生物膜衰减能力百里醌。然而，这些浓度没有显示任何抗微生物活性。对其潜在机制的进一步探索表明，百里醌积累活性氧 (ROS) 并抑制铜绿假单胞菌群体感应基因 ( lasI )的表达. 此外，通过与其他两种报道的抗生物膜剂（四嗪封端的银纳米颗粒和色氨酸）结合使用，百里醌的抗生物膜效率得到了提高。在这方面，当将百里香醌、色氨酸和四嗪封端的银纳米粒子一起应用于铜绿假单胞菌时，观察到最高的抗生物膜活性。发现这些抗生物膜分子的组合应用会在细胞中积累 ROS，从而抑制生物膜的形成。因此，这些抗生物膜分子的组合研究可用于控制生物膜威胁，因为单独或组合测试的抗生物膜分子显示出可忽略不计或非常小的细胞毒性。