Department of Pharmacognosy, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt.
Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt.
Molecules. 2020 Mar 16;25(6):1341. doi: 10.3390/molecules25061341.
Bacterial resistance represents one of the emerging obstacles in plants, animals, and humans that impairs treatment with antibacterial agents. Targeting of the bacterial quorum sensing system is one of the strategies to overcome this problem. Recently, research has been focused on natural and food components which can function as quorum sensing inhibitors. In this study, a methanol extract from stem bark was phytochemically profiled by LC-MS analysis. This resulted in the identification of 38 secondary metabolites with (epi)catechin-(epi)catechin, epicatechin, tremulacin, salicortin, and trichocarposide as the major constituents. The extracts of both stem bark and the previously profiled flower of were tested for anti-quorum sensing activity in a common and widely distributed pathogen . The natural products inhibited swimming and swarming motilities, as well as proteolytic and hemolytic activities in a dose-dependent manner. Molecular docking of the constituents from both extracts against the quorum sensing controlling systems Lasl/LasR, rhll/rhlR, and PQS/MvfR showed that epicatechin, (epi)catechin-(epi)catechin, -hydroxy benzoyl galloyl glucose, -hydroxy benzoyl protocatechuic acid glucose, and caffeoylmalic acid could be the main active components. This study supports the importance of secondary metabolites, especially polyphenols, as quorum sensing inhibitors.
细菌耐药性是植物、动物和人类面临的新兴障碍之一，它会影响抗菌药物的治疗效果。靶向细菌群体感应系统是克服这一问题的策略之一。最近，研究集中在可以作为群体感应抑制剂的天然和食物成分上。在这项研究中，通过 LC-MS 分析对茎皮的甲醇提取物进行了植物化学分析。结果鉴定出 38 种次生代谢产物，其中（表）儿茶素-（表）儿茶素、表儿茶素、震颤素、水杨甙和三萜糖苷是主要成分。茎皮和先前分析过的花的提取物都在一种常见且广泛分布的病原体 中测试了抗群体感应活性。天然产物以剂量依赖的方式抑制游泳和群集运动以及蛋白水解和溶血活性。从两种提取物中针对群体感应控制系统 Lasl/LasR、rhll/rhlR 和 PQS/MvfR 的成分进行分子对接表明，表儿茶素、（表）儿茶素-（表）儿茶素、-羟基苯甲酰基没食子酰葡萄糖、-羟基苯甲酰基原儿茶酸葡萄糖和咖啡酰马来酸可能是主要的活性成分。这项研究支持了次生代谢产物（特别是多酚）作为群体感应抑制剂的重要性。
