Research Center for the Prevention and Treatment of Drug Resistant Microbial Infecting, Youjiang Medical University for Nationalities, Baise 533000, China.
School of Pharmacy, Youjiang Medical University for Nationalities, 98 Chengxiang Road, Baise 533000, China.
Molecules. 2022 Aug 27;27(17):5519. doi: 10.3390/molecules27175519.
Quorum sensing (QS) plays an important role in the production of virulence factors and pathogenicity in pathogenic bacteria and is, therefore, a hopeful target to fight against bacterial infections. During our search for natural QS inhibitors, two new xanthonolignoids ( and ), each existing as a racemic mixture, one new simple oxygenated xanthone (), and eight known analogs (-, -) were isolated from Linn. Chiral separation of yielded a pair of enantiomers and . The structures of these compounds were elucidated by spectroscopic analysis and ECD (electrostatic circular dichroism) calculations. All isolates were evaluated for their QS inhibitory activity against . Both and exhibited the most potent QS inhibitory effects with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 31.25 and 62.5 μM, respectively. Crystal violet staining was used to further evaluate the biofilm inhibition potential of compounds , and , and the formation of biofilms increased with decreasing drug concentration in a classic dose-dependent manner. The results of a cytotoxicity assay revealed that compounds , and exhibited no cytotoxic activity on PC-12 cells at the tested concentration.
群体感应（QS）在致病菌毒力因子和致病性的产生中起着重要作用，因此是对抗细菌感染的有希望的靶点。在我们寻找天然 QS 抑制剂的过程中，从 Linn.中分离得到了两个新的黄烷酮（和），每个都作为外消旋混合物存在，一个新的简单含氧黄烷酮（）和八个已知类似物（-，-）。对进行手性分离得到了一对对映异构体和。通过光谱分析和 ECD（电致圆二色性）计算阐明了这些化合物的结构。所有分离物都评估了它们对的 QS 抑制活性。和都表现出最强的 QS 抑制作用，最低抑菌浓度（MIC）和最低杀菌浓度（MBC）值分别为 31.25 和 62.5 μM。结晶紫染色进一步评估了化合物、和的生物膜抑制潜力，生物膜的形成随着药物浓度的降低而呈经典的剂量依赖性增加。细胞毒性测定的结果表明，在所测试的浓度下，化合物、和对 PC-12 细胞没有细胞毒性。
