Tan Lim An Margarete, Oyong Glenn G, Tan Maria Carmen S, Chang Shen Chien, Ragasa Consolacion Y, Cabrera Esperanza C
Biology Department, College of Science, De La Salle University, Manila, Philippines.
School of Medical Technology, Centro Escolar University, Manila, Philippines.
Heliyon. 2021 May 10;7(5):e07002. doi: 10.1016/j.heliyon.2021.e07002. eCollection 2021 May.
(Burm f.) Nees is a tropical plant native to Southeast Asia that has been used as an effective remedy for a wide variety of illnesses in traditional Chinese and Ayurvedic medicine. The antimicrobial activity of its crude extract had been shown to be due to its quorum quenching activity. The study determined the effect of purified extracted compounds from the leaf of A. paniculata, namely: andrographolide, 14-deoxyandrographolide, 14-deoxy-12-hydroxyandrographolide and neoandrographolide on quorum sensing-mediated virulence mechanisms in clinical isolates of metallo-β-lactamase (MβL)-producing . Their effect on the expression of the gene, which codes for LasR, a transcription activator protein of the quorum sensing system in was also determined using RT-qPCR. All the pure compounds significantly decreased the biofilm formation, protease production and swarming motility of the isolates compared to the untreated controls (p < 0.05). Results of the RT-qPCR assay showed that all compounds significantly downregulated the expression of compared to the untreated control (p < 0.05), supporting the position that the lower virulence activities of the treated group were due to quorum quenching activity of the pure compounds. Multiple comparisons using Tukey's HSD analysis revealed that the means of the relative expression of of the isolates treated with the different compounds were not significantly different from each other (p > 0.05), suggesting equal potencies. Results show the potential of the isolated pure compounds from A. paniculata for use as antimicrobial agents as a result of their quorum quenching activities.
（Bur m f.）Nees是一种原产于东南亚的热带植物，在传统中医和阿育吠陀医学中，它被用作治疗多种疾病的有效药物。其粗提物的抗菌活性已被证明归因于其群体感应淬灭活性。该研究确定了从穿心莲叶片中纯化提取的化合物，即穿心莲内酯、14-去氧穿心莲内酯、14-去氧-12-羟基穿心莲内酯和新穿心莲内酯对产金属β-内酰胺酶（MβL）临床分离株中群体感应介导的毒力机制的影响。还使用RT-qPCR确定了它们对编码群体感应系统转录激活蛋白LasR的基因在中的表达的影响。与未处理的对照相比，所有纯化合物均显著降低了分离株的生物膜形成、蛋白酶产生和群集运动性（p<0.05）。RT-qPCR分析结果表明，与未处理的对照相比，所有化合物均显著下调了的表达（p<0.05），支持了处理组较低的毒力活性归因于纯化合物的群体感应淬灭活性这一观点。使用Tukey's HSD分析进行的多重比较显示，用不同化合物处理的分离株的相对表达平均值彼此之间无显著差异（p>0.05），表明效力相同。结果表明，从穿心莲中分离出的纯化合物因其群体感应淬灭活性而具有用作抗菌剂的潜力。
