Borges Anabela, Serra Sofia, Cristina Abreu Ana, Saavedra Maria J, Salgado António, Simões Manuel
a LEPABE, Faculty of Engineering, Department of Chemical Engineering , University of Porto , Porto , Portugal.
Biofouling. 2014 Feb;30(2):183-95. doi: 10.1080/08927014.2013.852542. Epub 2013 Dec 18.
Quorum sensing (QS) is an important regulatory mechanism in biofilm formation and differentiation. Interference with QS can affect biofilm development and antimicrobial susceptibility. This study evaluates the potential of selected phytochemical products to inhibit QS. Three isothiocyanates (allylisothiocyanate - AITC, benzylisothiocyanate - BITC and 2-phenylethylisothiocyanate - PEITC) and six phenolic products (gallic acid - GA, ferulic acid - FA, caffeic acid - CA, phloridzin - PHL, (-) epicatechin - EPI and oleuropein glucoside - OG) were tested. A disc diffusion assay based on pigment inhibition in Chromobacterium violaceum CV12472 was performed. In addition, the mechanisms of QS inhibition (QSI) based on the modulation of N-acyl homoserine lactone (AHLs) activity and synthesis by the phytochemicals were investigated. The cytotoxicity of each product was tested on a cell line of mouse lung fibroblasts. AITC, BITC and PEITC demonstrated a capacity for QSI by modulation of AHL activity and synthesis, interfering the with QS systems of C. violaceum CviI/CviR homologs of LuxI/LuxR systems. The cytotoxic assays demonstrated low effects on the metabolic viability of the fibroblast cell line only for FA, PHL and EPI.
群体感应（QS）是生物膜形成和分化过程中的一种重要调节机制。干扰群体感应会影响生物膜的发育和抗菌敏感性。本研究评估了所选植物化学产物抑制群体感应的潜力。测试了三种异硫氰酸酯（烯丙基异硫氰酸酯 - AITC、苄基异硫氰酸酯 - BITC和2-苯乙基异硫氰酸酯 - PEITC）以及六种酚类产物（没食子酸 - GA、阿魏酸 - FA、咖啡酸 - CA、根皮苷 - PHL、（-）表儿茶素 - EPI和橄榄苦苷 - OG）。基于紫色杆菌CV12472色素抑制的纸片扩散法进行了实验。此外，还研究了植物化学物质基于对N-酰基高丝氨酸内酯（AHLs）活性和合成的调节来抑制群体感应（QSI）的机制。在小鼠肺成纤维细胞系上测试了每种产物的细胞毒性。AITC、BITC和PEITC通过调节AHL活性和合成表现出群体感应抑制能力，干扰了紫色杆菌CviI/CviR同源物的LuxI/LuxR系统的群体感应系统。细胞毒性试验表明，仅FA、PHL和EPI对成纤维细胞系的代谢活力影响较小。
