Laboratorio de Inmunología de la Reproducción, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.
Centro de Nanociencia y Nanotecnología, Universidad de Santiago de Chile, Santiago, Chile.
Biomed Res Int. 2021 Jan 27;2021:3491831. doi: 10.1155/2021/3491831. eCollection 2021.
We analysed whether the hydroethanolic extracts from leaves of Remy (bailahuen) and Palau (cedron) inhibit the growth and ability of Enteritidis to form biofilms and to adhere to human intestinal epithelial cells. Herein, we first determined the total phenolic content and antioxidant and antibacterial activities of the extracts. Then, Enteritidis was treated with the extracts to analyse biofilm formation by scanning electronic microscopy and the violet crystal test. We also measured the efflux pump activity of Enteritidis since biofilm formation is associated with this phenomenon. Furthermore, the human intestinal cell line Caco-2 was infected with Enteritidis pretreated with the extracts, and 30 min later, the number of bacteria that adhered to the cell surface was quantified. Finally, we determined by qPCR the expression of genes associated with biofilm formation, namely, the diguanilate cyclase AdrA protein gene () and the BapA protein gene (), and genes associated with adhesion, namely, the transcriptional regulator HilA (). The phenolic content and antioxidant and bactericide activities were higher in bailahuen than in the cedron extract. Biofilm formation was inhibited by the extracts in a dose-dependent manner, while the activity of efflux pumps was decreased only with the cedron extract. Adhesion to Caco-2 cells was also inhibited without differences between doses and extracts. The extracts decreased the expression of ; with the cedron extract being the most efficient. The expression of is affected only with the cedron extract. We concluded that hydroethanolic extracts of bailahuen and cedron differentially inhibit the growth of Enteritidis and affect its the ability to form biofilms and to adhere to human intestinal epithelial cells. These results highlight the presence of molecules in bailahuen and cedron with a high potential for the control of the Enteritidis pathogenesis.
我们分析了 Remy（bailahuen）和 Palau（cedron）叶的水醇提取物是否抑制 Enteritidis 的生长和形成生物膜的能力以及黏附人肠上皮细胞的能力。在此，我们首先确定了提取物的总酚含量、抗氧化和抗菌活性。然后，用提取物处理 Enteritidis，通过扫描电子显微镜和紫晶试验分析生物膜的形成。我们还测量了 Enteritidis 的外排泵活性，因为生物膜的形成与这种现象有关。此外，用提取物预处理 Enteritidis 感染人肠细胞系 Caco-2，30 分钟后，定量黏附在细胞表面的细菌数量。最后，通过 qPCR 确定与生物膜形成相关的基因（即二鸟苷酸环化酶 AdrA 蛋白基因 () 和 BapA 蛋白基因 ()）和与黏附相关的基因（即转录调控因子 HilA ()）的表达。bailahuen 提取物中的酚含量、抗氧化和杀菌活性均高于 cedron 提取物。生物膜的形成呈剂量依赖性地被提取物抑制，而外排泵的活性仅在 cedron 提取物中降低。黏附到 Caco-2 细胞也被抑制，且提取物之间无剂量差异。提取物降低了的表达；cedron 提取物最有效。仅 cedron 提取物影响的表达。我们得出结论，bailahuen 和 cedron 的水醇提取物可抑制 Enteritidis 的生长并影响其形成生物膜和黏附人肠上皮细胞的能力。这些结果突出了 bailahuen 和 cedron 中存在具有控制 Enteritidis 发病机制的高潜力的分子。
