Institute of Botany, Leibniz University Hannover, D-30419 Hannover, Germany.
Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, 20133 Milano, Italy.
Int J Mol Sci. 2019 Jul 19;20(14):3549. doi: 10.3390/ijms20143549.
The extracts of two mangrove species, and , have been analyzed at sub-lethal concentrations for their potential to modulate biofilm cycles (i.e., adhesion, maturation, and detachment) on a bacterium, yeast, and filamentous fungus. Methanolic leaf extracts were also characterized, and MS/MS analysis has been used to identify the major compounds. In this study, we showed the following. (i) Adhesion was reduced up to 85.4% in all the models except for , where adhesion was promoted up to 5.10-fold. (ii) Both the sum and ratio of extracellular polysaccharides and proteins in mature biofilm were increased up to 2.5-fold and 2.6-fold in comparison to the negative control, respectively. Additionally, a shift toward a major production of exopolysaccharides was found coupled with a major production of both intracellular and extracellular reactive oxygen species. (iii) Lastly, detachment was generally promoted. In general, the extract had a higher bioactivity at lower concentrations than the extract. Overall, our data showed a reduction in cells/conidia adhesion under and exposure, followed by an increase of exopolysaccharides during biofilm maturation and a variable effect on biofilm dispersal. In conclusion, extracts either inhibited or enhanced biofilm development, and this effect depended on both the microbial taxon and biofilm formation step.
两种红树植物， 和 ，的提取物在亚致死浓度下进行了分析，以研究它们对细菌、酵母和丝状真菌生物膜周期（即粘附、成熟和脱落）的潜在调节作用。还对甲醇叶提取物进行了表征，并采用 MS/MS 分析鉴定了主要化合物。在这项研究中，我们发现：（i）除了 ，所有模型的粘附都减少了 85.4%，而 则促进了高达 5.10 倍的粘附。（ii）与阴性对照相比，成熟生物膜中外多糖和蛋白质的总和和比率分别增加了 2.5 倍和 2.6 倍。此外，发现与活性氧物质的细胞内和细胞外大量产生相关的是向主要产生胞外多糖的转变。（iii）最后，通常促进了脱落。总的来说， 在较低浓度下比 提取物具有更高的生物活性。总体而言，我们的数据表明， 在 和 暴露下，细胞/分生孢子的粘附减少，随后在生物膜成熟过程中胞外多糖增加，而生物膜分散的效果则不同。总之，提取物要么抑制要么促进生物膜的形成，这种作用取决于微生物类群和生物膜形成的步骤。
