Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands.
Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands.
Water Res. 2019 Jun 15;157:201-208. doi: 10.1016/j.watres.2019.03.068. Epub 2019 Mar 29.
Biofilm structure and functionality depend on extracellular polymeric substances (EPS), but analytical methods for EPS often lack specificity which limits progress of biofilm research. EPS were extracted from aerobic granular sludge and analyzed with frequently applied colorimetric methods. The colorimetric methods were evaluated based on their applicability for EPS analysis. EPS fractions of interest were proteins, sugars, uronic acids and phenolic compounds. The applied methods (Lowry method, bicinchoninic acid assay, phenol sulfuric acid method, carbazole sulfuric acid method) were investigated in terms of their sensitivity towards the selected standard compound. Interference of compounds present in EPS with the colorimetric methods was further evaluated. All methods showed to be highly depending on the choice of standard compound and susceptible towards interference by compounds present in EPS. This study shows that currently used colorimetric methods are not capable of accurately characterizing EPS. More advanced methods are needed to be able to draw conclusions about biofilm composition, structure and functionality.
生物膜的结构和功能取决于细胞外聚合物质（EPS），但 EPS 的分析方法通常缺乏特异性，限制了生物膜研究的进展。从好氧颗粒污泥中提取 EPS，并采用常用的比色法进行分析。基于比色法在 EPS 分析中的适用性，对其进行了评估。感兴趣的 EPS 分数是蛋白质、糖、糖醛酸和酚类化合物。应用的方法（Lowry 法、双缩脲法、苯酚硫酸法、咔唑硫酸法）根据其对所选标准化合物的敏感性进行了研究。还进一步评估了 EPS 中存在的化合物对比色法的干扰。所有方法都高度依赖于标准化合物的选择，并且容易受到 EPS 中存在的化合物的干扰。本研究表明，目前使用的比色法不能准确地表征 EPS。需要更先进的方法来能够得出关于生物膜组成、结构和功能的结论。
