Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, 51000 Rijeka, Croatia.
Bioinstitut d.o.o., R. Steinera 7, 40000 Čakovec, Croatia.
Int J Mol Sci. 2021 Aug 23;22(16):9095. doi: 10.3390/ijms22169095.
The bacterium is still one of the probable causes of waterborne diseases, causing serious respiratory illnesses. In the aquatic systems, exists inside free-living amoebae or can form biofilms. Currently developed disinfection methods are not sufficient for complete eradication of biofilms in water systems of interest. Photodynamic inactivation (PDI) is a method that results in an antimicrobial effect by using a combination of light and a photosensitizer (PS). In this work, the effect of PDI in waters of natural origin and of different hardness, as a treatment against biofilm, was investigated. Three cationic tripyridylporphyrins, which were previously described as efficient agents against alone, were used as PSs. We studied how differences in water hardness affect the PSs' stability, the production of singlet oxygen, and the PDI activity on adhesion and biofilm formation and in biofilm destruction. Amphiphilic porphyrin showed a stronger tendency for aggregation in hard and soft water, but its production of singlet oxygen was higher in comparison to tri- and tetracationic hydrophilic porphyrins that were stable in all water samples. All three studied porphyrins were shown to be effective as PDI agents against the adhesion of the to polystyrene, against biofilm formation, and in the destruction of the formed biofilm, in their micromolar concentrations. However, a higher number of dissolved ions, i.e., water hardness, generally reduced somewhat the PDI activity of all the porphyrins at all tested biofilm growth stages.
这种细菌仍然是水源性疾病的可能原因之一，会导致严重的呼吸道疾病。在水生系统中，它存在于自由生活的变形虫内或可以形成生物膜。目前开发的消毒方法不足以完全消除感兴趣的水系统中的生物膜。光动力失活（PDI）是一种通过光和光敏剂（PS）的组合产生抗菌效果的方法。在这项工作中，研究了 PDI 在天然来源和不同硬度的水中作为生物膜处理的效果。三种阳离子三吡啶卟啉，之前被描述为单独对抗的有效剂，被用作 PS。我们研究了水硬度的差异如何影响 PS 的稳定性、单线态氧的产生以及 PDI 对 黏附、生物膜形成和生物膜破坏的活性。两亲卟啉在硬水和软水中有更强的聚集趋势，但与在所有水样中稳定的三价和四价亲水性卟啉相比，其单线态氧的产生更高。研究的三种卟啉都被证明在微摩尔浓度下是有效的 PDI 试剂，可对抗 的黏附到聚苯乙烯上，可抑制生物膜的形成，并可破坏已形成的生物膜。然而，更多的溶解离子，即水硬度，通常会在所有测试的生物膜生长阶段略微降低所有卟啉的 PDI 活性。
