Department of Analytical Chemistry, Institute of Chemistry of Araraquara, UNESP, Rua Francisco Degni, 55 - Bairro Quitandinha, 14800-900 Araraquara, SP, Brazil.
Water Res. 2013 Nov 1;47(17):6596-605. doi: 10.1016/j.watres.2013.08.027. Epub 2013 Sep 6.
Nontuberculous mycobacteria are resistant to conventional water treatment; indeed, they have been recovered from a wide variety of environmental sources. Here, we applied the photoelectrocatalytic technique using a Ti/TiO2-Ag photoanode to inactivate mycobacteria. For a mycobacteria population of 5 × 10(8) CFU mL(-1), we achieved 99.9 and 99.8% inactivation of Mycobacterium kansasii and Mycobacterium avium with rate constant of 6.2 × 10(-3) and 4.2 × 10(-3) min(-1), respectively, after 240 min. We compared the proposed method with the photolytic and photocatalytic methods. Using a mycobacteria population of 7.5 × 10(4) CFU mL(-1), the proposed Ti/TiO2-Ag photoanode elicited total mycobacteria inactivation within 3 min of treatment; the presence of Ag nanoparticles in the electrode provided 1.5 larger degradation rate constant as compared with the Ti/TiO2 anode (1.75 × 10(-2) for M. kansassi and 1.98 × 10(-2) for M. avium). We monitored the degradation of the metabolites released during cellular lysis by TOC removal, sugar release, chromatography, and mass spectrometry measurements; photoelectrocatalysis and Ti/TiO2-Ag photoanodes furnished the best results.
非结核分枝杆菌能抵抗常规水处理；事实上，它们已经从各种环境来源中被回收。在这里，我们应用光电催化技术，使用 Ti/TiO2-Ag 光阳极来灭活分枝杆菌。对于 5×10(8)CFU mL(-1)的分枝杆菌种群，我们实现了 M. kansasii 和 M. avium 的 99.9%和 99.8%灭活，其速率常数分别为 6.2×10(-3)和 4.2×10(-3)min(-1)，经过 240 分钟。我们将所提出的方法与光解和光催化方法进行了比较。对于 7.5×10(4)CFU mL(-1)的分枝杆菌种群，Ti/TiO2-Ag 光阳极在 3 分钟的处理时间内引起了总分枝杆菌失活；电极中 Ag 纳米粒子的存在提供了 1.5 倍更大的降解速率常数，与 Ti/TiO2 阳极相比（M. kansassi 为 1.75×10(-2)，M. avium 为 1.98×10(-2)）。我们通过 TOC 去除、糖释放、色谱和质谱测量来监测细胞裂解过程中释放的代谢物的降解；光电催化和 Ti/TiO2-Ag 光阳极提供了最佳结果。
