Laboratory of Environmental Biotechnology, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, CZ-14220 Prague 4, Czech Republic.
Institute for Environmental Studies, Faculty of Science, Charles University, Benátská 2, CZ-12801 Prague 2, Czech Republic.
Molecules. 2020 Jan 18;25(2):400. doi: 10.3390/molecules25020400.
Chlorhexidine (CHX) and octenidine (OCT), antimicrobial compounds used in oral care products (toothpastes and mouthwashes), were recently revealed to interfere with human sex hormone receptor pathways. Experiments employing model organisms-white-rot fungi and -were carried out in order to investigate the biodegradability of these endocrine-disrupting compounds and the capability of the fungi and their extracellular enzyme apparatuses to biodegrade CHX and OCT. Up to 70% ± 6% of CHX was eliminated in comparison with a heat-killed control after 21 days of in vivo incubation. An additional in vitro experiment confirmed manganese-dependent peroxidase and laccase are partially responsible for the removal of CHX. Up to 48% ± 7% of OCT was removed in the same in vivo experiment, but the strong sorption of OCT on fungal biomass prevented a clear evaluation of the involvement of the fungi or extracellular enzymes. On the other hand, metabolites indicating the enzymatic transformation of both CHX and OCT were detected and their chemical structures were proposed by means of liquid chromatography-mass spectrometry. Complete biodegradation by the ligninolytic fungi was not achieved for any of the studied analytes, which emphasizes their recalcitrant character with low possibility to be removed from the environment.
洗必泰（CHX）和奥替尼啶（OCT）是口腔护理产品（牙膏和漱口水）中使用的抗菌化合物，最近被发现会干扰人体性激素受体途径。为了研究这些内分泌干扰化合物的可生物降解性以及真菌及其细胞外酶设备降解 CHX 和 OCT 的能力，进行了使用模式生物-白腐真菌和-的实验。与热灭活对照相比，在体内孵育 21 天后，CHX 的去除率高达 70%±6%。另外的体外实验证实锰依赖过氧化物酶和漆酶部分负责 CHX 的去除。在相同的体内实验中，OCT 的去除率高达 48%±7%，但 OCT 对真菌生物量的强烈吸附阻止了对真菌或细胞外酶参与的明确评估。另一方面，通过液相色谱-质谱法检测到表明 CHX 和 OCT 酶转化的代谢物，并提出了它们的化学结构。对于研究的任何分析物，木质素分解真菌都没有实现完全生物降解，这强调了它们的抗降解特性，从环境中去除的可能性很低。
