Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67132, Xanthi, Greece.
Laboratory of Plant and Environmental Biotechnology, Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, 41500, Larissa, Greece.
Environ Sci Pollut Res Int. 2021 Jan;28(4):3774-3786. doi: 10.1007/s11356-020-09231-z. Epub 2020 May 16.
The large quantities and the persistent nature of fungicide wastewaters have increased the efforts towards a sustainable technological solution. In this context, fludioxonil-contaminated wastewater was treated in an upflow immobilized cell bioreactor, resulting in chemical oxygen demand (COD) removal efficiency even higher than 80%, whereas the electrical conductivity (EC) of the effluent was gradually increased. Organic-F was mineralized by 94.0 ± 5.2%, which was in accordance with the high fludioxonil removal efficiency (95.4 ± 4.0%). In addition, effluent total Kjeldahl nitrogen (TKN) concentration reduced significantly during bioprocessing. A strong relationship among COD removal, TKN/total nitrogen removal, and effluent EC increase (p < 0.01) was identified. Despite the adequate aeration provided, effluent nitrite and nitrate concentrations were negligible. Illumina sequencing revealed a reduction in the relative abundances of Betaproteobacteria, Chloroflexi, Planctomycetes, and Firmicutes and an increase in the proportion of Alphaproteobacteria and Actinobacteria. A shift in bacterial communities occurred during fludioxonil treatment, resulting in the significant increase of the relative abundances of Empedobacter, Sphingopyxis, and Rhodopseudomonas (from 0.67 ± 0.13% at the start-up to 34.34 ± 1.60% at the end of biotreatment). In conclusion, the immobilized cell bioreactor permitted the proliferation of specialized activated sludge microbiota with an active role in the depuration of postharvest fungicides.
大量且持久的杀菌剂废水增加了对可持续技术解决方案的努力。在这种情况下，用过的氟唑菌酰胺废水在上升流固定细胞生物反应器中进行处理，即使化学需氧量（COD）去除效率高于 80%，废水的电导率（EC）也逐渐增加。有机-F 的矿化率达到 94.0±5.2%，与氟唑菌酰胺的高去除效率（95.4±4.0%）相符。此外，生物处理过程中废水总凯氏氮（TKN）浓度显著降低。COD 去除、TKN/总氮去除和废水 EC 增加之间存在很强的关系（p<0.01）。尽管提供了充足的曝气，但废水中的亚硝酸盐和硝酸盐浓度可以忽略不计。Illumina 测序显示，Betaproteobacteria、Chloroflexi、Planctomycetes 和 Firmicutes 的相对丰度降低，而 Alphaproteobacteria 和 Actinobacteria 的比例增加。在氟唑菌酰胺处理过程中，细菌群落发生了变化，导致 Empedobacter、Sphingopyxis 和 Rhodopseudomonas 的相对丰度显著增加（从启动时的 0.67±0.13%增加到生物处理结束时的 34.34±1.60%）。总之，固定细胞生物反应器允许专门的活性污泥微生物群增殖，在清除采后杀菌剂方面发挥积极作用。
