Department of Natural Sciences Teacher Education, Dong Thap University, 783 Pham Huu Lau Street, Cao Lanh City, Dong Thap Province, Postal code: 81118, Vietnam.
FEMS Microbiol Lett. 2022 Feb 12;368(21-24). doi: 10.1093/femsle/fnac001.
Thiobencarb is a herbicide globally used in the agricultural sector, and its extensive application leads to severe environmental pollution. In this study, the thiobencarb supplementation caused a significant shift in the bacterial community in the sediment slurry. An analysis of the degradation metabolites of microorganisms from the sediment indicated that deschlorothiobencarb, S-4-chlorobenzyl ethylthiocarbamate, 4-chlorobenzyl mercaptan, 4-chlorobenzyl alcohol, 4-chlorobenzoic acid and chlorobenzene were the main intermediates. The degradation rates were significantly enhanced using a horizontal-flow anaerobic reactor with immobilized cells in polyurethane foam. The degradation rates at 2.6, 12.9 and 25.6 mg L-1 concentrations by suspended microorganisms from the sediment in the mineral medium supplemented with glucose were 0.085 ± 0.000, 0.383 ± 0.010 and 0.500 ± 0.045 mg day-1, respectively. The corresponding data for degradation in the reactor were 2.54 ± 0.03, 11.69 ± 0.72 and 18.58 ± 1.83 mg day-1 at the sixth operation period. Moreover, COD removal efficiencies were >90% achieved in the reactor. The proposed method facilitates degradation using a horizontal-flow anaerobic immobilized biomass bioreactor. Moreover, this study reveals the degradation of metabolites of thiobencarb under anaerobic conditions.
硫双威是一种在农业领域中广泛使用的除草剂，其大量应用导致了严重的环境污染。在本研究中，硫双威补充剂导致沉积物泥浆中的细菌群落发生了显著变化。对沉积物中微生物降解代谢物的分析表明，去氯硫双威、S-4-氯苄基乙基硫代氨基甲酸酯、4-氯苄基硫醇、4-氯苄醇、4-氯苯甲酸和氯苯是主要的中间产物。使用填充聚氨酯泡沫的水平流厌氧固定化细胞反应器显著提高了降解速率。在补充有葡萄糖的矿物培养基中，悬浮于沉积物中的微生物对 2.6、12.9 和 25.6 mg L-1 浓度的硫双威的降解速率分别为 0.085 ± 0.000、0.383 ± 0.010 和 0.500 ± 0.045 mg day-1，而在反应器中的相应数据分别为 2.54 ± 0.03、11.69 ± 0.72 和 18.58 ± 1.83 mg day-1，在第六个运行周期。此外，在反应器中实现了>90%的 COD 去除效率。该方法促进了使用水平流厌氧固定化生物量生物反应器进行降解。此外，本研究揭示了在厌氧条件下硫双威代谢物的降解情况。
