Soil Science and Agricultural Chemistry, Fac. Sciences, Univ. Vigo, 32004, Ourense, Spain.
Dept. Soil Science and Agricultural Chemistry, Engineering Polytechnic School, Univ. Santiago de Compostela, 27002, Lugo, Spain.
Environ Res. 2021 Apr;195:110814. doi: 10.1016/j.envres.2021.110814. Epub 2021 Jan 30.
This work focuses on studying the efficacy of three different by-products to adsorb three antibiotics (sulfadiazine, SDZ; sulfamethazine, SMT; sulfachloropyridazine, SCP). These antibiotics can be considered pollutants of the environment when they reach water, as well as in cases where they are spread on soils through irrigation or contained in sewage sludge or livestock manure. In this study, batch-type adsorption/desorption experiments were performed for each of the three sulfonamides, adding 7 different concentrations of the antibiotics, going from 1 to 50 μmol L, and with contact time of 24 h. The results indicate that pine bark is the most efficient bioadsorbent among those studied, as it adsorbs up to 95% of the antibiotics added, while desorption is always less than 11%. However, for "oak ash" and mussel shell the adsorption is always lower than 45 and 15%, respectively, and desorption is high, reaching up to 49% from "oak ash" and up to 81% from mussel shell. Adsorption data showed good fitting to the Linear and Freundlich models, with R values between 0.98 and 1.00 in both cases. K and K adsorption parameters showed similar values for the same sorbent materials but were much higher for pine bark than for the other two bioadsorbents. The Freundlich's n parameter showed values in the range 0.81-1.28. The highest K values (and therefore the highest adsorption capacities) were obtained for the antibiotic SCP in pine bark. Pine bark showed the highest capacity to adsorb each of the antibiotics, increasing as a function of the concentration added. When the concentration of sulfonamide added was 50 μM, the amounts adsorbed were 780 μmol kg for SDZ, 890 μmol kg for SMT, and 870 μmol kg for SCP. "Oak ash" and mussel shell have low adsorption capacity for all three sulfonamides, showing values always lower than 150 μmol kg (oak ash) and 20 μmol kg (mussel shell) when a concentration of 50 μmol L of antibiotic is added. The results of this study could aid to make an appropriate management of the by-products studied, in order to facilitate their valorization and recycling in the treatment of environmental compartments polluted with sulfonamide antibiotics.
这项工作专注于研究三种不同副产物对三种抗生素（磺胺嘧啶、磺胺甲嘧啶、磺胺氯哒嗪）的吸附效果。当这些抗生素到达水或通过灌溉散布在土壤中、包含在污水污泥或牲畜粪便中时，它们可以被视为环境污染物。在这项研究中，对三种磺胺类药物中的每一种都进行了批量吸附/解吸实验，添加了 7 种不同浓度的抗生素，从 1 到 50 μmol/L，接触时间为 24 小时。结果表明，在研究的生物吸附剂中，松皮是最有效的一种，因为它可以吸附高达 95%的添加抗生素，而解吸率总是低于 11%。然而，对于“橡木灰”和贻贝壳，吸附率总是低于 45%和 15%，解吸率很高，从“橡木灰”中达到 49%，从贻贝壳中达到 81%。吸附数据对线性和 Freundlich 模型拟合良好，两种情况下的 R 值均在 0.98 到 1.00 之间。对于相同的吸附材料，K 和 K 吸附参数显示出相似的值，但对于松皮来说，这些值要比其他两种生物吸附剂高得多。Freundlich 的 n 参数显示值在 0.81-1.28 之间。在松皮中，抗生素 SCP 的 K 值（因此吸附容量）最高。松皮表现出对每种抗生素的最高吸附能力，随着添加浓度的增加而增加。当添加的磺胺类药物浓度为 50 μM 时，SDZ 的吸附量为 780 μmol/kg，SMT 为 890 μmol/kg，SCP 为 870 μmol/kg。“橡木灰”和贻贝壳对所有三种磺胺类药物的吸附能力都很低，当添加 50 μmol/L 的抗生素时，其吸附值始终低于 150 μmol/kg（橡木灰）和 20 μmol/kg（贻贝壳）。这项研究的结果可以帮助对研究中的副产物进行适当的管理，以便促进它们在处理磺胺类抗生素污染的环境组分中的增值和再循环。
