Jonović Marko, Jugović Branimir, Žuža Milena, Đorđević Verica, Milašinović Nikola, Bugarski Branko, Knežević-Jugović Zorica
Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, 11000 Belgrade, Serbia.
Institute of Technical Science of the Serbian Academy of Sciences and Arts (SASA), Knez Mihailova 35/IV, 11000 Belgrade, Serbia.
Polymers (Basel). 2022 Jun 28;14(13):2614. doi: 10.3390/polym14132614.
The aim of this study was to investigate covalent immobilization of horseradish peroxidase (HRP) on magnetic nanoparticles (Mag) encapsulated in calcium alginate beads (MABs) for color degradation, combining easy and fast removal of biocatalyst from the reaction mixture due to its magnetic properties and strong binding due to surface alginate functional groups. MABs obtained by extrusion techniques were analyzed by optical microscopy, FEG-SEM and characterized regarding mechanical properties, magnetization and HRP binding. HRP with initial concentration of 10 mg/g was successfully covalently bonded on MABs (diameter ~1 mm, magnetite/alginate ratio 1:4), with protein loading of 8.9 mg/g, immobilization yield 96.9% and activity 32.8 U/g. Immobilized HRP on MABs (HRP-MABs) was then used to catalyze degradation of two anthraquinonic dyes, Acid Blue 225 (AB225) and Acid Violet 109 (AV109), as models for wastewater pollutants. HRP-MABs decolorized 77.3% and 76.1% of AV109 and AB225, respectively after 15 min under optimal conditions (0.097 mM HO, 200 mg of HRP-MABs (8.9 mg/g), 0.08 and 0.1 g/mg beads/dye ratio for AV109 and AB225, respectively). Biocatalyst was used for 7 repeated cycles retaining 75% and 51% of initial activity for AB225 and AV109, respectively, showing potential for use in large scale applications for colored wastewater treatment.
本研究的目的是研究辣根过氧化物酶（HRP）共价固定在包裹于海藻酸钙珠（MABs）中的磁性纳米颗粒（Mag）上以进行颜色降解，结合因其磁性特性而易于快速从反应混合物中去除生物催化剂以及由于表面海藻酸官能团而具有的强结合力。通过挤压技术获得的MABs通过光学显微镜、场发射扫描电子显微镜进行分析，并对其机械性能、磁化强度和HRP结合进行表征。初始浓度为10 mg/g的HRP成功共价结合在MABs上（直径约1 mm，磁铁矿/海藻酸盐比例为1:4），蛋白质负载量为8.9 mg/g，固定化产率为96.9%，活性为32.8 U/g。然后，固定在MABs上的HRP（HRP-MABs）用于催化两种蒽醌染料酸性蓝225（AB225）和酸性紫109（AV109）的降解，作为废水污染物的模型。在最佳条件下（0.097 mM H₂O₂，200 mg HRP-MABs（8.9 mg/g），AV109和AB225的珠/染料比例分别为0.08和0.1 g/mg），15分钟后HRP-MABs分别使AV109和AB225脱色77.3%和76.1%。生物催化剂用于7个重复循环，AB225和AV109分别保留初始活性的75%和51%，显示出在大规模处理有色废水应用中的潜力。
