Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran.
Pharmaceutical Sciences Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran.
Environ Sci Pollut Res Int. 2022 Dec;29(59):89255-89272. doi: 10.1007/s11356-022-21959-4. Epub 2022 Jul 18.
Laccase was successfully hybridized with polyamidoamine (PAMAM) dendrimer-grafted silica-coated hercynite-copper phosphate magnetic hybrid nanoflowers (MHNFs) to increase the catalytic performance of the enzyme and apply in an effective bioremoval of gemifloxacin. For this purpose, the magnetic nanoparticles (MNPs) of hercynite were covered with a silica layer, and the core-shell SiO@hercynite was then modified with PAMAM dendrimer to increase the surface area of the carrier for the enzyme attachment. Subsequently, the whole complex was hybridized with laccase and copper phosphate to attain a large surface area (104.3 m g). The fabricated MHNFs acquired the entrapment yield and efficiency of 90 ± 3% and 66 ± 5%, respectively. The catalytic activity of the fabricated biocatalyst was remained up to 50% after 13 reusability cycles. Approximately 90% of gemifloxacin was removed by the constructed MHNFs after 3 h incubation by adsorption and degradation mechanisms. The biotransformation products were then identified, and degradation pathways were proposed as defluorination, decarboxylation, elimination of a cyclopropyl group, and cleavage of the pyrrolidine moiety. Furthermore, the toxicity of gemifloxacin was effectively diminished against some bacterial strains.
漆酶成功地与聚酰胺-胺（PAMAM）树枝状大分子接枝的硅烷化硅层包裹尖晶石-磷酸铜磁杂纳米花（MHNFs）杂交，以提高酶的催化性能，并应用于有效地去除加替沙星。为此，用硅层覆盖尖晶石磁性纳米颗粒（MNPs），然后用 PAMAM 树枝状大分子修饰核壳 SiO@尖晶石，以增加载体表面面积，用于酶的附着。随后，整个复合物与漆酶和磷酸铜杂交，以获得大的表面积（104.3 m g）。所制备的 MHNFs 的包埋产率和效率分别为 90±3%和 66±5%。该制备的生物催化剂在 13 次重复使用循环后，其催化活性仍保持在 50%左右。构建的 MHNFs 在 3 h 孵育后通过吸附和降解机制可去除约 90%的加替沙星。然后鉴定了生物转化产物，并提出了脱氟、脱羧、环丙基消除和吡咯烷部分断裂的降解途径。此外，加替沙星的毒性对一些细菌菌株的有效降低。
