The study was designed to explore the efficiency of magnetite nanoparticles (Fe₃O₄ NPs)/bacterial cell assembly to biodegrade lignin and lignocellulose, decontaminate pulp and paper-contaminated wastewater and optimize lignin adsorption by Fe₃O₄ NPs. Water samples were collected from three paper and carton manufacturing companies, Alexandria Governorate, Egypt. Pseudomonas otitidis MCC10330, the most active and promising strain among 10 previously screened indigenous and exogenous isolates, was selected and decorated with magnetic Fe₃O₄ Nanoparticles, that were prepared by the co-precipitation method, characterized and used to decontaminate paper and pulp effluent in a batch mode bioassay for 4 h. Fe₃O₄ NPs/bacterial cell assembly achieved the highest removals (64.1, 52.0, 54.3 and 66.6%) of TSS, COD, BOD, and Total Tannin and Lignin after 1, 4 and 4 h, reaching residual concentrations (RCs) of 322, 216, 112 and 7 mg/L, which are still slightly higher (5.35, 2.7 and 1.86-fold) than their maximum permissible limits (MPLs), respectively. RCs of pH, DO and TDS in the treated effluent are accepted for safe discharging. Maximum lignin adsorption and removal (82.14%) using Fe₃O₄ NPs was achieved at the optimized conditions (pH 6, Fe₃O₄ NPs dosage of 100 mg and 10 min contact time). Results confirmed that the proposed magnetite-coated Pseudomonas otitidis treatment system is highly efficient and recommended to treat the highly contaminated pulp and paper wastewater. Also, as far as we know, this integrated assemblage is the first time to be used as a novel, very promising, eco-friendly, renewable and economical biotechnological approach to minimize/eliminate the involved pollutants with the least running time.

该研究旨在探索磁铁矿纳米粒子 (Fe ₃ O ₄ NPs)/细菌细胞组装生物降解木质素和木质纤维素、净化纸浆和纸张污染废水以及优化 Fe ₃ O ₄ NPs 对木质素吸附的效率。水样是从埃及亚历山大省的三个纸张和纸箱制造公司采集的。中耳假单胞菌MCC10330是之前筛选的10个本土和外源分离株中最活跃和最有前途的菌株，被选择并用磁性Fe ₃ O ₄纳米颗粒装饰，该纳米颗粒通过共沉淀法制备，表征并用于净化造纸和纸浆废水在批处理模式生物测定中进行 4 小时。 Fe ₃ O ₄ NP/细菌细胞组装体在 1、4 和 4 小时后对 TSS、COD、BOD 以及总单宁和木质素的去除率最高（64.1%、52.0%、54.3% 和 66.6%），残余浓度 (RCs) 达到322、216、112 和 7 mg/L，仍分别略高于其最大允许限值 (MPL)（5.35、2.7 和 1.86 倍）。处理后的废水中 pH、DO 和 TDS 的 RC 被接受，可安全排放。在优化条件（pH 6、Fe ₃ O ₄ NPs 剂量为 100 mg、接触时间为 10 分钟）下，使用 Fe ₃ O ₄ NPs 实现了最大木质素吸附和去除（82.14%）。结果证实，所提出的磁铁矿涂层耳膜假单胞菌处理系统非常有效，建议用于处理高度污染的制浆造纸废水。 此外，据我们所知，这种集成组合首次被用作一种新颖的、非常有前途的、生态友好的、可再生的和经济的生物技术方法，以在最短的运行时间内最大限度地减少/消除所涉及的污染物。