Zhu Xuanquan, Jia Meng, Zhou Weiyu, Zhou Peng, Du Yu, Yang Huanwen, Wang Ge, Bai Yuxiang, Wang Na
College of Tobacco Science, Yunnan Agricultural University, Kunming 650201, China.
College of Tobacco Science, Yunnan Agricultural University, Kunming 650201, China.
Environ Int. 2025 Jul;201:109550. doi: 10.1016/j.envint.2025.109550. Epub 2025 May 22.
Nicotine, a potential environmental pollutant that has raised increasing concerns, accumulates to significant levels in soils under long-term tobacco monoculture, posing substantial risks to both local ecosystems and human health. Addressing this challenge, the screening and utilization of nicotine-degrading bacteria have emerged as a central remediation strategy. In this study, we isolated nicotine-degrading bacteria from tobacco-cultivated soils and subsequently immobilized them onto biochar to optimize degradation efficiency. A systematic investigation was conducted to examine the synergistic effects and underlying degradation mechanisms of the biochar-bacteria complex. Notably, we successfully isolated Paenarthrobacter ureafaciens N21 (N21), a bacterial strain capable of degrading nicotine through the pyridine pathway. When immobilized on biochar (BN21), the composite maintained robust degradation capabilities in both culture media and soil environments. Compared with free N21, BN21 demonstrated a 1.4 times enhancement in nicotine degradation efficiency and significantly improved colonization capacity by the degrading bacteria (P < 0.0001). Stability assessment tests further confirmed BN21's consistent degradation performance under diverse environmental conditions. Integrated microbiomic and metabolomic analyses revealed that BN21 induced significant alterations in soil microbial community structure and metabolic profiles, while enhancing the soil's resistance to repeated nicotine disturbances. Importantly, BN21 facilitated synergistic interactions between nicotine-degrading bacteria and indigenous microorganisms, collectively mediating nicotine decomposition through coordinated pyridine and pyrrolidine pathways. The novel discovery of bacteria-loaded biochar synergistically enhancing nicotine removal highlights the potential of biochar-microbe composites for targeted pollutant elimination. This approach shows promising prospects for future applications in ecological remediation of various organic contaminants, providing innovative perspectives for developing microbiome-based green remediation strategies.
尼古丁是一种潜在的环境污染物，日益引起人们的关注，在长期烟草单作的土壤中会累积到显著水平，对当地生态系统和人类健康都构成重大风险。为应对这一挑战，筛选和利用尼古丁降解细菌已成为一种核心修复策略。在本研究中，我们从种植烟草的土壤中分离出尼古丁降解细菌，随后将它们固定在生物炭上以优化降解效率。我们进行了系统研究，以考察生物炭 - 细菌复合物的协同效应及潜在降解机制。值得注意的是，我们成功分离出了脲芽孢八叠球菌N21（N21），这是一种能够通过吡啶途径降解尼古丁的细菌菌株。当固定在生物炭上（BN21）时，该复合物在培养基和土壤环境中均保持强大的降解能力。与游离的N21相比，BN21的尼古丁降解效率提高了1.4倍，且降解细菌的定殖能力显著提高（P < 0.0001）。稳定性评估测试进一步证实了BN21在不同环境条件下的降解性能一致。综合微生物组学和代谢组学分析表明，BN21引起了土壤微生物群落结构和代谢谱的显著变化，同时增强了土壤对反复尼古丁干扰的抗性。重要的是，BN21促进了尼古丁降解细菌与本土微生物之间的协同相互作用，共同通过协调的吡啶和吡咯烷途径介导尼古丁分解。载菌生物炭协同增强尼古丁去除的新发现突出了生物炭 - 微生物复合物在靶向去除污染物方面的潜力。这种方法在未来各种有机污染物的生态修复应用中显示出广阔前景，为开发基于微生物组的绿色修复策略提供了创新视角。
