生物絮凝剂改性菌丝球负载好氧反硝化菌T13强化脱氮

Enhanced nitrogen removal by bioflocculant combined mycelial pellets loaded with aerobic denitrificans T13

由黑曲霉Y3(Aspergillus niger Y3)形成的菌丝球经过生物絮凝剂改性强化后作为生物载体固定好氧反硝化菌T13(Pseudomonas sp.T13),对其固定前后对全氮的去除效能、菌群的活性进行研究并分析固定化对于生物强化脱氮效果的影响。结果表明,菌丝球负载T13后去除全氮效能得到了明显的提高。当改性菌丝球(湿质量)与T13菌液(3.5×10^(8)CFU/ml)的质量体积比为1∶15时,去除全氮的效能最好。改性菌丝球负载T13后的表观图像和电镜扫描图像(SEM)显示,T13细菌附着在改性菌丝球的表面,且改性菌丝球载体的结构可以连续培养45 d后仍保持紧实结构。傅里叶红外光谱(FTIR)和三维荧光光谱(EEM)结果显示,胞外聚合物(EPS)在改性菌丝球固定T13的过程中起到了关键作用。菌丝球的菌丝缠绕形成的结构提供了强有力的机械结构,且具有较大的比表面积和良好的传质性能,改性菌丝球可以作为良好的生物载体用于生物强化。

After modifying and strengthening of mycelial pellets formed of Aspergillus niger Y3 by bioflocculant,the mycelial pellets were used as bio-carriers to immobilize aerobic denitrifying bacterium T13(Pseudomonas sp.T13).Removing capabilities of total nitrogen(TN)and microflora activities of mycelial pellets before and after immobilizing of Pseudomonas sp.T13 were studied,and the influence of immobilization on the denitrification effect strengthened by biological factors was analyzed.The results showed that,the removal efficiency of mycelial pellets in removing TN was effectively improved after immobilizing of Pseudomonas sp.T13.The mycelial pellets showed the best effect in TN removing when the mass-volume ratio of modified mycelial pellets(wet weight)to T13 bacterial suspension(3.5×10^(8) CFU/ml)was 1∶15.Photograph and scanning electron microscope(SEM)images of modified mycelial pellets after immobilizing of Pseudomonas sp.T13 revealed that,the T13 bacteria attached on the surface of mycelial pellets,and the structure of modified mycelial pellets maintained firm and intact after continuous cultivation for 45 days.Results of Fourier transform infrared spectroscopy(FTIR)and three-dimensional excitation-emission matrix(EEM)suggested that,extracellular polymer substances(EPS)played an important role in the process of immobilization of T13 by modified mycelial pellets.The structures formed by entangling structure of mycelial pellets provided strong mechanic structure,and had large specific surface area and fine mass transfer performance.Modified mycelial pellets can be used as good bio-carrier for biomass immobilization.