开放条件下烟管菌XX-2对孔雀石绿染料的高效降解

Efficient degradation of Malachite Green dye by Bjerkandera adusta XX-2 strain in an air-opening system

摘要:

【目的】评价白腐真菌Bjerkandera adusta XX-2处理孔雀石绿染料废水的能力, 为其在染料废水中的应用提供参考依据。【方法】采用批次实验在开放条件下研究通气、pH、温度、染料初始浓度、培养时间、碳源、氮源、金属离子、盐度等因子对该菌降解孔雀石绿的影响。同时利用植物萌发、微生物抑菌和水生动物致死实验对降解产物进行毒性测试。【结果】B. adusta XX-2菌株在开放的非灭菌条件下也能高效降解孔雀石绿。例如, 在初始浓度为120 mg/L且以孔雀石绿为唯一营养源的条件下降解率也能达到60%。静置培养和摇动培养呈现出几乎相同的降解率, 这可以为技术应用节约动力成本。最适降解pH与温度分别为7.0和25 °C。在上述参数体系的优化基础上, 分别进行了碳源、氮源与金属离子的添加优化实验, 结果显示低浓度的碳源(如柠檬酸钠)、氮源(如氯化铵)和金属离子(如Zn2+)均可大大提高B. adusta XX-2对孔雀石绿的脱色效率。同时B. adusta XX-2的降解也能在很高的盐浓度下进行。毒性测试表明降解后的染料对植物、微生物、水生生物的毒性大大减少。【结论】B. adusta XX-2菌株在处理染料废水方面具有很大的应用潜力。

Abstract:

[objective] Our aim was to evaluate the ability of Bjerkandera adusta XX-2 strain in degrading Malachite Green (MG) dye in order to provide reference for its application in treating dye wastewater. [Methods] Batch experiment was carried out to decolorize MG dye in an air-opening system in this study. Experimental parameters, such as oxygen demand, initial pH value, temperature, initial dye concentration, incubation time, carbon source, nitrogen source, metal ion and salinity, was investigated to analyze their effect on the decolorization of MG. The toxicity test of decolorized products on plant, aquatic animal and microorganism was also carried out in this study. [Results] B. adusta XX-2 strain showed efficient decolorization of MG dye without supplying basic salt medium in non-sterile culture, for example, decolorization rate still reached above 60% at the initial dye concentration of 120 mg/L, using MG as sole nutrient source. Static culture presented the similar MG decolorization rate as shaken culture, indicative of low-cost application potential for B. adusta XX-2 strain. The optimal pH and temperature for decolorization were 7.0 and 25 °C, respectively. Based on the system with optimal parameters, carbon source, nitrogen source and metal ion were separately added for choosing appropriate dosage. The results indicated that carbon source (e.g. sodium citrate), nitrogen source (e.g. ammonium chloride) and metal ion (e.g. Zn2+), even at a low concentration, all could greatly improve the efficiency of decolorization. Moreover, B. adusta XX-2 could decolorize MG in dye solution with high salinity. Toxicity test showed toxicity of decolorized products on plant, aquatic animal and microorganism greatly declined, in comparison with non-decolorized MG dye. [Conclusion] B. adusta XX-2 strain had a good application potential for treating dye wastewater.