固定化乳白耙齿菌脱色茜素红的研究

利用海藻酸钙法对乳白耙齿菌进行固定化,检测固定化乳白耙齿菌（固定化菌）对几种染料的脱色能力。同时,考察pH值、染料浓度、金属离子、碳源种类、氮源种类、盐浓度对固定化菌脱色茜素红的影响。结果表明,固定化菌的优化条件为海藻酸钠3%、氯化钙5%、固定化时间6h、接菌量10g/100mL;固定化菌对6种染料均可脱色,其中对茜素红染料的脱色效果最为明显;固定化菌对茜素红的脱色率随染料浓度的增加而下降,当染料浓度高于250mg/L时,其脱色效果明显下降;固定化菌对茜素红脱色的适宜pH为7,适宜碳源为可溶性淀粉、适宜氮源为硝酸铵。另外,固定化菌对茜素红的脱色率随盐浓度的升高,呈下降趋势,当盐浓度高于3%时,脱色率下降明显;固定化菌于生理盐水中保存10d后,脱色率维持在较高水平,达94.20%;固定化菌重复利用5次后,脱色率仍高达88.70%。

Decolorization of alizarin red by immobilized Irpex lacteus

The decolorization ability of sodium alginate immobilized Irpex lacteus was optimized under different levels of pH, dye concentration, metal ions, carbon source, nitrogen source, and salt concentration. The results showed that the optimized conditions of immobilized I. lacteus were: application of 3% alginate and 5% calcium chloride, immobilization period of 6h, and inoculation amount of 10g/100mL. All six dyes tested could be decolorized by immobilized I. lacteus, but decolorization of alizarin red dye was particularly obvious. Decolorization rate decreased with the increase of dye concentration, and significantly declined when dye concentration >250mg/L. The optimum pH was 7, and the suitable carbon and nitrogen sources were soluble starch and ammonium nitrate respectively. Decolorization rate of alizarin red tended to decline with the increase of salt concentration, and significantly declined when salt concentration >3%. The decolorization rate could be maintained at a relatively high level of 94.20% after being kept in physiological saline for 10 days, and it was still maintained at 88.70% after immobilized I. lacteus was recycled for 5 times.