固定化微生物对土壤中苯并芘的降解

摘要

A strain autochthonous fungus and a strain bacterium identified as Bacillus sp. and Mucor sp. They were isolated from a contaminated soil and were studied for their co-immobilization. The co-immobilization carrier and the method were investigated,which could used for screening degrade benzo[a]pyrene (BaP) in the contaminated soil efficiently. The results indicated that the degradation rates of BaP by Bacillus sp. SB02, were 33.0％ in 42 days, when the initial concentrations was 50 mg·kg-1 in soil. The degradation rates per day of BaP Mucor sp. SF06 were 69.7％ in 42 days. The degradation rate of BaP by Mucor sp. SF06 was the most rapid. The optimum immobilized carrier was modified vermiculite, and it is better mass transferred. It could degrade 95.32％ of BaP in 42 days, which was remarkably higher than the degradation rate of that by the free strains. The microstructure of immobilized mixture microorganism was observed by scanning electron microscope (SEM). Also, the process of the transmission in soil was discussed.%研究了3株细菌与3株真菌对土壤中苯并芘(BaP)的降解动态,从中筛选出l株细菌(Bacillus sp.)和l株真菌(Mucor sp.),并采用吸附法将混合菌固定在改性后蛭石上,研究了固定化混合菌对土壤中BaP的降解效果.结果表明:细菌中芽孢杆菌(Bacillus sp.,SB02)降解率最高,42 d对B[a]P的降解率为33.0%,降解速率也最快,l周可降解12.6%的BaP;真菌中毛霉(Mucor sp.,SF06)降解率最高,42 d对B[a]P的降解率为69.7%;以改性后蛭石为载体用吸附法制得的固定化混合菌,传质性能好,对BaP的降解率42d可达95.32%,高于游离菌20个百分点.