曝气生物流化床中苯酚降解真菌的种群结构及分离鉴定研究

Community analysis,isolation and identification of phenol-degrading fungi in aerated biological fluidized tank

曝气生物流化床反应器（ABFT）是一种能高效处理含酚废水的生物膜反应器,处理过程中填料表面附着生长着大量丝状真菌。变性梯度凝胶电泳分析反应器填料表面生物膜种群结构,结果表明,主要丝状真菌种群为克氏地霉。利用苯酚惟一碳源培养基分离出一株具有苯酚降解能力的丝状真菌PHE-1,并进行了形态、18S rDNA序列分析和降解效率的研究。根据形态和18S rDNA序列,该菌株被鉴定为克氏地霉。苯酚降解的动力学研究表明,该菌株生长的迟滞期随初始苯酚浓度的提高而延长。在初始浓度为200~400 mg/L范围内,PHE-1降解苯酚的动力学符合底物零级动力学模型。初始苯酚浓度为400 mg/L时,苯酚对菌株生长表现出较明显的抑制作用。

Aerated biological fluidized tank （ABFT） is a kind of high-efficiency biofilm reactor for phenolic wastewater treatment, There are large amount of filamentous fungi growing on the surface of the biomass carriers. The community structure of the biofilms on the surface of biomass carriers was analyzed by denaturing gradient gel electrophoresis （ DGGE）. It was revealed that the main species of fungi belonged to Geotrichum klebahnii. A filamentous fungi strain PHE-1 that can grow on the mineral agar medium using phenol as sole carbon source was isolated, and was identified as Geotrichum klebahnii by morphology and 18S rDNA sequencing. Degradation ki- netics of phenol by PHE-1 was studied. The kinetics were zero order with respect to phenol at the initial phenol concentrations of 200- 400 mg/L. It was indicated that the lag period was extended when the initial phenol con- centration increased. Phenol of 400 mg/L exhibited significant inhibition against the growth of PHE-1.