苯酚高效降解菌的筛选鉴定及其降酚特性研究

将焦化厂排水沟污泥中的细菌,通过以苯酚为惟一碳源的培养基逐步驯化,筛选苯酚降解菌株;通过形态观察、生理生化试验、16SrDNA序列分析对其进行初步鉴定,利用4-氨基安替比林分光光度法测定菌株在不同温度、pH、接种量及最适条件下的降酚能力.结果表明:筛选获得1株耐酚能力达2 200mg/L的苯酚高效降解菌株JDM-2-1,初步鉴定其为球形芽孢杆菌(B.sphaericus).菌株JDM-2-1降酚的最佳温度为35℃,最佳pH值为5.0,降酚能力与接种量成正相关.在最适条件下,当接种量为2%时,菌株JDM-2-1能在42h内将800mg/L的苯酚完全降解,且对浓度为1 600mg/L的苯酚有一定的降解能力.

Screening,identification and degrading characteristics of a high phenol-degrading bacterial strain

In order to screen high phenol-degrading bacterial strains,bacteria in the sludge of a coking plant was acclimated successively by the inorganic salt medium containing phenol as a sole carbon source.Phenol-degrading bacterial strain was identified preliminarily by its morphological,physiological and biochemical characteristics,and 16S rDNA sequences.The phenol degradation ability under different temperature,pH,inoculation amount,and optimal condition was determined by 4-AAP spectrophotometric method.The results showed that the strain JDM-2-1 could tolerate phenol of 2 200 mg/L,and it was identified as Bacillus sphaericus.The optimal temperature of phenol degradation was 35 ℃,and the optimal pH value was 5.0.The phenol degradation ability of JDM-2-1 was correlated positively to inoculatin amount.Under optimal conditions,it could completely degrade phenol of 800 mg/L in 42 h when inoculation amount was 2%,and it could degrade phenol of 1 600 mg/L partly as well.The results indicated that the JDM-2-1 was a adaptable,high phenol-degrading bacterial strain.