多环芳烃蒽在两种贝类中的检测及生物降解研究

Study on the detection and biodegradation of polycyclic aromatic hydrocarbon anthracene in 2 kinds of shellfishs

中文关键词:  贝类  蒽  生物降解  混菌  降解条件

英文关键词:shellfish  anthracene  biodegradation  bacteria mixture  degradation conditions

中文摘要:

      目的 比较月亮贝(Neolamprologus calliurus)和竹蛏(Solen strictu)对多环芳烃蒽的富集作用, 筛选获得高效蒽降解菌株。方法 采用气相色谱-质谱法(gas chromatohraphy-mass spectromety, GC-MS)检测两种贝类中蒽的含量, 采用高效液相色谱法(high performance liquid chromatography, HPLC)比较6种菌株和上述菌株等体积混合得到的菌群对蒽的降解率, 并对高效菌株或菌群的降解条件进行优化。结果 两种贝类均能够对蒽进行富集, 在0.5和5 μg/L蒽处理条件下, 月亮贝对蒽的富集比竹蛏高2.75和3.34倍。6种菌株对蒽的降解率可达92.11%~95.90%, 而混合菌群对蒽的降解率最高可达97.17%。菌群生物降解蒽的最佳条件为pH 6、温度27 ℃、降解时间15 d。另外, 添加30 mg/L Mg2+促进了混合菌群对蒽的降解。结论 月亮贝对蒽的富集高于竹蛏, 混合菌群对蒽的降解率最高, 添加Mg2+可以促进蒽的生物降解。

英文摘要:

      Objective To compare the enrichment degree of polycyclic aromatic hydrocarbon anthracene in moon shells (Neolamprologus calliurus) and razor clams (Solen strictu) under different concentrations, and screen the most efficient anthracene-degrading bacterial strains. Methods The content of anthracene in the 2 kinds of shellfishs were determinated by gas chromatography-mass spectrometry (GC-MS), the degradation efficiencies of anthracene between the 6 kinds of strains and the bacterial mixture obtained from an equal volume mixture of the above 6 kinds of strains were compared by high performance liquid chromatography (HPLC), and the degradation conditions of the most effective strain or the strains mixture were optimized. Results Both of 2 kinds of shellfishs could enrich anthracene, and the enrichment of anthracene by moon shells was 2.75 and 3.34 times higher than that of razor clams under the conditions of 0.5 and 5 μg/L anthracene treatment. The degradation rates of anthracene by the 6 kinds of strains ranged from 92.11% to 95.90%, and the highest degradation efficiency of 97.17% was achieved by the strains mixture. The optimum conditions for the biodegradation of anthracene were pH 6, temperature 27 ℃ and degradation time 5 d. In addition, the addition of 30 mg/L Mg2+ promoted the degradation of anthracene by the strains mixture. Conclusion The enrichment of anthracene by moon shells is higher than that of razor clams. The highest degradation rate of anthracene is achieved by the strains mixture, and Mg2+ could efficiently promote bio-degradation of anthracene.