优势黄杆菌对蒽、菲、芘混合物的降解特征研究

为探索混合多环芳烃的生物降解特征，利用两株优势黄杆菌，对混合蒽、菲、芘进行了降解研究．高效液相色谱分析表明，混合多环芳烃的降解56．3％～69．6％在前10h内完成，其生物降解进程和单基质相似，但降解效率低于单基质．混合体系中蒽、菲、芘在不同菌株作用下有按特定优先顺序降解的特征，但两株黄杆菌(FCN1和FCN2)的混合菌并不促进混合多环芳烃的降解．降解130h后，体系中蒽、菲、芘消除，但总有机碳去除率仅达到60．1％～72．7％，说明部分多环芳烃转化为中间代谢产物．菌数测定表明，FCN1和FCN2利用多环芳烃及其降解中间产物繁殖生长，菌数最高时分别增长200倍和100倍，但菌数增长滞后于多环芳烃的浓度变化．研究表明，混合多环芳烃之间具有降解竞争抑制特征，且其生物降解具有规律性．

Study to Degradation Characters of Preponderant Flavobacterials Strains in a Mixture of Anthracene, Phenanthrene and Pyrene

The bio-degradation characters of mixed polycyclic aromatic hydrocarbons (PAHs), containing anthracene, phenanthrene and pyrene, by employing two preponderant flavobacteria (FCN1 and FCN2) for degradation, were studied. The results analyzed by high performance liquid chromatograph showed that 56.3%-69.6% degradation of mixed substrates (PAHs) occurred during the first 10 hours of degradation, the degradating courses of them were similar to the sole-substrates, but the degradating ratio of mixed substrates was lower than that of sole-substrates. It is found that the 3 PAHs in mixture are degradated in a specified order by the two different strains, but FCN1 and FCN2 cannot collaboratively promote the degradation. The PAHs in the mixture system disappeared after incubation for 130 h, however, the total organic carbon degradating ratio was only 60.1%-72.7%, and it suggested that part of the PAHs was degradated into intermediary metabolites. The number of FCN1 and FCN2 has increased to be 200 and 100 times respectively, revealing their assimilation to mixed PAHs, but the increase has lagged behind the descent periods of the PAHs. Degradation of PAHs in mixture is characterized by competitive inhibition, and some rules could be found in the degradation process.