2,4,6-三氯酚的共基质降解机理

Mechanism of 2,4,6-trichlorophenol degradation by means of co-substrates

分别利用经过驯化的葡萄糖降解菌和2,4,6–三氯酚(TCP)降解菌,通过添加易生物降解的有机物(葡萄糖、苯甲酸、苯酚)作为共基质,对TCP进行好氧生物降解,以考察其降解机理.当利用葡萄糖降解菌降解TCP时,在没有共基质存在时,微生物经历51 h的适应期之后,才能生长,与此同时可利用TCP作为唯一碳源而使其降解.当有共基质存在时,TCP几乎没有降解.而当利用TCP降解菌降解TCP时,在没有共基质的条件下,只需43 h的适应期可使TCP得到降解.实验结果表明:由于在没有共基质存在的条件下,葡萄糖降解菌和TCP降解菌均能利用TCP作为唯一碳源得到生长,并使TCP同时得到降解.因此在有共基质条件下,使TCP的降解效率提高的机理为次级利用,而非共代谢.

Domesticated glucose and 2, 4,6-trichlorophenol （TCP） degrading bacteria were respectively used for aerobic biodegradation of TCP by adding readily biodegradable organic matters （ glucose, benzoic acid and phenol） as co-substrates to investigate the mechanism of TCP degradation. Glucose degrading bacteria didn＇t grow until 51 hours of adaptation period in absence of co-substrates, during which TCP could be degraded by the bacteria as sole carbon source. However, TCP was little degraded in presence of co-substrates. While TCP degrading bacteria were used for aerobic biodegradation of TCP, it only took about 43 hours of adaptation period for the bacteria to remove TCP in absence of co-substrates. Experimental results indicated that both glucose and TCP degrading bacteria could utilize TCP as sole carbon source to grow,and TCP was also effectively degraded simultaneously. So TCP removal rate was accelerated in presence of co-substrates due to secondary utilization instead of co- metabolism.