二仁溪底泥微生物對商品化多氯聯苯Aroclors之脫氯作用

Reductive Dechlorination of Aroclors by Anaerobic Microorganisms from Erh-Jen River Sediments

採集台南市灣裡地區二仁溪下游經多氯聯苯污染底泥之微生物，經由不同商品化多氯聯苯--Aroclor 1242、Aroclor 1254、Aroclor 1260之馴化增殖培養兩個月後，取得馴化菌液，分別針對三種Aroclors進行脫氯測試。實驗結果顯示，馴化混合菌可將三種商品化多氯聯苯混合物之部分多氯聯苯分子上的氯取代基移除，其對於各Aroclors之間位（ortho-position）和對位（para-position）氯基的脫氯量分別為7.11%、7.72%、11.94%。此外，採用多氯聯苯單品馴化培養之混合菌液進行Aroclors脫氯實驗，其中以345-三氯聯苯馴化混合菌對Aroclor 1242的脫氯量最高，達到15.23%，然而其脫氯形態與其它多氯聯苯單品馴化混合菌所進行的並無明顯不同，至於以35-二氯聯苯、234-三氯聯苯、245-三氯聯苯或246-三氯聯苯馴化的厭氧混合菌，其脫氯作用並無明顯提升。

Anaerobic microorganisms collected from polychlorinated biphenyls （PCBs）-contaminated sediments in Erh-Jen River located in Tainan City were acclimated and enriched separately by Aroclor 1242, Aroclor 1254 and Aroclor 1260 for 2 months. The dechlorination results showed that the Aroclor-acclimated mixed cultures could remove chloride from some PCB molecules. And the chloride removal ratio for 1242, 1254 and 1260 were 7.11%, 7.72%, and 11.94%, respectively. In addition, mixed cultures acclimated by a single PCB congener, 345-trichlorobiphenyl （345-CBp）, dechlorinated Aroclors in a ratio up to 15.23%, much higher than the Aroclor-acclimated cultures did. However, the microbial dechlorination was not accelerated by the acclimation of 35-CBp, 234-CBp, 245-CBp and 246-CBp. All PCB congener-acclimated mixed cultures performed the Aroclordechlorination in a similar pattern.