| 摘要: | Triton類非離子界面活性劑，為一混合物質，其商業產品成份中除了不同聚氧乙烯長度的聚合物外，尚同時含有直鏈與支鏈烷基酚的異構物。本研究所使用之Triton X-100為其酚基在對位位置接以支鏈辛烷基及平均9.5單位之聚氧乙烯鏈。Triton X-100可用於農藥之乳化劑、水和劑、分散劑、效果增強劑等，在農藥中其含量佔5—85%不等，故大量使用農藥，亦同時將大量的界面活性物質導入環境中；除本身具有毒性外，由於分子特殊的親水及親油基結構，一旦大量導入環境中，會改變毒性有機污染物之傳輸行為，而在環境中廣泛流佈，除嚴重影響自然生態外，對環境品質造成潛在威脅，甚至危害到人體健康。本研究取自農肥料工廠中施用農藥頻繁之溫室土壤及其溫室外排水溝底泥、中央大學附近稻田和學生宿舍排放水之樣本，以minimal salts basal（MSB）培養基含Triton X-100為唯一碳源培養，分離出至少20種可異化Triton X-100之分解菌，除了Pseudomonas putida、Pseudomonas sp.外，其他如Moraxella osloensis、Brevbacterium iodinum、Ochrobactrum anphropi、Alcaligenes eutrophus、Alcaligenes xylosoxidans、Ensifer adhaerens皆無報導具有分解Triton類界面活性劑的相關研究。菌種鑑定的方法有二，一為藉菌株利用95種不同碳源組合圖譜（BioLog®方法），二為16S rDNA序列比對。初步菌株活性分析方面，以Triton X-100為唯一碳源培養之菌體測定對Triton X-100及其推測可能之代謝產物之消耗氧氣的能力，挑選具最高耗氧活性的一株Pseudomonas sp.（82.10.6），其耗氧活性為528 mmole/min/kg of wet weight，與1994年Hideaki等人發表之Triton N-101分解菌Pseudomonas sp. strain TR01高出16.5倍，且其世代時間為1小時。本研究專注於此菌，命名為Pseudomonas sp. SH4。 riton X-100, a nonionic surfactant, was used in industrial, agricultural, and domestic applications. This surfactant belongs to octylphenol polyethoxylates and is a mixture with an average numbers of 9.5 ethoxylate units in this mixture. In this study, twenty bacterial strains were isolated from soil samples from pesticide factory (green house and ditch), ricefield nearby NCU and its ditch, drainage of dormitory at NCU, drainage of pond of NCU by using Triton X-100 as sole carbon source. They were identified by BioLog® method and 16S rDNA sequences. Among them, except of Pseudomonas putida and Pseudomonas sp., Moraxella osloensis, Brevbacterium iodinum, Ochrobactrum anphropi, Alcaligenes eutrophus, Alcaligenes xylosoxidans and Ensifer adhaerens have not been reported to be capable in the degradation of Triton X-100. Brevbacterium iodinum was the only Gram-positive bacterium isolated in this study. Oxygen uptake activity by bacteria grown from MSB containing 0.5% Triton X-100 demonstrated that Pseudomonas sp. (82.10.6), name as Pseudomonas sp. SH4, showed the highest activity, specific activity was 528 mmole/min/kg of wet weight, and was 16.5 fold than Pseudomonas sp. strain TR01 which was reported in 1994 to degradation of Triton N-101 by Hideaki et al. |
