本實驗主要著重於混合菌株 ( TN-4 ) 與單一菌株 ( NTU1 ) 分別對於不同濃度正十四烷 ( Tetradecane )、不同初始酸鹼值條件下之正十四烷移除能力的研究,並探討 ( NTU1 ) 在不同基質培養下,是否會與正十四烷培養NTU1有相同的現象產生及NTU1攝取正十四烷的代謝過程。 由實驗得知當正十四烷濃度增加,TN-4與NTU1對於正十四烷的總移除量都也會隨著提高,但是在高濃度(2000ppmv、3000ppmv)正十四烷濃度下,因為受到培養基最低酸鹼值(pH4)的影響,致使NTU1、TN-4無法繼續降解正十四烷所以無法提高正十四烷之移除量。當初始酸鹼值調升時,適合微生物生長的範圍擴大,因此NTU1與TN-4 在高pH值下不受最低酸鹼值(pH4)的影響,導致2000ppmv的正十四烷100%被移除。另外也發現NTU1與TN-4之生長現象及移除正十四烷的能力極相似,證明了NTU1在TN-4中扮演著一個重要的角色。以脂肪酸類培養NTU1,發現跟正十四烷培養NTU1有類似的細胞聚集現象,因此基質並不會影響細菌的聚集現象。而由代謝物發現NTU1可能藉由雙末端氧化的方式,將正十四烷先氧化成琥珀酸(succinic acid),進而再氧化形成其他物質。
This research mainly investigated the ability of a mixed culture (TN-4) and a pure strain (NTU1) to degrade n-tetradecane under different substrate’s concentration and different medium initial acidity. Besides, this research also investigated the biodegradation of different fatty acids by utilizing NTU1 and also the analyzed of acidic organic products produced during the alkane remediation process. Experimental results indicated that increasing concentration of tetradecane increased the tetradecane biodegradation ability of NTU1 and TN-4. However, under condition of high tetradecane concentration (2000ppmv, 3000ppmv), the ability of total alkane removal was almost similar.It may be due to the rather acidic environment (pH4), inhibiting both NTU1 and TN-4’s degradation.While the initial acidity of medium was changed to a more alkaline environment, both NTU1 and TN-4 were able to attain a better growth and completely remove the alkane. In addition, it is found that NTU1 and TN-4 attain similar tendencies for their growth and alkane biodegradability, which proves that NTU1 plays a significant role among the three strains of TN-4 . Similar aggregation behavior was observed for NTU1 grown on both tetradecane and fatty acids. Thus, NTU1 perhaps degrades tetradecane via diterminal oxidation pathway, leading to the production of succinic acid, that were found in the metabolites by HPLC analysis.