發展酵素型光學檢測系統在食品中快速檢測大腸桿菌

Development of enzyme optical detection system for the rapid detection of Escherichia coli

張岑翊(chang tsên i)

指導教授 ： 黃素華

亞洲大學/健康學院/生物科技學系碩士班/碩士(2007年)

摘要

本論文研究探討酵素型光學檢測系統應用於食品中之大腸桿菌快速檢測之可行性。食品中大腸桿菌之光學檢測系統快速偵測，是使用自行裝配建立一雛型檢測平台，結合UV 燈、選擇性濾光鏡片、光二極體感測器、光訊號轉換放大器、數位化轉換模組而成。其原理乃利用結合酵素型光學檢測系統和大腸桿菌的特異性酵素β-葡萄糖醛酸苷酵素 (β- glucuronidase，簡稱GUD) 之酵素基質，其GUD 作用於4-甲基傘形酮-β-葡萄糖醛酸苷 （4-methylumbelliferyl-β-glucuronide，簡稱MUG） 酵素基質，將其分解而產生7-hydroxy-4-methylumbelliferyl (簡稱4-MU) 的產物，產物具有於波長366 nm 之UV 光激發會產生波長449 nm 藍色螢光的特性。使用酵素型光學檢測系統偵測波長449 nm 的螢光，可知是否有GUD 的存在，藉此檢測出大腸桿菌。同時利用傳統方法，在陽性反應中分離出的大腸桿菌，藉著伊紅-甲烯藍瓊脂 (Eosin Methylene Blue Agar，簡稱EMB) 之選擇性培養基和利用三明治型的酵素連結免疫吸附方法 (sandwich Enzyme-linked immunosobent assay method，簡稱sandwich ELISA) 來確定是否為大腸桿菌。 在所測之25 株大腸桿菌及11 株非大腸桿菌中，並未發生偽陽性或偽陰性反應。以酵素型光檢測系統和傳統方法同時檢測肉品中之大腸桿菌，發現兩者結果一致，但前者僅需12 小時，而後者則需要5至7 天檢測時間。顯示此種酵素型光學檢測系統檢測技術，具有快速及自動化之優點，可以做為食品中大腸桿菌快速檢測之用。 利用本實驗發展的酵素型光學檢測系統來偵測食品中之大腸桿菌，可避免人為主觀上的誤差和縮短檢測的時間，因此可快速且準確的檢測出大腸桿菌，提供食品安全更好的保障。

關鍵字

大腸桿菌 ； ，β-葡萄糖酸甘酵素，4-甲基傘形酮-β-葡萄糖醛酸苷

並列摘要

The aim of this study was to investigate whether the feasibility ofenzyme optical detection system could rapidly examine the Escherichia coli (E. coli) in food. The prototyping detection platform was built by integration of silicon photodiode, optic selective filter, photocurrent amplifier and digitize device. We make use of the β-glucuronidase (GUD) of particularity enzyme of E. coli, meeting will 4-methylumbelliferyl-β-glucuronide (MUG) resolve, producing 7-hydroxy-4- methylumbelliferyl outcome, and its outcome make use of the wave-length 366 nm to stir up the blue fluorescence that will produce the wave-length 449 nm. The production of blue fluorescence in the enzyme optical detection system was induced by the reaction between GUD of the E. coli and MUG. We can know GUD existence that the enzyme optical detection system detects the wave-length 449 nm the fluorescence, by this existence which examines E. coli. Furthermore, we used of Eosin Methylene Blue Agar (EMB) media and the sandwich ELISA method again to authenticate the E. coli that we separate.
Detection of E. coli in the diet meat results in both enzyme optical detection system and traditional methods. However, detection with enzyme optical detection system takes only 12 hours while the traditional method needs 5 to 7 days. It’s no doubt that the enzyme optical detection system is provided with advantage of the efficiency and automation then that can be a traditional standard method used in detecting E. coli in food.
Develop enzyme optical detection system to detect, can avoid an artificial subjective and last error margin and shorten time of examination, so fast and examine E. coli accurately, provide the food the safe and better guarantee.

並列關鍵字

E. coli ； β-glucuronidase ； 4-methylumbelliferyl-β-glucuronide

參考文獻

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