乳酸菌的分離及其產GABA發酵條件的優化

生物工程論文編號:SW137  論文字數:14436,頁數:36

目  錄
中文摘要 I
英文摘要 II
目  錄 III
1 緒論 1
1.1  乳酸菌簡介 1
1.2  γ-氨基丁酸的研究狀況 2
1.3  γ-氨基丁酸的檢測技術 6
1.4  選題意義 6
2  實驗部分 8
2.1  實驗材料 8
2.2  實驗方法 10
3  結果與分析 17
3.1  GABA檢測 17
3.2  乳酸菌分離與鑒定 21
3.3  乳酸菌發酵產GABA 23
4 討論與總結 28
5 展望 29
致謝 30
參考文獻 31

摘要：本文從市售酸奶中分離到一株產GABA的乳酸菌，經形態學和生理生化鑒定，初步確認為德氏乳桿菌。探索比色法測定GABA濃度時，發現2%的苯酚濃度、2.08%的次氯酸鈉濃度對實驗測定有利。雖然此法適用于大量樣品的檢測，但容易受到溶液中游離氨的影響，對復雜成分檢測GABA不準確。探索紙層析-分光光度法測定GABA濃度時，發現展開劑（正丁醇：冰醋酸：水）體積比為4:1:3、顯色溫度和時間分別為80℃，30min，在510nm處測定洗脫液波長時，對實驗測定有利。經過pH、溫度、接種量這3個單因素試驗及正交優化后，發現在pH6.5,溫度30℃，接種量7%時GABA產量為0.177 g/L，可以作為糙米生物轉化產GABA的初步探索。
關鍵詞：γ-氨基丁酸；德氏乳桿菌；糙米；GABA檢測

Lactic acid bacteria’s Isolation and its Optimization of GABA Fermentation Condition

Abstract：In this paper,we separated a lactic acid strain from commercial yogurt which can producing GABA.we initially identified it as L.delbrueckii through Ecology identification、Physiological and Biochemical identification。Exploring determination of GABA levels，we found that 2% concentration of phenol, 2.08% sodium hypochlorite concentration have benefit to Colorimetry。Although this method is suitable for large sample testing，it is susceptible to the impact of free ammonia in solution。Exploring determination of GABA levels，we found that the developing solvent’s(butanol: acetic acid: water) volume ratio of 4:1:3, the color temperature and time were 80℃, 30min, determining at 510nm have benefit to Chromatography—Elution。After three single-factor test s--pH, temperature 、inoculation and Orthogonal optimization，we found at pH6.5,、temperature 30 ℃、inoculum 7% ,the GABA production was 0.177 g / L。The experiment can be used as initial exploration of brown rice biotransformation of GABA.

Keywords：γ-aminobutyric acid; L.delbrueckii; Brown rice;GABA examination