【正文】 福州大學(xué)至誠學(xué)院 本科生畢業(yè)設(shè)計（論文） 題 目： 益生菌的篩選 姓 名： 江福萍 學(xué) 號： 211110111 系 別： 生物工程 專 業(yè)： 生物工程 年 級： 2021 級 指導(dǎo)教師： 2021 年 05 月 25 日 獨創(chuàng)性聲明 本畢業(yè)設(shè)計（論文）是我個人在導(dǎo)師指導(dǎo)下 完成 的。文中引用 他人研究成果的 部分已 在 標注 中 說明 ； 其他同志對本設(shè)計（ 論文 ）的啟發(fā)和貢獻均已在 謝辭 中 體現(xiàn)；其它內(nèi)容及成果為本人獨立 完成 。 特此聲明。 論文作者簽名： 日期： 關(guān)于論文使用授權(quán)的說明 本人完全了解福州大學(xué)至誠學(xué)院有關(guān)保留、使 用學(xué)位論文的規(guī)定，即：學(xué)院有權(quán)保留送交論文的印刷本、復(fù)印件和電子版本，允許論文被查閱和借閱；學(xué)院可以公布論文的全部或部分內(nèi)容，可以采用影印、縮印、數(shù)字化或其他復(fù)制手段保存論文。保密的論文在解密后應(yīng)遵守此規(guī)定。 論文作者簽名： 指導(dǎo)教師簽名： 日期： I 益生菌的篩選 中文摘要 益生菌是一類對宿主有益的活性微生物。它 是 定植于人體腸道、生殖系統(tǒng)內(nèi)，能改善宿主微生態(tài)平衡、發(fā)揮有益作用的活性有益微生物的總稱。動物體內(nèi)的益生菌主要有：乳酸菌、酵母菌、部分霉菌等。目 前，國內(nèi)外對各類微生物組成的復(fù)合活性益生菌產(chǎn)品比較多研究，其廣泛應(yīng)用于生物工程、食品安全、工農(nóng)業(yè)以及生命健康領(lǐng)域。 本論文從酸奶、酒、酒曲和自制酵素樣品中篩選出益生菌，以蛋白酶活力為指標，篩 出酶活高的菌株，并對其在酵素中的應(yīng)用進行初步探究。研究結(jié)果如下： （ 1）以 酸奶、酒、酒曲和自制酵素為樣品篩選益生菌，把樣品稀釋分別涂布于 MRS、PDA和孟加拉紅培養(yǎng)基上富集、分離，初步篩得 42株菌，并編號保藏。將菌株再次分離純化，結(jié)合菌落觀察和菌體顯微鏡觀察，復(fù)篩出了 18類形態(tài)特征各不相同的菌株，其中有 2類乳酸菌， 11類酵 母菌， 5類霉菌。 （ 2）將初篩得到的 42 株菌進行蛋白酶活力的測定，得 乳酸菌、酵母菌和霉菌中酶活力最高的菌株分別是 L Y14 和 M14，酶活為 、 。并將 L4 進行分子生物學(xué)和生理生化鑒定為嗜熱鏈球菌種。 （ 3）將 L Y14 參考徐祖炎的專利制作成酵素， 20 天后測得實驗組的蛋白酶活力為，對照組的蛋白酶活力為 。初步說明 L L14 可以提高酵素中的蛋白酶活力這一指標，對酵素的發(fā)酵有一定的促作進用，可以提高酵素 的功能性。 關(guān)鍵詞：益生菌，篩選，乳酸菌，酵母菌，霉菌，鑒定，酵素 II Screening of probiotics Abstract Probiotics is a kind of beneficial microanisms to its host. It is the generic terms of beneficial microanism that can produce accurate health benefits, keep microecological balance for its host, as well as other powerful functions in human intestine and reproductive system. There are several beneficial bacterias and fungis in animals: lactic acid bacteria, yeast and some moulds, etc. The most powerful products that we are studying in the world are mainly all kinds of active probiotics posed of microbials that we have mentioned above, which are widely used in biological engineering, industrial area, agricultural area, food safety and health life areas. In this essay, the enzyme of probiotics is purificated from yogurt, wine and homemade enzyme samples. With the protease activities as an index, enzymes of high quality is selected, and is applicated in enzyme preliminary exploration then. The following are the research results: （ 1） The yogurt, wine, distiller39。s yeast and homemade enzyme are took as the sample, then the sample dilution are coated on the red culture medium MRS, PDA and Bangladesh to enrich and be separated, preliminary we got 42 screening isolates, and they are numbered and preserved. After that, strain is purified again and observed with microscope. 18 kinds of morphological characteristics of different strains are screened out after a second screening. There are two kinds of lactic acid bacteria, 11 kind of yeast and five types of mold in total. （ 2） 42 strains of bacteria got in the early screening are put in the protease activity test of lactic acid bacteria. The highest enzyme activity of lactic acid bacteria, yeast and the mold of strains respectively are L4, Y14 and M14. And protease activity respectively are U/mL and U/mL and U/ mL. And L4 is identified as Streptococcus thermophilus according to the molecular biological and physiological and biochemical identification. （ 3） With the reference to Xu Zuyan’s patent, L4 and Y14 are made into enzyme. After 20 days, the protease activity of the experimental group are measured to be U/mL and protease activity to be U/mL in the control group. Preliminary it shows that L4 and L14 can improve the index of protease activity of enzyme, promote the enzyme fermentation as well as improve the functionality of the enzyme. Key words: Probiotics, Screening, Lactic acid bacteria, Yeast, Mold, Appraisal, Enzyme III 目 錄 第 1 章 緒論 ................................................................................................................................... 1 益生菌概述 ....................................................................................................................... 1 益生菌理論的產(chǎn)生 ................................................................................................. 1 益生菌的定義 ......................................................................................................... 1 益生菌作用基本機理概述 ..................................................................................... 1 益生菌的來源 ......................................................................................................... 2 益生菌的特征 ......................................................................................................... 2 益生菌的種類 ......................................................................................................... 2 益生菌的作用 ......................................................................................................... 3 益生菌的應(yīng)用 ................................................................................................................... 4 益生菌食品 ............................................................................................................. 4 益生菌保健品 ......................................................................................................... 5 益生菌存在的問題 ........................................................................................................... 5 酵素 ................................................................................................................................... 6 酵素的定義、作用及應(yīng)用 ..................................................................................... 6 評價微生物酵素的指標 ......................................................................................... 6 本課題主要研究的內(nèi)容和意義 .................