發(fā)布時(shí)間：2018-05-06 13:31

  本文選題：益生菌 + 益生特性��； 參考：《東北農(nóng)業(yè)大學(xué)》2012年碩士論文

【摘要】：嗜酸乳桿菌和雙歧桿菌是人體腸道重要的益生菌群,其在腸道內(nèi)的數(shù)目是評(píng)價(jià)機(jī)體健康程度的重要指標(biāo),它們具備多種保健功能,如酸和膽汁鹽耐受性,粘附人體上皮細(xì)胞,定植腸道產(chǎn)生細(xì)菌素,改善乳糖不耐癥,降低膽固醇、氨和其他毒性物質(zhì),產(chǎn)生B族維生素,使遭受抗生素破壞的紊亂腸道菌群恢復(fù)正常,刺激免疫反應(yīng)等。目前我國(guó)益生菌產(chǎn)品面臨的關(guān)鍵問題是工業(yè)、胃腸道脅迫對(duì)菌株的各種破壞,如產(chǎn)品的制造、貯存、銷售、食用過程。雙歧桿菌、嗜酸乳桿菌等益生菌,多為厭氧菌或兼性厭氧菌,生長(zhǎng)過程中不形成芽孢,抗性較差,生命活動(dòng)中還會(huì)產(chǎn)生一些危機(jī)自身繁殖的乳酸和乙酸等代謝物,故在液體條件下難以長(zhǎng)期保存；另外益生菌產(chǎn)品的貯存和運(yùn)輸均要求冷鏈,貨架期較短。本課題針對(duì)以上各種弊端,研究將益生菌以干物質(zhì)狀態(tài)應(yīng)用,實(shí)現(xiàn)益生菌的隨時(shí)膳食補(bǔ)充。 本研究首先利用細(xì)菌生態(tài)學(xué)、生理學(xué)和16S rDNA基因序列分析,篩選出性能較佳的5株益生菌作為研究對(duì)象,研究其益生特性；其次優(yōu)化設(shè)計(jì)確定5株益生菌的最佳凍干保護(hù)劑組合,研究每株益生菌菌粉的保存穩(wěn)定性；再次對(duì)5株益生菌進(jìn)行小中試發(fā)酵,從pH、滴定酸度、質(zhì)構(gòu)物性和流變學(xué)特性來分析比較5種發(fā)酵乳,以及利用HPLC進(jìn)行主體代謝產(chǎn)物的含量測(cè)定；最后確定吸管和瓶蓋的應(yīng)用方式。 益生特性試驗(yàn)表明：嗜酸乳桿菌和動(dòng)物雙歧桿菌都有很好的酸和膽汁鹽耐受性,動(dòng)物雙歧桿菌的耐酸性較強(qiáng)于嗜酸乳桿菌的；5株益生菌對(duì)致病菌大腸桿菌、沙門氏菌和金黃色葡萄球菌均有抑制作用,嗜酸乳桿菌的抑菌性較強(qiáng)于動(dòng)物雙歧桿菌的；五株益生菌均不具有耐藥性,對(duì)抗生素青霉素、鏈霉素和乙酰螺旋霉素均敏感。保存穩(wěn)定性試驗(yàn)表明：在凍干保護(hù)劑脫脂乳、蔗糖、海藻糖和Vc鈉鹽的最佳組合下,5株益生菌的凍干存活率均在85.00%以上,5株益生菌菌粉在4℃和25℃下保存12個(gè)月,菌粉活菌數(shù)都在1.0×108cfu/g以上,達(dá)到了FAO/WHO建議食品益生菌活菌數(shù)應(yīng)在106-107cfu/ml以上的要求,4℃保存的菌粉穩(wěn)定性高于25℃的。小中試發(fā)酵試驗(yàn)表明：嗜酸乳桿菌KLDSAD2發(fā)酵乳的組織狀態(tài)粘彈性最好。主體代謝產(chǎn)物試驗(yàn)表明：嗜酸乳桿菌代謝產(chǎn)乳酸量較大,而動(dòng)物雙歧桿菌代謝產(chǎn)乙酸量較大。應(yīng)用試驗(yàn)表明：成功設(shè)計(jì)菌粉吸管,可隨時(shí)放入經(jīng)常喝的各種飲料中,如礦泉水、果汁、營(yíng)養(yǎng)快線、以及盒裝牛奶等。 本研究篩選出具有抗胃腸道脅迫的益生菌,研究其以干物質(zhì)狀態(tài)的應(yīng)用方式,克服了益生菌在液體環(huán)境中的各種弊端,使菌粉飲料在保存1年后,活菌數(shù)仍在1.0×108cfu/g以上,使人體攝入的益生菌活菌數(shù)達(dá)到FAO/WHO的要求,為健康造福。
[Abstract]:Lactobacillus acidophilus and bifidobacterium are important probiotics in the human gut. Their number in the intestine is an important index to evaluate the health of the body. They have a variety of health care functions, such as acid and bile salt tolerance, adhesion to human epithelial cells, The colonized intestine produces bacteriocin, improves lactose intolerance, reduces cholesterol, ammonia and other toxic substances, produces B vitamins, returns to normal intestinal flora damaged by antibiotics, and stimulates immune response. At present, the key problem of probiotic products in China is the damage caused by gastrointestinal stress, such as manufacture, storage, sale and edible process. Bifidobacterium, Lactobacillus acidophilus and other probiotics, mostly anaerobes or facultative anaerobes, do not form spores during growth, so they have poor resistance, and some metabolites such as lactic acid and acetic acid, which are in danger of propagating themselves, are produced in life activities. The storage and transportation of probiotic products require cold chain and the shelf life is short. In view of the above disadvantages, this paper studies the application of probiotics as dry matter to realize the dietary supplement of probiotics at any time. In this study, five probiotics strains with better performance were selected by using bacterial ecology, physiology and 16s rDNA gene sequence analysis to study their probiotic characteristics. Secondly, the optimal freeze-dried protectant combination of five probiotics was optimized to study the preservation stability of each probiotic powder, and then to ferment the five probiotics in a small scale, from pH, titration acidity, The properties of texture and rheology were used to analyze and compare five kinds of fermented milk and to determine the content of main metabolites by HPLC. Finally the application mode of straw and bottle cap was determined. The probiotics test showed that both Lactobacillus acidophilus and Bifidobacterium animal had good tolerance to acid and bile salt, and the acid tolerance of animal bifidobacterium was stronger than that of 5 strains of probiotics of Lactobacillus acidophilus to Escherichia coli. Salmonella and Staphylococcus aureus had inhibitory effect, Lactobacillus acidophilus was stronger than bifidobacterium in animal, and the five probiotics were not resistant to penicillin, streptomycin and acetylspiramycin, and were sensitive to antibiotics penicillin, streptomycin and acetylspiramycin. The preservation stability test showed that the survival rate of 5 probiotics was 85.00%, 5 probiotics powder were stored at 4 鈩，

本文編號(hào)：1852507