【作者】 黄大坚；

【导师】 傅童生； 肖兵南；

【作者基本信息】 湖南农业大学 ， 临床兽医， 2007， 硕士

【摘要】 以邻苯二甲酸醋酸纤维素（CAP）为壁材，将保加利亚乳酸杆菌进行微胶囊化，制成含有活菌的微胶囊，一方面能在口服该菌时起到保护及免受胃酸灭活作用，继而能在肠道中崩解释放出活菌并进行增殖，起到调节肠道中微生态平衡的效果；另一方面能保护活性保加利亚乳酸杆菌免受外界不良环境的影响，从而延长保加利亚乳酸杆菌生物制剂的保存期。在制备用于微胶囊的保加利亚乳酸杆菌中，首先以菜籽油为分散介质，在初步的乳化条件中，最佳的乳化条件为：邻苯二甲酸醋酸纤维素的浓度为3％、表面活性剂Span-80的浓度为2％、Tween-20的浓度为0.05％、明胶的浓度为3％、搅拌速度为900 r／min、乳化温度为37.5℃。通过最佳乳化条件制备的乳液，采用单凝聚法制备保加利亚乳酸杆菌微胶囊，用50％硫酸铵溶液，使菜籽油中的壁材CAP析出，形成初步的微胶囊，过滤，取上层微胶囊油液，缓慢注入3％CAP和1.5％明胶混合液中，进行第二次乳化，在200r／min的搅拌速度下乳化5min，用冰醋酸调节乳液的pH值至3.0，固化30min，取乳液置于喷雾干燥机中进行喷雾干燥。制成样品。通过测定微胶囊产品的包埋率、样品活菌总数、耐酸性、人工胃液、人工肠液消化作用、贮藏稳定性和实验耐热性实验等，对微胶囊产品的质量进行评估。测定结果发现，通过此工艺制备的微胶囊产品的包埋率为72.4％，样品中的活菌总数为5.53×10¹²CFU／g，经过人工胃酸消化1h，微胶囊产品中仍保持有较高的活菌数：2.18×10⁸CFU／g，且未见有微胶囊溶解现象；在人工肠液中消化60min，微胶囊中的活菌数仍5.49×10¹¹CFU／g；在加速实验中，40℃保存35d后，样品中的活菌数仍能达到1.50×10⁸CFU／g，50℃保存3h后，样品中仍能保持较高的活菌数5.11×10⁸CFU／g。实验证明，通过微胶囊化后的保加利亚乳酸杆菌具有较好的稳定性。更多还原

【Abstract】 This paper mainly narrated about the preparation of microcapsule of lactobacillusbulgaricus. The cellulose acetate phthalate （CAP） was used as the wall material, andlactobacillus bulgaricus was enwrapped as core of the microcapsule. On the one hand,the microcapsulation can protect the lactobacillus, so the lactobacillus could live andbreed in feed of animals, and play an important part in regulation of intestine microe-cological balance; On the other hand, the microcapsulation can protect lactobacillusfrom the outside adverse environmental, extending retention period of probiotics.In order to get the microcapsule which enwraps high success ratio of lactobacil-lus, we need developed a new emulsification method which can protect the activity oflactobacillus during the spray drying process. Firstly, rapeseed oil was used as adispersion medium when water was emulsified in the initial period, the concen-tration of emulsification were: CAP:3%, Tween-20:0.05%, Span-80:2%, glutin: 1.5%,mechanical stirring speed:900r/min,and the emulsification temperature was 37.5℃.Under the optimum conditions, the lactobacillus bulgaricus microcapsule was madeby single agglomerate, and precipitated the wall with located in rapeseed oil with 50%ammonium sulfate solution; The preliminary micro-emulsion filtrated, then drawsome microcapsule from the micro-emulsion and progressing the second emul-sification, injecting a mixture with 3% CAP and 1.5% gelatin into the micro-emulsion,and keep the stirring speed 200r/min for 5 minutes, adjusting pH as 3.0 with aceticacid, then desiccating with the spray drier after 30 minutes. At last, got the prodtictof microcapsule powder.The quality of microencapsulation product was assessed by measuring the emb-edding rate, living total germ in microcapsule, and acid-tolerance ability in artificialgastric fluid, dissolved in artificial intestine fluid, storage stability and ant-heatexperiment. As the results showed that this process for the preparation ofmicroencapsulation embedded 72.4%, the concentration of alive germ in the microca-psulation was 5.53×10¹²CFU/g. Artificial stomach acid digestion one hour andmicrocapsule remain high concentration of viable germ was microencapsulation products remained high viable germ: And there was 2.18×10⁸CFU/g. There was nomicrocapsule dissolved in intestinal digestive 60 minutes. Concentration of alive germin microcapsule was 1.50×10⁸ CFU/g, In expediting the experiment the concen-tration of being viable germ of samples was 5.11×10⁸ CFU/g after 3 hours at 50℃,the results showed that microencapsulation can improve the stability of lactobacillibulgaria.更多还原