【作者】 曾里；

【导师】 刘世贵； 李大平；

【作者基本信息】 四川大学 ， 遗传学， 2003， 硕士

【摘要】 工业乳化液的破乳是现代工业的一个重要课题。本研究工作的目的就是为生物破乳剂的工业应用的可行性提供生物学实验依据。根据乳化液的性质，分别采用了不同的分离和筛选策略获得了高效生物破乳菌。针对W／O型乳化液，首先利用富集、筛选，获得了高生物活性的生物表面活性剂。再利用建立的W／O型工业模拟乳状液初筛和油田原油乳化液复筛体系，找到了3支针对W／O型乳化液高效破乳的生物破乳菌。根据形态及生理生化实验的鉴定有2支菌为属棒状杆菌属，1支菌为芽孢杆菌属；针对O／W型乳化液，在K.L. Janiyani等研究的启发下，直接从枯草芽孢杆菌中筛菌。采用O／W型工业模拟乳状液进行初筛，通过工业机床乳化液(O／W型)进行复筛，得到了2支针对O／W型乳化液高效破乳的枯草芽孢杆菌。为了进一步研究生物破乳菌的破乳活性，本论文还重点对菌株的微生物学和生化代谢进行了详细的研究。进行了培养基、pH、温度、时间等环境因素对菌株生长及破乳活力的影响测定实验，找到了有利于破乳剂产生的最适发酵条件。在最佳条件下，针对W／O乳化液，破乳时间在24H内，破乳率都大于80％；针对O／W乳化液，破乳时间在0.1H内，破乳率大于80％。同时我们的研究证明，针对W／O乳化液，3株破乳菌的四川人学硕卜学位论文破乳活性均与细胞本身有关，只有在细胞保持完整的前提下，细胞表面产生的破乳剂刁‘具有破乳活性，这种破乳剂一旦生成，具有热稳定性。而乳状液含水量越多，含粘土量越少，破乳速度越快，一定振荡有利于破乳，但破乳活性受温度影响不大。针对0柳乳化液，具有破乳效果的物质不是干细胞本身，而是存在于除去细胞的培养液里。这验证了具有破乳效果的是一种次生代谢产物。它的破乳活性与细胞的完整性无关。其破乳活性与破乳温度无关，但与乳化液的含水量有关，含水量越高越不利于破乳。本研究关于生物破乳菌的微生物学及针对破乳活性进行的代谢过程的研究对于解决工业乳化液的破乳具有一定的理论意义，对于开发工业生物破乳剂，代替工业化学破乳剂具有一定的实践应用价值。更多还原

【Abstract】 One of the major problems associated with industry was the generation of emulsions. De-stabilization of the emulsions is therefore necessary to it, the objective of the present research was to provide biologically experimental evidences for the future industrical applications.According to the qualties of emulsions,different tactics were taken for isolation and screening of bacteria to high de-emulsification activity.For w/o emulsions,the methods were to enrich and isolate organisms,we frist collected the bio-surfactants, for high activity.By the procedures of primary screening in which w/o emulsions of industry simulant was de-emulsificated and of secondary screening in which the oil field emulsions was de-emulsificated, three strains of de-emulsifying bacteria were screened. On the basis of their morphological observation and physiological and biochemical tesrs, two strains of them were classified as the genus of Corynebacterium Lehmann of Neumaun and the another was classified as the genus of Bacillus; For o/w emulsions, base on the idea of K. L. Janiyani’ research, we screened the de-emulsifying bacteria from the genus of Bacillus directly. The way of screening as soon as the former, two strains of Bacillus for high de-emulsification activity for o/w emulsions. To investigate and verify the activity of these strains, a moredetailed study was conducted to the microbiology and biochemical metabolism of the strains. The effects of the environmental factors such as culture medium, pH, temperature and time for growth and de-emusif ication activity were studied , we foud the most favorable condition for of bio-de-emulsifier. On the base of the condition, these bacillus can recovery of 80% oil from w/o emulsions within 24 hours and recovery of 80% oil from o/w emulsions within 0. 1 hours. At the same time , our research suggest that , for w/o emulsions, De-eulsification activity of the three strains of demulsifiers had contact with cell. Under the condition of keeping integrality of the cells, they can de-emulsificated. The were stable under heating. The more aquiferous quantity, the less clay quantity is, the more efficient de-emusificated.And Surge have little affect on efficient . For the o/w emulsions,the de-emulsifier lies in the the cell-free broth. It demonstrated that the de-emulsifier is a metabolite of metabolism which have nothing to do with cell and temperture. But aquiferous quantity of emulsions affected remarkably for activity, of de-emulsificated. The more aquiferous quantity is, the less efficient de-emusification.The study of microbiology of de-emulsifying bacteria and metabolism for de-emusification activity is of practical value i n relation to develop technology to solve problems of de-emusification for industry emulsions and to produce bio-de-emusifier.更多还原