用于微生物培养基有机氮源的废酵母自溶液研究  

Preparation of Yeast Autolysis Solution Used as Organic Nitrogen in Microbial Medium

作　　者：田卓玲[1] 于慧敏[1] 沈忠耀[1] 

机构地区：[1]清华大学化学工程系

出　　处：《食品与发酵工业》2003年第5期1-6,共6页Food and Fermentation Industries

基　　金：国家"九五"科技攻关项目 (No.96 C0 3 - 0 2 );国家自然科学基金重点资助项目 (No.2 98341 0 3);国家自然科学基金资助项目 (No.2 98760 2 1 )

摘　　要：为进一步降低聚 β 羟基丁酸酯 (PHB)的生产成本 ,考察并优化了酵母自溶的影响因素与条件 ,探索采用廉价的废酵母自溶液作为有机氮源替代酵母浸粉的可行性。结果表明 ,自溶反应的最佳初始 pH为 7 0 ;加水比不仅影响酵母细胞的自溶速度和自溶效率 ,而且影响自溶产品的氨基氮终浓度 ,因此最佳加水比的确定取决于最终的经济核算。乙酸乙酯可以成功替代甲苯作为自溶促进剂 ,其优化用量为 3 %～ 4%。进一步以自制的酵母自溶液对重组大肠杆菌VG1( pTU 14 )进行摇瓶培养 ,结果表明 ,当以酵母自溶液为有机氮源替代酵母浸粉时 ,PHB浓度可以提高 2 2 7%以上。因此 ,废啤酒酵母自溶液在PHB的大规模生产中具有广泛的应用前景。To further decrease the production cost of poly β hydroxybutyrate (PHB), a new kind of organic nitrogen, yeast autolysis solution, was attempted to take the place of yeast extract during fermentation process of recombinant E coli VG1 (pTU14) The conditions of yeast autolysis solution were optimized The results showed that the autolysis of yeast reacted best under initial pH of 7 0 With the increase of water ratio, the speed of autolysis and the yield of amino nitrogen were enhanced, but the concentration of amino nitrogen was reduced, which resulted in the increase of energy cost for condensation Toluene was an accelerant for the reaction of autolysis, but an inhibitor for the growth of cell, in the mean time In order to avoid the bad influence of toluene to normal growth of recombinant cells, ethyl acetate was tried instead of toluene Further results of cell culture using the yeast autolysis solution of the discarded beer yeast showed that the optimized concentration of ethyl acetate was 3%～4% of dry cell weight The results of 48 h shaking culture of VG1 (pTU14) showed that it was about 22 7% higher of PHB concentration than that of using yeast extract, when using the yeast autolysis solution as organic nitrogen Therefore, the application of autolysis solution of discarded beer yeast possessed promising prospect in the scale up production of PHB

关 键 词：酵母自溶液 啤酒废酵母 有机氮源 氨基氮浓度 聚β-羟基丁酸酯生产 高分子材料 

分 类 号：TS261[轻工技术与工程—发酵工程]