摘要
以柠檬酸生产菌株为出发菌株采用传统诱变手段和定向驯化相结合的方法,选育获得一株耐高温柠檬酸发酵突变菌株F-97。该菌株与出发菌株在初糖浓度为189.72 g/L下进行对比,发酵温度为37℃时,F-97的柠檬酸产量达到164.39 g/L,转化率为86.45%,出发菌株产酸仅108.25g/L,说明F-97具有很强的耐高酸高糖特性。发酵温度为40℃时,F-97的柠檬酸产量为157.82 g/L,出发菌株产酸仅83.26 g/L,说明F-97同样具有优异的耐高温特性。但F-97的发酵残糖较高,通过发酵工艺优化,确定最佳工艺条件。在最佳发酵控制条件下,柠檬酸产量由157.82 g/L提高至177.74 g/L,转化率提高约14%,发酵周期缩短了4 h,残糖降低至6.23 g/L。通过进一步实验确定,剩余残糖不能被F-97利用。
The compound mutation of ultraviolet （UV）, high-temperature and nitrosoguanidine （NTG）, combined with domestication technology, was developed to breed the high-temperature, high-acid, high-sugar resistant strain by directional selection. Finally, we got a mutation strain F-97, that had a high genetic stability. Contrasted with starting strain, the yield of citric acid for F-97 was 164 g/L, corresponding, starting strain was only 108 g/L under the initial glucose concentration was 189.7 g/L, incubation temperature was 37 ~C. This showed that F-97 had high-acid, high-sugar resistance. When the incubation temperature was 40 %, the yield of citric acid for F-97 was 157 g/L, the starting strain was only 83.2 g/L. This showed F-97 also had high-temperature resistance. However, F-97 had amount of residual sugar left, the optimum conditions were achieved by process optimization. The yield of citric acid achived 177.74 g/L from 157.82 g/L, percent conversion enhanced by 14%, fermentation period was shortened by 4 hours, Residual sugar droped to 6.23 g/L. F-97 couldn＇t use this residual sugar by further experimental study.
出处
《食品科技》
CAS
北大核心
2014年第10期26-31,共6页
Food Science and Technology
基金
山东省自主创新专项(2012CX20505)
关键词
高温
高酸
高糖
复合诱变
驯化
high-temperature
high-acid
high-sugar
compound mutation
domestication
