解脂耶氏酵母发酵产赤藓醇的条件优化

摘要：本实验中，我们采用一种常压室温等离子体（ARTP）突变系统对解脂耶氏酵母（Yarrowia lipolytica）进行诱变，获得赤藓醇产量最高的突变株M53。M53以100 g/L葡萄糖为底物，能够生成64。8 g/L赤藓醇，比野生菌株高69。2%，而副产物产量则远低于野生菌株。为了进一步提高赤藓醇产量同时抑制副产物的生成，我们对M53发酵培养基及发酵条件进行了优化。结果发现，葡萄糖和酵母提取物分别是最佳的发酵碳源及氮源。最终优化培养基为葡萄糖200 g/L，酵母提取物0。1 g/L，Cu2+ 4 g/L，Mn2+ 15 g/L，NaCl 40 g/L，在28℃、pH 3。0、200 rpm的发酵条件下，M53的赤藓醇产量为123。7 g/L。在5-L发酵罐中进行分批补料培养，经过168 h的发酵，赤藓醇产量达到154。6 g/L，且副产品产量较低。该结果表明M53具有用于赤藓醇商业生产的潜力。76760

毕业论文关键词：赤藓醇，常压室温等离子体诱变，解脂耶氏酵母，发酵优化，分批补料发酵

Abstract: In this experiment, we a new room temperature and atmospheric pressure plasma (ARTP) mutation system of high erythritol y。lipolytica (Yarrowia lipolytica) solution was mutated, the mutants。 In these mutants, M53 erythritol yield was the highest, we choose the strain for further study。 In batch culture, with 100 g/L glucose as substrate, M53 can produce 64。8 g/L erythritol, 69。2% higher than the wild type strain。 At the same time, the yield was also far lower than that of the wild strain。 In order to further improve the erythritol production also inhibited the formation of by-products, we of culture medium and fermentation conditions were optimized。 In the optimization experiment, glucose and yeast extract were the best carbon source and nitrogen source respectively。 The optimization of the final medium is 200 g/L of glucose, yeast extract 0。1 g/L, 4 g/L Cu2 +, Mn2 + 15 g/L, 40 g/L NaCl and culture temperature of 28 degrees, pH 3, the culture fermentation conditions of 200 rpm, M53 generation production of erythritol was 123。7 mg/L in。 Finally, we under the above conditions, in 5 L fermentor were fed batch culture, after 168 h of fermentation, erythritol yield reached 154。6 g/L, and byproduct production is low。 The results show that M53 has used for commercial production of erythritol。

Keywords: Erythritol, Room temperature and atmospheric pressure plasma mutagenesis system, Yarrowia lipolytica, Fermentation optimization, Fed batch fermentation

1 前言 4

2 材料与方法 5

2。1 菌株 5

2。2 培养基 5

2。3 培养方法 9

3 结果与讨论 7

3。1 高产赤藓醇突变株的筛选 7

3。2 碳源对M53赤藓醇发酵的影响 8

3。3 氮源对M53发酵赤藓醇的影响 9

3。4 金属离子的添加对M53赤藓醇发酵的影响 10

3。5 培养基pH、温度及搅拌速度对赤藓醇合成的影响 11

3。6 NaCl浓度对赤藓醇发酵的影响 12

3。7 5-L发酵罐中M53发酵赤藓醇的扩大培养 13

结论 16

参考文献 17

致谢 21

1 前言

赤藓醇（1,2,3,4-丁糖醇），一个四糖多元醇，在自然界分布广泛。作为一种代谢产物或贮存化合物，赤藓醇通常存在在地衣，大麻叶和蘑菇等天然产品中。在一些发酵的食物如酒，酱油及清酒也发现含有丰富的赤藓醇[1]。赤藓醇是一种低热量的甜味剂（热量为0。3 kcal/g），甜度为蔗糖的70-80% [2]。据说，人体摄入的90%的赤藓醇不能被人体代谢，而是随尿液直接排出体外而不改变血糖指数。此外，赤藓醇在动物毒理学和临床研究中已被证明是安全的甜味剂[3]。基于以上属性，赤藓醇已被广泛应用于特殊功能食品加工，是糖尿病、心血管病和肥胖病人饮食中理想的替代甜味剂[2]。此外，赤藓醇在口腔护理中可取代木糖醇，因为其不能被引起龋齿的细菌利用[4]。由此可见，赤藓醇在食品卫生保健中的需求日益增长，这使得其在我们的日常生活中日益重要。论文网解脂耶氏酵母发酵产赤藓醇的条件优化:http://www.youerw.com/shengwu/lunwen_88091.html