论文总字数：26837字

摘 要

微生物柴油具有可再生、环境友好等优点，被认为是石化柴油和植物柴油的理想替代品。然而，油脂合成体系原子收率低、产品体系单一，造成油脂合成过程经济效益低下，难以实现大规模生产。基于此，本研究提出了利用产油微生物——毛孢子菌Trichosporon porosum DSM 27194联产油脂与附加值化学品葡萄糖酸的策略，可为提高微生物油脂生产体系的经济性提供新的思路。具体研究内容如下：

（1）氮源种类考察：主要考察氮源对菌体生长及产物合成的影响。实验发现有机氮源可以促进油脂和葡萄糖酸的合成，经过174 h时发酵，油脂含量达细胞干重的36.97%，是对照组的1.76倍，葡萄糖酸产量为12.72 g/L，是无机氮源组的1.83倍。

（2）碳源浓度考察：主要考察葡萄糖浓度对菌体生长及产物合成的影响。实验发现高葡萄糖浓度不利于菌体生长却可以促进葡萄糖酸及微生物油脂的合成。菌株在含150 g/L葡萄糖的培养液中，经55 h发酵油脂含量达细胞干重的27.84%，是90 g/L葡萄糖组的1.41倍；并在144 h时有8.16 g/L葡萄糖酸生成，是90 g/L葡萄糖组的1.30倍以上。

（3）溶氧水平考察：主要考察溶氧量对菌体生长及产物合成的影响。实验发现通过高转速调节的高溶氧量会对菌体细胞造成损害，但有利于葡萄糖酸及微生物油脂的合成。菌株在高溶氧量条件下，经99 h发酵油脂含量可达细胞干重的29.33%，是低溶氧量组的1.20倍，并在124 h时，有8.28 g/L葡萄糖酸生成，是低溶氧量组的2.05倍。

关键词：Trichosporon porosum DSM 27194 微生物油脂 葡萄糖酸 联产 发酵调控

Co-production of microbial oil and gluconic acid using

Trichosporon porosum DSM 27194

ABSTRACT

Owning to the advantages of renewable and environmentally friendly, microbial oil has been recognized as an ideal substitute for petrochemical diesel and vegetable diesel. However, low product yield and single product recovery result in low economic benefits during microbial oil production, making it difficult to achieve large-scale production. Based on this, this study proposed a co-production strategy, in which oil and a value-added chemical of gluconic acid could be simultaneously produced by oleaginous yeast of Trichosporon porosum DSM 27194. This strategy provided a new a new way for improving the economics of the microbial oil production system. The specific research contents are as follows:

(1) Investigation of nitrogen source: mainly investigate the effects of nitrogen source on bacterial growth and product synthesis. Organic nitrogen source was found to promote the synthesis of oil and gluconic acid. After 174 hours of fermentation, the oil content reached 36.97% of biomass, which was 1.76 times than that of the control group. while 12.72 g/L of gluconic acid was also obtained, giving 1.83 times higher than control group.

(2) Investigation of carbon source concentrations: mainly investigate the influence of glucose concentration on bacterial growth and product synthesis. High glucose concentration caused some damage on cell growth, whereas, high glucose concentration did be conducive to gluconic acid and microbial oil production. 27.84% of lipid content has been obtained at 55 h with 150 g/L of glucose as carbon source, showing 1.41 times higher than control. And 8.16 g/L of gluconic acid has been obtained at 144 h, presenting 1.30 times higher than the control group.

(3) Investigation of aeration rate: mainly investigate the influence of aeration rates on bacterial growth and product synthesis. High dissolved oxygen brought by high speed has caused damage on the cell growth, but it is found to be conducive to the production of both gluconic acid and microbial oil. Under the condition of high dissolved oxygen, 29.33% of oil content was achieved after 99 hours of fermentation, which is 1.20 times that of the control group. At 124 h, 8.28 g/L of gluconic acid was obtained, presenting2.05 times higher compared with the control group.

Keywords: Trichosporon porosum DSM 27194; microbial oil; gluconate; co-production; fermentation control

目 录

摘 要 I

ABSTRACT II

第一章 文献综述 1

1.1 前言 1

1.2 产油微生物 1

1.3 微生物油脂 2

1.3.1 微生物油脂的性质及来源 2

1.3.2 微生物油脂的应用 3

1.4 葡萄糖酸 3

1.4.1 葡萄糖酸的性质及主要应用 3

1.4.2 葡萄糖酸的化学合成方法 4

1.4.3 葡萄糖酸的生物合成方法 4

1.5 本课题研究内容 4

第二章 不同氮源对T. porosum DSM 27194生长及产物合成的影响 6

2.1 前言 6

2.2 材料与方法 6

2.2.1 实验菌株 6

2.2.2 实验试剂和实验仪器 6

2.2.3 实验所需溶液 6

2.2.4 培养基 7

2.2.5 发酵操作过程 7

2.2.6 分析检测方法 8

2.3 结果与讨论 9

第三章 葡萄糖浓度对T. porosum DSM 27194生长及产物合成的影响 13

3.1 前言 13

3.2 材料与方法 13

3.2.1 实验菌株 13

3.2.2 实验试剂和实验仪器 13

3.2.3 实验所需溶液 13

3.2.4 培养基 13

3.2.5 发酵操作过程 14

3.2.6 分析检测方法 14

3.3 结果与讨论 14

第四章 溶氧量对T. porosum DSM 27194生长及产物合成的影响 17

4.1 前言 17

4.2 材料与方法 17

4.2.1 实验菌株 17

4.2.2 实验试剂和实验仪器 17

4.2.3 实验所需溶液 17

4.2.4 培养基 17

4.2.5 发酵操作过程 17

4.2.6 分析检测方法 18

4.3 结果与讨论 18

第五章 结论与展望 21

参考文献 23

附 录 26

致 谢 28

第一章 文献综述

1.1 前言

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