摘要： 随着人们品位的不断提高，市场对天然香料的需求也随之增加，而通过生物法制备丙位癸内酯（GDL）的研究也受到越来越多研究人员和企业的重视。本文采用酵母菌生物法制备天然香料GDL，MF-Y11酵母作为菌种，利用蓖麻油酸作为发酵底物。当油水乳化到一定程度时，GDL的生成受到阻碍。为减少乳化对转化的影响，一是选择加入破乳剂打破乳化体系，提高产物GDL的产量。二是通过底物包埋实验，增加酵母对底物的利用率，降低底物对细胞的毒性，使包埋的底物可以在水中维持相对稳定。71233

选用破乳剂A01，在不补料的情况下按100ppm加入，GDL产量高达3.28g/L；选用破乳剂A02加入在补料10g/L蓖麻油酸的情况下按100ppm加入，生成的GDL产量最高，为3.44g/L，对照试验中，GDL在48h产量约为3g/L，说明加破乳剂有利于产物GDL的生成，且对细胞无毒性。

选用改性纤维与RA成1:1混合，在50℃的恒温水浴锅中搅拌0.5h，反应结束后产物达到4.5g/L，对照组生成的GDL约3g/L。而粒径大于80目的改性纤维与RA成1:1混合，在50℃的恒温水浴锅中搅拌0.5h，最有利于GDL的生成。由于包埋降低底物对于细胞的毒性，而且包埋的底物可以在水中维持相对稳定的粒径，很好的预防了乳化，促进了生物转化的进行，提高了产物GDL的产量。

毕业论文关键词： 丙位癸内酯（GDL）；蓖麻油酸；酵母菌；乳化；乳状液

Study on the Effect of System Emulsification on Transformation in the Preparation of Cetyl - caprolactone by Biological Method

Abstract: With the continuous improvement of people's taste, the market demand for natural spices also increased, and through the biological method of preparation of methyl decalactone (GDL) research has also been more and more researchers and enterprises attention. In this paper, natural spice GDL and MF-Y11 yeast were used as the strain, and ricinoleic acid was used as the fermentation substrate. When the oil and water to a certain extent, the formation of GDL is hampered. To reduce the impact of emulsification on the conversion, one is to join the demulsifier to break the emulsion system, improve the product GDL production. Second, through the substrate embedding experiment, increase the utilization of yeast substrate, reduce the substrate toxicity of the substrate, so that the substrate can be maintained in the water to maintain a relatively stable.

Use demulsifier A01, without adding the case of 100ppm by adding, GDL yield up to 3.28g/L; use demulsifier A02 added in the case of feeding 10g/L ricinoleic acid by 100ppm to join, the highest yield GDL , 3.44g/L. In the control experiment, GDL was about 3g/L at 48h, which indicated that the demulsifier was beneficial to the production of GDL and was non-toxic to the cells.

The modified fiber was mixed with RA 1:1, stirred in a constant temperature water bath at 50℃ for 0.5h, the product reached 4.5g/L after the reaction, the control group produced GDL of about 3g/L. While the modified fiber with particle size greater than 80 mesh was mixed with RA 1:1 and stirred for 0.5h in a constant temperature water bath at 50℃, which was the most suitable for the formation of GDL. As the embedding reduces the toxicity of the substrate to the cells, and the embedding of the substrate can maintain a relatively stable particle size in the water, the prevention of emulsification is facilitated, the progress of the biotransformation is promoted, and the yield of the product GDL is improved.

Key Words: Gamma Decalactone，ricinoleic acid，yeast，emulsification，Emulsion

目录

1、 绪论 1

1.1 GDL的概况 1

1.1.1 GDL的结构 1

1.1.2 GDL的物理化学性质