酶法合成聚甘油脂肪酸酯及其功能研究

发布时间：2018-11-11 20:55

【摘要】：聚甘油脂肪酸酯作为一种新型乳化剂,因具有天然、安全性高、HLB值范围宽,乳化稳定性好等诸多优点,目前在食品、日化、医药等领域应用广泛。本论文主要以不同链长的脂肪酸为原料,采用酶法绿色合成聚甘油脂肪酸酯产品,并研究其理化性质,以单甘酯作为对比,探讨合成的聚甘油脂肪酸酯产品在乳液及药物输送体系中的应用。本论文主要研究结果如下:第一,本论文研究并优化了聚甘油的合成方法。采用氢氧化钠作为催化剂,反应体系置于高温加热条件下,甘油脱去水分子合成聚甘油,并通过单因素试验法和正交试验法优化聚甘油的合成工艺,在最佳反应条件下得到聚合度为3.61、无刺激性气味的浅褐色聚甘油产品。经过分子蒸馏设备提纯后,最终可以得到纯度为86.33%的聚甘油,其中二聚甘油含量为68.30%,三聚甘油含量为13.13%,四聚甘油含量为3.18%。第二,本文采用固定化435脂肪酶在无溶剂体系下分别催化米糠油、樟树籽油、乙酸合成不同链长脂肪酸聚甘油酯。利用单因素试验和响应面试验优化反应条件,在最佳反应条件下,得到三种原料合成反应的平均酯化率分别为69.37%,67.34%和71.68%,并通过FTIR、HPLC/ESI/MS等方法鉴定了聚甘油酯产品的组成。第三,本文采用Griffin提出的方法,计算出自制聚甘油酯的HLB值皆大于7,为亲水性的乳化剂类型。以目前使用最为广泛的乳化剂单甘酯作为对照,研究自制聚甘油酯产品的乳化性、起泡性等。研究结果为:在长碳链脂肪酸聚甘油酯乳液制备的乳液中,使其静置稳定性、离心稳定性以及耐热稳定性表现最优的情况下,乳化剂的最小添加量分别为0.1%、0.1%、0.3%;在中碳链脂肪酸聚甘油酯制备的乳液中,使其静置稳定性、离心稳定性、耐热稳定性表现最优的情况下,乳化剂的最小添加量分别为0.3%、0.3%、0.3%。而短碳链脂肪酸聚甘油酯及单甘酯的乳化效果较差,乳液极不稳定,容易发生油滴聚结、油水分离的现象。在乳化剂添加量为0.3%时,由米糠油合成的聚甘油酯制备的乳液最稳定,粒径只有16.8nm;由樟树籽油合成的聚甘油酯制备的乳液起泡性和泡沫稳定性表现最佳,分别达到76.34%和92.96%。最后,本文选取在体内吸收效率低的姜黄素作为包埋对象,采用前体注入法制备姜黄素乳液包埋体系,利用单因素试验,考察原料用量、稳定剂用量、姜黄素用量对乳液包埋体系包埋率的影响。结果显示以上三个因素的最佳添加量分别为20%、0.1g、7%,在此条件下长、中、短碳链脂肪酸聚甘油酯及单甘酯的制备的姜黄素乳液包埋体系包埋率分别达到51.31%、43.01%、5.12%、58.96%。
[Abstract]:As a new emulsifier, polyglycerol fatty acid ester is widely used in food, daily chemistry, medicine and other fields because of its many advantages, such as natural, high safety, wide range of HLB value, good emulsification stability and so on. In this paper, polyglycerol fatty acid ester was synthesized by enzymatic green synthesis with different chain length fatty acids as raw materials, and its physical and chemical properties were studied, compared with monoglyceride. The application of synthetic polyglycerol fatty acid ester in emulsion and drug delivery system was discussed. The main results of this thesis are as follows: first, the synthesis method of polyglycerol is studied and optimized. Polyglycerol was synthesized by using sodium hydroxide as catalyst and the reaction system was heated at high temperature. The synthesis process of polyglycerol was optimized by single factor test and orthogonal test. A light brown polyglycerol product with polymerization degree 3.61 and no irritant odor was obtained under the optimum reaction conditions. After purification by molecular distillation equipment, the purity of polyglycerol was 86.33%, in which the content of dipolyglycerol was 68.30, the content of tripolyglycerol was 13.13 and the content of tetrapolyglycerol was 3.18. Secondly, the immobilized 435 lipase was used to catalyze rice bran oil, camphor seed oil and acetic acid to synthesize different chain length fatty acid polyglycerides in solvent free system. The reaction conditions were optimized by single factor test and response surface test. Under the optimum reaction conditions, the average esterification rates of the three synthetic reactions were 69.37% 67.34% and 71.68%, respectively, and the average esterification rates were 69.37% and 71.68%, respectively, by FTIR,. The composition of polyglycerol ester was identified by HPLC/ESI/MS and other methods. Thirdly, by using the method proposed by Griffin, the HLB values of self-made polyglycerides are all greater than 7, which is a hydrophilic emulsifier type. The emulsifying and foaming properties of polyglycerol products were studied by using the most widely used emulsifier monoglyceride. The results are as follows: in the emulsion prepared by long chain fatty acid polyglyceride emulsion, when the stability, centrifugal stability and heat stability of the emulsion are optimal, the minimum amount of emulsifier is 0.1% and 0.1%, respectively. 0.3; In the emulsion prepared by medium carbon chain fatty acid polyglyceride, the stability of the emulsion is stable, the stability of centrifugation and heat resistance is the best, and the minimum amount of emulsifier is 0.3% and 0.3%, respectively. The emulsification effect of short carbon chain fatty acid polyglycerides and monoglycerides is poor, the emulsion is very unstable, oil droplet coalescence and oil-water separation are easy to occur. When the amount of emulsifier was 0.3, the emulsion prepared by polyglycerol from rice bran oil was the most stable, and the particle size was only 16.8 nm. The foaming property and foam stability of the emulsion prepared from camphor seed oil were 76.34% and 92.96% respectively. Finally, curcumin with low absorption efficiency was selected as the entrapment object, and the curcumin emulsion embedding system was prepared by precursor injection method. The amount of raw material and stabilizer was investigated by single factor test. The effect of curcumin dosage on the entrapment rate of emulsion embedding system. The results showed that the optimum addition amount of the above three factors was 200.1g / 7.The entrapment rate of curcumin emulsion was 51.31, respectively, for the preparation of long, medium and short carbon chain fatty acid polyglycerides and monoglycerides under this condition, and the results showed that the entrapment efficiency of curcumin emulsion was 51.31%, respectively. 43.01 and 5.12, about 58.96.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O647.2

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