Study On Choline Glycine Ionic Liquid To Promote Starch Butyrylation Reaction And Its Application

This article uses corn starch as the raw material and choline glycine ionic liquid([Cho][Gly])as the research object to study the promotion effect of different concentrations of [Cho][Gly]-water mixture on starch butylation reaction,as well as the regulatory effect of reaction temperature and concentration of [Cho][Gly]-water mixture on starch butylation reaction.The prepared butyrylated starch was used as the nano micellar carrier of hydrophobic active substance curcumin to prepare curcumin nano micelles for colon administration.The research results of this article provide a theoretical basis for the application of choline amino acid ionic liquids in the chemical modification of starch,and broaden the scope of starch application.The main research content is as follows:1.The [Cho][Gly]-water mixture can promote the starch butylation reaction,and the characteristics of butylated starch change with the concentration of the[Cho][Gly]-water mixture.Debranched corn starch undergoes butylation reaction in different concentrations of choline glycine ionic liquid water mixture([Cho][Gly]with a mass ratio of 0:10,4:6,5:5,6:4,7:3,8:2,and 10:0,respectively)to study the effect of [Cho][Gly] on starch butylation reaction.The presence of characteristic peaks of butyryl groups in the nuclear magnetic resonance hydrogen spectrum and Fourier transform infrared spectrum of butyrylated starch samples indicates the successful butylation reaction.The results of nuclear magnetic resonance hydrogen spectroscopy indicate that the mass ratio of [Cho][Gly] to water is 6:4,which has the best promoting effect on the starch butylation reaction,increasing the degree of butyryl substitution from 0.13 to 0.42.X-ray diffraction results showed that the crystal structure of starch modified in [Cho][Gly]-water mixture changed from B-type crystal structure to a mixture of V-type crystal structure and B-type crystal structure allotropy.When the ratio of [Cho] [Gly] to water is 8:2,the characteristic peak of the V-shaped crystal structure of butyrylated starch is the strongest,and its thermal stability is also the strongest.According to in vitro digestion results,under this reaction condition,the content of resistant starch in the sample increases from 25.42%to 46.09%.2.The changes in reaction temperature and the concentration of[Cho][Gly]-water mixture can regulate the properties of butyrylated starch.The study found that the samples with the highest degree of butyryl substitution among the three reaction temperature groups were IL: W-8:2-80(0.435),IL: W-6:4-90(0.420),and IL:W-4:6-100(0.294),which showed significant differences(0.227,0.130,and 0.109)compared to the modified butyryl starch in the aqueous phase at the same temperature.The lower the reaction temperature,the higher the value of the maximum degree of butyryl substitution.X-ray diffraction results showed that the internal structure of butyrylated starch changed into a mixture of V-shaped crystal structure and B-shaped crystal structure allotropy,and the higher the reaction temperature,the stronger the characteristic peak of V-shaped crystal structure in starch.The conclusion of the study indicates that the promoting effect of choline glycine ionic liquid on starch butylation reaction is affected by changes in reaction temperature.By changing the concentration of choline glycine ionic liquid water mixture and reaction temperature,two types of butyryl starch with high degree of substitution or thermal stability,as well as high content of resistant starch,can be prepared to meet different needs.3.Curcumin is a kind of hydrophobic natural active substance,and the nano micellar carrier of curcumin was prepared from butyrylated starch.Curcumin nano micelles were characterized and their release characteristics in simulated gastrointestinal fluid were studied.The results showed that the prepared curcumin nano micelles of butyrylated starch with higher degree of butyryl substitution had higher drug loading(8.43%)and encapsulation efficiency(84.27%).In addition,curcumin nano micelles showed a good sustained-release effect in the simulated solution of stomach and small intestine,indicating that curcumin nano micelles had a good colon drug delivery function.