Study On The Preparation, Quality And Physiological Function Ofα-Galactooligosaccharides From Chickpeas

a-galactooligosaccharide is one of functional oligosaccharides, the main way to obtain it is extracted from natural legume, of which extracted from soybean has been researched extensive, and applied to many fields, such beverages, yogurt, health food, etc. However, in a-galactooligosaccharide which from soybeans, the content of sucrose is relative high, which restrict its application in obesity. Compared with soybean, in chickpea the content of α-galactooligosaccharide is higher, and sucrose is relative lower, so it may extend the limited application of soybean oligosaccharide which due to the high content of sucrose. This article mainly research on the preparation of a-galactooligosaccharide from chickpea, probiotic properties to intestine, restrict function to cancer cell, stability and so on.Firstly, soluble sugar was extracted from chickpea, then the extracting solution was isolated and purificated through activated carbon-diatomate (1:1, w/w) medium pressure chromatography column, sugar content was analyzed by phenol-sulfuric acid method and HPLC, samples of a-galactooligosaccharide content of90%,80-90%,70-80%were obtained successively. In the samples, the content of sucrose was lower compared with soluble sugar in extracting solution.Secondly, a-galactooligosaccharide of85%purity was chosen, and the stability in heat treatment, acid treatment, Maillard reaction characteristic in heat process were researched, α-galactooligosaccharide samples prepared from chickpea has good stability on heat treatment. When heated at100℃, residual rate of a-galactooligosaccharide was still as high as94.27%, while residual rate of sucrose was relative low in the same treat condition. In acid treatment, the stability of a-galactooligosaccharide samples was also good, when the pH was3.0, the residual rate of the samples was still94.95%. It can be seen in the research on Maillard reaction, the Maillard reaction degree of a-galactooligosaccharide samples prepared was worse than glucose, reaction time was3h, the browning level of samples prepared was70.65%relative to glucose.Thirdly, anaerobic fermentation cultivation was carried out for a-galactooligosac-charide of different purities prepared by anaerobe faecal fermentation in vitro, and the change of the amount of beneficial bacterium, harmful bacterium, total bacterial were detected by fluorescent in situ hybridization, and evaluate the prebiotic function of tested substrate by prebiotic index. The a-galactooligosaccharide of the highest purity was of the best effect on the proliferation of beneficial bacterium, and the most restrain effect on harmful bacterium, and of the highest prebiotic index of2.00; in addition, the variation of different short chain fatty acid in the fermentation process was detected by HPLC, and the a-galactooligosaccharide of the highest purity produce highest amount of short chain fatty acid used by intestinal microorganism.Fourthly, discuss the effect of a-galactooligosaccharide which was prepared from chickpea on the growth of human gastric cancer BGC-823cells. By comparation, for the same sample, with the increasing of concentration, the inhibition rate to cancer cell increased; at the same concentration, with the increasing of cultivating time, the inhibition rate to cancer cell increased as well. However, for a-galactooligosaccharide of different purities prepared, in the same cultivation condition, the inhibition rate to human gastric cancer BGC-823cells varied little.