| The research and the exploitation of functional foods have been poured a new content into the food industry. The key about processing functional foods is the preparation of functional foods?base materials i.e. functional foods additives. The functional oligosaccharides have become a kind of important functional foods?base materials. Since they have some specific physiological functions ,such as promoting the multiplication of B~fidobacteria in intestines, keeping a good healthy for peoples, the functional oligosaccharides have been attached important to by the researchers all over the world. A xylooligosaccharide is composed of 2~? xylose. The link between the molecules is 3- 1,4 xylosidate band. It can be prepared by 13-xylanase reaction with corn cob, cotton seed hull or rapeseed hull. It抯 very difficult for xylooligosaccharide抯 digestion in intestines. The intestinal survivors of xylooligosaccharides are too much, and can keep a good multiplication for Bj/idobacteria. The utilization of the xylooligosaccharide is the highest among the other oligosaccharides. A maize is one of the three main foodstuff plants in China. The average yield of the corncob is about 40 million every year in China. Most of the comcobs are burnt, although a few are used.It抯 very important to do the theoretic researches and the processing technologies about the xylooligosaccharide preparation with corncobs.This dissertation studied the corncobs?components, the influences about the solubility of the xylan and lignin in the corncobs under the conditions of high temperature cooking and direct heat-ing explosion, and the preparation of the xylanase origin from the Streptomyces sp.E-86 strain at first. The embedded research about the enzyme reaction mechanism and the course of preparing xylooligosaccharide with the corncob had been done. A new method for plant separating xylooiigosaccharides had been given,also. The main detail research contents are as following:1. The influences of the sp.E-86 strain growing conditions on the different carbon source slants were observed. The conditions about the xylanase preparation made by the strain growing on these slants were studied. At the same time, the experiments conditions and the affecting factors of the fermentation were studied too. The experiments抮esults were as following: 1) The growing conditions of the sp.E-86 strain on the bran extracts slant or on the potato extracts slant were as same as that of on the slant of birch xylan. The bran extracts slant could instead of the birch xylan slant on the culture of the sp.E-86 strain at all. 2) the corncob xylan showed a very strong inductivity to the sp.E-86 strain producing xylanase, the enzyme activity, which carbon source was the corncob xylan, was 23 times higher than that of the birch xylan. 3) The enzyme activity produced from the sp.E-86 strain increased along with the advancing of the fermentation time. When the fermentation time got 24 hours, the enzyme activity reached the highest. The enzyme activity was low gradually after this fermentation time. 4) The pH increased along with the increasing of the fermentation time. But it showed a fall at the 12 hours.2. The devices about high temperature cooking and direct heating explosion experiments were built. The soluble laws of the xylan and the lignin in the corncob made by the two pretreatment methods under the mild experiment conditions such as 150 ~C to 170 ~C cooking temperature,4.9x 10~ to 9.8x 10~ explosion pressure, the different reaction time, the different proportion of the corncob with the water, the different soaking time of the corncob, were studied. The experiments?results were as following: 1) The solubility of the xylan in the corncob was increased with the reaction time advancing under the conditions of high temperature cooking anddirect heating explosion,but the pH was fall. 2) It抯 useful for the xylan in the corncob to increase its solubility along with the advance of the high temperature cooking抯 temperature or the direct heatin...
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