Study Of The Preparation, Activity And Application Of L-arabinose From Corncob

L-arabinose, a kind of rare sugar, which has already become newly developed functional saccharide with many beneficial biomedical and health effects. It is usually exist in the pentin, hemicellulose and pectic acid of higher plants in the form of heteropolysaccharide such as araban, arabinoxylan and arabinogelose. L-arabinose is odorlessness, heat-resisting, and has a high stability of acid, and the sweet taste is similar to that of sucrose, but approximately half of the sweetness. Inhibition of blood glucose is the main function of L-arabinose. Limited by its production method, L-arabinose is expensive in present international market, which limits its application and popularity in the food and medical industry. Therefore, reducing the preparation cost and improving the yield are necessary. So it is of great significance to seek a preparation method of L-arabinose with high yield. This dissertation systematically studied the optimization of preparing process of L-arabinose from corncob, analyses of components in the hydrolysate, activity and its application in the biscuits.Firstly, the composition of corncob was analyzed. The results indicated that crude fiber content, soluble sugar content, reducing sugar content, protein content, fat content,crude ash content, moisture, xylogencontent of corncobs were amounted to 43.34%±0.49%, 0.34%±0.01%, 0.13%±0.01%,0.07%±0.01 %, 0.67%±0.02%,1.87%±0.03%, 12.06%±1.23%, 28.47%±0.87%, respectively.Components in the hydrolysate were detected by the methods of TLC, HPLC and High-efficient Thin Layer scanning analysis. Three kinds of monosaccharide (D-xylose,L-arabinose, glucose) were detected by HPLC analysis, and the amount of L-arabinose was 22.32%±0.33%. The optimum conditions of preparation were obtained by single factor and orthogonal experiments: temperature 90?, holding time 5h, concentration of oxalic acid 6%, solid-liquid ratio 1:12, and the highest L-arabinose yield was 14.89%±0.12%.In the activity inhibition of a-glucosidase research test, inhibition rate of L-arabinose was detected by comparing to acarbose. The result showed that the inhibition rate was up to 39.93%±0.26% when the substrate concentration of 1.6 mg/mL.L-arabinose extracted from corncob was applied to functional biscuit production.The optimum parameters of biscuit were derived by orthogonal experiments: xylitol 20%,butter 25%, egg 5%, baking temperature 190? and L-arabinose 25%. Production process and relevant quality standards were confirmed and the detection results showed that indexes of the product conforming to the state standards.