Study On Xylitol Production Of Wine Lees Hydrolysate By Microencapsulated Candida Tropicalis Cells

Xylitol (CH₂OH-CHOH-CHOH-CHOH-CH₂OH) is a naturally occurring five-carbon polyalcohol, It's sweetening power is similar to sucrose, it has anticariogenic properties; It is used as a nutrition and a cure for diabetes patients because it is independent on insulin to metabolize and it can regulate abnormity of metabolism. It is also used for salvaging acetone-body patients because of its resisting acetone-body efect. It has good heat-stability and never reacts with amino acids under heating, so it is confected all kinds of preparations for nutrition medicines together with amino acids. As a result, it is applied abroadly in food, medicine, and light industry.Xylitol is produced mainly by chemical method in industry from high pure xylose. However, the chemical process presents some disadvantages, such as the necessity of purifying xylose present in the hydrolysate, difficulty of separation and callback catalyzer, low production of xylitol, high cost of production and serious pollution in environment. Therefore, these drawbacks encouraged many researchers to look for alternative ways to produce xylitol.Nowadays, its microbiological production of xylitol by fermentation of hemicellulosic hydrolysates is very attractive because of several advantages, such as the use of mild conditions of pressure and temperature. In addition, since microorganisms, mainly yeasts, are able to directly convert xylose into xylitol from the hydrolysate, there is no need of xylose purification .The biotechnological produ-...