Production of xylitol by Debaryomyces hansenii , the yeast strain isolated from pollen of Malva sylvestris flower

Xylitol is a naturally five – carbon polyol with a high sweetening power. Xylitol is the sweetest among the polyalcohols. The biotechnological method of producing xylitol by microorganisms has been studied as an alternative to the chemical method and is very environmentally safe. Xylitol is an attractive sugar substitute for use in the food-processing, nutritional supplement and pharmaceutical industries. Among the microorganisms, yeasts are considered as the best xylitol producer. The purpose of this study was xylitol production by Debaryomyces hansenii that isolated from pollen of Malva sylvestris flower. This strain was identified by 18SrRNA sequencing and following its alignment with existed similar strains in data bases. Xylitol was produced in production medium contained xylose and other compounds. Xylitol was first identified by thin layer chromatography (TLC) method then it was confirmed by Megasyme kit. Xylitol concentration was quantified using high performance liquid chromatography ( HPLC) method. This strain produced 20.45 g l-1 xylitol after 48 hours culture incubation in medium contained 40 g l-1 xylose.