Forough Asgary Karchegany; Marzieh Shamee; Gholamreza Ghezelbash; Iraj Nahvi
Abstract
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 ...
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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.
Marjan Enshaeieh; Mahboobeh Madani; Azadeh Abdoli; Iraj Nahvi; Forough Asgary Karchegany
Abstract
The application of microorganisms in the production of economically valuable products has attracted a great attention in recent years. These valuable materials such as single cell oil and poly-alcohols have potential for application in various industrial fields. Single cell oil in biodiesel production ...
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The application of microorganisms in the production of economically valuable products has attracted a great attention in recent years. These valuable materials such as single cell oil and poly-alcohols have potential for application in various industrial fields. Single cell oil in biodiesel production and poly-alcohols such as xylitol in the food and pharmaceutical industries, are valuable. In this study high production of SCO was evaluated and analyzing of SCO was done by FTIR spectroscopy. In addition, xylitol production by the yeast, in the media containing xylose was done and xylitol was analyzed by using colorimetric method. Optimization of microbial oil and xylitol production was done by Taguchi method and valuable results were obtained. This strain was reached to SCO production and dry biomass of 10.21 g/L in optimum condition including 100 g/L glucose, 72 h incubation time, pH = 5, temperature of 25 ºC and rpm=180. In addition, in the medium with 140 g/L of xylose, xylitol production was 54.99 g/L. The results of this study can show that there are native yeasts with high potential of producing valuable materials which can be directed to produce the desired products by providing appropriate medium condition.
