دانلود کتاب پیشرفت های فعلی در تولید بیوتکنولوژیک زایلیتول

Biotransformation of lignocellulosic biomass into biofuels and biochemicals offers numerous strategic and environmental benefits. One of the valuable compounds which can be made from lignocellulosic biomass is Xylitol. It is a commercially viable sugar alcohol that has several applications in the food, confectionaries, odontological, and pharmaceutical sectors. Based on the growing demand for xylitol, the US Department of Energy (USDOE) has included xylitol in the top 12 valueadded chemicals produced from lignocellulosic feedstock. Xylitol production from the hemicellulose hydrolysate is considered more profitable than ethanol or co-production of ethanol and furfural. Xylitol is a white crystalline powder, soluble in water, and similar in taste to table sugar with a lower calorific content, and it has anticariogenicity and antimicrobial properties, among other properties. Besides the common use of xylitol as a low calorific sweetener, it can be considered as a platform chemical for the chemical synthesis of xylaric acid, ethylene glycol, glycerol, etc. Therefore, in recent years, the commercial demand for xylitol has increased significantly. Currently, xylitol has a market of US$823.6 million which is expected to rise approximately to US$ 1.37 billion by 2025. Currently, this increased demandworldwide is being met through the chemical conversion of hemicellulosic hydrolysate. However, chemical synthesis has several environmental and sustainable challenges like high chemical requirements, high carbon footprints, high water usage, and reactor corrosions. In order to replace the chemical transformations, biotechnological methods of xylitol production have the advantages of being eco-friendly and sustainable.Xylitol production by microbial fermentation offers several unique advantages because it has a very low amount of inhibitors compared to the chemical synthesis. The fermentation broth after separation of biomass can be directly used for xylitol recovery and concentration using minimum steps of purification. The concentrated xylitol solution can also be directly used in the confectionaries or in toothpaste formulations avoiding the requirement of crystallization.