(448c) Fermentation Process Optimization for Enhancing D-Arabitol Production Performance in a Novel Strain of Wickerharmomyces Anomalus BKK11-4

D-Arabitol, also known as arabinitol, is an important pentitol compound. It has been listed in the top 12 biobased building block chemicals in polyols group compounds that targeted further development of industrial biotechnology and research. D-Arabitol is widely used in many consumer products as an ideal sugar substitute for diabetes patients, including artificial sweeteners, and oral healthcare products, herbicides, and antipathogenic disease medicines. D-Arabitol can be also used as an intermediate for chemical synthesis such as xylitol, propylene glycol, and ethylene glycol. To date, arabitol is commercially produced by the chemical reduction of arabinonic acid lactones. The drawbacks of the chemical synthesis include consumption of costly catalysts, operation under high temperature (100 °C), and difficulty in product separation and purification in downstream recovery. Arabitol production via biosynthesis platform has therefore attracted more interest as the alternative production route. The challenge for biotechnologists is to understand the fundamental knowledges on sugar metabolism by microbes for enhancing arabitol production. Yeasts have been selected as the potential microbes for biosynthesizing sugar alcohols including arabitol. Here, we present our in-house osmotolerant yeast isolate Wickerharmomyces anomalus BKK11-4 as the biofactory to produce D-arabitol. W. anomalus BKK11-4 could ferment high glucose concentration of 200 g/L for D-arabitol under aerobic conditions. Mixing and aeration were found to influence fermentation productivity and yield. Complete sugar consumption was observed at high agitation and aeration rates. While organic nitrogen source like yeast extract mainly controlled fermentation productivity and carbon flux ratio to D-arabitol.