Department of Chemical Engineering, University of Vigo (Campus Ourense), Spain.
Prep Biochem Biotechnol. 2012;42(1):1-14. doi: 10.1080/10826068.2011.552145.
Biosynthesis of xylitol using the yeast Debaryomyces hansenii NRRL Y-7426 was carried out using distilled grape marc (DGM) hemicellulosic hydrolysates directly concentrated by vacuum evaporation or after detoxification with activated charcoal. The effect of nutrient supplementation with vinasses, corn steep liquor (CSL) or commercial nutrients was explored. Using crude concentrated hemicellulosic hydrolysates, the maximum xylitol concentration, 11.3 g/L, was achieved after 172 hr (Q ( xylitol ) = 0.066 g/L-hr; Y ( xylitol ) (/SC) = 0.21 g/g); meanwhile, using detoxified concentrated hydrolysates, the concentration increased up to 19.7 g/L after 72 hr (Q ( xylitol ) = 0.274 g/L-hr; Y ( xylitol ) (/SC) = 0.38 g/g). On the other hand, using crude or detoxified hydrolysates, the xylose-to-xylitol bioconversion was strongly affected by the addition of nutrients, suggesting that these hydrolysates present essential nutrients favouring the growth of D. hansenii.
使用酵母德巴利酵母 NRRL Y-7426 进行木糖醇的生物合成，使用通过真空蒸发直接浓缩的蒸馏葡萄渣（DGM）半纤维素水解物或用活性炭解毒后的半纤维素水解物。探讨了添加酒糟、玉米浆（CSL）或商业营养物的营养补充的效果。使用粗浓缩半纤维素水解物，在 172 小时后达到 11.3 g/L 的最大木糖醇浓度（Q（木糖醇）= 0.066 g/L-hr；Y（木糖醇）/（SC）= 0.21 g/g）；同时，使用解毒浓缩水解物，在 72 小时后，浓度增加到 19.7 g/L（Q（木糖醇）= 0.274 g/L-hr；Y（木糖醇）/（SC）= 0.38 g/g）。另一方面，使用粗或解毒的水解物，木糖到木糖醇的生物转化受到营养物质添加的强烈影响，表明这些水解物含有有利于德巴利酵母生长的必需营养物质。
