Glycerol as co-substrate in xylitol fermentation by Meyerozyma caribbica InaCCY67

Xylitol is an important bioproduct in the food and pharmaceutical industries. This research aimed to evaluate glycerol effect on xylose-to-xylitol bioconversion by Meyerozyma caribbica InaCCY67 in.YPX media. The glycerol concentrations were chosen based on the amounts produced during previous studies on xylitol production by M. caribbica InaCCY67. Medium without glycerol addition (control) and mediums containing glycerol (1 and 10 g/l) were also evaluated. According to the results, the addition of 1 g/l glycerol to the fermentation medium favored the yield (YP/S = 0.78 g/g) and the xylitol productivity (QP = 1.1 g/l/h). During the xylose-to-xylitol bioconversion, the formation of byproducts (glycerol) was observed for all conditions employed. Concerning the cellular growth, glycerol as the only carbon source for M. caribbica InaCCY67 was better than xylose or xylose and glycerol mixtures, resulting in a maximum cellular concentration (4.8 g/l).