Felipe M G, Vieira D C, Vitolo M, Silva S S, Roberto I C, Manchilha I M
Department of Biotechnology, Faculty of Chemical Engineering, Lorena, Brazil.
J Basic Microbiol. 1995;35(3):171-7. doi: 10.1002/jobm.3620350309.
The effect of acetic acid concentration on xylose-fermentation to xylitol by Candida guilliermondii FTI 20037 was evaluated in semisynthetic medium containing different concentrations of the acid. Increasing acetic acid concentration up to 1.0 g/l favored xylitol yield and productivity, with maximum values of 0.82 g/g and 0.57 g/l.h, respectively. The presence of acetic acid reduced cell production at all concentration. Furthermore, acetic acid was assimilated by the yeast together with the sugars and was depleted from the medium at concentrations of less than 3.0 g/l. The ability of this yeast to assimilate acetic acid suggests that these cells act as agents of medium detoxification. This behavior may lead to a viable microbiological process of xylitol production by C. guilliermondii FTI 20037 using xylose-rich lignocellulosic hydrolysates in which acetic acid is commonly present, causing inhibition of fermentative activity.
在含有不同浓度乙酸的半合成培养基中，评估了乙酸浓度对季也蒙毕赤酵母FTI 20037将木糖发酵为木糖醇的影响。将乙酸浓度提高到1.0 g/l有利于木糖醇产量和生产率，其最大值分别为0.82 g/g和0.57 g/l·h。在所有浓度下，乙酸的存在都会降低细胞产量。此外，酵母会将乙酸与糖一起同化，并且当浓度低于3.0 g/l时，乙酸会从培养基中耗尽。这种酵母同化乙酸的能力表明，这些细胞可作为培养基解毒剂。这种行为可能会导致季也蒙毕赤酵母FTI 20037利用富含木糖的木质纤维素水解产物生产木糖醇的可行微生物过程，其中通常存在乙酸，会抑制发酵活性。
