Premium
Increase of xylitol production rate by controlling redox potential in Candida parapsilosis
Author(s) -
Oh DeokKun,
Kim SangYong,
Kim JungHoe
Publication year - 1998
Publication title -
biotechnology and bioengineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.136
H-Index - 189
eISSN - 1097-0290
pISSN - 0006-3592
DOI - 10.1002/(sici)1097-0290(19980520)58:4<440::aid-bit11>3.0.co;2-f
Subject(s) - xylitol , redox , fermentation , aeration , chemistry , xylose , food science , reduction potential , biochemistry , inorganic chemistry , organic chemistry
Abstract The effect of redox potential on xylitol production by Candida parapsilosis was investigated. The redox potential was found to be useful for monitoring the dissolved oxygen (DO) level in culture media, especially when the DO level was low. An increase in the agitation speed in a 5 L fermentor resulted in an increased culture redox potential as well as enhanced cell growth. Production of xylitol was maximized at a redox potential of 100 mV. As the initial cell concentration increased from 8 g/L to 30 g/L, the volumetric productivity of xylitol increased from 1.38 g/L · h to 4.62 g/L · h. A two‐stage xylitol production strategy was devised, with stage 1 involving rapid production of cells under well‐aerated conditions, and stage 2 involving cultivation with reduced aeration such that the culture redox potential was 100 mV. Using this technique, a final xylitol concentration of 180 g/L was obtained from a culture medium totally containing 254.5 g/L xylose in a 3,000 L pilot scale fermentor after 77 h fermentation. The volumetric productivity of xylitol during the fermentation was 2.34 g/L · h. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 58:440‐444, 1998.