TY  - JOUR
AU  - Anastassiadis, A.
AU  - Aivasidis, A.
AU  - Wandrey, C.
AU  - Rehm, H.-J.
TI  - Process Optimization of Continuous Gluconic Acid Fermentation by Isolated Yeast-Like Strains of Aureobasidium pullulans
JO  - Biotechnology & bioengineering
VL  - 91
SN  - 0006-3592
CY  - New York, NY [u.a.]
PB  - Wiley
M1  - PreJuSER-49745
SP  - 494 - 501
PY  - 2005
N1  - Record converted from VDB: 12.11.2012
AB  - This study was focused on the optimization of a new fermentation process for continuous gluconic acid production by the isolated yeast-like strain Aureobasidium pullulans DSM 7085 (isolate 70). Operational fermentation parameters were optimized in chemostat cultures, using a defined glucose medium. Different optima were found for growth and gluconic acid production for each set of operation parameters. Highest productivity was recorded at pH values between 6.5 and 7.0 and temperatures between 29 and 31 degrees C. A gluconic acid concentration higher than 230 g/L was continuously produced at residence times of 12 h. A steady state extracellular gluconic acid concentration of 234 g/L was measured at pH 6.5. 122% air saturation yielded the highest volumetric productivity and product concentration. The biomass-specific productivity increased steadily upon raising air saturation. An intracellular gluconic acid concentration of about 159 g/L (0.83 mol) was determined at 31 degrees C. This is to be compared with an extracellular concentration of 223 g/L (1.16 mol), which indicates the possible existence of an active transport system for gluconic acid secretion, or the presence of extracellular glucose oxidizing enzymes. The new process provides significant advantages over the traditional discontinuous fungi operations. The process control becomes easier, thus offering stable product quality and quantity.
KW  - Ascomycota: enzymology
KW  - Ascomycota: physiology
KW  - Bioreactors
KW  - Fermentation
KW  - Gluconates: metabolism
KW  - Hot Temperature
KW  - Humidity
KW  - Hydrogen-Ion Concentration
KW  - Microbiological Techniques: methods
KW  - Oxidation-Reduction
KW  - Oxygen: metabolism
KW  - Gluconates (NLM Chemicals)
KW  - gluconic acid (NLM Chemicals)
KW  - Oxygen (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:15937884
UR  - <Go to ISI:>//WOS:000230915400012
DO  - DOI:10.1002/bit.20533
UR  - https://juser.fz-juelich.de/record/49745
ER  -