Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.
2006
Volume 9
Issue 1
Topic:
Biotechnology
ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
Rymowicz W. , Cibis E. 2006. OPTIMIZATION OF CITRIC ACID PRODUCTION FROM GLUCOSE SYRUP BY YARROWIA LIPOLYTICA USING RESPONSE SURFACE METHODOLOGY, EJPAU 9(1), #20.
Available Online: http://www.ejpau.media.pl/volume9/issue1/abs-20.html

OPTIMIZATION OF CITRIC ACID PRODUCTION FROM GLUCOSE SYRUP BY YARROWIA LIPOLYTICA USING RESPONSE SURFACE METHODOLOGY

Waldemar Rymowicz1, Edmund Cibis2
1 Department of Biotechnology and Food Microbiology, Wroc│aw University of Environmental and Life Sciences, Poland
2 Department of Bioprocess Engineering, Wroc│aw University of Economics, Poland

 

ABSTRACT



A new criterion was proposed to evaluate the process of citric acid biosynthesis by the acetate negative mutant strain Yarrowia lipolytica AWG-7 cultivated on glucose syrup by the repeated-batch method. This criterion imparts the same weight to the overall amount of the citric acid production and to the trend in citric acid concentration. To determine the optimum levels of bacto-peptone, ammonium chloride and potassium dihydrogen phosphate which maximize the proposed objective function, a central composite design was developed using 50 ml repeated-batch fermentation. The design involved 20 processes conducted with various combinations of the five values of these three parameters. The experiments produced empirical values of the proposed criterion which were then approximated with the fourth-order polynomial. It was found that the optimal concentrations of bacto-peptone, ammonium chloride, and potassium dihydrogen phosphate equaled 8.5; 159.8 and 65 mgl-1, respectively.

Key words: Yarrowia lipolytica, glucose syrup, citric acid, response surface methodology, acetate negative mutant.


Waldemar Rymowicz
Department of Biotechnology and Food Microbiology,
Wroc│aw University of Environmental and Life Sciences, Poland
Norwida 25, 50-373 Wroclaw, Poland
Fax. 48-71-3284124
Phone: 48-71-3205143
email: rymowicz@ozi.ar.wroc.pl

Edmund Cibis
Department of Bioprocess Engineering,
Wroc│aw University of Economics, Poland
Komandorska 118/120, 53-345 Wroc│aw, Poland

Responses to this article, comments are invited and should be submitted within three months of the publication of the article. If accepted for publication, they will be published in the chapter headed 'Discussions' and hyperlinked to the article.