Use of response surface methodology in a fed-batch process for optimization of tricarboxylic acid cycle intermediates to achieve high levels of canthaxanthin from Dietzia natronolimnaea HS-1.
In this work, we applied statistical experimental design to a fed-batch process for optimization of tricarboxylic acid cycle (TCA) intermediates in order to achieve high-level production of canthaxanthin from Dietzia natronolimnaea HS-1 cultured in beet molasses. A fractional factorial design (screening test) was first conducted on five TCA cycle intermediates. Out of the five TCA cycle intermediates investigated via screening tests, alfaketoglutarate, oxaloacetate and succinate were selected based on their statistically significant (P<0.05) and positive effects on canthaxanthin production. These significant factors were optimized by means of response surface methodology (RSM) in order to achieve high-level production of canthaxanthin. The experimental results of the RSM were fitted with a second-order polynomial equation by means of a multiple regression technique to identify the relationship between canthaxanthin production and the three TCA cycle intermediates. By means of this statistical design under a fed-batch process, the optimum conditions required to achieve the highest level of canthaxanthin (13172 + or - 25 microg l(-1)) were determined as follows: alfaketoglutarate, 9.69 mM; oxaloacetate, 8.68 mM; succinate, 8.51 mM.
Department of Food Science and Engineering, Faculty of Biosystem Engineering, College of Agriculture, University of Tehran, P.O. Box 31587-78659, Karaj, Islamic Republic of Iran.
Mohammad Reza
MR
Nasri Nasrabadi
Seyed Hadi
SH
Razavi
D000192:Actinomycetales / Q000254:growth & development / Q000378:metabolism*; D019149:Bioreactors; D001709:Biotechnology; D016644:Canthaxanthin / Q000096:biosynthesis*; D002952:Citric Acid Cycle; D005285:Fermentation; D005505:Food Coloring Agents / Q000378:metabolism; D007656:Ketoglutaric Acids / Q000378:metabolism; D008954:Models, Biological; D062907:Oxaloacetic Acid / Q000378:metabolism; D019802:Succinic Acid / Q000378:metabolism
D005505:Food Coloring Agents; D007656:Ketoglutaric Acids; D062907:Oxaloacetic Acid; D016644:Canthaxanthin; D019802:Succinic Acid