Application of Scale-Up Criterion of Constant Oxygen Mass Transfer Coefficient (kLa) for Production of Itaconic Acid in a 50 L Pilot-Scale Fermentor by Fungal Cells of Aspergillus terreus

• Published in: Journal of microbiology and biotechnology Vol. 23; no. 10; pp. 1445 - 1453
• Main Authors: SHIN, Woo-Shik, DOHOON LEE, SANGYONG KIM, JEONG, Yong-Seob, CHUN, Gie-Taek
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society for Applied Microbiology 01.10.2013; 한국미생물·생명공학회
• Subjects: Aspergillus - growth & development; Aspergillus - metabolism; Biological and medical sciences; Bioreactors; Bioreactors - microbiology; Biotechnology; Biotechnology - methods; Fundamental and applied biological sciences. Psychology; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; Oxygen - metabolism; Succinates - metabolism; Various methods and equipments; 생물학; a; oxygen mass transfer rate coefficient (k; Fermenter; Oxygen transfer; scale-up; Fermentation; Mass transfer; Pilot plant scale; Dimensioning; Fungi; itaconic acid; Bioreactor; Production; Fungi Imperfecti; Aspergillus terreus; Application; fungal fermentation
• ISSN: 1017-7825; 1738-8872
• DOI: 10.4014/jmb.1307.07084

The scale-up criterion of constant oxygen mass transfer coefficient (kLa) was applied for the production of itaconic acid (IA) in a 50 L pilot-scale fermentor by the fungal cells of Aspergillus terreus. Various operating conditions were examined to collect as many kLa data as possible by adjusting the stirring speed and aeration rate in both 5 L and 50 L fermentor systems. In the fermentations performed with the 5 L fermentor, the highest IA production was obtained under the operating conditions of 200 rpm and 1.5 vvm. Accordingly, we intended to find out parallel agitation and aeration rates in the 50 L fermentor system, under which the kLa value measured was almost identical to that (0.02 sec(-1)) of the 5 L system. The conditions of 180 rpm and 0.5 vvm in the 50 L system turned out to be optimal for providing almost the same volumetric amount of dissolved oxygen (DO) into the fermentor, without causing shear damage to the producing cells due to excessive agitation. Practically identical fermentation physiologies were observed in both fermentations performed under those respective operating conditions, as demonstrated by nearly the same values of volumetric (Qp) and specific (qp) IA production rates, IA production yield (Yp/s), and specific growth rate (μ). Specifically, the negligible difference of the specific growth rate (μ) between the two cultures (i.e., 0.029 h(-1) vs. 0.031 h(-1)) was notable, considering the fact that μ normally has a significant influence on qp in the biosynthesis of secondary metabolites such as itaconic acid.