Kinetic Analysis of Kluyveromyces Marxianus Yeast Strain
This research investigated the growth kinetic parameters (Ks and µmax) of the Kluyveromyces marxianus yeast strain for a batch process under aerobic and anaerobic conditions at 45oC using the Two-Liter Bioflo® 2000 Fermentors and the Orbital Shaker Bed with 250mL flasks (New Brunswick Scientific). This yeast strain was grown in twelve different glucose media concentrations (Anderson et al. 1986), ranging from 200 mg/L to 80,000 mg/L. Several analytical techniques were used, such as COD measurement to determine soluble and total substrate concentrations, TSS and OD measurements to determine biomass formation, HPLC measurements to determine carbohydrate concentrations, and GC measurements to determine alcohol concentrations. The growth kinetic parameters were investigated using the Monod Model which accounts for microbial growth in any environmental condition, assuming decay a constant for the microorganism negligible during the exponential growth phase. The nonlinear (the Lee equation) and linear (the Hanes and the Lineweaver-Burk equations) methods were used to estimate the kinetic parameters (Ks and µmax) for the aerobic and the anaerobic conditions. Neither the nonlinear nor the linear method succeeded with reasonable estimations for the growth kinetic parameters (Ks and µmax). The lack of information and investigation on the nonlinear and the linear models in the literature, concerning Kluyveromyces marxianus kinetic analysis initiated an investigation of these nonlinear and linear models using a mathematical simulation technique called the Monte Carlo method with the SAS (Statistical Analysis Software) program (version 9). The sweet potato waste was used as substrate for a preliminary experiment which was designed to determine the growth kinetic parameters at 40oC, 45oC, and 50oC and the Arrhenius parameters for the Kluyveromyces marxianus yeast strain (Appendix A). This preliminary experiment used the three Two-Liter Bioflo® 2000 fermentors (New Brunswick Scientific) for a batch process under anaerobic conditions.
Advisor:James Geaghan; Terry Walker; Caye Drapcho
School:Louisiana State University in Shreveport
School Location:USA - Louisiana
Source Type:Master's Thesis
Keywords:biological agricultural engineering
Date of Publication:04/16/2004