Evaluation of Medium Components by Plackett-Burman Statistical Design for Lipase Production by Candida rugosa and Kinetic Modeling

Lipase production by Candida rugosa was carried out in submerged fermentation. Plackett-Burman statistical experimental design was applied to evaluate the fermentation medium components. The effect of 12 medium components was studied in 16 experimental trials. Glucose, olive oil, peptone and FeCl3·6H2O were found to have more significance on lipase production by Candida rugosa. Maximum lipase activity of 3.8 u/mL was obtained at 50 h of fermentation period. The fermentation was carried out at optimized temperature of 30°C, initial pH of 6.8 and shaking speed of 120 rpm. Unstructured kinetic models were used to simulate the experimental data. Logistic model, Luedeking-Piret model and modified Luedeking-Piret model were found suitable to efficiently predict the cell mass, lipase production and glucose consumption, respectively with high determination coefficient (R2). From the estimated values of the Luedeking-Piret kinetic model parameters, α and β, it was found that the lipase production by Candida rugosa is growth associated.