Response Surface Methodology for Biobutanol Optimization Using Locally Isolated Clostridium acetobutylicum YM1

Abstract

In this study, response surface methodology (RSM) was applied to optimize and investigate the ability of yeast extract, CaCO₃, MgSO₄, and K₂HPO₄ to maximize biobutanol production by a novel local isolate of Clostridium acetobutylicum YM1. A central composite design was applied as the experimental design, and analysis of variance (ANOVA) was used to analyze the experimental data. A quadratic polynomial equation was obtained for biobutanol production by multiple regression analysis. ANOVA analysis showed that the model was significant (p < 0.0001), and the yeast extract, CaCO₃, and MgSO₄ concentrations had a significant effect on biobutanol production. However, K₂HPO₄ did not have a significant effect on biobutanol production. The estimated optimum combinations for biobutanol production using C. acetobutylicum YM1 were 2 g/L yeast extract, 6 g/L CaCO₃, 0.1 g/L MgSO₄, and 1.1 g/L K₂HPO₄. Subsequently, the model was validated through use of the estimated optimum conditions, which confirmed the model validity and 13.67 g/L of biobutanol was produced.

Keywords:

• Biobutanol
• Clostridium acetobutylicum YM1
• Medium optimization
• Response surface methodology
• Renewable energy

Additional information

Funding

This research was supported by Universiti Kebangsaan Malaysia under grants FGRS/1/2011/ST/UKM/02/2, DLP-2013-023, and DPP-2013-020.