Enhanced Acetone, Butanol, and Ethanol Fermentation by Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564) in a Chemically Defined Medium: Effect of Iron and Initial pH on ABE Ratio

HANIES AMBARSARI AMBARSARI; KENJI SONOMOTO

doi:10.5454/mi.6.4.1

Authors

HANIES AMBARSARI AMBARSARI Institute of Environmental Technology (BTL) â€“ Indonesian Agency for Assessment and Application of Technology (BPPT), Building 412 PUSPIPTEK Serpong, Banten 15314, Indonesia
KENJI SONOMOTO Laboratory of Microbial Technology, Division of Microbial Science and Technology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan Laboratory of Functional Food Design, Department of Functional Metabolic Design, Bio-Architecture Center, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan

DOI:

https://doi.org/10.5454/mi.6.4.1

Keywords:

acetone-butanol-ethanol (ABE), Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564), glucose, initial pH, iron, TYA medium

Abstract

Batch studies were performed to investigate the performance of Clostridium saccharoperbutylacetonicum N1-4 (ATCC 13564) in acetone-butanol-ethanol (ABE) fermentation as affected by iron and initial pH in defined TYA (Tryptone-Yeast extract-Acetate) media. Different concentrations of FeSO₄.7H₂O in the TYA media were found to influence the ABE fermentation process resulting in different ABE ratios. From the experiment with different concentrations of FeSO₄.7H₂O, it was also found that lag phases at initial pH of 4.4 were longer than those at initial pH of 6.5, however they could still have higher ABE productivity values. Addition of 0.003 g L^-1 FeSO₄.7H₂O could give the highest ABE production with both initial pH of 6.5 and 4.4. With more than 0.01 g L^-1 FeSO₄.7H₂O, ratios of acetone to butanol (0.50 - 0.53) were higher at initial pH of 4.4 than those (0.26 - 0.28) at initial pH of 6.5. Those differences were not obtained with low concentration of FeSO₄.7H₂O among the same initial pH. It was also confirmed that initial pH affected ABE production significantly more than FeSO₄.7H₂O by statistical analysis.