Table of Contents
ISRN Microbiology
Volume 2014, Article ID 578682, 7 pages
Research Article

Comparative Assessment of Factors Involved in Acetoin Synthesis by Bacillus subtilis 168

1Department of Bioscience and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
2Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India

Received 13 January 2014; Accepted 6 February 2014; Published 10 March 2014

Academic Editors: G. Koraimann and T. P. West

Copyright © 2014 Pratibha Sharma and Santosh Noronha. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Acetoin is widely used as flavor agent and serves as a precursor for chemical synthesis. Here we focused on identifying the best physiological conditions (initial substrate concentrations, pH, temperature, and agitation) for enhanced acetoin accumulation by Bacillus subtilis 168. The optimal physiological conditions support maximum acetoin accumulation by minimizing byproduct (acetate and butanediol) synthesis and a maximum of 75% enhancement in acetoin yield could be achieved. Additionally, the effect of change in ALS (acetolactate synthase) and ALDC (acetolactate decarboxylase) activities was evaluated on acetoin accumulation. Increasing ALS and ALDC enzyme activities led to efficient utilization of pyruvate towards acetoin accumulation and about 80% enhancement in acetoin accumulation was observed.