Showing papers on "2,3-Butanediol published in 1949"

Production and properties of 2,3-butanediol: xxxii. 2,3-butanediol fermentations at poised hydrogen ion concentrations

Abstract: The anaerobic dissimilation of glucose by Bacillus polymyxa, Bacillus subtilis (Ford's type), Aerobacter aerogenes, and Serratia marcescens was studied at poised hydrogen ion concentrations covering the range pH 5.0 to 8.0. Each fermentation was controlled within ±0.05 pH units by automatic addition of ammonium hydroxide solutions. The hydrogen ion concentration had a marked effect on the overall rate of dissimilation and the relative yield of products that was similar for all organisms. The time required to completely ferment a medium containing 5% glucose varied from 22 hr. for Bacillus subtilis to for Aerobacter aerogenes at the optimum pH, which was within the range 7.0 to 7.6. The yield of 2,3-butanediol decreases above pH 6.4, until above pH 7.6 little or none is formed, although fairly rapid breakdown of glucose is still obtained. At the same time the yield of acetoin tends to increase, while there is little change in the amount of ethanol formed. The yields of acetic and lactic acids increase mark...