Showing papers on "2,3-Butanediol published in 1997"
TL;DR: A simple and effective method of treatment of lignocellulosic material was used for the preparation of corn cob for the production of 2,3-butanediol by Klebsiella oxytoca ATCC 8724 in a simultaneous saccharification and fermentation process.
Abstract: A simple and effective method of treatment of lignocellulosic material was used for the preparation of corn cob for the production of 2,3-butanediol by Klebsiella oxytoca ATCC 8724 in a simultaneous saccharification and fermentation process. During the treatment, lignin, and alkaline extractives were solubilized and separated from cellulose and hemicellulose fractions by dilute ammonia (10%) steeping. Hemicellulose was then hydrolyzed by dilute hydrochloric acid (1%, wJv) hydrolysis at 100 degrees C at atmospheric pressure and separated from cellulose fraction. The remaining solid, with 90% of cellulose, was then used as the substrate. A butanediol concentration of 25 g/L and an ethanol concentration of 7 g/L were produced by K. oxytoca from 80 g/L of corn cob cellulose with a cellulase dosage of 8.5 IFPU/g corn cob cellulose after 72 h of SSF. With only dilute acid hydrolysis, a butanediol production rate of 0.21 g/L/h was obtained that is much lower than the case in which corn cob was treated with ammonia steeping prior to acid hydrolysis. The butanediol production rate for the latter was 0.36 g/L/h.
74 citations
TL;DR: A gene fragment including genes coding for three enzymes involved in the formation of meso-BD of K. pneumoniae IAM 1063 forms 2,3-butanediol consisting of a mixture of the meso - and l -isomers from glucose.
53 citations
TL;DR: In this article, a number of strains of Lactobacillus spp. from foods were screened for their ability to convert meso-2,3-butanediol into 2-butanol.
Abstract: A number of strains of Lactobacillus spp. from foods were screened for their ability to convert meso-2,3-butanediol into 2-butanol. Only three strains of L. brevis transformed the meso-diol into the secondary alcohol. These strains as well as the others unable to metabolize meso-2,3-butanediol exhibited the capacity to hydrogenate 2-butanone to 2-butanol. In both types of lactobacilli, an inverse relationship was observed between the diol or ketone concentration and the abundance of the R form of 2-butanol. This fact has been interpreted in terms of a co-occurrence of two dehydrogenases, both acting on the ketone with different kinetic parameters and opposite enantioselectivities. These results represent a further support to the assumption that 2-butanol present in distillates originates from the enzymatic activity of lactobacilli growing on mashes and give the most likely explanation of the enantiomeric excess of (R)-2-butanol generally found in distillates. Keywords: 2-Butanol; meso-2,3-butanediol; lact...
34 citations