Study on the Metabolites of a Bacteria Strain Producing Esterifying Synthetase

摘要

The metabolites characteristics of a bacteria producing esterifying synthetase in different fermentation conditions were studied. A bacteria strain producing esterifying enzyme was isolated from Luzhou-flavor Daqu and it was identified by Biolog Microbes automated identification System. Fermentation conditions such as fermentation time, fermentation initial pH and fermentation temperature were changed. The fermentatiom broth was extracted by ethanol and analyzed by GC-MS. The results showed that the strain was Geobacillus thermoglucosidasius. With the prolonging of fermentation time, methanol and various higher alcohols were gradually decreased and even disappeared, but the esters were gradually increased. With the rise of fermentation initial pH, the acids were decreased. When initial pH was 7.5, more esters were produced, but some metabolites were not changed with the initial pH of fermentation, such as acetic acid, acetaldehyde, 3-methyl butanol and 3-Hydroxy-2-butanone etc. With the increase of fermentation temperature, the alcohols and acids kinds increased. When the fermentation temperature was 35°C, the more esters were produced.