Glycerol carbonate butyrate

Important results have recently been obtained by Simon. Among other things he ascertained that glycerol yields butyric acid. The formation of four-carbon compounds from six-carbon substrates is independent of the grouping (aldehyde, hydroxyl, carboxyl, phosphory-lated hydroxyl) at the first carbon atom of the molecule. L-Rhamnose and D-arabitol are fermented, but not n-arabinose and D-sorbitol. In contrast to the studies of Underkofler and Hunter, " L-sorbose has been found fermentable. Results obtained with fresh and acetone-dried Cl. hutylicum are identical in principle. 

More than seventy years ago the impressive discovery was made that bioreduction of mannitol, glycerol and starch yields butanol. Fermentations in which butyric acid, butanol and acetone are formed from carbohydrates by different bacilli (butyl bacteria) belong in this group. The term butyl bacteria as a generic name for microbes producing the genetically related substances of the four-carbon series was proposed in 1921" and has been applied since then. The approximate course of these reactions is shown by the following formulations which, however, do not explain the mechanism ... 

Acetic acid Acetaldehyde Acetone L-Alanine l-Alanine ion L-Alaninate ion L-Arginine dl-Aspartic acid L-Aspartic acid L-Aspartic acid ion L-Aspartate ion Benzene Butyric acid Butyrate ion Carbon dioxide Citric acid Citrate ion Creatine L-Cysteine L-Cystine Ethanol Ethyl acetate Formic acid Formate ion Fumaric acid Fumarate ion a-D-Glucose p-D-Glucose Glycerol L-Glutamic acid L-Glutamate ion... 

Fatty acids are long chained carboxylic acids. Most of the carboxylic acids in the fatty acids fraction are found as esters of glycerol. The simplest member of the fatty acids is butyric acid, this has four carbon atoms. (C3H7COOH). 

Also, the average carbon isotope contents of a series of glycerol samples have been determined. The results indicated that it is possible to distinguish the glycerol obtained from the glycerides produced in plants following the C-3 and C-4 carbon fixation pathways (104). Natural ethyl butyrate can be differentiated from industrial manufactured ethyl butyrate by the content of (105). 

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