engleski

An integrated bioprocess for production and recovery of lactic acid

Strain Lactobacillus amylovorus DSM 20531T belongs to the ALAB and its ability to perform simultaneous semi-solid substrate saccharification and fermentation (s5f) of polymeric carbohydrates to lactic acid at relatively low temperatures and pH values has been successfully demonstrated in the laboratory scale (up to 80 L, unpublished data). So, the first part of the problem has been solved and a feasible downstream procedure of s5f-derived lactic acid has to be adapted to it. We would like to investigate possibilities for subsequent esterification of the s5f- derived lactic acid to a volatile ester. Alcohol production by another biocatalyst, e.g. a wild-type or a genetically engineered Saccharomyces cerevisiae strain, could be coupled to the s5f in order to perform the esterification. Separation of the two production bioprocesses, the s5f and the alcohol production, from the esterification could be achieved by encapsulation of the two biocatalysts. Since mechanical stability and other desirable properties of certain encapsulation polymers is reduced under above conditions, modified versions of easily available encapsulation polymers should be used in this integrated bioprocess (1, 2). Our main intention is to develop an integrated bioprocess consisted of the s5f production and recovery of the s5f-derived lactic acid in a collaboration with an industrial partner. Hence, advanced s5f paired with the alcohol production, both catalysed by encapsulated biocatalysts, might lead to a lactic acid esterification and therefrom in situ removal of formed lactate ester. Such progressive integrated bioprocess should provide more than several advantages over conventional bioprocesses and significantly reduce current price of lactic acid as a final product as well as the building block chemical.

integrated bioprocess, lactic acid, production and recovery

nije evidentirano