Biotechnological production of D-glyceric acid and its application.

Glycerol is currently produced in large amounts as a by-product during fat splitting and biodiesel fuel production. Over the past decade, both chemical and biotechnological processes to convert glycerol to value-added chemicals have been increasingly explored. This mini-review provides recent information about the biotechnological production of a glycerol derivative, D-glyceric acid (D-GA), and its possible applications. Little is known about GA as a bioproduct, but it is naturally found in different kinds of plants as a phytochemical constituent and is reported to have some biological activity. A racemic mixture of DL-GA can be obtained from glycerol via chemical oxidation; however, D-GA is mainly biotechnologically produced with the aid of bacteria. Under aerobic conditions, some acetic acid bacteria transform glycerol into D-GA, and optimization of initial glycerol concentration and aeration rate provided a yield of more than 80 g/l D-GA, using a strain of Gluconobacter frateurii.