Patent ID: 7273734

Claim:
A process for producing a polyester comprising at least one repeating unit represented by the formula: O—CH(R)—C(O) , the process comprising the steps of: (1) fermenting a saccharide with a microorganism, which is capable of forming a substituted α-hydroxy acid from the saccharide, to obtain at least one substituted α-hydroxy acid represented by the formula: HO—CH(R)—C(O)OH, wherein R represents a hydrocarbon group having 1 to 10 carbon atoms; (2) dehydrating the substituted α-hydroxy acid by two molecules to effect cyclic diesterification to obtain a cyclic dimer lactide; and (3) polymerizing the cyclic dimer lactide to produce the polyester, wherein the microorganism is an anaerobic bacterium belonging to a genus Clostridium.