Patent ID: 7927847

Claim:
A process for enzymatically converting glycolonitrile to glycolic acid, said process comprising: (a) providing a set of reaction components comprising: (i) an aqueous solution of glycolonitrile comprising at least 0.01 ppm formaldehyde; (ii) an enzyme catalyst comprising a polypeptide having nitrilase activity wherein said polypeptide has the amino acid sequence set forth in SEQ ID NO:53; wherein said enzyme catalyst comprises a specific activity for hydrolyzing glycolonitrile to glycolic acid; and (iii) an effective amount of at least one amine protectant selected from the group consisting of a) a compound of the formula [R 3 ] (1+X) —NH (2-X) wherein X is 0 or 1 and R 3 is independently C1 to C20 hydrocarbyl group or substituted hydrocarbyl group, wherein R 3 optionally comprises one or more ether linkages; with the proviso that (i) the substituted group is not a cyano group capable of reacting with the enzyme catalyst and (ii) R 3 is not a carbonyl group, b) a polyamine polymer comprising an effective number of free amine groups; and c) an amine-functionalized material comprising an effective number of free amine groups; wherein the amine protectant is not naturally-produced by said enzyme catalyst; (b) combining the set of reaction components under suitable aqueous reaction conditions whereby glycolic acid is produced; wherein said specific activity is increased by the addition of said at least one amine protectant; and (c) recovering the glycolic acid or salt thereof produced in (b).