Glycolic Acid → Glyoxylic Acid

Participants

Reaction Conditions

Reaction Steps

Into a 2.5-cm ID×20 cm glass column equipped with a 20-μm polyethylene bed support was placed 10 mL of a solution containing glycolic acid (0.25M), ethylenediamine (0.33M), propionic acid (0.075M, HPLC internal standard), and flavin mononucleotide (0.2 mM). The column and its contents were cooled to 15° C., then 2.5 IU of spinach glycolate oxidase and 27,000 IU of Aspergillus niger catalase (co-immobilized on Eupergit C) were added to the solution. Oxygen was then passed through the porous bed support and bubbled through the reaction mixture at a rate of 10 mL/min. The reaction was monitored by taking a 100 μL aliquot of the reaction mixture at regular intervals, mixing the aliquot with 300 μL of 0.1N sulfuric acid to quench the reaction, filtering the aliquot and analyzing by HPLC. After 5.5 hours, the yields of glyoxylic acid, oxalic acid, and formic acid were 98%, 2%, and 0%, respectively, with complete conversion of glycolic acid. The final activities of glycolate oxidase and catalase were 95% and 65% of their initial values.

Provenance & Evidence