Glycolic Acid → Glyoxylic Acid

Participants

Reaction Conditions

Reaction Steps

A 300-mL EZE-Seal stirred autoclave reactor (Autoclave Engineers) was charged with 75 mL of a solution containing glycolic acid (0.75M), ethylenediamine (0.86M, pH 9.2), propionic acid (0.075M, HPLC internal standard), and flavin mononucleotide (0.01 mM), and the solution cooled to 15° C. To the reactor was then added 14 g of frozen (-80° C.) Aspergillus nidulans ST17SYG/OL (25.2 IU glycolate oxidase and 20,400 IU catalase), and the cells were allowed to thaw at 15° C. The resulting mixture was stirred at 400 rpm and 15° C. under 70 psig (483 kPa) of oxygen, while bubbling oxygen through the mixture at 20 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 7 hours, the yields of glyoxylic acid, oxalic acid, and formic acid were 79%, 0%, and 0%, respectively, with 2.7% recovery of glycolic acid. The final activities of glycolate oxidase and catalase were 55% and 80% of their initial values.

Provenance & Evidence