Glycolic Acid → Glyoxylic Acid

Participants

Reaction Conditions

Reaction Steps

A 300-mL EZE-Seal stirred autoclave reactor equipped with Dispersimax Impeller (Autoclave Engineers) was charged with 100 mL of a solution containing glycolic acid (0.750M), ethylenediamine (0.863M), isobutyric acid (0.100M, HPLC internal standard), and flavin mononucleotide (0.01 mM), at pH 9.3, and the solution cooled to 5° C. To the reactor was then added 11.9 g of Hansenula polymorpha transformant strain GO1 (100 IU glycolate oxidase and 998,000 IU catalase) which had been permeabilized by treatment with 0.1% Triton X-100/1 freeze-thaw, and the reactor purged with oxygen. The mixture was then stirred at 500 rpm, and oxygen was bubbled through the mixture at 100 mL/min using a sparge tube located below the surface of the reaction mixture. The reaction was monitored by taking a 0.40 mL aliquot of the reaction mixture at regular intervals, filtering the aliquot using a Millipore Ultrafree-MC 10,000 NMWL Filter Unit, and analyzing the filtrate by HPLC. After 2.25 h, the yields of glyoxylic acid, oxalic acid, and formic acid were 100%, 0%, and 0%, respectively, with no glycolic acid remaining. The recovered activities of permeabilized-cell glycolate oxidase and catalase were 158% and 82% of their initial values, respectively.

Provenance & Evidence