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 9.25, and the solution cooled to 5° C. To the reactor was then added 2.0 g of Pichia pastoris transformant strain GS115-MSP10 (2763 IU glycolate oxidase and 494,000 IU catalase) which had been permeabilized by treatment with 0.1% Triton X-100/6 freeze-thaws, and the reactor purged with oxygen. The mixture was then stirred at 1000 rpm, which bubbled oxygen through the mixture via the action of the turbine impeller, and at 5° C. under 120 psig of oxygen. The reaction was monitored by taking a 0.4 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 0.75 h, the yields of glyoxylic acid, oxalic acid, and formic acid were 99.1%, 0.3%, and 0%, respectively, with 0.6% glycolic acid remaining. The recovered activities of permeabilized-cell glycolate oxidase and catalase were 104% and 105% of their initial values, respectively.

Provenance & Evidence