Resolution of 1,2-epoxyoctane by enantioselective catalytic hydrolysis in a membrane bioreactor

A flow-through membrane bioreactor was developed for the enantioselective catalytic hydrolysis of racemic 1,2-epoxyoctane (epoxide) to (S)-1,2-epoxyoctane and (R)-1,2-octanediol by an enzyme from the yeast Rhodosporidium toruloides. The effect of the low solubility on access of the epoxide to the yeast cells was improved by adding 20% ethanol (EtOH) to the aqueous buffer in the feed. Two process parameters were investigated to improve selectivity. The separation factor of the racemic epoxide (αepoxide) was increased from 2.3 to 6.3 by breaking the yeast cells. While the influence of the amount of yeast cells on selectivity was negligible, decreasing the flow rate from 0.4 to 0.2 ml min−1 resulted in an increase of αepoxide from 4.4 to 17.7.