Isolation of codeine and norcodeine from microbial transformation liquors by preparative high-performance liquid chromatography

Abstract

Codeine and norcodeine have been extracted together from a 7-l batch of microbial transformation liquor using an XAD-4 resin column. The extract was divided equally and used to compare normal-phase (NP) and reversed-phase (RP) preparative high-performance liquid chromatography for the recovery of pure codeine and norcodeine. The conditions for each column were optimised for maximum sample throughput with complete resolution of both compounds. The aqueous fractions of codeine and norcodeine from the RP column were also passed through an XAD-4 resin column to extract the compounds finally, whereas the organic solvent fractions from the NP column did not require this step. The RP procedure gave recoveries of 71.25% of codeine (98.6% purity) and 80.69% of norcodeine (97.5% purity) and the NP procedure gave recoveries of 79.20% of codeine (96.7% purity) and 83.97% of norcodeine (97.2% purity). Owing to its superior sample throughput and lower operating costs, the RP procedure is recommmended for routine use.