A simple chiral high-performance liquid chromatographic method to study the enantiomer-differentiating action of microorganisms. An assay with DL-tryptophan.

To investigate the 'enantiomer-differentiating' action of the microorganisms colonizing a phosphate-buffered DL-tryptophan solution, a novel chiral high-performance liquid chromatographic (HPLC) arrangement was developed and established. As the HPLC stationary phase, bovine serum albumin (BSA) bonded silica gel was used. In the function of the mobile phase, phosphate-buffered DL-tryptophan solution was applied. The composition of the eluate was monitored by an HPLC spectrophotometric detector. After injecting the assayed sample into the eluent stream, the content of each tryptophan enantiomer was evaluated either from the positive or negative responses of the HPLC detector. The validity and the performance of this novel approach were confirmed by applying another chiral HPLC device working with human serum albumin (HSA) bonded silica gel as the stationary phase and with 1-propanol containing phosphate buffer as the eluent.