Separation of the enantiomers of naringenin and eriodictyol by amylose-based chiral reversed-phase high-performance liquid chromatography.

Naringenin and eriodictyol are chiral flavanones widely present in citrus fruits and herbal products. Pharmacological interest in the two flavanones is well known. Due to the chiral carbon atom, the compounds always exist in the racemic form. The present study reported a stereospecific HPLC method for the enantioseparation of naringenin and eriodictyol, which was performed on an amylase-based chiral stationary phase (CSP), Chiralpak AD-RH, in the reversed-phase mode. The effects of the mobile phase on retention, enantioseparation, and elution order were investigated. The different 3',4' substituent pattern of the two compounds affected the enantioselectivity. An online coupling HPLC-CD method was used for elution order determination. Both the CD sign of the eluted peaks at a single wavelength and complete CD spectra of the eluted enantiomers were obtained by the method.