Abstract
Grapefruit peel oil (GPO) contains numerous coumarins and furanocoumarins, many of which are uncharacterized. In this study, seven furanocoumarins (FC) and three coumarins were isolated from GPO by silica gel chromatography, preparative TLC, and reversed-phase HPLC. Mass spectral analyses of the FCs showed that these compounds were complex derivatives of bergaptol (5-hydroxypsoralen), the majority of which contained variously substituted geranyl side chains. The three coumarins isolated in this study also contained substituted geranyl side chains. Analyses by Fourier transform infrared (FTIR) spectroscopy provided further information about the functional groups of the compounds isolated in this study.