Isolation and identification of some flavanone rutinosides of the grapefruit

The 7-β-rutinosides of the flavanones naringenin, hesperetin, and isosakuranetin were isolated and identified from the segments of Texas Ruby Red grapefruit. These compounds, which are tasteless, are isomers of three bitter neohesperidosides (naringin, neohesperidin, and ponoirin) previously known to be present in grapefruit. Separation of the isomeric rutinoside and neohesperidoside pairs was accomplished by polyvinylpyrrolidone column and polyamide thin-layer chromatography.