Improved extraction and reversed phase‐high performance liquid chromatographic separation of flavonoids and the identification of Rosa cultivars

Optimal extraction methods and Reversed‐Phase High Performance Liquid Chromatographic (RP‐HPLC) procedures were developed for the isolation and resolution of naturally occurring flavonoids and related phenolic compounds in Rosa petals. The following flavonoids and related phenolics were identified or partly identified: cyanidin 3, 5‐di‐ O ‐glucoside; cyanidin 3, 5‐di‐ O ‐glycoside (sugar moieties, glucose and arabinose); pelargonidin 3, 5‐di‐ O ‐glycoside; pelargonidin 3‐ O ‐glycoside; quercetin 3‐ O ‐glucoside; ellagic acid; quercetin 3‐ O ‐arabinoside; quercetin 4′‐ O ‐glucoside; kaempferol 4′‐ O ‐glucoside; kaempferol 3‐ O ‐rutinoside; kaempferol 3‐ O ‐glycoside; kaempferol 3‐ O ‐arabinoside; kaempferol 3‐ O ‐rhamnoside and kaempferol 3‐ O ‐glycoside. Significant qualitative and quantitative differences between the above flavonoid markers allowed an objective distinction between 44 cultivars examined. The production of ‘Flower Flavonoid RP‐HPLC Fingerprints’, which have been converted in the corresponding ‘Computer Flower Flavonoid Identity Cards’ via a suitable computer program, has proven to be of great value for Rosa cultivar recognition.