Abstract
A chromatographic method for the qualitative and quantitative characterization of
peels and preparations based on different species of Citrus was developed in order to obtain a complete profile of the constituents, including
flavonoids and protoalkaloids. Commercial peels of sweet orange, lemon, mandarin,
and grapefruit were analyzed. Seventeen constituents including flavanones, flavones,
polymethoxyflavones, and protoalkaloids were identified by HPLC-PDA, HPLC-MS, and
HPLC-MS/MS using a comparison of retention times and UV-Vis and MS spectra with reference
standards and literature data. The total amount of flavanones [neoeriocitrin (5), naringin (8) and hesperidin (9)] and polymethoxflavones [sinensetin (12), nobiletin (14), 3,5,6,7,8,3′,4′-heptamethoxyflavone (15), and tangeretin (16)] was determined and expressed as naringin (8) or hesperidin (9), and sinensetin (12), respectively. The protoalkaloid synephrine was detected in all samples, except
in grapefruit, but its content was lower than the limit of quantification. Qualitative
and quantitative chemical profiles of three different Italian aromatic liquors (“Limoncello”,
“Arancello”, and “Mandarinetto”), prepared according to traditional recipes, were
also analyzed.
Key words
Citrus peels and preparations - flavanones - flavones - polymethoxyflavones - protoalkaloids
- HPLC-PDA MS