Proline derivatives in fruits of bergamot (Citrus bergamia Risso et Poit): presence of N-methyl-L-proline and 4-hydroxy-L-prolinebetaine.
The content of proline and various compounds deriving from its metabolism (4-hydroxy-L-proline, N-methyl-L-proline, N,N-dimethylproline, and 4-hydroxy-L-prolinebetaine) was determined in fruits and seeds of Bergamot (Citrus bergamia Risso et Poit), growing in the Calabria region (South Italy). A HPLC-ESI-tandem mass spectrometry method, which allowed rapid determination of L-proline, 4-hydroxy-L-proline, N-methyl-L-proline, N,N-dimethylproline, and 4-hydroxy-L-prolinebetaine in juice and extracts of bergamot fruit with minimum sample preparation and short analysis time (about 10 min), is presented. Proline and 4-hydroxy-L-proline levels in the samples were also determined by HPLC analysis with fluorescence detection and the results compared to those obtained with HPLC-ESI-tandem mass spectrometry. For the first time, the presence of N-methyl-L-proline and 4-hydroxy-L-prolinebetaine in the fruits of a plant of the Citrus genus is reported.
Dipartimento di Biochimica e Biofisica, II Università degli Studi di Napoli, Naples, Italy. luigi.servillo@unina2.it
Luigi
L
Servillo
Alfonso
A
Giovane
Maria Luisa
ML
Balestrieri
Domenico
D
Cautela
Domenico
D
Castaldo
D002957:Citrus / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry*; D010936:Plant Extracts / Q000032:analysis*; D011392:Proline / Q000031:analogs & derivatives / Q000032:analysis*
D010936:Plant Extracts; D011392:Proline