Identification of carotenoids using mass spectrometry

Abstract

The present review compiles positive MS fragmentation data of selected carotenoids obtained using various ionization techniques and matrices. In addition, new experimental data from the analysis of carotenoids in transgenic maize and rice callus are provided. Several carotenes and oxygen-functionalized carotenoids containing epoxy, hydroxyl, and ketone groups were ionized by atmospheric pressure chemical ionization (APCI)-tandem mass spectrometry (MS/MS) in positive ion mode. Thus, on the basis of the information obtained from the literature and our own experiments, we identified characteristic carotenoid ions that can be associated to functional groups in the structures of these compounds. In addition, pigments with a very similar structure were differentiated through comparison of the intensities of their fragments. The data provide a basis for the structural elucidation of carotenoids by mass spectrometry (MS).

We thank Chao Bai, Drs. Changfu Zhu and Gemma Farré (PVCF, Universitat de Lleida, Spain) for providing plant material and the Comissionat per a Universitats i Recerca del DIUE de la Generalitat de Catalunya (Barcelona, Spain) and to the European Social Fund (ESF) for the PhD fellowship of Sol M. Rivera. This work was supported by the University of Lleida, Ministry of Science and Innovation (MICINN), Spain (BFU200761413 and CTQ2009-14699-C02-01) and an ERC Advanced Grant (BIOFORCE) to Paul Christou.