Targeted-Analysis of β-Carboline Alkaloids in Passionfruit (“Maracujá”) by SBSE(PDMS)-LC/Flu and UHPLC-MS

Samples of pulp and seeds of sour (P. edulis) and sweet (P. alata) passionfruit were subjected to targeted analysis to identify β-carboline alkaloids, using combined UHPLC-MS (ultrahigh performance liquid chromatography-mass spectrometry) and SBSE(PDMS) (stir bar sorption extraction using polydimethylsiloxane as stationary phase) for sample preconcentration. All the samples contained harmane and harmine; harmaline was found only in P. alata seeds and in P. edulis pulp, while harmalol was found only in P. alata seeds. An analysis of sweet passionfruit by SBSE(PDMS) combined with LC/Flu (liquid chromatography/fluorescence detection) indicated 1.03 × 10-1 ± 3.05 × 10-3 µg harmane L-1 pulp and 7.44 × 10-5 ± 2.55 × 10-6 µg harmane g-1 seeds, but harmine was not detectable by the quantitative method. Our findings underscore the need for further studies about passionfruit food safety, in view of the potential toxicity of β-carboline alkaloids.