Changes in the composition of the polar fraction of Persian lime (Citrus latifolia) during fruit growth by LC-QTOF MS/MS analysis

- Changes in global composition of polar Persian lime metabolites during maturation.
- Differentiation among samples based on untargeted analysis.
- Changes in the relative concentration of major polar metabolites during fruit growth.
- MS/MS-based tentative identification of 72 metabolites.
- Confirmed identification by standards of 19 metabolites.

Citrus possess a large number of bioactive compounds mainly studied in ripe fruits. Few studies have focused on evolution of metabolites during fruit growth. In this study, fruits were sampled from weeks 1-14 of the ripening process. Polar extracts were obtained from all collected samples and analysed by liquid chromatography-tandem mass spectrometry. Analysis of variance applied to the dataset indicated that the relative concentration of 394 out of 423 molecular entities changed significantly during maturation. Principal component analysis showed a clear separation among samples from different weeks and revealed the main compounds responsible for differentiation. Additionally, 72 metabolites were tentatively identified and changes in their relative concentration during growth were individually analysed. The observed trends in relative concentrations of representative metabolites during the growth process are discussed.