Metabolomics Analysis of Different Varieties of Pouteria caimito Fruit Based on UHPLC-MS/MS

To investigate the differences in pulp metabolites among four varieties of Pouteria caimito fruit (JZL1, JZL3, JZL5, and JZL6), ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was employed for the separation and identification of metabolites. A total of 1285 metabolites were identified, including 648 in positive ion mode and 637 in negative ion mode. At the class level, carboxylic acids and derivatives (14.32%) and organooxygen compounds (11.83%) accounted for the highest proportions; at the subclass level, amino acids, peptides, and analogues (12.53%) as well as carbohydrates and carbohydrate conjugates (9.49%) were the main categories. PLS-DA analysis revealed significant differences in metabolite profiles among the four varieties, with numerous up-regulated and down-regulated metabolites in each comparison group, and some metabolites showed fold changes > 10 or <0.1. KEGG pathway enrichment analysis further indicated that differential metabolites were primarily enriched in pathways such as ABC transporters, citrate cycle (TCA cycle), starch and sucrose metabolism, and linoleic acid metabolism. This study provides an important metabolomic basis for variety identification, nutritional quality evaluation, and functional component development of Pouteria caimito fruit.