Beyond the whole fruit: fraction-specific chemical and metabolomic profiling of Passiflora tenuifila Killip.

Passiflora tenuifila Killip is an underexplored Brazilian native passion fruit with nutritional, phytochemical, and biological potential. However, the contribution of its structural fractions to the whole-fruit chemical profile remains poorly understood. This study characterized the chemical composition, total phenolic content, and antioxidant activity, as well as primary and specialized metabolites from whole P. tenuifila fruit and its peel, pulp, and seed fractions using spectrometric techniques combined with chemometric methods. The fractions showed marked chemical differentiation. Seeds had the highest lipid and protein contents, reaching 23.75% and 13.76%, respectively, and the strongest in vitro antioxidant response, with 67.35 μmol TE/g for ABTS, 1508.59 mg GAE/100 g for TPC, and the lowest DPPH EC50. The peel was mainly associated with carbohydrates and ash, with 81.56% and 7.98%, respectively, as well as organic acids and several flavonoid derivatives. Pulp showed a more hydrophilic profile, with the highest residual moisture content and a stronger association with soluble primary metabolites. 1H NMR-based profiling revealed fraction-dependent differences in sugars, organic acids, amino acids, choline, and fatty acid-related signals. UPLC-QToF-MS profiling revealed a differential distribution of organic acids, phenolic acids, flavonoid C-glycosides, and quercetin, luteolin, apigenin, and chrysin derivatives. PCA accounted for 95.8%, 97.5%, and 80.7% of the total variance in the composition/antioxidant, NMR, and UPLC-QToF-MS datasets, respectively. The integrated heatmap showed that the whole fruit was chemically closer to the peel than to the pulp or seed. These findings support fraction-level valorization of P. tenuifila, especially peel and seeds, for functional ingredient and high-value food applications.