Comparison and analysis of four Citrus aurantium varieties used in Aurantii Fructus in terms of chemical profiles

Aurantii Fructus (AF), the dried unripe fruit of Citrus aurantium L., is a widely used food-medicine homology resource with valued nutritional and bioactive properties. As a member of the genus Citrus, AF has multiple cultivated varieties, but systematic phytochemical profiling of distinct AF varieties remains insufficient, hindering accurate quality evaluation and rational utilization. This study aimed to characterize the chemical profiles of four cultivated AF varieties: C. aurantium 'Xiucheng', C. aurantium 'Chuan', C. aurantium 'Daidai', and C. aurantium 'Huangpi'. An integrated analytical platform combining UPLC-Q-Exactive Orbitrap-MS and GC-MS was used to identify 129 non-volatile and 62 volatile compounds. Multivariate analysis revealed 15 non-volatile and 11 volatile markers for variety discrimination. UPLC quantitative analysis of 17 major differential components revealed distinct accumulation patterns: all varieties were high in naringin and neohesperidin; C. aurantium 'Daidai' had elevated vicenin II, neoeriocitrin, and luteolin; C. aurantium 'Xiucheng' and C. aurantium 'Huangpi' were rich in narirutin and meranzin hydrate; C. aurantium 'Huangpi' had the highest hesperidin content. These findings confirm significant inter-variety chemical variations, provide theoretical support for AF’s application in pharmaceuticals and functional foods, and lay a scientific basis for variety authentication and quality evaluation. • Systematic comparative analysis of chemical compositions in four botanically distinct Aurantii Fructus (AF) variants for food and medicinal applications. • An integrated UPLC-Q-Exactive Orbitrap-MS and GC-MS approach systematically characterized the chemical profiles of four Aurantii Fructus varieties.A total of 129 non-volatile and 62 volatile compounds were identified in AF, providing a comprehensive phytochemical database for this food-medicine homolog. • Chemometric-assisted (heatmap/PCA) authentication of AF variants based on characteristic chemical fingerprints • Results from the quantitative analysis of 17 marker components revealed significant differences in the accumulation patterns of major bioactive compounds (e.g., naringin, neohesperidin, hesperidin) among the four Aurantii Fructus varieties. • This study confirms significant inter-variety chemical variations of AF, laying a scientific basis for its quality evaluation, geographical authentication, and rational utilization in pharmaceuticals and functional foods.