Comprehensive Quality Analysis and Exploration of Xanthine Oxidase Inhibitory Activity of 30 Crabapple Varieties

To elucidate the quality characteristics of crabapple cultivars and facilitate resource utilization, we systematically evaluated 30 crabapple varieties using multidimensional analyses. Physicochemical parameters (fruit weight, moisture content, and soluble solids content) and bioactive profiles (xanthine oxidase inhibitory activity, expressed as IC50) were quantified. Antioxidant potential was assessed using three established methods: DPPH and ABTS+ radical scavenging capacity, and ferric ion-reducing antioxidant power. Multivariate statistical approaches, including correlation analysis, principal component analysis (PCA), and hierarchical cluster analysis, were used for data interpretation. Notably, the cultivars contained substantial levels of total phenolics (2.749~80.877 mg GAE/g DW) and flavonoids (3.522~167.312 mg RE/g DW), demonstrating strong negative correlations (P50=2.724 mg/mL). Despite the suboptimal sugar–acid ratio (0.47~5.48), these findings position crabapples as valuable raw materials for functional food processing (such as juice and wine production) and natural bioactive compound extraction. This study establishes a scientific framework for the comprehensive quality assessment of crabapple resources, providing critical insights for varietal selection in nutraceutical development and value-added processing.