Exploratory Analysis of Phenolic Profiles and Antioxidant Capacity in Selected Romanian Monofloral Honeys: Influence of Botanical Origin and Acquisition Source

This exploratory study assessed the influence of botanical origin and acquisition source on the phenolic profile and antioxidant properties of selected Romanian monofloral honeys. Eight samples were analyzed, representing five floral types: acacia, linden, rapeseed, lavender, and thyme. For acacia, linden, and rapeseed, both commercial and locally sourced honeys were included. Analytical techniques included total phenolic content (TPC, Folin-Ciocalteu), antioxidant assays (DPPH, ABTS, FRAP), color intensity (ABS₄₅₀), and phenolic compound profiling via HPLC-DAD-ESI⁺. TPC ranged from 179.26 ± 23.57 to 586.67 ± 18.33 mg GAE/100 g, with thyme and linden honeys presenting the highest values. Seventeen phenolic compounds were tentatively identified; gallic acid was predominant in thyme honey (127 mg/100 g), and linden honey contained high levels of rutin (70 mg/100 g) and galangin-glucoside. Antioxidant capacity varied notably by floral origin, with thyme and linden outperforming acacia samples. Significant correlations were found between total phenolics and ABTS (r = 0.86), and between ABS₄₅₀ and FRAP (r = 0.86). DPPH kinetics followed zero-order behavior (<i>R</i>² > 0.98). Principal component analysis (PC1 + PC2 = 88%) enabled preliminary separation by botanical origin. While based on a limited sample set, findings support the relevance of combining chromatographic, kinetic, and multivariate tools for exploratory honey characterization.