Identification by UPLC-DAD of Phenolic Compounds from Native Nectariferous Flowers and Their Associated Honeys from Yucatán, Mexico

Honey biosynthesis is a biochemical transformation process in which nectar-derived phenolic compounds undergo selective modification during collection, enzymatic processing and maturation within the hive. This study investigated the influence of geographical origin (GeO), botanical origin (BO) and drying treatment (DT) on the phenolic composition and antioxidant activity of nectariferous flowers and their corresponding honeys from Yucatán, Mexico. A 5 × 8 × 2 multifactorial design was applied to floral biomass, whereas 4² and 3 × 6 multifactorial designs were used for monofloral and multifloral honeys, respectively. Total phenolic content (TPC), antioxidant activity (DPPH) and individual phenolic compounds were determined by the Folin–Ciocalteu assay, DPPH radical scavenging assay and UPLC-DADFreeze-dried flowers showed higher total phenolic content, antioxidant capacity, and flavonoid concentrations than oven-dried flowers. Among the floral samples, Gymnopodium floribundum from Peto showed the highest total phenolic content (1,754.69 ± 128.67 mg GAE/100 g DM) and antioxidant capacity (96.82 ± 1.09% DPPH inhibition), whereas Bursera simaruba from the same locality had the highest catechin concentration (998.72 ± 1.45 mg/100 g DM). In contrast, honey displayed a more selective phenolic profile, characterized by lower flavonoid abundance and the predominance of protocatechuic acid (84.76 ± 0.09 mg/100 g DM). These findings indicate that honey does not proportionally preserve the floral phenolic profile but instead emerges from a selective biochemical reorganization in which individual metabolites are differentially retained, transformed, enriched, or depleted during nectar conversion, providing new insight into the metabolomic transition from nectar to honey.