Unveiling the Chemical Signature of Abruzzo Bee Pollen: Markers of Authenticity, Bioactive Phytochemicals and Antioxidant Activity

Bee pollen is a complex natural matrix rich in bioactive compounds, a valuable source with high nutritional value. Its chemical composition is highly variable and is influenced by botanical origin and geographical area, posing significant challenges for quality control and authentication. In this study, the volatile and semi-volatile fingerprints of Abruzzo bee pollen samples were investigated by HS–GC–MS and GC–MS, enabling the identification of 61 compounds. GC–MS profiling revealed distinct chemical patterns among the investigated bee-pollen samples, with multifloral samples (MP7–MP13) and chestnut pollen (CP1–CP2) showing a similar profile associated with the occurrence of linoleic acid. Moreover, the aldehydic volatile fingerprint further contributed potential chemical markers of botanical and territorial origin, particularly hexanal and nonanal, which may represent characteristic volatile markers of this botanical source, while 3-methylbutanal as well as sulphureous compounds contributed to the distinctive volatile profile of MP1 and MP2. These latter exhibited a distinctive phytochemical profile characterized by umbelliferon (UMB) and 7-isopentenyloxycoumarin (7-IPC), compounds with recognized bioactive properties that may contribute to the functional value of bee pollen. Antioxidant capacity was evaluated using ABTS and DPPH radical scavenging assays. The highest antioxidant activity was observed in MP1 and MP2, potentially reflecting the contribution of oxyprenylated coumarins. The presence of these coumarin derivatives may also provide insights into the botanical origin of the samples and their potential chemotaxonomic relevance. Principal component analysis (PCA) revealed clear chemical distinctions associated with botanical origin, effectively discriminating multifloral samples (MP1–MP13) from Castanea sativa L. (CP1–CP2) and Hedera helix (EP1–EP2).