Region-Specific Chemical and Palynological Characterization of Propolis from Karasuver (Kangal, Sivas, Türkiye)

This study presents an integrated chemical, palynological, and spectrophotometric characterization of a propolis sample collected from the Karasüver (Kangal, Sivas) region, located in the transitional zone between Central and Eastern Anatolia. The volatile and semi-volatile chemical composition was determined by Gas Chromatography–Mass Spectrometry (GC-MS), the botanical origin was evaluated by microscopic pollen analysis, and the total phenolic content (TPC) was quantified using the Folin–Ciocalteu method. GC-MS analysis revealed a distinctive chemical profile dominated by flavonoids, followed by aromatic compounds, whereas naturally occurring esters were present only at minor levels. The high concentrations of pinostrobin (14.48%), chrysin (14.40%), and pinocembrin (7.63%) clearly classify this sample as a characteristic Poplar (Populus) type propolis. Palynological analysis identified Asteraceae (20.24%) and Fabaceae (13.50%) as the dominant pollen families, reflecting the steppe vegetation of the region. Additionally, the presence of Pinaceae (9.58%) pollen is consistent with the detection of specific sesquiterpenes (e.g., β-eudesmol) in the GC-MS profile, indicating a secondary resin contribution from coniferous trees. Although Populus pollen was detected at low levels, the chemical abundance of poplar-specific markers confirms that Populus spp. are the primary resin source. The total phenolic content was determined as 216.12 ± 0.58 mg GAE/g, demonstrating a very high antioxidant potential. Compared to previous regional studies reporting lower values, these results highlight a strong association between the flavonoid-rich chemical profile and the elevated TPC value. Overall, Sivas–Kangal (Karasüver) propolis represents a high-quality bioactive product with a rich phenolic composition and significant antioxidant capacity.