Chemical Composition and Biological Activities of Propolis From Eastern Anatolia: Antioxidant, Enzyme Inhibitory, and...

Propolis is recognized for its biological activities; however, its chemical composition varies according to environmental conditions, which presents challenges for quality standardization and biological evaluation. Although propolis has been widely investigated, information regarding variation among samples collected from geographically close locations within the same region is limited. Therefore, this study investigated whether propolis samples obtained from different locations within Erzincan Province exhibit differences in chemical composition and biological activities and evaluated the relationship between environmental conditions and propolis characteristics. Eleven propolis samples collected from Erzincan, Türkiye, were analyzed for phenolic composition, antioxidant capacity, antimicrobial activity, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase inhibitory activities. Twenty-eight compounds were identified, with gallic acid, protocatechuic acid, chlorogenic acid, hydroxybenzaldehyde, caffeic acid, and vanillin detected as major constituents. AChE inhibitory activity varied between 1.28 and 6.44 µg/mL, while BChE inhibitory activity varied between 1.85 and 9.66 µg/mL. All samples exhibited antibacterial activity. Total phenolic and flavonoid contents were 141.70-255.04 mg GAE/g extract and 30.48-93.81 mg QE/g extract, respectively. The KMH sample showed the antioxidant activity. The results demonstrated variation in phytochemical composition and biological activities among propolis samples collected within the same province, indicating associations between flora, environmental conditions, propolis quality, and bioactivity.