Phytochemical and antioxidant profiling of propolis extract sourced from three different geographical sites

AbstractPresent study was designed to explore the phytochemical and antioxidant variations in propolis. Crude propolis samples were collected from four different states (Himachal Pradesh, Punjab, Haryana and Rajasthan) of India and were processed for dewaxination by heating at 50 - 70°C and then extract was prepared in 70% ethanol. Each extract was filtered, dried and stored at 4°C for further use. Phytochemical quantification such as total polyphenolics content (TPC), total flavonoid content (TFC), total flavones and flavonols content (TFFC) and total alkaloid content (TAC) was carried out. Antioxidant profiling includes “2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, total antioxidant capacity (TAC), Ferric Reducing and Reducing Power (FRAP), 2,2’azino bis(3ethylbenzothiazoline6sulfonic acid) (ABTS)” and hydrogen peroxide scavenging activity with results expressed relative to standards. Results of the revealed remarkable variations in phytochemical content and antioxidant potency in all propolis extracts of Himachal Pradesh, Punjab, Haryana and Rajasthan. TPC was found significantly higher in Punjab (400 µg) and lower in Himachal Pradesh (193 µg), and similar trend was observed in mean TPC, with Punjab leading (236 mg/GA g). Total flavonoid content (TFC) peaked in Haryana (568.2 µg), while Rajasthan showed significantly higher total flavone and flavonols content (429.8 µg). However, significantly higher alkaloid percentage was observed in propolis extract of Haryana (56.5%). Antioxidant profiling revealed that stronger DPPH scavenging potency (30.02%), FRAP (0.431 mg TE/100 cm3), ABTS (94.83 µmol/L), TAC (92.43 mg/g ascorbic acid) and H2O2 scavenging activity (90.62%) was observed in propolis extract of Himachal Pradesh respectively indicating notable regional variations in the bioactivity of propolis extracts.