Physicochemical Properties and Bioactive Potential of Algerian and Imported Propolis

This study compares the phytochemical composition, physicochemical characteristics, and biological activities of ethanolic propolis extracts from Tipaza, Algeria, and a commercial source. Algerian propolis exhibited higher dry matter (97.37 ± 0.16%), ash content (4.34 ± 0.25%), titratable acidity (6.79 ± 0.40 mg/g), and extraction yield (32.14 ± 2.10%) than the commercial sample (19.65 ± 1.50%). Total polyphenols (203.32 ± 3.80 mg GAE/g) and flavonoids (53.03 ± 2.20 mg QE/g) were also higher, suggesting enhanced antioxidant potential. LC–MS/MS analysis identified 17 and 14 secondary metabolites in Algerian and commercial propolis, respectively, with a predominance of flavonoids (apigenin, myricetin, luteolin, quercetin-3-glucoside, rutin, catechin) and phenolic acids (caffeic acid, p-coumaric acid, salicylic acid) in the Algerian samples. In contrast, commercial propolis contained fewer flavonoids and phenolic acids, with notable compounds including 2-methoxybenzoic acid, resveratrol, and oleanolic acid, reflecting differences in botanical origin and chemical profiles. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses revealed greater thermolability and lower thermal stability in Algerian propolis, consistent with its higher content of thermolabile phenolic compounds. X-ray diffraction confirmed a more amorphous structure, while FTIR and ¹H NMR spectra indicated hydroxyl, carbonyl, and aromatic functional groups, reflecting a complex and less processed matrix. Algerian propolis showed stronger antioxidant activity (IC₅₀ = 0.20 mg/ml) and superior antimicrobial effects, particularly against Staphylococcus aureus . Overall, these findings highlight the influence of geographical origin, botanical composition, and processing on propolis quality, and underscore Algerian propolis as a promising natural source of bioactive metabolites for biomedical and nutraceutical applications.