Chemical Composition and Biological Evaluation of Algerian Propolis from Six Different Regions

Propolis is considered a natural resin produced by the bee and is still used in folk medicine. Six propolis samples from Apis mellifera (P1-P6) collected from different regions in Algeria were investigated for their contents and biological activities. The obtained results revealed that propolis P1 exhibited the highest total phenolics (210.93 mg GAE/g propolis), total flavonoids (34.33 mg QE/g propolis), and tannins (23.36 mg CE/g propolis). For antioxidant activities, P1 showed strong free radical scavenging activity with EC50 values of 0.055, 0.0306, 0.109 and 0.071 mg/mL, respectively for DPPH, ABTS, FRAP, and phosphomolybdenum assays. On the other hand, all propolis demonstrated antibacterial activities against G+ve bacteria (S. aureus) with slightly higher activities that were associated with P1 and P5 (9.83 and 10.92mm, respectively). P5 exhibited the lowest MIC and MBC against S. aureus with values of 62.5 and 125 µg/ml, respectively. Furthermore, all propolis had moderate to low antimicrobial activities against C. albicans (yeast) with moderate activities for P1 and P6 (13.33 and 8.50 mm, respectively). Chemical profiling of the most bioactive propolis samples (P1, P4, and P5) using HPLC‑fingerprint analysis mainly led to detecting phenolic acids and flavonoids in variable percentages.