Comparison of the Antioxidant Activity of Propolis Samples from Different Geographical Regions.

Propolis composition depends on several factors. The classification of propolis is based on its geographical location, color and agricultural characteristics. It is also classified according to the flora where the bees collect the resins, which represent the raw material for propolis production. Propolis possesses high antioxidant activity determined by its phenolic compounds. Due to diverse composition and possible impact on human health, eight samples of propolis were evaluated for their phenolic composition and antioxidant activity. Samples of Polish, Romanian, Turkish and Uruguayan origin propolis were used for phenolic spectrum determination using high performance liquid chromatography and photodiode array detection and in vitro DPPH and ABTS methods were used to determine the antioxidant activity of the extracts. PCA and HCA models were applied to evaluate the correlation between isolated polyphenols and antioxidant activity. The results confirmed variability in propolis composition depending on the geographical region of collection and the plant sources, and correlation between chemical composition and antioxidant activity. Results of PCA and HCA analyses confirm that Polish propolis is similar to that from different provinces of Romania, while Turkish and Uruguay are completely different. Polish and Romanian propolis belong to the poplar type. The assessed phenolic compounds of propolis samples used in the study are responsible for its antioxidant effect. The observed antioxidant activity of the analyzed samples may suggest directing subsequent research on prophylactic and therapeutic properties concerning cardiovascular, metabolic, neurodegenerative, and cancerous diseases, which are worth continuing.

Pollen Beads: A New Carrier for Propolis Active Compounds.

BACKGROUND: Pollen and propolis are two bee products with highly health promoting properties. But there are some limitations of raw propolis usage not only in daily consumption but also in putting it in food formulations. Propolis should be extracted to convert it into consumable form and ethanol is the first choice as a solvent. But ethanol consumption, either in health-wise or religious aspect, is one of the factors limiting the usage of propolis extract. The strong taste and strong smell of propolis are other factors. The immobilization of propolis active compounds could be a tool for overcoming either all or some of these factors. OBJECTIVE: This study was aimed at the immobilization of propolis active constituents on the surface of whole pollen grains. METHODS: Chemical composition of raw propolis was determined by using GC-MS technique. Total phenolic content and antioxidant activity of the samples were measured spectrophotometrically. The release property of the beads was determined. RESULTS: Immobilization efficiency was 53%. Total phenolic and flavonoid content of pollen, propolis and pollen-propolis beads were measured. It was determined that pollen-propolis beads contain more phenolics than pollen and propolis itself. Ferric reducing activity of the samples was also investigated and pollen-propolis beads showed better activity. Release behavior of pollen and pollen-propolis beads was studied in simulated digestive systems. Better release properties of pollen-propolis beads were achieved in all tested systems as well. These findings support the immobilization of propolis active compounds on the surface of whole pollen grains. CONCLUSION: It could be concluded that the product obtained, pollen-propolis beads, could be considered as a more valuable healthy product since the synergistic action of pollen and propolis.

Comparison between Phenolic Content, Antioxidant, and Antibacterial Activity of Algerian and Turkish Propolis.

BACKGROUND: Propolis is a natural resinous material produced by honeybees. The biological activity and phenolic profile of propolis were largely studied all over the world. However, only a few investigations have been carried out on Algerian and Turkish propolis. The aim of the present study was to compare the phenolic content, antioxidant, and antibacterial activity of propolis samples collected from different localities of Algeria and Turkey. METHODS: Propolis extracts were performed using maceration in ethanol 80%. Total phenolic and flavonoid contents were determined. Antioxidant and antibacterial activities were evaluated using FRAP assay and the MIC was determined against four bacterial strains (S. aureus ATCC 25923, E. coli ATCC 25922, P. aeruginosa ATCC 27853 and K. pneumonia). RESULTS: TP varied from 19.51 ± 0.86 to 219.66 ± 1.23 mg GAE/g. Whereas, TF varied from 5.27± 0.07 to 74.57 ± 1.03 QE/g. All samples showed good ferric reducing antioxidant power ranging from 267.30 ± 4.77 to 2387.30 ± 44.15 µmol Trolox eq./g. All Algerian propolis samples displayed a more pronounced activity against S. aureus ATCC 25923 with MIC values ranging from 0,04 ± 0.00 mg/mL to 0.30±0.06 mg/Ml, with an activity 30 times more powerful than Anatolian propolis. While, Anatolian propolis samples were most active against P. aeruginosa ATCC 27853 with MIC values ranging from 0.20±0.00 mg/mL to 0.60±0.00 mg/Ml, with an activity 5 to 10 times more powerful than Algerian propolis. CONCLUSION: Algerian and Anatolian propolis possessed considerable phenolic and flavonoids contents. In addition, they exhibited interesting antioxidant and antibacterial activities. Our findings suggest that both propolis could be useful in the food and pharmaceutical industries.