Antioxidant Potential of Propolis, Bee Pollen, and Royal Jelly: Possible Medical Application

Table 1

The results of the research on the dependence between the solvent used for the extraction and the antioxidant properties of the obtained propolis and bee pollen extracts.

Source	Type of bee products	The used solvents	The dependence between the used extraction solvent and the properties of the obtained extract
Bittencourt et al. [31]	Green and brown Brazilian propolis	Ethanol (95%) extraction, evaporation, and dissolving in 80% ethanol and then partitioning with hexane or dichloromethane.	Antioxidant activity showed considerable differences depending on the used solvent and propolis type.; In DPPH assay, the strongest antioxidant activity was found in dichloromethane and ethanol extracts of green propolis as well as dichloromethane extract of brown propolis with the IC50 values at least two times less than in the other cases, namely, in hexane extract of brown propolis, ethanol extract of brown propolis, and hexane extract of green propolis.
Narimane et al. [34]	Algerian propolis collected from Beni Belaid, Jijel (northeast of Algeria)	CH2Cl2-MeOH (1 : 1, v/v) extraction followed by MeOH-H2O (70 : 30, v/v) one, concentrating and dissolving in boiling water. Then the water solution underwent successive extraction by using of chloroform, ethyl acetate, and n-butanol.	The DPPH, ABTS, FRAP, and CUPRAC methods were applied to determine antioxidant activity.; The ethyl acetate and n-butanol extracts proved to be the most effective ones.
Sun et al. [3]	Beijing propolis	Water, 25%, 50%, 75%, 95%, and 100% ethanol.	The 75% extract demonstrated the highest antioxidant capacity measured by DPPH, ABTS, FRAP, ORAC, and CAA methods.
LeBlanc et al. [11]	Six pollen types (mesquite, yucca, palm, terpentine bush, mimosa, and chenopod) collected in Arizona between March and November	Water, methanol, ethanol, propanol, 2-propanol, acetone, dimethylformamide, and acetonitrile.	Antioxidant activity showed considerable differences depending on the used solvent.; In FRAP assay, methanol and dimethylformamide extracts displayed the greatest activity values, whereas those obtained with the application of acetonitrile displayed the lowest ones. Acetone extracts were also found to possess low activity in the case of most types of bee pollen.; Similar results were obtained with using DPPH assay.
Silva et al. [41]	Pollen loads collected from Melipona rufiventris (stingless bees) colonies in Brazil	Fractional extraction with subsequent using of ethanol, n-hexane, and ethyl acetate.	The DPPH method was applied to determine antioxidant activity.; The ethyl acetate extract proved to be the most effective one.; The ethanol extract showed much less (more than six times) efficiency, whereas the capacity of the hexane extract was slight (practically inactive).
Chantarudee et al. [42]	Bee pollen collected in Thailand in the summer (June), its main component being identified as pollen of corn (Z. mays L.)	Subsequent application of 80% methanol, dichloromethane, and hexane.	The antioxidant activity of the obtained extracts was estimated by DPPH assay.; The hexane extract proved to be completely inactive, whereas that obtained with using dichloromethane showed the best antioxidant properties, comparable even with the reference antioxidant—ascorbic acid.
Maruyama et al. [43]	Bee pollen from Cistus sp. of Spanish origin. Bee pollen from Brassica sp. of Chinese origin	Water and 95% ethanol	In rats with induced hind paw edema, the oral administration of bee pollen water extract had practically no effect, while ethanol extract displayed the greatest effectiveness in the inhibition of paw edema.