Propolis is a mixture of resins, waxes and pollen from flowers and buds of plants supplemented with enzymes, and subjected to lactic acid fermentation in the digestive system of the bees. Propolis contains vitamins, essential oils, mineral salts, trace elements, hormones, and enzymes. Bees mostly prepare the propolis from protective substances separated by some plants bark and buds (e.g., poplar). These are different types of rubbers, waxes and resins. They cultivate it through their jaws knead and mix it with saliva, transport it to the hive and there they polish every surface, thereby protecting it from microorganisms. Moreover, they treated with propolis and inner surfaces of honeycombs. With propolis bees rub their body, thereby using its protective action.
Physical properties of the propolis
Propolis is a resinous material with shining dark yellow to khaki color. Freshly removed from the hive propolis is a soft, sticky mass. Flavour, physical and chemical properties are dependent on the type of the plants in the radius of the bee’s flight. Propolis has a pleasant aroma of herbal buds, honey and wax, bitterish and pungent flavor and darkens on long-term storage. In combustion emits a pleasant smell of resin. Upon warming quickly softens and becomes comfortable handling. At room temperature, solidifies, and in lower becomes brittle. Has a specific gravity between 1,112 and 1,136, no definite melting point, but usually melts between 80-105 ° C. Dissolves slightly in water , most preferably dissolves in alcohol, ether, chloroform, acetone.
Chemical composition of the propolis
Propolis has a complex chemical composition, which is still controversial. Contains approximately 55% resins, which include – flavonoids, phenolic acids, and ethers. Waxes and fatty acids 25-35% of plant and bee origin. Eterichni oil – 10%. Pollen – 5%, including proteins, probably from the pollen and free amino acids – 16 of which more than 1% of their total content. A proline plus arginine up to 45.8%. Tannins, 14 micronutrients – mostly iron and zinc, vitamins – only B3, mechanical impurities and others – generally 5%. It is important to know that the propolis from different geographic regions may have a different chemical composition and accordingly to show some differences in the biological activity.