What is propolis?
Propolis is a natural substance made from plant resins, which is collected by honeybees (Apis mellifera) along with the nectar and pollen they need for food. It is also known as 'bee glue' and sometimes as 'hive dross'.
We have continued one man's research into this fascinating substance. Dr Zenon Sosnowski dedicated much of his life to discovering how the bee-produced substance could be used in cosmetic and pharmaceutical products. We use it in Herstat alongside the other ingredients to help soothe and moisturize the lips. It also acts as a preservative in our ointment, meaning we do not have to use parabens to preserve our products.
After emigrating to Winnipeg, Canada, Sosnowski worked as a lecturer at the University of Manitoba, which gave him the foundation to continue his research into how a purified propolis extract could be used in health foods, cosmetics and nutraceuticals. We have continued Sosnowski's work by using it in our Lip Care Ointment and Lip Care Stick with propolis.
Sticky at or above room temperature (20-25 degrees Celsius) while hard and brittle below these readings, this resinous mixture has been used by humans for hundreds of years for a range of purposes.
Depending on the type of plants where the bees have harvested the resin, in its crude form propolis can be brown, green, red, or black in color. Bees farmed in a specific region of Canada, where they mainly have access to poplar trees (Populus sp.), produce brown propolis.
In temperate climates, bees tend to use poplar trees as their source of resins, whereas in more tropical climates they mainly visit Clusia minor and Clusia rosea flowers, as well as plants from the Asteraceae (aka Compositae) family, which include Baccharis dracuncufolia and wild Rosemary. There are more than 25,000 other species of Asteraceae worldwide. To produce propolis extract, we gather propolis from hives in the Manitoba region of Canada, an area rich in poplar trees.
How is propolis made?
Honeybees, which are native to Europe, Western Asia, and Africa, must collect nectar which they convert to honey (they do this by breaking down the complex sugars within it using enzymes in their mouths) and eat it as a source of carbohydrates. They also consume pollen to gain important proteins. However, they also make special separate journeys where they only collect plant resins which they do not use for food.
Resins are secreted by plants when they have been damaged in order to close wounds on their surfaces and protect the plant from further damage or from insect attacks. They are also produced to protect new buds from free radicals. In effect, resins are a plant’s equivalent of our white blood cells or immune system.
The bees pick up the resins using their forelegs and mandibles (part of the insect's mouth), and then place them in the corbiculae (pollen sacs) on their hind legs. They can carry about 10mg of resin in each sac.
Once they get back to the hive, other bees have to pull the sticky substance off their legs, before mixing the plant resins with saliva and wax which is secreted by worker bees from eight wax-producing glands on their abdomens.
What do bees use it for?
Bees mix the various substances together by chewing on them. The result is crude propolis, which they use to seal cracks and holes in the beehive.
Another important role fulfilled by this substance was revealed in a book published in 1965 by Hoyt M. entitled The World of Bees. In his work, he stated that he had found, in an apiary at the University of Minnesota, USA, a dead mouse mummified in propolis.
Since then, the practice of embalming parasites and pests, such as beetles and other small predators which bees find too difficult to remove from the hive once they have been killed by stinging them, has been observed many times.
Propolis is also used by bees to patch up holes and cracks in the hive to keep heat from escaping and to protect the colony from invasion by other animals. It is also used to strengthen the wax honeycomb structure which contains their larvae and food stores.
Observations of bees over the years have determined that they only use pure propolis to fill gaps in their hive which measure from 0.1 to 3.5mm. Larger gaps are filled with a mixture of propolis and wax, or wax alone.
What do humans use it for?
Propolis possesses many beneficial properties and as a result, it is used in many commercially available cosmetic products, such as skin creams, face washes, shampoos, and toothpaste.
It is also used as a component of some varnishes, an ingredient of chewing gum, in car wax products, and in the manufacture of violins to enhance the appearance of the wood-grain.
It is likely that many other uses for propolis will be found as technologies, scientific knowledge, and research methods improve.
How is it processed for commercial use?
To produce the propolis extract used in Herstat, we use a complex extraction method devised by Dr Zenon Sosnowski over many years of research.
The amount of propolis created by a hive will depend on many factors, such as the bee breed, geographic and climate conditions, the type of hive provided by the bee farmers, the presence of resin sources in the area, and the strength of the colony.
Most propolis-collecting devices used by bee farmers, are designed to make use of the fact that bees tend to fill only small cracks with pure propolis. Propolis traps are wooden or plastic frameworks with rows of narrow gaps. They are designed to be placed in the hive and can be easily removed and replaced once the bees have sealed the gaps.
Raw propolis is scraped off the collection device and inspected for impurities, which can be removed by hand, such as small stones, other debris, wax, and honey. After this process has taken place, the propolis is cleaned and purified by machines so that smaller impurities, which might include traces of heavy metals or pesticides, are removed.
Finally, tests are undertaken to make sure that nothing else remains in the propolis which should not be there, and the substance can then be used in the manufacture of various cosmetics.
Propolis is such a stable material that, as long as it is kept in the dark in sealed containers, it can be stored for years without degrading or losing its useful properties.
Propolis has been used for hundreds of years for lots of different purposes, stretching back at least as far as 300 BC, when the ancient Egyptians and Greeks are believed to have used it. The Egyptians also used propolis in parts of their embalming process; for instance, they are believed to have used it as a glue for the mummification bandages.
Hippocrates (460 BC-377 BC), wrote about the properties of propolis during his time as a physician. He is thought to have used the substance for a variety of uses.
In more recent history, scientists have tried to improve on propolis, but they have not been successful. It seems the bees know best.
What are the chemical properties of propolis?
The chemical properties of propolis vary depending on which plants the bees collect resins from, the geographical positioning of these plants, and the season. The composition of the soil, the weather, as well as each plant's biological make-up, will have an effect on the components of the resin.
At a basic level, and before being purified, crude propolis contains plant resins, vegetable balsams, wax, essential oils, pollen, and bee saliva.
In a publication of the Journal of Membrane Science, a paper entitled Extraction of biologically active compounds from propolis and concentration of extract by nanofiltration states that more than 300 compounds have been found in raw propolis.
The main components of propolis are plant-derived substances called phenolics and flavonoids, which have several subgroups. These include flavones, flavonols and flavanones, (which are responsible for the red, orange and yellow colors in fruit and autumn leaves) and which are also partially responsible for the attractive coloring and smell of propolis.
There are around 20 million unique possible chemical combinations for propolis collected from different parts of the world.