Propolis: Yet another amazing gift by the bees to the humans


Last Updated August 13th, 2019

Propolis: What is it?

When you think of bees, you think of honey. It is a wonderful thing and the only natural source of honey is the bee. However, honey is not the only thing that bees make. Bees utilize substances collected from plants, buds, and other exudates to create a natural resinous mixture called propolis. It is generally derived from poplars (trees of the willow family, found in the Northern Hemisphere) and conifers.

The word ‘propolis’ is derived from two words—pro meaning ‘at the entrance to’ and polis meaning ‘community’ or ‘city’. This implies that the product is used for hive defense. Propolis is used to seal cracks in and smooth out the inner walls of the beehive to keep out predators such as lizards, snakes, etc. and also to reduce the effects of wind and rain.  It also reduces microbial growth on hive walls and keeps the bees in the hive healthy.

Propolis: Facts

  • A bee’s colony is able to collect from 150 to 200 g of propolis in 1 year, though in some cases the collection could be less than that.
  • The color of propolis ranges from green to brown to reddish depending on its botanical source.
  • In some areas where poplars are not native plants, such as in Australia and South America, bees seek out other plants to produce propolis. This has a composition similar to that of the poplar propolis.
  • The beneficial effects of the constituents of propolis are more numerous in tropical regions than in temperate climates, reproducing the richer vegetal diversity observed in the former.

History of Propolis

Propolis was widely used in antiquity. The ancient Egyptians used propolis and wax to embalm and preserve the corpses because they were well aware of its anti-putrefactive properties. Greek and Roman physicians used it as mouth disinfectant. It had also been used as an antiseptic and healing product in wound treatment, prescribed for topical therapy of cutaneous and mucosal wounds.

During the Middle Ages, the study of propolis was not a very important topic, and it disappeared from mainstream medicine. However, it continued to exist in folk medicine and in the herbal medicine administered in the territories of Eastern Europe. Hence, it got the name “Russian Penicillin”.

It was later reintroduced into the pharmacopeias of England during the 17th Century. Between the 17th and 20th centuries, propolis became very popular in Europe because of its antimicrobial properties. The first scientific work describing its chemical composition and properties was published in 1908.

Current Use of Propolis

Nowadays, propolis is a natural remedy available in different forms for topical use and it can be found in a number of health food stores in the United States. It is also used in cosmetics and for treatment of various diseases in alternative medicine. Applications of propolis include formulations for cold (upper respiratory tract infections, common cold, and flu-like infections), as well as dermatological preparations useful in the healing of wounds and the treatment of burns, acne, herpes simplex, and genitals, and neurodermatitis. It is also used in mouthwashes and toothpaste and helps in treating gingivitis, caries, and oral ulcers.

Composition of Propolis

In general, propolis is composed of 50% resin and vegetable balsam, 30% wax, 10% essential and aromatic oils, 5% pollen, and 5% various other substances, including organic debris. Studies determining the composition of propolis began at the beginning of the 20th century. It was thought that the chemistry of propolis is like that of beeswax, quite complex but still constant.

In the 1960s, however, it was discovered by the analysis of numerous samples of bee glue from different geographic regions, along with the application of advanced laboratory methods, that it’s chemical composition is highly variable. Marcucci and Bankova et al. have registered over 300 known substances in propolis.

The composition of propolis varies from region to region (with vegetation), from season to season, and even from hive to hive. The major constituents of propolis from most of the sources are flavonoids (plant metabolites). Some of the principal esters (an ester is derived from an acid by replacing a hydroxyl group with an alkoxy group) of caffeic acid and flavonoids have been found to be responsible for the antibacterial, antioxidant, and anti-inflammatory characteristics of propolis.

Antimicrobial Properties of Propolis

The antibacterial properties of propolis have been well documented by various studies conducted across Eastern Europe. It has been shown before that propolis is more active on Gram-positive than on Gram-negative bacteria.

Alcoholic extracts of propolis are active against a wide range of dermatophytes at concentrations of 0.25 to 2%. The protozoa Toxoplasma gondii and Trichomonas vaginalis were killed within 24 h when incubated with 150 µg/ml of propolis.

Caffeic acid phenethyl ester (CAFE), which can be extracted from propolis, has been found to be toxic to a range of tumor-derived cell lines. A component active against the bacteria Bacillus subtilis, identified as 3,5,7-trihydroxyflavone, is also present in propolis. It is also very effective against staphylococci, where there are many components active against the microbe in propolis.

How does it work?

Different cells in the body express different portions of their DNA, leading to differences in cell and organ function. This is why despite having the same DNA, a liver’s functions are different from a heart’s. This happens through a process called transcription where the RNA polymerase binds with the DNA. DNA-dependant RNA polymerases in the bacteria are inhibited by several water-soluble, UV-absorbing components in propolis, thereby probably reducing their capability to bind with the DNA. This eventually affects their microbial action. It also has a synergetic effect with several antibiotics. These two factors help propolis’ antibacterial effects.

Anesthetic Properties of Propolis

Experiments on animals have proven that propolis can be used as a surface anesthetic with slight penetrating power and that it can be used in dental practice. Todorov et al. proved that the infiltrate action of propolis is equal to that of procaine, a common local anesthetic.

Healing Effects of Propolis

Propolis is excellent for burn management and enhancing skin cell proliferation, activation, and growth capacity. Gene expression is the process by which instructions in our DNA are converted into a functional product like protein, collagen being an example. The therapeutic efficacy of Propolis has been established by the higher extractability of collagen types I and III in the burn or injury site.

The restoration of the epithelium over a denuded area by natural growth or plastic surgery is called re-epithelialization. By creating a biochemical environment that supports re-epithelialization, propolis becomes beneficial as a wound healer and to regenerate tissues. For tissue regeneration, it is also able to scavenge for free radicals in the skin, which allows cells to regenerate.

Efficacy of Propolis

Research on the efficacy of propolis in the world is still in its early stages and scientists are yet to obtain results that are conclusive. All of the points regarding the efficacy of propolis are based on early research.

  • It has been shown that by taking propolis by mouth daily for 6-13 months, you can reduce canker sore outbreaks  
  • By applying 3% propolis ointment 5 times daily might help improve healing time for cold sores (blisters filled with fluid caused by viral infection around the lips) and reduce the pain caused by them.
  • The application of a 3% propolis ointment 4 times daily for 10 days might improve the healing of lesions in people with genital herpes. It might also heal lesions faster and completely than the conventional treatment of 5% acyclovir ointment in more cases.
  • Taking 60 drops of a preparation containing Brazilian green propolis daily for 7 days does not reduce the infection caused by H. pylori.
  • Taking a 30% propolis extract for 5 days can cure giardiasis (a type of intestinal infection) in more people than the drug tinidazole.
  • By applying propolis to the skin every 3 days might help treat minor burns and prevent infections.
  • Using a propolis mouth rinse 5 times daily for 1 week might help with the healing process and reduce the pain and swelling after mouth surgery.
  • Rinsing the mouth with a 30% propolis mouth rinse 3 times daily for 7 days helps reduce inflammation. It also improves the healing of sores in some people with mouth sores caused by chemotherapy.
  • The use of Brazilian green propolis extract 4 times daily for 7 days can prevent oral thrush in those with dentures.
  • Some early evidence exists that propolis might help prevent or reduce the duration of common colds and other upper respiratory tract infections.
  • Application of a 5% propolis solution vaginally for 7 days can reduce the symptoms of vaginal swelling and improve the quality of life in people with the condition.
  • Taking propolis by mouth daily for up to 3 months treats plane and common warts (kinds of warts). However, propolis does not seem to treat plantar warts (another kind of warts).

Side effects of Propolis

There is not enough literature to suggest that using propolis when someone is pregnant or breastfeeding is okay. If you are pregnant or breastfeeding, therefore, it is safer to avoid propolis. The known side effects of propolis are:

Asthma

The use of propolis is known to worsen asthma in certain cases. Avoid propolis if you have asthma.

Allergies

Few people are allergic to products containing honey, conifers, Peru balsam, poplars, salicylates, etc. If you are one of them, avoid the use of propolis. It may lead to an allergy.

Internal Bleeding

The use of propolis may slow down the process of blood clotting. So, propolis may increase the risk of bleeding in people with bleeding disorders. It may also cause a risk of internal bleeding during surgery. If you are to undergo surgery, please stop taking propolis at least two weeks before the surgery.

Appropriate Dosing

The appropriate dose of propolis depends on the user’s health, age, and other medical conditions. Propolis is a non-toxic natural compound, and the safe concentration for humans would be approximately 1.4 mg/kg-day or 70 mg/day. However, please understand that natural medicines can be unsafe and dosages are important. Always read the product labels and warnings to get a better idea of dosage and strictly follow them after consulting a physician or pharmacist to know if the medicine is required at all.

What does the future hold for propolis?

Propolis is a natural product that has been in therapeutic use since centuries. Beekeeping is a very old hobby of mankind and this has led to the revelation of several bee and honey-based products that work miracles on the human body. The first proper recorded use of propolis dates back to circa 300 BC, and it continues to be useful today in the form of home remedies, toothpastes, ointments, creams, drops, and dietary supplements It contains a wide spectrum of chemical compounds each with its own biological benefit, However, as revealed by numerous studies the world over in recent times, the constitution of propolis varies widely. The beneficial aspects of propolis are only just beginning to be understood since research is still in its early stages. In the meantime, it still remains one of the most useful natural products known to man throughout history, the medical value of which must not be overlooked.


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