Propolis

This article is about a product made by bees. For the fungus genus, see Propolis (fungus).

Propolis or bee glue is a resinous mixture that honey bees produce by mixing saliva and beeswax with exudate gathered from tree buds, sap flows, or other botanical sources. It is used as a sealant for unwanted open spaces in the beehive. Propolis is used for small gaps (approximately 6 millimeters (1⁄4 in) or less), while gaps larger than the bee space (approximately 9 millimeters (3⁄8 in)) are usually filled with burr comb. Its color varies depending on its botanical source, with dark brown as the most common. Propolis is sticky at and above 20 °C (68 °F), while at lower temperatures it becomes hard and brittle.

Two bars from a top bar hive that the bees have glued together using propolis. Separating the bars will take some effort as the propolis has hardened.

Propolis on the upper bar

When foraging, worker bees primarily harvest pollen and nectar, while also collecting water and plant resin necessary for the production of propolis.^[1] The chemical composition and nature of propolis depend on environmental conditions and harvested resources.^[2]

Types

Mixed types of propolis found in European countries with a moderate climate include two or more sources of plant resins (plant species) identified by composition, such as aspen, Mediterranean, poplar, Pacific, Brazilian green, Brazilian red, and Mangifera types of propolis.^{[3][citation needed]}

Purpose

 

Propolis drops in red (units in micrometers)

Bees seal the beehive with propolis to protect the colony from the elements, such as rain and cold winter drafts.

Propolis functions may include:^[4]

1. Reinforce the structural stability and reduce vibration
2. Provide improved thermal insulation to the hive and reduce water loss
3. Provides protection from pathogens, via anti-fungal and antibacterial properties^[5][6]
4. Make the hive more defensible against parasites and predators by narrowing the existing entrance (in wild colonies) to a single "choke point"
5. Mitigate putrefaction within the hive. Bees usually carry waste out of and away from the hive. However, if a small lizard or mouse, for example, finds its way into the hive and dies there, bees may be unable to carry it out through the hive entrance. In that case, they would attempt instead to seal the carcass in propolis, essentially mummifying it and making it odorless and harmless.

Composition

 

Propolis in hive

The composition of propolis varies from hive to hive, from district to district, and from season to season.^[7] Normally, it is dark brown in color, but it can be found in green, red, black, and white hues, depending on the sources of resin found in the particular hive area. Honey bees are opportunists, gathering what they need from available sources, and detailed analyses show that the chemical composition of propolis varies considerably from region to region, along with the vegetation. In northern temperate climates, for example, bees collect resins from trees, such as poplars and conifers (the biological role of resin in trees is to seal wounds and defend against bacteria, fungi, and insects). "Typical" northern temperate propolis has approximately 50 constituents, primarily resins and vegetable balsams (50%), waxes (30%), essential oils (10%), and pollen (5%).^{[citation needed]} An analysis of propolis from Henan, China found sinapinic acid, isoferulic acid, caffeic acid, and chrysin.^[8]

In neotropical regions, in addition to a large variety of trees, bees may also gather resin from flowers in the genera Clusia and Dalechampia, which are the only known plant genera that produce floral resins to attract pollinators.^[9] Clusia resin contains polyprenylated benzophenones.^[10][11][12] In some areas of Chile and Argentina Andean valleys, propolis contains viscidone, a terpene from Baccharis shrubs,^[13] and prenylated acids, such as 4-hydroxy-3,5-diprenyl cinnamic acid.^[14]

Overall, flavonoids, phenolic acids, and phenolic aldehydes are common constituents, while coumarins, stilbenes, and lignans are less common.^[15]

Traditional medicine

Propolis has been used in traditional medicine, with insufficient evidence to rate its effectiveness in the treatment of any illnesses.^[16]

Other uses

Musical instruments

Propolis is used by some string instrument makers (violin, viola, cello, and bass) as a varnish ingredient.^[17] A tincture of propolis may be used to seal the surface of newly made violin family bridges, and may be used in the maintenance of the bores of pan flute tubes.^{[citation needed]}

Claims that Antonio Stradivari used propolis in the varnish of his instruments were disproven in 2009.^[18][19]

References

1. Simone-Finstrom, Michael; Spivak, Marla (May–June 2010). "Propolis and bee health: The natural history and significance of resin use by honey bees". Apidologie. 41 (3): 295–311. doi:10.1051/apido/2010016.
2. Ferreira, Joselena M; Fernandes-Silva, Caroline C; Salatino, Antonio; Negri, Giuseppina; Message, Dejair (8 February 2017). "New propolis type from north-east Brazil: chemical composition, antioxidant activity and botanical origin". Journal of the Science of Food and Agriculture. 97 (11): 3552–3558. doi:10.1002/jsfa.8210. ISSN 0022-5142. PMID 28078783.
3. Popova, Milena; Trusheva, Boryana; Bankova, Vassya (2022). "Chemistry and Applications of Propolis". Reference Series in Phytochemistry. Springer International Publishing. pp. 657–688. doi:10.1007/978-3-030-91378-6_38. ISSN 2511-834X.
4. Simone-Finstrom, Michael; Spivak, Marla (May–June 2010). "Propolis and bee health: The natural history and significance of resin use by honey bees". Apidologie. 41 (3): 295–311. doi:10.1051/apido/2010016.
5. National Geographic p. 83 03/2020
6. Walker, Matt (23 July 2009). "Honeybees sterilise their hives". BBC News. Retrieved 24 July 2009.
7. Toreti VC; Sato HH; Pastore GM; Park YK (2013). "Recent progress of propolis for its biological and chemical compositions and its botanical origin". Evidence-Based Complementary and Alternative Medicine. 2013: 697390. doi:10.1155/2013/697390. PMC 3657397. PMID 23737843.
8. Qiao Z; Chen R (August 1991). "[Isolation and identification of antibiotic constituents of propolis from Henan]". Zhongguo Zhong Yao Za Zhi (in Chinese). 16 (8): 481–2, 512. PMID 1804186.
9. Mesquita, R. C. G.; Franciscon C. H. (June 1995). "Flower visitors of Clusia nemorosa G. F. W. Meyer (Clusiaceae) in an Amazonian white-sand Campina". Biotropica. 27 (2): 254–8. doi:10.2307/2389002. JSTOR 2389002.
10. Tomás-Barberán, F. A.; García-Viguera C.; Vit-Oliviera P.; Ferreres F.; et al. (3 August 1993). "Phytochemical evidence for the botanical origin of tropical propolis from Venezuela". Phytochemistry. 34 (1): 191–6. doi:10.1016/S0031-9422(00)90804-5.
11. Scott Armbruster, W. (September 1984). "The Role of Resin in Angiosperm Pollination: Ecological and Chemical Considerations". American Journal of Botany. 71 (8): 1149–60. doi:10.2307/2443391. JSTOR 2443391.
12. Bankova, V. (February 2005). "Recent trends and important developments in propolis research". Evidence-Based Complementary and Alternative Medicine. 2 (1): 29–32. doi:10.1093/ecam/neh059. PMC 1062152. PMID 15841275.
13. Montenegro G; Mujica AM; Peña RC; Gómez M; et al. (2004). . Phyton. 73: 145–154. ISSN 1851-5657. Archived from the original on 17 December 2014. Retrieved 7 November 2008.
14. Park, Y. K.; Alencar, S. M.; Aguiar, C. L. (2002). "Botanical Origin and Chemical Composition of Brazilian Propolis". Journal of Agricultural and Food Chemistry. 50 (9): 2502–2506. doi:10.1021/jf011432b. PMID 11958612.
15. Berenbaum, May R.; Calla, Bernarda (7 January 2021). "Honey as a Functional Food for Apis mellifera". Annual Review of Entomology. Annual Reviews. 66 (1): 185–208. doi:10.1146/annurev-ento-040320-074933. ISSN 0066-4170.
16. "Propolis". MedlinePlus, U.S. National Library of Medicine. 11 May 2020. Retrieved 5 December 2020.
17. Fulton, William (July 1997). "PROPOLIS SOAP – Used as a Ground for Violin Varnish". Southern California Association of Violin Makers. Retrieved 6 December 2020.
18. [https://www.classical-music.com/news/stradivarius-varnish-myth-debunked/ Stradivarius varnish myth debunked
19. Secret behind the composition of the varnish on Stradivari violins revealed

External links

 

Wikimedia Commons has media related to Propolis.

 

Look up propolis in Wiktionary, the free dictionary.

• "Propolis" . New International Encyclopedia. 1905.