How do bees make propolis to seal their hives?
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How Bees Make Propolis to Seal Their Hives
Collection of Plant Resins and Exudates
Bees produce propolis, also known as "bee glue," by collecting resinous substances from various parts of plants, including buds, leaves, and bark exudates. These resins are primarily sourced from trees such as poplars, pines, birches, and willows, among others1 2 5. The bees gather these materials painstakingly, often from specific plants that produce secondary metabolites with antimicrobial properties6.
Mixing with Saliva and Beeswax
Once the bees collect the plant resins, they mix them with their saliva and beeswax. This combination results in a sticky, resinous substance that is both adhesive and protective5 7. The bees' salivary enzymes partially digest the resins, enhancing the material's properties for use within the hive5.
Application in the Hive
Bees use propolis to seal cracks and crevices in their hives, smooth out internal walls, and protect the entrance against intruders and environmental threats like wind and rain2 5. The adhesive properties of propolis make it an effective material for these purposes, and it adheres well to various substrates, including glass and PTFE, even under wet conditions9.
Chemical Composition and Variability
Propolis is composed of a complex mixture of more than 300 compounds, including phenolic compounds, aromatic acids, essential oils, waxes, and amino acids1 7. The specific chemical composition of propolis can vary depending on the plant sources, geographical location, and season1 7. For instance, propolis collected from different regions may contain varying concentrations of n-alkanes, n-alkenes, and triterpenoids, reflecting the local flora3.
Protective and Antimicrobial Properties
One of the primary functions of propolis is to act as a natural antibiotic, preventing bacterial, viral, and fungal infections within the hive5. It also serves to embalm intruders like mice and reptiles that may enter the hive, preventing their decomposition and potential spread of pathogens6. The antimicrobial properties of propolis are well-documented and have been utilized in various medicinal applications, including wound healing and treatment of infections2.
Conclusion
Bees make propolis by collecting plant resins and exudates, mixing them with their saliva and beeswax, and using the resulting substance to seal and protect their hives. The chemical composition of propolis is highly variable, depending on the plant sources and environmental conditions. Its primary functions include sealing cracks, smoothing hive walls, and providing antimicrobial protection, making it an essential material for the health and maintenance of bee colonies.
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Most relevant research papers on this topic
Composition and functional properties of propolis (bee glue): A review
Propolis, a natural substance collected by honey bees from various plants, serves as an antiseptic, prevents bee-hive infections, and has been used in folk medicine for centuries.
Highly CitedPropolis: A Wonder Bees Product and Its Pharmacological Potentials
Propolis, a natural resinous mixture produced by honey bees, has potential antimicrobial applications for cold syndrome, wound healing, and treatment of various skin conditions.
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Urban honey bees collect petroleum derivatives from asphalt as an additional ingredient in their propolis, highlighting the need for caution when considering its chemical composition for biological and pharmacological applications.
Rigorous JournalAntioxidant properties of bee propolis and an important component, galangin, described by X-ray crystal structure, DFT-D and hydrodynamic voltammetry
Galangin, a flavonoid found in bee propolis, is an excellent superoxide radical scavenger, potentially even better than quercetin, with two modes of action: extraction of H atoms and - interaction.
Rigorous Journal