Propolis (pre+city, i.e. defence of the city or the hive), is a sticky resin collected by bees and used for the sterilisation of hives.
Ancient civilizations used propolis for its healing properties. It includes more than 300 compounds. The majority of them are polyphenolic.
The surveys consider that it has antibacterial, antiviral, anti-cancer and anti-inflammatory properties.
Source: PubMed.gov (National Biotechnology Information Centre and National Library of Medicine of USA).