Propolis has always been the great protagonist of our winters, but how much do we really know about it? It is a wax-resinous substance that bees produce from resins gathered from the buds of various trees, and as such it concentrates within itself all the functional elements produced by the plant.

Its name derives from the Greek pro, meaning "in defence of," and polis, meaning "city" — it is in fact used by bees to coat the walls of the hive, polish the cells where eggs are laid, and seal cracks. Its hygienic and protective function is due to its particular content of resins, waxes, essential oils, derivatives of benzoic and cinnamic acid, and flavonoids such as chrysin, pinocembrin and galangin.

The composition of propolis changes continually, as does its colour — from yellowish-brown or reddish — depending on the seasons and the habitat in which the bees live, and it is always different precisely because it is the product of a living laboratory. The distinctive element, however, is a particular composition of polyphenols, among which galangin stands out, found in high quantities in high-quality propolis extracts.

Its properties pair well with the antioxidant activity of the substances found in grapefruit seeds: bioflavonoids characteristic of citrus fruits such as hesperidin, kaempferol and naringin, the latter being responsible for the bitter taste of the seeds. Once ingested, naringin is then converted in the intestine by the intestinal microflora into naringenin and subsequently absorbed.

Photo: © Bios Line

The properties of grapefruit seeds were discovered by chance in the early 1980s, simply by observing that when mixed with composting material they prevented its fermentation and decomposition. Subsequently, grapefruit seed extract was the subject of studies that scientifically demonstrated its activity (in 2004, in the research "Antimicrobial activity of grapefruit seed and pulp ethanolic extract").

Today we can benefit from products that contain the precious combination of propolis and grapefruit seeds and their beneficial effects against cold-related complaints.

By Bios Line