Natural bioactive compounds of honey and their antimicrobial activity

Honey is a complex and variable mixture that contains more than 180 biochemical compounds from various molecule families. This mixture is obtained after processing the nectar out of plant food sources at the level of the bee abdomen. The bioactive components found in this natural product are in charge of its antimicrobial properties. Honey is used for its antibacterial actions against Gram-positive (Gram+) and Gram-negative (Gram-) bacteria, its anti-fungal and antimycotic actions against moulds and yeasts, along with its protozoal and antiviral activities. This literature review outlines the natural antimicrobial potential of honey; it explains the factors responsible for this potential and spells out their mechanisms of action. Osmotic pressure, water activity, the acid content of honey, presence of bioactive compounds like hydrogen peroxide (H2O2), phenolic acids, flavonoids, methylglyoxal (MGO), defensin-1, lysozyme, volatile compounds as well as antibacterial products secreted from the lactic bacteria that are behind this antimicrobial activity. This potential basically depends on the biological activities of the initially harvested floral source, its geographical origin, season, storage conditions, honey age, health of bee colonies and suitable beekeeping practices.