Propolis it is a natural resinous substance that honeybees (Apis melifera, L.) collect from buds and
exudates of plants and transformed in the presence of bee enzymes. This substance plays an important
role in the hive as a construction and defence material due to its chemical and biological properties.[1]
Propolis composition is extremely complex and dependent on its vegetal source, geographical location
and climatic conditions. Typically this natural product includes resin (50%), beeswax (30%), essential
oils (10%), pollen (5%) and other organic compounds (5%).[2] Due to the abundance in phenolic
compounds (flavonoids, phenolic acids and their esters) and to its biological and pharmacological
properties this group of substances became the target of many research studies in propolis.
This work outlines an extensive qualitative and quantitative characterization of the phenolic
composition of Azorean islands propolis. For that, eleven samples of propolis, from S. Miguel and
Terceira island, were extracted and characterized according to the previous work.[3] The HPLC results
show a similar chromatographic profile for all samples, despite their origin, with 37 compounds identified
by ESI-MS/MSn analysis and confirmed by HPLC-DAD. Although the samples revealed a similar
phenolic composition, significant differences in the concentrations of the different compounds were
found, probably due to the differences in flora distribution around the beehive, and therefore resin
availability for bees
