Descrição
Propolis is a substance produced by bees (Apis mellifera L.) after harvest of buds and bark of plants and by subsequent mixing with the salivary enzyme β-glucosidase. Bees use propolis in their combs as protection, to repair damage, to build aseptic locals for the eggs of the queen, and also as a thermal insulator. The composition of propolis varies geographically, with the available flora, the time of collection and the race of the bees. Different group of compounds can be found in propolis extracts, such as polyphenols, terpenoids, steroids and amino acids. These compounds have been associated with diverse biological activities: antibacterial, antifungal, antiviral, antioxidant, antimutagenic, antigenotoxic and genotoxic. Portuguese propolis has attracted the interest of researchers because of the opportunity for its economic valorization and the need to scientifically support the biological activities commonly assigned to samples of different origins. Thus, our objective relates to the analysis and study of Portuguese propolis, particularly in what concerns chemical characterization and evaluation of biological activities. A sample collected in Beira Alta was used to prepare an ethanol extract and this extract was tested in different assays, using Saccharomyces cerevisiae as biological model. Our results suggest that Portuguese propolis has antioxidant capacity when assessed by the DPPH assay. Accordingly, viability has improved when propolis was assayed, either by pre-incubation or co-incubation with yeast cells shocked with an oxidant agent (H2O2).
; Ferreira, A. M. 
