The aim of this work was to investigate monthly, for one year the seasonality effect on the physicochemical properties (dry weight, flavonoids contents, pH and antioxidant activity) of ethanolic extract (EAP) of propolis produced by three different techniques (intelligent propolis collector, plastic screen or scraping) fifteen colonies of africanized bees. No differences (p>0.05) in the physicochemical properties due to the technique of propolis production and seasonality were observed.

O objetivo do presente trabalho foi avaliar o efeito da sazonalidade sobre algumas características físico-químicas (extrato seco, flavonóides totais, pH e atividade de oxidação) dos extratos alcoólicos (EAP) da própolis obtida mensalmente, durante um ano, por diferentes técnicas (coletor de própolis inteligente, tela plástica e raspagem) em quinze colméias de abelhas Apis mellifera africanizadas. Não foram observadas diferenças significativas (p>0,05) nas análises físico-químicas dos EAP, em função da sazonalidade e técnica de produção.

Propolis has been the subject of several recent studies, with the aim of elucidating its biological and pharmacological properties. Propolis has a well-known antimicrobial activity as well as antioxidant, antitumoral, antiinflammatory, and regenerative properties, but literature about its effects on the immune response is scarce. The goal of this work was to evaluate the propolis effect on macrophage activation by oxygen (H2O2) and nitrogen (NO) metabolite determination. Propolis was produced by africanized honeybees and hydroalcoholic solutions were prepared at different concentrations. Peritoneal macrophages were obtained from male BALB/c mice and culture cells were stimulated in vitro with propolis or interferon-gamma (IFN-gamma). In the in vivo assay, the animals were sacrificed after propolis treatment and cells were stimulated with IFN-gamma. We also investigated the co-stimulant action of propolis associated with IFN-gamma on macrophages. The results show that propolis induces a discreet elevation in H2O2 release and a mild inhibition of NO generation, depending on concentration. Propolis had no co-stimulant activity, diminishing IFN-gamma action on H2O2 and NO production. Data suggest that propolis acts on host non-specific immunity by macrophage activation.

Susceptibility to several ethanolic extracts of propolis (EEP) concentrations was tested with the population analysis technique in reference strains of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 35218). The results of these tests showed that all bacteria were killed by EEP concentrations approximately equal or higher (2.0% v/v- S. aureus; 10.0% v/v - E. coli) than the respective minimal inhibitory concentrations (MIC). Regarding the susceptibility to propolis, there was a homogeneity of data with the respective time kill curves showing a clear bactericidal effect during 6 to 9 h of exposition.

Ethanolic extracts of the bee glue, a resinous substance collected by honeybees called propolis, have been widely used in folk medicine since ancient times. Antibacterial, antifungal and thus antiseptic properties may represent the basis for the historical and present use of these extracts in dermatology, against inflammatory conditions and common colds. This work was carried out in order to verify possible biochemical alterations in some seric parameters of propolis-treated rats. It was shown that propolis possesses an antioxidant property and its administration did not affect either amylase and alanine transaminase activities or total protein concentration.

The in vitro activity of propolis against 118 Staphylococcus aureus, 108 Escherichia coli, 60 Salmonella typhimurium, 50 Candida albicans, 23 Candida parapsilosis, 19 Candida tropicalis and 14 Candida guilliermondii isolated from human infections was studied by the agar dilution method. Among the bacteria, the Gram-negative were the least susceptible organisms showing minimal inhibitory concentration (MIC) for 90% of the strains tested ranging from 22.5 mg/ml - 10,2% V/V to 23.1 mg/ml - 10.5% V/V. The MIC's for Candida ranged from 0.80 mg/ml to > 11 mg/ml (0.40% V/V to > 5.0% V/V), the strains of C. parapsilosis being the least susceptible. The relative order of susceptibility among all isolates, was: S.aureus > C. tropicalis > C. albicans > C. guilliermondii > C. parapsilosis > S. typhimurium > E. coli.