Staphylococcus aureus (S. aureus) is one of the most frequent causes of hospital acquired infections. With the increase in multiple drug resistant strains, natural products such as propolis are a stratagem for new product discovery. The aims of this study were: to determine the in vitro antimicrobial activity of an ethanol extract of propolis; to define the MIC50 and MIC90 (Minimal Inhibitory Concentration - MIC) against 210 strains of S. aureus; to characterize a crude sample of propolis and the respective ethanol extract as to the presence of predetermined chemical markers. The agar dilution method was used to define the MIC and the high performance liquid chromatography (HPLC) method was used to characterize the samples of propolis. MIC results ranged from 710 to 2,850 µg/mL. The MIC50 and MIC90 for the 210 strains as well as the individual analysis of American Type Culture Collection (ATCC) strains of Methicillin-susceptible Staphylococcus aureus (MSSA) and Methicillin-resistant Staphylococcus aureus (MRSA) were both 1,420 µg/mL. Based on the chromatographic analysis of the crude sample and ethanol extracted propolis, it was concluded that propolis was a mixture of the BRP (SP/MG) and BRP (PR) types. The results obtained confirm an antimicrobial activity in relation to the strains of the S. aureus tested.

A geléia real (GR) é utilizada como produto revitalizante com sabor ácido e adstringente. Para evitar rejeição a este sabor, existem misturas de mel com GR. Existe legislação específica para o mel e para a GR separadamente, mas não para a mistura. Os objetivos do trabalho são: verificar se os métodos usados para o controle de qualidade do mel puro podem ser utilizados no controle do mel com GR e verificar a presença de GR pela determinação do 10-HDA. As análises incluíram: umidade, açúcares redutores, sacarose aparente, cinzas, hydroxymethylfurfural, sólidos insolúveis, atividade diastásica, acidez e 10-HDA. As amostras foram preparadas com 0-100% de GR no mel. Os resultados obtidos sugerem que dos métodos citados na legislação do mel somente o de cinzas foi adequado para todas as amostras. A análise de acidez (titulação direta) foi adequada de 0-30%GR; açúcares redutores 0-20%GR; umidade (método refratométrico) 0-10%GR e sugere-se o método de secagem por IV para as demais amostras. Os métodos para as análises da atividade diastásica, HMF, sacarose aparente e sólidos insolúveis foram inadequados para as amostras com GR. A presença de GR nas amostras foi comprovada pela análise do 10-HDA.

Royal jelly (RJ) is used as a revitalizing tonic. In order to avoid rejection to its acid taste, it is added to honey. There are regulations for honey and for royal jelly separately but not for the mixture. The objective of this work is, therefore, to verify if the same methods used for pure honey quality control can be used for honey mixed with royal jelly and also the presence of RJ through 10-HDA determination. The methods used were: moisture, reducing sugars, apparent sucrose, ash, hydroxymethylfurfural, insoluble solids, diastase activity, acidity and 10-HDA. Samples were prepared by adding 0-100% of RJ in honey. The results showed that the ash method was the only suitable one to all the samples. The acidity analysis (direct titration) was suitable to 0-30%RJ samples; the reducing sugar analysis was suitable to 0-20% RJ samples. Concerning moisture analysis the refractometric method is suitable to 0-10% RJ and the Infra Red method is suggested to be used for samples with more than 10% RJ. The methods for diastase activity, HMF, apparent sucrose and insoluble solids were inadequate for all samples with RJ. The presence of RJ in the samples was confirmed by the 10-HDA analyses.