Microbial communities associated with honey bees in Brazil and in the United States.

Honey bee colony losses worldwide call for a more in-depth understanding of the pathogenic and mutualistic components of the honey bee microbiota and their relation with the environment. In this descriptive study, we characterized the yeast and bacterial communities that arise from six substrates associated with honey bees: corbicular pollen, beebread, hive debris, intestinal contents, body surface of nurses and forager bees, comparing two different landscapes, Minas Gerais, Brazil and Maryland, United States. The sampling of five hives in Brazil and four in the USA yielded 217 yeast and 284 bacterial isolates. Whereas the yeast community, accounted for 47 species from 29 genera, was dominated in Brazil by Aureobasidium sp. and Candida orthopsilosis, the major yeast recovered from the USA was Debaryomyces hansenii. The bacterial community was more diverse, encompassing 65 species distributed across 31 genera. Overall, most isolates belonged to Firmicutes, genus Bacillus. Among LAB, species from Lactobacillus were the most prevalent. Cluster analysis evidenced high structuration of the microbial communities, with two distinguished microbial groups between Brazil and the United States. In general, the higher difference among sites and substrates were dependents on the turnover effect (~ 93% of the beta diversity), with a more pronounced effect of nestedness (~ 28%) observed from Brazil microbiota change. The relative abundance of yeasts and bacteria also showed the dissimilarity of the microbial communities between both environments. These results provide a comprehensive view of microorganisms associated with A. mellifera, highlighting the importance of the environment in the establishment of the microbiota associated with honey bees.

Antibacterial activity of Aroeira honeys produced in Minas-Gerais against bacteria of clinical importance / Atividade antibacteriana de méis de Aroeira produzidos em Minas-Gerais frente a bactérias de importância clínica

The biological activity of honey has been the subject of great scientific investigation. Bee products are widely used in folk medicine to treat human diseases due to their antibacterial and inhibitory potential action on different human pathogens. Ten honey samples produced by Apis mellifera in the northern of Minas Gerais state were tested against pathogenic microorganisms Staphylococcus aureus TSST (clinical isolated) and enterohaemorrhagic Escherichia coli ATCC 43895 for determination of their minimum inhibitory concentrations. The microdilution technique in broth Mueller-Hinton broth (MHB) was used in four concentrations (25, 12.5, 6.25 and 3.125%). There was a reduction of bacterial growth for the two target species at all concentrations tested. The optimal concentration for inhibition of S. aureus and E. coli were 3.125% (w/v). Therefore, the antibacterial activity of the tested samples evidences the potential of Aroeira honey produced in the north of Minas Gerais for therapeutic use, thus contributing to the aggregation value and commercialization of this type of honey.

A atividade biológica do mel tem sido objeto de relevante investigação científica. Produtos apícolas são amplamente utilizados na medicina popular para tratar doenças humanas por causa de sua potencial ação antibacteriana e inibitória a diferentes patógenos humanos. Dez amostras de mel produzidas por Apis mellifera, no norte do Estado de Minas Gerais, foram testadas contra os micro-organismos patogênicos Staphylococcus aureus TSST (isolado clínico) e Escherichia coli enterohemorrágica ATCC 43895 para determinação de suas concentrações inibitórias mínimas. A técnica de microdiluição em caldo Mueller-Hinton (CMH) foi utilizada em quatro concentrações (25, 12,5, 6,25 e 3,125%). Houve uma redução do crescimento bacteriano para as duas espécies alvo em todas as concentrações testadas. A concentração ótima para a inibição de S. aureus e E. coli foi de 3,125% (p/v). Portanto, a atividade antibacteriana das amostras testadas evidencia o potencial do mel de Aroeira produzido no norte de Minas Gerais para uso terapêutico, contribuindo para a agregação de valor e comercialização deste tipo de mel.

Brazilian green propolis compared to miconazole gel in the treatment of Candida-associated denture stomatitis.

Aim. To evaluate the efficacy of Brazilian green propolis in comparison to miconazole gel in the treatment of Candida-associated denture stomatitis. Methods. Forty-five denture stomatitis patients, with palatal mucosa erythema levels classified according to Newtons's criteria and with positive culture to Candida spp., were randomly divided into three treatment groups: 15 received miconazole gel 2%, 15 received propolis gel 2,5%, and 15 received propolis 24% for mouthwash. After four daily use lasting two weeks, they were reexamined for the denture stomatitis degree and for a second culture of Candida. The Wilcoxon's test was applied to compare the results of clinical classification of the denture stomatitis and the Candida spp. colonies numbers, before and after each treatment. The Kruskall-Wallis's test was used to compare efficacy among the three treatment groups. Results. There were a significant reduction or complete remission of denture stomatitis (P < 0.05) and a significant decrease of Candida colonies for the three groups (P < 0.05). There was no difference in the efficacy among the treatment groups (P > 0.05). Conclusion. Brazilian green propolis has a similar effect as miconazole in the treatment of Candida-associated denture stomatitis being an alternative in the therapeutics of this condition.

Brazilian green propolis on Helicobacter pylori infection. a pilot clinical study.

UNLABELLED: Recent in vitro studies suggest that propolis and some of its phenolic components are able to inhibit Helicobacter pylori growth. To date, there are no clinical studies. AIMS: To evaluate the effect of Brazilian green propolis on H. pylori-infected individuals. PATIENTS AND METHODS: Eighteen (11 females, 7 males, mean age 47 years) participants were included. Before treatment, all participants were submitted to gastroscopy, and H. pylori infection was confirmed by histology, urease test, and (13)C-urea breath test (UBT). Participants with UBT showing a delta over baseline (DOB) value higher than 4 per thousand were considered positive for H. pylori infection. Twenty drops from an alcoholic preparation of Brazilian green propolis were administered three times a day for 7 days. Clinical evaluation and UBT were performed at 1-3 days and at 40 days after the end of therapy to evaluate H. pylori suppression or eradication, respectively. RESULTS: All participants took all medication and completed the study. Eighty-three percent of the subjects did not succeed in suppressing or eradicating H. pylori. Two participants reached partial suppression after treatment, but became positive again at UBT performed 40 days after treatment. Another participant presented negative at UBT 40 days after treatment, not confirmed by a second UBT performed 100 days after treatment. CONCLUSIONS: Brazilian green propolis used in popular dose showed minimal effect on H. pylori infection. Larger studies with longer duration, larger dose, and different frequency of administration of propolis extract should be undertaken to define its role on H. pylori therapy.