Analysing chemical composition and antimicrobial activity of geopropolis from Melipona scutellaris: HPLC-DAD and in vitro/in silico investigations.

This study evaluated the chemical profile, antimicrobial activity, and the presence of potentially toxic elements in geopropolis extracts produced by Melipona scutellaris in the Recôncavo region of Bahia, Brazil. It was found that the major chemical compounds belong to the class of phenolic compounds, with emphasis on the presence of gallic acid. In this study, no potentially toxic elements were found in the analysed geopropolis. Regarding the antimicrobial potential, gram-positive bacteria were susceptible to the action of geopropolis extract at concentrations of 0.25 to 2.5 mg.mL-1, highlighting its microbiological activity against Streptococcus mitis (ATCC 00456) and Candida albicans (CCMB 251). Thus, this geopropolis extract can be used as a bacteriostatic rather than a bactericide. Our results suggest the potential for the economic and therapeutic use of M. scutellaris geopropolis, adding value to one of the meliponiculture products.

A new cyclodipeptide from Tetragonisca angustula honey active against Neospora caninum and in silico study.

A new cyclic natural compound formed by succinic acid and two alanine amino acid units was isolated from the Tetragonisca angustula honey extract. The chemical structure of 1 was established based on spectroscopic data analysis, including one- (1H and 13C NMR) and two-dimensional NMR techniques (1H-1H-COSY, HSQC and HMBC). A primary culture model previously infected with Neospora caninum was used to evaluate 1 for two time intervals (24 and 72 h), showing a reduction (40-56%) of the number of tachyzoites in the first 24 h and until 72 h, a dose-dependent reduction in parasite proliferation (25-50%). Glial cells treated with 1 did not demonstrate toxicity at concentrations up to 25 ug/mL. Treated and infected cultures showed an increase in NO when compared to control cells in 24 h and 72 h. In silico studies suggest that the new compound may affect DNA synthesis and impair -protein production.

Chemical Profile of Elements in the Stingless Bee Melipona scutellaris (Hymenoptera: Apidae: Meliponini) from Sites with Distinct Anthropogenic Activities.

Stingless bees are pollinators in forests and crops that, during foraging, may be exposed to several environmental xenobiotics, including metallic elements. This study evaluated the presence of magnesium (Mg), aluminum (Al), calcium (Ca), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), molybdenum (Mo), cadmium (Cd), barium (Ba), and lead (Pb) over the body surface of the stingless bee Melipona scutellaris visiting areas with different anthropogenic activity levels. The analyses were carried out using scanning electron microscopy with X-ray energy-dispersive spectroscopy (SEM/XEDS) and all tested elements were identified. Lead was the most abundant element in all samples, whereas Mn had the lowest abundance. High amounts of Cu and Zn were detected in the areas with metallurgic industries. The presence of metals on the body surface of this stingless bee varied according to the level of human activities in the studied areas.

Rheological and sensorial evaluation of yogurt incorporated with red propolis.

The aim of the present study was to evaluate the use of red propolis extract, as a natural additive, in yogurt. For this, yogurt was produced with red propolis extract (YRP), to replace the additive chemical potassium sorbate, used in the commercial yogurt (CY). Analysis for apparent viscosity, texture and sensorial acceptance were performed. Apparent viscosity and texture measurements of the samples were similar to the control. Sensory evaluation showed that the samples of YRP reached a mean score of 9 on the hedonic scale, the same score found for CY. Regarding the purchase intention, the samples of YRP showed a positive intention by 64.45% of the consumers, and for CY, 68.89%. For the taste, texture, aroma and consistency, the scores were in the range from 8 to 10, for both samples. It can be concluded that the yogurt incorporated with red propolis presents potential for its commercialization in the Brazilian market.

Genetic Variability of Melipona subnitida (Hymenoptera: Apidae) in Introduced and Native Populations.

Melipona subnitida (Hymenoptera: Apidae) is a stingless bee native to Caatinga biome in Brazil, well adapted to hot and dry climate of that region and has been traditionally explored for honey production. Here, we evaluate the genetic structure of 173 colonies of M. subnitida in northeast Brazil by partially sequenced mitochondrial genes cytochrome oxidase I (COI) to compare an introduced population isolated for 30 yr into the Island of Fernando de Noronha (IFN) with the continental populations. We identified high haplotype diversity (0.8220) with 14 haplotypes on the continental populations, being three new ones, compared with the database GenBank. The haplotype H4 was present at the center of network, occurring in four localities on mainland and fixed as a single haplotype on IFN. We propose that the island populations originally introduced carried one haplotype (H4), even though IFN population is suffering pressure by island effect through changes on morphology. Studies on island populations could be a model to understand the dynamics of isolated populations and sustainable management of this biome to preserve M. subnitida.

Microbiological Assessment, Nutritional Characterization and Phenolic Compounds of Bee Pollen from Mellipona mandacaia Smith, 1983.

This study aims to assess the microbiological parameters and the chemical composition of 21 samples of stingless bee pollen (Melipona mandacaia) from two regions of Bahia, Brazil (João Dourado and Uibaí), with particular emphasis on the nutritional value, total phenols and flavonoids and fatty acids composition. Regarding the microbiological quality, the studied microorganisms (moulds and yeasts, coliforms, Escherichia coli, Staphylococcus aureus, Salmonella sp., psychrotrophic and sulfite-reducing Clostridia) were absent in all samples. On the other hand, the values obtained for the aerobic mesophilic microorganism ranged from 11.0 ± 1.0 to 1.32 ± 1.2 cfu∙g-1 (JD samples) and from 282 ± 3.82 to 688 ± 10.1 cfu∙g-1 (U samples). The nutritional parameters (moisture, ash, water activity, pH, total acidity, protein, fiber, total phenolic, flavonoids and reducing sugars) were within the stipulated by law, except for pH and moisture content, which presented superior and inferior values, respectively. Polyunsaturated fatty acids (54.1%) were significantly higher than saturated (42.18%) and monounsaturated (3.71%). It was found that the bee pollen is safe from the microbiological point of view and has a good nutritional quality. The influence of the geographical origin on the assessed parameters was evident, especially concerning the fatty acid profile.

Bees for development: Brazilian survey reveals how to optimize stingless beekeeping.

Stingless bees are an important asset to assure plant biodiversity in many natural ecosystems, and fulfill the growing agricultural demand for pollination. However, across developing countries stingless beekeeping remains an essentially informal activity, technical knowledge is scarce, and management practices lack standardization. Here we profited from the large diversity of stingless beekeepers found in Brazil to assess the impact of particular management practices on productivity and economic revenues from the commercialization of stingless bee products. Our study represents the first large-scale effort aiming at optimizing stingless beekeeping for honey/colony production based on quantitative data. Survey data from 251 beekeepers scattered across 20 Brazilian States revealed the influence of specific management practices and other confounding factors over productivity and income indicators. Specifically, our results highlight the importance of teaching beekeepers how to inspect and feed their colonies, how to multiply them and keep track of genetic lineages, how to harvest and preserve the honey, how to use vinegar traps to control infestation by parasitic flies, and how to add value by labeling honey containers. Furthermore, beekeeping experience and the network of known beekeepers were found to be key factors influencing productivity and income. Our work provides clear guidelines to optimize stingless beekeeping and help transform the activity into a powerful tool for sustainable development.