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Propolis has been considered a resinous substance with a complex chemical composition that is collected from several plant species by Apis mellifera bees, and used by man as an alternative to the healing of diseases and to keep a good health. The chemical composition of propolis is related to the biodiversity of the region visited by the bees and also to the season of collection. This research purpose was to optimize the production methodology of ethanol extract of propolis and to evaluate the effect of seasonality in the chemical composition and biological activities of this product. Samples of propolis were collected from the apiary at the Federal Institute of Education, Science and Technology of the South of Minas Gerais - Campus Muzambinho and were used to make ethanol extracts. In the optimization stage, ethanolic solutions in different concentrations and different extraction and drying temperatures were used. For the analysis of the seasonal effect, propolis was collected from the same place in different seasons. The results showed that the 80% ethanolic solution and the extraction temperature of 70ºC and drying at 45ºC were the ones that stood out the most. Regarding the effect of seasonality on the chemical composition and biological activities of propolis, it is clear that there are differences between the propolis collected in different seasons.

Abstract Brown propolis from permanent preservation and reforestation areas of southern Brazil have attracted international commercial interest and have a unique composition, although little is known about their botanical origins, which are the plant resins used by bee foragers to produce propolis. Hence, the volatile profiles of organic and non-organic brown propolis and resins of suspected botanical origins—Araucaria angustifolia, Pinus elliott and Pinus taeda—were determined using static headspace gas chromatography coupled to mass spectrometry (SHS-GCMS) and compared. Nighty nine volatiles were tentatively identified, and monoterpenes and sesquiterpenes were the most abundant classes. Principal component analysis (PCA) showed similarity between organic propolis and A. angustifolia volatile profiles (p

This paper describes the construction and characterization of a biofuel cell with low-cost materials. The system uses the baker’s yeast (Saccharomyces cerevisiae) as the microorganism responsible for the generation of voltage, whose interaction with the electrode is mediated by methylene blue. Simple experiments are proposed to evaluate the effects of different substrates, inhibitors and cell viability, improving both the knowledge of the system as well as metabolic pathway concepts to the student. The proposed device was able to generate a power density of 41 ± 0.3 mW m−2, similar to those obtained with yeast-based biofuel cells. The low cost and easily acquisition of materials described allow the introduction of biofuel cell theme in different teaching levels, from high school to the college level.

Brazilian red propolis (BRP) is a natural product widely known for its phenolic composition and strong antioxidant properties. In this study, we used the Box–Behnken Design (BBD) with Surface Response Methodology to optimize the extraction conditions for total phenolic content (TPC) and Trolox equivalent antioxidant capacity(TEAC) of bioactive phenolics from BRP. The extraction time, ethanol/water concentration and temperature, were tested. All variables had significant effects (p ≤ 0.05), with a desirability coefficient of 0.88. Under optimized conditions (90% ethanol at 80 °C for 30 min), the BRP extract showed a TPC of 129.00 ± 2.16 mg GAE/g and a TEAC of 3471.76 ± 53.86 µmol TE/g. Moreover, FRAP and ORAC assays revealed that the optimized BRP extract had 1472.86 ± 72.37 µmol Fe2+/g and 4339.61 ± 114.65 µmol TE/gof dry weight, respectively. Thirty-two phenolic compounds were tentatively identified by LC-QTOF-ESI-MS/MS, of which thirteen were found for the first time in BRP, including four flavones, one flavanol, two flavanones, two chalcones, and four isoflavonoids. Thus, our results highlight the importance of BRP as a source of a wide variety of phenolic compounds with significant antioxidant properties.

ent-Nemorosone is a benzophenone isolated from geopropolis from Melipona scutellaris whose biological properties remain unexplored. Herein, we evaluated the anti-inflammatory activity of ent-nemorosone by in vivo neutrophil migration and TNF-α quantification, as well as by in vitro TNF-α quantification, ERK 1/2 phosphorylation, NF-kB activation and nuclear translocation of p65 in stimulated macrophages. ent-Nemorosone was also tested for its antimicrobial effects against Streptococcus mutans biofilm adhesion, polysaccharide production, and viability. ent-Nemorosone reduced the influx of neutrophils and TNF-α release into the peritoneal cavity of mice, as well as the in vitro TNF-α levels, ERK 1/2 phosphorylation, NF-kB activation and nuclear p65 translocation. Furthermore, this compound inhibited biofilm adhesion and reduced the amount of extra- and intracellular polysaccharides synthesized by S. mutans. Thus, ent-nemorosone showed promising anti-inflammatory activity by acting on TNF-α release in macrophages, as well as anti-biofilm properties by reducing S. mutans polysaccharide production.

South Brazilian organic propolis (OP), which has never been studied before, was assessed and its chemical composition, scavenging potential of reactive oxygen species, antimicrobial and anti-inflammatory activities are herein presented. Based on the chemical profile obtained using HPLC, OP was grouped into seven variants (OP1-OP7) and all of them exhibited high scavenging activity, mainly against superoxide and hypochlorous acid species. OP1, OP2, and OP3 had the smallest minimal inhibitory concentration (MIC) against Gram-positive bacteria Streptococcus mutans, Streptococcus oralis, and Streptococcus aureus (12.5-100 μg/mL). OP1, OP2, OP3, and OP4 were more effective against Pseudomonas aeruginosa (Gram-negative), with MIC values ranging from 100 to 200 μg/mL. OP6 showed anti-inflammatory activity by decreasing NF-kB activation and TNF-α release in RAW 264.7 macrophages, and expressing the NF-κB-luciferase reporter stable gene. Therefore, south Brazilian OP can be considered an excellent source of bioactive compounds with great potential of application in the pharmaceutical and food industry.

Biological assays that have been performed on different types of Brazilian propolis have shown that type 6 propolis (G6) has a strong antimicrobial activity and a low flavonoid content. This study aimed to evaluate the correlation between the phenolic composition and the biological activities displayed by propolis G6 from the state of Bahia and green propolis, also known as type 12 (G12). The values of the flavonoids and the total phenolics in propolis G6 were different than those in propolis G12. Although the G12 variety presented greater antioxidant activity, propolis G6 proved to have greater antimicrobial and cytotoxic activities. The results showed that the phenolic compounds may not be the only compounds responsible for the biological activity. More detailed studies of the chemical composition and an assessment of the biological activity are required to establish the quality of propolis.Ensaios biológicos realizados com diferentes tipos de própolis brasileira têm mostrado que a própolis do tipo 6 (G6) tem forte atividade antimicrobiana e menor teor de flavonóides. Este trabalho teve como objetivo avaliar a correlação entre a composição fenólica e atividades biológicas apresentadas pela própolis G6, do Estado da Bahia, e a própolis verde, do tipo 12 (G12). Os teores de flavonóides e fenólicos totais na própolis G6 foram diferentes dos teores da própolis G12. Apesar da G12 apresentar maior atividade antioxidante, a própolis G6 apresenta maior atividade antimicrobiana e citotóxica. Os resultados mostraram que os compostos fenólicos não são os únicos compostos responsáveis pela atividade biológica da própolis. Estudos mais específicos da composição química, em adição à avaliação das atividades biológicas, são requeridos para determinar a qualidade da própolis.

A total of 22 endophytic fungi isolated from coffee (Coffea arabica L.) were cultivated in vitro and their crude extracts tested. The screening was carried out using the agar diffusion method against Staphylococcus aureus, Escherichia coli and Candida albicans. The most effective isolate was Alternaria alternata, and subsequently, its extract was assayed. The total phenolic content was 3.44 μg GAE/mg of the crude extract. For the antibacterial and antifungal activity assays, minimum inhibitory concentrations (MIC) and minimum bactericidal and fungicidal concentrations (MBC and MFC) were determined. The ranges of MIC values were 50-100 μg/mL for S. aureus and 400-800 μg/mL for E. coli. The extract did not show activity in the tested concentrations for C. albicans. The fungal crude extract was assayed for antioxidant activities. Its ability to scavenge DPPH radicals and antioxidant activity by β-carotene/linoleic acid system oxidation was not significant. In addition, antitumor activity was studied using the MTT assay. At a dilution of 400 μg/mL, the extract displayed a cytotoxic activity of approximately 50% towards HeLa cells in vitro. The results indicate that endophytic fungi could be a promising source of bioactive compounds and warrant further study.Total de 22 fungos endofíticos isolados de café (Coffea arabica L.) foi cultivado in vitro e seus extratos testados. A triagem foi conduzida pelo método de difusão em agar contra bactérias Gram-positiva, Gram-negativa e uma levedura. O isolado mais efetivo foi Alternaria alternata e, subsequentemente, seu extrato foi analisado. O conteúdo de fenólicos totais do extrato bruto foi de 3,44 μg EAG/mg de extrato. Para os testes de atividade antimicrobiana, a concentração inibitória mínima (CIM) e concentração bactericida e fungicida mínima (CBM e CFM) contra Staphylococcus aureus, Escherichia coli e Candida albicans foram determinadas. Resultados da CIM variaram entre 50-100 μg/mL para S. aureus e 400-800 μg/mL para E. coli. O extrato bruto não apresentou atividade nas concentrações testadas para C. albicans. Foram analisadas as atividades antioxidantes do extrato bruto. Sua habilidade para seqüestrar radicais DPPH e a atividade antioxidante pela oxidação do sistema β-caroteno/ácido linoléico não foram significativas. Além disso, a atividade antitumoral foi estudada pelo teste do MTT. À diluição de 400 μg/mL, o extrato apresentou atividade de aproximadamente 50% sobre as células HeLa in vitro. Os resultados indicam que fungos endófitos poderiam ser uma fonte promissora de compostos bioativos necessitando de estudos futuros.

Propolis is a resinous hive product collected by honeybees from various plant sources. It has a complex chemical composition, constituted by various phenolic compounds. Extracts of increasing polarity (n-hexane, chloroform, and ethanol) were obtained from a sample of red propolis from the state of Alagoas. Assays were carried out for determination of contents of phenolics, along with antibacterial and antioxidant activities. The EEP, fractions and sub-fractions showed strong biological activities and were related with phenolic the content compounds contents. The sub-fractions were more bioactive than the EEP and fractions, demonstrating that the antioxidant and antibacterial activities are not a result of synergistic effect between the various chemical compounds in propolis.

The composition and biological activities of propolis, a resinous hive product collected by honeybees from various plant sources, depends on various factors such as season and vegetation of the area. The aim of this study was to evaluate the influence of the seasonal effect on the ethanolic extracts of Brazilian propolis (EEP) type 6 and type 12, collected during 6 months in terms of antibacterial activity and phenolic composition. The antimicrobial properties were evaluated by MIC and MBC on S. mutans Ingbritt 1600 and the profile of chemical composition by UV-visible spectrophotometry, HPLC-RF and GC-MS. The results demonstrated that the season in which propolis is collected influences its chemical composition, resulting in modifications in its antibacterial activity.

Cryptococcosis is a worldwide disease caused by the etiological agent Cryptococcus neoformans. It affects mainly immunocompromised humans. It is relatively rare in animals only affecting those that have received prolonged antibiotic therapy. The propolis is a resin that can present several biological properties, including antibacterial, antifungal and antiviral activities. The standard strain C. neoformans ATTC 90112 was used to the antifungal evaluation. The tests were realized with propolis ethanol extract (PEE) G12 in concentrations from 0.1 to 1.6 mg mL-1. The evaluation of MIC and MFC were done according to DUARTE (2002)5. The inhibitory effect of PEE G12 on the fungal growing was seen at the concentration of 0.2 mg mL-1 and 1.6 mg mL-1 was considered a fungicidal one.Criptococose, doença cosmopolita, causada pelo agente etiológico Cryptococcus neoformans, está associada, principalmente, a indivíduos imunocomprometidos. O acometimento de animais é relativamente raro, exceto, nos casos associados à prolongada antibioticoterapia. A própolis é uma resina que pode apresentar diversas propriedades biológicas, incluindo atividades antibacterianas, antifúngicas e antivirais. Amostra padrão de C. neoformans foi utilizada no teste de atividade antifúngica do extrato etanólico de própolis (EEP) G12 nas concentrações de 0,1 a 1,6 mg.mL-1. As avaliações da Concentração Inibitória Mínima (CIM) e Concentração Fungicida Mínima (CFM) foram realizadas conforme DUARTE5. O efeito inibitório do EEP G12 sobre o crescimento fúngico foi observado na concentração de 0,2 mg.mL-1. A concentração de 1,6 mg.mL-1 foi considerada fungicida.