BackgroundThe implementation of new public healthcare models that stimulate the use of natural products from traditional medicine, as a so-called integrated medicine, refers to an approach that use best of both conventional medicine and traditional medicine. Propolis is a widely used natural product by different ancient cultures and known to exhibit biological activities beneficial for health. The large number of studies conducted with propolis had shown that its chemical composition differs as a function of the climate, plant diversity and bee species and plays an important role on its therapeutic properties. The aim of this study was to analyse the phytochemical profile of the ethanolic extract of red propolis (EEP) and its fractionation, antioxidant action of EEP and its fractions hexane, cloroform and ethyl acetate and cytotoxic activity of EEP on human tumour cell lines SF-295 (glioblastoma), OVCAR-8 (ovary) and HCT-116 (colon).MethodsEEP was obtained by maceration with absolute ethanol, then it was concentrated in rotaevaporator up to complete evaporation of the solvent. The crude extract was fractionated with hexane, ethyl acetate, chloroform and methanol and they were subjected to phytochemical screening and total phenolic compounds. Antioxidant activity of EEP and fractions was done by means of the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. Biomarkers of red propolis were identified by LC-Orbitrap-FTMS. To assess cytotoxic activity of the extract, cells were exposed to EEP over 72 h. Cell viability was assessed by means of MTT assay. The percentage of cell growth inhibition (IC50) was analysed by means of non-linear regression, and the absorbance values of the various investigated concentrations were subjected to one-factor analysis of variance (ANOVA) followed by Tukey’s or Tamhane’s tests (α = 0.05).ResultsThe results obtained using phytochemical screening and LC-Orbitrap-FTMS indicated the presence of phlobaphene tannins, catechins, chalcones, aurones, flavonones, flavonols, xanthones, pentacyclic triterpenoids and guttiferones in Brazilian red propolis. EEP and its hexane, chloroform and ethyl acetate fractions obtained by liquid-liquid partitioning exhibited satisfactory antioxidant percentages. EEP (IC50 < 34.27 μg/mL) exhibited high levels of cytotoxicity on all human tumour cell lines tested when compared to negative control.ConclusionsC-Orbitrap-FTMS was useful to establish the chemical profile of the red propolis. Brazilian red propolis has antioxidant properties and decreases substantially the percentage of cell survival of human tumour cells; thus, it has potential to serve as an anticancer drug.

The ever-increasing demand for natural products and biotechnology derived from bees and ultra-modernization of various analytical devices has facilitated the rational and planned development of biotechnology products with a focus on human health to treat chronic and neglected diseases. The aim of the present study was to prepare and characterize polymeric nanoparticles loaded with Brazilian red propolis extract and evaluate the cytotoxic activity of “multiple-constituent extract in co-delivery system” for antileishmanial therapies. The polymeric nanoparticles loaded with red propolis extract were prepared with a combination of poly-ε-caprolactone and pluronic using nanoprecipitation method and characterized by different analytical techniques, antioxidant and leishmanicidal assay. The red propolis nanoparticles in aqueous medium presented particle size (200–280 nm) in nanometric scale and zeta analysis (−20 to −26 mV) revealed stability of the nanoparticles without aggregation phenomenon during 1 month. After freeze-drying method using cryoprotectant (sodium starch glycolate), it was possible to observe particles with smooth and spherical shape and apparent size of 200 to 400 nm. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and thermal analysis revealed the encapsulation of the flavonoids from the red propolis extract into the polymeric matrix. Ultra performance liquid chromatography coupled with diode array detector (UPLC-DAD) identified the flavonoids liquiritigenin, pinobanksin, isoliquiritigenin, formononetin and biochanin A in ethanolic extract of propolis (EEP) and nanoparticles of red propolis extract (NRPE). The efficiency of encapsulation was determinate, and median values (75.0 %) were calculated using UPLC-DAD. 2,2-Diphenyl-1-picryhydrazyl method showed antioxidant activity to EEP and red propolis nanoparticles. Compared to negative control, EEP and NRPE exhibited leishmanicidal activity with an IC50 value of ≅38.0 μg/mL and 31.3 μg/mL, 47.2 μg/mL, 154.2μg/mL and 193.2 μg/mL for NRPE A1, NRPE A2, NRPE A3 and NRPE A4, respectively. Nanoparticles loaded with red propolis extract in co-delivery system and EEP presented cytotoxic activity on Leishmania (V.) braziliensis. Red propolis extract loaded in nanoparticles has shown to be potential candidates as intermediate products for preparation of various pharmaceutical dosage forms containing red propolis extract in the therapy against negligible diseases such as leishmaniasis.Graphical AbstractSome biochemical mechanisms of cellular debridement of Leishmania (V.) braziliensis species by the flavonoids of red propolis extract (EEP) or NRPE loaded with red propolis extractElectronic supplementary materialThe online version of this article (doi:10.1186/s11671-016-1517-3) contains supplementary material, which is available to authorized users.

Coral-algal symbiosis has been a subject of great attention during the last two decades in response to global coral reef decline. However, the occurrence and dispersion of free-living dinoflagellates belonging to the genus Symbiodinium are less documented. Here ecological and molecular evidence is presented demonstrating the existence of demersal free-living Symbiodinium populations in Caribbean reefs and the possible role of the stoplight parrotfish (Sparisoma viride) as Symbiodinium spp. dispersers. Communities of free-living Symbiodinium were found within macroalgal beds consisting of Halimeda spp., Lobophora variegata, Amphiroa spp., Caulerpa spp. and Dictyota spp. Viable Symbiodinium spp. cells were isolated and cultured from macroalgal beds and S. viride feces. Further identification of Symbiodinium spp. type was determined by length variation in the Internal Transcribed Spacer 2 (ITS2, nuclear rDNA) and length variation in domain V of the chloroplast large subunit ribosomal DNA (cp23S-rDNA). Determination of free-living Symbiodinium and mechanisms of dispersal is important in understanding the life cycle of Symbiodinium spp.

The standardization of apiceutical products like as propolis extracts has been widely debated worldwide and variations in the propolis chemical composition are still very relevant topics for use-standardized of different propolis-type as medication by much of the world’s population. The present manuscript discuss important issues related to the climate effect and variations in propolis metabolite-profiling changes, antioxidant capacity and variations of the antibacterial activity of the Brazilian red propolis metabolites using comprehensive multivariate correlations. It was observed the increasing of guttiferones concentrations during the intense drought period and drastic decreasing in rainy period. The climate variation induced the high concentration of flavonoids in rainy period with pronounced dropped in some rainy months. The Pearson´s analysis demonstrated correlation between IC50 from DPPH and guttiferones and flavonoids concentrations. The PCA-X and Hotelling T2 test showed outliers during the months with lowest concentrations of formononetin and isoliquiritigenin was observed in antibacterial tests. The PLS-DA, OPLS-DA and VIP analysis demonstrate guttiferone E, guttiferone B, liquiritigenin, naringenin are considered important substances responsible by anti-staphylococcal activity in red propolis composition during the rainy season and drought period, but a synergistic effect with other flavonoids and isoflavonoids are not ruled out.

Matrix metalloproteinases (MMPs) are enzymes that can degrade collagen in hybrid layer and reduce the longevity of adhesive restorations. As scientific understanding of the MMPs has advanced, useful strategies focusing on preventing these enzymes' actions by MMP inhibitors have quickly developed in many medical fields. However, in restorative dentistry, it is still not well established. This paper is an overview of the strategies to inhibit MMPs that can achieve a long-lasting material-tooth adhesion. Literature search was performed comprehensively using the electronic databases: PubMed, ScienceDirect and Scopus including articles from May 2007 to December 2019 and the main search terms were "matrix metalloproteinases", "collagen", and "dentin" and "hybrid layer". MMPs typical structure consists of several distinct domains. MMP inhibitors can be divided into 2 main groups: synthetic (syntheticpeptides, non-peptide molecules and compounds, tetracyclines, metallic ions, and others) and natural bioactive inhibitors mainly flavonoids. Selective inhibitors of MMPs promise to be the future for specific targeting of preventing dentin proteolysis. The knowledge about MMPs functionality should be considered to synthesize drugs capable to efficiently and selectively block MMPs chemical routes targeting their inactivation in order to overcome the current limitations of the therapeutic use of MMPs inhibitors, i.e., easy clinical application and long-lasting effect.