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Stingrays skin secretions are largely studied due to the human envenoming medical relevance of the sting puncture that evolves to inflammatory events, including necrosis. Such toxic effects can be correlated to the biochemical composition of the sting mucus, according to the literature. Fish skin plays important biological roles, such as the control of the osmotic pressure gradient, protection against mechanical forces and microorganism infections. The mucus, on the other hand, is a rich and complex fluid, acting on swimming, nutrition and the innate immune system. The elasmobranch's epidermis is a tissue composed mainly by mucus secretory cells, and marine stingrays have already been described to present secretory glands spread throughout the body. Little is known about the biochemical composition of the stingray mucus, but recent studies have corroborated the importance of mucus in the envenomation process. Aiming to assess the mucus composition, a new non-invasive mucus collection method was developed that focused on peptides and proteins, and biological assays were performed to analyze the toxic and immune activities of the Hypanus americanus mucus. Pathophysiological characterization showed the presence of peptidases on the mucus, as well as the induction of edema and leukocyte recruitment in mice. The fractionated mucus improved phagocytosis on macrophages and showed antimicrobial activity against T. rubrumç. neoformans and C. albicans in vitro. The proteomic analyses showed the presence of immune-related proteins like actin, histones, hemoglobin, and ribosomal proteins. This protein pattern is similar to those reported for other fish mucus and stingray venoms. This is the first report depicting the Hypanus stingray mucus composition, highlighting its biochemical composition and importance for the stingray immune system and the possible role on the envenomation process.

Background Naja mandalayensis is a spitting cobra from Myanmar. To the best of our knowledge, no studies on this venom composition have been conducted so far. On the other hand, few envenomation descriptions state that it elicits mainly local inflammation in the victims’ eyes, the preferred target of this spiting cobra. Symptoms would typically include burning and painful sensation, conjunctivitis, edema and temporary loss of vision. Methods We have performed a liquid-chromatography (C18-RP-HPLC) mass spectrometry (ESI-IT-TOF/MS) based approach in order to biochemically characterize N. mandalayensis venom. Results A wide variety of three-finger toxins (cardiotoxins) and metallopeptidases were detected. Less abundant, but still representative, were cysteine-rich secretory proteins, L-amino-acid oxidases, phospholipases A2, venom 5'-nucleotidase and a serine peptidase inhibitor. Other proteins were present, but were detected in a relatively small concentration. Conclusion The present study set the basis for a better comprehension of the envenomation from a molecular perspective and, by increasing the interest and information available for this species, allows future venom comparisons among cobras and their diverse venom proteins.

The propolis produced by stingless bees of the tribe Meliponini is a viscous product that contains the resin collected from buds, leaves and plant exudates, mixed with salivary secretions, wax and soil. The species Scaptotrigona aff. postica (Latreille, 1807), (Hymenoptera, Apidae, Meliponinae) popularly known as “tubi” in Maranhão State, Brazil, does not mix soil to produce its propolis. The propolis from S. postica harvested in Barra do Corda, Maranhão State, is popularly used in the treatment of wounds and respiratory illnesses. The hydroalcoholic extract of this propolis, rich in flavone-6,8-di-C-glycosides (vicenin-2 and schaftoside), pyrrolizidine alkaloids derived from retronecine, catechin and caffeoylquinic acid derivatives exhibited antiviral activity against the herpes simplex and rubella viruses. The aim of this study was to increase knowledge about the chemical composition of the S. postica propolis by analyzing non-polar extracts obtained using hexane and chloroform as the solvents, by GC-EI-MS. A total of 15 constituents were identified comparing their respective mass spectral data with those available in the NIST data bases and those reported in the literature. The main constituents detected were the phenolic lipids, known as cardanols, 3-(4,7-heptadecadienyl) phenol (5), 3-(10-heptadecenyl) phenol (7), 3-heptadecylphenol (9) and 3-pentadecyl phenol or hydrocardanol (13), which predominated in the hexane extract, while the predominant constituents in the chloroform extract were 3-pentadecyl phenol or hydrocardanol (13) and 3-(8-pentadecenyl) phenol (12). The antioxidant, antitumoral, antifeedant, cytotoxic, anticarcinogenic, antiproliferative, antimicrobial, antileishmanial and larvicidal activities of the cardanols have been demonstrated in many studies. Resumo A própolis elaborada pelas abelhas sem ferrão (Apidae, Meliponini) é um material resinoso extraído de brotos, folhas e exsudatos de plantas, que são misturados com secreções salivares, cera e solo. A espécie Scaptotrigona aff. postica (Latreille, 1807), (Hymenoptera, Apidae, Meliponini), popularmente conhecida como “tubi”, no estado do Maranhão, não mistura solo na produção da própolis. A própolis de S. postica coletada no município de Barra do Corda, estado do Maranhão, é usada popularmente no tratamento de feridas e doenças respiratórias. O extrato hidroalcoólico desta própolis é rico em flavonas-6,8- C -glicosídeos (vicenina e schaftosídeo), alcaloides pirrolizidínicos, catequinas e ácidos cafeoilquínicos, e mostrou atividade antiviral contra os vírus do herpes e da rubéola. O objetivo deste estudo foi ampliar o conhecimento sobre a composição química da própolis de S. postica, analisando os extratos apolares obtidos usando hexano e clorofórmio como solventes, por cromatografia gasosa acoplada a espectrometria de massas. Os 15 constituintes detectados foram identificados comparando os seus respectivos espectros de massas com espectros de massas compilados nas bases de dados NIST e reportados na literatura. Os principais constituintes encontrados foram os lipídios fenólicos, conhecidos como cardanóis, 3-(4,7-heptadecadienil) fenol (5), 3-(10-heptadecenil) fenol (7), 3-heptadecilfenol (9) e 3-pentadecilfenol ou hidrocarbônico (13), que predominaram no extrato hexânico, enquanto que, no extrato clorofórmico, os constituintes predominantes foram 3-pentadecilfenol ou hidrocarbônico (13) e 3-(8-pentadecenil) fenol (12). As atividades antioxidante, antitumoral, citotóxica, antiproliferativa e larvicida dos cardanóis foram demonstradas através de vários estudos.

The search for functional foods, which possess bioactive substances, is a new trend for the obtention of alternative and more effective treatments of many diseases with fewer side effects. Geopropolis, elaborated by stingless bees, is a mixture of plant resin sources, wax and soil. In the geopropolis from Scaptotrigona affinis postica (Latreille, 1807), (Hymenoptera, Apidae, Meliponini) was not observed the presence of soil. In a previous study, the extract of geopropolis provided by the beekeeper, from S. postica of Barra do Corda, Maranhão State, exhibited potent antiviral activity against herpes simplex virus. In this study, the propolis extract was prepared experimentally and characterized by RP-HPLC-DAD-ESI-MS/MS. The objective of this study was to evaluate the antiviral activity of an experimentally prepared geopropolis extract from S. postica against Rubella Virus infected Statens Serum Institute Rabbit Cornea (SIRC) cells. Rubella virus infection of susceptible women during the first trimester of pregnancy, often results in a combination of birth defects in newborns. There is not an effective treatment for rubella virus infection. Different protocols were carried out to evaluate, the antiviral effect of geopropolis extract on the viral replication of infectious RV. Cell viability and cell proliferation assays indicated that this geopropolis was not toxic to cultured SIRC cells. In the viral binding assay, antiviral assay, real-time PCR, and transmission electron microscopy, was observed that different concentrations of geopropolis (17, 34 and 68 µg/mL) was able to inhibit the binding of virions to the cell receptor and the production of infectious RV particles in post treated and pre treated infected SIRC cells. The antiviral activity could to be attributed to the high contents of the apigenin derivatives, vicenin-2 and schaftoside. As far as we know, this is the first report about the antiviral activity of geopropolis from Scaptotrigona postica against a Togaviridae virus.

The studies on chemical composition and biological activity of propolis had focused mainly on speciesApis melliferaL. (Hymenoptera: Apidae). There are few studies about the uncommon propolis collected by stingless bees of the Meliponini tribe known as geopropolis. The geopropolis fromScaptotrigona posticawas collected in the region of Barra do Corda, Maranhão state, Brazil. The chemical analysis of hydromethanolic extract of this geopropolis (HMG) was carried out through HPLC-DAD-ESI-MS/MS and the main constituents found were pyrrolizidine alkaloids and C-glycosyl flavones. The presence of alkaloids in extracts of propolis is detected for the first time in this sample. The antiviral activity of HMG was evaluated through viral DNA quantification experiments and electron microscopy experiments. Quantification of viral DNA from herpes virus showed reduction of about 98% in all conditions and concentration tested of the HMG extract. The results obtained were corroborated by transmission electron microscopy, in which the images did not show particle or viral replication complex. The antiviral activity of C-glycosyl flavones was reported for a variety of viruses, being observed at different points in the viral replication. This work is the first report about the antiviral activity of geopropolis fromScaptotrigona postica, in vitro, against antiherpes simplex virus (HSV).