ANÁLISE ANTIMICROBIANA DO LÚPULO (HUMULUS LUPULUS) EM MOSTO CERVEJEIRO

O lúpulo (Humulus lupulus) é uma planta trepadeira perene dioica, da família Cannabaceae, cujas inflorescências femininas apresentam glândulas lupulina responsáveis pela produção de resinas (que conferem amargor), polifenóis (com propriedades antioxidantes) e óleos essenciais (que conferem aroma) que despertam grande interesse na produção de cerveja. Apesar de ser considerado ingrediente fundamental na produção da cerveja devido às propriedades organolépticas oferecidas ao produto, acredita-se que utilização inicial do lúpulo na produção de cerveja deve-se às suas propriedades microbiológicas e farmacológicas, já sendo comprovado que os ácidos contidos no lúpulo interferem no transporte de metabólitos na membrana celular, modificando o pH intracelular, o que provoca morte das bactérias, principalmente em bactérias Gram-positivas, Sendo assim, o presente trabalho consiste na análise antibacteriana do Humulus lupulus, em diferentes concentrações em mosto cervejeiro, sobre bactérias do gênero Lactobacillus, sendo quatro delas resistentes à cerveja e, uma levedura selvagem Brettanomyces lambicus, isolada de cervejaria pela empresa Levteck. Inicialmente, foi avaliado a ação do lúpulo Amarillo, por meio da técnica de disco-difusão em ágar. Para tal, foram produzidos 5 Litros de mosto utilizando-se 1,02 kg Malte Pale Ale e 0,03 kg de Malte Chateau Crystal. O malte previamente moído foi adicionado em água aquecida a 67°C, por uma hora para a liberação dos açúcares fermentescíveis e depois, por 10 minutos a 77°C, para a inativação das enzimas, processo conhecido como mash out. Após a lavagem do malte, o mosto recebeu diferentes concentrações do lúpulo Amarillo, e foi novamente aquecido a 92°C por uma hora. Após o processo de fervura do mosto, foi realizado whirlpool para decantação de sedimentos e essa solução foi utilizada para a avaliação da ação antimicrobiana. As bactérias foram reativadas por meio de repiques sucessivos em caldo MRS, mantidas em estufas bacteriológicas, por 24 horas a 37±3 ºC e quantificadas pela técnica de pour plate em triplicatas. Até o presente momento foi realizado somente um teste de avaliação não permitindo resultados conclusivos. As análises serão repetidas para melhor elucidar a concentração mínima inibitória de lúpulo no mosto capaz de promover inibição das bactérias lácticas, principais contaminantes da cerveja

A vision for safer food contact materials: Public health concerns as drivers for improved testing

Food contact materials (FCMs) and food contact articles are ubiquitous in today's globalized food system. Chemicals migrate from FCMs into foodstuffs, so called food contact chemicals (FCCs), but current regulatory requirements do not sufficiently protect public health from hazardous FCCs because only individual substances used to make FCMs are tested and mostly only for genotoxicity while endocrine disruption and other hazard properties are disregarded. Indeed, FCMs are a known source of a wide range of hazardous chemicals, and they likely contribute to highly prevalent non-communicable diseases. FCMs can also include non-intentionally added substances (NIAS), which often are unknown and therefore not subject to risk assessment. To address these important shortcomings, we outline how the safety of FCMs may be improved by (1) testing the overall migrate, including (unknown) NIAS, of finished food contact articles, and (2) expanding toxicological testing beyond genotoxicity to multiple endpoints associated with non-communicable diseases relevant to human health. To identify mechanistic endpoints for testing, we group chronic health outcomes associated with chemical exposure into Six Clusters of Disease (SCOD) and we propose that finished food contact articles should be tested for their impacts on these SCOD. Research should focus on developing robust, relevant, and sensitive in-vitro assays based on mechanistic information linked to the SCOD, e.g., through Adverse Outcome Pathways (AOPs) or Key Characteristics of Toxicants. Implementing this vision will improve prevention of chronic diseases that are associated with hazardous chemical exposures, including from FCMs

Gα_i Proteins are Indispensable for Hearing

Background/Aims: From invertebrates to mammals, Gαi proteins act together with their common binding partner Gpsm2 to govern cell polarization and planar organization in virtually any polarized cell. Recently, we demonstrated that Gαi3-deficiency in pre-hearing murine cochleae pointed to a role of Gαi3 for asymmetric migration of the kinocilium as well as the orientation and shape of the stereociliary (“hair”) bundle, a requirement for the progression of mature hearing. We found that the lack of Gαi3 impairs stereociliary elongation and hair bundle shape in high-frequency cochlear regions, linked to elevated hearing thresholds for high-frequency sound. How these morphological defects translate into hearing phenotypes is not clear. Methods: Here, we studied global and conditional Gnai3 and Gnai2 mouse mutants deficient for either one or both Gαi proteins. Comparative analyses of global versus Foxg1-driven conditional mutants that mainly delete in the inner ear and telencephalon in combination with functional tests were applied to dissect essential and redundant functions of different Gαi isoforms and to assign specific defects to outer or inner hair cells, the auditory nerve, satellite cells or central auditory neurons. Results: Here we report that lack of Gαi3 but not of the ubiquitously expressed Gαi2 elevates hearing threshold, accompanied by impaired hair bundle elongation and shape in high-frequency cochlear regions. During the crucial reprogramming of the immature inner hair cell (IHC) synapse into a functional sensory synapse of the mature IHC deficiency for Gαi2 or Gαi3 had no impact. In contrast, double-deficiency for Gαi2 and Gαi3 isoforms results in abnormalities along the entire tonotopic axis including profound deafness associated with stereocilia defects. In these mice, postnatal IHC synapse maturation is also impaired. In addition, the analysis of conditional versus global Gαi3-deficient mice revealed that the amplitude of ABR wave IV was disproportionally elevated in comparison to ABR wave I indicating that Gαi3 is selectively involved in generation of neural gain during auditory processing. Conclusion: We propose a so far unrecognized complexity of isoform-specific and overlapping Gαi protein functions particular during final differentiation processes

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements