RESUMEN
Nannochloropsis oculata is naturally rich in eicosapentaenoic acid (EPA). To turn this microalga into an economically viable source for commercial applications, extraction efficiency must be achieved. Pursuing this goal, emerging technologies such as high hydrostatic pressure (HHP) and moderate electric fields (MEF) were tested, aiming to increase EPA accessibility and subsequent extraction yields. The innovative approach used in this study combined these technologies and associated tailored, less hazardous different solvent mixtures (SM) with distinct polarity indexes. Although the classical Folch SM with chloroform: methanol (PI 4.4) provided the highest yield concerning total lipids (166.4 mglipid/gbiomass), diethyl ether: ethanol (PI 3.6) presented statistically higher values in terms of EPA per biomass, corresponding to 1.3-fold increase. When SM were used in HHP and MEF, neither technology independently improved EPA extraction yields, although the sequential combination of technologies did result in 62% increment in EPA extraction. Overall, the SM and extraction methodologies tested (HHP-200 MPa, 21 °C, 15 min, followed by MEF processing at 40 °C, 15 min) enabled increased EPA extraction yields from wet N. oculata biomass. These findings are of high relevance for the food and pharmaceutical industries, providing viable alternatives to the "classical" extraction methodologies and solvents, with increased yields and lower environmental impact. KEY POINTS: ⢠Et2O: EtOH is a less toxic and more efficient alternative to Folch solvent mixture ⢠HHP or MEF per se was not able to significantly increase EPA extraction yield ⢠Combinations of HHP and MEF technologies increased both lipids and EPA yields.
Asunto(s)
Microalgas , Estramenopilos , Ácido Eicosapentaenoico , Solventes , Metanol , Etanol , BiomasaRESUMEN
Two environmental parameters, temperature and light intensity, were independently used as stress modulators to enhance eicosapentaenoic acid (EPA) production by the microalga Nannochloropsis oculata, without hindering biomass production. A sinusoidal approach was used, as environmental conditions were alternated between optimum and stress status in multi-day cycles. Low temperatures (5 and 10 °C) and light intensities (30 and 50 µmol photons/m2/s) were tested. Results revealed that the modulated stress approach used was able to avoid decreases in biomass production. Temperature stress (10 °C) presented the highest impact, increasing EPA content to 12.8 mgEPA/L, 158% more than the amount obtained in optimum (non-modulated) growth conditions at that point in time, while the lower light intensity stress was able to increase to 126% more. It is important to point out that in both cases increases in EPA amounts resulted from increased content in each individual cell and not just from increased biomass contents. KEY POINTS: ⢠Temperature stress (10 °C) presented the highest impact increasing EPA content 158% ⢠Lower light intensity stress was able to increase EPA to 126% more ⢠EPA increased in individual cell contents simultaneous with biomass increase.
Asunto(s)
Microalgas , Estramenopilos , Biomasa , Ácido Eicosapentaenoico , TemperaturaRESUMEN
Nannochloropsis oculata is well-recognized as a potential microalgal source of valuable compounds such as polyunsaturated fatty acids, particularly, eicosapentaenoic acid (EPA). The content and profile of these lipids is highly dependent on the growth conditions and can, therefore, be tailored through modulation of the growth parameters, specifically, temperature. Moreover, biological activities are composition dependent. In the present work, lipid extracts obtained from N. oculata, grown under constant temperature and under modulated temperature stress (to increase EPA content; Str) were characterized by GC-FID and several bioactivities were evaluated, namely, antioxidant (L-ORACFL), cytotoxic (MTT), adipolytic, anti-hepatic lipid accumulation (steatosis), and anti-inflammatory properties. Both extracts exhibited antioxidant activity (c.a. 49 µmol Troloxequivalent/mgextract) and the absence of toxicity (up to 800 µg/mL) toward colon and hepatic cells, adipocytes, and macrophages. They also induced adipolysis and the inhibition of triglycerides hepatic accumulation, with a higher impact from Str. In addition, anti-inflammatory activity was observed in the lipopolysaccharide-induced inflammation of macrophages in the presence of either extract, since lower levels of pro-inflammatory interleukin-6 and interferon-ß were obtained, specifically by Str. The results presented herein revealed that modulated temperature stress may enhance the health effects of N. oculata lipid extracts, which may be safely utilized to formulate novel food products.
Asunto(s)
Microalgas , Estramenopilos , Triglicéridos , Ácido Eicosapentaenoico , Ácidos Grasos Insaturados , TemperaturaRESUMEN
Animal breeding programs have used molecular genetic tools as an auxiliary method to identify and select animals with superior genetic merit for milk production and milk quality traits as well as disease resistance. Genes of the major histocompatibility complex (MHC) are important molecular markers for disease resistance that could be applied for genetic selection. The aim of this study was to identify single nucleotide polymorphisms (SNPs) and haplotypes in DRB2, DRB3, DMA, and DMB genes in Murrah breed and to analyze the association between molecular markers and milk, fat, protein and mozzarella production, fat and protein percentage, and somatic cell count. Two hundred DNA samples from Murrah buffaloes were used. The target regions of candidate genes were amplified by polymerase chain reaction (PCR) followed by sequencing and identification of polymorphisms. Allele and genotype frequencies, as well as linkage disequilibrium between SNPs, were calculated. Genotypes were used in association analyses with milk production and quality traits. Except for the DMA gene, identified as monomorphic, the other genes presented several polymorphisms. The DMB, DRB2, and DRB3 genes presented two, six, and seven SNPs, respectively. Fifty-seven haplotype blocks were constructed from 15 SNPs identified, which was used in association analyses. All the studied traits had at least one associated haplotype. In conclusion, it is suggested that the haplotypes found herein can be associated with important traits related to milk production and quality.
Asunto(s)
Búfalos/genética , Haplotipos , Complejo Mayor de Histocompatibilidad/genética , Leche/química , Polimorfismo de Nucleótido Simple , Animales , Búfalos/metabolismo , FemeninoRESUMEN
Seaweeds, which have been widely used for human consumption, are considered a potential source of biological compounds, where enzyme-assisted extraction can be an efficient method to obtain multifunctional extracts. Chemical characterization of Sargassum muticum and Osmundea pinnatifida extracts obtained by Alcalase and Viscozyme assisted extraction, respectively, showed an increment of macro/micro elements in comparison to the corresponding dry seaweeds, while the ratio of Na/K decreased in both extracts. Galactose, mannose, xylose, fucose, and glucuronic acid were the main monosaccharides (3.2-27.3 mg/glyophilized extract) present in variable molar ratios, whereas low free amino acids content and diversity (1.4-2.7 g/100gprotein) characterized both extracts. FTIR-ATR and 1H NMR spectra confirmed the presence of important polysaccharide structures in the extracts, namely fucoidans from S. muticum or agarans as sulfated polysaccharides from O. pinnatifida. No cytotoxicity against normal mammalian cells was observed from 0 to 4 mglyophilized extract/mL for both extracts. The comprehensive characterization of the composition and safety of these two extracts fulfils an important step towards their authorized application for nutritional and/or nutraceutical purposes.
Asunto(s)
Suplementos Dietéticos , Extractos Vegetales/química , Rhodophyta/química , Sargassum/química , Algas Marinas/química , Animales , Línea Celular , Fibroblastos , Ratones , Estructura Molecular , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Polisacáridos/toxicidad , Espectroscopía de Protones por Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier , Subtilisinas/metabolismo , Pruebas de ToxicidadRESUMEN
Functional screening of metagenomic libraries is an important tool for the discovery of new molecules. The metabolic diversity of microorganisms enables survival in harsh environments and is related to the production of enzymes. In this study, we identified a protease-producing clone from a metagenomic library derived from mangrove sediment. The protease was purified by ammonium sulphate precipitation and gel filtration chromatography, with a yield of 77.27% and a specific activity of 8.57 U µg-1 . It had a molecular weight of approximately 70 kDa. MS/MS in ESI-Q-TOF revealed nine peptides similar to a peptidase of Bacillus safensis. The aligned partial sequence showed 47.48% identity and 82.74% similarity to the conserved domains of a glutamyl aminopeptidase from the human gut metagenome and 32.12% total coverage. The protease had an optimal pH of 8.5 and optimal activity at 60°C. At pH 9-12, its activity was greater than 80%. It had moderate thermotolerance and thermostability at temperatures of 40 and 50 °C. The KM and Vmax values were estimated to be 0.92 mg ml-1 , and 13.15 mmol min-1 for azocasein. Substrate specificity analysis showed that PR4A3 was active on gelatin, blood, egg yolk, and milk. These results support the potential use of PR4A3 in biotechnological applications.
Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Endopeptidasas/química , Endopeptidasas/metabolismo , Sedimentos Geológicos/microbiología , Metagenómica , Humedales , Secuencia de Aminoácidos , Bacillus/enzimología , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Biotecnología , Brasil , Cromatografía en Gel , Endopeptidasas/genética , Endopeptidasas/aislamiento & purificación , Activación Enzimática , Pruebas de Enzimas , Estabilidad de Enzimas , Calor , Concentración de Iones de Hidrógeno , Cinética , Metagenoma , Peso Molecular , Péptido Hidrolasas/química , Péptido Hidrolasas/genética , Péptido Hidrolasas/aislamiento & purificación , Sales (Química) , Alineación de Secuencia , Especificidad por Sustrato , Espectrometría de Masas en Tándem , TemperaturaRESUMEN
In recent years, emerging contaminants (e.g. pesticides and their metabolites, pharmaceuticals, personal and house care products, life-style compounds, food additives, industrial products and wastes, as well as nanomaterials) have become a problem to the environment. In fact, the cumulative use of a panoply of chemical substances in agriculture, industrial activities, in our homes and in health care services has led to their recent appearance in detectable levels in soils, surface, and groundwater resources, with unpredictable consequences for these ecosystems. Few data exist regarding the toxicity and potential for bioaccumulation in biota. When available, data were obtained only for some representatives of the main groups of chemical substances, and for a limited number of species, following non-standard protocols. This makes difficult the calculation of predicted no effect concentrations (PNEC) and the existence of sufficient data to set limits for their release into the environment. This is particularly concerning for the soil compartment, since only recently the scientific community, regulators, and the public have realised the importance of protecting this natural resource and its services to guarantee the sustainability of terrestrial ecosystems and human well-being. In this context, this review paper aims to identify the major groups of soil emerging contaminants, their sources, pathways and receptors, and in parallel to analyse existing ecotoxicological data for soil biota.
Asunto(s)
Biota/efectos de los fármacos , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/toxicidad , Suelo/química , Ecosistema , Ecotoxicología , Humanos , Microbiología del Suelo/normasRESUMEN
As part of a tier 3 risk assessment performed for a uranium mining area, the ability of soils with different degrees of metal contamination to degrade organic matter was assessed using litter bags filled with leaves of Quercus robur, Pinus pinaster, Salix atrocinerea, or a mixture of the three species. Litter bags were exposed at different sites within the mine area and at a reference area for 3, 6, 9, and 12 months. Biomass loss, nitrogen (N), phosphorus (P), carbon (C) and total fatty acid, total phenolic, and ergosterol contents were assessed for each litter bag retrieved from the field. The decomposition of litter at each site seemed to be governed by a complex interaction of many different factors. After 12 months of exposure, leaves from the most contaminated sites were distinguishable from those from the reference site. In the reference site, the greatest percentages of biomass loss were attained by Q. robur and P. pinaster leaves. These species displayed the second highest and the lowest C-to-N ratios, respectively. In addition, the high P content of the litter from these two species may have favored microbial colonization. The results suggest that the decomposition of P. pinaster and Q. robur leaves may have been favored at the reference site by the high abundance of both species at this site and the subsequent adaptation of the microbial community to their litter. Our study shows that different species of leaf litter should be used to discriminate between contaminated sites with different levels of contamination.
Asunto(s)
Minería , Microbiología del Suelo , Contaminantes Radiactivos del Suelo/toxicidad , Uranio/toxicidad , Carbono/análisis , Ecosistema , Nitrógeno/análisis , Fósforo/análisis , Suelo/químicaRESUMEN
This study attempts a treatment strategy of a bleached kraft pulp mill effluent with Rhizopus oryzae or Pleurotus sajor caju encapsulated on silica-alginate (biocomposite of silica-alginate-fungi, with the purpose of reducing its potential impact in the environment. Active (alive) or inactive (death by sterilization) Rhizopus oryzae or Pleurotus sajor caju was encapsulated in alginate beads. Five beads containing active and inactive fungus were placed in a mold and filled with silica hydrogel (biocomposites). The biocomposites were added to batch reactors containing the bleached kraft pulp mill effluent. The treatment of bleached kraft pulp mill effluent by active and inactive biocomposites was performed throughout 29 days at 28°C. The efficiency of treatment was evaluated by measuring the removal of organic compounds, chemical oxygen demand and the relative absorbance ratio over time. Both fungi species showed potential for removal of organic compounds, colour and chemical oxygen demand. Maximum values of reduction in terms of colour (56%), chemical oxygen demand (65%) and organic compounds (72-79%) were attained after 29 days of treatment of bleached kraft pulp mill effluent by active Rhizopus oryzae biocomposites. The immobilization of fungi, the need for low fungal biomass, and the possibility of reutlization of the biocomposites clearly demonstrate the industrial and environmental interest in bleached kraft pulp mill effluent treatment by silica-alginate-fungi biocomposites.
Asunto(s)
Reactores Biológicos/microbiología , Compuestos Orgánicos/metabolismo , Pleurotus/metabolismo , Rhizopus/metabolismo , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/metabolismo , Alginatos/química , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Cromatografía de Gases y Espectrometría de Masas , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Residuos Industriales , Dióxido de Silicio/química , Extracción en Fase Sólida , Espectrofotometría , Factores de TiempoRESUMEN
Alternative vectors to deliver viable cells of probiotics, to those conferring limited resistance to gastrointestinal conditions, still need to be sought. Therefore the main goal of the study was to develop tablets able to protect entrapped probiotic bacteria from gastric acidity, thus providing an easily manufacturing scale-up dosage form to deliver probiotics to the vicinity of the human colon. Whey protein concentrate microparticles with Lactobacillus paracasei L26 were produced by spray-drying and incorporated in tablets with cellulose acetate phthalate and sodium croscarmellose. The viability of L. paracasei L.26 throughout tableting as well as its gastric resistance and release from the tablets were evaluated. Storage stability of L. paracasei L26 tablets was also performed by evaluation of viable cells throughout 60 days at 23°C and 33% relative humidity. A decrease of approximately one logarithmic cycle was observed after the acid stage and the release of L. paracasei L26 from the tablets occurred only after 4 h in the conditions tested. Microencapsulated L. paracasei L26 in tablets revealed some susceptibility to the storage conditions tested since the number of viable cells decreased 2 log cycles after 60 days of storage. However, the viability of L. paracasei L26 after 45 days of storage did not reveal significant susceptibility upon exposure to simulated gastrointestinal conditions. The developed probiotic tablets revealed to be potential vectors for delivering viable cells of L. paracasei L26 and probably other probiotics to persons/patients who might benefit from probiotic therapy.
Asunto(s)
Lactobacillus , Probióticos , ComprimidosRESUMEN
The olive oil mill wastewater (OMW) is a problematic and polluting effluent which may degrade the soil and water quality, with critical negative impacts on ecosystems functions and services provided. The main purpose of this review paper is presenting the state of the art of OMW treatments focusing on their efficiency to reduce OMW toxicity, and emphasizing the role of ecotoxicological tests on the evaluation of such efficiency before the up-scale of treatment methodologies being considered. In the majority of research works, the reduction of OMW toxicity is related to the degradation of phenolic compounds (considered as the main responsible for the toxic effects of OMW on seed germination, on bacteria, and on different species of soil and aquatic invertebrates) or the decrease of chemical oxygen demand content, which is not scientifically sound. Batteries of ecotoxicological tests are not applied before and after OMW treatments as they should be, thus leading to knowledge gaps in terms of accurate and real assessment of OMW toxicity. Although the toxicity of OMW is usually high, the evaluation of effects on sub-lethal endpoints, on individual and multispecies test systems, are currently lacking, and the real impacts yielded by its dilution, in freshwater trophic chains of receiving systems can not be assessed. As far as the terrestrial compartment is considered, ecotoxicological data available include tests only with plants and the evaluation of soil microbial parameters, reflecting concerns with the impacts on crops when using OMW for irrigation purposes. The evaluation of its ecotoxicity to other edaphic species were not performed giving rise to a completely lack of knowledge about the consequences of such practice on other soil functions. OMW production is a great environmental problem in Mediterranean countries; hence, engineers, chemists and ecotoxicologists should face this problem together to find an ecologically friend solution.
Asunto(s)
Ecosistema , Residuos Industriales/efectos adversos , Aceites de Plantas/toxicidad , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/toxicidad , Biodegradación Ambiental , Monitoreo del Ambiente/métodos , Humanos , Residuos Industriales/análisis , Exposición Profesional/efectos adversos , Aceite de Oliva , Aceites de Plantas/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Included in the 2nd tier of a site specific risk assessment that is being carried out in an abandoned uranium mine (Cunha Baixa uranium mine, Central Portugal), fatty acids biomarkers and sterols were analyzed to assess the impact of soil contamination with metals and radionuclides in the structure of the microbial community in seven sampling sites located at different distances from the mine. Surface soil samples were collected in those sampling sites in the four different seasons of the year. Principal component analysis (PCA) was performed on fatty acid biomarkers and sterols. Subsequently PCA scores obtained for both components were used to test the effect of sites and seasons, on soil samples collected in the Cunha Baixa uranium mine, through bi-factorial ANOVAs. Through PCA analysis, two distinct groups were set apart along the first two components. One group included sites at a great distance from the mine which were negatively correlated with higher contents of iC15:0 and iC17:0, both indicators of Gram-positive bacteria, as well as with ergosterol, cholestanol and cholesterol. The second group, in turn, was composed of the sampling sites most impacted by ore exploration, in situ leaching of poor ore, and spread of sludge from the effluent treatment pond. These sites were positively correlated with higher levels of iC16:0 (Gram-positive bacteria indicator), cyC17:0 (generally common in gram negative bacteria) and C18:0 and C17:0 biomarkers of non-specific bacteria. The profile of fatty acids obtained in the sampling sites revealed variable predominance of groups of bacteria which are a clear indication of differences in the soil microbial communities that are directly related to the environmental conditions prevailing in the uranium mine area.
Asunto(s)
Ácidos Grasos/análisis , Metales/toxicidad , Consorcios Microbianos/efectos de los fármacos , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Esteroles/análisis , Análisis de Varianza , Bacterias/efectos de los fármacos , Biomarcadores/análisis , Monitoreo del Ambiente , Hongos/efectos de los fármacos , Minería , Análisis de Componente Principal , Medición de Riesgo/métodos , Contaminantes del Suelo/análisis , UranioRESUMEN
Sepsis-induced myocardial dysfunction considerably increases mortality risk in patients with sepsis. Previous studies from our group have shown that sepsis alters the expression of structural proteins in cardiac cells, resulting in cardiomyocyte degeneration and impaired communication between cardiac cells. Caveolin-3 (CAV3) is a structural protein present in caveolae, located in the membrane of cardiac muscle cells, which regulates physiological processes such as calcium homeostasis. In sepsis, there is a disruption of calcium homeostasis, which increases the concentration of intracellular calcium, which can lead to the activation of potent cellular enzymes/proteases which cause severe cellular injury and death. The purpose of the present study was to test the hypotheses that sepsis induces CAV3 overexpression in the heart, and the regulation of L-type calcium channels directly relates to the regulation of CAV3 expression. Severe sepsis increases the expression of CAV3 in the heart, as immunostaining in our study showed CAV3 presence in the cardiomyocyte membrane and cytoplasm, in comparison with our control groups (without sepsis) that showed CAV3 presence predominantly in the plasma membrane. The administration of verapamil, an L-type calcium channel inhibitor, resulted in a decrease in mortality rates of septic mice. This effect was accompanied by a reduction in the expression of CAV3 and attenuation of cardiac lesions in septic mice treated with verapamil. Our results indicate that CAV3 has a vital role in cardiac dysfunction development in sepsis and that the regulation of L-type calcium channels may be related to its expression.
Asunto(s)
Caveolina 3/metabolismo , Corazón/efectos de los fármacos , Sepsis/tratamiento farmacológico , Verapamilo/uso terapéutico , Animales , Canales de Calcio Tipo L , Humanos , Masculino , Ratones , Sepsis/mortalidad , Sepsis/patología , Análisis de Supervivencia , Verapamilo/farmacologíaRESUMEN
NPCdc is a synthetic natriuretic peptide that was originally derived from another peptide, the NP2_Casca, isolated from Crotalus durissus cascavella venom. These molecules share 70% structural homology with natriuretic peptides obtained from different species, including humans. NP2_Casca induces vasorelaxation and increases nitric oxide levels independently of natriuretic peptide receptors A and B. This study aimed to investigate whether NPCdc-induced hypotension in control rats and rats with a reduced kidney mass is associated with effects on the glomerular filtration rate, NADPH oxidase activity and components downstream of natriuretic peptide receptor C (NPR-C). Anaesthetized Wistar rats that were subjected to a sham operation and 5/6 nephrectomy (5/6Nx) were infused with saline (vehicle) or NPCdc (7.5⯵g/kg/min) for 70â¯min. The NPCdc treatment decreased the mean arterial pressure and NADPH oxidase activity while simultaneously increasing the glomerular filtration rate, fractional Na+ excretion and nitric oxide level. After 70â¯min, the levels of p-AKT Ser-473, p-eNOS Ser-1177, p-nNOS Ser-1417 and p-iNOSTyr-151 were not affected. However, p-ERK1/2 Thr-202/Tyr-204 levels were altered. Thus, nitric oxide and components of NPR-C signalling mediate the effects of NPCdc. The results suggest a potential therapeutic application of this peptide for cardiorenal syndrome.
Asunto(s)
Aorta/efectos de los fármacos , Riñón/efectos de los fármacos , Péptido Natriurético Tipo-C/farmacología , Nefrectomía , Óxido Nítrico/metabolismo , Animales , Aorta/citología , Aorta/metabolismo , Aorta/fisiología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Frecuencia Cardíaca/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Riñón/citología , Riñón/metabolismo , Riñón/fisiología , Masculino , NADPH Oxidasas/metabolismo , Péptido Natriurético Tipo-C/síntesis química , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/metabolismoRESUMEN
The aim of this study is to identify the influence of social dimensions of the work environment and the employees' felt responsibility on the transfer of safety training. We tested a model in which responses and reactions from safety players such as coworkers, supervisors, and safety professionals are positively related to the transfer of training (TT), through the mediating effect of the employees' felt responsibility and the moderating influence of supervisor support and sanctions. A two-time data collection was implemented among blue-collar employees, all low qualified, from four city councils who attended a fundamental safety training program delivered by in-house safety trainers, all safety professionals (n = 203). Data analysis revealed that (a) supervisors' safety responses, coworkers' safety responses, and safety professionals' reactions positively influenced the TT, an effect (b) mediated by employees' felt responsibility and (c) moderated by supervisor sanctions, but not by supervisor support. The results suggest that high sanctions enhance the positive effect of high self-responsibility on TT, and, importantly, aggravate the negative effect of low self-responsibility on TT. This is the first study to empirically test both the influence of felt responsibility and the safety professionals' reactions in the transfer process. Research should continue to examine the former construct's influence on the transfer process including, for example, its effect on supervisor support, and the latter as a safety-related social dimension variable of the work environment. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Asunto(s)
Empleados de Gobierno/psicología , Relaciones Interprofesionales , Cultura Organizacional , Administración de la Seguridad , Apoyo Social , Lugar de Trabajo/psicología , Adulto , Análisis Factorial , Femenino , Humanos , Gobierno Local , Masculino , Persona de Mediana Edad , Salud Laboral , Administración de la Seguridad/organización & administración , Encuestas y Cuestionarios , Transferencia de Experiencia en PsicologíaRESUMEN
The synthetic peptide PnPP-19 comprehends 19 amino acid residues and it represents part of the primary structure of the toxin δ-CNTX-Pn1c (PnTx2-6), isolated from the venom of the spider Phoneutria nigriventer. Behavioural tests suggest that PnPP-19 induces antinociception by activation of CB1, µ and δ opioid receptors. Since the peripheral and central antinociception induced by PnPP-19 involves opioid activation, the aim of this work was to identify whether this synthetic peptide could directly activate opioid receptors and investigate the subtype selectivity for µ-, δ- and/or κ-opioid receptors. Furthermore, we also studied the modulation of calcium influx driven by PnPP-19 in dorsal root ganglion neurons, and analyzed whether this modulation was opioid-mediated. PnPP-19 selectively activates µ-opioid receptors inducing indirectly inhibition of calcium channels and hereby impairing calcium influx in dorsal root ganglion (DRG) neurons. Interestingly, notwithstanding the activation of opioid receptors, PnPP-19 does not induce ß-arrestin2 recruitment. PnPP-19 is the first spider toxin derivative that, among opioid receptors, selectively activates µ-opioid receptors. The lack of ß-arrestin2 recruitment highlights its potential for the design of new improved opioid agonists.
Asunto(s)
Canales de Calcio/fisiología , Péptidos/farmacología , Receptores Opioides mu/fisiología , Venenos de Araña/farmacología , Animales , Ganglios Espinales/fisiología , Células HEK293 , Humanos , Neuronas/fisiología , Oocitos/efectos de los fármacos , Oocitos/fisiología , Ratas Wistar , Xenopus laevisRESUMEN
Plastic yearly production has surpassed the 300milliontons mark and recycling has all but failed in constituting a viable solution for the disposal of plastic waste. As these materials continue to accumulate in the environment, namely, in rivers and oceans, in the form of macro-, meso-, micro- and nanoplastics, it becomes of the utmost urgency to find new ways to curtail this environmental threat. Multiple efforts have been made to identify and isolate microorganisms capable of utilizing synthetic polymers and recent results point towards the viability of a solution for this problem based on the biodegradation of plastics resorting to selected microbial strains. Herein, the response of the fungus Zalerion maritimum to different times of exposition to polyethylene (PE) pellets, in a minimum growth medium, was evaluated, based on the quantified mass differences in both the fungus and the microplastic pellets used. Additionally, molecular changes were assessed through attenuated total reflectance Fourier transform Infrared Spectroscopy (FTIR-ATR) and Nuclear Magnetic Resonance (NMR). Results showed that, under the tested conditions, Z. maritimum is capable of utilizing PE, resulting in the decrease, in both mass and size, of the pellets. These results indicate that this naturally occurring fungus may actively contribute to the biodegradation of microplastics, requiring minimum nutrients.
Asunto(s)
Ascomicetos/metabolismo , Plásticos/química , Polietileno/química , Monitoreo del Ambiente , Océanos y MaresRESUMEN
Edible mushrooms including Pholiota nameko are excellent sources of extractable bioactive compounds with much to explore. Enzymatic extractions with Cellulase and Viscozyme were responsible for highest extraction yields (67-77%). No strong antioxidant activity was observed although extracts were able to scavenge ABTS(+) and OH(+). Potential prebiotic activity was observed in all extracts, some increasing 1.4-2 Log cycles of Lactobacillus acidophilus La-5 and Bifidobacterium animalis BB12. 30-50% α-glucosidase inhibition was observed in ultrasound, Flavourzyme and Cellulase extracts. Flavourzyme and Cellulase extracts are richer in macro (Mg, K and P) and micro elements (Zn, Mn and Fe) in comparison to mushroom. Monosaccharides content and profile varied slightly among both extracts with predominance of glucose, galactose and mannose with no uronic acids detection; Flavourzyme extract reported higher free amino acids content. Presence of α and ß-glycosidic structures such as glucans and glucan-protein complexes are among the polysaccharides found in both extracts.
Asunto(s)
Pholiota/química , Celulasa/metabolismo , Glucanos/análisis , Inhibidores de Glicósido Hidrolasas/farmacología , Espectroscopía de Resonancia Magnética , Monosacáridos/análisis , Polisacáridos/análisisRESUMEN
Six representative edible seaweeds from the Central West Portuguese Coast, including the less studied Osmundea pinnatifida, were harvested from Buarcos bay, Portugal and their chemical characterization determined. Protein content, total sugar and fat contents ranged between 14.4% and 23.8%, 32.4% and 49.3% and 0.6-3.6%. Highest total phenolic content was observed in Codium tomentosum followed by Sargassum muticum and O. pinnatifida. Fatty acid (FA) composition covered the branched chain C13ai to C22:5 n3 with variable content in n6 and n3 FA; low n6:n3 ratios were observed in O. pinnatifida, Grateloupia turuturu and C. tomentosum. Some seaweed species may be seen as good sources of Ca, K, Mg and Fe, corroborating their good nutritional value. According to FTIR-ATR spectra, G. turuturu was associated with carrageenan seaweed producers whereas Gracilaria gracilis and O. pinnatifida were mostly agar producers. In the brown algae, S. muticum and Saccorhiza polyschides, alginates and fucoidans were the main polysaccharides found.
Asunto(s)
Chlorophyta/química , Phaeophyceae/química , Rhodophyta/química , Algas Marinas/química , Bahías , PortugalRESUMEN
Silica monoliths have been used for more than half a century in a wide variety of applications, such as stationary phases for microextraction fibers, capillary columns for chromatography, in the encapsulation of biomolecules for affinity chromatography and for microfluidic or microarray chips and, more recently, and less well known for wastewater treatment. The main objective of this review article is to specifically overview the strategies that use silica monoliths for the removal of chemical pollutants from wastewater effluents or prepared solutions. The discussion of advantages and drawbacks of such strategies will be supported with the main studies carried out so far which have been performed in laboratory environment only. The application and potential research interest in several strategies using composites and biocomposites based silica monoliths as cleaning systems are also discussed.