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1.
Materials (Basel) ; 16(17)2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37687736

RESUMO

Bioconsolidation treatment using bacterial carbonatogenesis has been proposed as an environmentally friendly strategy for the efficient preservation of damaged stones, particularly suitable for carbonate stones. The study presented here deals with the evaluation of the performance of this treatment, applied to damaged carbonate stones in two historical buildings in Spain. The methodology applied in this research serves as a reference for future similar studies. Results showed significant improvement in the petrophysical and mechanical properties of the damaged stone following the treatment through the production of calcite and vaterite by the abundant carbonatogenic bacteria inhabiting the stone. These bacteria were able to effectively consolidate weathered areas if an adequate nutritional solution was employed, thereby augmenting the stone's resistance, as evidenced by the Drilling Resistance Measurement System (DRMS). FESEM images showed calcified bacteria and calcified exopolymeric substances (EPS) consolidating stone minerals without blocking their pores. In addition to consolidation, this biotreatment improves the stone's behavior against water absorption and increases the contact angle of water droplets without significant modifications in the pore size or diminishing vapor permeability. No color changes are observed. Overall, these results show that the application of the nutritional solution (M-3P) for in situ consolidation of different types of porous carbonate building stones is a highly effective conservation method, with no modification of the chemical composition of the treated materials.

2.
Environ Pollut ; 319: 120994, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603757

RESUMO

Microplastics (MPs) are present across the global ocean and can be encountered by many species, including zooplankton. Although they fall within the size range of zooplankton prey, there are few studies on MPs ingestion carried out in situ. In this study, we analyzed MPs ingestion during two seasons (rainy and dry) of organisms from 5 taxonomic groups of zooplankton from two bays of the Mexican central Pacific: Manzanillo and Navidad. In total, 2643 individuals were analyzed, and of those 23 individuals contained MPs. The ingestion rate by taxonomic group was 1 MP/36 copepods (0.02), 1 MP/30 decapods-mysis (0.03), 1 MP/29 decapods-megalopa (0.03), and 1 MP/200 fish larvae (0.005). No plastics were found in chaetognaths, amphipods, or decapods-zoea. The average length of the ingested particles was 468.1 ± 113.8 µm, with a minimum of 15.6 and a maximum of 647.6 µm. All MPs >300 µm were fibers, with diameters <50 µm. Fragments were the most abundant MPs (54.2%), followed by fibers (34.2%) and spheres (11.4%). Statistical analyses showed no significant differences (p > 0.05) between the bays or seasons. Using RAMAN spectroscopy, it was possible to identify 6 different types of polymers, with poly (ethylene:propylene) being the most abundant (42.8%). This polymer is commonly used to manufacture plastic bags, ropes and fishing nets. The results confirm that certain zooplankton groups are consuming MPs and suggest that omnivorous species are more likely to ingest MPs, possibly due to their capacity for foraging flexibility and opportunistic feeding strategies. However, the ingestion of MPs cannot be attributed to a single factor; it is necessary to consider variables such as the sampling area, feeding strategy, size, and seasonality to understand the dynamics of MPs ingestion by zooplankton groups.


Assuntos
Poluentes Químicos da Água , Zooplâncton , Animais , Microplásticos , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Polietileno , Ingestão de Alimentos
3.
Nutrients ; 14(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36501132

RESUMO

The consumption of energy drinks (EDs) is increasing globally while the evidence and concern about the potential health risks are also growing. Caffeine (generally 32 mg/100 mL) together with a wide variety of other active components such as taurine (usually 4000 mg/L) and D-glucuronolactone (generally 2400 mg/L) are the main ingredients of EDs. This study aims to assess the exposures to caffeine, taurine and D-glucuronolactone from EDs in various consumption scenarios and consumer profiles and to characterize the risks by evaluating caffeine and taurine intakes with their reference values and by calculating the margin of safety (MOS) for D-glucuronolactone. While the exposure assessment results showed that caffeine intakes from EDs ranged from 80 to 160 mg (1.14-4 mg/kg b.w.) for the considered scenarios, the risk characterization estimated some risks that could be managed with consumption recommendations such as limiting EDs in 40, 60 and 80 kg b.w. consumers to 175, 262.5 and 350 mL, respectively, to prevent sleep disturbances and to 375, 562.5 and 750 mL to prevent general caffeine adverse health risks, respectively. Dietary exposure to D-glucuronolactone from EDs ranged from 600 to 1200 mg (7.5-30 mg/kg b.w.). As D-glucuronolactone MOS ≥ 100 is only observed when EDs consumption is limited to 250 mL, for individuals weighing above 60 kg, some risks were observed in some of the studied scenarios. A taurine exposure from EDs varied from 1000 to 2000 mg (12.5-50 mg/kg b.w.) and consumptions over 500 mL were estimated to generate intakes above the reference value. In conclusion, the management of these risks requires a European legal framework for EDs with maximum limits for the active components, volume size limitations and labeling improvements along with the development of education and awareness programs and risk communication actions in collaboration with the industry and society.


Assuntos
Bebidas Energéticas , Humanos , Bebidas Energéticas/efeitos adversos , Cafeína/efeitos adversos , Taurina/efeitos adversos , Medição de Risco
4.
Adv Nutr ; 12(4): 1514-1539, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33578416

RESUMO

High meat consumption has been associated with increased oxidative stress mainly due to the generation of oxidized compounds in the body, such as malondialdehyde, 4-hydroxy-nonenal, oxysterols, or protein carbonyls, which can induce oxidative damage. Meat products are excellent matrices for introducing different bioactive compounds, to obtain functional meat products aimed at minimizing the pro-oxidant effects associated with high meat consumption. Therefore, this review aims to summarize the concept and preparation of healthy and functional meat, which could benefit antioxidant status. Likewise, the key strategies regarding meat production and storage as well as ingredients used (e.g., minerals, polyphenols, fatty acids, walnuts) for developing these functional meats are detailed. Although most effort has been made to reduce the oxidation status of meat, newly emerging approaches also aim to improve the oxidation status of consumers of meat products. Thus, we will delve into the relation between functional meats and their health effects on consumers. In this review, animal trials and intervention studies are discussed, ascertaining the extent of functional meat products' properties (e.g., neutralizing reactive oxygen species formation and increasing the antioxidant response). The effects of functional meat products in the frame of diet-gene interactions are analyzed to 1) discover target subjects that would benefit from their consumption, and 2) understand the molecular mechanisms that ensure precision in the prevention and treatment of diseases, where high oxidative stress takes place. Long-term intervention-controlled studies, testing different types and amounts of functional meat, are also necessary to ascertain their positive impact on degenerative diseases.


Assuntos
Produtos da Carne , Animais , Antioxidantes/farmacologia , Humanos , Malondialdeído , Carne/análise , Estresse Oxidativo
5.
Arch Biochem Biophys ; 697: 108680, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33220265

RESUMO

The study of calmodulin (CaM) functions in living cells has been tackled up to date using cell-permeant CaM inhibitors or interference-RNA methods. CaM inhibitors may lack specificity and the siRNA interference approach is challenging, as all three CaM genes expressing an identical protein in mammals have to be blocked. Therefore, we recently introduced a novel genetic system using CRISPR/Cas9-mediated gene deletion and conditional CaM expression to study the function of CaM in HeLa cells. Here, we describe the effect of CaM downregulation on the basal and epidermal growth factor (EGF)-dependent 2D- and 3D-migration in HeLa cells. CaM downregulation inhibited cell migration on a 2D-surface in the absence but not in the presence of EGF. In contrast, CaM downregulation led to inhibition of 3D-migration across a porous membrane both in the absence and presence of EGF. CaM downregulation decreased the expression of Rac1, Cdc42 and RhoA, all known to play crucial roles in cell migration. These results show that EGF-dependent 2D- and 3D-migration utilize distinct CaM-regulated systems and identify several essential migratory proteins directly or indirectly regulated by CaM.


Assuntos
Calmodulina/deficiência , Calmodulina/genética , Movimento Celular/genética , Regulação para Baixo , Técnicas de Inativação de Genes , Fator de Crescimento Epidérmico/metabolismo , Células HeLa , Humanos , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
6.
J Cell Physiol ; 236(7): 4997-5011, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33305427

RESUMO

The epidermal growth factor receptor (EGFR) harbors a calmodulin (CaM)-binding domain (CaM-BD) and a CaM-like domain (CaM-LD) upstream and downstream, respectively, of the tyrosine kinase (TK) domain. We demonstrate in this paper that deletion of the positively charged CaM-BD (EGFR/CaM-BD∆) inactivated the TK activity of the receptor. Moreover, deletion of the negatively charged CaM-LD (EGFR/CaM-LD∆), leaving a single negative residue (glutamate), reduced the activity of the receptor. In contrast, substituting the CaM-LD with a histidine/valine-rich peptide (EGFR/InvCaM-LD) caused full inactivation. We also demonstrated using confocal microscopy and flow cytometry that the chimera EGFR-green fluorescent protein (GFP)/CaM-BD∆, the EGFR/CaM-LD∆, and EGFR/InvCaM-LD mutants all bind tetramethylrhodamine-labelled EGF. These EGFR mutants were localized at the plasma membrane as the wild-type receptor does. However, only the EGFR/CaM-LD∆ and EGFR/InvCaM-LD mutants appear to undergo ligand-dependent internalization, while the EGFR-GFP/CaM-BD∆ mutant seems to be deficient in this regard. The obtained results and in silico modelling studies of the asymmetric structure of the EGFR kinase dimer support a role of a CaM-BD/CaM-LD electrostatic interaction in the allosteric activation of the EGFR TK.


Assuntos
Calmodulina/metabolismo , Membrana Celular/metabolismo , Animais , Células CHO , Sinalização do Cálcio/fisiologia , Linhagem Celular , Cricetulus , Ativação Enzimática/fisiologia , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Ligação Proteica/fisiologia , Domínios Proteicos/fisiologia , Proteínas Tirosina Quinases/metabolismo
7.
Front Microbiol ; 11: 599144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240254

RESUMO

To overcome the limitations of traditional conservation treatments used for protection and consolidation of stone and lime mortars and plasters, mostly based on polymers or alkoxysilanes, a novel treatment based on the activation of indigenous carbonatogenic bacteria has been recently proposed and applied both in the laboratory and in situ. Despite very positive results, little is known regarding its effect on the evolution of the indigenous bacterial communities, specially under hot and humid tropical conditions where proliferation of microorganisms is favored, as it is the case of the Maya area. Here, we studied changes in bacterial diversity of severely degraded tuff stone and lime plaster at the archeological Maya site of Copan (Honduras) after treatment with the patented sterile M-3P nutritional solution. High-throughput sequencing by Illumina MiSeq technology shows significant changes in the bacterial population of the treated stones, enhancing the development of Arthrobacter, Micrococcaceae, Nocardioides, Fictibacillus, and Streptomyces, and, in one case, Rubrobacter (carved stone blocks at Structure 18). In the lime plaster, Arthrobacter, Fictibacillus, Bacillus, Agrococcus, and Microbacterium dominated after treatment. Most of these detected genera have been shown to promote calcium carbonate biomineralization, thus implying that the novel bio-conservation treatment would be effective. Remarkably, the treatment induced the reduction or complete disappearance of deleterious acid-producing bacteria such as Marmoricola or the phylum Acidobacteria. The outcome of this study demonstrates that such a bio-conservation treatment can safely and effectively be applied on temples, sculptures and stuccos of the Maya area and, likely, in other hot and humid environments.

8.
Heliyon ; 6(5): e03922, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32420488

RESUMO

The growth factor receptor bound protein 7 (Grb7) is a Ca2+-dependent calmodulin (CaM)-binding adaptor protein implicated, among other functions, in cell proliferation, migration and tumor-associated angiogenesis. The goal of this study was to determine whether a peptide based on the CaM binding site of Grb7 disrupts cellular processes, relevant for the malignancy of tumor cells, in which this adaptor protein is implicated. We designed synthetic myristoylated and non-myristoylated peptides corresponding to the CaM-binding domain of human Grb7 with the sequence 243RKLWKRFFCFLRRS256 and a variant peptide with the mutated sequence RKLERFFCFLRRE (W246E-ΔK247-S256E). The two non-myristoylated peptides bind dansyl-CaM with higher efficiency in the presence than in the absence of Ca2+ and they enter into the cell, as tested with 5(6)-carboxytetramethylrhodamine (TAMRA)-labeled peptides. The myristoylated and non-myristoylated peptides inhibit the proliferation, migration and invasiveness of A431 tumor cells while they enhance their adhesion to the substrate. The myristoylated peptides have stronger inhibitory effect than the non-myristoylated counterparts, in agreement with their expected higher cell-permeant capacity. The myristoylated and non-myristoylated W246E-ΔK247-S256E mutant peptide has a lesser inhibitory effect on cell proliferation as compared to the wild-type peptide. We also demonstrated that the myristoylated peptides were more efficient than the CaM antagonist N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) inhibiting cell migration and equally efficient inhibiting cell proliferation.

9.
J. negat. no posit. results ; 5(2): 202-211, feb. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-194009

RESUMO

Este trabajo describe las virtudes de una investigación centrada en el silicio, uno de los ingredientes más importantes pero menos conocidos de la cerveza, y su acción protectora a nivel neurodegenerativo. Entre los varios factores que contribuyen a la inducción y desarrollo de la enfermedad de Alzheimer, se encuentra el aluminio el cual tiende a concentrarse en el cerebro e inducir, entre otros mecanismos, alteraciones prooxidantes e inflamatorias. El silicio al bloquear esos efectos negativos, se convierte en un ingrediente estrella, que en términos alquimistas sugiere que puede transmutar en oro


This article describes the virtues of a research focused on silicon, one of the most important but least known ingredients in beer, and its protective action at the neurodegenerative level. Among the various factors contributing to the Alzheimer's disease induction and development, aluminum, by concentrating in brain induces, among other mechanisms, pro-oxidant and inflammatory disorders. Silicon, by blocking these negative effects, becomes a star ingredient, which in alchemist terms suggests that has the property to transmute into gold


Assuntos
Humanos , Cerveja/análise , Silício/farmacocinética , Doenças Neurodegenerativas/prevenção & controle , Doença de Alzheimer/prevenção & controle , Fatores de Proteção , Estresse Oxidativo/efeitos dos fármacos , Mediadores da Inflamação/análise , Inflamação/fisiopatologia
10.
Foods ; 9(1)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936523

RESUMO

The autohydrolysis of Lentinus edodes was proposed for the extraction of components with antioxidant properties. Operation under non-isothermal conditions was evaluated and compared with isothermal heating. The influence of process severity was assessed in the range of 0.18 to 4.89 (temperature between 50 and 250 °C), up to 80% (d.b.) The influence of process severity during the autohydrolysis of Lentinus edodes was assessed in the range -0.3 to 4.89 (temperature between 50 and 250 °C). Up to 80% (d.b.) of the initial raw material could be solubilized at 210 °C. The different behavior of the saccharide and phenolic fractions was observed with the treatment temperature. Whereas the highest concentration of the saccharide components (mainly glucooligosaccharides) was found at 210 °C, the maximum phenolic yield was identified at 250 °C. The phenolic content and the antiradical properties of the extract showed a continuous increase with the temperature range studied, and at 250 °C, showed antiradical properties comparable to synthetic antioxidants. Autohydrolysis liquid fractions were used as solvents in the formulation of bioactive starch-based hydrogels, identifying a positive correlation between the gel softening and the extracts' bioactivity features.

11.
J Trace Elem Med Biol ; 57: 60-67, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31563817

RESUMO

BACKGROUND: The main exposure route to methylmercury (MeHg) is from eating fish and shellfish containing this compound. Since 2004, women of childbearing age in Spain have been urged not to eat some species (eg, tuna, shark, and swordfish), instead choosing low-MeHg seafood as part of a healthy diet. OBJECTIVE: To describe maternal total blood mercury (THg) and serum selenium (Se) in a cohort of pregnant women living in Spain as it relates to fish intake during the three trimesters and to assess whether or not Spanish women of childbearing age follow the recommendations listed in fish advisories and choose fish species with lower mercury levels. METHODS: We studied 141 female volunteers of childbearing age (16-45 years), interviewing all participants about their overall eating habits and seafood intake. Hg and Se levels were tested using cold-vapor atomic absorption spectrometry (CVAAS) and electrothermal atomic absorption spectrometry (ETAAS), respectively. RESULTS: Average THg levels in pregnant women were 2.89 µg/L (standard deviation [SD], 2.75 µg/L, geometric mean [GM], 2.19 µg/L), and THg GM was positively associated with fish intake. Mean Se levels in pregnant women were 73.06 µg/L (SD, 13.38 µg/L), and Se levels were found to increase with tuna intake. In 16 (12%) pregnant women, THg was higher than the level recommended by the U.S. Environmental Protection Agency (EPA) (6.4 µg/L). A positive association was also found between THg and serum Se. CONCLUSION: Women of childbearing age in Spain had higher THg levels than women in other Western studies. Our study observed that 12% of women had THg levels above the safety limit set by the EPA (6.4 µg/L), and 31% had levels above the relevant benchmark level of 3.5 µg/L suggested by various researchers.


Assuntos
Mercúrio/sangue , Selênio/sangue , Adolescente , Adulto , Feminino , Humanos , Compostos de Metilmercúrio/sangue , Pessoa de Meia-Idade , Gravidez , Espanha , Adulto Jovem
12.
Sci Total Environ ; 712: 135660, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31791772

RESUMO

The role of microbial processes in bioaccumulation of major and trace elements has been broadly demonstrated. However, microbial communities from marine sediments have been poorly investigated to this regard. In marine environments, particularly under high anthropogenic pressure, heavy metal accumulation increases constantly, which may lead to significant environmental issues. A better knowledge of bacterial diversity and its capability to bioaccumulate metals is essential to face environmental quality assessment. The oligotrophic westernmost Mediterranean, which is highly sensitive to environmental changes and subjected to increasing anthropogenic pressure, was selected for this study. A sediment core spanning the last two millennia was sampled at two intervals, with ages corresponding to 140 (S1) and 1400 (S2) yr BP. High-throughput sequencing showed an abundance of Bacillus, Micrococcus, unclassified members of Planococcaceae, Anaerolineaceae, Planctomycetaceae, Microlunatus, and Microbacterium in both intervals, with slight differences in their abundance, along with newly detected ones in S2, i.e., Propionibacterium, Fictibacillus, Thalassobacillus, and Bacteroides. Canonical correspondence analysis (CCA) and co-occurrence patterns confirmed strong correlations among the taxa and the environmental parameters, suggesting either shared and preferred environmental conditions, or the performance of functions similar to or complementary to each other. These results were further confirmed using culture-dependent methods. The diversity of the culturable bacterial community revealed a predominance of Bacillus, and Micrococcus or Kocuria. The interaction of these bacterial communities with selected heavy metals (Cu, Cr, Zn and Pb) was also investigated, and their capacity of bioaccumulating metals within the cells and/or in the extracellular polymeric substances (EPS) is demonstrated. Interestingly, biomineralization of Pb resulted in the precipitation of Pb phosphates (pyromorphite). Our study supports that remnants of marine bacterial communities can survive in deep-sea sediments over thousands of years. This is extremely important in terms of bioremediation, in particular when considering possible environmentally friendly strategies to bioremediate inorganic contaminants.


Assuntos
Metais Pesados/análise , Monitoramento Ambiental , Sedimentos Geológicos , Mar Mediterrâneo , Poluentes Químicos da Água
13.
Nutrients ; 11(7)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295866

RESUMO

The prevalence of degenerative diseases has risen in western countries. Growing evidence suggests that demenia and other cognition affectations are associated with ambient factors including specific nutrients, food ingredients or specific dietary patterns. Mediterranean diet adherence has been associated with various health benefits and decreased risk of many diseases, including neurodegenerative disorders. Beer, as part of this protective diet, contains compounds such as silicon and hops that could play a major role in preventing brain disorders. In this review, different topics regarding Mediterranean diet, beer and the consumption of their main compounds and their relation to neurological health have been addressed. Taking into account published results from our group and other studies, the hypothesis linking aluminum intoxication with dementia and/or Alzheimer's disease and the potential role of regular beer has also been considered. Beer, in spite of its alcohol content, may have some health benefits; nonetheless, its consumption is not adequate for all subjects. Thus, this review analyzed some promising results of non-alcoholic beer on several mechanisms engaged in neurodegeneration such as inflammation, oxidation, and cholinesterase activity, and their contribution to the behavioral modifications induced by aluminum intoxication. The review ends by giving conclusions and suggesting future topics of research related to moderate beer consumption and/or the consumption of its major compounds as a potential instrument for protecting against neurodegenerative disease progression and the need to develop nutrigenetic and nutrigenomic studies in aged people and animal models.


Assuntos
Doença de Alzheimer , Cerveja , Dieta Mediterrânea , Neuroproteção , Alumínio , Humanos , Valor Nutritivo , Silício
14.
Cell Mol Life Sci ; 76(12): 2299-2328, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877334

RESUMO

The appearance of modular proteins is a widespread phenomenon during the evolution of proteins. The combinatorial arrangement of different functional and/or structural domains within a single polypeptide chain yields a wide variety of activities and regulatory properties to the modular proteins. In this review, we will discuss proteins, that in addition to their catalytic, transport, structure, localization or adaptor functions, also have segments resembling the helix-loop-helix EF-hand motifs found in Ca2+-binding proteins, such as calmodulin (CaM). These segments are denoted CaM-like domains (CaM-LDs) and play a regulatory role, making these CaM-like proteins sensitive to Ca2+ transients within the cell, and hence are able to transduce the Ca2+ signal leading to specific cellular responses. Importantly, this arrangement allows to this group of proteins direct regulation independent of other Ca2+-sensitive sensor/transducer proteins, such as CaM. In addition, this review also covers CaM-binding proteins, in which their CaM-binding site (CBS), in the absence of CaM, is proposed to interact with other segments of the same protein denoted CaM-like binding site (CLBS). CLBS are important regulatory motifs, acting either by keeping these CaM-binding proteins inactive in the absence of CaM, enhancing the stability of protein complexes and/or facilitating their dimerization via CBS/CLBS interaction. The existence of proteins containing CaM-LDs or CLBSs substantially adds to the enormous versatility and complexity of Ca2+/CaM signaling.


Assuntos
Calmodulina/química , Motivos EF Hand , Proteínas/química , Actinina/química , Actinina/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Calcineurina/química , Calcineurina/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio , Calmodulina/metabolismo , Calpaína/química , Calpaína/metabolismo , Humanos , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Proteínas Quinases/química , Proteínas Quinases/metabolismo , Proteínas/metabolismo
15.
Food Chem ; 277: 353-361, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30502157

RESUMO

The non-isothermal autohydrolysis temperature impact of edible brown seaweed Laminaria ochroleuca was studied to recover high valuable compounds. Extraction yield was determined, above 80% was obtained at 220 °C. The maximal fucose content (17% d.b.) was attained at 180 °C, whereas the maximal sulphate was achieved at 160 °C, and phenolic and protein content at 220 °C. The maximum sulphated fucoidan content (41.38 g fucoidan/100 g extract) was obtained at 160 °C, whereas the maximum fucose oligosaccharides was obtained at 180 °C. The antioxidant capacity was equivalent to 32 mg Trolox/g dry extract produced at 220 °C. The milder processing condition was selected to study the potentiality of the precipitated alginate in terms of viscoelastic properties determined by rheology. Alginate extraction (14.94 g/100 g extract) was determined at 160 °C. The crude fucoidan fractions were tested at 25-500 µg/mL, showed up to 50% cell growth inhibition in four selected tumoral cell lines.


Assuntos
Géis/química , Laminaria/química , Alga Marinha/química , Células A549 , Alginatos/análise , Alginatos/farmacologia , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/análise , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Fenômenos Químicos , Cromanos/análise , Cromanos/farmacologia , Inibidores do Crescimento/análise , Inibidores do Crescimento/farmacologia , Células HCT116 , Temperatura Alta , Humanos , Hidrólise , Peso Molecular , Polissacarídeos/farmacologia , Reologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Nutrients ; 10(12)2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30486328

RESUMO

Restructuring pork (RP) by adding new functional ingredients, like Chia oil (one of the richest natural source of α-linolenic acid) or hydroxytyrosol (HxT) (potent antioxidant), both with hypolipidemic activities, is one of the strategies that may help to reduce the potential negative effects of high meat products consumption. The aim of this study was to evaluate the Chia oil- or HxT-enriched-RP effect on the lipoprotein profile of aged rats fed high-fat, high-energy, and cholesterol-enriched diets. RP samples were prepared by mixing lean pork and lard with or without Chia oil (152.2 g/kg fresh matter) or HxT (3.6 g/kg fresh matter). Diets were prepared by mixing a semisynthetic diet with freeze-dried RP. Groups of 1-year male Wistar rats were fed the following experimental diets for 8 weeks: C, control-RP diet; HC, cholesterol-enriched-RP diet; and Chia oil-RP (CHIA) and HxT, Chia oil- or hydroxytyrosol-RP, cholesterol-enriched diet. Plasma lipid, lipoprotein profile, SREBP-1c protein, and low-density lipoproteins (LDL) receptor gene (Ldlr) expressions were evaluated. Compared to C diet, the HC diet increased plasma cholesterol, triglycerides, free fatty acids, total lipids, and SREBP-1c expression, but reduced Ldlr expression and significantly modified the lipoprotein profile, giving rise to the presence of high levels of atherogenic cholesterol-enriched very low-density lipoproteins (VLDL) particles. Compared to the HC diet, the HxT diet did not produce significant changes in feed intake but it reduced the body weight. Chia oil and HxT partially arrested the negative effects of the high-fat, high-energy, and cholesterol-enriched meat-based diets on lipemia and lipoproteinemia, mostly by reducing the amount of cholesterol content in VLDL (60% and 74% less in CHIA and HxT vs. HC, respectively) and the VLDL total mass (59% and 63% less in CHIA and HxT vs. HC, respectively). Free fatty acids (FFA) significantly correlated with adipose tissue weight and VLDL total mass (both p < 0.05), and plasma triglycerides, phospholipids, total lipids, and SREBP-1c (all p < 0.001), suggesting the important role of FFA in lipoprotein metabolism. Results support the recommendation to include these ingredients in pork products addressed to reduce the presence of increased atherogenic particles in aged people at CVD risk consuming large amounts of pork.


Assuntos
Colesterol na Dieta/sangue , Dieta Hiperlipídica , Lipoproteínas LDL/sangue , Álcool Feniletílico/análogos & derivados , Óleos de Plantas/farmacologia , Carne Vermelha , Salvia/química , Tecido Adiposo , Animais , Antioxidantes/farmacologia , Colesterol na Dieta/administração & dosagem , Ácidos Graxos/sangue , Lipoproteínas VLDL/sangue , Masculino , Álcool Feniletílico/farmacologia , Fosfolipídeos/sangue , Óleos de Plantas/metabolismo , Ratos Wistar , Receptores de LDL/sangue , Sementes , Proteína de Ligação a Elemento Regulador de Esterol 1/sangue , Suínos , Triglicerídeos/sangue , Ácido alfa-Linolênico/sangue , Ácido alfa-Linolênico/farmacologia
17.
Nat Commun ; 9(1): 1619, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29691412

RESUMO

Ba proxies have been broadly used to reconstruct past oceanic export production. However, the precise mechanisms underlying barite precipitation in undersaturated seawater are not known. The link between bacterial production and particulate Ba in the ocean suggests that bacteria may play a role. Here we show that under experimental conditions marine bacterial biofilms, particularly extracellular polymeric substances (EPS), are capable of bioaccumulating Ba, providing adequate conditions for barite precipitation. An amorphous P-rich phase is formed at the initial stages of Ba bioaccumulation, which evolves into barite crystals. This supports that in high productivity regions where large amounts of organic matter are subjected to bacterial degradation, the abundant EPS would serve to bind the necessary Ba and form nucleation sites leading to barite precipitation. This also provides new insights into barite precipitation and opens an exciting field to explore the role of EPS in mineral precipitation in the ocean.


Assuntos
Bactérias/metabolismo , Bário/metabolismo , Biopolímeros/metabolismo , Bactérias/química , Bário/química , Biofilmes , Biopolímeros/química , Água do Mar/análise , Água do Mar/microbiologia
18.
Electrophoresis ; 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29460953

RESUMO

Cantharellus tubaeformis was processed by pressurized hot water extraction (80-240°C) with the aim of maximizing the extraction of oligomeric fractions, ß-glucans, and the in vitro antioxidant properties of the extracts. Increased severity of treatment enhanced the extraction yields above 62% at temperatures of 210ºC or higher, corresponding to the maximum ß-glucan yields. The highest antioxidant capacity was obtained at 170ºC, although the highest content of phenolic compounds was obtained at the highest severity studied. This hydrothermal treatment can be considered a suitable process to obtain extracts with antioxidant properties and rich in ß-glucans.

19.
Food Res Int ; 103: 130-149, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29389599

RESUMO

Ursolic acid (UA) is a pentacyclic triterpenoid widely found in herbs, leaves, flowers and fruits; update information on the major natural sources or agro-industrial wastes is presented. Traditional (maceration, Soxhlet and heat reflux) and modern (microwave-, ultrasound-, accelerated solvent- and supercritical fluid) extraction and purification technologies of UA, as well as some patented process, are summarized. The great interest in this bioactive compound is related to the beneficial effects in human health due to antioxidant, antimicrobial, anti-inflammatory, hepatoprotective, immunomodulatory, anti-tumor, chemopreventive, cardioprotective, antihyperlipidemic and hypoglycemic activities, and others. UA may augment the resistance of the skin barrier to irritants, prevent dry skin and could be suitable to develop antiaging products. The development of nanocrystals and nanoparticle-based drugs could reduce the side effects of high doses of UA in organisms, and increase its limited solubility and poor bioavailability of UA which limit the potential of this bioactive and the further applications. Commercial patented applications in relation to cosmetical and pharmaceutical uses of UA and its derivatives are surveyed.


Assuntos
Fracionamento Químico/métodos , Cosméticos/uso terapêutico , Suplementos Nutricionais , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Triterpenos/isolamento & purificação , Triterpenos/uso terapêutico , Animais , Qualidade de Produtos para o Consumidor , Cosméticos/efeitos adversos , Cosméticos/isolamento & purificação , Suplementos Nutricionais/efeitos adversos , Humanos , Segurança do Paciente , Extratos Vegetais/efeitos adversos , Medição de Risco , Triterpenos/efeitos adversos , Ácido Ursólico
20.
Environ Sci Pollut Res Int ; 24(30): 23666-23678, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28861694

RESUMO

Human biomonitoring can be a reliable tool to protect the health of the citizens of major urban environments. Human hair may be an invaluable specimen to determine chronic exposure to any environmental contaminant in an individual, especially in the young population. However, different factors including a lack of studies that have established reference values for metals and metalloids (trace elements) in human scalp hair make the use of this matrix controversial. A monitoring study was performed to establish possible normal or tentative reference values of Al, As, Be, Cd, Cr, Cu, Hg, Mn, Pb, Sn, Ti, Tl and Zn in adolescents' (aged 13-16) hair who have lived since birth in Alcalá de Henares, Madrid region (Spain). Strict inclusion criteria were followed to study the effect of sex on the hair metal content, and the levels of the above contaminants were also studied in park topsoils from Alcalá de Henares. Scalp hair samples were collected from 96 healthy adolescents (28 boys and 68 girls), and reference values were calculated following the recommendations of the International Union of Pure and Applied Chemistry. The levels of Cd, Cu, Pb, Sn and Zn in hair of adolescents from Alcalá de Henares show a sex dependency, being significantly higher in female participants. Sex should be a factor taken into account when developing future reference values and hair metal content. Soil metal contamination was not correlated with the levels found in hair. To conclude, the values of metals and metalloids here analysed and discussed could be considered as tentative reference values for Spanish adolescents aged 13-16 years living in the Madrid region, and may be used to identify the level of exposure of adolescents in this Spanish region to the various metals and metalloids.


Assuntos
Cabelo/química , Mercúrio/análise , Metaloides/análise , Metais/análise , Couro Cabeludo/química , Oligoelementos/análise , Adolescente , Monitoramento Ambiental , Humanos , Valores de Referência , Espanha
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