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1.
Food Chem ; 304: 125448, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491713

RESUMO

Blood, from slaughterhouses, is an inevitable part of meat production, causing environmental problems due to the large volumes recovered and its low valorization. However, the α137-141 peptide, a natural antimicrobial peptide, can be obtained after hydrolysis of hemoglobin, the main constituent of blood red part. To recover it at a sufficient concentration for antimicrobial applications, a new sustainable technology, called electrodialysis with ultrafiltration membrane (EDUF), was investigated. The α137-141 concentration was increased about 4-fold at a feed peptide concentration of 8% with an enrichment factor above 24-fold. This feed peptide concentration also needed the lowest relative energy consumption. Moreover, this peptide fraction protected meat against microbial growth, as well as rancidity, during 14 days under refrigeration. This peptide fraction was validated as a natural preservative and substitute for synthetic additives against food spoilage. Finally, producing antimicrobial/antioxidant peptide from wastes by EDUF fits perfectly with the concept of circular economy.

2.
Mar Drugs ; 17(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671730

RESUMO

The term metabolic/cardiometabolic/insulin resistance syndrome could generally be defined as the co-occurrence of several risk factors inclusive of systemic arterial hypertension. Not only that organizations, such as the world health organization (WHO) have identified high blood pressure as one of the main risk factors of the cardiometabolic syndrome, but there is also a link between the occurrence of insulin resistance/impaired glucose tolerance and hypertension that would consequently lead to type-2 diabetes (T2D). Hypertension is medicated by various classes of synthetic drugs; however, severe or mild adverse effects have been repeatedly reported. To avoid and reduce these adverse effects, natural alternatives, such as bioactive peptides derived from different sources have drawn the attention of researchers. Among all types of biologically active peptides inclusive of marine-derived ones, this paper's focus would solely be on fish and fishery by-processes' extracted peptides and products. Isolation and fractionation processes of these products alongside their structural, compositional and digestion stability characteristics have likewise been briefly discussed to better address the structure-activity relationship, expanding the reader's knowledge on research and discovery trend of fish antihypertensive biopeptides. Furthermore, drug-likeness of selected biopeptides was predicted by Lipinski's rules to differentiate a drug-like biopeptide from nondrug-like one.

3.
Sci Total Environ ; 690: 400-409, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302538

RESUMO

Natural organic matter (NOM) is removed from potable water for aesthetic, operational and indirect health concerns. NOM removal via ion exchange (IX) resins is receiving increasing attention owing to its simple operation. However, production of a spent brine during IX regeneration is the main drawback due to strict discharge regulations and limited and costly brine management options. In this study, the viability of desalinating the IX brine was assessed via electrodialysis (ED). ED desalination of the IX brine led to the production of highly pure NaCl and NOM-rich solutions which can be used for the IX regeneration and agricultural applications, respectively. Of particular interests were the impacts of the membrane permselectivity and implementation of pulsed electric field (PEF) on membrane fouling, desalination, purity of the NaCl solution and energy consumption. Our results demonstrated that ED desalination with monovalent ion permselective membranes consumed approximately 2 Wh per g of produced NaCl, achieved 88.8% desalination, produced pure NaCl solution with negligible membrane fouling. Furthermore, for the first time, we demonstrated that the PEF-ED intensified the process and decreased membrane fouling only when the conventional ion-exchange membranes were used; while no significant difference was detected when the PEF-ED was operated with the monovalent ion permselective membranes.

4.
Mar Drugs ; 17(7)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336895

RESUMO

The Atlantic mackerel, Scomber scombrus, is one of the most fished species in the world, but it is still largely used for low-value products, such as bait; mainly for crustacean fishery. This resource could be transformed into products of high value and may offer new opportunities for the discovery of bioactive molecules. Mackerel hydrolysate was investigated to discover antibacterial peptides with biotechnological potential. The proteolytic process generated a hydrolysate composed of 96% proteinaceous compounds with molecular weight lower than 7 kDa. From the whole hydrolysate, antibacterial activity was detected against both Gram-negative and Gram-positive bacteria. After solid phase extraction, purification of the active fraction led to the identification of 4 peptide sequences by mass spectrometry. The peptide sequence N-KVEIVAINDPFIDL-C, called Atlantic Mackerel GAPDH-related peptide (AMGAP), was selected for chemical synthesis to confirm the antibacterial activity and to evaluate its stability through in vitro digestibility. Minimal inhibitory concentrations of AMGAP revealed that Listeria strains were the most sensitive, suggesting potential as food-preservative to prevent bacterial growth. In addition, in vitro digestibility experiments found rapid (after 20 min) and early digestibility (stomach). This study highlights the biotechnological potential of mackerel hydrolysate due to the presence of the antibacterial AMGAP peptide.

5.
Int J Mol Sci ; 20(8)2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31009989

RESUMO

The valorization of by-products from natural organic sources is an international priority to respond to environmental and economic challenges. In this context, electrodialysis with filtration membrane (EDFM), a green and ultra-selective process, was used to separate peptides from salmon frame protein hydrolysate. For the first time, the simultaneous separation of peptides by three ultrafiltration membranes of different molecular-weight exclusion limits (50, 20, and 5 kDa) stacked in an electrodialysis system, allowed for the generation of specific cationic and anionic fractions with different molecular weight profiles and bioactivity responses. Significant decreases in peptide recovery, yield, and molecular weight (MW) range were observed in the recovery compartments depending on whether peptides had to cross one, two, or three ultrafiltration membranes. Moreover, the Cationic Recovery Compartment 1 fraction demonstrated the highest increase (42%) in glucose uptake on L6 muscle cells. While, in the anionic configuration, both Anionic Recovery Compartment 2 and Anionic Recovery Compartment 3 fractions presented a glucose uptake response in basal condition similar to the insulin control. Furthermore, Cationic Recovery Compartment 3 was found to contain inhibitory peptides. Finally, LC-MS analyses of the bioassay-guided bioactive fractions allowed us to identify 11 peptides from salmon by-products that are potentially responsible for the glucose uptake improvement.


Assuntos
Glucose/metabolismo , Peptídeos/isolamento & purificação , Hidrolisados de Proteína/isolamento & purificação , Salmão/metabolismo , Animais , Ânions , Cátions , Linhagem Celular , Diálise , Camundongos , Peso Molecular , Termodinâmica , Ultrafiltração
6.
Int J Mol Sci ; 20(4)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781748

RESUMO

The drying of acid whey is hindered by its high mineral and organic acid contents, and their removal is performed industrially through expensive and environmentally impacting serial processes. Previous works demonstrated the ability to remove these elements by electrodialysis alone but with a major concern-membrane scaling. In this study, two conditions of pulsed electric field (PEF) were tested and compared to conventional DC current condition to evaluate the potential of PEF to mitigate membrane scaling and to affect lactic acid and salt removals. The application of a PEF 25 s/25 s pulse/pause combination at an initial under-limiting current density allowed for decreasing the amount of scaling, the final system electrical resistance by 32%, and the relative energy consumption up to 33%. The use of pulsed current also enabled better lactic acid removal than the DC condition by 10% and 16% for PEF 50 s/10 s and 25 s/25 s, respectively. These results would be due to two mechanisms: (1) the mitigation of concentration polarization phenomenon and (2) the rinsing of the membranes during the pause periods. To the best of our knowledge, this was the first time that PEF current conditions were used on acid whey to both demineralize and deacidify it.


Assuntos
Diálise/métodos , Eletricidade , Ácido Láctico/isolamento & purificação , Minerais/isolamento & purificação , Soro do Leite/química , Cálcio/análise , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Resinas de Troca Iônica , Proteínas/análise , Soluções , Espectrometria por Raios X , Termodinâmica , Difração de Raios X
7.
Food Res Int ; 115: 467-473, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599966

RESUMO

Exploration of innovative high hydrostatic pressure (HHP)-assisted enzymatic hydrolysis of plant based food proteins may help improve peptide yield and bioactivity of hydrolysates. In this study, we performed enzymatic hydrolysis of flaxseed proteins using trypsin under HHP (100 and 300 MPa for 5 and 10 min) to evaluate the effect of presurization on protein denaturation, degree of hydrolysis (DH), and peptide profile and bioactivity of hydrolysate. Spectrofluorimetric analyses showed that 300 MPa induced the maximum destablization of flaxseed protein structures. The same pressure level drastically improved the DH by 1.7 times as compared to that of control. Applying HHP did not modify the peptide profiles of flaxseed protein hydrolysates but their concentrations increased with severity of treatment. Similarly, peptide molecular weight distributions were affected by pressurization parameters, increasing mainly the relative abundance of 500-1500 Da peptides. Finally, pressurization at 300 MPa for 5 and 10 min improved the antioxidant activity of flaxseed protein hydrolysates by 39 and 55%, respectively, compared to the control.

8.
J Dairy Sci ; 101(9): 7833-7850, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29935834

RESUMO

With the rising popularity of Greek-style yogurts in the past few years, the production of acid whey has drastically increased. If sweet whey is usually further processed, the acid whey valorization comes with challenges because its drying is jeopardized by its high mineral and organic acid contents. For this reason, prior demineralization and deacidification are usually performed at industrial scale using a combination of ion exchange resins and electrodialysis. This whole process represents large amounts of resources and energy consumption as well as an important production of effluents. The optimization of the electrodialysis technique, currently the focus of a few studies, could result in the replacement of the serial processes and would provide a cost-effective and eco-efficient alternative. In this work, the demineralization and deacidification of acid whey were compared via 2 electrodialysis configurations: one conventional and one using bipolar membranes. Both configurations allowed to reach interesting demineralization (67%) and deacidification (44%) rates. However, even though the appearance of fouling or scaling has never been reported, scalings of different natures were observed on membranes using both configurations. Amorphous calcium phosphate was identified on the anion exchange membranes for both configurations while calcite and brucite were identified on cation exchange ones using the bipolar membrane configuration. These scaling formations were linked to the migration of divalent ions and water splitting phenomenon caused by a high demineralization rate or by an already formed significant scaling.

9.
J Dairy Sci ; 101(8): 7002-7012, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29753479

RESUMO

Finding new environmentally friendly ways of producing proteins has never been of such critical public interest, both to meet consumers' needs and to preserve the environment. Milk proteins are among the most attractive protein types due to their high nutritional value and attractive functional properties. In this work, the separation of caseins by conventional chemical acidification was compared with electrodialysis with bipolar membrane coupled to an ultrafiltration module (EDBM-UF), a green process that allows the precipitation of caseins by H+ generated in situ by the bipolar membrane and, simultaneously, the production of a separated NaOH stream from OH- electrogenerated by the bipolar membrane. Caseinate production using this NaOH stream by-product and the quantity of NaOH needed to produce caseinates from both methods were also investigated. Hence, the purity and composition of caseins and caseinates were compared in terms of protein, ash, and lactose contents as well as mineral composition. The results showed for the first time that caseinates can be produced by solubilizing caseins with NaOH stream from the EDBM process. Furthermore, the caseins and caseinates produced by EDBM-UF were equivalent in terms of lactose and protein contents to their respective caseins and caseinates that were chemically produced but presented slightly lower sodium content and 3 to 4 times higher magnesium and calcium contents. The fact that calcium and magnesium are likely bound to milk caseins would ensure their favorable absorbability. These caseins or caseinates from the new EDBM-UF process could be suitable as an improved protein-based calcium or magnesium supplement, both for their enhanced nutritional quality and because they are produced by a "green" process.

10.
Hypertens Pregnancy ; 37(2): 68-80, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29658370

RESUMO

OBJECTIVES: The aim of this 2-group, parallel, double blind single-centre RCT was to evaluate the acute and chronic impacts of high flavanol high theobromine (HFHT) chocolate consumption on endothelial function, arterial stiffness and blood pressure (BP) in women at risk of preeclampsia. METHODS: 131 pregnant women considered at risk of preeclampsia based on uterine artery Doppler ultrasound were divided into two groups (HFHT or low flavanol and theobromine chocolate (LFLT). Acute changes in plasma flavanol and theobromine, peripheral arterial tonometry and BP were evaluated at randomization (0, 60 and 120 min after a single 40-g dose of chocolate) and again 6 and 12 weeks after daily 30-g chocolate intake. The EndoPAT 2000 provided reactive hyperemia index (RHI) and adjusted augmentation index (AIx) as markers for endothelial function and arterial stiffness, respectively. RESULTS: Compared with LFLT, acute HFHT intake significantly increased plasma epicatechin and theobromine (p < 0.0001), decreased AIx (p < 0.0001) and increased diastolic BP (3.49 ± 3.40 mmHg increase in HFHT group vs 1.55 ± 2.59 mmHg increase in LFLT group, p = 0.0008). Chronic HFHT compared with LFLT intake significantly increased plasma theobromine (p < 0.0001). No other significant within group or between group changes were observed. CONCLUSIONS: Acute consumption of HFHT, compared to LFLT, increased plasma epicatechin and theobromine concentrations and decreased arterial stiffness, with no effect on endothelial function and a marginal increase in diastolic BP. Chronic HFHT intake increased plasma theobromine, though it did not have positive impacts on endothelial function, arterial stiffness or BP when compared to LFLT in pregnant women at risk of PE.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Chocolate , Endotélio Vascular/efeitos dos fármacos , Teobromina/administração & dosagem , Rigidez Vascular/efeitos dos fármacos , Adulto , Método Duplo-Cego , Feminino , Humanos , Gravidez , Artéria Uterina/diagnóstico por imagem
11.
J Colloid Interface Sci ; 508: 488-499, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28865343

RESUMO

Polypeptide/solid charged surface interactions are omnipresent in the biomedical and biochemical fields. The present study aimed to understand the adsorption mechanisms of a cation-exchange membrane (CEM) by a well-characterized peptide mixture at three different pH values. Results demonstrated that fouling was important at pH 6, twice lower at pH 2 and negligible at pH 10. At pH 6, ALPMHIR and TKIPAVFK sequences firstly established electrostatic interactions with the negative CEM charges (SO3-) through their positive K and R residues (NH3+) creating a first nanolayer. Secondly, peptide/peptide interactions occurred through their respective hydrophobic residues creating a second nanolayer. At pH 2, VLVLDTDYK and IDALNENK sequences interacted only electrostatically and that in a lower proportion since at acidic pH values, most of the CEM charges would be protonated and uncharged (HSO3) and then limit the potential electrostatic interactions. In addition, the sequences of peptides interacting at pH 2 and 6 were different. This was explained by their structure in terms of residue nature and position in the sequence. At pH 10, no fouling was observed due to the lack of positive peptide charges. To the best of our knowledge, it is the first in-depth study concerning the fouling of CEMs by peptides from a complex mixture.

12.
J Dairy Sci ; 100(9): 7071-7082, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28647330

RESUMO

Ultrafiltration (UF) is largely used in the dairy industry to generate milk and whey protein concentrate for standardization of milk or production of dairy ingredients. Recently, it was demonstrated that high hydrostatic pressure (HHP) extended the shelf life of milk and improved rennet coagulation and cheese yield. Pressurization also modified casein micelle size distribution and promoted aggregation of whey proteins. These changes are likely to affect UF performance. Consequently, this study determined the effect of skim milk pressurization (300 and 600 MPa, 5 min) on UF performance in terms of permeate flux decline and fouling. The effect of HHP on milk proteins was first studied and UF was performed in total recycle mode at different transmembrane pressures to determine optimal UF operational parameters and to evaluate the effect of pressurization on critical and limiting fluxes. Ultrafiltration was also performed in concentration mode at a transmembrane pressure of 345 kPa for 130 or 140 min to evaluate the decline of permeate flux and to determine fouling resistances. It was observed that average casein micelle size decreased by 32 and 38%, whereas ß-lactoglobulin denaturation reached 30 and 70% at 300 and 600 MPa, respectively. These results were directly related to UF performance because initial permeate fluxes in total recycle mode decreased by 25% at 300 and 600 MPa compared with nonpressurized milk, critical flux, and limiting flux, which were lower during UF of milk treated with HHP. During UF in concentration mode, initial permeate fluxes were 30% lower at 300 and 600 MPa compared with the control, but the total flux decline was higher for nonpressurized milk (62%) compared with pressure-treated milk (30%). Fouling resistances were similar, whatever the treatment, except at 600 MPa where irreversible fouling was higher. Characterization of the fouling layer showed that caseins and ß-lactoglobulin were mainly involved in membrane fouling after UF of pressure-treated milk. Our results demonstrate that HHP treatment of skim milk drastically decreased UF performance.


Assuntos
Pressão Hidrostática , Proteínas do Leite/química , Leite/química , Ultrafiltração , Animais , Manipulação de Alimentos
13.
Crit Rev Food Sci Nutr ; 57(4): 677-700, 2017 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25674704

RESUMO

Antioxidants molecules have a great interest for bio-food and nutraceutical industries since they play a vital role for their capacity to reduce oxidative processes. Consequently, these molecules, generally present in complex matrices, have to be fractionated and purified to characterize them and to test their antioxidant activity. However, as natural or synthetics antioxidant molecules differ in terms of structural composition and physico-chemical properties, appropriate separation technologies must be selected. Different fractionation technologies are available but the most commonly used are filtration processes. Indeed, these technologies allow fractionation according to molecular size (pressure-driven processes), charge, or both size and charge (electrically driven processes). In this context, and after summarizing the reaction mechanisms of the different classes and nature of antioxidants as well as membrane fractionation technologies, this manuscript presents the specific applications of these membranes processes for the recovery of antioxidant molecules.


Assuntos
Antioxidantes/farmacologia , Tecnologia de Alimentos/métodos , Antioxidantes/química , Biotecnologia/métodos , Humanos , Membranas Artificiais
14.
Food Chem ; 221: 1805-1812, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979166

RESUMO

The effect of high hydrostatic pressure (HHP) on flaxseed protein structure and peptide profiles, obtained after protein hydrolysis, was investigated. Isolated flaxseed protein (1%, m/v) was subjected to HHP (600MPa, 5min or 20min at 20°C) prior to hydrolysis with trypsin only and trypsin-pronase. The results demonstrated that HHP treatment induced dissociation of flaxseed proteins and generated higher molecular weight aggregates as a function of processing duration. Fluorescence spectroscopy showed that HHP treatment, as well as processing duration, had an impact on flaxseed protein structure since exposition of hydrophobic amino acid tyrosine was modified. Except for some specific peptides, the concentrations of which were modified, similar peptide profiles were obtained after hydrolysis of pressure-treated proteins using trypsin. Finally, hydrolysates obtained using trypsin-pronase had a greater antioxidant capacity (ORAC) than control samples; these results confirmed that HHP enhanced the generation of antioxidant peptides.


Assuntos
Antioxidantes/química , Linho/química , Proteínas de Plantas/química , Hidrolisados de Proteína/química , Aminoácidos/metabolismo , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Pressão Hidrostática , Peso Molecular , Tamanho da Partícula , Peptídeos/química , Tripsina/metabolismo
15.
J Colloid Interface Sci ; 488: 39-47, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27821338

RESUMO

Integrated forest biorefinery offers promising pathways to sustainably diversify the revenue of pulp and paper industry. In this context, lignin can be extracted from a residual stream of Kraft pulping process, called black liquor, and subsequently converted into a wide spectrum of bio-based products. Electrochemical acidification of Kraft black liquor by electrodialysis with bipolar membrane results in lignin extraction and caustic soda production. Even though the implementation of this method requires less chemicals than the chemical acidification process, fouling of the ion exchange membranes and especially bipolar membrane impairs its productivity. Membrane thickness and ash content measurements along with scanning electron microscopy (SEM), elemental analysis (EDX) and X-ray photoelectron spectrometry (XPS) analysis were performed to identify the nature and mechanisms of the membrane fouling. The results revealed that the fouling layer mostly consisted of organic components and particularly lignin. Based on our proposed fouling mechanisms, throughout the electrodialysis process the pH of the black liquor gradually decreased and as a result more proton ions were available to trigger protonation reaction of lignin phenolic groups and decrease the lignin solubility. Due to the abundance of the proton ions on the surface of the cation exchange layers of the bipolar membrane, destabilized lignin macro-molecules started to self-aggregate and formed lignin clusters on its surface. Over the time, these lignin clusters covered the entire surface of the bipolar membrane and the spaces between the membranes and, eventually, attached to the surface of the cation exchange membrane.


Assuntos
Diálise/instrumentação , Técnicas Eletroquímicas/instrumentação , Análise de Falha de Equipamento , Lignina/química , Prótons , Concentração de Íons de Hidrogênio , Troca Iônica , Membranas Artificiais , Papel , Hidróxido de Sódio/química
16.
Food Funct ; 7(3): 1634-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26931486

RESUMO

Green tea polyphenols are recognized for their antioxidant properties and their effects on lipid digestion kinetics. Polyphenols are sensitive to degradation in the intestinal environment. Interactions with dairy proteins could modulate the stability and biological activity of polyphenols during digestion. The objective of this study was to evaluate the release of nutrients (polyphenols, fatty acids and peptides) and the antioxidant activity in polyphenol-enriched cheese containing different levels of calcium in a simulated gastrointestinal environment. The relationship between cheese matrix texture, matrix degradation and nutrient release during digestion was also studied. Green tea extract was added to milk at 0% or 0.1%, and cheeses were produced on a laboratory scale. The level of available calcium was adjusted to low (Ca(low)), regular (Ca(reg)) or high (Ca(high)) during the salting step of the cheese-making process. Cheeses were subjected to simulated digestion. The rate and extent of fatty acid release were 21% lower for Ca(low) cheese than for Ca(reg) and Ca(high) cheeses. The greater adhesiveness of Ca(low) cheese, which resulted in lower rates of matrix degradation and proteolysis, contributed to the reduced rate of lipolysis. The presence of green tea extract in cheese reduced the release of free fatty acids at the end of digestion by 7%. The addition of green tea extract increased cheese hardness but did not influence matrix degradation or proteolysis profiles. The formation of complexes between tea polyphenols and proteins within the cheese matrix resulted in a more than twofold increase in polyphenol recovery in the intestinal phase compared with the control (tea polyphenol extract incubated with polyphenol-free cheese). Antioxidant activity was 14% higher in the digest from polyphenol-enriched cheese than in the control. These results suggest that cheese is an effective matrix for the controlled release of nutrients and for the protection of green tea polyphenol integrity and biological activity in the gastrointestinal environment.


Assuntos
Antioxidantes/metabolismo , Queijo/análise , Digestão , Aditivos Alimentares/metabolismo , Trato Gastrointestinal/metabolismo , Extratos Vegetais/metabolismo , Polifenóis/metabolismo , Antioxidantes/química , Cálcio/química , Cálcio/metabolismo , Aditivos Alimentares/química , Humanos , Concentração de Íons de Hidrogênio , Cinética , Modelos Biológicos , Extratos Vegetais/química , Polifenóis/química
17.
Int J Food Sci Nutr ; 67(3): 298-304, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26960683

RESUMO

Interactions between ß-lactoglobulin (ß-lg) and epigallocatechin-3-gallate (EGCG) may modulate their health benefits. The objective of this study was therefore to investigate the synergistic effect of consuming ß-lg and EGCG complexes on glucose tolerance of C57BL/6 male mice given an oral glucose tolerance test (OGTT) and randomized to one of the following treatments administered prior to the OGTT: 1) simulated milk ultrafiltrate (SMUF(-)), 2) SMUF(-) + EGCG, 3) SMUF(-) + ß-lg, 4) SMUF(-) + EGCG + ß-lg, 5) SMUF + calcium (SMUF(+)) and 6) SMUF(+) + EGCG + ß-lg. We found no significant between-group difference in postprandial glucose response. However, when mice were separated in those who received ß-lg from those who did not, we found that the latter displayed significantly higher postprandial glucose concentrations. Our results support the beneficial impact of ß-lg on glycemic control and suggest that concomitant EGCG or calcium consumption does not improve this effect.


Assuntos
Cálcio/farmacologia , Catequina/análogos & derivados , Intolerância à Glucose/prevenção & controle , Glucose/administração & dosagem , Lactoglobulinas/farmacologia , Animais , Glicemia , Cálcio/administração & dosagem , Catequina/administração & dosagem , Catequina/farmacologia , Glucose/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
18.
Adv Colloid Interface Sci ; 229: 34-56, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26813627

RESUMO

The environmentally friendly ion-exchange membrane (IEM) processes find more and more applications in the modern industries in order to demineralize, concentrate and modify products. Moreover, these processes may be applied for the energy conversion and storage. However, the main drawback of the IEM processes is a formation of fouling, which significantly decreases the process efficiency and increases the process cost. The present review is dedicated to the problematic of IEM fouling phenomena. Firstly, the major types of IEM fouling such as colloidal fouling, organic fouling, scaling and biofouling are discussed along with consideration of the main factors affecting fouling formation and development. Secondly, the review of the possible methods of IEM fouling characterization is provided. This section includes the methods of fouling visualization and characterization as well as methods allowing investigations of characteristics of the fouled IEMs. Eventually, the reader will find the conventional and modern strategies of prevention and control of different fouling types.


Assuntos
Incrustação Biológica/prevenção & controle , Membranas Artificiais , Troca Iônica
19.
Food Chem ; 197(Pt A): 1008-14, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26617047

RESUMO

Rapeseed protein isolate was subjected to alcalase digestion to obtain a protein hydrolysate that was separated into peptide fractions using electrodialysis with ultrafiltration membrane (EDUF) technology. The EDUF process (6h duration) led to isolation of three peptide fractions: anionic (recovered in KCl-1 compartment), cationic (recovered in KCl-2 compartment), and those that remained in the feed compartment, which was labeled final rapeseed protein hydrolysate (FRPH). As expected the KCl-1 peptides were enriched in negatively-charged (43.57%) while KCl-2 contained high contents of positively-charged (28.35%) amino acids. All the samples inhibited angiotensin converting enzyme (ACE) and renin activities in dose-dependent manner with original rapeseed protein hydrolysate having the least ACE-inhibitory IC50 value of 0.0932±0.0037 mg/mL while FRPH and KCl-2 had least renin-inhibitory IC50 values of 0.47±0.05 and 0.55±0.06 mg/mL, respectively. Six hours after oral administration (100 mg/kg body weight) to spontaneously hypertensive rats, the FRPH produced the maximum systolic blood pressure reduction of -51 mmHg.


Assuntos
Anti-Hipertensivos/análise , Brassica rapa/química , Peptídeos/análise , Hidrolisados de Proteína/análise , Inibidores da Enzima Conversora de Angiotensina/análise , Inibidores da Enzima Conversora de Angiotensina/química , Animais , Pressão Sanguínea/efeitos dos fármacos , Diálise , Masculino , Peptidil Dipeptidase A/farmacologia , Ratos , Ratos Endogâmicos SHR , Renina/antagonistas & inibidores , Ultrafiltração
20.
J Nutr ; 145(7): 1415-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25995281

RESUMO

BACKGROUND: We previously reported that fish proteins can alleviate metabolic syndrome (MetS) in obese animals and human subjects. OBJECTIVES: We tested whether a salmon peptide fraction (SPF) could improve MetS in mice and explored potential mechanisms of action. METHODS: ApoB(100) only, LDL receptor knockout male mice (LDLR(-/-)/ApoB(100/100)) were fed a high-fat and -sucrose (HFS) diet (25 g/kg sucrose). Two groups were fed 10 g/kg casein hydrolysate (HFS), and 1 group was additionally fed 4.35 g/kg fish oil (FO; HFS+FO). Two other groups were fed 10 g SPF/kg (HFS+SPF), and 1 group was additionally fed 4.35 g FO/kg (HFS+SPF+FO). A fifth (reference) group was fed a standard feed pellet diet. We assessed the impact of dietary treatments on glucose tolerance, adipose tissue inflammation, lipid homeostasis, and hepatic insulin signaling. The effects of SPF on glucose uptake, hepatic glucose production, and inducible nitric oxide synthase activity were further studied in vitro with the use of L6 myocytes, FAO hepatocytes, and J774 macrophages. RESULTS: Mice fed HFS+SPF or HFS+SPF+FO diets had lower body weight (protein effect, P = 0.024), feed efficiency (protein effect, P = 0.018), and liver weight (protein effect, P = 0.003) as well as lower concentrations of adipose tissue cytokines and chemokines (protein effect, P ≤ 0.003) compared with HFS and HFS+FO groups. They also had greater glucose tolerance (protein effect, P < 0.001), lower activation of the mammalian target of rapamycin complex 1/S6 kinase 1/insulin receptor substrate 1 (mTORC1/S6K1/IRS1) pathway, and increased insulin signaling in liver compared with the HFS and HFS+FO groups. The HFS+FO, HFS+SPF, and HFS+SPF+FO groups had lower plasma triglycerides (protein effect, P = 0.003; lipid effect, P = 0.002) than did the HFS group. SPF increased glucose uptake and decreased HGP and iNOS activation in vitro. CONCLUSIONS: SPF reduces obesity-linked MetS features in LDLR(-/-)/ApoB(100/100) mice. The anti-inflammatory and glucoregulatory properties of SPF were confirmed in L6 myocytes, FAO hepatocytes, and J774 macrophages.


Assuntos
Dislipidemias/tratamento farmacológico , Proteínas de Peixes/farmacologia , Intolerância à Glucose/metabolismo , Inflamação/tratamento farmacológico , Obesidade/tratamento farmacológico , Tecido Adiposo/metabolismo , Adiposidade , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Glicemia/metabolismo , Peso Corporal , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Ingestão de Energia , Óleos de Peixe/administração & dosagem , Proteínas de Peixes/química , Insulina/sangue , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Knockout , Peso Molecular , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Salmão , Sacarose/administração & dosagem , Sacarose/efeitos adversos , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
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