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Palmaria palmata is a viable source of nutrients with bioactive properties. The present study determined the potential role of post-extraction ultrasonication on some compositional features and antioxidant properties of enzymatic/alkaline extracts of P. palmata (EAEP). No significant difference was detected in terms of protein content and recovery, as well as the amino acid composition of the extracts. The nitrogen-to-protein conversion factor of 5 was found to be too high for the seaweed and EAEP. The extracts sonicated by bath for 10 min and not sonicated showed the highest and lowest total phenolic contents (p < 0.05), respectively. The highest radical scavenging and lowest metal-chelating activities were observed for the non-sonicated sample, as evidenced by IC50 values. The extract sonicated by bath for 10 min showed the most favorable in vitro antioxidant properties since its radical scavenging was not significantly different from that of the not-sonicated sample (p > 0.05). In contrast, its metal-chelating activity was significantly higher (p < 0.05). To conclude, post-extraction ultrasonication by an ultrasonic bath for 10 min is recommended to increase phenolic content and improve the antioxidant properties of EAEP.
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Antioxidantes , Quelantes , Fenoles , Extractos Vegetales , Rhodophyta , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Quelantes/química , Algas Comestibles/química , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Fenoles/química , Fenoles/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/química , Rhodophyta/química , SonicaciónRESUMEN
The production of plant-based dairy alternatives has been majorly focused on the improvement of sensorial, technological and nutritional properties, to be able to mimic and replace milk-based fermented products. The presence of off-flavours and antinutrients, the lack of production of dairy-like flavours or the metabolic inaccessibility of plant proteins are some of the challenges to overcome to generate plant-based dairy alternatives. However, in the present study, it is demonstrated how the synergistic effect of two LAB strains, when cocultured, can simultaneously solve those challenges when fermenting in four different plant-based raw materials: soy, pea, oat, and potato drinks (SPOP). The fermentation was performed through the mono- and co-culture of the two LAB strains isolated from Apis mellifera (honeybee): Leuconostoc pseudomesenteroides NFICC 2004 and Lactococcus lactis NFICC 2005. Firstly, the coculture of both strains demonstrated to increase the acidification rate of the four plant matrices. Moreover, L. pseudomesenteroides (LP) demonstrated to in situ produce high concentrations of mannitol when fructose was present as C-source. Furthermore, L. pseudomesenteroides, which encoded for PII-proteinase, demonstrated to break down SPOP proteins, releasing free amino acids that were used by L.lactis (LL) for growth and metabolism. Lastly, the analysis of their co-metabolic volatile performance showed the principal ability of removal of the main off-flavours found in SPOP, such as hexanal, 1-octen-3-ol, 2-pentylfuran, pentanal, octanal, heptanal, and nonanal, mainly led by L. pseudomesenteroides, as well as the production of dairy-like flavours, such as diacetyl and 3-methyl-1-butanol, triggered by L. lactis metabolism. Overall, these findings endorsed the use of honeybee isolated strains as starter cultures, demonstrated the potential of coupling genotypes and phenotypes of multiple strains to improve the organoleptic properties suggesting a potential of combining plant-based matrices for the generation of future high-quality plant-based dairy alternatives.
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Lactococcus lactis , Solanum tuberosum , Abejas , Animales , Avena , Técnicas de Cocultivo , Pisum sativum , Fermentación , PlantasRESUMEN
With the aim to upcycle fish side-streams, enzymatic hydrolysis is often applied to produce protein hydrolysates with bioactive properties or just as a protein source for food and feed. However, the production of hydrolysates generates a side-stream. For underutilized fish and fish backbone this side-stream will contain fish bones and make it rich in minerals. The aim of this study was to assess the relative bioaccessibility (using the standardized in vitro model INFOGEST 2.0) of minerals in a dietary supplement compared to bone powder generated after enzymatic hydrolysis of three different fish side-streams: undersized whole hake, cod and salmon backbones consisting of insoluble protein and bones. Differences in the bioaccessibility of protein between the powders were also investigated. The enzyme hydrolysis was carried out using different enzymes and hydrolysis conditions for the different fish side-streams. The content and bioaccessibility of protein and the minerals phosphorus (P), calcium (Ca), potassium (K) and magnesium (Mg) were measured to evaluate the potential of the powder as an ingredient in, e.g., dietary supplements. The bone powders contained bioaccessible proteins and minerals. Thus, new side-streams generated from enzymatic hydrolysis can have possible applications in the food sector due to bioaccessible proteins and minerals.
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Huesos , Suplementos Dietéticos , Minerales , Alimentos Marinos , Animales , Huesos/metabolismo , Hidrólisis , Salmón/metabolismo , Disponibilidad Biológica , Proteínas de Peces/metabolismo , Peces/metabolismo , Hidrolisados de Proteína/química , PolvosRESUMEN
Enzymatic hydroxylation of fatty acids by Cytochrome P450s (CYPs) offers an eco-friendly route to hydroxy fatty acids (HFAs), high-value oleochemicals with various applications in materials industry and with potential as bioactive compounds. However, instability and poor regioselectivity of CYPs are their main drawbacks. A newly discovered self-sufficient CYP102 enzyme, BAMF0695 from Bacillus amyloliquefaciens DSM 7, exhibits preference for hydroxylation of sub-terminal positions (ω-1, ω-2, and ω-3) of fatty acids. Our studies show that BAMF0695 has a broad temperature optimum (over 70 % of maximal enzymatic activity retained between 20 to 50 °C) and is highly thermostable (T50 >50 °C), affording excellent adaptive compatibility for bioprocesses. We further demonstrate that BAMF0695 can utilize renewable microalgae lipid as a substrate feedstock for HFA production. Moreover, through extensive site-directed and site-saturation mutagenesis, we isolated variants with high regioselectivity, a rare property for CYPs that usually generate complex regioisomer mixtures. BAMF0695 mutants were able to generate a single HFA regiosiomer (ω-1 or ω-2) with selectivities from 75 % up to 91 %, using C12 to C18 fatty acids. Overall, our results demonstrate the potential of a recent CYP and its variants for sustainable and green production of high-value HFAs.
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Bacillus amyloliquefaciens , Bacillus amyloliquefaciens/metabolismo , Ácidos Grasos/química , Sistema Enzimático del Citocromo P-450/metabolismo , Hidroxilación , Especificidad por SustratoRESUMEN
Liquid side-streams from food industries can be processed and used in food applications and contribute to reduce the environmental footprint of industries. The goal of this study was to evaluate the effectiveness and applicability of protein and phosphorus separation processes, namely microfiltration, ultrafiltration and flocculation, using protein-rich process waters with low (LS) and high (HS) salt content from the processing of salted cod (Gadus morhua). The application of different flocculants (chitosan lactate and Levasil RD442) were evaluated at different concentrations and maturation periods (0, 1 or 3 h). The results showed that different flocculation treatments resulted in different recoveries of the nutrients from LS and HS. Proteins in LS could be most efficiently recovered by using Levasil RD442 0.25% and no maturation period (51.4%), while phosphorus was most efficiently recovered when using Levasil RD442 1.23% and a maturation period of 1 h (34.7%). For HS, most of its protein was recovered using Levasil RD442 1.23% and a maturation period of 1 h (51.8%), while phosphorus was recovered the most using Levasil 1.23% and no maturation period (47.1%). The salt contents allowed interactions through intermolecular forces with Levasil RD442. The ultrafiltration method was effective on HS since it recovered higher percentages of nutrients in the retentate phase (57% of the protein and 46% of the phosphorus) compared to LS.
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Quitosano , Ultrafiltración , Animales , Ultrafiltración/métodos , Cloruro de Sodio , Fósforo , NutrientesRESUMEN
Currently, side-streams (e.g., head, backbone, tail, and intestines) generated in the fish processing industry often end up as low-value products for feed applications or even as waste. In order to upcycle such side-streams, they need to be preserved to avoid oxidative degradation of the lipids between the generation point and the valorization plant. In the cod filleting industry, three main solid side-streams: viscera, heads, and backbones, are obtained. Hence, this study aimed to identify the most efficient antioxidant for preserving the cod side-streams using a dipping-based strategy prior to pre-valorization storage at low temperatures (ice and frozen storage). The dipping solutions evaluated contained: (i) a lipophilic rosemary extract (0.05% and 0.2% in 0.9% NaCl), (ii) Duralox MANC (a mixture of rosemary extract, ascorbic acid, tocopherols, and citric acid; 2% in 0.9% NaCl), and (iii) NaCl (0.9%) w/w solution. One group was not dipped. No dipping and dipping in NaCl were included as controls. The results showed a positive effect of dipping with solutions containing antioxidants as measured by peroxide value (PV), TBA-reactive substances (TBARS), and sensory profiling, e.g., rancid odor. Moreover, the oxidative stability increased with decreased storage temperature. The cod side-streams were in general most efficiently preserved by Duralox MANC, followed by the lipophilic rosemary extract (0.2%), compared to no dipping and dipping in NaCl solution and the lower concentration of the lipophilic rosemary extract (0.05%). The efficiency of the antioxidant treatments was independent of the side-stream fraction and storage temperature. Thus, using antioxidant dipping combined with low temperature storage is an efficient preservation method for maintaining the quality of the lipids in cod solid side-streams during their pre-valorization storage.
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Antioxidantes , Solución Salina , Antioxidantes/farmacología , Temperatura , Cloruro de Sodio , Ríos , Lípidos , Estrés OxidativoRESUMEN
Emulsions are implemented in the fabrication of a wide array of foods and therefore are of great importance in food science. However, the application of emulsions in food production is restricted by two main obstacles, that is, physical and oxidative stability. The former has been comprehensively reviewed somewhere else, but our literature review indicated that there is a prominent ground for reviewing the latter across all kinds of emulsions. Therefore, the present study was formulated in order to review oxidation and oxidative stability in emulsions. In doing so, different measures to render oxidative stability to emulsions are reviewed after introducing lipid oxidation reactions and methods to measure lipid oxidation. These strategies are scrutinized in four main categories, namely storage conditions, emulsifiers, optimization of production methods, and antioxidants. Afterward, oxidation in all types of emulsions, including conventional ones (oil-in-water and water-in-oil) and uncommon emulsions in food production (oil-in-oil), is reviewed. Furthermore, the oxidation and oxidative stability of multiple emulsions, nanoemulsions, and Pickering emulsions are taken into account. Finally, oxidative processes across different parent and food emulsions were explained taking a comparative approach.
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Lípidos , Agua , Emulsiones , Oxidación-Reducción , Estrés OxidativoRESUMEN
Phlorotannins play a role in biological functions to protect the cells against UV and oxidative damage in brown algae. We hypothesized that these compounds can function as photo-protectors and antioxidants in skin care formulations. Two types of extracts (water (FV-WE) and 67% v/v ethanol (FV-EE)) from Fucus vesiculosus were obtained with a phlorotannin content between 7-14% in dry extract. Exposure to sun light during growth was included as a factor on the phlorotannin content but did not influence the phlorotannin content. However, green colored F. vesiculosus had lower total phenolic content (TPC) (FV-WE = 6.9 g GAE 100 g-1 dw, FV-EE = 7.8 g GAE 100 g-1 dw) compared to those with a yellow/brownish color (FV-WE = 10.4-13.7 g GAE 100 g-1 dw, FV-EE = 11.2-14.0 g GAE 100 g-1 dw). UVA and UVB photo protective capabilities of the extracts through different biological effective protection factors (BEPFs) were evaluated using in vitro methods; the Mansur method for sun protection factor (SPF) and calculation of effective solar absorption radiation (%ESAR) to determine SPF and UVA protection factor (UVA-PF) of the extract and in seaweed enriched lotion. The SPF was negligible, when evaluating FV-WE in lotion (10 and 20% w/w). Moreover, %ESAR of the FV-WE showed SPF and some UVA-PF, but not enough to give sufficient SPF in lotions (10% w/w). It was concluded that the concentration of UV protecting compounds in the extracts was too low to and that further fractionation and purification of phlorotannins is needed to increase the SPF.
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Cosmecéuticos , Fucus , Phaeophyceae , Antioxidantes/farmacología , Extractos Vegetales/farmacologíaRESUMEN
This study was aimed at investigating the effect of low polarity water (LPW) on the extraction of bioactive compounds from Fucus vesiculosus and to examine the influence of temperature on the extraction yield, total phenolic content, crude alginate, fucoidan content, and antioxidant activity. The extractions were performed at the temperature range of 120-200 °C with 10 °C increments, and the extraction yield increased linearly with the increasing extraction temperature, with the highest yields at 170-200 °C and with the maximum extraction yield (25.99 ± 2.22%) at 190 °C. The total phenolic content also increased with increasing temperature. The extracts showed a high antioxidant activity, measured with DPPH (2,2-Diphenyl-1-picrylhydrazyl) radicals scavenging and metal-chelating activities of 0.14 mg/mL and 1.39 mg/mL, respectively. The highest yield of alginate and crude fucoidan were found at 140 °C and 160 °C, respectively. The alginate and crude fucoidan contents of the extract were 2.13% and 22.3%, respectively. This study showed that the extraction of bioactive compounds from seaweed could be selectively maximized by controlling the polarity of an environmentally friendly solvent.
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Fucus , Algas Marinas , Alginatos , Antioxidantes/química , Fucus/química , Fenoles , Extractos Vegetales/química , Algas Marinas/química , TemperaturaRESUMEN
This study performed the extraction of gelatin from saithe (Pollachius virens) skin and compared it to commercial marine gelatin. As a first stage, we investigated the physicochemical and biochemical properties of the gelatin. SDS-PAGE analysis revealed the presence of α-chains, ß-chains, and other high-molecular-weight aggregates. DSC thermograms showed typical gelatin behavior, while the FTIR spectra were mainly situated in the amide band region (amide A, amide B, amide I, amide II, and amide III). In the second stage, we produced O/W emulsions and analyzed their physical and oxidative stability over 9 days. Oil droplets stabilized with the gelatins obtained from saithe fish skin had a size of ~500 nm and a ζ-potential ~+25 mV, which is comparable to oil droplets stabilized with commercial gelatin products. Moreover, the oxidative stability of the emulsions stabilized with gelatin from saithe fish skin showed promising results in terms of preventing the formation of some volatile compounds towards the end of the storage period compared to when using the commercial gelatins. This study indicates the potential application of fish skin gelatin in the fields of food and cosmetics, as well as suggesting that further investigations of their techno-functional properties.
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Gadiformes , Gelatina , Animales , Gelatina/química , Emulsiones/química , Alimentos Marinos , Estrés Oxidativo , Agua/químicaRESUMEN
Enzymatic conversion of fatty acids (FAs) by fatty acid hydratases (FAHs) presents a green and efficient route for high-value hydroxy fatty acid (HFA) production. However, limited diversity was achieved among HFAs, to date, with respect to chain length and hydroxy position. In this study, two highly similar FAHs from Lactobacillus acidophilus were compared: FA-HY2 has a narrow substrate scope and strict regioselectivity, whereas FA-HY1 utilizes longer chain substrates and hydrates various double-bond positions. It is revealed that three active-site residues play a remarkable role in directing substrate specificity and regioselectivity of hydration. If these residues on FA-HY2 are mutated to the corresponding ones in FA-HY1, a significant expansion of substrate scope and a distinct enhancement in hydration of double bonds towards the ω-end of FAs is observed. A three-residue mutant of FA-HY2 (TM-FA-HY2) displayed an impressive reversal of regioselectivity towards linoleic acid, shifting the ratio of the HFA regioisomers (10-OH/13-OH) from 99:1 to 12:88. Notable changes in regioselectivity were also observed for arachidonic acid and for C18 polyunsaturated fatty acid substrates. In addition, TM-FA-HY2 converted eicosapentaenoic acid into its 12-hydroxy product with high conversion at the preparative scale. Furthermore, it is demonstrated that microalgae are a source of diverse FAs for HFA production. This study paves the way for tailor-made FAH design to enable the production of diverse HFAs for various applications from the polymer industry to medical fields.
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Proteínas Bacterianas , Ácidos Grasos/metabolismo , Hidrolasas , Lactobacillus acidophilus/enzimología , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/química , Hidrolasas/biosíntesis , Hidrolasas/química , Cinética , Ingeniería de Proteínas , Especificidad por SustratoRESUMEN
We report on small-angle neutron scattering (SANS) investigations of separate phase domains in high fat (70%) oil-in-water emulsions emulsified with the combination of sodium caseinate (CAS) and phosphatidylcholine (PC). The emulsion as a whole was studied by contrast variation to identify scattering components dominated by individual emulsifiers. The emulsion was subsequently separated into the aqueous phase and the oil-rich droplet phase, which were characterized separately. Emulsions produced with 1.05% (w/w) CAS and PC fraction which varies between 1.75% (w/w) and 0.35% (w/w) provided droplets between 10 and 19 µm in surface weighted mean in 70% fish oil-in-water emulsions. At least two-third of the overall CAS is associated with the interface, while the rest remains with the aqueous phase. Six percent of PC formed a monolayer in the interface, while the rest of the PC remains in the droplet phase in the form of multilayers. When the separated components were resuspended, the resuspended emulsion showed similar characteristics compared to the original emulsion in terms of droplet size distribution and neutron scattering. Instead, CAS in the aqueous phase separated from the emulsion shows aggregation not present in the corresponding CAS-in-D2O system.
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Natural phenolic compounds are important classes of plant, microorganism, and algal secondary metabolites. They have well-documented beneficial biological activities. The marine environment is less explored than other environments but have huge potential for the discovery of new unique compounds with potential applications in, e.g., food, cosmetics, and pharmaceutical industries. To survive in a very harsh and challenging environment, marine organisms like several seaweed (macroalgae) species produce and accumulate several secondary metabolites, including marine phenolics in the cells. Traditionally, these compounds were extracted from their sample matrix using organic solvents. This conventional extraction method had several drawbacks such as a long extraction time, low extraction yield, co-extraction of other compounds, and usage of a huge volume of one or more organic solvents, which consequently results in environmental pollution. To mitigate these drawbacks, newly emerging technologies, such as enzyme-assisted extraction (EAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE) have received huge interest from researchers around the world. Therefore, in this review, the most recent and emerging technologies are discussed for the extraction of marine phenolic compounds of interest for their antioxidant and other bioactivity in, e.g., cosmetic and food industry. Moreover, the opportunities and the bottleneck for upscaling of these technologies are also presented.
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Organismos Acuáticos/metabolismo , Fenoles/aislamiento & purificación , Solventes/química , Fraccionamiento Químico , Cromatografía con Fluido Supercrítico , Difusión de Innovaciones , Enzimas/química , Microondas , Metabolismo Secundario , Solventes/efectos adversos , Ondas UltrasónicasRESUMEN
Protein hydrolysates show great promise as bioactive food and feed ingredients and for valorization of side-streams from e.g., the fish processing industry. We present a novel approach for hydrolysate characterization that utilizes proteomics data for calculation of weighted mean peptide properties (length, molecular weight, and charge) and peptide-level abundance estimation. Using a novel bioinformatic approach for subsequent prediction of biofunctional properties of identified peptides, we are able to provide an unprecedented, in-depth characterization. The study further characterizes bulk emulsifying, foaming, and in vitro antioxidative properties of enzymatic hydrolysates derived from cod frame by application of Alcalase and Neutrase, individually and sequentially, as well as the influence of heat pre-treatment. All hydrolysates displayed comparable or higher emulsifying activity and stability than sodium caseinate. Heat-treatment significantly increased stability but showed a negative effect on the activity and degree of hydrolysis. Lower degrees of hydrolysis resulted in significantly higher chelating activity, while the opposite was observed for radical scavenging activity. Combining peptide abundance with bioinformatic prediction, we identified several peptides that are likely linked to the observed differences in bulk emulsifying properties. The study highlights the prospects of applying proteomics and bioinformatics for hydrolysate characterization and in food protein science.
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Antioxidantes/farmacología , Quelantes/farmacología , Biología Computacional , Emulsionantes/farmacología , Proteínas de Peces/farmacología , Gadiformes/metabolismo , Fragmentos de Péptidos/farmacología , Proteoma , Proteómica , Animales , Antioxidantes/metabolismo , Quelantes/metabolismo , Emulsionantes/metabolismo , Proteínas de Peces/metabolismo , Metaloendopeptidasas/metabolismo , Fragmentos de Péptidos/metabolismo , Estabilidad Proteica , Proteolisis , Subtilisinas/metabolismoRESUMEN
BACKGROUND: Ideas of patient involvement are related to notions of self-determination and autonomy, which are not always in alignment with complex interactions and communication in clinical practice. AIM: To illuminate and discuss patient involvement in routine clinical care situations in nursing practice from an ethical perspective. METHOD: A case study based on an anthropological field study among patients with advanced cancer in Denmark. ETHICAL CONSIDERATIONS: Followed the principles of the Helsinki Declaration. FINDINGS: Two cases illustrated situations where nurses refused patient involvement in their own case. DISCUSSION: Focus on two ethical issues, namely 'including patients' experiences in palliative nursing care' and 'relational distribution of power and knowledge', inspired primarily by Hannah Arendt's concept of thoughtlessness and a Foucauldian perspective on the medical clinic and power. The article discusses how patients' palliative care needs and preferences, knowledge and statements become part of the less significant background of nursing practice, when nurses have a predefined agenda for acting with and involvement of patients. Both structurally conditioned 'thoughtlessness' of the nurses and distribution of power and knowledge between patients and nurses condition nurses to set the agenda and assess when and at what level it is relevant to take up patients' invitations to involve them in their own case. CONCLUSION: The medical and institutional logic of the healthcare service sets the framework for the exchange between professional and patient, which has an embedded risk that 'thoughtlessness' appears among nurses. The consequences of neglecting the spontaneous nature of human action and refusing the invitations of the patients to be involved in their life situation call for ethical and practical reflection among nurses. The conditions for interaction with humans as unpredictable and variable challenge nurses' ways of being ethically attentive to ensure that patients receive good palliative care, despite the structurally conditioned logic of healthcare.
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Double-headed nucleotide monomers are capable of condensing the genetic information of DNA. Herein, a double-headed nucleotide with two cytosine bases (CC) is constructed. The additional cytosine is connected through a methylene linker to the 2'-position of arabinocytidine. The nucleotide is incorporated into oligonucleotides and its effect on duplex stability is studied. For single incorporations, a thermal stabilization of 4.0⯰C is found as compared to the unmodified duplex and it is shown that both nucleobases of CC participate in Watson-Crick base pairing. In combination with the previously published UT monomer, it is also shown that multiple incorporations are tolerated. For instance, a 16-mer sequence is targeted by a 13-mer oligonucleotide by using one CC and two UT monomers without compromising the overall duplex stability. Finally, the potential of double-headed nucleotides in triplex-forming oligonucleotides is studied, however, with the conclusion that the present design is not well-suited for this function.
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Citosina/química , ADN/química , Nucleótidos/química , Emparejamiento Base , Modelos Moleculares , Conformación de Ácido NucleicoRESUMEN
OBJECTIVE: The purpose of this study was to identify an effective lipid oxidation initiator which could predict, within 1 month, the long-term oxidative stability of a prototype skincare formulation. The main purpose was to find a potential initiator not to assess oxidation stability of the formulations. METHODS: Four initiators (below) were examined in three steps: Reaction kinetics using a Clark electrode (Oxygraph); Effect of adding an initiator on the product's physical and oxidative stability in prototype skincare formulations by visual observation, peroxide value and headspace GC-MS determination of volatile oxidation products; and Ability to differentiate unstable vs. stable prototype creams by initiator addition. The four initiators explored were: FeCl2 /H2 O2 , FeCl3 /ascorbic acid, 2,2'-Azobis(2,4-dimethylvaleronitrile) (AMVN) and 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH) RESULTS: In Oxygraph, the initiator systems FeCl2 /H2 O2 and FeCl3 /ascorbic acid were good accelerators of oxygen consumption. The addition of FeCl2 /H2 O2 to prototype formulations did not affect the physical stability. However, the addition of FeCl3 /ascorbic acid to prototype formulations resulted in phase separation and FeCl3 /ascorbic acid was therefore deemed unusable. Moreover, the addition of AAPH or AMVN resulted in an increased and decreased viscosity respectively. In the oxidation stability study, peroxide value increased significantly when AMVN was added. However, the peroxide value remained low for the other initiators and the control (no initiator). The secondary volatile oxidation product, butanal, increased most with the FeCl2 /H2 O2 addition. Three out of the four initiators did not have the ability to rank the stable and unstable formulations in accordance with the result obtained for volatile oxidation products after 42 days of storage at 20°C of formulations without initiator. Only, FeCl2 /H2 O2 was able to rank the formulations in accordance with the oxidative stability observed for volatile oxidation products after 42 days of storage. CONCLUSION: FeCl2 /H2 O2 showed potential as an initiator to predict the oxidative stability of skincare formulations, but more studies are needed to confirm the result in a broader range of products over a longer time.
OBJECTIF: Le but de cette étude était d'identifier un initiateur efficace de l'oxydation des lipides qui pourrait prédire, dans un délai d'1 mois, la stabilité oxydative à long terme d'une formulation prototype de soins pour la peau. Le principal objectif était de trouver un initiateur potentiel et non pas d'évaluer la stabilité à l'oxydation des formulations. MÉTHODES: Quatre initiateurs (ci-dessous) ont été évalués au cours de trois étapes: Cinétique de réaction à l'aide d'une électrode de Clark (Oxygraphe); Effet de l'addition d'un initiateur sur la stabilité physique et oxydative du produit dans des prototypes de formulations par observation visuelle de l'indice de peroxyde et détermination des produits d'oxydation volatiles par GC-MS - espace de tête; et Capacité à différencier les prototypes de crèmes instables des prototypes de crèmes stables par addition d'un initiateur. Les quatre initiateurs étudiés étaient : FeCl2 /H2 O2 , FeCl3 /acide ascorbique, 2,2'-azobis (2,4-diméthylvaléronitrile) (AMVN) et 2,2'-azobis (2-méthylpropionamidine), dichlorhydrate (AAPH) RÉSULTATS: Dans l'oxygraphe, les systèmes initiateurs FeCl2 /H2 O2 et FeCl3 /acide ascorbique étaient de bons accélérateurs de la consommation en oxygène. L'addition de FeCl2 /H2 O2 aux prototypes de formulations n'a pas eu d'impact sur la stabilité physique. Cependant, l'addition de FeCl3 /acide ascorbique aux prototypes de formulations a entraîné une séparation des phases et le système FeCl3 /acide ascorbique a donc été jugé inutilisable. De plus, l'addition d'AAPH ou d'AMVN a entraîné une augmentation et une diminution de la viscosité, respectivement. Dans l'étude de stabilité oxydative, l'indice de peroxyde a significativement augmenté lorsque l'AMVN a été ajouté. Cependant, l'indice de peroxyde est resté faible pour les autres initiateurs et le témoin (sans initiateur). L'augmentation la plus importante du produit d'oxydation volatile secondaire, le butanal, a été observée avec l'addition de FeCl2 /H2 O2 . Trois des quatre initiateurs n'ont pas permis de classer les formulations stables et instables d'après le résultat obtenu pour les produits d'oxydation volatiles après 42 jours de conservation à 20 °C des formulations sans initiateur. Seul FeCl2 /H2 O2 a été en mesure de classer les formulations conformément à la stabilité oxydative observée pour les produits d'oxydation volatiles après 42 jours de conservation. CONCLUSION: FeCl2 /H2 O2 a montré un potentiel comme initiateur pour prédire la stabilité oxydative de formulations de soins pour la peau, mais des études supplémentaires sont nécessaires pour confirmer le résultat sur une plus large gamme de produits et sur une plus longue période.
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Lípidos/química , Crema para la Piel/química , Cromatografía de Gases y Espectrometría de Masas , Cinética , Oxidantes/química , Oxidación-ReducciónRESUMEN
Production of peptides with various effects from proteins of different sources continues to receive academic attention. Researchers of different disciplines are putting increasing efforts to produce bioactive and functional peptides from different sources such as plants, animals, and food industry by-products. The aim of this review is to introduce production methods of hydrolysates and peptides and provide a comprehensive overview of their bioactivity in terms of their effects on immune, cardiovascular, nervous, and gastrointestinal systems. Moreover, functional and antioxidant properties of hydrolysates and isolated peptides are reviewed. Finally, industrial and commercial applications of bioactive peptides including their use in nutrition and production of pharmaceuticals and nutraceuticals are discussed.
Asunto(s)
Proteínas en la Dieta , Tecnología de Alimentos , Péptidos/fisiología , Secuencia de Aminoácidos , Alimentación Animal , Animales , Sistema Cardiovascular/efectos de los fármacos , Proteínas en la Dieta/metabolismo , Fermentación , Alimentos , Tecnología de Alimentos/métodos , Alimentos Funcionales , Tracto Gastrointestinal/efectos de los fármacos , Cementos de Ionómero Vítreo/metabolismo , Humanos , Inmunidad/efectos de los fármacos , Sistema Nervioso/efectos de los fármacos , Péptidos/química , Péptidos/farmacología , Hidrolisados de Proteína , GustoRESUMEN
BACKGROUND: Common carp roe is a rich protein and oil source, which is usually discarded with no specific use. The aims of this study were to extract oil from the discarded roe and examine functional, antioxidant, and antibacterial properties of defatted roe hydrolysates (CDRHs) at various degrees of hydrolysis (DH). RESULTS: Gas chromatography of fatty acid methyl esters revealed that common carp roe oil contained high levels of unsaturated fatty acids. The results of high-performance liquid chromatography-mass spectrometry indicated that enzymatic hydrolysis of defatted roe yielded higher content of essential amino acids. CDRHs displayed higher solubility than untreated defatted roe, which increased with DH. Better emulsifying and foaming properties were observed at lower DH and non-isoelectric points. Furthermore, water and oil binding capacity decreased with DH. CDRHs exhibited antioxidant activity both in vitro and in 5% roe oil-in-water emulsions and inhibited the growth of certain bacterial strains. CONCLUSION: Common carp roe could be a promising source of unsaturated fatty acids and functional bioactive agents. Unsaturated fatty acid-rich oil extracted from common carp roe can be delivered into food systems by roe oil-in-water emulsions fortified by functional, antioxidant, and antibacterial hydrolysates from the defatted roe. © 2017 Society of Chemical Industry.
Asunto(s)
Antibacterianos/análisis , Antioxidantes/análisis , Carpas , Huevos/análisis , Ácidos Grasos Insaturados/aislamiento & purificación , Aceites de Pescado/química , Aminoácidos/análisis , Animales , Suplementos Dietéticos , Emulsiones , Hidrólisis , SolubilidadRESUMEN
In the search for double-coding DNA-systems, three new pyrimidine nucleosides, each coded with an additional nucleobase anchored to the major groove face, are synthesized. Two of these building blocks carry a thymine at the 5-position of 2'-deoxyuridine through a methylene linker and a triazolomethylene linker, respectively. The third building block carries an adenine at the 6-position of pyrrolo-2'-deoxycytidine through a methylene linker. These double-headed nucleosides are introduced into oligonucleotides and their effects on the thermal stabilities of duplexes are studied. All studied double-headed nucleotide monomers reduce the thermal stability of the modified duplexes, which is partially compensated by using consecutive incorporations of the modified monomers or by flanking the new double-headed analogs with members of our former series containing propyne linkers. Also their potential in triplex-forming oligonucleotides is studied for two of the new double-headed nucleotides as well as the series of analogs with propyne linkers. The most stable triplexes are obtained with single incorporations of additional pyrimidine nucleobases connected via the propyne linker.