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The tenacious biofilms formed by Streptococcus mutans are resistant to conventional antibiotics and current treatments. There is a growing need for novel therapeutics that selectively inhibit S. mutans biofilms while preserving the normal oral microenvironment. Previous studies have shown that increased levels of cyclic di-AMP, an important secondary messenger synthesized by diadenylate cyclase (DAC), favored biofilm formation in S. mutans. Thus, targeting S. mutans DAC is a novel strategy to inhibit S. mutans biofilms. We screened a small NCI library of natural products using a fluorescence detection assay. (+)-Brazilin, a tetracyclic homoisoflavanoid found in the heartwood of Caesalpinia sappan, was identified as one of the 11 "hits," with the greatest reduction (>99%) in fluorescence at 100 µM. The smDAC inhibitory profiles of the 11 "hits" established by a quantitative high-performance liquid chromatography assay revealed that (+)-brazilin had the most enzymatic inhibitory activity (87% at 100 µM) and was further studied to determine its half maximal inhibitory concentration (IC50 = 25.1 ± 0.98 µM). (+)-Brazilin non-competitively inhibits smDAC's enzymatic activity (Ki = 140.0 ± 27.13 µM), as determined by a steady-state Michaelis-Menten kinetics assay. In addition, (+)-brazilin's binding profile with smDAC (Kd = 11.87 µM) was illustrated by a tyrosine intrinsic fluorescence quenching assay. Furthermore, at low micromolar concentrations, (+)-brazilin selectively inhibited the biofilm of S. mutans (IC50 = 21.0 ± 0.60 µM) and other oral bacteria. S. mutans biofilms were inhibited by a factor of 105 in colony-forming units when treated with 50 µM (+)-brazilin. In addition, a significant dose-dependent reduction in extracellular DNA and glucan levels was evident by fluorescence microscopy imaging of S. mutans biofilms exposed to different concentrations of (+)-brazilin. Furthermore, colonization of S. mutans on a representative model of enamel using suspended hydroxyapatite discs showed a >90% reduction with 50 µM (+)-brazilin. In summary, we have identified a drug-like natural product inhibitor of S. mutans biofilm that not only binds to smDAC but can also inhibit the function of smDAC. (+)-Brazilin could be a good candidate for further development as a potent therapeutic for the prevention and treatment of dental caries.IMPORTANCEThis study represents a significant advancement in our understanding of potential therapeutic options for combating cariogenic biofilms produced by Streptococcus mutans. The research delves into the use of (+)-brazilin, a natural product, as a potent inhibitor of Streptococcus mutans' diadenylate cyclase (smDAC), an enzyme crucial in the formation of biofilms. The study establishes (+)-brazilin as a non-competitive inhibitor of smDAC while providing initial insights into its binding mechanism. What makes this finding even more promising is that (+)-brazilin does not limit its inhibitory effects to S. mutans alone. Instead, it demonstrates efficacy in hindering biofilms in other oral bacteria as well. The broader spectrum of anti-biofilm activity suggests that (+)-brazilin could potentially serve as a versatile tool in a natural product-based treatment for combating a range of conditions caused by resilient biofilms.

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Iron deficiency is one of the main causes of anemia in the world, especially in children and women, so food fortification through microencapsulation is a viable alternative to combat this deficiency. The present work aimed to encapsulate iron in a water-in-oil-in-water double emulsion (W1/O/W2), which was formed with whey protein isolate and polyglycerol polyricinoleate as the emulsifying agents, tara gum as a thickening agent, and sucrose as an osmotic active substance. The double emulsion formed with 12% whey protein isolate, 0.8% tara gum, and 2% sucrose presented high encapsulation efficiency (96.95 ± 1.00%) and good stability (up to 7 days). Additionally, after the in vitro gastrointestinal simulations, the bioaccessibility was high for adults (49.54 ± 5.50%) and infants (39.71 ± 2.33%). Finally, the study show that double emulsions can form stable systems with high iron bioaccessibility even in infant gastric systems, which indicates the possibility of using double emulsions to fortify food with iron.

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Objective: To evaluate orthodontists' preferences in the use and timing of appliances for the correction of Class II and Class III malocclusions in growing patients and the sociodemographic factors that influence these preferences. Material and Methods: Active members of the Colombian Orthodontics Society (SCO) were invited to complete a previously validated survey on the use of Class II and Class III correctors in growing patients. Results: 180 orthodontists responded (80 male, 100 female). The appliances used most frequently in the treatment of Class II malocclusion were Planas indirect tracks (32.78%) and Twin-blocks (30.56%). Facemasks (62.22%) and Progenie plates (25%) were the most prevalent appliances used in the treatment of Class III malocclusions. Regarding treatment timing, 52% of the orthodontists stated that Class II malocclusions must be treated during late mixed dentition or early permanent dentition, 42% stated that treatment for Class III malocclusions should occur during early mixed dentition. Appliance use and treatment timing were significantly associated with sex (p= 0.034), years of practice (p= 0.025), and area of work (private clinics or public institutions), (p= 0.039). Conclusion: Twin-blocks and Facemask appliances were the preferred appliances for Class II and Class III treatment, respectively, in growing patients. Most of the orthodontists believed that Class II malocclusions must be treated during late mixed dentition and that Class III malocclusions must be treated during early mixed dentition. Sociodemographic variables are related factors that influence orthodontists' preferences in the use of these appliances.

Objetivo: Evaluar las preferencias de los ortodoncistas en el uso y momento oportuno de uso de aparatología para la corrección de maloclusiones Clase II y Clase III en pacientes en crecimiento y los factores sociodemográficos que influyen en estas preferencias. Material y Métodos: Se invitó a miembros activos de la Sociedad Colombiana de Ortodoncia (SCO) a completar una encuesta previamente validada, sobre el uso de correctores para Clase II y Clase III en pacientes en crecimiento. Resultados: Respondieron un total de 180 ortodoncistas (80 hombres, 100 mujeres). La aparatología más utilizada en el tratamiento de las maloclusiones de Clase II fueron pistas indirectas de Planas (32,78%) y bloques gemelos (30,56%). La máscara facial (62,22%) y las placas progenie (25%) fueron los aparatos más utilizados en el tratamiento de las maloclusiones de Clase III. En cuanto al momento oportuno del tratamiento, el 52% de los ortodoncistas afirmó que las maloclusiones de Clase II deben tratarse durante la dentición mixta tardía o la dentición permanente temprana, el 42% afirmó que el tratamiento para las maloclusiones de Clase III debe ocurrir durante la dentición mixta temprana. El uso de aparatos y el momento oportuno del tratamiento se asociaron significativamente con el sexo (p= 0,034), los años de práctica (p= 0,025) y el área de trabajo (clínicas privadas o instituciones públicas) (p= 0,039). Conclusión: Los aparatos bloques gemelos y la máscara facial fueron los preferidos para el tratamiento de Clase II y Clase III, respectivamente, en pacientes en crecimiento. La mayoría de los ortodoncistas consideran que las maloclusiones de Clase II deben tratarse durante la dentición mixta tardía y que las maloclusiones de Clase III deben tratarse durante la dentición mixta temprana. Las variables sociodemográficas son factores relacionados que influyen en las preferencias de los ortodoncistas en el uso de estos aparatos.

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BACKGROUND: Tara gum (TG) is characterized by its high viscosity and medium solubility, which is a result of its high molecular mass. However, for many applications, these characteristics are undesirable, making the use of TG infeasible. The present study aimed to evaluate the effect of high-intensity ultrasound on the depolymerization of aqueous solutions of TG. The effect of ultrasonication was investigated by viscometry analysis as well as Fourier transform infrared spectroscopy (FTIR) and solubility. RESULTS: The intrinsic viscosity (η) and the molecular weight (Mw ) of TG decreased after ultrasound, achieving a molecular weight reduction of 13.50 × 105 g mol-1 after 60 min of sonication at 25 °C compared to 22.04 × 105 g mol-1 before treatment. Degradation kinetics were applied to estimate the rate constant of degradation (k). It was found that the k value of TG increased with increasing temperature from 25 to 55 °C. Partially hydrolyzed TG showed greater solubility at the two temperatures investigated (25 and 80 °C). Ultrasonic treatment did not change the chemical structure of the TG molecules according to the structural analysis by FTIR, confirming its action only as breaking the structure of the polymer. CONCLUSION: Ultrasound is a simple method for effectively reducing the molecular weight and viscosity and increasing the solubility of TG without using chemical reagents. The synthesis of partially hydrolyzed TG expands its potential for use in food products, including as a soluble dietary fiber. © 2022 Society of Chemical Industry.

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Pseudocereals (amaranth, buckwheat and quinoa) are emerging as popular gluten-free crops. This may be attributed to their wide-ranging health benefits, including antioxidant, hypoglycemic and serum-cholesterol reducing properties. Proteins of these crops have a high nutritional quality as a result of the presence of essential amino acids. Additionally, amaranth, buckwheat and quinoa proteins (AP, BP and QP, respectively) have physicochemical properties that are useful for the manufacture of different types of food. However, native pseudocereal proteins demonstrate a low solubility in water, mainly because of their composition. The major components of these proteins are albumins (water-soluble) and globulins (salt-soluble), although some proportions of glutelin (alkali-soluble) and prolamins (alcohol-soluble) are also found. The most commonly used method for extracting pseudocereal proteins is the alkaline extraction method, which may contribute to the low solubility of pseudocereal protein. Fortunately, different methods for modifying physicochemical (or techno-functional) properties have been proposed to extend their industrial application. For example, high-intensity ultrasound (HIUS) proved useful for improving the solubility of API and QP. Heating can allow for the formation of soluble aggregates of QP. The combination of heating and HIUS can improve the digestibility, solubility and foam properties of AP. Conjugation through the Maillard reaction can improve BPI and QP interfacial properties. Thus, present study provides a review of the solubility, extraction and modification of the techno-functional properties of AP, BP and QP. © 2022 Society of Chemical Industry.

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Cattle of Colombian creole breed Chino Santandereano in the raising phase were subjected to stabling for 100 days in order to determine the productive, nutritional, and metabolic capacity when exposed to different degrees of protein-energy supplementation. Sixteen whole males with an initial mean weight of 377.69 ± 16.55 kg were used in completely randomized delineation with four treatments and four repetitions per treatment, as follows: UNS, not supplemented; low, supplemented with amounts relative to 0.5% of body weight; medium, supplemented with amounts relative to 1.0% of the live weight; and high, supplemented with amounts relative to 1.5% of body weight. At the end of each experimental period, the animals were weighed, and samples of feed, feces, blood, and urine were collected to determine the performance, consumption, and digestibility of the nutritional components, and nitrogen balance. In the greater performance, consumption, and digestibility of DM, OM, C-NFCP, EE, and NFC, the concentration of ureic nitrogen in blood and urine (P <0.05) was observed in supplemented animals when contrasted with UNS. Bovine Chinese Santandereano presents high productive, nutritional, and metabolic potential as a response to high levels of protein-energy supplementation.

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Vitamin D3 plays a fundamental role in human health; however, it is highly susceptible to environmental conditions and the gastrointestinal tract. In this study, complex coacervates obtained from gelatin A and carboxymethyl tara gum (CMTG) were used as wall materials for the encapsulation of vitamin D3 (VD3). Zeta potential and turbidity measurements were employed to optimize the pH and ratio (gelatin A:CMTG), and the results showed that the ideal conditions for the complex coacervation were pH 4.0 and a 6:1 ratio. The encapsulation efficiency (EE) was determined as a function of the total concentration of biopolymers (TC%) and the core-to-wall ratio, and the greatest EE (80%) was achieved at a TC of 1% and a ratio of 1:2; spherical particles with an average size of 0.25 µm were obtained. The microencapsulation increased the thermal stability of VD3, and FTIR confirmed the presence of the biopolymers and VD3 in the capsules. An in vitro simulation showed a more pronounced release in the small intestine with a vitamin bioaccessibility of 56%. The encapsulation of bioactive lipophilic compounds by complex coacervates of gelatin A and CMTG resulted in improved stability and prolonged release during digestion.

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RESUMEN El mercado campesino de Coopmercasan inició su funcionamiento en 2011 brindando productos agrícolas frescos e inocuos al municipio de Florencia, departamento del Caquetá. En ocho años de operación, han tenido aciertos y desaciertos, también han recibido el apoyo de diferentes instituciones, sin embargo, a la fecha se desconoce sus realidades actuales y los retos y desafíos que han venido cambiando a lo largo del tiempo. Por lo anterior, esta investigación buscó construir las dinámicas de esta experiencia a través de la autorreflexión, la información base para la toma de decisiones y la orientación de sus acciones de mejora. El trabajo se realizó en el municipio de Florencia, las herramientas para el levantamiento de la información empleadas fueron encuestas, entrevistas y observación participante. Dentro de los principales hallazgos se tiene que, si bien el mercado ha logrado posicionarse con una base interesante de clientes, su oferta no está cumpliendo las expectativas respecto de los volúmenes y la diversidad de demandada de los clientes, y aunque la gran mayoría de los apoyos entregados por las instituciones han sido dirigidos a procesos de fortalecimiento organizativos, sigue siendo el aspecto más débil.

ABSTRACT The COOPMERCASAN peasant market began its operation in 2011, providing fresh and safe agricultural products to the population of Florence. In these eight years of operation, they have had successes and failures, they have also received the support of different institutions, however, to date, their current realities are unknown, as well as the challenges, which have been changing over time. It is because of the above that this research sought to build the dynamics of this experience through self-reflection, base information for decision-making, and the orientation of their improvement actions. The work was carried out in the municipality of Florence, the tools for gathering the information were surveys, interviews, and participant observation. Among the main findings, it was discovered that, although the market has managed to position itself with an interesting customer base, its offer is not meeting expectations in terms of the volumes and diversity demanded by customers and that, although the vast majority of the support provided by the institutions has been directed towards organizational strengthening processes, it continues to be the weakest aspect.

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RESUMEN Objetivo. Cuantificar la concentración y consumo de los fragmentos de la proteína (NNP, PV, PVAD, PVLD, PIDN y PIDA) presente en la dieta suministrada a bovinos y su efecto en la digestibilidad de la proteína bruta. Materiales y métodos. Fueron analizadas dietas ofrecidas a bovinos Chino Santandereano en estabulación, recibiendo diferentes niveles de suplementación, utilizando cuatro animales en delineamiento en cuadrado latino 4x4, siendo los tratamientos: NS, no suplementados; BAJO, suplementados con cantidad relativa al 0.5% del peso corporal; MEDIO, suplementados con cantidad relativa al 1.0% del peso corporal; ALTO, suplementados con cantidad relativa al 1.5% del peso corporal. El consumo fue determinado diariamente y la digestibilidad a través de colecta total de heces en los dos últimos días de cada periodo. Resultados. Mayor concentración de proteína bruta fue encontrada en suplemento en comparación con el pasto (p<0.001), exhibiendo el forraje mayor concentración de PBNNP (p<0.001), a la vez que el suplemento presentó concentración más elevada de PV (p<0.001) y PVAD (p=0.027). Animales suplementados presentaron mayor consumo de PB, PBNNP (p=0.037), PV, PIDN, PVAD, PIDA y PVLD (p<0.05), no obstante, cuando se determinó la concentración que representa el consumo de PIDA en el consumo de PB, no se observó diferencia entre suplementados y NS (p=0.078). Mayor digestibilidad de la PB fue encontrada en animales suplementados cuando contrastados con NS (p<0.001), observándose entre tratamientos suplementados un efecto lineal ascendente a medida que aumentó el nivel de suplementación. Conclusiones. La suplementación mejora la digestibilidad de la proteína bruta por aportar mayor cantidad de fragmentos nitrogenados de alta digestibilidad.

ABSTRACT Objective. To quantify the concentration and consumption of the protein fragments (NPN, TP, RDTP, SDTP, NDIP, and ADIP) present in the diet supplied to cattle, and its effect on the digestibility of crude protein. Materials and methods. Diets offered to Chino Santandereano cattle in stables were analyzed, receiving different levels of supplementation, using four animals in the 4x4 Latin square outline, the treatments being: NS, not supplemented; LOW, supplemented with an amount relative to 0.5% of body weight; MEDIUM, supplemented with an amount relative to 1.0% of body weight; HIGH, supplemented with a quantity relative to 1.5% of body weight. Consumption was determined daily, and digestibility through total stool collection in the last two days of each period. Results. A higher concentration of crude protein was found in supplement compared to grass (p<0.001), the forage exhibiting a higher concentration of CPNPN (p<0.001), at the same time, that the supplement presented higher concentration of TP (p<0.001) and RDTP (p=0.027). Supplemented animals presented higher consumption of CP, CPNPN (p=0.037), TP, NDIP, RDTP, ADIP and SDTP (p<0.05), however, when the concentration that represents the consumption of ADIP in the consumption of CP was determined, no difference was observed between supplemented and NS (p=0.078). Higher digestibility of CP was found in supplemented animals when contrasted with NS (p<0.001), an upward linear effect was observed between supplemented treatments as the level of supplementation increased. Conclusions. Supplementation improves the digestibility of crude protein by providing a greater amount of highly digestible nitrogenous fragments.

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This study evaluated the most appropriate conditions (pH and biopolymers ratio) for the formation of the complex between ß-lactoglobulin (ß-lg) and sodium alginate (NaAlg). Furthermore, we microencapsulated black pepper essential oil (EO) using these biopolymers and transglutaminase as a cross-linking agent, and stability during in vitro digestion and its release in food models were studied. A ratio of 17:1 (ß-lg/NaAlg) at a pH of 4.5 was the optimal condition for the formation of the complex. The encapsulation efficiency (85.01% ± 0.26) and chemical and morphological characteristics suggested that black pepper EO was microencapsulated using polymers and cross-linking agent naturals. The particle size demonstrated that the capsules produced were on micro scale. The black pepper EO microcapsules lost lower release in water, and the Rigger-Peppas model indicated that the Fickian diffusion mechanism occurred. The microcapsules demonstrated a low release of black pepper EO during oral and gastric digestion and a higher release in intestinal digestion. The black pepper EO after digestion presented high stability (84.8% ± 0.07), and bioaccessibility (31.16% ± 0.3). The results suggest that the black pepper EO was microencapsulated and, preserved in aqueous food model and during oral and gastric conditions tested in vitro.

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Black pepper essential oil (EO) was encapsulated by complex coacervation with lactoferrin and sodium alginate using transglutaminase as a cross-linking agent. The encapsulation efficiency varied from 31.66 to 84.48%. Chemical and morphological characteristics suggest that the EO was encapsulated in a lactoferrin/sodium alginate shell. The chemical composition of the encapsulated EO was identified by gas chromatography (GC) and nuclear magnetic resonance (NMR). The GC and NMR analyses indicated good core protection with the materials used. The stability of the black pepper EO capsules under in vitro digestion was evaluated. Theses capsules demonstrated the low release of the EO during gastric digestion and higher release in intestinal digestion. These results suggest that these capsules can be used to transport active ingredients and that they are resistant to oral and gastric conditions that were tested in vitro.

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In this study, sacha inchi oil (SIO) (Plukenetia volubilis L.) was microencapsulated via complex coacervation of ovalbumin (OVA) and sodium alginate (AL), and the microcapsule properties were characterized. The omega-3 content in the SIO was evaluated after in vitro gastric simulation and microencapsulation. The coacervate complex between OVA and AL was evaluated based on electrostatic interactions and developed for use as a wall material via the SIO microencapsulation process. The best mass ratio for the biopolymers (OVA:AL) was 4:1 at pH 3.8, and the complex exhibited a thermal resistance at 189.86 °C. The SIO microcapsules showed a high encapsulation efficiency of approximately 94.12% in the ratio (OVA:AL) of 1:1. Furthermore, microencapsulated SIO presented resistance under gastric conditions with a low release of acyl (ω-3) units. These results demonstrate that it is possible to use OVA:AL as encapsulating agents to protect bioactive compounds and to improve the thermal behavior of microcapsules.

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Carboxymethyl tara gum (CMTG) was synthesized from the reaction between tara gum (TG) and monochloroacetic acid (MCA) in the presence of sodium hydroxide. The modification reaction was optimized in terms of the MCA/NaOH ratio, reaction time and temperature evaluated for degree of substitution (DS). The etherification was confirmed by FTIR and 13C NMR spectroscopy, and it was characterized by different analyses. After carboxymethylation, CMTG showed new bonds at 1592, 1413 and 1320 cm-1 by FTIR and a new peak at δ = 178 ppm by 13C NMR in response to the insertion of the carbonyl group. The microscopy showed higher degradation on the surface of the CMTG particles, and XRD indicated low crystallinity of the CMTG. Static light scattering demonstrated a reduction in the molar mass of tara gum after carboxymethylation. Thermal analysis (TGA and DSC) revealed a lower thermal stability of carboxymethylated gum compared to that of unmodified gum. Despite the insertion of negative charges demonstrated by the potential-zeta, CMTG and TG presented pseudoplastic behavior according to the rheological analyses, and CMTG presented lower viscosity at the concentrations that were studied.

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Drills are an important element of disaster management, helping to increase preparedness and reduce the risk of real-time failure. Yet, they are not applied systematically to slow-onset disasters such as a drought, which causes damage that is not instantly apparent and thus does not solicit immediate action. This case study evaluates how drills inform institutional responses to slow-onset disasters. It spotlights Guatemala, a country where drought has severe impacts on livelihoods and the food security of small farmers. By implementing part of the Ministry of Agriculture, Livestock and Food's institutional response plan for drought, it explores how drills can help to detect issues in emergency response and to foster an institutional focus on improvements in preparedness. The results reveal that drills alone do not trigger institutional improvements if unsupported by a wider strategy that seeks to enhance capacities and protocols. These findings are valuable, however, in making problems transparent and in creating the space for discussion.

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The aim of this work was to studied the formation, stability and characterization of oil-in-water emulsions formed by Sacha Inchi oil (SIO) 8% (w/w) with either ovalbumin (Ova) or Tween 80 (Tw80), as emulsifiers at 0.5%-2.0% (w/w) and stabilized with pectin (Pec) at 1.0%-3.0% (w/w) or xanthan gum (XG) at 0.25%-1.0% (w/w). The emulsions were evaluated at 0, 1, 7 and 14 days after preparation and kept at a temperature of 25 ±â€¯1 °C for the ζ-potential, particle size distribution, polydispersion, and emulsion stability index measurements. The emulsions were characterized by optical microscopy, viscosity and rheological behavior. It was observed that it is possible to form oil-in-water emulsions with SIO-Ova and Pec that are stable at 25 °C for at least 14 days with a polydispersion value between 0.2 and 0.5. However, the emulsions with SIO-Ova and XG are stable at several concentrations of XG but are more viscous and can form aggregates. The presence of a biopolymer is essential for the kinetic stability of the emulsions containing Ova as the emulsifier. For the emulsions containing Tw80, this conclusion applies only to emulsions with XG concentrations of 0.5% to 1.0%, in which the stability mechanism is distinct.

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The aim of this study was to evaluate the influence of some parameters (pH, NaCl, and ratio of biopolymers) on the formation of the complex coacervates of lactoferrin and sodium alginate. Different ratios of lactoferrin:sodium alginate were tested (1:1, 1:2, 1:4,1:8, 2:1, 4:1, and 8:1) at pH levels ranging from 2.0 to 7.0 with different concentrations of NaCl (0, 50, 100, 150, and 200 mM). Sodium alginate has a molecular weight of 138 kDa ±â€¯0.07. The ratio of 8:1(lactoferrin: sodium alginate) at a pH of 4.0 with a low salt concentration was the optimal condition for the formation of the complex. The thermodynamic parameters demonstrated that the interaction between lactoferrin and sodium alginate was exothermic and spontaneous with a favorable enthalpic and unfavorable entropic contribution during the interaction. The chemical, thermal and morphological characteristics of the biopolymers and the complex coacervates demonstrated their nature and changes due to electrostatic interactions. The formation of complex coacervates between lactoferrrin and sodium alginate can serve as an alternative to the incorporation of lipophilic functional ingredients sensitive to high temperatures in various food systems.

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The complexation between lysozyme and pectin was studied by acidification using zeta potential, turbidity measurements and calorimetry titration. The complexes were analyzed in various NaCl concentrations with different ratios. At ratio 1:1 with 0.01M NaCl, is worth mentioning that the insoluble complexes were formed between pH 2.0 and 7.0, which represents a great range to apply this complex to different food matrices. When the ratio was increased from 1:1 to 3:1, the pH range between the pHφ1 and pHφ2 increased even more. When the NaCl concentration was increased from 0.01M to 0.2M, a progressive reduction of turbidity was observed. At 0.4M NaCl, there was total suppression of complex formation at ratio ≤ 3:1. The process of complex coacervate formation occurred in two different steps, presenting favorable enthalpic as well as entropic contributions. The positive entropy change is a strong indication that water molecules have been released from the complex surface, however the positive sign of TΔS suggests that hydrophobic interactions were involved in the interaction between lysozyme and pectin. Microscopy images of the samples revealed that the complexes presented a spheroid-like appearance which may contribute to possible future applications.

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Whey proteins are obtained from dairy industry waste. Studies involving the analysis of the bioactive compounds in whey show health benefits, as it is an excellent source of indispensable amino acids. Milk whey contains principally ß-lactoglobulin, α-lactoglobulin, bovine serum albumin, and lactoferrin, proteins with innumerable functional and technological properties. One application of these proteins in food is the formation of interpolymer complexes, along with other proteins or anionic polysaccharides. The formation of complexes occurs mainly through electrostatic interactions between a negatively charged biopolymer and a positively charged biopolymer. This formation is influenced by factors such as pH, ionic strength, and biopolymer ratio. Because they do not use high temperatures and chemical reagents and have additional nutritional and functional value, these complexes have been used as encapsulating agents for bioactive ingredients. Recent studies on their training and applications are addressed in this review to boost new research and applications in the food industry, thus increasing opportunities for utilizing whey proteins.

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The formation of heteroprotein coacervates obtained by the interaction of ovalbumin (Ova) and lysozyme (Lys) was investigated using turbidimetric analysis and the zeta potential at different protein ratios, pH values and concentrations of NaCl. The complexes were formed over a wide pH range with a 1:1 (Ova:Lys) ratio and the highest turbidity was observed at pH 7.5, which optimal biopolymer interactions occurring. The addition of NaCl disfavored formation, even at low concentrations, and suppressed it at 300mM. The complex coacervate formation occurred in the region between the isoelectric points (pI) of the proteins, predominantly by electrostatic interactions but with participation of hydrogen bonds. The structures formed had an average size of ∼2µm, which was well above the isolated proteins, and microscopic analysis revealed that the complexes had a globular structure. The interaction was exothermic and spontaneous with a favorable entropic and unfavorable entropic contribution during interaction.

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