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Research background. Amaranth (Amaranthus hypochondriacus) flour produces films with excellent barrier properties against water vapor, allowing food preservation, but the mechanical properties are poor compared to synthetic films. One strategy to improve these properties is the incorporation of nanoparticles. The particles can also serve as a vehicle for the addition of antioxidant agents into the films. The objective of this work is to optimize the formulation for the preparation of amaranth flour films treated with antioxidant chia (Salvia hispanica L.) extract-loaded chitosan particles using response surface methodology (RSM). Experimental approach. Chitosan nanoparticles with the extract were synthesized by ionic gelation, and the films were made by the casting method. Three independent variables were assigned: amaranth flour (4-6%), glycerol (25-35%) and chitosan nanoparticles loaded with the chia extract (0-0.75%). We then evaluated the physical (thickness), mechanical (tensile strength, Young´s modulus and elongation), barrier (water vapor permeability, moisture and water solubility) and antioxidant properties of the films. The experimental results of the properties were analyzed using a Box-Behnken experimental design generating 15 runs with three replicates at the central point. Results and conclusions. Second and third order polynomial models were obtained from the ANOVA analysis of the evaluated responses, and high coefficients of determination were found (0.91–1.0). The water vapor permeability of the films was 0.82−2.39·10-7 (g·mm)/(Pa·s·m2), tensile strength was 0.33−1.63 MPa and antioxidant activity 2.24−5.65%. The variables had different effects on the films: glycerol negatively affected their properties, and the permeability values increased with increased amaranth flour content. The nanoparticles improved the mechanical, barrier and antioxidant properties of the films compared to the films without nanosystems. The optimal formulation was 4% amaranth flour, 25% glycerol and 0.36% chitosan nanoparticles. The optimized films had better mechanical (1.62 MPa) properties, a low water vapor permeability value (0.91·10-7 (g·mm)/(Pa·s·m2)) and moderate antioxidant activity (6.43%). Novelty and scientific contribution. The results show the effect of chitosan nanoparticles on the properties of amaranth flour films for the first time. The resulting equations are useful in the design of food packaging., Pozadina istraživanja. Brašno od amaranta odnosno šćira (Amaranthus hypochondriacus) može se upotrijebiti za izradu filmova s odličnim svojstvom propusnosti vodene pare, što omogućuje čuvanje hrane, no ti filmovi imaju lošija mehanička svojstva od sintetičkih filmova. Jedan od mogućih načina poboljšanja mehaničkih svojstava filmova je dodatak nanočestica, koje ujedno mogu poslužiti kao nosač antioksidansa. Svrha je ovoga rada bila metodom odzivnih površina optimirati pripremu filmova od šćirovog brašna dodatkom čestica kitozana koje sadržavaju antioksidanse iz ekstrakta chia (Salvia hispanica L.) sjemenki. Eksperimentalni pristup. Nanočestice kitozana s ekstraktom chia sjemenki dobivene su ionskim geliranjem, a filmovi su pripremljeni metodom izlijevanja. Određene su tri nezavisne varijable: šćirovo brašno (4-6 %), glicerol (25–35 %) i nanočestice kitozana s ekstraktom chia sjemenki (0–0,75 %). Zatim su procijenjena fizikalna (gustoća), mehanička (vlačna čvrstoća, Youngov modul elastičnosti i istezljivost), barijerna (propusnost vodene pare, vlaga i topljivost u vodi) i antioksidacijska svojstva filmova. Dobiveni su rezultati ispitani pomoću Box-Behnkenovog plana izvođenjem 15 eksperimenata s tri ponavljanja u centralnoj točki. Rezultati i zaključci. Analizom odziva pomoću ANOVA testa dobiveni su modeli oblika polinoma drugog i trećeg stupnja te visoki koeficijenti određivanja (0,91–1,0). Propusnost vodene pare bila je 0,82−2,39·10–7 (g·mm)/(Pa·s·m2), vlačna čvrstoća 0,33−1,63 MPa, a antioksidacijska aktivnost filmova 2,24−5,65 %. Svaka je varijabla imala drugačiji učinak: povećanje udjela glicerola negativno je utjecalo na svojstva flimova, a njihova propusnost se povećala s povećanjem udjela šćirovog brašna. Dodatkom nanočestica poboljšana su mehanička i antioksidacijska svojstva te propusnost filmova u usporedbi s filmovima koji nisu sadržavali nanočestice. Optimalni dodatak filmovima bio je 4 % šćirovog brašna, 25 % glicerola i 0,36 % nanočestica kitozana. Optimirani filmovi imali su bolja mehanička svojstva (1,62 MPa), malu propusnost vodene pare (0,91·10–7 (g·mm)/(Pa·s·m2)) i umjerenu antioksidacijsku aktivnost (6,43 %). Novina i znanstveni doprinos. Rezultati ispitivanja po prvi put prikazuju utjecaj nanočestica kitozana na svojstva filmova od šćirovog brašna. Dobivene jednadžbe mogu se korisno upotrijebiti u projektiranju jestive ambalaže.

The use of methanol and ethanol for the extraction of antioxidant compounds in Chia Seed (Salvia hispanica L.) is studied, but only the effect of a single concentration of these solvents was evaluated. However, factors such as the nature and the concentration of the solvents determines the content of phenolic compounds, the antioxidant capacity and the possible use of the extract. For this reason, it is necessary to have a detailed study of different extraction conditions to find the optimum. The objective of this work was to evaluate the effect of different concentrations of ethanol and methanol and the hexane treatment on the extraction of phenolic compounds and the antioxidant capacity of the Chia Seeds extracts. The greatest total phenolic content was obtained in the 50% aqueous ethanol and methanol extracts. Nevertheless, all the extracts showed a high DPPH scavenging activity. With exception of 100% ethanol extract, no significant differences were found between the extracts treated with and without hexane. No significant differences were found in the extraction yields of the 80% aqueous ethanol and methanol extracts, but the aqueous methanol extract presented lower IC50. The FTIR and UV-VIS spectra of the aqueous ethanol and methanol Chia extracts suggest differences in the composition of the extracts. It is possible to extract the phenolic compounds from the Chia Seeds with different concentration of ethanol and methanol, which will allow to select the appropriate extraction conditions according to the application of the extract.

Amaranth (Chitosan nanoparticles with the extract were synthesized by ionic gelation, and the films were made by the casting method. Three independent variables were assigned: amaranth flour (4-6%), glycerol (25-35%) and chitosan nanoparticles loaded with the chia extract (0-0.75%). We then evaluated the physical (thickness), mechanical (tensile strength, Young´s modulus and elongation), barrier (water vapor permeability, moisture and water solubility) and antioxidant properties of the films. The experimental results of the properties were analyzed using a Box-Behnken experimental design generating 15 runs with three replicates at the central point.Second and third order polynomial models were obtained from the ANOVA analysis of the evaluated responses, and high coefficients of determination were found (0.91-1.0). The water vapor permeability of the films was 0.82-2.39·10The results show the effect of chitosan nanoparticles on the properties of amaranth flour films for the first time. The resulting equations are useful in the design of food packaging.

Chia (Salvia hispanica L.) seeds contain antioxidants with great benefits for health and are widely used in the food industry. Antioxidants can be degraded by environmental factors, decreasing their biological activity. Their encapsulation in chitosan (CH) particles represents an alternative to protect them and increases their application. The encapsulation efficiency (%EE) of the antioxidants in the CH particles depends on the synthesis conditions. In this study, two methods for encapsulation of chia extract in chitosan particles were evaluated: method A, 0.05% CH in 1% acetic acid was mixed with 0.07% of tripolyphosphate (TPP) and method B, 0.3% CH in 2% acetic acid was mixed with 1% TPP. The results showed that the %EE decreased with the concentration of the extract, and the FTIR analysis suggested that the compounds of the extract were adsorbed on the surface of the particles. Dynamic light scattering and zeta potential analysis showed that the particles of method A are unstable and with a tendency to agglomerate, and the particles of method B are stable. The highest %EE was obtained with 0.2 mg·mL−1 (method A) and 1.0 mg·mL−1 (method B) of the extract. The higher loading capacity (%LC) (16–72%) was exhibited by the particles of method A. The best particle yield (62–69%) was observed for method B. The particles with the extract adsorbed showed antioxidant activity (5–60%) at 25°C; however, in the particles with the extract encapsulated, the activity increased after subjecting to acidic conditions at 40°C due to the breakdown of the particles. The results obtained will allow choosing the appropriate conditions for the synthesis of chitosan particles loaded with chia extracts with specific characteristics (%EE, %LC, size, and type) according to their future applications. The particles could be used in food and pharmaceutical industries and even in edible films for food packaging.

Metabolic syndrome comprises a cluster of diseases like hypertension, dyslipidemia, and insulin resistance, among others. Its treatment is based on lifestyle modification, however, this treatment often fails to improve metabolic syndrome indicators over the long term. In this work, sequences of some representative vegetable proteins were explored to find bioactive peptides with activity toward metabolic disorders of metabolic syndrome. Five proteins, i.e., legumin (chickpea), glutelin type A-2 (chickpea), glutelin type B-2 (rice), prolamin PPROL 17 (maize), and glutelin (rice) revealed a high potential to be effective against metabolic syndrome. We designed and evaluated in silico modifications to their amino acid sequence to release bioactive peptides after simulating gastrointestinal digestion (SGD). The approach presented here allows the design of proteins that could combat metabolic syndrome, for later production and study. In the future, these proteins can be used as functional foods.

Introducción: se presentan los resultados de tres proyectos elaborados en el Instituto Tecnológico Superior de Tepexi durante el periodo 2014-2015, los cuales buscan el desarrollo de una de las regiones más pobres de México. Metodología: el primer proyecto consistió en la preparación de un producto de higiene bucal a partir de la planta shoquillo (Rhus chondroloma), para lo cual se valoraron infusiones de la planta con otras especies, determinando su aceptación mediante una evaluación sensorial. En el segundo proyecto se elaboró un bloque de construcción a partir del desecho de corte de mármol. Esto al combinarlo con otros productos para la construcción, así como al determinar sus propiedades físico-químicas con base en las normas aplicables a estos productos. El último proyecto consistió en la fabricación de un fleje a partir de botellas pet, comprobando así su resistencia y elongación. Resultados: es posible desarrollar un producto natural de higiene bucal sensorialmente agradable al combinar el extracto de la planta con yerbabuena y menta. Con el polvo de mármol se obtuvo un bloque no estructural, dándole así un uso a este desecho y evitando la contaminación. El fleje elaborado a partir de pet cumple con los requerimientos para ser utilizado por las industrias de la región. Conclusión: los proyectos han permitido a la comunidad académica del instituto interactuar con las comunidades donde se elaboraron los mismos, ya que el objetivo principal es impactar en el desarrollo sustentable de la región.