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1.
Polymers (Basel) ; 16(19)2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39408496

RESUMO

This study investigates the effectiveness of various chemical methods, both ultrasound-assisted and non-assisted, for extracting cellulose from banana pseudostem (BPS) waste, comparing the results with commercial pine and eucalyptus cellulose fibers. Delignification treatments with NaOH (25% and 30%) and H2O2 (8%) were evaluated, applied with both conventional and focused sonication. Ultrasound-assisted methods, particularly with NaOH, achieved cellulose percentages as high as 99.5%. X-ray diffraction (XRD) analysis revealed that NaOH treatments significantly increased the cellulose crystallinity index, reaching up to 67.9%, surpassing commercial fibers. Scanning electron microscopy (SEM) results showed that NaOH treatments, especially at 30%, improved fiber morphology and exposure. Thermogravimetric analysis (TGA) indicated that methods using NaOH and focused sonication enhanced the thermal stability of the cellulose. Compared to commercial fibers, some samples obtained with the proposed methods demonstrated higher purity, yield, and thermal stability, highlighting the effectiveness of ultrasound-assisted and NaOH methods.

2.
Data Brief ; 37: 107167, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34113704

RESUMO

In this work, we present data related to the structural features and thermal characteristics of starches from four varieties banana, likewise, we present the synthesis and characterization of starch nanoparticles from those starches. Data shows the structure of the starch granule and the nanoparticles are formed through XRD spectroscopy.

3.
Heliyon ; 6(8): e04763, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32904330

RESUMO

In recent years, interest has increased in the search for new starch sources, especially among Andean tubers, such as Arracacha (or Peruvian Carrot). This work studied the chemical composition, structural features, and thermal and adsorption properties of four sub-varieties of yellow Arracacha grown in Colombia: comun (Com), cartagenera (Car), yema de huevo (YH) and clon 22 (C22). Starches from the Com, Car and YH sub varieties presented similar properties, amylose content around 30%, relative crystallinity around 31% and gelatinization temperature around 60 °C. On the other hand, starch from the Clon 22 (C22) variety presented the highest amylose content, leading to an increase in gelatinization temperature (63 °C), and lower relative crystallinity (24%). Furthermore, digestibility studies show that C22 presented a higher resistant starch content. Our results show that Arracacha is a very interesting starch source, despite few studies on the properties of the different sub-varieties.

4.
J Sci Food Agric ; 99(14): 6392-6399, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31283024

RESUMO

BACKGROUND: Starch nanoparticles have become among the most interesting nanovehicles for drug delivery because of their relatively easy synthesis, biocompatibility, and numerous botanical sources. Starch nanoparticles obtained from green bananas were cross-linked with citric acid and loaded with ß-carotene. RESULTS: Mean particle size, encapsulation efficiency, and ß-carotene release in simulated gastric and intestinal fluids and food simulants were studied. Cross-linked nanoparticles showed higher loading efficiency and encapsulation capacity, indicating that they can accommodate more molecules than their unmodified counterparts, while mathematical models showed a diffusion of released ß-carotene into food simulant media. CONCLUSIONS: Cross-linked nanoparticles showed more controlled release under gastric conditions, mainly in the simulated intestinal fluid, indicating that they are suitable as vehicles for intestine-specific targeting. This controlled released was also observed in food simulants, with lower release values in the more aqueous simulants. © 2019 Society of Chemical Industry.


Assuntos
Musa/química , Extratos Vegetais/química , beta Caroteno/química , Ácido Cítrico/química , Sistemas de Liberação de Medicamentos , Excipientes/química , Tamanho da Partícula , Amido/química
5.
J Org Chem ; 84(3): 1185-1191, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30608687

RESUMO

The effect of interfacial water entrapped in two types of catanionic reverse micelles (RMs) on the kinetic parameters of the SN2 reaction between dimethyl-4-nitrophenylsulfonium trifluoromethanesulfonate (S+) and n-butylamine (BuNH2) was explored. Two catanionic surfactants, composed of a mixture of oppositely charged ionic surfactants without their original counterions, were used to create the RMs. Thus, benzyl- n-hexadecyldimethylammonium 1,4-bis(2-ethylhexyl) sulfosuccinate (BHD-AOT) and cetyltrimethylammonium 1,4-bis(2-ethylhexyl) sulfosuccinate (CTA-AOT) were formed. Also, the well-known anionic surfactant sodium 1,4-bis(2-ethylhexyl) sulfosuccinate (Na-AOT) was employed as a comparison. Our results showed an important catalytic-like effect of all RMs investigated in comparison with a water-benzene mixture, and the rate constant values depend on the type of surfactant used. Faster reaction in BHD-AOT RMs than in CTA-AOT and Na-AOT RMs was observed. This behavior was attributed to the strong interaction (by hydrogen bonding with AOT anion and ion-dipole interaction with BHD+) between the entrapped water and the BHD-AOT interface, which reduces the solvation capacity of water on S+. In CTA-AOT (and Na-AOT) RMs, the water-interface interaction is weaker and the electron pairs of water can solvate S+ ions. In summary, the chemical structure of the counterion on the catanionic surfactant alters the interfacial region, allowing the progress of a reaction inside the RMs to be controlled.

6.
J Texture Stud ; 50(2): 148-154, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30548624

RESUMO

Growing interest in processed frozen products with similar characteristics to natural products has generated the study of new products in the food industry field. The characteristics of each matrix, the process of elaboration, composition, and structure of the additives and the interactions amongst these modify the food's texture, structure, physical and sensory properties and, hence, interfere directly with consumer acceptance. This research studied the effect of adding cryoprotectors during frozen storage on the rheological, physicochemical, structural, and microbiological properties in a Mafafa-quinoa-olive oil puree. To carry out the study, the rheological properties were determined through dynamic oscillatory tests and in steady state; likewise, the physicochemical properties (humidity, color, pH, and syneresis) were analyzed. Regarding physicochemical properties, the humidity content in the purees formulated varied between 57 and 74%, without important variation (p > .05) with respect to the formulation, however, in the storage during the freezing/thawing process, this parameter diminished in greater proportion in those purees containing carrageenan as cryoconservant. Both the addition of cryoconservants and the storage time affected significantly (p < .05) the puree's syneresis, with the degree of exudation being lower in the formulation containing xanthan gum at 1% w/w. During the freezing/thawing process, decreased apparent viscosity was noted. Additionally, the analysis of the viscoelastic properties of the purees evidences that already described, given that a significant effect (p < .05) was observed of the formulation of purees in the elastic component G', in contrast with a notable decrease in the viscous component G″.


Assuntos
Fenômenos Químicos , Chenopodium quinoa/química , Crioprotetores/farmacologia , Reologia , Xanthosoma/química , Aditivos Alimentares/farmacologia , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Congelamento , Azeite de Oliva/química , Polissacarídeos Bacterianos , Viscosidade
7.
Food Sci Technol Int ; 24(8): 705-712, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30060685

RESUMO

Edible films are among the most promising fields in food science over the last decade due to their versatility (they can be made from a wide array of materials) and because they can be used as carriers of different active substances, like antioxidants, antimicrobial agents, and essential oils from plants. In the case of the essential oils, their inclusion in edible films is limited by their low water solubility. Nanoemulsions are thermodynamically stable and transparent systems that can be used as a way of incorporating essential oils into edible film matrices. In this paper, we developed lemongrass and rosemary essential oil nanoemulsions by using a low-energy method, observing the effect of the surfactant/oil ratio in their physicochemical properties. Then we studied the effect of the nanoemulsions concentration incorporated into banana starch edible films. We observed that essential oils' nanoemulsions have a plasticizing effect increasing the film's water vapor permeability, transparency, and elongation at break, while the hydrophobic nature of the essential oils lead to a decrease in their water solubility.


Assuntos
Cymbopogon/química , Emulsões , Embalagem de Alimentos/métodos , Musa/química , Óleos Voláteis , Rosmarinus/química , Amido/química , Anti-Infecciosos , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas , Permeabilidade , Plastificantes , Solubilidade , Vapor
8.
J Sci Food Agric ; 98(11): 4042-4049, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29377147

RESUMO

BACKGROUND: Aloe vera (AV) gel is a promising material in food conservation, given its widely reported antimicrobial and antioxidant activity; however, its application in the formation of edible films and coatings has been small owing its low film-forming capability. The aim of this study was to investigate the physicochemical properties of film-forming solutions and films prepared using unripe banana starch-chitosan and AV gel at different AV gel concentrations. RESULTS: Our results showed that AV gel considerably affected the rheological and optical properties of the edible coatings, mainly due to increased amounts of solids brought by the AV gel. Film-forming capacity and physicochemical properties were also studied; most of the film properties were affected by the inclusion of AV gel, with decreased water vapor permeability, tensile strength and elongation at break. Fourier transform infrared studies showed that the inclusion of AV gel disrupts the interaction between starch and chitosan molecules; however, further studies are needed to fully understand the specific interactions between the components of AV gel and both starch and chitosan molecules. CONCLUSION: Our results suggest that the addition of AV gel creates a crosslinking effect between the phenolic compounds in AV gel and starch molecules, which disrupts the starch-chitosan interaction and greatly affects the properties of both the film-forming solution and edible films. © 2018 Society of Chemical Industry.


Assuntos
Quitosana/química , Embalagem de Alimentos/instrumentação , Musa/química , Extratos Vegetais/química , Preparações de Plantas/química , Polímeros/química , Amido/química , Aloe/química , Permeabilidade , Polímeros/síntese química , Resistência à Tração
9.
Int J Biol Macromol ; 111: 498-504, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29337095

RESUMO

In recent years, starch nanoparticles have been of great interest for drug delivery due to their relatively easy synthesis, biocompatibility, and vast amount of botanical sources. Native and acetylated starch obtained from green bananas were used for synthesis of curcumin-loaded starch nanoparticles. Mean particle size, encapsulation efficiency, and curcumin release in simulated gastric and intestinal fluids were studied. Both nanosystems showed sizes lower than 250 nm and encapsulation efficiency above 80%, with acetylated banana starch nanoparticles having the capacity to encapsulate more curcumin molecules. Both FTIR and XRD analyses showed that starch acetylation allows stronger hydrogen bond interaction between curcumin and the starch matrix, thus, higher encapsulation efficiency. Finally, curcumin release studies showed that acetylated banana starch nanoparticles allowed more controlled release, probably due to their stronger hydrogen bond interaction with curcumin.


Assuntos
Curcumina/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Amido/química , Curcumina/uso terapêutico , Humanos , Musa/química , Nanopartículas/uso terapêutico , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/uso terapêutico
10.
Chemistry ; 18(49): 15598-601, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-23129102

RESUMO

Catanionic surfactants: the synthesis of a new surfactant ionic liquid with unique properties is described. The formation of reverse micelles in benzene and large unilamellar vesicles, formed spontaneously without the help of any mechanical of chemistry methods, in water is demonstrated by using dynamic light scattering and small-angle X-ray scattering techniques.

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