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1.
Plant Foods Hum Nutr ; 79(1): 242-249, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38329612

RESUMO

This work employed supramolecular solvents (SUPRAS) made up of octanoic acid, ethanol, and acidified water (pH ~ 3) to extract and concentrate bioactive compounds from Eugenia pyriformis Cambess (uvaia) pulp. At first, the SUPRAS phase characterization demonstrated the spherical aggregates' formation with an internal hydrophobic structure and an external hydrophilic media. Subsequently, the simultaneous production and extraction (SUPRAS-SPE) method was employed in the solid-liquid extraction (SLE) of uvaia pulp. The extracts were evaluated through Folin-Ciocalteu reducing capacity, antioxidant activity (DPPH assay), total carotenoid content (TCC), and total flavonoid content (TFC). The results showed that reducing the ethanol concentration in the SUPRAS composition boosted the TCC extraction while increasing the ethanol presence, promoting a high TFC yield. Moreover, the SUPRAS-SPE method was compared with the ex situ method (SUPRAS-ES), where the solvent was previously produced and then applied to the SLE. Both methods were evaluated concerning their EE% and thermal degradation. The SUPRAS-SPE method increased the EE% of uvaia pulp bioactive compounds compared to the SUPRAS-SE method, providing a suitable microenvironment to extract, concentrate, and stabilize carotenoids from uvaia pulp, offering a sustainable alternative to obtain valuable compounds.


Assuntos
Eugenia , Solventes/química , Eugenia/química , Antioxidantes/química , Carotenoides , Etanol
2.
Food Chem ; 440: 138195, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38103506

RESUMO

This work aimed to evaluate the influence of the mechanical defibrillation technique on the pinhão nanosuspensions production obtained from the whole pinhão, its coat, and almond. The nanosuspensions were characterized concerning their composition, morphology, thermal stability, rheological behavior, compound profiling, and cytotoxicity. The results revealed a significant fiber content in pinhão coat nanosuspension (63.12 ± 0.52 %) and non-fiber carbohydrates in whole pinhão (59.00 ± 0.13 %) and almond (74.39 ± 0.23 %) nanosuspensions. The defibrillation process led to micro/nano-sized fibers in pinhão coat nanosuspensions and small-size starch granules in almond nanosuspensions. The nanosuspensions containing pinhão coat exhibited a gel-like behavior, while almond nanosuspensions displayed liquid-like characteristics. Pinhão coat nanosuspensions presented a significant content of flavonoids and phytosterols, whereas almond-based nanosuspensions contained substantial sugar amounts. No cytotoxicity was observed at the concentrations evaluated. These findings demonstrated that the defibrillation technique impacted the properties of pinhão constituents, allowing their application in new product development.


Assuntos
Araucaria , Nanopartículas , Flavonoides , Sementes , Amido , Suspensões , Tamanho da Partícula
3.
Food Chem ; 303: 125388, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31454757

RESUMO

Saponins are known for their bioactive and surfactant properties, showing applicability to the food, cosmetic and pharmaceutical industries. This work evaluated the saponins effects on Kluyveromyces lactis ß-galactosidase activity and correlated these changes to the protein structure. Enzyme kinetic was evaluated by catalytic assay, protein structure was studied by circular dichroism and fluorescence, and isothermal titration calorimetry was used to evaluate the interactions forces. In vitro enzymatic activity assays indicated an increase in the protein activity due to the saponin-protein interaction. Circular dichroism shows that saponin changes the ß-galactosidase secondary structure, favoring its protein-substrate interaction. Besides, changes in protein microenvironment due to the presence of saponin was observed by fluorescence spectroscopy. Isothermal titration calorimetry analyses suggested that saponins increased the affinity of ß-galactosidase with the artificial substrate o-nitrophenyl-ß-galactoside. The increase in the enzyme activity by saponins, demonstrated here, is important to new products development in food, cosmetic, and pharmaceutical industries.


Assuntos
Kluyveromyces/enzimologia , Saponinas/farmacologia , beta-Galactosidase/efeitos dos fármacos , Calorimetria , Dicroísmo Circular , Cinética , Nitrofenilgalactosídeos/metabolismo , Casca de Planta/química , Estrutura Secundária de Proteína , Quillaja/química , Espectrometria de Fluorescência , beta-Galactosidase/metabolismo
4.
Int J Biol Macromol ; 136: 486-492, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31207325

RESUMO

Tannins, proteins, and divalent cations interactions are important for many processes in the food industry and human and animal nutrition and health. The effect of magnesium, calcium, and manganese on the interaction, turbidity, and in vitro protein digestibility of bovine serum albumin and tannic acid complexes was studied. The divalent cations increase the affinity and influence the enthalpy and entropy changes of the protein and tannin binding. Magnesium maintained the nature of interactions, and calcium and manganese changed the binding mechanism. The factor that most influenced turbidity was the tannic acid and divalent cations binary interaction. Samples containing tannic acid and magnesium and calcium decreased the protein digestibility. Manganese increased the in vitro protein digestibility when compared with samples without salt addition; nevertheless, the complexes formed was higher. These finds can help in the understanding of interactions involved food system and in physiological conditions.


Assuntos
Cátions Bivalentes/farmacologia , Soroalbumina Bovina/metabolismo , Taninos/metabolismo , Animais , Bovinos , Digestão/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica , Termodinâmica
5.
Food Chem ; 275: 346-353, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724206

RESUMO

Tannins are compounds with antinutrient properties that hinder food digestibility, prejudicing human and animal nutrition. This work aimed to evaluate the negative effects of tannic acid on Kluyveromyces lactis ß-galactosidase catalytic activity and correlate these changes with the protein structure. ß-Galactosidase activity decreased in the presence of tannins, which caused changes to the structure of the enzyme, as demonstrated by circular dichroism. It was verified that tannin binds to the protein by a static mechanism. Additionally, isothermal titration calorimetry suggested that tannic acid modified the molecular interaction between ß-galactosidase and o-nitrophenyl-ß-d-galactoside, reducing their affinity and prejudicing the protein activity. This study helps to understand the effects of tannins on the ß-galactosidase structure and how they are related to the enzyme catalytic activity. The alterations in the conformation and activity of the enzyme should be taken into consideration when dairy products are consumed with tannin-rich food.


Assuntos
Kluyveromyces/enzimologia , Taninos/metabolismo , beta-Galactosidase/química , beta-Galactosidase/metabolismo , Animais , Calorimetria/métodos , Dicroísmo Circular , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Humanos , Cinética , Nitrofenilgalactosídeos/química , Nitrofenilgalactosídeos/metabolismo , Conformação Proteica , Espectrometria de Fluorescência , Taninos/química , Termodinâmica
6.
J Agric Food Chem ; 66(40): 10543-10551, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30227705

RESUMO

Phytate decreases mineral and protein availability and influences protein properties, such as solubility and stability. The binding constants and turbidity data can help with the understanding of the influence of phytate and divalent salts on protein behavior. Ternary complexes formed between bovine serum albumin, sodium phytate, and divalent salts were investigated by isothermal titration calorimetry, turbidity, and in vitro protein digestibility. Results showed a positive entropy change and a negative and small enthalpy change as a result of electrostatic binding forces and ternary and binary complex precipitation. The interaction was favored for the systems containing calcium and manganese, whereas those containing magnesium showed a low heat of interaction. Despite the high protein digestibility, the stability of divalent phytates in a wide pH range may decrease mineral bioavailability. These results can provide important insights for the study of mineral bioavailability and diverse processes that involve protein and minerals in several areas of knowledge.


Assuntos
Cálcio/química , Magnésio/química , Ácido Fítico/química , Soroalbumina Bovina/química , Animais , Cálcio/metabolismo , Bovinos , Digestão , Magnésio/metabolismo , Modelos Biológicos , Ácido Fítico/metabolismo , Ligação Proteica , Soroalbumina Bovina/metabolismo , Solubilidade , Termodinâmica
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