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1.
Food Res Int ; 176: 113793, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163707

RESUMO

The present study evaluated the effect of cryoconcentration of pulp blocks of acerola (Malpighia emarginata DC). The study evaluated cryoconcentration in three stages. The cryoconcentrated samples, the ice fractions, and the initial pulp were evaluated for physicochemical composition, bioactive composition, and multielement profile. The cryoconcentrated sample obtained in the third stage of cryoconcentration showed the best results for the concentration factor, process efficiency, total soluble solids content, red color intensity, and increasing of the macro and micronutrients: Cu, Ca, S, Sr, K, Mn, Na, P, Mg, Fe. All stages presented good performance in the total soluble solids content, increase in the titratable acidity of the concentrates, and progressive increase in the intensity of the red color. Generally, higher levels of total phenolic and antioxidant activity were found for the 2nd and 3rd concentrates. The phenolic activity showed an increase of 166.90% in the 3rd stage concentrate compared to fresh pulp, and the antioxidant activity was 112.10% by the ABTS method and 131.60% by the DPPH method, both in the 3rd stage concentrate. The major individual polyphenols were Ferulic acid, Protocatechuic acid, and Taxifolin, with significant increases in the concentration of the compounds in the 2nd and 3rd stage concentrates. In addition, the contents of potentially toxic metals were below detection limits. During the cryoconcentration process, there was a decrease in the values ​​of vitamin C content, moisture content, density, and elements Cu, Sr, and Zn.


Assuntos
Antioxidantes , Espectrometria de Massas em Tandem , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Ácido Ascórbico/análise , Vitaminas/análise , Rutina/análise , Fenóis/análise
2.
Environ Sci Pollut Res Int ; 30(50): 109423-109437, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37775630

RESUMO

Contamination of water by toxic dyes is a serious environmental problem. Adsorbents prepared by an environmentally safe route have stood out for application in pollutant removal. Herein, iron oxide-based nanomaterial composed of Fe(III)-OOH and Fe(II/III) bound to proanthocyanidins, with particles in the order of 20 nm, was prepared by green synthesis assisted by extract of açaí (Euterpe oleracea Mart.) berry seeds from an agro-industrial residue. The nanomaterial was applied in the adsorption of cationic dyes. Screening tests were carried out for methylene blue (MB), resulting in an outstanding maximum adsorption capacity of 531.8 mg g-1 at 343 K, pH 10, 180 min. The kinetics followed a pseudo-second-order model and the isotherm of Fritz-Schülnder provided the best fit. Thermodynamic data show an endothermic process with entropy increase, typical of chemisorption. The proposed mechanism is based on the multilayer formation over a heterogeneous adsorbent surface, with chemical and electrostatic interactions of MB with the iron oxide nanoparticles and with the proanthocyanidins. The high adsorption efficiency was attributed to the network formed by the polymeric proanthocyanidins that entangled and protected the iron oxide nanoparticles, which allowed the reuse of the nanomaterial for seven cycles without loss of adsorption efficiency.


Assuntos
Euterpe , Proantocianidinas , Poluentes Químicos da Água , Compostos Férricos , Corantes , Adsorção , Termodinâmica , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Azul de Metileno/química
3.
Food Res Int ; 162(Pt B): 112144, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461365

RESUMO

This work presents the enrichment of powdered dairy compounds with soy extract, and the determination of its physical properties, rehydration characteristics, multielement profile, and polyphenolic potential. Five dairy compound formulations were developed, where milk powder was replaced by 10, 20, 30, 40, and 49 % w/w of soy extract.. Multivariate analyzes using combined PCA analyzes were used to group the samples and, thus, reveal the main characteristics associated with their physicochemical properties, bioactive composition, and multi-element profile. The protein content in the samples was not significantly affected by the addition of soy extract. There was a gradual increase in the total fat as the concentration of soy extract increased. Furthermore, with the increase in the percentage of soy extract in the dairy compounds, there was an increase in the levels of total polyphenols, total flavonols, and antioxidant capacity, and of some minerals, such as Fe, Mn, P, Cu, and Mg. The DC49 sample showed the highest values for total polyphenols (178.65 mg of gallic acid (GAE)/100 g) and total flavonols (1.51 mg of catechin/100 g). The addition of soy extract promoted the enrichment of important minerals in the samples, with an increase of up to 55 times in the Fe content and up to 40 times in the Mn content. Physical properties (density and fluidity) and rehydration properties (wetting, dispersibility, and solubility) also were affected as the percentage of soy extract in the samples increased. When there was an addition of up to 20 % soy extract, the samples are still wettable. All dairy compounds showed solubility above 69 %. The use of soy extract in the polyphenolic and mineral enrichment of the dairy compounds is important to add nutritional value to powdered milk, we emphasize that this product has enormous potential to be used in diets that require mineral supplementation.


Assuntos
Fabaceae , Glycine max , Pós , Hidratação , Flavonóis , Polifenóis , Extratos Vegetais
4.
Food Chem ; 228: 447-454, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28317748

RESUMO

An in vitro method involving simulated gastrointestinal digestion was used to assess the bioaccessibility of fifteen minerals, twenty-two phenolic compounds and the antioxidant capacity in juçara fruit during seven ripening stages. For minerals and phenolics, respectively, initial contents were up to 1325.9 and 22.9mg100g-1, whereas after in vitro digestion, the maximum values were 556.7 and 14.43mg100g-1 (dry matter). Antioxidant capacity, determined by 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP), after in vitro digestion decreased 51-78% when compared to the crude extract. Bioaccessible fractions of quercetin, protocatechuic and p-coumaric acids presented positive and significant correlation with results of DPPH and FRAP. Furthermore, our study demonstrated that the ripening stages of juçara fruit influenced the bioaccessibility of compounds and antioxidant capacity, which presented higher levels in purple fruits collected 42-69days after the appearance of the red berries on bunches.


Assuntos
Euterpe/química , Frutas/química , Antioxidantes/análise , Digestão
5.
Plant Foods Hum Nutr ; 71(4): 422-428, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27738868

RESUMO

Grape and grape derivatives contain a variety of antioxidants that have gain increasing interest for functional foods applications. The chemical composition of grapes is mainly related to grape variety and cultivation factors, and each grape constituent exhib its unique characteristics regarding its bioactive properties. This study investigated the chemical composition and the effect of drying on the bioactive content of the non-pomace constituent obtained in the processing of organic and conventional grape juices from V. labrusca L. The non-pomace samples were analyzed for polyphenols, monosaccharides, antioxidant activity and elemental composition and the effect of drying on the bioactive composition was evaluated in samples subjected to lyophilization and drying with air circulation. The analyses revealed high concentrations of proanthocyanidins, flavanols and anthocyanins, and high antioxidant capacity of the organic and conventional samples. The drying processes reduced significantly (P < 0.05) the total phenolic content that ranged from 13.23 to 36.36 g/kg. Glucose, xylose, and mannose were the predominant monosaccharides, whereas K, Ca and Mg were the most abundant minerals. Variations in the chemical composition of organic and conventional samples were associated with cultivation factors. Nevertheless, this non-pomace constituent is a promising source of nutrients and polyphenols with bioactive potential.


Assuntos
Dessecação , Alimentos Orgânicos/análise , Sucos de Frutas e Vegetais/análise , Monossacarídeos/análise , Compostos Fitoquímicos/análise , Antocianinas/análise , Antioxidantes/análise , Manipulação de Alimentos , Frutas/química , Polifenóis/análise , Proantocianidinas/análise , Vitis/química
6.
Food Chem ; 173: 527-35, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466055

RESUMO

Grapes are rich in polyphenols with biologically active properties. Although the bioactive potential of grape constituents are frequently reported, the effects of Brazilian Vitis labrusca L. grape juices ingestion have not been demonstrated in humans. This study identified the phenolic and elemental composition of red and white grape juices and the effect of organic and conventional red grape juice consumption on lipid peroxidation in healthy individuals. Concentrations of anthocyanins, flavanols and phenolic acids and the in vitro antioxidant activity were significantly higher in the organic juice. The macro-elements K, Ca, Na and Mg were the most abundant minerals in all juices. The acute consumption of red grape juices promoted significant decrease of lipid peroxides in serum and TBARS levels in plasma. It is concluded that red V. labrusca L. grape juices produced in Southern Brazil showed lipid peroxidation inhibition abilities in healthy subjects, regardless of the cultivation system.


Assuntos
Bebidas/análise , Peroxidação de Lipídeos/efeitos dos fármacos , Fenóis/análise , Vitis/química , Adulto , Antocianinas/análise , Antioxidantes/farmacologia , Brasil , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal
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