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1.
Food Res Int ; 173(Pt 1): 113324, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803635

RESUMO

The aim of this study was to investigate the inhibitory effects of Actinidia arguta ('Weiki', 'Skarlet September Kiwi') and Actinidia kolomikta ('Lande') fruit extracts against advanced glycation end-products (AGEs) formation and acetylcholinesterase (AChE) activity. The extracts were also tested regarding polyphenol profile and Lascorbic acid content (UHPLC-DAD-MS), and antioxidant capacity (DPPH, ABTS). 'Scarlet September Kiwi' showed the strongest anti-AGEs activity studied with BSAGLU (IC50 = 2.68) and BSA-MGO (IC50 = 18.06) models. The highest anti-AChE activity was found for the 'Lande' extract (IC50 = 4.56). 'Lande' showed the highest L-ascorbic acid content (8271.96 µg/g dw), ABTS (312.42 µmol TE/g dw) and DPPH (282.01 µmol TE/g dw) values. 'Scarlet September Kiwi' revealed the highest individual phenolics concentration (2321.43 µg/g dw). The contents of (+)-catechin and L-ascorbic acid were significantly correlated with anti-AChE activity. This research sheds new light on the bioactivity of Actinidia arguta and Actinidia kolomikta fruit elucidating the role of (+)-catechin and L-ascorbic acid in prevention of Alzheimer's disease.


Assuntos
Actinidia , Catequina , Antioxidantes/análise , Polifenóis/farmacologia , Polifenóis/análise , Actinidia/química , Frutas/química , Catequina/análise , Antagonistas Colinérgicos/análise , Acetilcolinesterase , Extratos Vegetais/química , Ácido Ascórbico/análise
2.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144650

RESUMO

HS-SPME/GC-MS analysis was carried out to characterize the profile of volatile organic compounds (VOCs) in kiwiberry cultivars (Geneva and Weiki) exposed to high hydrostatic pressure (HHP) (450-550-650/5 and 15 min). The sum of individual VOCs in Geneva (6.493 mg/kg) and Weiki (11.939 mg/kg) samples was found to be significantly reduced after processing, particularly for pressurization conditions of 650 MPa/15 min (decrease of 62%) and 550 MPa/15 min (decrease of 84%), respectively. On the other hand, Geneva and Weiki exposed to 450 MPa/5 min manifested the lowest loss in the sum of the VOCs. Geneva exposure to 450 MPa/5 min led to an increase in the hexanal (r = 0.782) and linalool (r = 0.806) content. Sample pressurization (450 MPa/15 min) promoted the formation of methyl butanoate, ethyl hexanoate, and cis-geraniol, simultaneously increasing the benzaldehyde (r = 0.886) concentration. However, the treatment of Weiki at 450 MPa/5 min favored trans-2-heptenal (r = 0.999) and linalool (r = 0.970) formation, as well as the (-)-terpinen-4-ol (r = 0.848) and geraniol (r = 0.694) content. Ethyl butanoate, hexanal, and 1-octen-3-ol were highly concentrated in the HHP-treated (450 MPa/5 or 15 min) Weiki. Pressurization decreased the terpenoid contribution, but also increased the contribution of alcohols and aldehydes to the overall VOC number in both tested cultivars.


Assuntos
Actinidia , Compostos Orgânicos Voláteis , Monoterpenos Acíclicos , Álcoois/análise , Aldeídos/análise , Benzaldeídos/análise , Cromatografia Gasosa-Espectrometria de Massas , Pressão Hidrostática , Odorantes/análise , Microextração em Fase Sólida , Terpenos/análise , Compostos Orgânicos Voláteis/análise
3.
Food Chem ; 343: 128421, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268172

RESUMO

This study analysed the impact of high pressure processing (HHP) on the inhibitory effects (IC50) of kiwiberries (cv. 'Weiki'), on the formation of advanced glycation end-products (AGEs) and the activity of angiotenisn-converting enzyme (ACE) and the enzyme acetylcholinesterase (AChE). The polyphenol profile (HPLC-MS/MS) and antioxidant capacity (PCLACW, ABTS, FRAP) were also studied. HHP-treated 'Weiki' (450 MPa/5 min and 650 MPa/5 min) was the most potent inhibitor of AGEs in the BSA-GLU model (6.52 mg/mL on average) relative to other materials (12.09-7.21 mg/mL). Among all samples assayed in the BSA-MGO model (61.97-14.48 mg/mL), HHP-treated 'Weiki' (450 MPa/5 min) showed the highest anti-AGE activity (12.37 mg/mL). Pressurization (450 MPa/5 min) significantly enhanced the anti-ACE (14.09 mg/mL) and anti-AChE (16.95 mg/mL) potentials of the tested extract relative to the other materials (23.75-14.50 mg/mL and 37.88-19.69 mg/mL, respectively). Pressurization increased polyphenol content and antioxidant capacity of the samples analysed.


Assuntos
Actinidia/química , Indústria de Processamento de Alimentos/métodos , Extratos Vegetais/farmacologia , Polifenóis/análise , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Antioxidantes/análise , Antioxidantes/química , Antagonistas Colinérgicos/farmacologia , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Frutas/química , Produtos Finais de Glicação Avançada/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Hipoglicemiantes/farmacologia , Extratos Vegetais/química , Polifenóis/química , Pressão , Espectrometria de Massas em Tandem
4.
Int J Food Sci ; 2020: 4350461, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32964013

RESUMO

The effect of processing such as high hydrostatic pressure (HHP) (400-600 MPa/15 min) or low pasteurization temperature (LPT) (74°C/2 min) or high pasteurization temperature (HPT) (90°C/1 min) on selected quality parameters of juice obtained from hydroponically cultivated beef tomatoes was investigated. The total polyphenols content (TPC), total phenolic index (TPI), Trolox equivalent antioxidant capacity (ABTS) and ferric reducing antioxidant power (FRAP) were analysed in the fresh and processed juices stored for 0, 7 and 14 days. What is more, colour parameters (L ∗, a ∗, b ∗, ∆E), the activity of polyphenol oxidase (PPO) and peroxidase (POD) and microbial stability were also analyzed following the juices storage. Among all the tested samples, the juice exposed to 600 MPa for 15 min showed superior quality. Samples treated with 600 MPa for 15 min and stored for 0, 7 and 14 days had high TPC, TPI, ABTS, FRAP and a ∗ values. As demonstrated, these tested samples at the end of the storage period retained 90% and 95% of their polyphenol content and antioxidant capacity, respectively. As in the case of pasteurization, juice processing at 600 MPa for 15 min clearly reduced the activity of food-spoiling enzymes (PPO, POD) as well as the microbial count. The obtained results showed that TPC was significantly and positively correlated with TPI, ABTS and FRAP parameters.

5.
Foods ; 9(5)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32455966

RESUMO

Light microscopy (LM) is commonly used in the study of biological materials to determine the morphology of cells and tissues. The potential of this technique for studying the structure of food products is also recognized but less known. Especially rare are information regarding LM studies of the supramolecular structure of starch. The aim of the work was to fill this gap by providing data on the possibilities for application of LM in starch studies. It was shown that in spite of an enormous progress in the development of microscopic techniques, including both increase of resolution and improvement of image analysis methods, light microscopy still has a huge potential for starch studies. The advantage of LM over other microscopic techniques is the possibility of differentiating between amylose and amylopectin by iodine staining. That makes LM especially useful in the analysis of the process of gelatinization of starch, the extent of molecular dispersion of its macromolecules, and the changes in its structure caused by modification. Moreover, it can be particularly useful for studying the changes in the supramolecular structure of starch in a food product matrix, providing more information than scanning electron microscopy (SEM)-the most common technique used for these purposes.

6.
PLoS One ; 14(1): e0210694, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30682086

RESUMO

A novel approach for drug design based on the oral carbapenem analog tebipenem pivoxil (TP) has been proposed. The formation of the tebipenem pivoxil-ß-cyclodextrin (TP-ß-CD) complex resulted in changes concerning physicochemical properties of TP, which is significant for planning the development of an innovative pharmaceutical formulation as well as in the modifications of biological activity profile of the studied delivery system. The inclusion of TP into ß-cyclodextrin (ß-CD) was confirmed by spectral (infrared and Raman spectroscopies) and thermal method (differential scanning calorimetry). Precise indications of TP domains responsible for interaction with ß-CD were possible through a theoretical approach. The most important physicochemical modifications obtained as an effect of TP inclusion were changes in solubility and its rate depending on acceptor fluids, and an increase in chemical stability in the solid state. Biologically essential effects of TP and ß-CD interactions were decreased TP permeability through Caco-2 cell monolayers with the use of efflux effect inhibition and increased antibacterial activity. The proposed approach is an opportunity for development of the treatment in resistant bacterial infections, in which along with physicochemical modifications induced by a drug carrier impact, a carrier synergy with a pharmacological potential of an active pharmaceutical substance could be used.


Assuntos
Antibacterianos/química , Antibacterianos/farmacocinética , Carbapenêmicos/química , Carbapenêmicos/farmacocinética , beta-Ciclodextrinas/química , Células CACO-2 , Varredura Diferencial de Calorimetria , Permeabilidade da Membrana Celular/fisiologia , Humanos , Modelos Teóricos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
7.
Food Chem ; 261: 201-209, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29739583

RESUMO

The effect of high hydrostatic pressure (HHP) (450-550-650 MPa/5-10-15 min) on polyphenols profile of purée obtained from commercial tomato varieties (Maliniak, Cerise, Black Prince and Lima) was investigated. Individual polyphenols, total phenolic index (TPI) were quantified using a mass spectrometer (HPLC-MS/MS). Photochemiluminescence (PCLACW), cyclic voltammetry (CV) and ferric reducing antioxidant power (FRAP) assays were used to determine the antioxidant capacity of the hydrophilic extract. The results demonstrated that at certain processing conditions, HHP may enhance or decrease the nutritional quality of tomato purée. However, the tomato variety was a key factor influencing the polyphenols profile and the antioxidant capacity. A significant positive correlation was found among TPI, FRAP or CV parameters and the concentration of caffeic, ferulic, sinapic and p-coumaric acids, and epicatechin. On the other hand, significant positive correlation was observed among antioxidant capacity (PCLACW), TPC, rutin and naringenin concentration as well as chlorogenic and isochlorogenic acids.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos/métodos , Fenóis/análise , Solanum lycopersicum/química , Antioxidantes/química , Catequina/análise , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/análise , Medições Luminescentes , Valor Nutritivo , Fenóis/química , Polifenóis/análise , Pressão , Espectrometria de Massas em Tandem
8.
Food Chem ; 240: 51-58, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28946305

RESUMO

The effect of high hydrostatic pressure processing (650MPa/9min) on molecular mass distribution, and hydrodynamic and structural parameters of amylose (maize, sorghum, Hylon VII) and amylopectin (waxy maize, amaranth) starches was studied. The starches were characterized by high-performance size-exclusion chromatography (HPSEC) equipped with static light scattering and refractive index detectors and by Fourier Transform Infrared (FTIR) spectroscopy. Significant changes were observed in molecular mass distribution of pressurized waxy maize starch. Changes in branches/branch frequency, intrinsic viscosity, and radius of gyration were observed for all treated starches. The combination of SEC and FTIR data showed that α-1,6-glycosidic bonds are more frequently split in pressurized amaranth, Hylon VII, and waxy maize starch, while in sorghum and maize starches, the α-1,4 bonds are most commonly split. Our results show that the structural changes found for pressurized starches were more strongly determined by the starch origin than by the processing applied.


Assuntos
Amido/química , Amilopectina , Amilose , Pressão Hidrostática , Estrutura Molecular , Zea mays
9.
J Food Sci ; 81(9): C2135-42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27447364

RESUMO

Size exclusion chromatography with triple detection as well as infrared spectroscopy studies of commercially available pyrodextrins proved that these molecules are characterized not only by significantly lower molecular mass, in comparison to that of native starch, but also by increased branching. Therefore, pyrodextrins adopt a very compact structure in solution and show Newtonian behavior under shear in spite of their molecular masses of tens of thousands Daltons. The results also indicate that 50% reduction of digestibility of pyrodextrins is, to a minor extent, caused by formation of low-molecular color compounds containing carbonyl functional groups. The main reason is, as postulated in the literature, transglycosidation that leads to decreased occurrence of α-1,4-glycoside bonds in the molecular structure. In the process of dextrinization starch also undergoes changes in supermolecular structure, which, however, have no influence on digestibility. Likewise, the effect of formation of low-molecular colorful compounds containing carbonyl groups is not crucial.


Assuntos
Dextrinas/química , Estrutura Molecular , Cromatografia em Gel , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Food Chem ; 194: 545-54, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26471591

RESUMO

The influence of high hydrostatic pressure (HHP) processing in parallel with oak chip maceration on the physicochemical and sensory properties of a young red wine was investigated preliminarily. Wines were treated by HHP at 250, 450 and 650MPa for up to 45min and French oak chips (5g/L) were added. HHP enhanced the extraction of phenolics from oak chips. The phenolic contents and antioxidant activity of the wine increased after HHP processing in the presence of oak chips. Meanwhile, the anthocyanin content and wine color intensity decreased in the first 5min of pressure treatment and then increased gradually. The multivariate analysis revealed that "pressure holding time" was the key factor affecting wine physicochemical characteristics during HHP processing in the presence of oak chips. Furthermore, oak chip maceration with and without HHP processing weakened the intensities of several sensory attributes and provided the wine with an artificial taste.


Assuntos
Oxigênio/química , Fenóis/análise , Vinho/análise , Catálise , Fenômenos Químicos , Pressão Hidrostática , Madeira
11.
Eur J Pharm Biopharm ; 99: 24-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26592156

RESUMO

Following the preparation of an inclusion complex of ß-cyclodextrin and meropenem, methods based on FT-IR, Raman and DSC were used for its characterization. An analysis of changes in the stability of meropenem after complexation showed that the complex may serve as a valuable delivery system significantly contributing to enhanced meropenem stability in aqueous solutions and in the solid phase. Due to a sustained transfer of meropenem from the cavity of the cyclodextrin it was possible to maintain a constant desired meropenem concentration over a period of 20 h, as confirmed by a release study. An evaluation of microbial activity not only demonstrated that the bactericidal action of meropenem was not stopped as a result of complexation but even pointed to greater growth inhibition in certain clinically important strains. The fact that investigations of meropenem stability and microbial activity proposed the carbonyl groups as those domains of a meropenem molecule that are instrumental in the formation of a complex with ß-cyclodextrin supports the findings of theoretical studies based on molecular modeling.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Tienamicinas/administração & dosagem , Tienamicinas/química , beta-Ciclodextrinas/administração & dosagem , beta-Ciclodextrinas/química , Sítios de Ligação/fisiologia , Substâncias Macromoleculares/administração & dosagem , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Meropeném , Testes de Sensibilidade Microbiana/métodos , Tienamicinas/metabolismo , beta-Ciclodextrinas/metabolismo
12.
J Food Sci ; 80(6): S1377-82, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25982048

RESUMO

The potential of potato juice in relieving gastrointestinal disorders has already been proven. Work continues on implementation of this active component into products that are widely consumed. In this article, results of an attempt to fortify pasta with potato juice are presented and discussed. Fortification is performed using fresh and dried juice. The influence of the addition on culinary properties of the final product, such as cooking weight and cooking loss, as well as microstructure, color, texture, and consumer acceptance were evaluated. It was found that potato juice can be used for fortification of pasta both in its fresh and dried forms, however the effects on different responses depend on the potato juice form used. The addition of potato juice influenced the color of the product reducing its lightness and shifting color balances from green to red, yellow color saturation was decreased as well. Changes in color were more significant in the case of fresh juice addition. The firmness and microstructure of pasta was also influenced. The surface microstructure of pasta containing fresh potato juice was different from that of the other 2 products being a likely explanation of the lower cooking loss observed in its case. In contrast, the consistency of dough was strengthened by addition of dried potato juice. Principal components analysis indicated that the color change had the most pronounced effect on consumer acceptance. Other physicochemical changes were slightly less significant. Nevertheless, sensory evaluation proved that functional pasta produced with fresh potato juice finds consumer acceptance comparable with that of classic pasta.


Assuntos
Farinha/análise , Alimentos Fortificados/análise , Solanum tuberosum/química , Triticum/química , Adulto , Cor , Comportamento do Consumidor , Culinária/métodos , Fibras na Dieta/análise , Análise de Alimentos , Manipulação de Alimentos/métodos , Humanos , Microscopia Eletrônica de Varredura , Inquéritos e Questionários , Adulto Jovem
13.
Carbohydr Polym ; 117: 25-33, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25498605

RESUMO

Recent works have demonstrated that release behavior of bioactive compounds varies with the nature of the matrix regarding its chemical composition, morphology and surface properties. Starch matrices varying in amylose content (maize, sorghum, Hylon VII) or pure amylopectin ones (waxy maize, amaranth starch), containing theophylline (10 mg, 50 mg/0.5 g of starch), were obtained via high hydrostatic pressure treatment (650 MPa/9 min) and autoclaving (120 °C/20 min). Both the treatment used and drug dose affected the theophylline release profiles from the matrices studied. The profiles of amylopectin starch matrices satisfactorily fitted with selected mathematical models, indicating a controlled theophylline release. The principal component analysis confirmed substantial differences in drug release between the amylose and amylopectin matrices. The differences in matrix morphology, internal surface area and porosity (mesopore diameter, cumulative pore volume) between the matrices studied were found to be key factors affecting the theophylline dissolution.


Assuntos
Portadores de Fármacos/química , Liberação Controlada de Fármacos , Amido/química , Teofilina/química , Amaranthus/química , Pressão Hidrostática , Cinética , Análise de Componente Principal , Propriedades de Superfície , Temperatura , Zea mays/química
14.
Int J Biol Macromol ; 41(5): 534-47, 2007 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17719628

RESUMO

High-sensitivity differential scanning microcalorimetry (HSDSC), small-angle X-ray scattering (SAXS), light (LM) and scanning electronic (SEM) microscopy techniques were used to study the defectiveness of different supramolecular structures in starches extracted from 11 Thai cultivars of rice differing in level of amylose and amylopectin defects in starch crystalline lamellae. Despite differences in chain-length distribution of amylopectin macromolecules and amylose level in starches, the invariance in the sizes of crystalline lamellae, amylopectin clusters and granules was established. The combined analysis of DSC, SAXS, LM and SEM data for native starches, as well as the comparison of the thermodynamic data for native and annealed starches, allowed to determine the structure of defects and the localization of amylose chains in crystalline and amorphous lamellae, defectiveness of lamellae, clusters and granules. It was shown that amylose "tie chains", amylose-lipid complexes located in crystalline lamellae, defective ends of double helical chains dangling from crystallites inside amorphous lamellae ("dangling" chains), as well as amylopectin chains with DP 6-12 and 25-36 could be considered as defects. Their accumulation can lead to a formation of remnant granules. The changes observed in the structure of amylopectin chains and amylose content in starches are reflected in the interconnected alterations of structural organization on the lamellar, cluster and granule levels.


Assuntos
Oryza/química , Oryza/genética , Amido/química , Amido/genética , Varredura Diferencial de Calorimetria/métodos , China , Geografia , Microscopia Eletrônica de Varredura/métodos , Oryza/ultraestrutura , Amido/ultraestrutura , Termodinâmica , Difração de Raios X/métodos
15.
Carbohydr Res ; 340(1): 75-83, 2005 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-15620669

RESUMO

Structure and thermodynamic properties of native and annealed wheat starches with different amylose content (from 1.5% to 39.5%) have been studied by high-sensitivity differential scanning microcalorimetry (HSDSC), small-angle X-ray diffraction (SAXS), light (LM), and scanning electron microscopy (SEM). Starch morphology, the values of the melting cooperative unit, the thickness of crystalline lamellae and the size of amylopectin clusters as well as thermodynamic parameters characterizing surface of the face side in starch crystals were determined. Some suppositions based on different physical approaches are used for a discussion of the results concerning structural reorganization of starches on different levels of macromolecular organization.


Assuntos
Mutação/genética , Amido/química , Amido/ultraestrutura , Triticum/química , Triticum/genética , Amilose/análise , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Termodinâmica , Triticum/ultraestrutura , Difração de Raios X
16.
Carbohydr Res ; 339(16): 2683-91, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15519327

RESUMO

Small-angle X-ray scattering (SAXS) and scanning electron microscopy (SEM) were used to investigate the internal structure of wheat starch granules with different amylose content. Different approaches were used for treatment (interpretation) of SAXS data to assess the values of structural parameters of amylopectin clusters and the size of crystalline and amorphous lamella in different wheat starches. The average values of the semi-crystalline growth rings thickness in starches have been determined and the relationship between structural characteristics and thermodynamic melting parameters is discussed.


Assuntos
Amilopectina/química , Amilose/análise , Amido/química , Triticum/química , Amilopectina/ultraestrutura , Cristalização , Microscopia Eletrônica de Varredura , Amido/ultraestrutura , Termodinâmica , Triticum/ultraestrutura , Difração de Raios X
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