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1.
Molecules ; 28(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37894486

RESUMO

Dark chocolate dragée confectionary was made with BRS Clara raisins pre-treated with extra virgin olive oil (EVOO). The evaluation of the changes in the phenolic composition (flavonols, hydrocinnamic acid derivatives (HCADs), stilbenes and flavan-3-ol monomers, dimers, and proanthocyanidins (PAs)) resulting from the covering process showed that the chocolate coating was responsible for an increase in the concentrations of flavan-3-ols and PAs when compared to just the raisins. For the flavonols and HCADs, a reduction in the total concentration of compounds was observed when comparing the dragées to the raisins. Furthermore, there was a strong influence of chocolate in the qualitative profile with the emergence of new compounds (quercetin-3-pentoside, kampfterol-3-rutinoside, p-coumaric acid, and caffeoyl-aspartate). The combination of these ingredients (raisins and chocolate) resulted in a dark chocolate coated raisin (DC) with good sensory acceptance and a more complex phenolic composition that may positively contribute to its functional quality.


Assuntos
Cacau , Chocolate , Proantocianidinas , Vitis , Fenóis/análise , Flavonóis/análise , Proantocianidinas/análise , Cromatografia Líquida de Alta Pressão/métodos
2.
Photochem Photobiol Sci ; 22(3): 669-686, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36417143

RESUMO

The mycelial biomass of basidiomycetes is a promising source of compounds and represents an alternative for industrial and biotechnological applications. Fungi use light as information and hold photoresponse mechanisms, in which sensors respond to light wavelengths and regulate various biological processes. Therefore, this study aimed to investigate the effects of blue, green, and red lights on the growth, chemical composition, and antioxidant and antimicrobial activity of Lentinus crinitus mycelial biomass. The chemical composition of the mycelial biomass was determined by chromatographic methods, antioxidant activity was analyzed by in vitro assays, and antimicrobial activity was investigated by the microdilution assay. The highest mycelial biomass yield was observed under blue-light cultivation. Many primordia arose under blue or green light, whereas the stroma was formed under red light. The presence of light altered the primary fungal metabolism, increasing the carbohydrate, tocopherol, fatty acid, and soluble sugar contents, mostly mannitol, and reducing the protein and organic acid concentrations. Cultivation under red light increased the phenol concentration. In contrast, cultivation under blue and green lights decreased phenol concentration. Benzoic and gallic acids were the main phenolic acids in the hydroalcoholic extracts, and the latter acids increased in all cultures under light, especially red light. Mycelial biomass cultivated under red light showed the highest antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ferric reducing antioxidant power (FRAP) method showed that all light wavelengths increased the antioxidant activity of mycelial biomass, with the highest value under red light. Moreover, the ß-carotene/linoleic acid co-oxidation (BCLA) assay demonstrated that the antioxidant activity was affected by light cultivation. Mycelial biomass grown under all conditions exhibited antibacterial and antifungal activities. Thus, mycelial biomass cultivation of L. crinitus under light conditions may be a promising strategy for controlling the mycelial chemical composition and biomass yield.


Assuntos
Anti-Infecciosos , Basidiomycota , Lentinula , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Biomassa , Lentinula/metabolismo , Basidiomycota/metabolismo , Fenóis/metabolismo
3.
J Sci Food Agric ; 100(2): 836-845, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31646641

RESUMO

BACKGROUND: A classical postulate of viticulture declares that small grape berries produce the best red wines. The popularity of this postulate among winemakers leads them to consider berry size at harvest as a tool to measure the grape's potential to obtain great red wines. To address this issue, two vineyards from the same cultivar and subjected to the same physiological conditions during growing were selected for their difference in average grape berry size at harvest. Grapes from both origins were characterized and used for red winemaking by the same way. Release of volatile compounds and phenolic compounds during the alcoholic fermentation was monitored, and the finished wines were chemically characterized. RESULTS: Larger grapes have a lower theoretical surface-to-volume ratio but have thicker skins and a greater proportion of skins (m/m). Wines made from grapes with a greater proportion of skins contain higher amounts of phenolic compounds, terpenes, volatile acids, acetate esters and polysaccharides. CONCLUSION: According to the results, it seems that grape skin extraction is more related to skin proportion than to berry size. Thus not always smaller grapes produce darker red wines. © 2019 Society of Chemical Industry.


Assuntos
Frutas/química , Vitis/crescimento & desenvolvimento , Vinho/análise , Ésteres , Manipulação de Alimentos , Frutas/crescimento & desenvolvimento , Fenóis/química , Terpenos/química , Vitis/química , Compostos Orgânicos Voláteis/química
4.
Food Chem ; 294: 302-308, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126467

RESUMO

Pereskia aculeata Miller, known worldwide as ora-pro-nobis, is a highly nutritive species of the Cactaceae family from the Brazilian Atlantic Forest. In this work, we report inedited information on the phenolic profile of P. aculeata leaves, besides a broad study of their antioxidant potential using a set of five different methods. A total of ten phenolic compounds were identified, such as two phenolic acids (caffeic acid derivatives) and eight flavonoids (quercetin, kaempferol and isorhamnetin glycoside derivatives). Caftaric acid was the extract's major phenolic constituent, accounting for more than 49% of the phenolic content, followed by quercetin-3-O-rutinoside (14.99%) and isorhamnetin-O-pentoside-O-rutinoside (9.56%). Overall, the ora-pro-nobis leaf extract showed relevant values of antioxidant capacity, with higher activities than the Trolox in the DPPH and ABTS trials. The antimicrobial activity exhibited by the extract against both Gram-positive and Gram-negative bacteria suggests the presence of a broad spectrum of phytochemicals with antibiotic activity.


Assuntos
Cactaceae/química , Compostos Fitoquímicos/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/química , Brasil , Cactaceae/metabolismo , Células Cultivadas , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Florestas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo
5.
Food Res Int ; 116: 190-199, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30716936

RESUMO

The grape is an important fruit regarding economic and health benefit parameters, because of its large consumption around the world and their bioactive phenolic compounds. The drying process of BRS Morena grapes, whether pre-treated or not with olive oil for producing raisins, resulted in qualitative and quantitative changes in their phenolic composition (anthocyanins, flavonols, stilbenes, hydroxycinammic acid derivatives, flavan-3-ols and proanthocyanidins). The raisins with the pre-treatment preserved more anthocyanins and proanthocyanidins than the raisins not pre-treated. Moreover, the total dehydration time accelerated by approximately 40% in the raisins pre-treated. Therefore, the production of raisins of BRS Morena grapes pre-treated with olive oil as a natural surfactant constitutes an interesting process from both the industrial and health points of view, because of the remarkable reduction in the processing time and the preservation of high concentrations of flavonoids, which have important claims to health benefits from biological activities.


Assuntos
Dessecação , Frutas/química , Fenóis/análise , Vitis/química , Antocianinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonóis/análise , Extratos Vegetais/química , Proantocianidinas/análise , Estilbenos/análise
6.
Food Chem ; 269: 103-110, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100411

RESUMO

This work aimed to investigate the evolution of phenolic compounds and elements during the aging of Malbec red wines from different regions of Mendoza (Argentina) and California (United States). The profiles of low molecular weight polyphenols and anthocyanins were analyzed using high-performance liquid chromatography with a diode-array detector (HPLC-DAD), and the elemental composition using microwave plasma-Atomic emission spectrometry (MP-AES). Through uni- and multivariate statistical analyses, the effects of aging time and region on wine were investigated. It was observed that aging time was a significant factor that affected the phenolic compound profile in the studied Malbec wines studied and that after five years of aging, the wines could be differentiated according to region. The results of this study may impact decisions made regarding the storage of Malbec wines in the future.


Assuntos
Antocianinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Fenóis/análise , Vitis/química , Vinho/análise , Argentina , California
7.
Food Res Int ; 106: 729-735, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579981

RESUMO

This paper reports on a study of chemical characterization and colour parameters of cv. Carignan red wines from six locations and two production years of the Chilean Maule valley. The chemical study was performed on polyphenolic composition (benzoic acids, hydroxycinnamic acid derivatives, stilbenes, flavan-3-ols, flavonols and anthocyanins) and several fractions of proanthocyanidins and polysaccharides. Results revealed that although significantly (p < 0.05) different content of anthocyanins were observed according to the production year, it could be possible to establish fingerprints of the different locations of the Maule valley wines. Thus, wines from zones closer to the Andes Mountains had higher content of procyanidin B3 (Caliboro), polysaccharides and cis-resveratrol-glucoside (Loncomilla and Melozal), whereas the proximity to the Pacific Ocean provoked a unifying effect in chemical and colorimetric terms (Cauquenes, Sauzal and Huerta del Maule).


Assuntos
Análise de Alimentos/métodos , Frutas/química , Polifenóis/análise , Polissacarídeos/análise , Vitis/química , Fracionamento Químico , Chile , Clima , Cor , Colorimetria , Frutas/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento
8.
Molecules ; 22(9)2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28926992

RESUMO

The native tree Geoffroea decorticans (chañar) grows in the arid lands of northern Chile. It has been used as a food plant since prehistoric times. Phenolic-enriched extracts (PEEs) of Chilean chañar fruits were assessed for their chemical composition, antioxidant properties and inhibition of pro-inflammatory and metabolic syndrome-associated enzymes. Phenolic profiles were determined by HPLC-DAD-MS/MS. The PEEs of G. decorticans showed a strong effect towards the enzymes COX-1/COX-2, with inhibition percentages ranging from inactive to 92.1% and inactive to 76.0% at 50 µg PEE/mL, respectively. The IC50 values of the PEEs towards lipoxygenase and phospholipase A2 inhibitory activity were between 43.6-96.8 and 98.9-156.0 µg PEE/mL, respectively. Samples inhibited α-glucosidase (IC50 0.8-7.3 µg PEE/mL) and lipase (9.9 to >100 µg PEE/mL). However, samples did not inhibit α-amylase. The HPLC-DAD-MS analysis of the PEEs allowed the tentative identification of 53 compounds, mainly flavonol glycosides and procyanidins. The procyanidin content of the Chilean G. decorticans pulp was positively correlated with the antioxidant activity and the inhibition of the enzyme α-glucosidase. These results indicate that the Chilean chañar fruit contains bioactive polyphenols with functional properties.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/química , Fabaceae/química , Fenóis/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Biflavonoides/química , Catequina/química , Sobrevivência Celular/efeitos dos fármacos , Chile , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Flavonóis/química , Frutas/química , Humanos , Lipoxigenase/metabolismo , Síndrome Metabólica/enzimologia , Fenóis/isolamento & purificação , Fenóis/farmacologia , Fosfolipases/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Proantocianidinas/química , alfa-Glucosidases/metabolismo
9.
Antioxidants (Basel) ; 4(2): 281-92, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-26783705

RESUMO

The antioxidant activity and phenolic composition of six in vitro cultured blueberry seedlings were determined. Extracts were prepared in 85% ethanol from 30 days old in vitro cultured plants and used to evaluate the antioxidant capacities that included Ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazin (DPPH•) scavenging ability, total polyphenols (TP) and the partial phenolic composition performed by high performance liquid chromatography with diode array detector (HPLC-DAD), liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS (ESI-QqQ)). All ethanolic extracts from in vitro blueberry cultivars displayed antioxidant activity, with Legacy, Elliott and Bluegold cultivars being the most active. In addition, we observed a positive correlation between phenolic content and antioxidant activity. Our results suggest that the antioxidant activity of the extracts is related to the content of chlorogenic acid myricetin, syringic acid and rutin, and tissue culture of blueberry seedlings is a good tool to obtain antioxidant extracts with reproducible profile of compounds.

10.
São Paulo; s.n; 2011. 140 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-640014

RESUMO

O vinho tinto é rico em compostos fenólicos com atividade antioxidante, capazes de inativar espécies reativas de oxigênio, minimizando danos celulares oriundos do estresse oxidativo, proporcionando uma redução de risco para doenças crônicas não transmissíveis. Assim, os objetivos desta pesquisa foram identificar associações entre a atividade antioxidante in vitro e fatores relacionados ao tipo de uva, região de produção, perfil sensorial, safra, valor comercial e concentração de compostos fenólicos de vinhos tintos produzidos no Brasil, Chile e Argentina. Inicialmente, os vinhos brasileiros (n=29) foram avaliados em relação à atividade antioxidante (ORAC e DPPH), cor instrumental e compostos fenólicos majoritários, no intuito de verificar qual classe de fenólicos estaria associada com a atividade antioxidante. Verificou-se que tanto os compostos fenólicos totais como os flavonóides totais, com destaque aos flavonóides não-antociânicos, se associaram significativamente (p<0,05) com a atividade antioxidante. Em um segundo passo, as características sensoriais, a cor, o valor comercial e a atividade antioxidante das 80 amostras de vinhos Sul-Americanos, distribuídas em Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), e vinhos de uvas americanas (Vitis labrusca) (n=7) foram avaliados usando estatística multivariada, objetivando-se verificar se a qualidade sensorial das amostras estaria associada com o valor comercial, cor, e à atividade antioxidante. De uma forma geral, os vinhos chilenos e argentinos apresentaram maior atividade antioxidante, valor comercial, intensidade de odor, qualidade sensorial, índice de acidez e taninos, ao passo que os vinhos brasileiros obtiveram os menores valores para os atributos sensoriais. Os vinhos de uvas americanas apresentaram menores valores para todas as variáveis. As varietais Syrah, Malbec e Cabernet Sauvignon apresentaram maior capacidade antioxidante e melhores características ...


Red wine is rich in phenolic compounds with antioxidant activity, being able to buffer reactive oxygen species, thus decreasing the risk of non-transmissible chronic diseases. In this regard, the objectives of this research aimed at identifying associations between the in vitro antioxidant activity and factors related to grape varietal, region of production, sensory profile, vintage, color, commercial value, and concentration of phenolic compounds of red wines produced in Brazil, Chile, and Argentina. Initially, the Brazilian red wines (n = 29) were assessed in relation to antioxidant activity, instrumental color, and major phenolic compounds with the objective to verify which phenolic class was associated with the antioxidant activity. Both the total phenolic compounds and total flavonoids, with special attention to non-anthocyanin flavonoids, were significantly associated with the antioxidant activity. In a second step, the sensory characteristics, color, commercial value, and antioxidant activity of the 80 red wine samples, which were distributed in Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), and table wines (Vitis labrusca) (n=7) were evaluated using multivariate statistical techniques, with the aim to verify how the overall perception of quality of wines was related to commercial value, color and antioxidant activity. In a general way, te Chilean and Argentinean red wines displayed a higher antioxidant activity, commercial value, intensity of odors, sensory perception of quality, acidity level, and tannin level, whereas the Brazilian samples obtained the lowest values for the sensory attributes. The table wines presented the lowest values for all response variables. Syrah, Malbec and Cabernet Sauvignon varietals presented the highest antioxidant activity and most favorable sensory features, and this result was independent of wine's vintage and origin. As a last step, the wines produced with V. vinifera grapes …


Assuntos
Antioxidantes/análise , Antioxidantes/classificação , Técnicas In Vitro , América do Sul , Relação Estrutura-Atividade , Paladar , Vinho/análise , Vinho/classificação , Compostos Fenólicos/análise , Compostos Fenólicos/estatística & dados numéricos , Análise Multivariada , Radicais Livres/análise , Limiar Gustativo
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