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1.
Molecules ; 27(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35268711

RESUMO

The article focuses on the optimization of the extraction process of biologically active compounds (BAC) from grape marc-a by-product of the wine industry. The influence of temperature, specifically 30 °C, 45 °C and 65 °C, and ethanol concentration in solutions, specifically 0-96% (v/v) on the extraction yield of polyphenols, flavonoids, tannins and anthocyanins, were investigated. The composition of individual polyphenols, anthocyanins and organic acids, antioxidant activity (DPPH and ABTS) and CIELab chromatic characteristics of the grape marc extracts (GME), were characterized. The microbiostatic and microbicidal effects in direct contact of GME with pathogenic microorganisms, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, were determined in vitro. The influence of extraction parameters on the total polyphenol content (TPC), total flavonoid content (TFC), tannin content (TC), total anthocyanin content (TAC) and their interdependencies were studied using information analysis. A mathematical model was developed on cubic spline functions. The analysis of individual compounds showed the presence of a wide range of flavonoids (procyanidin B2, procyanidin B1, hyperoside and quercetin), flavones (catechin), hydroxybenzoic acid derivatives (gallic, protocatechuic, p-hydroxybenzoic acids, m-hydroxybenzoic acid, syringic acid), hydroxycinic acid derivatives and ferulic acid methyl ester. The malvidol-3-glucoside was the main anthocyanin identified in the extract. A high amount of tartaric acid was also found. GME showed significant antimicrobial activity against Gram-positive bacteria and lower activity against Gram-negative bacteria.


Assuntos
Vitis , Antocianinas/química , Antioxidantes/química , Quimiometria , Flavonoides/análise , Flavonoides/farmacologia , Extratos Vegetais/química , Polifenóis/análise , Polifenóis/farmacologia , Vitis/química
2.
Molecules ; 26(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206313

RESUMO

Recent trends in the food industry combined with novel methods in agriculture could transform rowan into a valuable raw material with potential technological applications. Thus, the aim of this research was to investigate the content of bioactive compounds in its fruits and to assess the color and antioxidant stability of the extracts prepared from such fruits during various thermal treatments and at different pH and ionic strength values. Various spectrophotometric methods, HPLC, and capillary electrophoresis were used to quantify the concentrations of bioactive compounds-polyphenols, carotenoids, organic acids, and to assess antioxidant activity and color. The results show that rowan berries contain circa 1.34-1.47 g/100 g of polyphenols among which include catechin, epicatechin, ferulic acid methyl ester, procyanidin B1, etc.; ca 21.65 mg/100 g of carotenoids including zeaxanthin, ß-cryptoxanthin, all-trans-ß-carotene, and various organic acids such as malic, citric, and succinic, which result in a high antioxidant activity of 5.8 mmol TE/100 g. Results also showed that antioxidant activity exhibited high stability when the extract was subjected to various thermal treatments, pHs, and ionic strengths, while color was mainly impacted negatively when a temperature of 100 °C was employed. This data confirms the technological potential of this traditional, yet often overlooked species.


Assuntos
Antioxidantes/química , Frutas/química , Pigmentos Biológicos/química , Extratos Vegetais/química , Sorbus/química , Concentração de Íons de Hidrogênio , Concentração Osmolar , Polifenóis/química
3.
Sci Rep ; 10(1): 20920, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262393

RESUMO

Plasma activated water (PAW) can represent an alternative to chemical fertilizers in agriculture. The effects of PAW treatment applied in two concentrations (1.5 or 3.0 mg L-1 NO3-) on some morphological, physiological, biochemical parameters and yield of Lactuca sativa L. grown in two different pot volumes (400 or 3200 cm3) were investigated in this study. The results showed that both PAW concentrations did not influence the germination, once the process was initiated. Positive effects of the treatments were registered on the length of radicle and hypocotyls of lettuce at a concentration of 1.5 mg L-1 NO3- (PAW I), the chlorophyll content was significantly increased at a concentration of 3.0 mg L-1 NO3- (PAW II) and bigger pot volume, also the foliar weight and area. No significant differences between the treated and untreated plants were recorded for the root weight, leaf length and width. The dry weight was significantly higher for the lettuce treated with PAW I and II grown in big volume pots at 57 days after transplanting (DAT) and small volume pots at 64 DAT. The nitrites content of the lettuce grown in big pots was lower than of the lettuce grown in small pots, regardless of the PAW treatment. Contrary, the nitrates content was higher in the lettuce grown in big pots (up to 36.4 mg KNO3/g DW), compared to small pots (under 0.3 mg KNO3/g DW).


Assuntos
Lactuca/crescimento & desenvolvimento , Desenvolvimento Vegetal , Gases em Plasma/química , Água/farmacologia , Biomassa , Clorofila/metabolismo , Germinação/efeitos dos fármacos , Hipocótilo/efeitos dos fármacos , Hipocótilo/crescimento & desenvolvimento , Lactuca/efeitos dos fármacos , Nitratos/metabolismo , Fotossíntese/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Folhas de Planta/anatomia & histologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
4.
Molecules ; 25(23)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271766

RESUMO

The present study analyzes the complex of bioactive compounds from rose hips pulp powder (RHP) obtained after separating the seeds from Rosa canina L. in order to obtain the oil. The extract prepared from RHP was characterized in terms of the total content of polyphenols, flavonoids, cinnamic acids, flavonols, carotenoids, but also the content of individual polyphenols and carotenoids, antioxidant activity, and CIELab color parameters. The effects of some salts, potentially present in foods, and pH variations were examined to predict possible interactions that could occur when adding rosehip pulp as a food component. The results turned out to be a high content of polyphenols, carotenoids and antioxidant activity. The main phenolic components are procyanidin B1, chlorogenic acid, epicatechin, procyanidin B2, gallic acid, salicylic acid, and catechin. The carotenoid complex includes all-trans-ß-carotene, all-trans-lycopene, zeaxanthin, α-cryptoxanthin, ß-cryptoxanthin, rubixanthin, cis-ß-carotene, cis-γ-carotene and cis-lycopene. The addition of CaCl2 and NaCl to the RHP extract reduced the antioxidant activity and the strong acidic environment (pH to 2.5) decreased the antioxidant activity by 29%. The addition of rose hip powder to gingerbread has improved its general characteristics, and increased its antioxidant activity and microbiological stability, the effects of 4% RHP being the most important.


Assuntos
Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Pão/análise , Carotenoides/farmacologia , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Rosales/química , Zingiber officinale/química , Antioxidantes/isolamento & purificação , Carotenoides/isolamento & purificação , Flavonoides/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Polifenóis/isolamento & purificação
5.
J Food Sci Technol ; 57(12): 4383-4394, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33087952

RESUMO

Matching the general trend of replacing synthetic additives with healthier natural products, the present research studies the effects of different concentrations of chokeberry extract which substitute carmoisine dye in jelly candies. Also, the colour and antioxidant properties of the aforementioned extract and their changes at various pH and in presence of different mineral salts from foods are analysed. The phenolic content of the extract was determined using HPLC and spectrophotometric methods. A high concentration of polyphenols was found in the chokeberry extract, of which around 97% were flavonoids. Catechin, epicatechin, ferulic acid and its methyl esther, protocatechuic, gallic and para-hydroxybenzoic acids were the major phenolics identified in the extract. The total antioxidant activity decreased in acidic media, while close-to-neutral and alkaline pH values did not exhibit any effect on this parameter. Furthermore, the green/red colour parameter, the chroma and the hue angle were enhanced in the most acidic media (pH 2.3 and 3.5). From the studied salts, CaCl2 and KNO3 had the most significant effects on colour. The chokeberry extract proved to be suitable as replacement of carmoisine dye in jelly candies, as the physicochemical and microbiological properties comply with the regulated requirements. More than that, the extract improved the antioxidant and sensory properties of jellies in all studied concentrations and the best total sensory score was obtained for 1.5% extract. After 5 and 50 days of storage, the microbiological properties were improved in candies prepared with aronia extracts compared to carmoisine, as the total viable count registered important diminutions.

6.
J Food Sci Technol ; 57(2): 628-637, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32116372

RESUMO

The aim of this study was to evaluate the physico-chemical, microbiological, sensory properties and antioxidant activity of the functional cream cheese prepared with lipophilic extracts of sea buckthorn (Hippophae rhamnoides L.). The first step of the research consisted of an evaluation of the physico-chemical characteristics and the antioxidant capacity of the sea buckthorn lipophilic extracts. The sea buckthorn extracts had a significant antioxidant capacity (67.04 ± 2.67%), a content of total carotenoids of 8.27 ± 0.01 mg L-1 and a content of total polyphenols of 1842.86 ± 1.41 mg/100 g dry vegetal material. The addition of the sea buckthorn extracts did not negatively affect the fresh cream cheese's sensory characteristics. The addition of sea buckthorn extracts to the cream cheese resulted in an increase of antiradical activity and dry matter content, a decrease in acidity and higher growth inhibitition of germs.

7.
Molecules ; 25(6)2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32168868

RESUMO

Sea buckthorn (Hippophae rhamnoides) berries are well known for their content in bioactive compounds, high acidity, bright yellow color, pleasant taste and odor, thus their addition in a basic food such as bread could be an opportunity for modern food producers. The aim of the present research was to investigate the characteristics and the effects of the berry' flour added in wheat bread (in concentration of 1%, 3% and 5%) on sensory, physicochemical and antioxidant properties, and also bread shelf life. Berry flour contained total polyphenols-1467 mg gallic acid equivalents (GAE)/100 g, of which flavonoids-555 mg GAE/100 g, cinnamic acids-425 mg caffeic acid equivalents (CAE)/100 g, flavonols-668 mg quercetin equivalents (QE)/100 g. The main identified phenolics were catechin, hyperoside, chlorogenic acid, cis- and trans-resveratrol, ferulic and protocatechuic acids, procyanidins B1 and B2, epicatechin, gallic acid, quercetin, p- and m-hydroxybenzoic acids. The antioxidant activity was 7.64 mmol TE/100 g, and carotenoids content 34.93 ± 1.3 mg/100 g. The addition of berry flour increased the antioxidant activity of bread and the shelf life up to 120 h by inhibiting the development of rope spoilage. The obtained results recommend the addition of 1% Hippophae rhamnoides berry flour in wheat bread, in order to obtain a product enriched in health-promoting biomolecules, with better sensorial and antioxidant properties and longer shelf life.


Assuntos
Antioxidantes/isolamento & purificação , Pão/análise , Flavonoides/isolamento & purificação , Flavonóis/isolamento & purificação , Farinha/análise , Hippophae/química , Polifenóis/isolamento & purificação , Antioxidantes/classificação , Ácidos Cafeicos/isolamento & purificação , Carotenoides/classificação , Carotenoides/isolamento & purificação , Cinamatos/isolamento & purificação , Flavonoides/classificação , Flavonóis/classificação , Armazenamento de Alimentos , Tecnologia de Alimentos/métodos , Frutas/química , Ácido Gálico/isolamento & purificação , Humanos , Polifenóis/classificação , Quercetina/isolamento & purificação
8.
J Food Biochem ; 43(4): e12788, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31353573

RESUMO

The aim of present study was to investigate the influences of pH and several salts on the antioxidant activity and color of an ethanolic grape marc extract. Furthermore, the phenolic content of the extract was analyzed using HPLC and spectrophotometric methods while the total antioxidant activity was assessed by the reaction with ABTS radical. Gallic acid, procyanidins B1, B2, polydatin, catechin, epicatechin, hyperoside, ferulic, chlorogenic, and salicylic acids were among the main identified polyphenols. Different pH values had slight influence on the antioxidant activity, the highest value being determined for pH 3.7. The redness, chroma, and hue were significantly enhanced at pH 3.7 and 2.6. The chromaticity decreased at pH = 5.5 and pH = 7.4, so the extract should be used with care in products with such media. The presence of salts did not noticeably affect the antioxidant activity, except the higher concentrations of CaCl2 , which decreased the antioxidant activity but enhanced the color intensity. PRACTICAL APPLICATION: The data presented in this paper could be used for the development of a new food dye with antioxidant properties of natural origin. The optimal medium conditions (i.e., pH and ionic strength) for the use of an ethanolic red grape marc extract have been identified. The information could be used in product development and product formulation, especially when functional foodstuffs are envisaged. Consequently, this paper would be of significant interest for food chemists, food technologists, food manufacturers, and especially manufacturers of food dyes and all those using natural substances in their production process.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Vitis/química , Fracionamento Químico , Cor , Frutas/química , Concentração de Íons de Hidrogênio , Concentração Osmolar , Resíduos/análise
9.
Food Chem ; 275: 539-548, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724231

RESUMO

Red cabbage waste is a valuable source of anthocyanins which may be used as natural food dye. Excepting the colouring agents, food/beverage contains compounds from the matrix or other additives/ingredients. Present study reveals the influences of nineteen food additives/ingredients on the stability, colour parameters and radical scavenging activity during 20 weeks of storage of red cabbage waste hydroethanolic extract (initial pH = 6.31) under aerobic atmosphere, in the dark, at 4 °C. At studied concentration (0.2%), most important changes were produced by tartaric and citric acids: decrease of monomeric anthocyanins content, lightness, radical scavenging activity, and increase of polymeric colour, browning and degradation indices, chroma and red colour parameter, absolute value of blue colour parameter and hue angle, inducing very important overall colourimetric differences. Similar influences, but much attenuated, proved ascorbic and benzoic acids. During storage, the untreated extracts revealed a very high stability, and also mostly of treated extracts (especially with sugars).


Assuntos
Brassica/química , Etanol/química , Aditivos Alimentares/química , Extratos Vegetais/química , Cor , Estabilidade de Medicamentos
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