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1.
Food Chem ; 306: 125611, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606631

RESUMO

Aromatic secondary metabolites are closely related to quality attributes of postharvest fruit. In the present study, 20% CO2 was applied to strawberry fruit to investigate the regulation of elevated CO2 on aromatic secondary metabolites. The results showed that elevated CO2 delayed accumulations of anthocyanins, eugenol and lignin. Phenylalanine and tyrosine, the precursors of the above secondary metabolites, were 18.90% and 35.61%, respectively, lower in CO2-treated fruit compared with the control on day 6. Furthermore, enzyme activities and transcriptional profiles analysis showed pentose phosphate pathway and glycolysis were activated by elevated CO2 whereas the aromatic amino acids (AAAs) pathway was inhibited. These results indicated that elevated CO2 restricted carbon flux into aromatic secondary metabolism by inhibiting the AAAs pathway, leading to the decrease of phenylalanine and tyrosine, and thus, delayed the accumulation of aromatic secondary metabolites. In addition, the effect of elevated CO2 was eliminated after transferred CO2-treated fruit to air.


Assuntos
Fragaria/metabolismo , Antocianinas/análise , Antocianinas/metabolismo , Dióxido de Carbono/química , Eugenol/análise , Eugenol/metabolismo , Fragaria/química , Frutas/química , Frutas/metabolismo , Lignina/análise , Lignina/metabolismo
2.
Food Chem ; 307: 125518, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31644976

RESUMO

The Greek vineyard is home to many minor, indigenous grape cultivar whose diverse polyphenolic content has remained largely unexploited. The study aimed at assaying and assessing the polyphenolic content and antioxidant capacity of: (a) five obscure cultivars; (b) Six biotypes of cultivar 'Liatiko'; (c) Five prominent cultivars; and (d) three French varieties included for comparison reasons. Results revealed all samples exhibiting high polyphenol content and antioxidant capacity levels. 'Vertzami' recorded the highest concentrations in berry skins total anthocyanins, flavanols, flavonols, antioxidant capacity. 'Mandilaria' scored the highest value in seed total flavanols compared to all biotypes and cultivars. All 'Liatiko' biotypes scored the highest concentrations in seed total flavonoids and flavonols. 'Liatiko' and its biotypes exhibited different polyphenolic profiles between them. Owing to the climate change, those indigenous varieties' substantial polyphenol amounts, and the differences between biotypes, will allow viticulturists to select the varieties/biotypes most appropriate for obtaining higher quality products.


Assuntos
Antioxidantes/química , Polifenóis/química , Vitis/química , Antocianinas/análise , Mudança Climática , Flavonoides/análise , Flavonóis/análise , Frutas/química , Frutas/metabolismo , Grécia , Polifenóis/análise , Sementes/química , Sementes/metabolismo , Vitis/metabolismo
3.
Food Chem ; 305: 125430, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518840

RESUMO

The distributions of total soluble solids, pectins, the sum of polyphenolic and terpenoid compounds as well as the antioxidative potency of fruit and their parts, such as peel, flesh, and seeds of Saskatoon berry genotypes are presented in this work. The contents of individual bioactive compounds of in this fruit fraction of Saskatoon berry cultivars and cultivation clones significantly depended on berry genotype and compounds distribution within particular parts of the fruit. The fruit peel contained mainly anthocyanins, polymerized compounds, hydroxycinnamic acids, triterpenoids, and tetraterpenids, as well as exhibited antioxidant activity. The major compounds identified in the fruit flesh included soluble solids, ash, flavonols. In turn, polymeric procyanidins was determined in the seeds of fruit. Individual parts of Saskatoon berry fruit contained many health-promoting constituents and could be deemed attractive materials for the production of functional foods or dietary supplements.


Assuntos
Antioxidantes/análise , Frutas/química , Compostos Fitoquímicos/análise , Rosaceae/química , Antocianinas/análise , Ácidos Cumáricos/análise , Flavonóis/análise , Proantocianidinas/análise , Sementes/química , Terpenos/análise
4.
J Sci Food Agric ; 100(1): 145-153, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31471914

RESUMO

BACKGROUND: Previous reports have addressed the effectiveness of postharvest methyl jasmonate (MeJA) treatments on maintaining quality properties of pomegranate fruit during storage. However, there is no literature regarding the effects of preharvest MeJA treatments on pomegranate 'Mollar de Elche' crop yield, fruit ripening, quality attributes and bioactive compounds content (at harvest or after long-term storage), which were evaluated in this research. RESULTS: Preharvest MeJA treatments (1, 5, and 10 mmol L-1 ) increased pomegranate crop yield. MeJA at 1 and 5 mmol L-1 accelerated the on-tree ripening process, while it was delayed with 10 mmol L-1 . Losses in fruit weight, firmness and organic acids during storage at 10 °C were delayed in MeJA treated fruit, leading to quality maintenance. In addition, MeJA treatments improved arils colour due to increased concentration of total and individual anthocyanins, at harvest and during storage. Total phenolic and ascorbic acid contents and total antioxidant activity [hydrophilic (H-TAA) and lipophilic (L-TAA) fractions] were also higher in arils from treated pomegranate fruits than in controls. CONCLUSION: Preharvest treatments with MeJA could be a promising tool to improve pomegranate crop yield, fruit quality and its content in bioactive compounds at harvest and during storage. The higher effects were obtained with MeJA at 5 mmol L-1 dose, which could be the selected treatment for practical application purposes. © 2019 Society of Chemical Industry.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/química , Lythraceae/efeitos dos fármacos , Oxilipinas/farmacologia , Extratos Vegetais/análise , Antocianinas/análise , Antioxidantes/análise , Ácido Ascórbico/análise , Cor , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Lythraceae/química , Fenóis/análise
5.
Food Chem ; 305: 125438, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31494498

RESUMO

Fifteen vitisin A-type pyranoanthocyanins (vAPs) were determined in bilberry wines fermented with Saccharomyces cerevisiae and Schizosaccharomyces pombe by HPLC-DAD and UPLC-DAD-ESI-MS/MS. The fermentation involving S. pombe enhanced the production of vAPs compared to the fermentation with pure S. cerevisiae. The formation of vAPs correlated significantly with the decrease in the content of monomeric anthocyanins and pyruvic acid during 12 months of aging. vAPs were more stable than their corresponding monomeric anthocyanins. Methylation in the B-ring and glycosylation with galactose and arabinose further improved the stability of vAPs. Aging for 12 months led to depletion of pyruvic acid and reduction of over 50% of monomeric anthocyanins. The content of vAPs increased by 26-54% during the first six months of aging, followed by a 2.2-10.2% reduction over the following six months. More residual pyruvic acid in S. pombe wines after fermentation consequently enhanced the generation of vAPs during aging.


Assuntos
Antocianinas/análise , Sucos de Frutas e Vegetais/análise , Schizosaccharomyces/fisiologia , Vaccinium myrtillus/química , Benzofuranos/química , Reatores Biológicos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Fenóis/química , Ácido Pirúvico/metabolismo , Fatores de Tempo , Vaccinium myrtillus/metabolismo
6.
Food Chem ; 306: 125644, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31610329

RESUMO

Far infrared radiation (FIR) and hot air drying (HA) were applied to unpolished and polished pigmented rice varieties. Ferulic acid is a major phenolic acid in pigmented rice, being three-fold greater in bound form than in soluble form. Overall, FIR increased total phenolic and flavonoid contents, anthocyanin, tocopherols as well as antioxidant capacity, whereas the opposite results were observed for HA in all samples. Gallic, and ferulic acids were significantly (p < 0.05) increased in FIR dried samples. Quercetin content was significantly increased in unpolished rice dried by FIR and HA. Cyanidin-3-glucoside was greatly increased by FIR. Amino acids were decreased less by HA than did FIR. Our findings suggest that HA and FIR may have a significant effect on the internal structure of the grain, which may increase the yield of extraction of some components, including the bioactives.


Assuntos
Aminoácidos/química , Oryza/química , Ar , Aminoácidos/metabolismo , Antocianinas/análise , Antioxidantes/análise , Ácidos Cumáricos/análise , Grão Comestível/química , Hidroxibenzoatos/análise , Raios Infravermelhos
7.
Food Chem ; 301: 125170, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398671

RESUMO

The technological and polyphenolic parameters of grapes for juice processing obtained from successive harvests were studied in semi-arid tropical viticulture. Red grapes "BRS Violeta" and "Isabel Precoce" were harvested during the same year and analyzed based on a multivariate approach that included climatic variations. The grapes were marked by variations in flavonoid compounds, particularly anthocyanins. Temperature, global radiation, air velocity and evapotranspiration rates were associated with higher accumulation of bioactive polyphenols in grape berries and juices. The temperatures in February were associated with higher antioxidant activity in grape peels, while the highest thermal amplitude in August and November favored the accumulation of anthocyanins up to 564 mg kg-1. Flavanols and procyanidin compounds were more abundant in seeds when the maximum thermal amplitude was 13.8 °C. The climatic data together with the polyphenolic results point out useful information about appropriate periods for harvesting grapes with high phenolic content in tropical areas.


Assuntos
Agricultura/métodos , Sucos de Frutas e Vegetais/análise , Frutas/química , Vitis/química , Antocianinas/análise , Biflavonoides/análise , Brasil , Catequina/análise , Flavonoides/análise , Qualidade dos Alimentos , Fenóis/análise , Polifenóis/análise , Proantocianidinas/análise , Clima Tropical
8.
Food Chem ; 301: 125295, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387038

RESUMO

Raspberry fruits are a perfect source of polyphenols, including flavonols, anthocyanins. Some experiments have indicated that organic fruits contain more bioactive compounds than conventional fruits. The aim of this study was therefore to analyse and compare the concentration of bioactive compounds in organic vs. conventional raspberries and to determine the effects of harvest time and cultivar. Three cultivars of raspberry ('Laszka', 'Glen Ample' and 'Glen Fine') that were harvested in summer and one 'Polka' cv. that was harvested in autumn time from organic and conventional cultivation methods were used in the experiment. The contents of dry matter and polyphenols in the fruits were determined. The organic samples contained significantly more dry matter, phenolic acid and flavonoids, including myrycetin, quercetin, luteolin and quercetin-3-O-rutinoside. Harvest time was an important factor in raspberry fruit quality.


Assuntos
Agricultura/métodos , Polifenóis/análise , Rubus/química , Antocianinas/análise , Fazendas , Flavonoides/análise , Frutas/química , Agricultura Orgânica/métodos , Fatores de Tempo
9.
Food Chem ; 301: 125289, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387047

RESUMO

Acylated anthocyanins, such as those found in red cabbage, are more heat-, light-, and alkaline pH-stable than non-acylated anthocyanins, making them attractive for a variety of commercial applications. A UPLC-DAD-MSE method with an optimized chromatographic strategy was used to identify 29 red cabbage anthocyanins, predominantly acylated and glucosylated cyanidin derivatives. Anthocyanin profiles of 27 red cabbage genotypes harvested in consecutive growing seasons were measured and assessed for variation. Three unique anthocyanin profile fingerprints were identified through hierarchical clustering analysis. PCA analysis identified anthocyanin accumulation traits and genotypes with high diversity which can be utilized in future investigations into the genetic and molecular basis for anthocyanin production, acylation, and diversity.


Assuntos
Antocianinas/análise , Brassica/química , Brassica/genética , Melhoramento Vegetal , Polimorfismo Genético , Estações do Ano , Acilação , Antocianinas/química , Brassica/metabolismo , Cromatografia Líquida de Alta Pressão , Genótipo , Espectrometria de Massas
10.
Food Chem ; 301: 125304, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394335

RESUMO

Black rice is a variety of pigmented rice. It contains numerous nutritional and bioactive components, including essential amino acids, functional lipids, dietary fibre, vitamins, minerals, anthocyanins, phenolic compounds, γ-oryzanols, tocopherols, tocotrienols, phytosterols and phytic acid. There have been several studies of black rice due to its alleged beneficial health effects when consumed regularly. This review focuses on the historical aspects, chemical composition, and nutritional and functional properties of black rice. Furthermore, a discussion of the development of new foods and beverages with applications and processing technologies designed to improve their quality attributes. The nutritional value of black rice means that it has the potential to be used in the production of healthy foods and beverages, such as functional products and gluten-free cereals, thereby providing extra health benefits to consumers.


Assuntos
Indústria de Processamento de Alimentos/métodos , Valor Nutritivo , Oryza/química , Oryza/fisiologia , Antocianinas/análise , Fibras na Dieta/análise , Minerais/análise , Fenóis/análise , Tocoferóis/análise , Tocotrienóis/análise
11.
Plant Physiol Biochem ; 142: 332-341, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31377482

RESUMO

Anthocyanins are a class of compounds that are widespread in plants, where they provide protection against stresses, and are also beneficial to human health as dietary components. Melatonin application is known to affect anthocyanin production, but the relationship between anthocyanin and melatonin is still unclear. In this study, we analyzed anthocyanin contents and the expression levels of anthocyanin biosynthetic and regulatory genes in tissue cultured plantlets of two Malus crabapple cultivars following various exogenous melatonin treatments under light and dark conditions. The application of exogenous melatonin not only promoted anthocyanin accumulation in leaves, but also increased the contents of flavonols and proanthocyanins (PAs), via a process that was not dependent on light. Quantitative real time PCR (qRT-PCR) analyses indicated that the expression of flavonoid biosynthetic genes, flavonoid related transcription factors and melatonin biosynthetic genes was induced by melatonin. We propose that anthocyanin biosynthesis is regulated by melatonin in crabapple leaves via the expression of flavonoid related transcription factors. This study provides insight into the mechanism of melatonin induction of anthocyanin biosynthesis in woody plants, and suggests that pretreatment with melatonin may represent a cultivation strategy to increase the flavonoid contents of plants.


Assuntos
Antocianinas/metabolismo , Malus/efeitos dos fármacos , Melatonina/farmacologia , Folhas de Planta/efeitos dos fármacos , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Flavonóis/análise , Flavonóis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Malus/química , Malus/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/metabolismo
12.
J Sci Food Agric ; 99(15): 6962-6972, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31414498

RESUMO

BACKGROUND: Through precise control of the nutrient solution (NS), closed soilless systems enable targeted manipulation of plant secondary metabolites, which constitute health-promoting components of the human daily diet. A nutrient film technique (NFT) system was employed to assess the effect of NS macronutrient-based concentration (full, half-, and quarter-strength corresponding to electrical conductivity (EC) of 1.5, 0.75, and 0.5 dS m-1 ) on the bioactive profile of red and green-pigmented Salanova® butterhead lettuce. RESULTS: Half-strength NS reduced fresh biomass of both cultivars by 14%, whereas quarter-strength NS reduced the fresh biomass of green and red Salanova by 24% and 38%, respectively. However, moderate nutrient stress (half-strength NS) boosted red Salanova total ascorbic acid, chlorogenic, chicoric, caffeoyl-meso-tartaric, total phenolic acids, and anthocyanins concentrations by 266%, 199%, 124%, 251%, 162%, and 380%, respectively compared with the control, full-strength NS. CONCLUSIONS: Nutritional eustress and appropriate cultivar selection are effective means to increase phytochemical content and optimize year-round production of lettuce in closed soilless systems. © 2019 Society of Chemical Industry.


Assuntos
Alface/química , Alface/metabolismo , Nutrientes/análise , Antocianinas/análise , Antocianinas/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Hidroponia , Alface/crescimento & desenvolvimento , Nutrientes/metabolismo , Fenóis/análise , Fenóis/metabolismo , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/metabolismo , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Metabolismo Secundário
13.
Food Chem ; 300: 125147, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31349098

RESUMO

Pinot noir and Zinfandel wines were produced with traditional maceration (Control), and extended maceration for one (1 month-EM), and six months (6 months-EM). Addition of an extra amount of pomace during EM was also evaluated through a treatment referred to as Double pomace. The application of EM and Double pomace decreased the chromatic as well as the anthocyanin and anthocyanin-derived pigment composition of the wines. Large polymeric pigments were favored in EM and Double pomace wines, but the total polymeric pigment content was not improved by any of the winemaking treatments. The 6 months-EM wines showed a 13-fold (Pinot noir) and a 1.6-fold increase (Zinfandel) in tannins, respectively, relative to Control wines. However, the 1 month-EM and Double pomace treatments did not affect tannin levels, suggesting that in these wines, the extraction of tannins during EM may depend upon desorption of previously extracted tannins during extended contact time.


Assuntos
Antocianinas/análise , Manipulação de Alimentos , Taninos/análise , Vinho/análise , California , Cor , Fermentação , Vitis/química
14.
Food Chem ; 300: 125169, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336273

RESUMO

Red drupelet is a postharvest disorder of blackberries with several drupelets turning back to red. This affects visual quality and thus marketability and consumers' acceptance. However, the cause of this disorder as well as metabolite changes during color reversion have not been fully understood. Anthocyanins, cyanidin 3-glucoside, cyanidin 3-malonylglucoside, cyanidin 3-dioxalylglucoside, and total anthocyanin, were significantly lower in red drupelets than in black drupelets after 7 days of storage. Sugars and organic acids, lipids, and free amino acids also changed with storage and by color reversion. The untargeted metabolomics analyses indicated that red drupelets were generally differentiated from berries at harvest or black drupelets at metabolite level. The results of this study help better understand the red drupelet disorder. To our knowledge, this is the first study investigating red drupelet disorder by comparing black and red drupelets at metabolite level.


Assuntos
Metabolômica/métodos , Rubus/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Antocianinas/análise , Antocianinas/metabolismo , Cor , Qualidade dos Alimentos , Armazenamento de Alimentos , Frutas/química , Glucosídeos/análise , Glucosídeos/metabolismo , Lipídeos/análise , Rubus/química
15.
Food Chem ; 299: 125131, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31288159

RESUMO

The aim of this study was to research the effect of yeast fermentation on the polyphenol content of Lycium ruthenicum (LR) to guide the production of bread with a lower digestibility. Liquid fermentation from 0 to 2 h significantly increased the phenolic, flavonoid and anthocyanin content of LR, while further liquid fermentation from 2 to 16 h had little additional effect. The addition of LR without prior liquid fermentation impaired the bread quality, while a prior liquid fermentation for at least 2 h improved the bread quality. The bread digestibility was decreased after adding LR, and it was further reduced with the extended liquid fermentation time. The results of this study indicate that adding LR with prior liquid fermentation to the dough during bread making could result in a higher quality and a lower digestibility.


Assuntos
Pão , Alimentos Fortificados , Lycium/química , Antocianinas/análise , Pão/análise , Pão/microbiologia , Digestão , Fermentação , Flavonoides/análise , Qualidade dos Alimentos , Polifenóis/análise , Saccharomyces cerevisiae
16.
Food Chem ; 299: 125102, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31279126

RESUMO

The chemical compositions and α-glucosidase inhibitory activities of anthocyanins extracted from blueberry, blackcurrant and blue honeysuckle fruits and their acid hydrolysates (anthocyanidins) were analysed. Those anthocyanins were glycosidic anthocyanins that converted to anthocyanidins during acid hydrolysis, leading to increases in their α-glucosidase inhibitory activities (expressed as IC50 values) from 0.232, 0.152 and 0.188 to 0.113 to 0.005 and 0.025 mg/mL. The potential inhibitory mechanism of these anthocyanidins was then investigated through inhibition kinetics, fluorescence quenching and docking simulations. The results showed the following: 1) all anthocyanidins were mixed-type inhibitors of α-glucosidase and they bind more tightly to free α-glucosidase as compared to the α-glucosidase-substrate complex; 2) anthocyanidin inhibition of α-glucosidase was a static procedure, presumably driven by hydrophobic associations and hydrogen bonding; and 3) all anthocyanidins were inserted into the active site of α-glucosidase and avoided the entrance of p-nitrophenyl-a-D-glucopyranoside. This study is valuable for anthocyanidins as potential α-glucosidase inhibitors.


Assuntos
Antocianinas/farmacologia , Mirtilos Azuis (Planta)/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Lonicera/química , Ribes/química , Antocianinas/análise , Antocianinas/química , Fluorescência , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Simulação de Acoplamento Molecular , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
17.
Food Chem ; 299: 125092, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31280001

RESUMO

The health-promoting functions of fruit phenolic compounds are mainly attributed to their metabolites. The organic cultivation of fruits is becoming increasingly popular. Thus, this study evaluates whether the differences in red Grenache grapes derived from organic culture conditions influence the bioavailability and metabolism of phenolic compounds in rats. Organic and nonorganic (conventional) red Grenache grapes (OG and CG, respectively) were characterized and administered to Wistar rats (65 mg gallic acid equivalents/kg bw). Serum was recollected at different time points, and the phenolic metabolites were quantified by HPLC-ESI-MS/MS. The results showed that organic cultivation increased the oligomeric proanthocyanidin and anthocyanidin contents and decreased the content of free flavanols and dietary fiber. The serum profile of OG-administered rats showed higher metabolite concentrations at 2 h and reduced metabolite concentration at 24 h compared with the CG-administered rats. Thus, this particular serum kinetic behavior might influence the bioactivity of their phenolic compounds.


Assuntos
Agricultura Orgânica , Fenóis/farmacocinética , Vitis/química , Animais , Antocianinas/análise , Antocianinas/farmacocinética , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Fibras na Dieta/análise , Análise de Alimentos/métodos , Frutas/química , Masculino , Fenóis/análise , Polifenóis/análise , Polifenóis/farmacocinética , Proantocianidinas/análise , Proantocianidinas/farmacocinética , Ratos Wistar , Espectrometria de Massas em Tandem
18.
Plant Foods Hum Nutr ; 74(3): 421-429, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31280417

RESUMO

Açai (Euterpe oleracea) is a palm plant that is native to South America and produces deep purple berry fruits. Despite açai's popularity as a dietary supplement, little is known about the phenolic composition and antioxidant properties of commercially available açai berry products. Therefore, twenty açai supplements in a variety of forms (e.g., capsule, powder, frozen pulp, and liquid) were analyzed for their total phenolic and anthocyanin contents, individual anthocyanin and other flavonoid concentrations, and antioxidant capacities. Hierarchical cluster analysis was then used to group açai supplements into categories based on similarities in their chemical profiles and antioxidant properties. Results showed that over half of the supplements contained little or no açai fruit or had sufficient amounts of water to substantially lower the concentration of açai chemical components. Additionally, two açai supplements contained unlisted ingredients that greatly altered the products' chemical properties. Chromatographic analysis of individual anthocyanins and other flavonoids was useful in identifying the presence of açai fruit within the dietary supplements while complimentary in vitro spectroscopic assays aided in detection of adulterants. This study highlights the complexity of the dietary supplement market while also showing the importance of collectively analyzing data from multiple complimentary techniques when evaluating açai berry products.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Suplementos Nutricionais , Euterpe/química , Flavonoides/análise , Fenóis/análise , Frutas/química
19.
Food Chem ; 299: 125113, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31310913

RESUMO

The aim of this study was to assess content of primary and secondary metabolites of 18 plum cultivars selected in Serbia. Autochthonous cultivar 'Crvena Ranka' exhibited the highest level of total sugars (174.3 g/kg FW) while cultivar 'Mildora' had the highest sugars/acids ratio (17.2). Cultivar 'Nada' also contained high sugars/acid ratio as well as a high level of glucose and total sugars. Compared to the other cultivars, 'Nada' had a higher content of anthocyanins (27.14 mg/100 g FW), 'Crvena Ranka' neochlorogenic acid (23.21 mg/100 g FW) and flavanols (86.15 mg/100 g FW) but also the highest antioxidant activity. The PCA analysis confirmed that 'Nada' and 'Crvena Ranka' demonstrated better results in terms of sugars and antioxidant activity than the standard cultivars grown in Serbia and can be recommended for increased plum growing for fresh consumption, processing and in the breeding of plum with enhanced nutritional content.


Assuntos
Antocianinas/análise , Fenóis/análise , Prunus domestica/química , Frutas/química , Glucose/análise , Compostos Fitoquímicos/análise , Sérvia
20.
J Food Sci ; 84(8): 2199-2208, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313316

RESUMO

Bioactive anthocyanins from aqueous extracts of muscadine grape pomace were concentrated using osmotic distillation (OD) and direct contact membrane distillation (DCMD) using polypropylene (PP) and poly(ethylene chlorotrifluoroethylene) (ECTFE) membranes. The driving force for OD is created by using a high concentration brine solution while the driving force for DCMD is generated by elevating the feed temperature relative to the permeate temperature. The brine concentration used was 4 M. The lowest fluxes were obtained for OD. Given the temperature sensitive nature of anthocyanins, the maximum temperature difference during DCMD was limited to 30 °C. The feed temperature was 40 °C and the permeate at 10 °C. Consequently, the maximum flux during DCMD was also limited. A combination of OD and DCMD was found to give the highest fluxes. High-performance liquid chromatography (HPLC) and HPLC-electrospray mass spectrometry were used to identify and quantify anthocyanins, cyanidin-3,5-O-diglucoside, delphinidin-3,5-O-diglucoside, petunidin-3,5-O-diglucoside, peonidin-3,5-O-diglucoside, and malvidin-3,5-O-diglucoside. The results obtained here suggest that, though water fluxes for DI water feed streams for PP and ECTFE membrane were similar, the fluxes obtained for the two membranes when using muscadine pomace extracts were different. Concentration factors of close to 3 was obtained for anthocyanins. Membranes also showed slightly different performance in the concentration process. Membrane surfaces were analyzed using scanning electron microscopy and Fourier-transformed infrared spectroscopy. The results suggest that adsorption of these anthocyanins on the membrane surface lead to performance differences. In an actual operation, selection of an appropriate membrane and regeneration of the membrane will be important for optimized performance. PRACTICAL APPLICATIONS: Anthocyanins are valuable therapeutic compounds, which are found in the solid residue left following fruit juice pressing. However, recovery and concentration of these therapeutic compounds remains challenging due to their stability. Here, a novel membrane-based unit operation has been investigated in order to concentrate the anthocyanins that have been extracted into aqueous solutions. The unit operation investigated here use mild processing conditions. Insights into the factors that need to be considered when optimizing of the unit operation for commercialization are discussed.


Assuntos
Antocianinas/isolamento & purificação , Destilação/métodos , Manipulação de Alimentos/métodos , Extratos Vegetais/isolamento & purificação , Vitis/química , Resíduos/análise , Adsorção , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Destilação/instrumentação , Manipulação de Alimentos/instrumentação , Sucos de Frutas e Vegetais/análise , Espectrometria de Massas , Osmose , Extratos Vegetais/análise , Temperatura Ambiente
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