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1.
Foods ; 13(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338536

RESUMO

Algal biostimulants are increasingly integral to vegetable cultivation due to their capacity to boost yield, alleviate abiotic and biotic stress, and enhance overall crop quality. This study evaluated the impact of two commercially available algal-based biostimulants on cucumber (Cucumis sativus L.), examining their effects on yield, number of fruits, dry weight, color, flesh thickness, skin thickness, plastid pigments, and tocopherol content. Both biostimulant treatments resulted in a roughly 13% decrease in yield and fruit number compared to the control treatment. Notably, the biostimulants positively influenced the fruit brightness parameter (L*), leading to darker fruits. Fitostim® algal biostimulant exhibited a positive effect on dry weight during the initial harvest. The predominant pigments were chlorophyll a and chlorophyll b (constituting 80% of all analyzed pigments), and the most abundant tocopherol was α-tocopherol, comprising 80% to 90% of tocopherols. Skin tissues contained significantly higher levels of pigments and tocopherols compared to flesh. Both biostimulants caused a notable decrease in total tocopherol content in the skin at the first harvest, with reductions of 19.91 mg/kg DW for Phylgreen® and 9.43 mg/kg DW for Fitostim® algae. The study underscores the variable efficacy of biostimulants, emphasizing their dependence on the specific biostimulant type and fruit part. The application of biostimulants has the potential to substantially enhance the internal quality of cucumbers, particularly in terms of plastid pigments and tocopherols, offering potential health benefits for consumers.

2.
Foods ; 12(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36673463

RESUMO

The consumption of fresh vegetables has been consistently associated with numerous health benefits. However, several factors (such as allelochemicals) influence yield, quality, and metabolites, which inevitably affect the fruit quality and health benefits. The present study was conducted to investigate the yield, quality, metabolic responses, and potential toxicity of Cucumis sativus grown in juglone-containing soils. For the treatments, pure juglone (100 µM, 1 mM) and walnut leaf extracts (100 µM) in soil concentrations found in walnut orchards were used. A total of 36 phenolic compounds were identified and quantified in fruits, leaves, and roots using a mass spectrometer coupled with high-performance liquid chromatography. We concluded that juglone at a concentration of 100 µM or walnut leaf extract at the same juglone concentration does not affect the yield of C. sativus, while juglone at a concentration of 1 mM strongly affects it. In the case of juglone, juglone itself was found only in the roots of C. sativus, but not in the leaves or fruits, so C. sativus fruits are considered safe for cultivation in juglone-containing soils. However, this could prove problematic if the plants grown are tubers or root vegetables. The data suggest that juglone itself inhibits secondary metabolism in the plant, making it more susceptible to stress and pathogen attacks.

3.
Plants (Basel) ; 11(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36432780

RESUMO

Different climatic conditions are known to affect the synthesis of primary and secondary metabolites. Therefore, the phenolic contents in new growing areas could affect the quality and flavor of hazelnuts. The aim of this study was to determine the variability of the phenolic contents of the kernels in different commercial hazelnut cultivars depending on their growing area. Five cultivars ('Tonda Gentile delle Langhe', 'Merveille de Bollwiller', 'Pauetet', 'Tonda di Giffoni', and 'Barcelona' (syn. 'Fertile de Coutard')) grown in different European collection orchards were included in the study. High-performance liquid chromatography coupled with mass spectrometry was used to identify and quantify the phenolic compounds. Thirteen phenols were identified in the hazelnut kernels, including 7 flavanols, 2 hydroxybenzoic acids, 3 flavonols, and one dihydrochalcone. Catechin and procyanidin dimers were the main phenolic compounds found in the hazelnut kernels. The highest contents of catechin and total flavanols were determined in cultivars cultivated in Spain and northern Italy, and the lowest in Slovenia and France. Flavanols were the major phenolic groups independent of the place of cultivation, as they accounted for more than 50% of all phenolic compounds identified. The flavanols were followed by hydroxybenzoic acids, flavonols, and dihydrochalcones. Higher contents of flavanols and flavonols were found in kernels from areas characterized by higher natural irradiation, which stimulates their accumulation. The contents of hydroxybenzoic acids correlated with altitude, which stimulated phenolic acid synthesis. A negative correlation was observed between the dihydrochalcone content and annual rainfall, probably due to hydric stress.

4.
Foods ; 11(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35954023

RESUMO

Chili olive oil is a popular addition to various foods in many countries. In a detailed study, the content of phenols and capsaicinoids in chili olive oil was determined using chili flakes and whole chilies. A total of 99.8% of the phenols in chili olive oil were secoiridoids, with elenolic acid, oleuropein aglycones, and ligostride aglycones being the most abundant. Chili olive oil with chili flakes contained higher levels of capsaicinoids (+21.6%) compared to whole chili olive oil. Capsaicin and dihydrocapsaicin accounted for about 95% of all capsaicinoids in the chili olive oil. The extraction rate of dry "Cayenne" chili was 7.1% in whole chili olive oil and 9% in chili olive oil with flakes, confirming that chili flakes are better extracted in olive oil. With the determination of 29 individual phenols and five individual capsaicinoids, the study provided a detailed insight into the secondary metabolites of chili olive oil and confirmed that it is a health source.

5.
Biology (Basel) ; 11(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35625402

RESUMO

Biostimulants are widely used in agriculture because they can improve fruit quality and quantity. Less is known about how biostimulants act over time in plants, in our case peppers, and how they affect the enzyme activity of important enzymes for capsaicinoid synthesis. The biostimulatory effects of amino acids on the activities of phenylalanine ammonia lyase (PAL), capsaicin synthase (CS), and peroxidase (POX) were investigated in the pericarp and placenta of the chili pepper Capsicum baccatum L. cv. "Bishop Crown" over 72 h of application. The PAL and CS activities significantly increased in the placenta after 1 h of biostimulant application, with significant increases of 130% and 16%, respectively. The POX activity remained unchanged over the full 72 h in the placenta but significantly increased after 48 h in the pericarp (+53%). Total capsaicinoids increased in the first hour of biostimulant application, by 4.30 g/kg FW in the placenta (19%) and by 0.94 g/kg FW in the pericarp (+56%). Biostimulant application also increased total and individual capsaicinoids after 48 h in the chili placenta and pericarp. With improved methods for enzymatic determination, we gained new insights into the responses of chilies to biostimulant amino acids.

6.
Plants (Basel) ; 11(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35406833

RESUMO

A total of four Capsicum annuum L. genotypes ('Caro F1', 'Berenyi F1', 'Somborka' and 'Novosadka') were exposed to two intensities of salt stress. We observed a significant decrease in the sugar content in all salt stressed treatments, except for the sucrose content of the pericarp of the 'Caro F1' cultivar. Salt stress had a largely negative effect on the total and individual organic acid content, although the effect differed among cultivars. Using high performance liquid chromatography coupled with a mass spectrometer, most phenolics were identified in the pericarp (18), followed by the placenta (7) and seeds (8). Treatment with 40 mM NaCl caused the highest increase in individual phenols, followed by treatment with 20 mM NaCl. The cultivar 'Berenyi F1' was less affected by salt stress treatment than the other three cultivars in terms of content of individual and total phenols. Salt stress increased the content of capsaicinoids in all the cultivars. The pericarp of the cultivar 'Novosadka' showed 17.5 and 50 times higher total capsaicinoid content than the control in the 20 mM and 40 mM NaCl, respectively. With the results of several metabolite groups, we confirmed that the reaction and metabolic content to salt stress within the genus Capsicum is genotype-, fruit part-, and salinity level-dependent.

7.
Front Nutr ; 8: 731869, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692746

RESUMO

Lamb's lettuce is a popular winter salad, often grown in private vegetable plots, small local farms or in intensive vegetable production. It is usually marketed as a ready-to-eat produce in supermarkets. The aim of the study was to evaluate the changes in biochemical composition and degradation of bioactive compounds during consumer-relevant time of home-grown and store-bought Valerianella locusta "Vit" salad. Primary metabolites, assimilatory pigments as well as secondary metabolites were monitored during 1 week of refrigerated storage. Home-grown lamb's lettuce exhibited highest levels of total sugars, total organic acids, vitamin C, and total phenolic content as well as enhanced levels of most individual phenolic compounds and chloroplast pigments. Locally produced samples of lamb's lettuce also contained high levels of analyzed bioactive components. All samples retained most bioactive components during the entire period of refrigerated storage. The results underline the instability of vitamin C during refrigerated storage of lamb's lettuce and pinpoint this parameter as being the most affected by storage.

8.
Sci Rep ; 11(1): 4932, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654228

RESUMO

Twenty-one different cultivars from four different species were examined. The highest dry weight was present in seeds (between 35 and 50%) and the average water content was 60%. Placenta and pericarp contained on average 86% water. Total sugars variation between species was 60%. The most concentrated in the various cultivar pericarps were ascorbic acid ranging from 368.1 to 2105.6 mg/100 g DW and citric acid ranging from 1464.3 to 9479.9 mg/100 g DW. Total phenolic content ranged from 2599.1 mg/100 DW in 'Chilli AS- Rot' to 7766.7 mg/100 g DW in 'Carolina Reaper'. The placenta had 23.5 times higher phenolic content than seeds. C. chinense and C. chinense × C. frutescens had 3.5 to 5 times higher capsaicinoid content compared to C. annuum and C. baccatum, with 'Carolina Reaper' having the highest content at 7334.3 mg/100 g DW and 'Chilli AS- Rot' the lowest (318.7 mg/100 g DW).


Assuntos
Capsicum/metabolismo , Fenóis/metabolismo , Sementes/metabolismo , Especificidade da Espécie
9.
Plants (Basel) ; 11(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35009104

RESUMO

Chilies are widely cultivated for their rich metabolic content, especially capsaicinoids. In our study, we determined individual sugars, organic acids, capsaicinoids, and total phenolic content in pericarp, placenta, and seeds of Capsicum annuum L., Capsicum chinense Jacq. and Capsicum baccatum L. by HPLC/MS. Dry weight varied in the cultivar 'Cayenne', with the first fruit having the lowest dry weight, with 4.14 g. The total sugar content and organic acid content did not vary among the fruits of all three cultivars. The cultivar 'Cayenne' showed differences in total phenolic and capsaicinoid content between fruits in the placenta, with the first fruit having the highest content of total phenolics (27.85 g GAE/kg DW) and total capsaicinoids (16.15 g/kg DW). Of the three cultivars studied, the cultivar 'Habanero Orange' showed the least variability among fruits in terms of metabolites. The content of dihydrocapsaicin, nordihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin in the seeds of the second fruit was higher than that of the first fruit of the cultivar 'Bishop Crown'. The results of our study provided significant insight into the metabolomics of individual fruits of the same chili plant. We have thus increased our understanding of how certain metabolites are distributed between fruits at different levels of the same plant and different parts of the fruit. This could be further investigated when chilies are exposed to different environmental stresses.

10.
J Sci Food Agric ; 101(2): 778-785, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32706119

RESUMO

BACKGROUND: Japanese dogwood (Cornus kousa Burg.) is a popular ornamental plant which develops edible compound fruit utilized in traditional Asian medicine. Previous compositional studies have focused on a small fraction of secondary metabolites at a single maturity stage. In order to address the question of optimal ripeness of Japanese dogwood fruit for consumption the study provides a comprehensive insight into its primary and secondary metabolic profile. RESULTS: The aim of the study was to investigate biochemical composition and morphological traits of Japanese dogwood (Cornus kousa Burg.) fruit at four maturity stages: GF, green fruit; BF, fruit with a defined red blush; RF, ripe fruit; OF, over-ripe fruit. Fruit was characterized by a nearly spherical shape, decreased water content in later stages of ripeness and highest a* values at RF and OF stages. Total sugars increased significantly from GF to OF stage and total organic acids and vitamin C decreased with maturation. Japanese dogwood fruit was characterized by four major phenolic groups: anthocyanins (three), flavonols (eight) hydroxycinnamic acids (three) and flavonoids (one) as well as by four lipophilic antioxidants: tocopherols (two), xanthophylls (five), carotenes (two) and chlorophylls (two). The progression of fruit ripening caused faster accumulation of individual phenolic compounds and lipophilic antioxidants which resulted in significantly higher total phenolic content at the RF and OF stages. CONCLUSION: Japanese dogwood fruit is a rich alternative source of ascorbic acid, α-tocopherol, flavonols and anthocyanins and should be consumed fresh at fully developed red colour of compound berries when their composition is optimal. © 2020 Society of Chemical Industry.


Assuntos
Cornus/crescimento & desenvolvimento , Frutas/química , Antocianinas/análise , Antocianinas/metabolismo , Antioxidantes/análise , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Cornus/química , Cornus/metabolismo , Ácidos Cumáricos/análise , Ácidos Cumáricos/metabolismo , Flavonoides/análise , Flavonoides/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Fenóis/análise , Fenóis/metabolismo
11.
BMC Plant Biol ; 18(1): 216, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30285622

RESUMO

BACKGROUND: Commercially available poinsettia (Euphorbia pulcherrima) varieties prevalently accumulate cyanidin derivatives and show intense red coloration. Orange-red bract color is less common. We investigated four cultivars displaying four different red hues with respect to selected enzymes and genes of the anthocyanin pathway, putatively determining the color hue. RESULTS: Red hues correlated with anthocyanin composition and concentration and showed common dark red coloration in cultivars 'Christmas Beauty' and 'Christmas Feeling' where cyanidin derivatives were prevalent. In contrast, orange-red bract color is based on the prevalent presence of pelargonidin derivatives that comprised 85% of the total anthocyanin content in cv. 'Premium Red' and 96% in cv. 'Harvest Orange' (synonym: 'Orange Spice'). cDNA clones of flavonoid 3'-hydroxylase (F3'H) and dihydroflavonol 4-reductase (DFR) were isolated from the four varieties, and functional activity and substrate specificity of the corresponding recombinant enzymes were studied. Kinetic studies demonstrated that poinsettia DFRs prefer dihydromyricetin and dihydroquercetin over dihydrokaempferol, and thus, favor the formation of cyanidin over pelargonidin. Whereas the F3'H cDNA clones of cultivars 'Christmas Beauty', 'Christmas Feeling', and 'Premium Red' encoded functionally active enzymes, the F3'H cDNA clone of cv. 'Harvest Orange' contained an insertion of 28 bases, which is partly a duplication of 20 bases found close to the insertion site. This causes a frameshift mutation with a premature stop codon after nucleotide 132 and, therefore, a non-functional enzyme. Heterozygosity of the F3'H was demonstrated in this cultivar, but only the mutated allele was expressed in the bracts. No correlation between F3'H-expression and the color hue could be observed in the four species. CONCLUSIONS: Rare orange-red poinsettia hues caused by pelargonidin based anthocyanins can be achieved by different mechanisms. F3'H is a critical step in the establishment of orange red poinsettia color. Although poinsettia DFR shows a low substrate specificity for dihydrokaempferol, sufficient precursor for pelargonidin formation is available in planta, in the absence of F3'H activity.


Assuntos
Códon sem Sentido , Sistema Enzimático do Citocromo P-450/genética , Euphorbia/genética , Proteínas de Plantas/genética , Oxirredutases do Álcool/genética , Antocianinas/genética , Antocianinas/metabolismo , Clonagem Molecular , Euphorbia/metabolismo , Regulação da Expressão Gênica de Plantas , Pigmentação/genética , Reação em Cadeia da Polimerase em Tempo Real
12.
J Agric Food Chem ; 66(11): 2742-2748, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29494766

RESUMO

A rare walnut variant with a red seed coat (pellicle) was examined for alterations in its phenolic profile during development. The red-walnut (RW) pellicle was compared with two commonly colored walnut varieties: 'Lara' (brown) and 'Fernor' (light brown). Furthermore, the activities of selected enzymes of the phenylpropanoid- and flavonoid-related pathways and the relative expressions of the structural genes phenylalanine ammonia lyase ( PAL) and anthocyanidin synthase ( ANS) were examined in the pellicles of the three varieties. In the pellicles of the RWs, phenylalanine ammonia lyase (PAL) activity and related PAL expression was most pronounced in August, about one month before commercial maturity, suggesting a high synthesis rate of phenolic compounds at this development stage. The most pronounced differences between the red and light- and dark-brown varieties were the increased PAL activity, PAL expression, and ANS expression in RWs in August. The vibrant color of the RW pellicle is based on the presence of four derivatives of cyanidin- and delphinidin-hexosides.


Assuntos
Antocianinas/biossíntese , Juglans/química , Nozes/crescimento & desenvolvimento , Oxigenases/genética , Fenóis/química , Fenilalanina Amônia-Liase/genética , Proteínas de Plantas/genética , Antocianinas/química , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Juglans/enzimologia , Juglans/genética , Juglans/crescimento & desenvolvimento , Nozes/química , Nozes/genética , Nozes/metabolismo , Oxigenases/metabolismo , Fenóis/metabolismo , Fenilalanina/metabolismo , Fenilalanina Amônia-Liase/metabolismo , Proteínas de Plantas/metabolismo
13.
Food Chem ; 252: 349-355, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29478553

RESUMO

In studies of secondary metabolites in nuts, many constituents in the kernel remain unidentified due to a high content of phenolic compounds in the pellicle. In the present study, we focused on the investigation of the phenolic and dicarboxylic acid profiles of walnut and hazelnut pellicle-less kernels. High-performance liquid chromatography with diode array and mass spectrometric detection (HPLC-DAD-MSn) was used to carry out the determination of individual phenolics and dicarboxylic acids in brown and red-pellicle walnut and hazelnut. Results show that hexahydroxydiphenic acid (HHDP) di-galloyl hexose isomer, vanillic acid hexoside, quinic acid derivative and catechin are the main constituents of the phenolic profile of walnut, while galloylquinic derivative, caffeoyl hexoside and catechin are the main constituents of the hazelnut kernel. Even though both walnut and hazelnut kernels have a considerably lower content of phenolic compounds and dicarboxylic acids in comparison to the pellicles, when calculated as a percentage of the total mass, the kernel makes a significant contribution to the total phenolic content of the whole nut.


Assuntos
Juglans/química , Nozes/crescimento & desenvolvimento , Fenóis/química , Extratos Vegetais/química , Catequina/química , Cromatografia Líquida de Alta Pressão , Cor , Corylus/química , Corylus/crescimento & desenvolvimento , Juglans/crescimento & desenvolvimento , Espectrometria de Massas , Nozes/química
14.
PLoS One ; 12(12): e0190246, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29272302

RESUMO

Relative expressions of structural genes and a number of transcription factors of the anthocyanin pathway relevant in Vaccinium species, and related key enzyme activities were compared with the composition and content of metabolites in skins of ripe fruits of wild albino and blue bilberry (Vaccinium myrtillus) found in Slovenia. Compared to the common blue type, the albino variant had a 151-fold lower total anthocyanin and a 7-fold lower total phenolic content in their berry skin, which correlated with lower gene expression of flavonoid 3-O-glycosyltransferase (FGT; 33-fold), flavanone 3-hydroxylase (FHT; 18-fold), anthocyanidin synthase (ANS; 11-fold), chalcone synthase (CHS, 7.6-fold) and MYBPA1 transcription factor (22-fold). The expression of chalcone isomerase (CHI), dihydroflavonol 4-reductase (DFR), leucoanthocyanidin reductase (LAR), anthocyanidin reductase (ANR) and MYBC2 transcription factor was reduced only by a factor of 1.5-2 in the albino berry skins, while MYBR3 and flavonoid 3',5'-hydroxylase (F3'5'H) were increased to a similar extent. Expression of the SQUAMOSA class transcription factor TDR4, in contrast, was independent of the color type and does therefore not seem to be correlated with anthocyanin formation in this variant. At the level of enzymes, significantly lower FHT and DFR activities, but not of phenylalanine ammonia-lyase (PAL) and CHS/CHI, were observed in the fruit skins of albino bilberries. A strong increase in relative hydroxycinnamic acid derivative concentrations indicates the presence of an additional bottleneck in the general phenylpropanoid pathway at a so far unknown step between PAL and CHS.


Assuntos
Antocianinas/metabolismo , Genes de Plantas , Genes Reguladores , Vaccinium myrtillus/metabolismo , Regulação da Expressão Gênica de Plantas , Fenóis/metabolismo , Eslovênia , Especificidade da Espécie , Vaccinium myrtillus/genética
15.
J Agric Food Chem ; 64(40): 7459-7465, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27626626

RESUMO

A common technological practice in Brussels sprouts (Brassica oleracea L. var. gemmifera) production is the removal of apical plant section a few weeks before harvest in order to promote the development of auxiliary buds (sprouts) and ensure higher yields. It is well-known that this measure positively influences the size of the sprouts, but until now no study has focused on the effect of decapitation on the content of primary and secondary metabolites in Brussels sprouts. Plants were decapitated one month before harvest, and sprouts were sampled from three sections along the stem (basal, middle, top) of each plant. The sprouts were harvested, weighed, and chemically analyzed. The content of individual sugars was assessed by HPLC and the content of individual phenolics and glucosinolates by HPLC-MS. Significant interactions between the decapitation and different stem sections were detected in the weight of the sprouts, as well as in their sugar levels. The highest sugar content was determined in basal sprouts collected from decapitated plants. Conversely, basal sprouts from nondecapitated plants were characterized by the lowest sugar content. No interaction between the decapitation and stem sections was detected in the level of phenolics or glucosinolates. Decapitation promoted the accumulation of all glucosinolates and hydroxycinnamic acids. Moreover, the content of glucosinolates and flavonoids was always highest in the sprouts from the top stem section.


Assuntos
Agricultura/métodos , Brassica/química , Brassica/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Qualidade dos Alimentos , Glucosinolatos/análise , Monossacarídeos/análise , Fenóis/análise , Caules de Planta/crescimento & desenvolvimento
16.
J Food Sci ; 80(9): C1952-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26243178

RESUMO

The distribution of betalains in peel, flesh, and petioles of yellow and red beetroot cultivars has been investigated using an High-performance liquid chromatography (HPLC) system with electrospray mass spectrometry. Differences in the levels of betacyanins and betaxanthins between different colored cultivars were individually determined for 3 plant parts. The content of almost all analyzed compounds decreased in the following order: peel > flesh > petiole. Betanin/isobetanin pigments comprised a major portion of the relative peak area measured in red beetroot peel. Isobetanin relative peak areas were also high in leaf petioles (68.94% to 74.16%) of red colored cultivars. However, betacyanins were completely absent from the extracts of all analyzed parts of yellow beet. Glutamine-bx represented a very high relative peak area (59.54% to 64.18%) in flesh of red-colored cultivars analyzed in the study. Our results indicate that red beet cultivars can be utilized as a potential source of red and yellow natural colorants. However, differences in pigment composition among different beetroot parts must be considered and in order to maximize the pigment yields petioles can also be used as a source rich in specific betalain compounds.


Assuntos
Beta vulgaris/química , Betacianinas/análise , Betaxantinas/análise , Pigmentos Biológicos/análise , Estruturas Vegetais/química , Beta vulgaris/classificação , Betalaínas/análise , Cromatografia Líquida de Alta Pressão/métodos , Corantes de Alimentos , Humanos , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Especificidade da Espécie , Verduras/química
17.
Food Chem ; 185: 41-7, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25952839

RESUMO

The purpose of this study was to investigate composition and content of phenolic compounds in seeds of common buckwheat (Fagopyrum esculentum Moench) cultivars from Western, Central and Southeastern Europe grown in the Balkan area, and to compare them with cultivars from the Balkan. Mostly detected hydroxycinnamic acids in seeds of the investigated cultivars were caffeic and chlorogenic acid derivatives. More than ten different flavanols were detected in the investigated seeds, based on which all tested buckwheat cultivars were divided into two groups: those with high propelargonidins (epiafzelechin-epicatechin) and those with high procyanidins contents. 'Novosadska' had the highest level of phenolic acids, proanthocyanidins, flavones and most of the flavonols. However, 'Bosna 1' and 'Bosna 2' were highlighted with the greatest rutin content (up to 46 times higher than in other cultivars). All buckwheat cultivars had quite high antioxidant capacity (more than 80% of neutralized radicals), yet, 'Novosadska', 'Godijevo', 'Spacinska 1' and 'Bamby' excelled.


Assuntos
Antioxidantes/análise , Fagopyrum/química , Fagopyrum/classificação , Fenóis/análise , Biflavonoides/análise , Catequina/análise , Cromatografia Líquida de Alta Pressão , Europa (Continente) , Espectrometria de Massas , Extratos Vegetais/química , Proantocianidinas/análise , Rutina/análise , Sementes/química
18.
J Sci Food Agric ; 95(4): 776-85, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25186189

RESUMO

BACKGROUND: As a part of the ongoing interest in nutritional and nutraceutical properties of locally produced fruits, the aim of the article was to determine sugars, organic acids, polyphenols and antioxidant capacity of wild bilberries grown in Slovenia. Primary and secondary metabolite composition of bilberry fruit was compared among six phyto-climatic conditions, differing in photosynthetic active radiation and light intensity. RESULTS: Three sugars were quantified in bilberry fruit, the predominant being fructose and glucose, along with five organic acids. Bilberry fruit contained high levels of anthocyanins (cyanidin, delphinidin, malvidin, petunidin and peonidin glycosides), hydroxycinnamic acid derivatives and low levels of flavonol glycosides (mainly quercetin and myricetin glycosides), flavan-3-ols, proanthocyanidins and iridoids. The results of the study indicate that bilberries growing in sites with high photosynthetic active radiation (PAR) contained higher levels of total sugars, anthocyanins, flavonols and hydroxycinnamic acids and lower levels of organic acids compared with bilberry fruit from low-light locations. Consequently, total phenolic content and antioxidative capacity of the fruit from high-PAR locations were significantly increased. CONCLUSION: Bilberries from different natural habitats differ significantly in the quantity of sugars, organic acids and phenolic compounds. Our results contribute to a fuller understanding of the relationships between environmental factors and accumulation of primary and secondary metabolites in bilberry fruits.


Assuntos
Antioxidantes/análise , Qualidade dos Alimentos , Frutose/análise , Frutas/crescimento & desenvolvimento , Glucose/análise , Polifenóis/análise , Vaccinium myrtillus/crescimento & desenvolvimento , Antioxidantes/metabolismo , Análise por Conglomerados , Florestas , Frutose/biossíntese , Frutas/química , Frutas/metabolismo , Frutas/efeitos da radiação , Glucose/biossíntese , Polifenóis/biossíntese , Eslovênia , Luz Solar , Vaccinium myrtillus/química , Vaccinium myrtillus/metabolismo , Vaccinium myrtillus/efeitos da radiação , Tempo (Meteorologia) , Meio Selvagem
19.
Food Chem ; 173: 363-74, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466034

RESUMO

There are no defined maturity parameters for berry fruit which often results in harvesting and marketing of inedible, immature or over ripe berries. In the present study the changes in quality characteristics of different white-, red-, and black-currant cultivars as well as gooseberry and jostaberry fruit were investigated at three maturity stages. Colour parameters, berry juice pH level and the content of sugars, organic acids and phenolic compounds have been evaluated. A total of 65 different phenolic compounds were detected by HPLC-PDA/MS. The results indicate that, during the last 2-4 weeks of fruit ripening, significant changes occur in colour parameters, primary and secondary metabolites and radical scavenging activity. The results suggest that the average content of specific phenolic groups and sugars/acids ratio can be used as a simple and reliable maturity index for optimisation of harvest time.


Assuntos
Extratos Vegetais/análise , Ribes/química , Carboidratos/análise , Frutas/química , Frutas/classificação , Frutas/crescimento & desenvolvimento , Fenóis/análise , Ribes/classificação , Ribes/crescimento & desenvolvimento
20.
Food Chem ; 173: 935-42, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466109

RESUMO

Antioxidant activity and polyphenols were quantified in vapour-extracted juice of nine Austrian, partially endemic varieties of sweet cherry (Prunus avium): cv. 'Spätbraune von Purbach', cv. 'Early Rivers', cv. 'Joiser Einsiedekirsche', cv. 'Große Schwarze Knorpelkirsche' and four unidentified local varieties. Additionally the effect of storage was evaluated for six of the varieties. A variety showing the highest antioxidant capacity (9.64 µmol Trolox equivalents per mL), total polyphenols (2747 mg/L) and total cyanidins (1085 mg/L) was suitable for mechanical harvest and its juice did not show any losses of antioxidant capacity and total anthocyanin concentration during storage. The juice of cv. 'Große Schwarze Knorpelkirsche' had also high concentrations of total anthocyanins (873 mg/L), but showed substantial losses through storage. The local Austrian sweet cherry varieties from the Pannonian climate zone are particularly suitable for the production of processed products like cherry juice with high content of anthocyanins and polyphenols.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Polifenóis/análise , Prunus/química , Extratos Vegetais/química
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