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1.
Food Chem ; 333: 127502, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683257

RESUMO

The aim of this study was to evaluate the effectiveness of the use of ethanol, ultrasound and/or vacuum as a pretreatment to melon drying. Eight types of pretreatments were performed in which samples were immersed in ethanol solutions with different concentrations (50% and 100%) using four treatment conditions: immersion, immersion with ultrasound (US), with vacuum (VC) and with ultrasound and vacuum (USVC). Drying was performed at 60 °C and five different semi-theoretical drying mathematical models were examined to characterize the drying curves, and quality analyses were carried out. The condition that obtained the lower drying time was using the US pretreatment in 100% ethanol solution. Drying caused a diminution of bioactive compounds and influenced color parameters. However, the samples immersed in 50% ethanol solution and dried obtained minor losses of total phenolics, total carotenoids, and ascorbic acid contents.


Assuntos
Cucurbitaceae/química , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Ácido Ascórbico/análise , Carotenoides/química , Cor , Cucurbitaceae/efeitos dos fármacos , Dessecação , Conservação de Alimentos/instrumentação , Frutas/química , Frutas/efeitos dos fármacos , Fenóis/química , Vácuo
2.
Int J Food Microbiol ; 330: 108695, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32502761

RESUMO

Norovirus (NoV) is the leading cause of epidemic and sporadic gastroenteritis worldwide; a high number of those cases are attributed to the consumption of contaminated food. Crop producers have used several strategies to inactivate the virus present in these products and thus stop the NoV transmission chain. Physical methods such as gamma radiation show excellent results in the inactivation of bacteria, but its effect on NoV has been little studied. This study aimed to evaluate the effect of gamma radiation for NoV inactivation, and over the surface topographic characteristics of strawberry cells, as a prototype of soft fruit. A 10% suspension of GII norovirus-positive stool samples were treated with either 200 mg/L of sodium hypochlorite (NaClO) or gamma-irradiated at doses of 5, 10, 15 and 20 kilograys (kGy). Viral inactivation was determined by measuring the integrity of viral capsid using RNase A alone or in combination with proteinase K followed by RT-qPCR. The effect over cellular surface topology characteristics of the fruit was measured by atomic force microscopy (AFM) and confocal microscopy. High doses of radiation (20 kGy) were necessary to detect a significant (p < 0.05) decrease of up to 1.26 log10 viral copy number. This dose significantly (p < 0.05) raises the root means square roughness (Rq), which affects directly the quality and texture of the product. The gamma irradiation doses tested in this study were not enough to inactivate NoV. The allowed gamma irradiation doses for fresh produce does not alter the surface topology of the fruit, but they affect the content of fluorescent compounds, responsible for the antioxidant activity of the fruit.


Assuntos
Fragaria/efeitos da radiação , Fragaria/virologia , Raios gama , Norovirus/efeitos da radiação , Inativação de Vírus/efeitos da radiação , Relação Dose-Resposta à Radiação , Microbiologia de Alimentos , Fragaria/efeitos dos fármacos , Frutas/efeitos dos fármacos , Frutas/efeitos da radiação , Frutas/virologia , Norovirus/fisiologia , Hipoclorito de Sódio/farmacologia , Inativação de Vírus/efeitos dos fármacos
3.
Food Chem ; 330: 127256, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540529

RESUMO

The objective of the present study was to investigate the effectiveness of different 1-MCP treatment patterns on alleviating chilling injury (CI) of postharvest nectarine stored at 0 ± 1 °C. Nectarine fruits were subjected to the following treatments: Single-High dose 1-MCP treatment (S-H): 1 µL L-1 application before storage; Multi-low dose 1-MCP treatment: (M-L) Five 0.25 µL L-1 applications after 0, 5, 10, 15, and 20 d of storage; Multi-high dose 1-MCP treatment (M-H): Five 1 µL L-1 applications after 0, 5, 10, 15 and 20 d of storage. The results showed that although all 1-MCP treatments alleviated CI, M-H 1-MCP treatment is the most effective pattern in alleviating CI of nectarine fruit in S-H, M-L, and M-H 1-MCP treatments. Moreover, this study indicated that the reduction of CI in nectarine by 1-MCP application was related to its regulations of ROS and energy metabolism.


Assuntos
Ciclopropanos/farmacologia , Prunus/efeitos dos fármacos , Temperatura Baixa , Metabolismo Energético , Armazenamento de Alimentos/métodos , Frutas/efeitos dos fármacos , Frutas/metabolismo , Néctar de Plantas , Prunus/metabolismo , Espécies Reativas de Oxigênio/metabolismo
4.
Food Chem ; 327: 127057, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464461

RESUMO

Chilling injury (CI) restricts the quality and shelf life of bell pepper fruits; reducing these CI-induced detrimental effects is therefore of high economic and agricultural relevance. Here, we investigated the effects of trisodium phosphate (TSP), salicylic acid (SA), and TSP + SA treatments on pepper fruits under cold stress at 4 °C for 25 d. Combined TSP + SA treatment performed an optimal effect. Specifically, TSP + SA treatment enhanced fatty-acid desaturation efficiency, as indicated by the increased expression of key fatty acid desaturase genes, and higher content of unsaturated fatty acids. Meanwhile, TSP + SA treatment inhibited the CI-induced membrane damage, manifested as lower electrolyte leakage and malondialdehyde content. Furthermore, low field-nuclear magnetic resonance and proline content also revealed that TSP + SA treatment mitigated CI through enhancing water retention in pepper fruits. Collectively, our results may shed new light on optimizing the low-temperature storage conditions of post-harvest peppers.


Assuntos
Capsicum/química , Ácidos Graxos/química , Fosfatos/química , Ácido Salicílico/química , Água/química , Capsicum/efeitos dos fármacos , Capsicum/metabolismo , Parede Celular/efeitos dos fármacos , Temperatura Baixa , Ácidos Graxos/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Malondialdeído/química , Malondialdeído/metabolismo , Permeabilidade/efeitos dos fármacos , Fosfatos/farmacologia , Prolina/química , Ácido Salicílico/farmacologia
5.
Food Chem ; 321: 126747, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276147

RESUMO

The strawberry fruit is perishable due to its high water content and soft texture, yet exhibits pleasant organoleptic and nutritional profile. Here we conducted a metabolomics-driven analysis followed by linear modelling to dissect the molecular processes in strawberry postharvest. Fruits from five cultivars were harvested and refrigerated during a ten-day period under three different atmospheres: ambient, CO2-enriched and O3-enriched. These analyses revealed that metabolites involved in, (i) organoleptic and nutritional properties; (ii) stress tolerance displayed duration and postharvest treatment-dependent levels. Ozone-enriched atmosphere appears to counteract postharvest negative effects, with fruits exhibiting lower levels of fermentative metabolites when compared to fruits kept in an ambient atmosphere. Furthermore, metabolic reconfiguration towards the synthesis of protective metabolites of those fruits can possibly confer enhanced tolerance to postharvest abiotic stresses. Finally, results from the linear modelling identified metabolites which could be used as biomarkers to assess strawberry quality during its postharvest shelf life.


Assuntos
Armazenamento de Alimentos/métodos , Fragaria/metabolismo , Frutas/metabolismo , Biomarcadores/metabolismo , Dióxido de Carbono/farmacologia , Fragaria/química , Fragaria/efeitos dos fármacos , Frutas/química , Frutas/efeitos dos fármacos , Modelos Lineares , Ozônio/farmacologia , Estresse Fisiológico
6.
Food Chem ; 322: 126713, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283370

RESUMO

Pre-harvest application of exogenous compounds has been employed in many crops, as a cultural practice, to promote their adaptation to a new climate-changing environment. Effect of foliar pre-harvest application of salicylic acid, glycine-betaine complex and seaweed extract (Ascophyllum nodosum) on the cherry quality from 'Staccato' cultivar was studied. Treatments significantly affected (p < 0.01) the fruit size, soluble solids content, pH, colour, polyphenols, vitamin C and antioxidant activity. Glycine-betaine and A. nodosum treated cherries presented higher dimensions, soluble solids content and pH and lower acidity. In addition, these cherries had a higher content of polyphenols and vitamin C and antioxidant capacity, but lower values of L*, C*ab and hue angle, meaning that both treatments can rise the fruit ripening process. Therefore, the pre-harvest application of glycine-betaine and A. nodosum can be a good alternative to promote the adaptation of sweet cherry tree to stressful environmental conditions, without compromising the fruit quality.


Assuntos
Ascophyllum/química , Betaína/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Glicina/farmacologia , Extratos Vegetais/farmacologia , Prunus avium/química , Alga Marinha/química , Antioxidantes/análise , Ácido Ascórbico/análise , Cor , Frutas/química , Frutas/efeitos dos fármacos , Prunus avium/efeitos dos fármacos , Controle de Qualidade
7.
Food Chem ; 321: 126701, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32283502

RESUMO

The antifungal activity of a library of twenty-four aromatic methoximes was examined against five representative postharvest phytopathogenic fungi. The panel included Penicillium digitatum, Penicillium italicum, Rhizopus stolonifer, Botrytis cinerea and Monilinia fructicola, all of which cause relevant economic losses worldwide as a result of affecting harvested fruits. The minimum inhibitory concentrations and minimum fungicidal concentrations of each compound were defined and the main structure-activity relationships were determined. Although other congeners were more potent, drug likeliness considerations pointed to the methoxime derived from 2,4-dihydroxypropiophenone as the compound with the most suitable profile. The morphology of the colonies of the fungal strains treated with the methoxime was examined microscopically and the compound was also tested in freshly harvested peaches and oranges, exhibiting promising control profiles in both fruits, similar to those of the commercial agents Imazalil and Carbendazim.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Frutas/microbiologia , Oximas/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Citrus sinensis/efeitos dos fármacos , Citrus sinensis/microbiologia , Frutas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oximas/farmacologia , Penicillium/efeitos dos fármacos , Prunus persica/efeitos dos fármacos , Prunus persica/microbiologia , Rhizopus/efeitos dos fármacos , Relação Estrutura-Atividade
8.
Artigo em Inglês | MEDLINE | ID: mdl-32259674

RESUMO

Phenolic compounds, such as phytoalexin resveratrol, can be induced in grapes in response to biotic and abiotic stresses and have been related in many healthy effects. Stilbene synthases (STSs) are the key enzyme responsible for resveratrol biosynthesis. They have been already isolated and characterized from several plant species, however, VviSTS is a multigene family and little is known about their modulation in response to the application of gaseous treatments that maintain table grapes quality during postharvest. In this work, we have analyzed the effect of a 3-day CO2 treatment on the modulation of 4 STSs (VviSTS6, VviSTS7, VviSTS16 and VviSTS46) and on the accumulation of different stilbene compounds (resveratrol, resveratrol-glucoside, trans-piceatannol, z-miyabenol and pallidol) during the postharvest storage at 0 °C of white (Superior Seedless, Dominga), red (Red Globe) and black (Autumn Royal) table grapes. Results indicated that the accumulation of the stilbene compounds by the application of CO2 and low temperature storage were cultivar dependent. In white Dominga fruit, accumulation of stilbene compounds increased in CO2-treated samples what seems to be modulated by VviSTS6, VviSTS7 and VviSTS46. However, in Red Globe the accumulation of compounds was mainly due to the cold storage in air and seems to be also mediated by the induction of the same VviSTSs. By contrast, in Superior Seedless and Autumn Royal table grapes the modulation of VviSTSs genes and the stilbene accumulation was independent of the atmosphere storage. Further studies would be needed to elucidate the possible role of transcription factors involved on VviSTSs modulation.


Assuntos
Dióxido de Carbono , Temperatura Baixa , Regulação da Expressão Gênica , Estilbenos , Vitis , Dióxido de Carbono/farmacologia , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Frutas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Estilbenos/metabolismo , Vitis/efeitos dos fármacos , Vitis/genética
9.
Food Chem ; 320: 126635, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32213422

RESUMO

In pear, sucrose was mainly distributed in vacuole; and the alternation of sucrose abundance was associated the change of vacuolar invertase (VI) activity during fruit storage. However, the molecular mechanism beneath such phenomenon has not been clarified until recently. For this, a combination of metabolite, enzyme activity, transcriptome, quantitative real-time PCR (qRT-PCR), bioinformation, subcellular localization, and transient overexpression assay was conducted in this study to identify the acid invertase 1 (PbrAc-Inv1) and invertase inhibitor 5 (PbrII5) involved in sucrose degradation during 'Housui' pear storage. Both PbrAc-Inv1 and PbrII5 were located in vacuolar membrane. PbrAc-Inv1 could accelerate sucrose degradation; on the other hand, PbrII5 could bind with PbrAc-Inv1 to form a inactive complex, downregulate the VI activity, and suppressed sucrose decomposition. Based on Bio-layer interferometry (BLI) result after domain substitution, the domain on the left of catalytic 'WEC-P/V-D' box in PbrAc-Inv1 might played a key role in its interaction with PbrII5.


Assuntos
Inibidores Enzimáticos/farmacologia , Pyrus/efeitos dos fármacos , Pyrus/enzimologia , Sacarose/metabolismo , beta-Frutofuranosidase/antagonistas & inibidores , beta-Frutofuranosidase/metabolismo , Frutas/efeitos dos fármacos , Frutas/metabolismo , Hidrólise , Pyrus/genética , Pyrus/metabolismo , Vacúolos/enzimologia , beta-Frutofuranosidase/genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-32114399

RESUMO

Having a central role in cell wall pectin cross-linking, calcium has been increasingly used as supplement to promote fruit firmness and extended shelf-life. However, the molecular rearrangements associated to increased fruit robustness are still a matter of debate. In this study, mechanical, histochemical and molecular assays were conducted to understand the mechanisms underlying the effects of Ca in fruit physical properties. In a two-year field trial, grapevines were sprayed with exogenous CaCl2 throughout the fruiting season. Results showed an increase in berry Ca concentration at harvest, associated to increased fruit consistency and skin resistance. Scanning electron microscopy showed that fruits from Ca-treated plants had smoother skin surfaces than control fruits, and that microcracks encircling the lenticels were less prominent. Histochemistry assays suggested higher deposition of pectin-like material in skin cell walls in grapes from Ca-treated vines, but no evident modifications in cellulose content were observed. Accordingly, the expression of cellulose synthase family gene CesA3 was not affected by exogenous Ca, while polygalacturonase-encoding genes PG1 and PG2 were downregulated, together with EXP6 belonging to expansin family, and CER9 and CYP15 involved in cuticle biosynthesis. These results suggested that Ca acts by inhibiting pectin degradation and cell wall loosening, while remodeling cuticle structure.


Assuntos
Cloreto de Cálcio , Frutas , Vitis , Cálcio/metabolismo , Cloreto de Cálcio/farmacologia , Parede Celular/efeitos dos fármacos , Frutas/efeitos dos fármacos , Frutas/ultraestrutura , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Poligalacturonase/genética , Vitis/efeitos dos fármacos
11.
Plant Mol Biol ; 103(1-2): 91-111, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32043226

RESUMO

KEY MESSAGE: Auxin treatment of grape (Vitis vinifera L.) berries delays ripening by inducing changes in gene expression and cell wall metabolism and could combat some deleterious climate change effects. Auxins are inhibitors of grape berry ripening and their application may be useful to delay harvest to counter effects of climate change. However, little is known about how this delay occurs. The expression of 1892 genes was significantly changed compared to the control during a 48 h time-course where the auxin 1-naphthaleneacetic acid (NAA) was applied to pre-veraison grape berries. Principal component analysis showed that the control and auxin-treated samples were most different at 3 h post-treatment when approximately three times more genes were induced than repressed by NAA. There was considerable cross-talk between hormone pathways, particularly between those of auxin and ethylene. Decreased expression of genes encoding putative cell wall catabolic enzymes (including those involved with pectin) and increased expression of putative cellulose synthases indicated that auxins may preserve cell wall structure. This was confirmed by immunochemical labelling of berry sections using antibodies that detect homogalacturonan (LM19) and methyl-esterified homogalacturonan (LM20) and by labelling with the CMB3a cellulose-binding module. Comparison of the auxin-induced changes in gene expression with the pattern of these genes during berry ripening showed that the effect on transcription is a mix of changes that may specifically alter the progress of berry development in a targeted manner and others that could be considered as non-specific changes. Several lines of evidence suggest that cell wall changes and associated berry softening are the first steps in ripening and that delaying cell expansion can delay ripening providing a possible mechanism for the observed auxin effects.


Assuntos
Parede Celular/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Células Vegetais/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Vitis/efeitos dos fármacos , Crescimento Celular/efeitos dos fármacos , Parede Celular/genética , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Naftalenoacéticos/farmacologia , Células Vegetais/fisiologia , Tempo , Vitis/crescimento & desenvolvimento
12.
Food Chem ; 316: 126335, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32062231

RESUMO

Glycine betaine (GB) is known to alleviate chilling injury in many fruit species. Therefore, we studied how GB affects the biosynthesis of esters in 'Nanguo' pears. Based on the kinds of esters, total esters, and the quantity of the main esters, it was evident that aroma losses were alleviated by GB treatment. In addition, unsaturated fatty acids contents (linoleic and linolenic acid) and the activities of lipoxygenase (LOX) and alcohol acyltransferase (AAT) enzymes were also increased. Meanwhile, comparing with the control fruit, the genes directly involved in ester synthesis were up-regulated in the GB-treated fruit. In addition, an increase in the activities and gene expression of antioxidant enzymes was observed in the treated samples. Thus, GB treatment promotes the synthesis of esters by regulating the LOX pathway and increasing antioxidant capacity, thereby effectively improving the quality of esters in cold-stored fruit.


Assuntos
Betaína/farmacologia , Ésteres/metabolismo , Lipoxigenase/metabolismo , Odorantes/análise , Pyrus/efeitos dos fármacos , Pyrus/metabolismo , Antioxidantes/metabolismo , Temperatura Baixa , Frutas/efeitos dos fármacos , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Metabolismo dos Lipídeos , Proteínas , Pyrus/genética
13.
J Agric Food Chem ; 68(10): 3267-3276, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32101430

RESUMO

Cross-talk between various hormones is important in regulating many aspects of plant growth, development, and senescence, including fruit ripening. Here, exogenous ethylene (ETH, 100 µL/L, 12 h) rapidly accelerated 'Hayward' kiwifruit (Actinidia deliciosa) softening and ethylene production and was enhanced by supplementing with continuous treatment with methyl jasmonate (MeJA, 100 µM/L, 12 h) (ETH+MeJA). ETH+MeJA enhanced ACC synthase (ACS) activities and 1-aminocyclopropane-1-carboxylic acid (ACC) accumulation but not ACC oxidase (ACO) activity. Increased transcripts of ACS genes AdACS1 and AdACS2, ACS activity, and ethylene production were positively correlated. The abundance of AdACS1 was about 6-fold higher than AdACS2. RNA-seq identified 6 transcription factors among the 87 differentially expressed unigenes induced by ETH+MeJA. Dual-luciferase and electrophoretic mobility shift assays (EMSA) indicated that AdNAC2/3 physically interacted with and trans-activated the AdACS1 promoter 2.2- and 3.5-fold, respectively. Collectively, our results indicate that MeJA accelerates ethylene production in kiwifruit induced by exogenous ethylene, via a preferential activation of AdACS1 and AdACS2.


Assuntos
Acetatos/farmacologia , Actinidia/efeitos dos fármacos , Coenzima A Ligases/metabolismo , Ciclopentanos/farmacologia , Etilenos/biossíntese , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oxilipinas/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Actinidia/enzimologia , Actinidia/genética , Actinidia/metabolismo , Frutas/efeitos dos fármacos , Frutas/enzimologia , Frutas/genética , Frutas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/genética
14.
Food Chem ; 317: 126407, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32078996

RESUMO

In this study, we compared the chemical composition of strawberry (Fragaria × ananassa) fruits that were ripened in vivo (attached to plant) to those ripened during postharvest storage. The effects of the application of abscisic acid (ABA) and sucrose on the postharvest ripening were also evaluated. The results suggested that the postharvest ripening process was dependent on the signal triggered by ABA and differed from in vivo ripening, resulting in fruits with altered chemical composition and firmness. The application of sucrose in unripe strawberries resulted in the induction of ripening, which is dependent on ABA and its derivatives. This induction was more pronounced during the first days of storage and associated with the application of mannitol rather than water, suggesting that mannitol negatively regulated the postharvest strawberry ripening. These results provide further insights into the role of ABA and sucrose in the regulation of postharvest ripening of strawberry.


Assuntos
Ácido Abscísico/farmacologia , Fragaria/fisiologia , Frutas/efeitos dos fármacos , Sacarose/farmacologia , Ácido Abscísico/metabolismo , Antocianinas/metabolismo , Armazenamento de Alimentos , Fragaria/efeitos dos fármacos , Frutas/metabolismo , Frutas/fisiologia , Manitol/farmacologia , Fenóis/análise
15.
Food Chem ; 315: 126295, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32014671

RESUMO

Effect of nano-SiO2 packing on postharvest quality and antioxidant capacity of two different loquat cultivars (white-flesh 'Qingzhong' and red-flesh 'Dawuxing') were determined. Results showed that nano-SiO2 packing significantly inhibited internal browning, retarded the decline of total soluble solids, titratable acidity, ascorbic acid content and extractable juice in both cultivars. Decay index of nano-SiO2 packing in 'Dawuxing' and 'Qingzhong' was 53.25% and 42.84% lower than control after the day 12, respectively. Meanwhile, nano-SiO2 packing enhanced the contents of individual phenolic compounds and soluble sugar compounds, induced higher superoxide dismutase and catalase activities, which contributed to improving 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radical scavenging capacity. Furthermore, the contents of total soluble solids, ascorbic acid and soluble sugar were higher in 'Qingzhong' than those in 'Dawuxing', which dedicated to better quality. These results indicated that nano-SiO2 packing was a promising approach in inhibiting decay, maintaining quality and expanding shelf life of loquats.


Assuntos
Antioxidantes/farmacologia , Eriobotrya/efeitos dos fármacos , Dióxido de Silício/farmacologia , Ácido Ascórbico/análise , Eriobotrya/química , Armazenamento de Alimentos , Frutas/química , Frutas/efeitos dos fármacos , Nanoestruturas , Fenóis/análise , Superóxido Dismutase/metabolismo , Temperatura
16.
Planta ; 251(3): 65, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060652

RESUMO

MAIN CONCLUSION: Swelling of sweet cherry cell walls is a physical process counterbalanced by turgor. Cell turgor prevents swelling in intact cells, whereas loss of turgor allows cell walls to swell. Swelling of epidermal cell walls precedes skin failure in sweet cherry (Prunus avium) cracking. Swollen cell walls lead to diminished cell:cell adhesions. We identify the mechanism of cell wall swelling. Swelling was quantified microscopically on epidermal sections following freeze/thaw treatment or by determining swelling pressure or swelling capacity of cell wall extracts. Releasing turgor by a freeze/thaw treatment increased cell wall thickness 1.6-fold within 2 h. Pressurizing cell wall extracts at > 12 kPa prevented swelling in water, while releasing the pressure increased swelling. The effect was fully reversible. Across cultivars, cell wall thickness before and after turgor release in two subsequent seasons was significantly correlated (before release of turgor: r = 0.71**, n = 14; after release of turgor: r = 0.73**, n = 14) as was the swelling of cell walls upon turgor release (r = 0.71**, n = 14). Close relationships were also identified for cell wall thickness of fruit of the same cultivars grown in the greenhouse and the field (before release of turgor: r = 0.60, n = 10; after release of turgor: r = 0.78**, n = 10). Release of turgor by heating, plasmolysis, incubation in solvents or surfactants resulted in similar swelling (range 2.0-3.1 µm). Cell wall swelling increased from 1.4 to 3.0 µm as pH increased from pH 2.0 to 5.0 but remained nearly constant between pH 5.0 and 8.0. Increasing ethanol concentration decreased swelling. Swelling of sweet cherry cell walls is a physical process counterbalanced by turgor.


Assuntos
Parede Celular/metabolismo , Frutas/citologia , Prunus avium/citologia , Parede Celular/efeitos dos fármacos , Frutas/efeitos dos fármacos , Sucos de Frutas e Vegetais , Concentração de Íons de Hidrogênio , Osmose , Epiderme Vegetal/citologia , Epiderme Vegetal/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Pressão , Prunus avium/efeitos dos fármacos , Sacarose/farmacologia , Fatores de Tempo
17.
J Agric Food Chem ; 68(7): 1986-1997, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31986044

RESUMO

In this study, the impact of cerium oxide nanoparticles on the nutritional value of tomato (Solanum lycopersicum) fruit grown in soil infested with Fusarium oxysporum f. sp. lycopersici was investigated in a greenhouse pot study. Three-week old seedlings of Bonny Best tomato plants were exposed by foliar and soil routes to nanoparticle CeO2 (NP CeO2) and cerium acetate (CeAc) at 0, 50, and 250 mg/L and transplanted into pots containing a soil mixture infested with the Fusarium wilt pathogen. Fruit biomass, water content, diameter, and nutritional content (lycopene, reducing and total sugar) along with elemental composition, including Ce, were evaluated. Fruit Ce concentration was below the detection limit in all treatments. Foliar exposure to NP CeO2 at 250 increased the fruit dry weight (67%) and lycopene content (9%) in infested plants, compared with the infested untreated control. Foliar exposure to CeAc at 50 mg/L reduced fruit fresh weight (46%) and water content (46%) and increased the fruit lycopene content by 11% via root exposure as compared with the untreated infested control. At 250 mg/L, CeAc increased fruit dry weight (94%), compared with the infested untreated control. Total sugar content decreased in fruits of infested plants exposed via roots to NP CeO2 at 50 mg/kg (63%) and 250 mg/kg (54%), CeAc at 50 mg/kg (46%), and foliarly at 50 mg/L (50%) and 250 mg/L (50%), all compared with the infested untreated control. Plants grown in Fusarium-infested soil had decreased fruit dry weight (42%) and lycopene content (17%) and increased total sugar (60%) and Ca content (140%), when compared with the noninfested untreated control (p ≤ 0.05). Overall, the data suggested minimal negative effects of NP CeO2 on the nutritional value of tomato fruit while simultaneously suppressing Fusarium wilt disease.


Assuntos
Cério/farmacologia , Frutas/química , Fungicidas Industriais/farmacologia , Fusarium/fisiologia , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Fusarium/efeitos dos fármacos , Lycopersicon esculentum/química , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Nanopartículas/química , Valor Nutritivo , Solo/química , Microbiologia do Solo
18.
Food Chem ; 314: 126182, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31968293

RESUMO

Flavonoids are key determinants of grape quality and wine color. Grapevines growing in alkaline soil are prone to manganese deficiency, which can decrease the contents of secondary metabolites, including flavonoids. We determined the effects of a foliar Mn treatment (MnSO4·H2O) of Cabernet Sauvignon grapevines (V. vinifera L.) growing in alkaline soil on the flavonoid contents in grape skin, and the quality of wine. The Mn treatments were applied in 2017 and 2018, and tended to increase the grape sugars, berry weight, and the contents of phenolic compounds from veraison until harvest. The Mn treatments increased the amounts of acetylated, methylated, and total anthocyanins, as well as the total flavonol contents in grape berry skin at harvest. The wines prepared from these grapes had a higher color intensity than those prepared from grapes from control vines. Foliar-applied MnSO4·H2O can promote flavonoid biosynthesis in grape berries, and improve the color of wine.


Assuntos
Agricultura/métodos , Flavonoides/metabolismo , Compostos de Manganês/farmacologia , Sulfatos/farmacologia , Vitis/efeitos dos fármacos , Vinho/análise , Antocianinas/análise , Antocianinas/metabolismo , China , Cor , Flavonoides/análise , Flavonóis/análise , Flavonóis/metabolismo , Frutas/efeitos dos fármacos , Frutas/metabolismo , Fenóis/análise , Fenóis/metabolismo , Folhas de Planta , Solo/química , Vitis/metabolismo
19.
Food Chem ; 313: 126123, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31923871

RESUMO

Calcium supplements have increasingly been used at pre- and post-harvest stages for improving fruit firmness, but elevated calcium levels in grape cells were shown to reduce total anthocyanin content. In this study, we hypothesized that exogenous calcium influences specific polyphenolic compounds, and performed targeted UPLC-MS analysis in fruits collected from vines cv. "Vinhão" sprayed with 2% (w/v) CaCl2 throughout the fruiting season, in two consecutive vintages, and in grape cell cultures elicited with calcium. Results showed that anthocyanin content is reduced upon calcium treatment, while stilbenoid synthesis is generally stimulated, in line with UFGT and STS expression patterns. The main metabolites involved in this response were malvidin-3-O-glucoside, E-piceid, E-ε-viniferin and E-resveratrol. The accumulation of phenolic acids, catechin and some quercetin derivatives was also favored by calcium, while other flavonols and flavan-3-ols were affected according to the vintage and berry developmental stage. In cell cultures, the entire flavonoid pathway was repressed.


Assuntos
Antocianinas/análise , Cálcio/farmacologia , Estilbenos/análise , Vitis/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Análise dos Mínimos Quadrados , Espectrometria de Massas em Tandem , Vitis/química , Vitis/metabolismo
20.
Food Chem ; 310: 125818, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31787397

RESUMO

Research on plant biostimulants is of interest in their potential benefits for agriculture production and environmental sustainability. These naturally occurring products induce beneficial consequences in plant metabolism and productivity. In most cases their modes of action, and consequences for the whole plant as well as parts, such as the fruit, are well characterized, but the precise mechanisms of action require further attention. This study examined the effects of the commercial biostimulant, Actium®, on Capsicum annuum L. cv Palermo leaves and fruits. The influence of time (characterized by ripening), after 14 and 28 days of treatment, treatment regimen, and their combined impact on the metabolome were studied using HPLC-ESI-QTOF-MS analysis of polar and apolar compounds. The results showed that flavonoids and capsianosides decreased with ripening in leaves, but organic acids, monosaccharides, and carotenoids increased in fruits. The treatment of Capsicum fruits with Actium® increased phenylalanine and total monosaccharides (glucose and fructose) compared to controls, suggesting a further stage in ripening. An increase in carotenoids concomitant with an increase of some digalactosyl diacylglycerols, which are part of the chromoplasts lipid machinery of enzymes involved in the synthesis of carotenoids, was also observed. Our findings suggest that this biostimulant may increase some metabolites related to pepper fruit maturity and coloration in pepper crops.


Assuntos
Capsicum/metabolismo , Frutas/metabolismo , Metaboloma , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/metabolismo , Capsicum/efeitos dos fármacos , Carotenoides/metabolismo , Cromatografia Líquida de Alta Pressão , Produtos Agrícolas/metabolismo , Frutas/efeitos dos fármacos , Frutas/fisiologia , Metabolômica , Monossacarídeos/metabolismo , Fenilalanina/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Espectrometria de Massas por Ionização por Electrospray
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