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1.
Food Chem ; 303: 125346, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446364

RESUMO

The effect of a respiratory quotient dynamic controlled atmosphere (DCA - RQ), which induces ethanol production through low oxygen storage, and ethanol application on softening of Braeburn apples stored at different temperatures was investigated. DCA - RQ storage was associated with the activation of the alcohol dehydrogenase (ADH) and greater anaerobic metabolism in comparison with DCA - CF (chlorophyll fluorescence) and controlled atmosphere (CA) storage. Greater anaerobic metabolism resulted in lower ethylene production, ACC oxidase activity, membrane permeability, -galactosidase activity and, therefore, less softening after long-term storage. Ethanol application after CA storage decreased ethylene biosynthesis, respiration rate and membrane permeability. Storage at 3 °C resulted in the lowest soluble solids and acidity, but not softening. In conclusion, Braeburn apples could be stored at 3 °C under DCA - RQ1.5. Additionally, ethanol produced by the fruit, or applied externally, had a significant effect on inhibiting softening during and after storage.


Assuntos
Atmosfera , Etanol/farmacologia , Malus/efeitos dos fármacos , Malus/metabolismo , Oxigênio/metabolismo , Anaerobiose/efeitos dos fármacos , Frutas/efeitos dos fármacos , Frutas/metabolismo
2.
Food Chem ; 303: 125400, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470275

RESUMO

Siraitia grosvenorii fruit (SGF) has been used as a natural sweetener and traditional medicine in China for more than two centuries. This study evaluated the effect of SGF extract supplementation (0.5%, 1%, and 2%) on the chemical, microbial and sensory properties of probiotic yogurt. The antioxidant, angiotensin-converting-enzyme inhibitory (ACE-I) and antibacterial bioactivities were determined. SGF extract supplementation improved some of the chemical and physicochemical characteristics. Probiotic yogurt with the fruit extract had significantly more Lactobacillus casei and Lactobacillus bulgaricus, whereas there was no significant effect on the number of Streptococcus thermophiles. The bioactivities were significantly increased by SGF extract supplementation. Probiotic yogurt with 2% SGF extract showed the highest antioxidant, ACE-I, and antibacterial activities, whereas the one with 1% SGF extract conferred the highest sensory attributes score. Overall, SGF extract offers a promising option as a dietary supplement to produce novel dairy products that have high nutritional and bioactivity values.


Assuntos
Cucurbitaceae/química , Aditivos Alimentares/análise , Extratos Vegetais/análise , Probióticos/análise , Iogurte/microbiologia , Inibidores da Enzima Conversora de Angiotensina/análise , Antioxidantes/análise , China , Frutas/efeitos dos fármacos , Humanos , Lactobacillus casei/genética , Lactobacillus casei/crescimento & desenvolvimento , Lactobacillus casei/isolamento & purificação , Lactobacillus delbrueckii/genética , Lactobacillus delbrueckii/crescimento & desenvolvimento , Lactobacillus delbrueckii/isolamento & purificação , Peptidil Dipeptidase A/química , Paladar , Iogurte/análise
3.
Food Chem ; 302: 125337, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419770

RESUMO

The composition of volatile compounds in Korla fragrant pears was determined using headspace solid-phase microextraction followed by a gas chromatography-mass spectrometry analysis using fruits at 30, 90, and 150 days after bloom. Hexanal, (E)-2-hexenal, 1-hexanol, (E)-2-hexen-1-ol, (Z)-3-hexen-1-ol, and hexyl acetate were identified as the major compounds. The composition of volatile compounds was associated with fatty acid concentrations and key enzyme activity in the lipoxygenase pathway. In vitro linoleic and linolenic acid feeding experiments conducted using cubes of fruit flesh demonstrated that the concentrations of volatile esters, such as hexyl acetate, in the treated fruits increased significantly after incubation for 12 h compared with those in the control fruits, which was accompanied by a reduction in aldehyde and alcohol concentrations (p < 0.05 or p < 0.01). However, the treatments did not significantly influence the enzyme activity and expression of genes encoding the enzymes.


Assuntos
Frutas/química , Odorantes/análise , Pyrus/química , Pyrus/fisiologia , Compostos Orgânicos Voláteis/análise , Aldeídos/análise , Ésteres/análise , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Análise de Alimentos/métodos , Frutas/efeitos dos fármacos , Frutas/fisiologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Regulação da Expressão Gênica de Plantas , Hexanóis/análise , Ácido Linoleico/farmacologia , Pyrus/efeitos dos fármacos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/metabolismo , Ácido alfa-Linoleico/farmacologia
4.
Food Chem ; 303: 125385, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442899

RESUMO

In this study, the mechanism activated by melatonin treatment at 100 µM for maintaining nutraceutical properties in pomegranate fruits during storage at 4 °C for 120 days was investigated. Our results showed that the higher G6PDH and 6PGDH activities in pomegranate fruits treated with melatonin may be responsible for sufficient supply of intracellular NADPH. Also, higher AA and GSH accumulation in pomegranate fruits treated with melatonin may ascribe to higher APX and GR activities coincided with lower AAO activity. In addition, pomegranate fruits treated with melatonin exhibited significantly higher PAL activity resulting in higher phenols and anthocyanins accumulation as well as higher DPPH scavenging capacity. Additionally, higher AOX gene expression in pomegranate fruits treated with melatonin may be beneficial for ROS scavenging molecules accumulation. Therefore, maintaining nutraceutical properties of pomegranate fruits treated with melatonin may ascribe to sufficient intracellular NADPH supply by promoting G6PDH and 6PGDH activities during cold storage.


Assuntos
Antocianinas/análise , Conservação de Alimentos , Melatonina/farmacologia , Punicaceae/efeitos dos fármacos , Suplementos Nutricionais/análise , Frutas/química , Frutas/efeitos dos fármacos , Punicaceae/química
5.
Biol Res ; 52(1): 43, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31405373

RESUMO

BACKGROUND: Drought is one of the main serious problems for agriculture production which its intensity is increasing in many parts of the world, hence, improving water use efficiency is a main goal for sustainable agriculture. RESULTS: Growth indices including relative shoot length growth (SL), relative stem diameter increase (SD) and relative trunk cross sectional area growth (TCSA) measured at the start and end of the season decreased by reducing the irrigation level. Chlorophyll index (CI) was decreased at 70% crop evapotranspiration, however water use efficiency (WUE), leaf and fruit total phenolic content (TPC), and fruit anthocyanin content (AC) were among the traits that showed increment by water deficit stress in both cultivars. Shafi-Abadi cultivar showed to be more sensitive to the water stress than 'Golab'. Kaolin treatment improved SL, SD and CI traits, but this increase was statistically significant only for SD at 5% level. Kaolin had no significant effect on yield and water use efficiency (WUE), however, it had negative effect on yield efficiency (YE). Kaolin treatments also significantly increased fruit and leaf TPC (P < 0.01) but had no effect on leaf and fruit total antioxidant activity (AA), as well as fruit anthocyanin content (AC) and soluble proteins (SP). CONCLUSIONS: Irrigation at 85% ETc showed better results than 100% and 70% ETc levels for yield attributes. It seems that the more pronounced effect of kaolin on vegetative traits but not on the fruits, might be attributed to the early ripening and harvest time of the examined cultivars.


Assuntos
Irrigação Agrícola/métodos , Secas , Frutas/crescimento & desenvolvimento , Caulim/administração & dosagem , Malus/crescimento & desenvolvimento , Frutas/efeitos dos fármacos , Malus/efeitos dos fármacos , Estações do Ano
6.
J Sci Food Agric ; 99(15): 6859-6867, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31385314

RESUMO

BACKGROUND: In this study, we analyzed the effect of the application of high levels of CO2 (20 kPa CO2 + 20 kPa O2 + 60 kPa N2 ) for 3 days at low temperature on a white table-grape cultivar (Superior Seedless) in comparison with a black one (cv. Autumn Royal) in terms of quality parameters. We also used a solid-state voltammetry methodology to analyze the effect of the 3-day gaseous treatment in berry tissues from both cultivars in the first stage of storage. We determined the role of the non-enzymatic (total phenols, total anthocyanins, and antioxidant activity) and the enzymatic antioxidant (catalase (GCAT), ascorbate peroxidase (VcAPX) gene expression) systems in the behaviors of both cultivars. RESULTS: Our results indicate that the application of a 3-day gaseous treatment was effective in maintaining the quality of black and white table grapes for up to 28 days of storage at 0 °C. The electrochemical methodology applied was useful for differentiating between skin and pulp samples, and between black and white table grape cultivars. Some molecular mechanisms were modulated in the skin of both cultivars to overcome oxidative stress, which was not manifested with the same intensity in grapes treated with CO2 for 3 days. However, some differences were observed in relation to the non-enzymatic system. CONCLUSION: The 3-day gaseous treatment was useful to maintain black and white table grape quality at 0 °C. The voltammetry analysis indicated that CO2 -treated samples from the skin and pulp showed more similarity to freshly harvested ones. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/análise , Dióxido de Carbono/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Vitis/efeitos dos fármacos , Antioxidantes/metabolismo , Ascorbato Peroxidases/genética , Ascorbato Peroxidases/metabolismo , Dióxido de Carbono/química , Catalase/genética , Catalase/metabolismo , Cor , Conservantes de Alimentos/química , Armazenamento de Alimentos , Frutas/química , Frutas/efeitos dos fármacos , Gases/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Vitis/química , Vitis/enzimologia , Vitis/genética
7.
Food Chem ; 301: 125303, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31387045

RESUMO

The effects of exogenous polyamines treatment on reactive oxygen species (ROS) metabolism in apricot fruits were systematically analyzed through the investigation of their curative and preventive effects on black spot disease. Results showed that 1.5 mM spermine (Spm), 1.5 mM spermidine (Spd) and 10 mM putrescine (Put) treatment significantly inhibited black spot development, additionally, the efficacy of this control was dependent upon the type of polyamines used and concentration level applied. Further studies have shown that exogenous polyamines treatments significantly improved production of O2- and H2O2, and increased the activities and gene expression levels of NADPH oxidase (NOX), super oxide dismutase (SOD), catalase (CAT) ascorbate peroxidase (AXP) and glutathione reductase (GR) in apricot fruit. Increased ascorbic acid (AsA) and reduced glutathione (GSH) content were also observed after exogenous polyamines treatment. These results have revealed that postharvest polyamines treatment effectively enhanced disease resistance through the maintenance of homeostasis in apricot fruits.


Assuntos
Alternaria/patogenicidade , Frutas/efeitos dos fármacos , Doenças das Plantas/microbiologia , Poliaminas/farmacologia , Prunus armeniaca/efeitos dos fármacos , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Resistência à Doença/efeitos dos fármacos , Frutas/metabolismo , Frutas/microbiologia , Glutationa/metabolismo , Glutationa Redutase/metabolismo , Homeostase/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Oxirredução , Prunus armeniaca/metabolismo , Prunus armeniaca/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
8.
Food Chem ; 301: 125311, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398670

RESUMO

We assessed the effects of postharvest exogenous melatonin (50,100 and 150 µmol L-1) on the senescence and quality of sweet cherries during storage at 0 ±â€¯0.5 °C. Melatonin treatment decreased decay incidence, respiration rate, and weight loss. It delayed the degradation of firmness, lightness, saturation, hue angle, titratable acidity, and total soluble solids content, thus maintaining better fruit quality. Melatonin treatment inhibited increases in O2-, H2O2, malondialdehyde content, and relative membrane permeability, while maintaining higher endogenous melatonin levels and increasing superoxide dismutase and catalase activity. Additionally, melatonin treatment enhanced the activity of antioxidant enzymes, increased the levels of ascorbic acid, and reduced glutathione levels, which are related to the ascorbate-glutathione cycle, as well as increasing the AsA:DHA and GSH:GSSG ratios. Delayed senescence in sweet cherries after exogenous melatonin treatment may be associated with high endogenous melatonin levels and increased antioxidant activity and content.


Assuntos
Armazenamento de Alimentos/métodos , Frutas/efeitos dos fármacos , Melatonina/farmacologia , Prunus avium/efeitos dos fármacos , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Qualidade dos Alimentos , Frutas/fisiologia , Glutationa/metabolismo , Malondialdeído/metabolismo , Melatonina/metabolismo , Oxirredução , Prunus avium/fisiologia , Superóxido Dismutase/metabolismo
9.
J Agric Food Chem ; 67(35): 9958-9966, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31419123

RESUMO

Chilling injury (CI) is a physiological disorder induced by cold, which heavily limit crop production and postharvest preservation worldwide. Methyl jasmonate (MeJA) can alleviate CI in various fruit species, including peach; however, the underlying molecular mechanism is poorly understood. Here, changes in contents of phenolics, lipids, and jasmonic acid (JA) and gene expressions are compared between MeJA and control fruit. Exogenous MeJA inhibited expressions of PpPAL1, PpPPO1, and PpPOD1/2 but did not affect the phenolic content. Furthermore, MeJA fruit showed lower relative electrolyte leakage, indicating less membrane damage. Meanwhile, the enrichment of linoleic acid in the potential lipid biomarkers, especially phosphatidylcholine, phosphatidylethanolamine, and phosphatidylglycerol, coincided with lower expressions of PpFAD8.1 but higher PpLOX3.1 and JA content. In the JA signaling pathway, MeJA significantly upregulated expressions of PpMYC2.2 and PpCBF3 but downregulated PpMYC2.1. In conclusion, adjustments of fatty acids in phospholipids contribute to MeJA-induced alleviation of CI in peach fruit via induction of the JA-mediated C-repeat-binding factor pathway.


Assuntos
Acetatos/farmacologia , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Frutas/efeitos dos fármacos , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Fosfolipídeos/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Prunus persica/metabolismo , Temperatura Baixa , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prunus persica/efeitos dos fármacos , Prunus persica/genética , Prunus persica/crescimento & desenvolvimento
10.
Food Chem ; 298: 125069, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260991

RESUMO

The effects of ethanol treatment on quality characteristics of cherry tomatoes were investigated over 11 days of storage at room temperature (25 °C). Results showed that sensory quality was improved after ethanol treatment, with redder, softer fruits at the edible stage (11 days) compared with control fruit. In addition, the contents of ascorbic acid, sucrose and fructose were elevated after ethanol treatment as well as the concentration of 6-methyl-5-hepten-2-one. Conversely, decreased levels of methyl salicylate (MeSA), guaiacol, (Z)-3-hexenal and (E)-2-hexenal were observed. Selected consumers showed a preference for ethanol-treated cherry tomato fruits compared with controls. Taken together, 0.1% ethanol application has the potential to improve the quality characteristics of cherry tomatoes stored at room temperature.


Assuntos
Etanol/farmacologia , Lycopersicon esculentum/efeitos dos fármacos , Aldeídos/química , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Aromatizantes/análise , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Humanos , Análise dos Mínimos Quadrados , Lycopersicon esculentum/química , Lycopersicon esculentum/metabolismo , Salicilatos/química , Açúcares/análise , Temperatura Ambiente , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação
11.
J Sci Food Agric ; 99(14): 6350-6363, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31273796

RESUMO

BACKGROUND: Recent studies report that Ascophyllum nodosum extracts, once applied on the canopy of different crops, deliver positive effects, increasing yield, inducing tolerance to biotic stress, and improving the quality of products. However, the mechanisms of action are still unclear. In this research, vines subjected to multiple foliar applications of an A. nodosum extract (ANE) at label doses were compared with untreated vines (NTV) in accordance with a comparative approach. The investigation coupled a field experiment with a second trial conducted under semi-controlled conditions, to clarify the mechanisms of action involved. RESULTS: The biostimulant did not affect soluble solids or the acidity of grapes; instead, it improved their anthocyanin and phenolic concentrations and the respective profiles. At the time of harvest, anthocyanin, and phenolic concentration were increased by 10.4% and 14.5%, respectively, when compared to the NTV. These effects correlated with a specific modulation of genes involved in the flavonoid metabolic pathways. Moreover, grapes from ANE vines witnessed a significant reduction in the spreading of gray mold when they were either assessed in field conditions or in vitro, compared to the grapes of NTV vines. This was related to a significant upregulation of the defense-related genes of the plant. CONCLUSIONS: Overall, the results showed that A. nodosum extracts can be valuable tools in viticulture considering the emergence of challenging environmental conditions; hence, the regulation of specific metabolic pathways is the mechanism of action that leads to an increased tolerance of biotic stress and of changes in the content of grape metabolites. © 2019 Society of Chemical Industry.


Assuntos
Ascophyllum/química , Extratos Vegetais/farmacologia , Vitis/efeitos dos fármacos , Vitis/metabolismo , Antocianinas/análise , Antocianinas/metabolismo , Flavonoides/análise , Flavonoides/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Fenóis/análise , Fenóis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Vitis/química , Vitis/crescimento & desenvolvimento
12.
J Sci Food Agric ; 99(14): 6408-6417, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31283020

RESUMO

BACKGROUND: Blood orange is sensitive to chilling injury (CI) depending on cultivar and storage temperature. Postharvest treatments with γ-aminobutyric acid (GABA), methyl jasmonate (MeJA), or methyl salicylate (MeSA) are known to alleviate CI. γ-Aminobutyric acid aqueous solution, applied at 20 and 40 mM, was vacuum-infiltrated at 30 kPa for 8 min at 20 °C. Methyl jasmonate or MeSA vapor treatments were applied separately at 50 and 100 µM by putting the fruit in 20 L plastic containers for 18 h at 20 °C. There have been no reports about postharvest treatments of GABA, MeJA, or MeSA on enhancing the tolerance of 'Moro' blood orange to chilling during long-term cold storage at 3 °C for 150 days, which was the subject of this study. RESULTS: All treatments significantly alleviated CI symptoms of blood orange manifested by lower electrolyte leakage (EL), malondialdehyde (MDA), hydrogen peroxide (H2 O2 ) concentrations, and higher proline content in flavedo during storage. The largest effects were obtained with 100, 50 µM, and 40 mM for MeSA, MeJA, and GABA, respectively, which enhanced the activity of the antioxidant enzymes catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL). On the other hand, these treatments suppressed peroxidase (POD) and polyphenol oxidase (PPO) activities. CONCLUSION: The mechanisms involved in enhancing the tolerance of 'Moro' blood orange to chilling could involve scavenging H2 O2 by increasing the activity of antioxidant enzymes, higher PAL/PPO activity ratio, and osmoregulation by increasing proline content. These changes led to the maintenance of the epidermis structure. This was confirmed by scanning electron microscopy (SEM) micrographs. © 2019 Society of Chemical Industry.


Assuntos
Acetatos/farmacologia , Citrus sinensis/efeitos dos fármacos , Ciclopentanos/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/efeitos dos fármacos , Oxilipinas/farmacologia , Salicilatos/farmacologia , Ácido gama-Aminobutírico/farmacologia , Ascorbato Peroxidases/metabolismo , Catalase , Citrus sinensis/química , Temperatura Baixa , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Frutas/química , Proteínas de Plantas/metabolismo
13.
J Sci Food Agric ; 99(14): 6562-6571, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31321778

RESUMO

BACKGROUND: Excessive reactive oxygen species (ROS) may attack biological macromolecules and induce oxidative stress. The inhibition by ascorbic acid (AsA) on oxidative damage has been reported in fruits, while the barrier effect of ceramide has also been proven. However, there are few reports about the effects of ceramide-AsA interactions to enhance storability and boost antioxidant systems in fruits during storage. This study was conducted to study the synergistic effects of AsA in combination with ceramide on the quality of postharvest strawberry (Fragaria anannasa cv. Tianbao). RESULTS: Treatment with 100 mg L-1 AsA plus 1.2 mmol L-1 ceramide significantly delayed the rot of strawberries, reduced the water loss and the contents of ROS, malonaldehyde (MDA), and proline, however, increased the contents of total flavonoids, total phenols, and anthocyanins compared with other treatments. Also, treatment with 100 mg L-1 AsA plus 1.2 mmol L-1 ceramide significantly increased the activities of peroxidase (POD) and superoxide dismutase (SOD) but inhibited the activity of polyphenol oxidase (PPO). CONCLUSION: It is suggested that treatment with 100 mg L-1 AsA plus 1.2 mmol L-1 ceramide could significantly reduce the oxidative damage and maintain the storage quality of strawberries during storage by enhancing the antioxidant systems. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Ceramidas/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Fragaria/efeitos dos fármacos , Catalase/metabolismo , Sinergismo Farmacológico , Armazenamento de Alimentos , Fragaria/química , Fragaria/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
14.
Food Chem ; 300: 125223, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31362157

RESUMO

The impact of fungicides mepanipyrim (Mep) and tetraconazole (Tetra) and their corresponding commercial formulations (Mep-Form and Tetra-Form) on the aroma composition of wines was assessed. Fungicide residues can affect the biotransformation of aroma precursors from grapes and/or the yeast metabolism. The results confirmed that both maximum residue levels (MRL and 2xMRL) of Mep promoted benzyl alcohol and 4-vinylguaiacol contents; while MRL and 2xMRL of Mep-Form promoted benzene derivatives (benzyl alcohol, benzaldehyde, and trans-isoeugenol), 2-phenylethanol and γ-nonalactone. The addition of Tetra (2xMRL) and Tetra-Form (MRL and 2xMRL) release higher contents of cis-3-hexen-1-ol and ethyl vanillate and affected yeast metabolism related to phenylacetaldehyde, 2-phenylethanol, methionol, capric acid, ethyl 2-methylbutyrate, ethyl isovalerate, ethyl monosuccionate, diethyl succinate and γ-butyrolactone production. Fungicide residues did not display higher variations in global odour activity values with respect to control wines, although some variations on the "floral", "fruity", "spicy" and "lactic" nuances could be sensed.


Assuntos
Clorobenzenos/farmacologia , Pirimidinas/farmacologia , Triazóis/farmacologia , Vitis/efeitos dos fármacos , Compostos Orgânicos Voláteis/metabolismo , Vinho , Fermentação , Contaminação de Alimentos/análise , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Fungicidas Industriais , Odorantes/análise , Vitis/química , Vitis/metabolismo , Compostos Orgânicos Voláteis/análise , Vinho/análise , Vinho/microbiologia , Leveduras/efeitos dos fármacos , Leveduras/metabolismo
15.
J Sci Food Agric ; 99(14): 6296-6306, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31260121

RESUMO

BACKGROUND: Blueberries are appreciated by consumers for their rich natural antioxidants and their good nutritional and health functions. However, blueberries are very perishable due to microbial infection and metabolic aging after harvest. Ethanol has been shown to have the effect of controlling postharvest microorganisms and improving storage quality of fruits and vegetables. This study aimed to clarify the effects of ethanol on the appearance quality and flavor attributes of postharvest blueberries. Blueberries were treated with ethanol (250, 500, and 1000 µL L-1 ) and stored at 0 ± 0.5 °C, 90% relative humidity (RH), for 40 days. RESULTS: The results indicated that ethanol treatment could slow the decline of blueberry firmness and reduce the decay rate significantly in a dose-dependent manner. The soluble solids content (SSC) and titratable acidity (TA) of ethanol-treated blueberries increased significantly (P < 0.05), improving the taste of the blueberries. The activities of alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC) were stimulated with the accumulation of ethanol in blueberries, which catalyzed the conversion of ethanol, acetaldehyde, and pyruvate, increasing their levels in blueberries. More volatiles, especially esters, were detected in ethanol-treated blueberries, e.g. methyl acetate, ethyl acetate, ethyl propanoate, ethyl isobutyrate, ethyl 2-methylbutanoate, ethyl isovalerate, ethyl 3-methyl-2-butenoate, diethyl sebacate, and isopropyl myristate. CONCLUSION: The preservative effect of ethanol on blueberry was significantly affected by ethanol concentration. In this study, the effect of 500 µL L-1 ethanol fumigation on blueberry was the best in terms of appearance quality (firmness and decay rate) and flavor attributes (SSC, TA, and volatiles). © 2019 Society of Chemical Industry.


Assuntos
Mirtilos Azuis (Planta)/química , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/efeitos dos fármacos , Mirtilos Azuis (Planta)/efeitos dos fármacos , Frutas/química , Fumigação/métodos , Humanos , Controle de Qualidade , Paladar , Compostos Orgânicos Voláteis/análise
16.
Food Chem ; 299: 125109, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31295635

RESUMO

The aim of this research is to develop, characterize and utilize a multi-layer antibacterial film using chitosan (CS) and sodium alginate (SA) as biopolymers and cinnamon essential oil (CEO) as main antibacterial ingredients. The dense cross-section of SA layer in the scanning electron microscopy (SEM) analysis verified that layer-by-layer method improved physical and mechanical properties of CS-CEO single layer film. The thermogravimetric (TGA) and fourier transform infrared (FT-IR) analysis indicated that the layer-by-layer method changed the intermolecular interaction and the thermal stability. Importantly, the multi-layer film exhibited more sustained release and higher retention rate of CEO compared CS-CEO single layer film. The multi-layer coating showed a more significant and lasting inhibition of penicillium expansion which further demonstrated that the layer-by-layer method improved the release and retention of CEO in the multiphased system. To summarize, the multilayer film system is a promising controllable release system for loading essential oils.


Assuntos
Antifúngicos/farmacologia , Cinnamomum zeylanicum/química , Malus/microbiologia , Óleos Voláteis/farmacologia , Penicillium/efeitos dos fármacos , Alginatos/química , Antifúngicos/química , Quitosana/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Frutas/efeitos dos fármacos , Frutas/microbiologia , Malus/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Óleos Voláteis/farmacocinética , Penicillium/patogenicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria
17.
Food Chem ; 299: 125116, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31295637

RESUMO

The effects of exogenous melatonin treatment on the enzymatic browning and nutritional quality of fresh-cut pear fruit were investigated. Fresh-cut fruit soaked with 0, 0.05, 0.1 and 0.5 mM melatonin were stored at 4 °C. Our results showed that 0.1 mM melatonin treatment was optimal for reducing the surface browning and maintaining the titratable acidity of the fresh-cut fruit, which significantly decreased MDA and H2O2 contents and the growth of microorganism, enhanced total phenolic content and antioxidant capacity, and delayed the reduction of ascorbic acid. Furthermore, melatonin treatment at 0.1 mM decreased the expression of genes involving in enzymatic browning pathway including POD, PPO1, PPO5 and LOX1, and reduced PPO activity. Moreover, this treatment increased the expression of PAL and CHS, and enhanced PAL and CHS activities. These results showed that melatonin treatment might be a promising strategy to alleviate browning and improve the nutritional quality of fresh-cut pear fruit.


Assuntos
Frutas/efeitos dos fármacos , Melatonina/farmacologia , Valor Nutritivo , Pyrus/efeitos dos fármacos , Antioxidantes/análise , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Frutas/microbiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/metabolismo , Malondialdeído/análise , Malondialdeído/metabolismo , Fenóis/análise , Pyrus/química , Pyrus/genética , Pyrus/metabolismo
18.
J Sci Food Agric ; 99(13): 5946-5952, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31206683

RESUMO

BACKGROUND: Grape berries produce significant amounts of phenolic compounds. These are an essential qualitative factor due to their nutritional value and effect on berry color and texture. Salicylic acid (SA) and its derivatives usually lead to enhancement of phenolic content in plant tissues. The present study was conducted to evaluate the effect of different levels of SA (0.0, 50.0, 100.0, and 200.0 mM) on the production of phenolic compounds and the derivatives (anthocyanin and flavonoid) in the grape berries, with emphasis on malvidin-3-O-ß glucoside as a regular anthocyanin in red grapes. RESULT: The results showed that total phenolics content were significantly enhanced in SA-treated (100.0 and 200.0 mM) berries compared to untreated ones. Salicylic acid treatment at all concentrations considerably improved the anthocyanin content in the berries and, compared with untreated berries, the accumulation of malvidin-3-O-ß glucoside was higher in SA-treated fruits. In particular, the 200.0 mM concentration caused approximately two times more malvidin-3-O-ß glucoside than the control. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity of the fruits treated with SA were significantly higher than those of the untreated berries. The activity of phenylalanine ammonia-lyase (PAL) in SA treated fruits significantly increased as compared with the untreated clusters. CONCLUSION: A general evaluation of the current results leads us to the conclusion that SA is a suitable and recommendable treatment for improving and increasing the phenolic and antioxidant capacity of grape berries. Spraying grape berries at pre-véraison stage with SA could therefore be a convenient strategy to increase quality and nutritional value of grape berries considerably. © 2019 Society of Chemical Industry.


Assuntos
Antocianinas/química , Frutas/química , Extratos Vegetais/química , Ácido Salicílico/farmacologia , Vitis/química , Antioxidantes/metabolismo , Cor , Frutas/efeitos dos fármacos , Fenóis/química , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Vitis/efeitos dos fármacos , Vitis/genética
19.
Food Chem ; 297: 124955, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253342

RESUMO

This study aimed to investigate the effect of hydrogen peroxide (H2O2) on membrane lipids metabolism and its relation to pulp breakdown development of longan fruit during postharvest storage. Compared to the control longans, H2O2-treated longans showed higher pulp breakdown index, cell membrane permeability, and activities of phospholipase D (PLD), lipase and lipoxygenase (LOX). Moreover, H2O2-treated longans maintained higher levels of pulp phosphatidic acid (PA) and saturated fatty acids (SFA). However, H2O2-treated longans exhibited lower levels of pulp phosphatidylcholine (PC), phosphatidylinositol (PI) and unsaturated fatty acids (USFA), lower index of unsaturated fatty acids (IUFA), and lower ratio of USFA to SFA (U/S). These findings demonstrated that H2O2 caused the increased activities of enzymes involving in membrane lipids degradation and the accelerated decompositions of membrane USFA and phospholipids in longan pulp, which eventually triggered the destruction of the pulp cell membrane structure and the development of pulp breakdown in longans during storage.


Assuntos
Enzimas/metabolismo , Frutas/química , Peróxido de Hidrogênio/farmacologia , Lipídeos de Membrana/metabolismo , Sapindaceae/química , Enzimas/química , Ácidos Graxos/análise , Ácidos Graxos/química , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Frutas/metabolismo , Peróxido de Hidrogênio/química , Lipase/química , Lipase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoxigenase/química , Lipoxigenase/metabolismo , Lipídeos de Membrana/química , Fosfolipase D/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Sapindaceae/efeitos dos fármacos , Sapindaceae/metabolismo
20.
J Sci Food Agric ; 99(14): 6234-6240, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250461

RESUMO

BACKGROUND: The application of exogenous plant growth regulator, for example forchlorfenuron (CPPU), on kiwifruits has become an important factor that influences kiwifruit economic efficiency and the health development of the kiwifruit industry. Owing to the slight difference in calyx shape between the kiwifruits treated with CPPU (CPPU-treated kiwifruits) and the kiwifruits without CPPU treatment (CPPU-untreated kiwifruits), this study aims to provide a cheap, quick, convenient, and non-destructive method for identifying CPPU-treated kiwifruits based on the images of kiwifruits captured at visible lights. RESULTS: The identification method includes three steps. Firstly, the kiwifruit was extracted from the background by using Otsu algorithm, hole filling operation and 'bwareaopen' function. Secondly, the calyx was extracted by using corrosion, image enhancement, hole filling and closing operations. Finally, the length/width ratio of the minimum enclosing rectangle of calyx region was calculated. The kiwifruit was regarded as a CPPU-treated kiwifruit if the length/width ratio of the rectangle was higher than 1.6. Otherwise, the kiwifruit was regarded as a CPPU-untreated one. The method had the total identification accuracy rate of 90.0% when the kiwifruit images were captured either by utilizing a smartphone at normal lighting condition or by using an image acquisition system. CONCLUSION: The programs run on computer and smartphone were developed, and they could realize kiwifruit identification in 0.6 s and 2 s, respectively. The study makes identifying CPPU-treated kiwifruits in online processing be realizable, and offers a convenient method for kiwifruit consumers. © 2019 Society of Chemical Industry.


Assuntos
Actinidia/efeitos dos fármacos , Resíduos de Drogas/análise , Frutas/química , Fotografação/métodos , Reguladores de Crescimento de Planta/análise , Polietilenoglicóis/análise , Poliuretanos/análise , Actinidia/química , Resíduos de Drogas/farmacologia , Frutas/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Polietilenoglicóis/farmacologia , Poliuretanos/farmacologia , Smartphone
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