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1.
Ecotoxicol Environ Saf ; 203: 110978, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678757

RESUMO

In this study, hydroponic experiments were conducted to elucidate mechanism(s) that are associated with differential effects of low (5 µM) and high (25 µM) dose of cadmium (Cd) stress in tomato. Furthermore, emphasis has also been focused on any involvement of endogenous hydrogen sulfide (H2S) in differential behaviour of low and high doses of Cd stress. At low dose of Cd, root growth i.e. root fresh weight, length and fitness did not significantly alter when compared to the control seedlings. Though at low dose of Cd, cellular accumulation of Cd was slightly increased but this was accompanied by higher endogenous H2S and phytochelatins, L-cysteine desulfhydrase (DES) activity, activities of glutathione biosynthetic and AsA-GSH cycle enzymes, and maintained redox status of ascorbate and glutathione. However, addition of hypotaurine (HT, a scavenger of H2S) resulted in greater toxicity, even at low dose of Cd, and these responses resembled with higher dose of Cd stress such as greater decline in root growth, endogenous H2S and phytochelatins, activities of DES, glutathione biosynthesis and AsA-GSH cycle enzymes, disturbed redox status of ascorbate and glutathione which collectively led to higher oxidative stress in tomato roots. Moreover, addition of HT with higher dose of Cd also further enhanced its toxicity. Collectively, the results showed that differential behaviour of low and high dose of Cd stress is mediated by differential regulation of biochemical attributes in which endogenous H2S has a crucial role.


Assuntos
Cádmio/toxicidade , Sulfeto de Hidrogênio/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Fitoquelatinas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
2.
Aquat Toxicol ; 225: 105552, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32615475

RESUMO

There is scarce investigation addressing interpopulation tolerance responses to address the influence of a history of chronic stress exposure, as that occurring in polluted environments, in photoautotrophs. We evaluated ecophysiological (photosynthetic activity) and metabolic (oxidative stress and damage) responses of two populations of green macroalga Ulva compressa from polluted (Ventanas) and non-polluted (Cachagua) localions of central Chile, and exposed to controlled hypersalinity conditions of 32 (control), 42, 62 and 82 psu (practical salinity units) for 6 h, 48 h and 6 d. Both primary production (ETRmax) and photosynthetic efficiency (αETR) were generally higher in the population from Cachagua compared to Ventanas at all times and salinities. Moreover, at most experimental times and salinities the population from Ventanas had greater levels of H2O2 and lipid peroxidation that individuals from Cachagua. Total ascorbate was higher in the population of Cachagua than Ventanas at 42 and 82 psu after 6 and 48 h, respectively, while at 6 d concentrations were similar between both populations at all salinities. Total glutathione was greater in both populations after 6 h at all salinities, but at 48 h its concentrations were higher only in the population from Cachagua, a trend that was maintained at 6 d under 82 psu only. Reduced and oxidized ascorbate (ASC and DHA, respectively) and glutathione (GSH and GSSG, respectively) demonstrated similar patterns between U. compressa populations, with an increase oxidation with greater salinities but efficient recycling to maintain sufficient batch of ASC and GSH. When assessing the expression of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and dehydroascorbate reductase (DHAR), while the population of Ventanas displayed a general trend of upregulation with increasing salinities along the experiments, U. compressa from Cachagua revealed patterns of downregulation. Results demonstrated that although both populations were still viable after the applied hypersalinities during all experimental times, biological performance was usually more affected in the population from the Ventanas than Cachagua, likely due to a depressed baseline metabolism after a long history of exposition to environmental pollution.


Assuntos
Ulva/fisiologia , Poluentes Químicos da Água/toxicidade , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Chile , Poluição Ambiental , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Oxirredução , Estresse Oxidativo , Salinidade , Alga Marinha/metabolismo , Superóxido Dismutase/metabolismo , Ulva/enzimologia
3.
Food Chem ; 333: 127481, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663753

RESUMO

In this study, we tested the exogenous application of phytosulfokine α (PSKα) for delaying the yellowing of broccoli florets during cold storage. Our results showed that the lower yellowing in broccoli florets treated with 150 nM PSKα was probably due to the higher endogenous accumulation of PSKα, leading to the endogenous accumulation of guanosine 3', 5'-cyclic monophosphate (cGMP). Besides, broccoli florets treated with 150 nM PSKα exhibited a higher accumulation of phenols and flavonoids by triggering gene expression and activities of phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS). Moreover, the higher expression of L-galactotno-1,4-lactone dehydrogenase (GLDH) gene and the lower expression of ascorbic acid oxidase (AAO) gene in broccoli florets treated with 150 nM PSKα may be the reasons for the higher accumulation of ascorbic acid. In conclusion, the exogenous application of PSKα is a promising strategy in delaying the yellowing and preserving the nutritional quality of broccoli florets during cold storage.


Assuntos
Brassica/efeitos dos fármacos , Brassica/metabolismo , Temperatura Baixa , Qualidade dos Alimentos , Armazenamento de Alimentos , Valor Nutritivo/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Ácido Ascórbico/metabolismo , Fenóis/metabolismo , Pigmentação/efeitos dos fármacos
4.
Ecotoxicol Environ Saf ; 201: 110853, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32563160

RESUMO

The phytotoxicity caused by 500 µM ZnSO4.7H2O and its detoxifying by co-application of 100 µM of MT melatonin (MT) and glutathione (GSH) in 6-week-old safflower plants have been investigated. Reduced biomass production and total chlorophyll content on the one hand and increased content of hydrogen peroxide (H2O2), malondialdehyde (MDA) with increase in lipoxygenase activity, on the other hand, showed Zn- induced oxidative damage in safflower seedlings. When MT, GSH and especially MT + GSH exogenously were applied to Zn-stressed seedlings, the content of H2O2, MDA and the activity of lipoxygenase considerably decreased. In Zn- treated seedlings, the application of these signaling molecules led to a considerable increment in ascorbate (ASC), GSH and phytochelatin (PC) contents along with the induction of activity of antioxidant enzymes including ascorbate-glutathione cycle enzymes when compared with the plants stressed with Zn only. In Zn-stressed safflower seedlings treated with MT, GSH and MT + GSH, decreased activity of enzymes involved in glyoxalase system may be associated with the role of MT and GSH in reducing Zn uptake and reducing Zn-induced toxicity and subsequently, lower plant's defense responses. The data showed that the effects of MT and GSH, in particular, the combination of these two molecules in reducing Zn uptake and diminishing its accumulation in the shoots of safflower seedlings, and also the participation of MT and GSH on increasing plant ability to tolerate high amount of Zn through stimulation of various antioxidant defense systems suggest them as suitable candidates to better the survival of safflower in soils contaminated with Zn excess.


Assuntos
Antioxidantes/farmacologia , Carthamus tinctorius/efeitos dos fármacos , Glutationa/farmacologia , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Poluentes do Solo/toxicidade , Zinco/toxicidade , Ácido Ascórbico/metabolismo , Carthamus tinctorius/crescimento & desenvolvimento , Carthamus tinctorius/metabolismo , Clorofila/metabolismo , Sinergismo Farmacológico , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oxirredução , Fitoquelatinas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
5.
Ecotoxicol Environ Saf ; 201: 110823, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540619

RESUMO

This study compared co-tolerance to salinity and cadmium and investigated its mechanisms in a facultative metallophyte Silene vulgaris originating from distinct habitats. Shoots of calamine (Cal) and non-metallicolous (N-Cal) ecotypes grown in vitro were exposed to 10 and 100 mM NaCl, 5 µM CdCl2 and their combinations. Stress effects were evaluated based on growth, oxidative stress parameters, and DNA content and damage. Tolerance mechanisms were assessed by analyzing non-enzymatic antioxidants, osmolytes and ion accumulation. Irrespective of the ecotype, Cd stimulated shoot proliferation (micropropagation coefficients MC = 15.2 and 12.1 for Cal and N-Cal, respectively, growth tolerance index GTI = 148.1 and 156.7%). In Cal ecotype this was attributed to an increase in glutathione content and reorganization of cell membrane structures under Cd exposure, whereas in N-Cal to enhanced synthesis of other non-enzymatic antioxidants, mainly carotenoids and ascorbate. Low salinity stimulated growth of Cal ecotype due to optimizing Cl- content. High salinity inhibited growth, especially in Cal ecotype, where it enhanced DNA damage and disturbed ionic homeostasis. Species-specific reaction to combined salinity and Cd involved a mutual inhibition of Na+, Cl- and Cd2+ uptake. N-Cal ecotype responded to combined stresses by enhancing its antioxidant defense, presumably induced by Cd, whereas the metallicolous ecotype triggered osmotic adjustment. The study revealed that in S. vulgaris Cd application ameliorated metabolic responses to simultaneous salinity exposure. It also shed a light on distinct strategies of coping with combined abiotic stresses in two ecotypes of the species showing high plasticity in environmental conditions.


Assuntos
Adaptação Fisiológica , Cádmio/toxicidade , Dano ao DNA , Estresse Oxidativo/efeitos dos fármacos , Silene/efeitos dos fármacos , Cloreto de Sódio/toxicidade , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Carotenoides/metabolismo , Ecótipo , Glutationa/metabolismo , Estresse Oxidativo/genética , Salinidade , Silene/genética , Silene/crescimento & desenvolvimento , Silene/metabolismo , Solo/química
6.
Food Chem ; 330: 127189, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32521396

RESUMO

The aim of the study was to assess the effect of incandescent, fluorescent, and LED (RGB (red, green, blue), white cold, white warm) lighting on characteristics of kale sprouts. The highest concentrations of chlorophylls, ß-carotene, lutein, neoxanthin and violaxanthin were found in cotyledons of sprouts growing in RGB LED light. These had the largest proportion of cotyledons to the mass of plants and the highest content of ascorbic acid. The highest contents of protein and total thiocyanates were observed in sprouts cultivated in incandescent light, followed by plants growing under RGB LED light. The application of a conventional bulb led to the lowest yield as well as the smallest amounts of chlorophylls, ß-carotene, lutein and neoxanthin in fresh mass of cotyledons. Of the light sources used, RGB LED treatment allowed plants with the highest content of most of the examined compounds to be obtained.


Assuntos
Ácido Ascórbico/metabolismo , Brassica/metabolismo , Pigmentos Biológicos/metabolismo , Tiocianatos/metabolismo , Clorofila/metabolismo , Luz , beta Caroteno/metabolismo
7.
Ecotoxicol Environ Saf ; 200: 110721, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464438

RESUMO

Glutaredoxins (Grxs) are small (10-15 kDa) glutathione (GSH) - dependent redox proteins. The role of Grxs are well documented in tolerance to heavy metal stress in prokaryotic and mammalian systems and a few plant genera, but is poorly understood in plants against drought. In the present study, two rice glutaredoxin (Osgrx) genes (LOC_Os02g40500 and LOC_Os01g27140) responsible for tolerance against heavy metal stress have been studied for investigating their role against drought. Each glutaredoxin gene was over-expressed in Arabidopsis thaliana to reveal their role in drought stress. The relative expression of both Osgrx genes was higher in the transgenic lines. Transgenic lines of both Osgrxs showed longer roots, higher seed germination, and survival efficiency during drought stress. The physiological parameters (PN, gs, E, WUE, qP, NPQ and ETR), antioxidant enzymes (GRX, GR, GPX, GST, APX, POD, SOD, CAT, DHAR, and MDHAR), antioxidant molecules (ascorbate and GSH) and stress-responsive amino acids (cysteine and proline) levels were additionally increased in transgenic lines of both Osgrxs to provide drought tolerance. The outcomes from this study strongly determined that each Osgrx gene participated in the moderation of drought and might be utilized in biological engineering strategies to overcome drought conditions in different crops.


Assuntos
Glutarredoxinas/genética , Oryza/enzimologia , Estresse Fisiológico , Antioxidantes/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Ácido Ascórbico/metabolismo , Cisteína/metabolismo , Secas , Genes de Plantas , Glutarredoxinas/metabolismo , Glutationa/metabolismo , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Prolina/metabolismo , Estresse Fisiológico/genética
8.
Food Chem ; 326: 126966, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32416419

RESUMO

Phenolic compounds and ascorbic acid were analyzed in one yellow and four purple-flesh potato cultivars grown at 13 °C and 18 °C and harvested at different stages of tuber development, using HPLC-DAD and UHPLC-MS. The expression of genes in the phenylpropanoid pathway was studied at transcription level using qPCR. Petunidin-3-p-coumaroylrutinoside-5-glucoside was the most abundant anthocyanin in 'Blue Congo', 'Blaue Schweden', and 'Synkeä Sakari', whereas malvidin-3-p-coumaroylrutinoside-5-glucoside dominated in 'Blaue Veltlin'. In mature tubers, the purple cultivar 'Synkeä Sakari' showed the highest content of anthocyanins (2.4 mg/g freeze-dried sample), and 'Blaue Veltlin' had the highest content of phenolic acids (5.5 mg/g). Cultivar was the main variable affecting the biosynthesis of the studied metabolites, whereas the temperatures studied did not show different impact. The content of the main phenolic acids and anthocyanins in the potato cultivars correlated positively with the expression levels of the genes involved in the phenylpropanoid pathway.


Assuntos
Ácido Ascórbico/metabolismo , Fenóis/metabolismo , Tubérculos/química , Solanum tuberosum/química , Solanum tuberosum/crescimento & desenvolvimento , Antocianinas/metabolismo , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão , Glucosídeos/metabolismo , Espectrometria de Massas , Fenóis/análise , Pigmentação , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Temperatura
9.
PLoS Genet ; 16(5): e1008823, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453789

RESUMO

The development of type 2 diabetes mellitus (T2DM) depends on interactions between genetic and environmental factors, and a better understanding of gene-diet interactions in T2DM will be useful for disease prediction and prevention. Ascorbic acid has been proposed to reduce the risk of T2DM. However, the links between ascorbic acid and metabolic consequences are not fully understood. Here, we report that glucose transporter 10 (GLUT10) maintains intracellular levels of ascorbic acid to promote adipogenesis, white adipose tissue (WAT) development and protect mice from high-fat diet (HFD)-induced metabolic dysregulation. We found genetic polymorphisms in SLC2A10 locus are suggestively associated with a T2DM intermediate phenotype in non-diabetic Han Taiwanese. Additionally, mice carrying an orthologous human Glut10G128E variant (Glut10G128E mice) with compromised GLUT10 function have reduced adipogenesis, reduced WAT development and increased susceptibility to HFD-induced metabolic dysregulation. We further demonstrate that GLUT10 is highly expressed in preadipocytes, where it regulates intracellular ascorbic acid levels and adipogenesis. In this context, GLUT10 increases ascorbic acid-dependent DNA demethylation and the expression of key adipogenic genes, Cebpa and Pparg. Together, our data show GLUT10 regulates adipogenesis via ascorbic acid-dependent DNA demethylation to benefit proper WAT development and protect mice against HFD-induced metabolic dysregulation. Our findings suggest that SLC2A10 may be an important HFD-associated susceptibility locus for T2DM.


Assuntos
Tecido Adiposo Branco/metabolismo , Ácido Ascórbico/metabolismo , Metilação de DNA , Diabetes Mellitus Tipo 2/genética , Dieta Hiperlipídica/efeitos adversos , Proteínas Facilitadoras de Transporte de Glucose/genética , Células 3T3-L1 , Adipogenia , Adulto , Idoso , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Metilação de DNA/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Hemoglobina A Glicada/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mutação , PPAR gama/genética
10.
Ecotoxicol Environ Saf ; 196: 110483, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247238

RESUMO

A study was performed to assess if nitrate reductase (NR) participated in brassinosteroid (BR)-induced cadmium (Cd) stress tolerance primarily by accelerating the ascorbate-glutathione (AsA-GSH) cycle. Prior to initiating Cd stress (CdS), the pepper plants were sprayed with 0.5 µM 24-epibrassinolide (EBR) every other day for 10 days. Thereafter the seedlings were subjected to control or CdS (0.1 mM CdCl2) for four weeks. Cadmium stress decreased the plant growth related attributes, water relations as well as the activities of monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR), but enhanced proline content, leaf Cd2+ content, oxidative stress-related traits, activities of ascorbate peroxidase (APX) and glutathione reductase (GR), and the activities of antioxidant defence system-related enzymes as well as NR activity and endogenous nitric oxide content. EBR reduced leaf Cd2+ content and oxidative stress-related parameters, enhanced plant growth, regulated water relations, and led to further increases in proline content, AsA-GSH cycle-related enzymes' activities, antioxidant defence system-related enzymes as well as NR activity and endogenous nitric oxide content. The EBR and the inhibitor of NR (tungstate) reversed the positive effects of EBR by reducing NO content, showing that NR could be a potential contributor of EBR-induced generation of NO which plays an effective role in tolerance to CdS in pepper plants by accelerating the AsA-GSH cycle and antioxidant enzymes.


Assuntos
Ácido Ascórbico/metabolismo , Brassinosteroides/farmacologia , Cádmio/metabolismo , Glutationa/metabolismo , Nitrato Redutase/metabolismo , Antioxidantes/metabolismo , Cádmio/toxicidade , Capsicum/efeitos dos fármacos , Capsicum/enzimologia , Capsicum/crescimento & desenvolvimento , Capsicum/metabolismo , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Redes e Vias Metabólicas/efeitos dos fármacos , Nitrato Redutase/antagonistas & inibidores , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos
11.
Artigo em Inglês | MEDLINE | ID: mdl-32302942

RESUMO

Involvement of nitrate reductase (NR) and nitric oxide synthase (NOS)-like enzyme in 24-epibrassinolide (EB)-triggered nitric oxide (NO) synthesis to improve iron deficiency (ID) tolerance in strawberry plants was studied. EB was sprayed to strawberry plants every two days for two weeks. Then, the EB-treated plants were pre-treated with inhibitors of NR, tungstate, or NOS, L-NAME for 3 h. During the first three weeks, Fe was supplied as 100 µM EDTA-Fe or FeSO4 to Fe-sufficient or Fe-deficient plants, respectively. Thereafter, plants were subjected for further three weeks to control (100 µM EDTA-Fe) and Fe deficiency (ID; without Fe). ID reduced biomass, chlorophyll, and chlorophyll fluorescence, while increased oxidative stress parameters, ascorbate (AsA), glutathione (GSH), endogenous NO, and the activities of NR, NOS, and antioxidant enzymes. Pre-treatments with EB and EB + SNP improved ID tolerance of strawberry by improving leaf Fe2+, plant growth, and antioxidant enzyme activities, and causing a further elevation in AsA, GSH, NO, NR and NOS. L-NAME application reversed NOS activity, but it did not eliminate NO, however, tungstate application reversed both NR activity and NO synthesis in plants exposed to ID + EB, suggesting that NR is the main contributor of EB-induced NO synthesis to improve ID tolerance in strawberry plants.


Assuntos
Fragaria , Ferro , Nitrato Redutase , Óxido Nítrico , Regulação para Cima , Ácido Ascórbico/metabolismo , Brassinosteroides/farmacologia , Fragaria/efeitos dos fármacos , Fragaria/enzimologia , Fragaria/genética , Regulação da Expressão Gênica de Plantas , Glutationa/metabolismo , Ferro/deficiência , Nitrato Redutase/metabolismo , Óxido Nítrico/biossíntese , Esteroides Heterocíclicos/farmacologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-32302943

RESUMO

L-Ascorbic acid (AsA, vitamin C) is a key antioxidant and enzyme cofactor in plants. Ascorbate controls cell division, affects cell expansion, and plays an important role in modulating plant senescence. It protects plants against reactive oxygen species that are produced in response to abiotic and biotic stresses. Manual phenotyping indicated that Arabidopsis lines over-expressing enzymes in the myo-inositol pathway have elevated AsA, accumulate more biomass of both aerial and root tissues and are tolerant to abiotic stresses including salt, cold, heat, and environmental pollutants. However, manual phenotyping is time consuming, low throughput, subjective, and limited to the resolution of the human eye. In contrast, high throughput phenotyping technologies are accurate, non-destructive, and more sensitive, allowing the detection of subtle phenotypes. Therefore, we used a phenomics platform to phenotype our high AsA Arabidopsis lines with visible, fluorescence, and near infrared cameras. Based on this approach, high AsA lines grew faster, accumulated more biomass, and displayed healthier chlorophyll fluorescence and water content profiles than controls. By studying abiotic stress in a high throughout fashion using optimized protocols, we have also shown that these high AsA lines are tolerant to salt and water limitation stresses. In addition, we developed open source algorithms to analyze images and by comparing results obtained with a widely used commercial software against our algorithms, here we show that our method achieved good accuracy for all phenotypic parameters of interest including projected leaf area, rosette diameter (caliper length), compactness, and color classification.


Assuntos
Arabidopsis , Fenômica , Estresse Fisiológico , Arabidopsis/fisiologia , Ácido Ascórbico/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Estresse Fisiológico/genética
13.
J Oleo Sci ; 69(4): 377-390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32249265

RESUMO

Colletotrichum nymphaeae is the causal agent of strawberry anthracnose, which is one of the most important disease affecting strawberry plant in Iran. This research aimed to apply the selected plant essential oils (EOs) such as Achillea millefolium, Mentha longifolia, and Ferula kuma to the management of strawberry anthracnose disease under in vitro, in vivo, and greenhouse conditions. In vitro tests indicated that all the EOs and fungicide were able to inhibit mycelial growth and conidial germination of the pathogen. Scanning electron microscopy (SEM) revealed that EOs significantly suppressed the mycelia growth and caused a change in morphology of fungal mycelia. The severity of strawberry anthracnose disease was significantly (p ≤ 0.05) reduced by all EOs under in vivo and greenhouse conditions. Results of all experiments showed that M. longifolia EO was the best EO to control C. nymphaeae. Also, EOs almost reduced weight loss and preserved firmness, ascorbic acid, total phenol, antioxidant activity (DPPH), and enzyme peroxidase activity in treated fruit. Moreover, EOs preserved the sensory quality of strawberry fruit during the storage period so that there were no significant differences between treatments (EOs) in their appearance, flavor, odor attributes, and overall evaluation compared to the control. Our results indicate that EOs are excellent bio-fungicides for the management of strawberry anthracnose.


Assuntos
Qualidade dos Alimentos , Fragaria/microbiologia , Fungicidas Industriais , Mentha/química , Óleos Voláteis , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Óleos Vegetais , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Colletotrichum/patogenicidade , Fragaria/metabolismo , Peroxidase/metabolismo , Fenóis/metabolismo
14.
PLoS One ; 15(3): e0230286, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32142558

RESUMO

Circular leaf spot, caused by the ascomycetous fungus Plurivorosphaerella nawae (= Mycosphaerella nawae), is the most problematic fungal disease of persimmon worldwide. In Korea, persimmon exposed to P. nawae inoculum (ascospores) from May to August shows visible circular leaf spot disease symptoms from the end of August to early September. It is important to identify factors affecting this long latent period. The objective of this study was to elucidate the relation between the development of symptom of circular leaf spot and the content of phenolics compounds and vitamin C as well as the antioxidant activities in leaves. Healthy leaves (both young and old) and infected leaves of circular leaf spot-susceptible persimmon cultivar were harvested in 2016. The content of phenolics (total phenols, flavonoids, and tannins) and vitamin C, and their antioxidant activities were analyzed in all types of leaves. Compared with the asymptomatic leaves (old) and the asymptomatic parts of the infected leaves, the symptomatic parts of the infected leaves, symptomatic leaves, and asymptomatic young leaves showed significantly higher content of phenolics and vitamin C, and higher antioxidant activities. Disease incidence and severity were estimated for older leaves (emerged in early May) and younger leaves (emerged at the end of June) in 2017 and 2018. The AUDPC was higher in old leaves than younger leaves. The disease progression was much faster and severe in the older than in the younger leaves. Similar results were found in field experiments. Higher content of phenolics and antioxidant activities in the younger leaves may contribute to circular leaf spot resistance in persimmon. Furthermore, accumulation of phenolics and antioxidant activity in the infected leaves is a post-infection response and the first stage of the defense mechanism.


Assuntos
Diospyros/metabolismo , Imunidade Vegetal , Folhas de Planta/metabolismo , Ascomicetos/patogenicidade , Ácido Ascórbico/metabolismo , Diospyros/imunologia , Diospyros/microbiologia , Flavonoides/metabolismo , Folhas de Planta/microbiologia , Taninos/metabolismo
15.
Food Chem ; 319: 126498, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32169761

RESUMO

Effect of melatonin treatment on visual quality and contents of health-promoting compounds of broccoli florets under room temperature was investigated in the present study. Broccoli florets were treated with 1 µM melatonin and then stored at room temperature. Results showed that melatonin treatment could delay the post-harvest senescence of broccoli, and performed well in maintaining higher levels of antioxidants, such as carotenoids, vitamin C and total phenols, as well as higher antioxidant capacity than the control. Besides, 1 µM melatonin treatment sustained higher content of glucosinolates, and also resulted in increased percentage of the most potent anticarcinogenic profile, glucoraphanin. Further analysis revealed that 1 µM melatonin strongly induced the expression of glucosinolate biosynthesis-related genes BoMYB28, BoMYB34, BoCYP79F1, and BoCYP79B2, as well as BoTGG1, a gene involved in glucosinolate hydrolysis. In conclusion, post-harvest treatment with 1 µM melatonin is potential in maintaining visual quality and health-promoting properties of broccoli florets.


Assuntos
Brassica/efeitos dos fármacos , Melatonina/farmacologia , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Brassica/metabolismo , Carotenoides/metabolismo , Glucosinolatos/metabolismo , Imidoésteres/metabolismo , Fenóis/metabolismo , Temperatura
16.
Chemosphere ; 250: 126308, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32135439

RESUMO

Recently, oilseed rape has gathered interest for its ability to withstand elevated metal contents in plant, a key feature for remediation of contaminated soils. In this study, comparative and functional metabolomic analyses using liquid chromatography/mass spectrometry were undertaken to explore the metabolic basis of this attribute under cadmium (Cd) stress. Results revealed both conserved and differential metabolomic responses between genotype CB671 (tolerant Cd-accumulating) and its sensitive counterpart ZD622. CB671 responded to Cd stress by rearranging carbon flux towards production of compatible solutes, sugar storage forms and ascorbate, as well as jasmonates, ethylene and vitamin B6. Intriguingly, IAA abundance was reduced by 1.91-fold, which was in connection with tryptophan funnelling into serotonin (3.48-fold rise). In ZD622 by contrast, Cd provoked drastic depletion of carbohydrates and vitamins, but subtle hormones alteration. A striking accumulation of unsaturated fatty acids and oxylipins in CB671, paralleled by glycerophospholipids build-up and induction of inositol-derived signalling metabolites (up to 5.41-fold) suggested ability for prompt triggering of detoxifying mechanisms. Concomitantly, phytosteroids, monoterpenes and carotenoids were induced, denoting fine-tuned mechanisms for membrane maintenance, which was not evident in ZD622. Further, ZD622 markedly accumulated phenolics from upstream sub-classes of flavonoids; in CB671 however, a distinct phenolic wiring was activated, prioritizing anthocyanins and lignans instead. Along with cell wall (CW) saccharides, the activation of lignans evoked CW priming in CB671. Current results have demonstrated existence of notable metabolomic-based strategies for Cd tolerance in metal-accumulating oilseed rapes, and provided a holistic view of metabolites potentially contributing to Cd tolerance in this species.


Assuntos
Brassica napus/metabolismo , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Ácido Ascórbico/metabolismo , Brassica napus/genética , Cádmio/análise , Poluição Ambiental/análise , Genótipo , Metabolômica , Raízes de Plantas/metabolismo
17.
Proc Natl Acad Sci U S A ; 117(12): 6484-6490, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32152099

RESUMO

In redox metalloenzymes, the process of electron transfer often involves the concerted movement of a proton. These processes are referred to as proton-coupled electron transfer, and they underpin a wide variety of biological processes, including respiration, energy conversion, photosynthesis, and metalloenzyme catalysis. The mechanisms of proton delivery are incompletely understood, in part due to an absence of information on exact proton locations and hydrogen bonding structures in a bona fide metalloenzyme proton pathway. Here, we present a 2.1-Å neutron crystal structure of the complex formed between a redox metalloenzyme (ascorbate peroxidase) and its reducing substrate (ascorbate). In the neutron structure of the complex, the protonation states of the electron/proton donor (ascorbate) and all of the residues involved in the electron/proton transfer pathway are directly observed. This information sheds light on possible proton movements during heme-catalyzed oxygen activation, as well as on ascorbate oxidation.


Assuntos
Elétrons , Metaloproteínas/química , Prótons , Ascorbato Peroxidases/química , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Catálise , Heme/química , Ligação de Hidrogênio , Metaloproteínas/metabolismo , Modelos Moleculares , Difração de Nêutrons , Oxirredução
18.
Artigo em Inglês | MEDLINE | ID: mdl-32114415

RESUMO

Rice tillering, which determines the panicle number per plant, is an important agronomic trait for grain production. In higher plants, ascorbic acid (Asc) plays a major role in ROS-scavenging activity. l-Galactono-1, 4-lactone dehydrogenase (GalLDH, EC1.3.2.3) is an enzyme that catalyzes the last step of Asc biosynthesis in plants. Previously, we have reported that homozygous L-GalLDH-suppressed transgenic rice plants (GI) display a reduced tiller number and a lower level of foliar carotenoids (Car) compared with wild type. Strigolactones (SL), which play an important role in the suppression of shoot branching, are synthesized in the roots of rice plant using Car as substrates. In this paper, the relationship between Asc, SL, the accumulation of H2O2, changes in antioxidant capacity, enzyme activities, and gene transcriptions related to the synthesis of SL were analyzed in transgenic rice plants for L-GalLDH suppressed (GI-1 and GI-2) and overexpressing (GO-2). The results showed that the altered level of Asc in the L-GalLDH transgenic rice plants leads to a change in redox homeostasis, resulting in a marked accumulation of H2O2 and decreased antioxidant capacity in GI-1 and GI-2, but lower H2O2 content and increased antioxidant capacity in GO-2. Meanwhile, the altered level of Asc also leads to altered enzyme activities and gene transcript abundances related to SL synthesis in L-GalLDH transgenics. These observations support the conclusion that Asc influences tiller number in the L-GalLDH transgenics by affecting H2O2 accumulation and antioxidant capacity, and altering those enzyme activities and gene transcript abundances related to SL synthesis.


Assuntos
Ácido Ascórbico/metabolismo , Regulação da Expressão Gênica de Plantas , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Oryza/metabolismo , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Oryza/enzimologia , Oryza/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-32005398

RESUMO

The nutritional value of a crop lies not only in its protein, lipid, and sugar content but also involves compounds such as the antioxidants lycopene, ß-carotene and vitamin C. In the present study, wild tomato Solanum pimpinellifolium LA 1589 was assessed for its potential to improve antioxidant content. This wild species was found to be a good source of alleles for increasing ß-carotene, lycopene, vitamin C and vitamin E contents in cultivated tomato. Characterization of an LA 1589 interspecific inbred backcross line (IBL) mapping population revealed many individuals with transgressive segregation for the antioxidants confirming the usefulness of this wild species for breeding of these traits. Molecular markers were used to identify QTLs for the metabolites in the IBL population. In total, 64 QTLs were identified for the antioxidants and their locations were compared to the map positions of previously identified QTLs for confirmation. Four (57 %) of the carotenoid QTLs, four (36 %) of the vitamin QTLs, and 11 (25 %) of the phenolic acid QTLs were supported by previous studies. Furthermore, several potential candidate genes were identified for vitamins C and E and phenolic acids loci. These candidate genes might be used as markers in breeding programs to increase tomato's antioxidant content.


Assuntos
Antioxidantes , Frutas/metabolismo , Locos de Características Quantitativas , Solanum/genética , Ácido Ascórbico/genética , Ácido Ascórbico/metabolismo , Carotenoides/metabolismo , Mapeamento Cromossômico , Frutas/genética , Glutationa/genética , Glutationa/metabolismo , Hidroxibenzoatos/metabolismo , Solanum/metabolismo , Vitamina E/genética , Vitamina E/metabolismo
20.
Food Chem ; 316: 126354, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32058195

RESUMO

The study reports shelf-life enhancement of candied mango by infusion of gingerols. Gingerols infused product (GIP), with 3.67 mg gingerols/100 g and non-infused products (control) were packed in multilayer metalized (MET), and ethylene vinyl alcohol (EVOH) based pouches and stored at 25, 35 and 45 °C for 120 days. Degradation kinetics of browning and related parameters showed following order: kß-carotene > ksensory (color) > knon-enzymatic browning > kvitamin C > kantioxidant capacity > k sensory (overall) > ktotal phenolics > kgingerols, resulting in multiple cutoff criteria and predicted shelf-lives (SLpredicted). The application of chemometrics simplified the kinetic interpretations and hence the predictions. Gingerols infusion retarded the deterioration of all quality parameters and substantially enhanced SLpredicted of GIP over control, irrespective of storage conditions. Finally, chemometric based SLpredicted of 144 days closely predicted the actual shelf-life of 142 days for control samples stored in EVOH pouches at 25 °C, in contrast to kinetics based SLpredicted of 185 days.


Assuntos
Catecóis/farmacologia , Álcoois Graxos/farmacologia , Mangifera/efeitos dos fármacos , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Doces , Cor , Armazenamento de Alimentos , Mangifera/metabolismo , Fenóis/metabolismo , beta Caroteno/metabolismo
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