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1.
Nat Prod Res ; 37(14): 2437-2441, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35187999

RESUMO

Virgin Olive Oil (VOO) shelf life is determined by the varietal-specific chemical composition and principally by the of phenolic composition. The aim of this study was to investigate the changes in fatty acid profile, phenolic composition, and quality parameters of nine Italian monovarietal VOOs obtained under the same pedoclimatic, agronomic and technological conditions and stored for 12 months at 15 °C in the dark. The varieties with medium-high concentrations of secoiridoids and balanced values between the individual molecules were those with the highest stability. Orthogonal Projections to Latent Structures (OPLS) regression revealed that oleuropein derivatives and phenolic alcohols had the highest antioxidant activity. OPLS discriminant analysis separated well fresh and stored oils. PV, K270, tyrosol, hydroxytyrosol, and oxidated oleacein were the most effective indicators of VOO ageing. Oleacein and oleocanthal decreased after storage, phenolic alcohols, oleacein and ligstroside aglycon increased.


Assuntos
Antioxidantes , Olea , Azeite de Oliva/análise , Antioxidantes/química , Iridoides/química , Álcoois , Óleos de Plantas/química , Olea/química
2.
Antioxidants (Basel) ; 12(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36670942

RESUMO

The phenolic composition of Syrah and Chardonnay grape pomaces was studied to assess their antioxidant and prooxidant properties. Polyphenols were extracted by a "green" hydroalcoholic solvent (ethanol/water 1:1 v/v), and a detailed chemical and electrochemical characterization of the phenolic compounds was performed. The antioxidant and prooxidant capacity of the pomace was first studied by cyclic voltammetry (CV) and other reference analytical assays, then with biological tests on B16F10 metastatic melanoma cancer cells. Electrochemical data showed that, when a +0.5 V potential was applied, a low to moderate antioxidant capacity was observed. MTT test showed an increasing viability of melanoma cells, after treatments at low concentration (up to 100 µg/mL) and for a short time (6 h), but when cells were treated with higher doses of extract (≥250 µg/mL for 12/24 h), their viability decreased from 25 to 50% vs. control, depending on treatment time, dose, and extract origin. A stronger prooxidant activity resulted when 250 µg/mL of extract was combined with non-toxic doses of H2O2; this activity was correlated with the presence of copper in the extracts. This study shows the potential of winemaking by-products and suggests the opportunity to exploit them for the production of cosmeceuticals, or for combined therapies with approved anticancer drugs.

3.
Antibiotics (Basel) ; 10(9)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34572627

RESUMO

Natural products are being discussed as alternatives to commonly used chemicals in antimicrobial therapy. The study aimed to investigate the antimicrobial activity of propolis against microbial species associated with caries, periodontal disease, and Candida infections. Two commercially available ethanolic extracts of Brazilian and one of European propolis (EEP) were used. The minimal inhibitory concentrations (MIC) of propolis and controls against eight microbial strains were determined. Scanning and transmission electron microscopy (SEM and TEM) images visualized the effect of propolis on microorganisms. Subsequently, the activity on three different multi-species biofilms (both formation and existing biofilms) was assessed. All MIC values of the Brazilian EEPs were low against the tested oral species (≤0.1 mg/mL-3.13 mg/mL propolis (Candida albicans)). The European EEP had slightly higher MICs than the Brazilian EEPs. The SEM and TEM images suggest an interaction of propolis with the microbial cell wall. The European EEP exhibited the strongest effect on retarding biofilm formation, whereas the Brazilian EEPs were highly active against preformed biofilms (100 mg/mL propolis of both EEPs reduced colony forming unit counts always by more than 6 log10). The antimicrobial and anti-biofilm activities point to the potential of propolis as an adjunct in oral health care products.

4.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299248

RESUMO

Parkinson's disease (PD) is a complex and progressive neurodegenerative disorder with a prevalence of approximately 0.5-1% among those aged 65-70 years. Although most of its clinical manifestations are due to a loss of dopaminergic neurons, the PD etiology is largely unknown. PD is caused by a combination of genetic and environmental factors, and the exact interplay between genes and the environment is still debated. Several biological processes have been implicated in PD, including mitochondrial or lysosomal dysfunctions, alteration in protein clearance, and neuroinflammation, but a common molecular mechanism connecting the different cellular alterations remains incompletely understood. Accumulating evidence underlines a significant role of lipids in the pathological pathways leading to PD. Beside the well-described lipid alteration in idiopathic PD, this review summarizes the several lipid alterations observed in experimental models expressing PD-related genes and suggests a possible scenario in relationship to the molecular mechanisms of neuronal toxicity. PD could be considered a lipid-induced proteinopathy, where alteration in lipid composition or metabolism could induce protein alteration-for instance, alpha-synuclein accumulation-and finally neuronal death.


Assuntos
Metabolismo dos Lipídeos/genética , Lipídeos/fisiologia , Doença de Parkinson/genética , Neurônios Dopaminérgicos/metabolismo , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Fosfolipases A2 do Grupo VI/genética , Fosfolipases A2 do Grupo VI/metabolismo , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Degeneração Neural/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
5.
Food Chem ; 300: 125243, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357015

RESUMO

Fatty acids, phenolic compounds, and tocopherols of Coratina, Bosana, Semidana, and Tonda di Cagliari virgin olive oils, were measured over a 45-day harvest period. Phenolic composition was the primary factor distinguishing Bosana, Tonda di Cagliari, and Semidana, whereas fatty acids differentiated Coratina and the other cultivars. Harvest period principally influenced oleacein, oleocanthal, oleuropein and ligstroside aglycones, and flavonoids. High phenolic content was observed for Coratina (1039-688 mg/kg) and Bosana (788-592 mg/kg). A drastic decrease in phenolic content was observed in Semidana (529-134 mg/kg) and Tonda di Cagliari (507-142 mg/kg) during the harvest period. These two cultivars also had low MUFA/PUFA (6.0-4.0 and 4.9-3.2 respectively), suggesting that these varieties should be harvested earlier in the season. These results provide information to producers for improved management of the harvesting process, which is strongly affected by varietal factors.


Assuntos
Análise de Alimentos/métodos , Azeite de Oliva/análise , Azeite de Oliva/química , Agricultura , Aldeídos/análise , Monoterpenos Ciclopentânicos , Ácidos Graxos/análise , Flavonoides/análise , Análise de Alimentos/estatística & dados numéricos , Glucosídeos/análise , Glucosídeos Iridoides , Iridoides/análise , Itália , Olea/química , Fenóis/análise , Piranos/análise , Especificidade da Espécie , Tocoferóis/análise
6.
Molecules ; 24(3)2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30744145

RESUMO

Grape leaves influence several biological activities in the cardiovascular system, acting as antioxidants. In this study, we aimed at evaluating the effect of ethanolic and water extracts from grape leaves grown in Algeria, obtained by accelerator solvent extraction (ASE), on cell proliferation. The amount of total phenols was determined using the modified Folin-Ciocalteu method, antioxidant activities were evaluated by the 2,2-diphenyl-l-picrylhydrazyl free radical (DPPH*) method and ·OH radical scavenging using electron paramagnetic resonance (EPR) spectroscopy methods. Cell proliferation of HepG2 hepatocarcinoma, MCF-7 human breast cancer cells and vein human umbilical (HUVEC) cells, as control for normal cell growth, was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay (MTT). Apoptosis- related genes were determined by measuring Bax and Bcl-2 mRNA expression levels. Accelerator solvent extractor yield did not show significant difference between the two solvents (ethanol and water) (p > 0.05). Total phenolic content of water and ethanolic extracts was 55.41 ± 0.11 and 155.73 ± 1.20 mg of gallic acid equivalents/g of dry weight, respectively. Ethanolic extracts showed larger amounts of total phenols as compared to water extracts and interesting antioxidant activity. HepG2 and MCF-7 cell proliferation decreased with increasing concentration of extracts (0.5, 1, and 2 mg/mL) added to the culture during a period of 1⁻72 h. In addition, the expression of the pro-apoptotic gene Bax was increased and that of the anti-apoptotic gene Bcl-2 was decreased in a dose-dependent manner, when both MCF-7 and HepG2 cells were cultured with one of the two extracts for 72 h. None of the extracts elicited toxic effects on vein umbilical HUVEC cells, highlighting the high specificity of the antiproliferative effect, targeting only cancer cells. Finally, our results suggested that ASE crude extract from grape leaves represents a source of bioactive compounds such as phenols, with potential antioxidants activity, disclosing a novel antiproliferative effect affecting only HepG2 and MCF-7 tumor cells.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Vitis/química , Antioxidantes/química , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Concentração Inibidora 50 , Células MCF-7 , Fenóis/química , Extratos Vegetais/química
7.
Radiol Med ; 123(3): 191-201, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29119524

RESUMO

PURPOSE: To assess the variability of radiation dose exposure in patients affected by lymphoma undergoing repeat CT (computed tomography) examinations and to evaluate the influence of different scan parameters on the overall radiation dose. MATERIALS AND METHODS: A series of 34 patients (12 men and 22 women with a median age of 34.4 years) with lymphoma, after the initial staging CT underwent repeat follow-up CT examinations. For each patient and each repeat examination, age, sex, use of AEC system (Automated Exposure Control, i.e. current modulation), scan length, kV value, number of acquired scans (i.e. number of phases), abdominal size diameter and dose length product (DLP) were recorded. The radiation dose of just one venous phase was singled out from the DLP of the entire examination. All scan data were retrieved by our PACS (Picture Archiving and Communication System) by means of a dose monitoring software. RESULTS: Among the variables we considered, no significant difference of radiation dose was observed among patients of different ages nor concerning tube voltage. On the contrary the dose delivered to the patients varied depending on sex, scan length and usage of AEC. No significant difference was observed depending on the behaviour of technologists, while radiologists' choices had indirectly an impact on the radiation dose due to the different number of scans requested by each of them. CONCLUSIONS: Our results demonstrate that patients affected by lymphoma who undergo repeat whole body CT scanning may receive unnecessary overexposure. We quantified and analyzed the most relevant variables in order to provide a useful tool to manage properly CT dose variability, estimating the amount of additional radiation dose for every single significant variable. Additional scans, incorrect scan length and incorrect usage of AEC system are the most relevant cause of patient radiation exposure.


Assuntos
Expectativa de Vida , Linfoma/diagnóstico por imagem , Exposição à Radiação/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Doses de Radiação , Exposição à Radiação/prevenção & controle , Estudos Retrospectivos
8.
J Agric Food Chem ; 65(8): 1829-1835, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28190357

RESUMO

The amount and composition of the phenolic components play a major role in determining the quality of olive oil. The traditional liquid-liquid extraction (LLE) method requires a time-consuming sample preparation to obtain the "phenolic profile" of extra virgin olive oil (EVOO). This study aimed to develop a microdialysis extraction (MDE) as an alternative to the LLE method to evaluate the phenolic components of EVOO. To this purpose, a microdialysis device and dialysis procedure were developed. "Dynamic-oil" microdialysis was performed using an extracting solution (80:20 methanol/water) flow rate of 2 µL min-1 and a constant EVOO stream of 4 µL min-1. The results indicated a strong positive correlation between MDE and the LLE method, providing a very similar phenolic profile obtained with traditional LLE. In conclusion, the MDE approach, easier and quicker in comparison to LLE, provided a reliable procedure to determine the phenolic components used as a marker of the quality and traceability of EVOO.


Assuntos
Microdiálise/métodos , Olea/química , Azeite de Oliva/isolamento & purificação , Fenóis/química , Extratos Vegetais/isolamento & purificação , Microdiálise/instrumentação , Azeite de Oliva/química , Fenóis/isolamento & purificação , Extratos Vegetais/química
9.
Bioorg Med Chem ; 24(21): 5291-5301, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27624523

RESUMO

Pyrazolo[5,1-f][1,6]naphthyridine-carboxamide derivatives were synthesized and evaluated for the affinity at CB1 and CB2 receptors. Based on the AgOTf and proline-cocatalyzed multicomponent methodology, the ethyl 5-(p-tolyl)pyrazolo[5,1-f][1,6]naphthyridine-2-carboxylate (12) and ethyl 5-(2,4-dichlorophenyl)pyrazolo[5,1-f][1,6]naphthyridine-2-carboxylate (13) intermediates were synthesized from the appropriate o-alkynylaldehydes, p-toluenesulfonyl hydrazide and ethyl pyruvate. Most of the novel compounds feature a p-tolyl (8a-i) or a 2,4-dichlorophenyl (8j) motif at the C5-position of the tricyclic pyrazolo[5,1-f][1,6]naphthyridine scaffold. Structural variation on the carboxamide moiety at the C2-position includes basic monocyclic, terpenoid and adamantine-based amines. Among these derivatives, compound 8h (N-adamant-1-yl-5-(p-tolyl)pyrazolo[5,1-f][1,6]naphthyridine-2-carboxamide) exhibited the highest CB2 receptor affinity (Ki=33nM) and a high degree of selectivity (KiCB1/KiCB2=173:1), whereas a similar trend in the near nM range was seen for the bornyl analogue (compound 8f, Ki=53nM) and the myrtanyl derivative 8j (Ki=67nM). Effects of 8h, 8f and 8j on forskolin-stimulated cAMP levels were determined, showing antagonist/inverse agonist properties for such compounds. Docking studies conducted for these derivatives and the reference antagonist/inverse agonist compound 4 (SR144528) disclosed the specific pattern of interactions probably related to the pyrazolo[5,1-f][1,6]naphthyridine scaffold as CB2 inverse agonists.


Assuntos
Modelos Moleculares , Naftiridinas/química , Naftiridinas/farmacologia , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/antagonistas & inibidores , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Naftiridinas/síntese química , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Relação Estrutura-Atividade
10.
J Chromatogr A ; 1467: 228-238, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27328882

RESUMO

Although the halogen bond (XB) has been so far mainly studied in silico and in the solid state, its potential impact in solution is yet to be fully understood. In this study, we describe the first systematic investigation on the halogen bond in solvated environment by high-performance liquid chromatography (HPLC). Thirty three atropisomeric polyhalogenated-4,4'-bipyridines (HBipys), containing Cl, Br and I as substituents, were selected and used as potential XB donors (XBDs) on two cellulose-based chiral stationary phases (CSPs) containing potential XB acceptors (XBAs). The impact of the halogens on the enantiodiscrimination mechanism was investigated and iodine showed a pivotal role on the enantioseparation in non-polar medium. Electrostatic potentials (EPs) were computed to understand the electrostatic component of CSP-analyte interaction. Moreover, van't Hoff studies for ten HBipys were performed and the thermodynamic parameters governing the halogen-dependent enantioseparations are discussed. Finally, a molecular dynamic (MD) simulation is proposed to model halogen bond in polysaccharide-analyte complexes by inclusion of a charged extra point to represent the positive 'σ-hole' on the halogen atom. On the basis of both experimental results and theoretical data, we have profiled the halogen bond as a chemo-, regio-, site- and stereoselective interaction which can work in HPLC environment besides other known interactions based on the complementarity between selector and selectand.


Assuntos
Cromatografia Líquida de Alta Pressão , Halogênios/química , Celulose/química , Polissacarídeos/química , Eletricidade Estática , Termodinâmica
11.
Eur J Med Chem ; 85: 747-57, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25134064

RESUMO

A series of dihydrothienocyclopentapyrazole-based derivatives was synthesized and evaluated for the affinity at CB1 and CB2 receptors. The major term, the 6-methyl-1-(1,4-dichlorophenyl)-N-piperidinyl)-1,4-dihydrothieno[2',3'-4,5]cyclopenta[1,2-c]pyrazole-3-carboxamide (6a), displayed a high affinity and good selectivity for CB2 receptors (Ki values of 2.30 nM for CB2 receptor and 440 nM for CB1 receptors respectively). Subsequent analogue preparation resulted in the identification of compounds such as 6b, 6d, 6e, 6k, 6l, 6m, 6s and 6t that showed 1.3-485 fold selectivity for CB2 receptors with potencies in the 1.1-7.2 nM range. These compounds profiled as full agonists at CB2 receptor in an inhibition assay of P-ERK 1/2 up regulation in HL-60 cells.


Assuntos
Desenho de Fármacos , Pirazóis/química , Pirazóis/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Células HL-60 , Humanos , Ligantes , Ligação Proteica , Pirazóis/síntese química , Especificidade por Substrato
12.
Eur J Med Chem ; 84: 181-93, 2014 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-25016376

RESUMO

Novel pyrazolo[5,1-f][1,6]naphthyridines, pyrazolo[5,1-a][2,6]naphthyridines, pyrazolo[5,1-a][2,7]naphthyridines and pyrazolo[5,1-a]isoquinolines phenylimidazole/benzimidazole ethylene-linked were designed and synthesized for PDE10A interaction. An AgOTf and proline-cocatalyzed multicomponent methodology based on use of o-alkynylaldehydes, tosylhydrazide and ketones was developed and proved to be a convenient route for assembly of most of the novel tricyclic pyrazoles synthesized. Pyrazolo[5,1-f][1,6]naphthyridine 43 and 59, pyrazolo[5,1-a][2,6]naphthyridine 66, and pyrazolo[5,1-a][2,7]naphthyridine 42 showed the highest affinity for PDE10A enzyme (IC50 = 40, 42, 40, 55 nM, respectively).


Assuntos
Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Pirazóis/farmacologia , Animais , Relação Dose-Resposta a Droga , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Modelos Moleculares , Estrutura Molecular , Inibidores de Fosfodiesterase/química , Pirazóis/síntese química , Pirazóis/química , Ratos , Relação Estrutura-Atividade
13.
Recent Pat CNS Drug Discov ; 8(1): 42-69, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23477308

RESUMO

The search of new drugs and targets to treat the pain is an intriguing challenge both for several companies and researchers from academia. In this context, since the modulation of the endocannabinoid system with the non selective phytocannabinoid Δ9-THC produces analgesia and potentiates opioid analgesia in animal models, CB2 ligands studies aimed to explore the involvement of endocannabinoid system in management of pain were started. Several selective CB2 receptor agonists exhibited analgesic activity in preclinical models of acute, inflammatory and neuropathic pain, therefore this class of modulators could be useful as analgesic agents for pain, migraine, inflammation and osteoarthritis. This review is an update of our previously manuscript "A survey of recent patents on CB2 agonists in the management of pain" and provides an overview of patents and advances in CB2 agonist studies in the treatment of pain.


Assuntos
Analgésicos não Narcóticos/classificação , Analgésicos não Narcóticos/uso terapêutico , Dor/tratamento farmacológico , Receptor CB2 de Canabinoide/agonistas , Analgésicos não Narcóticos/química , Animais , Humanos , Ligantes , Estrutura Molecular , Dor/metabolismo , Patentes como Assunto , Receptor CB2 de Canabinoide/metabolismo , Relação Estrutura-Atividade
14.
J Agric Food Chem ; 58(12): 7297-304, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20486661

RESUMO

Imazalil (IMZ) was quantified in the flavedo and albedo (Citrus fruits outer and inner tissue of the exocarp) of wounded and unwounded Valencia L. Olinda oranges following a 2 min immersion at 25 degrees C in 50, 100, or 250 microg mL(-1) of the fungicide mixture with or without 3% sodium bicarbonate (SBC). The addition of SBC significantly reduced the decay incidence throughout 30 d of storage at 10 degrees C with 95% RH and 6 d of simulated marketing period at 25 degrees C and 75% RH. In unwounded oranges, IMZ uptake was not changed by the coapplication of SBC, and the fungicide was predominantly recovered in the flavedo. To the contrary, in the albedo of wounded fruit, the residue level increased by about 6-fold when the fungicide was applied with SBC. When SBC was coapplied to wounded fruit, the phytoalexin scoparone was induced in the albedo and the accumulation was not affected by IMZ. When fruit was treated with SBC, scanning electron microscopy observations evidenced a production of crystalline wax patches with branched stripes and the magnitude was positively correlated to the salt concentration in the mixture. The generation as fast as 24 h post-treatment, and the different morphology of the new wax suggests a displacement of intracuticular waxes which can affect the fungicide sorption and diffusion coefficient into the rind.


Assuntos
Citrus sinensis/efeitos dos fármacos , Conservação de Alimentos/métodos , Fungicidas Industriais/análise , Imidazóis/análise , Penicillium/fisiologia , Bicarbonato de Sódio/farmacologia , Citrus sinensis/química , Citrus sinensis/microbiologia , Frutas/química , Frutas/efeitos dos fármacos , Frutas/microbiologia , Fungicidas Industriais/farmacologia , Imidazóis/farmacologia , Penicillium/efeitos dos fármacos , Ceras/análise
15.
J Agric Food Chem ; 57(2): 623-31, 2009 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-19123818

RESUMO

The influence of the immersion of lemon fruit in aqueous imazalil (IMZ) mixtures at 25 or 50 degrees C on the deposition and persistence of IMZ within the fruit rind and its effectiveness in controlling postharvest green mold, caused by Penicillium digitatum, was investigated. Concentrations of IMZ in the albedo tissue surrounding deep wounds in the rind were higher than the mean EC50 values for IMZ-resistant strains (1.0 microg *mL(-1)) after immersion of fruit into IMZ mixtures containing 25, 50, or 75 mg* L(-1) heated to 50 degrees C, but not those at 25 degrees C, where fungicide deposition was insufficient. IMZ residue, one day after treatment with 25, 50, or 75 mg* L(-1), was 3, 5, or 7 times higher after treatment at 50 degrees C compared to treatment at 25 degrees C. IMZ residues within the albedo of unwounded fruit treated with 25, 50, or 75 mg* L(-1) at 50 degrees C were 0.8, 1.3, or 2.0 microg * g(-1), respectively, while those similarly treated at 25 degrees C had negligible residues. Residues following treatment at 50 degrees C in the albedo did not decline during storage at 10 degrees C after 60 days. IMZ residues in the flavedo were higher than those in the albedo: after treatment with 25, 50, or 75 mg* L(-1) IMZ, they averaged 1.0, 1.2, or 2.7 microg * g(-1), respectively, after treatment at 25 degrees C, and 5.5, 7.9, or 16.2 microg * g(-1), respectively, after treatment at 50 degrees C. IMZ effectiveness as an eradicant to control green mold improved when it was heated. Green mold was reduced by 22 or 95% after treatment of lemons inoculated 1 h before immersion of lemons in IMZ at 50 mg* L(-1) at 25 or 50 degrees C, respectively. Green mold was reduced by 18 or 61% after treatment of lemons inoculated 1 day after immersion of lemons in IMZ at 50 mg* L(-1) at 25 or 50 degrees C, respectively. Scanning electron microscopy of the rind surface indicated that treatment at 50 degrees C for 2 min also caused ruptures in the cuticle.


Assuntos
Antifúngicos/farmacologia , Citrus/efeitos dos fármacos , Imidazóis/farmacologia , Penicillium/efeitos dos fármacos , Doenças das Plantas/microbiologia , Citrus/química , Citrus/microbiologia , Conservação de Alimentos , Temperatura
16.
J Agric Food Chem ; 53(9): 3510-8, 2005 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-15853395

RESUMO

Following sodium carbonate treatment, accumulation of scoparone (6,7-dimethoxycoumarin) but not scopoletin (6-methoxy-7-hydroxycoumarin) was found in the albedo of wounded fruit from different Citrus sp. and cultivars. Treating wounded mandarin fruit cv. Fairchild with 5% Na(2)CO(3) (SC) lead to a scoparone accumulation in the albedo of 310, 361, and 382 microg g(-1) fresh weight after 7, 10, and 15 days, respectively. Scoparone accumulation was associated with a decrease in decay severity. When oranges cv. Biondo comune wounded and treated with 5% SC were inoculated with Penicillium digitatum or Penicillium italicum conidia 3 days posttreatment, the decay percentage as compared to untreated wounds was reduced by 97.2 and 93.9%, respectively. Observations by scanning electron microscopy of wounded Citrus fruits treated at 20 degrees C with 2, 3, 4, or 5% (w/v) solutions of sodium carbonate showed structural modifications to the albedo as well as damage to 24-48 h old mycelia of P. digitatum, the cause of citrus green mold. Modifications were more evident in orange, lemon, and grapefruit as compared to mandarin fruit. The efficacy of the treatment was strictly related to the SC interaction with the albedo tissue that, in addition to structural changes, significantly increased tissue pH, affecting P. digitatum pathogenicity. The SC remaining as a film on unwounded flavedo had no effect in preventing contact infection by the Penicillia.


Assuntos
Carbonatos/farmacologia , Citrus/metabolismo , Cumarínicos/metabolismo , Frutas/efeitos dos fármacos , Frutas/metabolismo , Citrus/microbiologia , Frutas/ultraestrutura , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Penicillium , Doenças das Plantas/microbiologia
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