Base de dados : MEDLINE
Pesquisa : D10.945 [Categoria DeCS]
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  1 / 3209 MEDLINE  
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[PMID]:29337670
[Au] Autor:Hanif M; Khan HU; Afzal S; Mahmood A; Maheen S; Afzal K; Iqbal N; Andleeb M; Abbas N
[Ad] Endereço:1Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan.
[Ti] Título:Sustained release biodegradable solid lipid microparticles: Formulation, evaluation and statistical optimization by response surface methodology.
[So] Source:Acta Pharm;67(4):441-461, 2017 Dec 20.
[Is] ISSN:1846-9558
[Cp] País de publicação:Croatia
[La] Idioma:eng
[Ab] Resumo:For preparing nebivolol loaded solid lipid microparticles (SLMs) by the solvent evaporation microencapsulation process from carnauba wax and glyceryl monostearate, central composite design was used to study the impact of independent variables on yield (Y1), entrapment efficiency (Y2) and drug release (Y3). SLMs having a 10-40 µm size range, with good rheological behavior and spherical smooth surfaces, were produced. Fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray diffractometry pointed to compatibility between formulation components and the zeta-potential study confirmed better stability due to the presence of negative charge (-20 to -40 mV). The obtained outcomes for Y1 (29-86 %), Y2 (45-83 %) and Y3 (49-86 %) were analyzed by polynomial equations and the suggested quadratic model were validated. Nebivolol release from SLMs at pH 1.2 and 6.8 was significantly (p < 0.05) affected by lipid concentration. The release mechanism followed Higuchi and zero order models, while n > 0.85 value (Korsmeyer- Peppas) suggested slow erosion along with diffusion. The optimized SLMs have the potential to improve nebivolol oral bioavailability.
[Mh] Termos MeSH primário: Preparações de Ação Retardada/química
Composição de Medicamentos/métodos
Glicerídeos/química
Ceras/química
[Mh] Termos MeSH secundário: Calorimetria/métodos
Portadores de Fármacos/química
Nebivolol/farmacocinética
Tamanho da Partícula
Espectroscopia de Infravermelho com Transformada de Fourier
Propriedades de Superfície
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Delayed-Action Preparations); 0 (Drug Carriers); 0 (Glycerides); 0 (Waxes); 030Y90569U (Nebivolol); 230OU9XXE4 (glyceryl monostearate); R12CBM0EIZ (carnauba wax)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180131
[Lr] Data última revisão:
180131
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE


  2 / 3209 MEDLINE  
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[PMID]:28460081
[Au] Autor:Lihavainen J; Ahonen V; Keski-Saari S; Sõber A; Oksanen E; Keinänen M
[Ad] Endereço:Department of Environmental and Biological Sciences, University of Eastern Finland, PO Box 111, 80101 Joensuu, Finland.
[Ti] Título:Low vapor pressure deficit reduces glandular trichome density and modifies the chemical composition of cuticular waxes in silver birch leaves.
[So] Source:Tree Physiol;37(9):1166-1181, 2017 Sep 01.
[Is] ISSN:1758-4469
[Cp] País de publicação:Canada
[La] Idioma:eng
[Ab] Resumo:Cuticular wax layer is the first barrier against the outside environment and the first defense encountered by herbivores and pathogens. The effects of environmental factors on cuticular chemistry, and on the formation of glandular trichomes that account for the storage and secretion of lipophilic compounds to the leaf surface are poorly understood. Low vapor pressure deficit (VPD) has shown to reduce the nitrogen (N) status of plants. Thus, we studied the effects of elevated air humidity, indicated as VPD, and the effect of N fertilization on cuticular waxes and glandular trichome density in silver birch (Betula pendula Roth). Experiments were carried out in growth chambers with juvenile plants and in a long-term field experiment with older trees. Low VPD reduced the glandular trichome density in both experiments, in chamber and in field. The contents of the major triterpenoid and flavonoid aglycones correlated positively with glandular trichome density, which supports the role of trichomes in the exudation of secondary compounds to the leaf surface. A closer examination of the cuticular wax chemistry in the chamber experiment revealed that low VPD and N supply affected the composition of cuticular waxes, but not the total wax content. The deposition of different wax compounds followed a co-ordinated pattern in birch leaves, but different compound groups varied in their responses to N fertilization and low VPD. Low VPD reduced the hydrophobicity of cuticular waxes, as demonstrated by lower alkane content and less hydrophobic flavonoid profile in low VPD than in high VPD. Reduced hydrophobicity of the wax layer is presumed to increase leaf wettability. Together with reduced trichome density in low VPD it may enhance the susceptibility of trees to fungal pathogens and herbivores. High N supply under low VPD reduced the effect of low VPD on the cuticular wax composition. Total fatty acid content and the expression of ß-amyrin synthase were lower under high N supply than under moderate N supply irrespective of VPD treatment. Nitrogen availability and decreasing VPD will modify leaf surface properties in silver birch and thereby affect tree defence against abiotic and biotic stress factors that emerge under climate change.
[Mh] Termos MeSH primário: Betula/fisiologia
Folhas de Planta/química
Tricomas/fisiologia
Pressão de Vapor
Ceras/química
[Mh] Termos MeSH secundário: Mudança Climática
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Waxes)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180115
[Lr] Data última revisão:
180115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1093/treephys/tpx045


  3 / 3209 MEDLINE  
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[PMID]:28873623
[Au] Autor:Kowalski RJ; Hause JP; Joyner Melito H; Ganjyal GM
[Ad] Endereço:School of Food Science, Washington State University, Pullman, WA 99164, USA.
[Ti] Título:Waxy flour degradation - Impact of screw geometry and specific mechanical energy in a co-rotating twin screw extruder.
[So] Source:Food Chem;239:688-696, 2018 Jan 15.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Dextrinization of starch using extrusion processing is crucial to the quality of direct expanded products. To determine the extent of dextrinization, flour samples were extracted from a twin-screw extruder that had been brought to a sudden stop and molecular weights were determined by intrinsic viscosity. The screw profile and moisture feed content had the most significant impact on molecular weight reduction, reducing intrinsic viscosity from 1.75 to 0.70dL/g at the most. The breakdown, as shown by a reduction in intrinsic viscosity, had a strong negative correlation (r=-0.96) with specific mechanical energy. However, the extruder die did not have a measurable impact on the molecular weight reduction of waxy flour. Size exclusion chromatography confirmed intrinsic viscosity measurements were associated with reduction of the size of amylopectin molecules to approximately 1/10 the original molecular weight while native gliadin was nearly eliminated from the waxy flour following the extrusion treatments.
[Mh] Termos MeSH primário: Farinha
[Mh] Termos MeSH secundário: Parafusos Ósseos
Amido
Viscosidade
Ceras
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Waxes); 9005-25-8 (Starch)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170907
[St] Status:MEDLINE


  4 / 3209 MEDLINE  
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[PMID]:28873622
[Au] Autor:Chu W; Gao H; Chen H; Fang X; Zheng Y
[Ad] Endereço:College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China; Food Science Institute, Zhejiang Academy of Agricultural Science, Key Laboratory of Post-Harvest Handling of Fruits, Ministry of Agriculture, Key Laboratory of Fruits and Vegetables Postharvest and Proces
[Ti] Título:Effects of cuticular wax on the postharvest quality of blueberry fruit.
[So] Source:Food Chem;239:68-74, 2018 Jan 15.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The blueberry fruit has a light-blue appearance because its blue-black skin is covered with a waxy bloom. This layer is easily damaged or removed during fruit harvesting and postharvest handling. We investigated the effects of wax removal on the postharvest quality of blueberry fruit and their possible mechanisms. The removal of natural wax on the fruit was found to accelerate the postharvest water loss and decay, reduce the sensory and nutritional qualities, and shorten the shelf-life. Wax removal decreased the activities of antioxidant enzymes and contents of antioxidants, and accelerated accumulation of ROS and lipid peroxidation, especially at the later period of storage. Moreover, the organellar membrane structure was disrupted in fruit with wax removed. These results indicate that cuticular wax plays an important role in maintaining the postharvest quality and delaying fruit senescence. The results should improve our understanding for better preservation of postharvest quality of blueberry fruit.
[Mh] Termos MeSH primário: Mirtilos Azuis (Planta)
[Mh] Termos MeSH secundário: Antioxidantes
Conservação de Alimentos
Frutas
Valor Nutritivo
Ceras
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antioxidants); 0 (Waxes)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170907
[St] Status:MEDLINE


  5 / 3209 MEDLINE  
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[PMID]:29073205
[Au] Autor:Hao S; Ma Y; Zhao S; Ji Q; Zhang K; Yang M; Yao Y
[Ad] Endereço:Beijing Key Laboratory of New Technology in Agriculture Application, Plant Science and Technology College, Beijing University of Agriculture, Beijing, China.
[Ti] Título:McWRI1, a transcription factor of the AP2/SHEN family, regulates the biosynthesis of the cuticular waxes on the apple fruit surface under low temperature.
[So] Source:PLoS One;12(10):e0186996, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cuticular waxes of plant and organ surfaces play an important role in protecting plants from biotic and abiotic stress and extending the freshness, storage time and shelf life in the post-harvest agricultural products. WRI1, a transcription factor of AP2/SHEN families, had been found to trigger the related genes taking part in the biosynthesis of seed oil in many plants. But whether WRI1 is involved in the biosynthesis of the cuticular waxes on the Malus fruits surface has been unclear. We investigated the changes of wax composition and structure, the related genes and WRI1 expression on Malus asiatica Nakai and sieversii fruits with the low temperature treatments, found that low temperature induced the up-regulated expression of McWRI1, which promoted gene expression of McKCS, McLACs and McWAX in very-long-chain fatty acid biosynthesis pathway, resulting in the accumulation of alkanes component and alteration of wax structure on the fruit surface. Corresponding results were verified in McWRI1 silenced by VIGS, and WRI1 silenced down-regulated the related genes on two kinds of fruits, it caused the diversity alteration in content of some alkanes, fatty acid and ester component in two kinds of fruits. We further conducted Y1H assay to find that McWRI1 transcription factor activated the promoter of McKCS, McLAC and McWAX to regulate their expression. These results demonstrated that McWRI1 is involved in regulating the genes related synthesis of very long chain fatty acid on surface of apple fruits in storage process, providing a highlight for improvement of the modified atmosphere storage of apple fruits.
[Mh] Termos MeSH primário: Frutas/metabolismo
Malus/metabolismo
Proteínas de Plantas/metabolismo
Temperatura Ambiente
Fatores de Transcrição/metabolismo
Ceras/metabolismo
[Mh] Termos MeSH secundário: Clonagem Molecular
DNA Complementar/genética
Frutas/genética
Regulação da Expressão Gênica de Plantas
Inativação Gênica
Malus/genética
Malus/fisiologia
Mutação
Proteínas de Plantas/genética
Regiões Promotoras Genéticas/genética
Estresse Fisiológico/genética
Fatores de Transcrição/deficiência
Fatores de Transcrição/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (Plant Proteins); 0 (Transcription Factors); 0 (Waxes)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171110
[Lr] Data última revisão:
171110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171027
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186996


  6 / 3209 MEDLINE  
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[PMID]:28789996
[Au] Autor:Petry T; Bury D; Fautz R; Hauser M; Huber B; Markowetz A; Mishra S; Rettinger K; Schuh W; Teichert T
[Ad] Endereço:ToxMinds B.V.B.A., Avenue de Broqueville 116, B-1200 Brussels, Belgium. Electronic address: thomas.petry@toxminds.com.
[Ti] Título:Review of data on the dermal penetration of mineral oils and waxes used in cosmetic applications.
[So] Source:Toxicol Lett;280:70-78, 2017 Oct 05.
[Is] ISSN:1879-3169
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Mineral oils and waxes used in cosmetic products, also referred to as "personal care products" outside the European Union, are mixtures of predominantly saturated hydrocarbons consisting of straight-chain, branched and ring structures with carbon chain lengths greater than C16. They are used in skin and lip care cosmetic products due to their excellent skin tolerance as well as their high protecting and cleansing performance and broad viscosity options. Recently, concerns have been raised regarding potential adverse health effects of mineral oils and waxes from dermal application of cosmetics. In order to be able to assess the risk for the consumer the dermal penetration potential of these ingredients has to be evaluated. The scope and objective of this review are to identify and summarize publicly available literature on the dermal penetration of mineral oils and waxes as used in cosmetic products. For this purpose, a comprehensive literature search was conducted. A total of 13 in vivo (human, animal) and in vitro studies investigating the dermal penetration of mineral oils and waxes has been identified and analysed. The majority of the substances were dermally adsorbed to the stratum corneum and only a minor fraction reached deeper skin layers. Overall, there is no evidence from the various studies that mineral oils and waxes are percutaneously absorbed and become systemically available. Thus, given the absence of dermal uptake, mineral oils and waxes as used in cosmetic products do not present a risk to the health of the consumer.
[Mh] Termos MeSH primário: Cosméticos/toxicidade
Óleo Mineral/farmacocinética
Óleo Mineral/toxicidade
Absorção Cutânea
Ceras/farmacocinética
Ceras/toxicidade
[Mh] Termos MeSH secundário: Seres Humanos
Óleo Mineral/química
Ceras/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Cosmetics); 0 (Waxes); 8020-83-5 (Mineral Oil)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170810
[St] Status:MEDLINE


  7 / 3209 MEDLINE  
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[PMID]:28768926
[Au] Autor:Shiino K; Fujinami Y; Kimura SI; Iwao Y; Noguchi S; Itai S
[Ad] Endereço:Department of Pharmaceutical Engineering, School of Pharmaceutical Sciences, University of Shizuoka.
[Ti] Título:Melt Adsorption as a Manufacturing Method for Fine Particles of Wax Matrices without Any Agglomerates.
[So] Source:Chem Pharm Bull (Tokyo);65(8):726-731, 2017.
[Is] ISSN:1347-5223
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:We have focused on melt adsorption as manufacture method of wax matrices to control particles size of granules more easily than melt granulation. The purpose of present study was to investigate the possibility of identifying a hydrophobic material with a low melting point, currently used as a meltable binder of melt granulation, to apply as a novel carrier in melt adsorption. Glyceryl monostearate (GM) and stearic acid (SA) were selected as candidate hydrophobic materials with low melting points. Neusilin US2 (US2), with a particle diameter of around 100 µm was selected as a surface adsorbent, while dibasic calcium phosphate dihydrate (DCPD), was used as a non-adsorbent control to prepare melting granules as a standard for comparison. We prepared granules containing ibuprofen (IBU) by melt adsorption or melt granulation and evaluated the particle size, physical properties and crystallinity of granules. Compared with melt granulation using DCPD, melt adsorption can be performed over a wide range of 14 to 70% for the ratio of molten components. Moreover, the particle size; d50 of obtained granules was 100-200 µm, and these physical properties showed good flowability and roundness. The process of melt adsorption did not affect the crystalline form of IBU. Therefore, the present study has demonstrated for the first time that melt adsorption using a hydrophobic material, GM or SA, has the potential capability to control the particle size of granules and offers the possibility of application as a novel controlled release technique.
[Mh] Termos MeSH primário: Congelamento
Glicerídeos/química
Tamanho da Partícula
Ácidos Esteáricos/química
Ceras/química
[Mh] Termos MeSH secundário: Adsorção
Compostos de Alumínio/química
Fosfatos de Cálcio/química
Ibuprofeno/química
Compostos de Magnésio/química
Silicatos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aluminum Compounds); 0 (Calcium Phosphates); 0 (Glycerides); 0 (Magnesium Compounds); 0 (Silicates); 0 (Stearic Acids); 0 (Waxes); 230OU9XXE4 (glyceryl monostearate); 4ELV7Z65AP (stearic acid); 6M3P64V0NC (aluminum magnesium silicate); WK2XYI10QM (Ibuprofen)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170804
[St] Status:MEDLINE
[do] DOI:10.1248/cpb.c17-00108


  8 / 3209 MEDLINE  
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[PMID]:28693496
[Au] Autor:Hu J; Guo H; Li J; Wang Y; Xiao L; Xing B
[Ad] Endereço:School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, People's Republic of China.
[Ti] Título:Interaction of γ-Fe O nanoparticles with Citrus maxima leaves and the corresponding physiological effects via foliar application.
[So] Source:J Nanobiotechnology;15(1):51, 2017 Jul 11.
[Is] ISSN:1477-3155
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Nutrient-containing nanomaterials have been developed as fertilizers to foster plant growth and agricultural yield through root applications. However, if applied through leaves, how these nanomaterials, e.g. γ-Fe O nanoparticles (NPs), influence the plant growth and health are largely unknown. This study is aimed to assess the effects of foliar-applied γ-Fe O NPs and their ionic counterparts on plant physiology of Citrus maxima and the associated mechanisms. RESULTS: No significant changes of chlorophyll content and root activity were observed upon the exposure of 20-100 mg/L γ-Fe O NPs and Fe . In C. maxima roots, no oxidative stress occurred under all Fe treatments. In the shoots, 20 and 50 mg/L γ-Fe O NPs did not induce oxidative stress while 100 mg/L γ-Fe O NPs did. Furthermore, there was a positive correlation between the dosages of γ-Fe O NPs and Fe and iron accumulation in shoots. However, the accumulated iron in shoots was not translocated down to roots. We observed down-regulation of ferric-chelate reductase (FRO2) gene expression exposed to γ-Fe O NPs and Fe treatments. The gene expression of a Fe transporter, Nramp3, was down regulated as well under γ-Fe O NPs exposure. Although 100 mg/L γ-Fe O NPs and 20-100 mg/L Fe led to higher wax content, genes associated with wax formation (WIN1) and transport (ABCG12) were downregulated or unchanged compared to the control. CONCLUSIONS: Our results showed that both γ-Fe O NPs and Fe exposure via foliar spray had an inconsequential effect on plant growth, but γ-Fe O NPs can reduce nutrient loss due to their the strong adsorption ability. C. maxima plants exposed to γ-Fe O NPs and Fe were in iron-replete status. Moreover, the biosynthesis and transport of wax is a collaborative and multigene controlled process. This study compared the various effects of γ-Fe O NPs, Fe and Fe chelate and exhibited the advantages of NPs as a foliar fertilizer, laying the foundation for the future applications of nutrient-containing nanomaterials in agriculture and horticulture. Graphical abstract γ-Fe O NPs exposed on plants via foliar spray and genes associated with the absorption and transformation of iron, as well as wax synthesis and secretion in Citrus maxima leaves.
[Mh] Termos MeSH primário: Citrus/efeitos dos fármacos
Citrus/crescimento & desenvolvimento
Compostos Férricos/metabolismo
Fertilizantes
Nanopartículas/metabolismo
Folhas de Planta/efeitos dos fármacos
Folhas de Planta/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Citrus/enzimologia
Citrus/fisiologia
Compostos Férricos/análise
Fertilizantes/análise
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
Peroxidação de Lipídeos/efeitos dos fármacos
Nanopartículas/análise
Folhas de Planta/enzimologia
Folhas de Planta/fisiologia
Ceras/análise
Ceras/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ferric Compounds); 0 (Fertilizers); 0 (Waxes); 1K09F3G675 (ferric oxide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170913
[Lr] Data última revisão:
170913
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170712
[St] Status:MEDLINE
[do] DOI:10.1186/s12951-017-0286-1


  9 / 3209 MEDLINE  
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[PMID]:28658609
[Au] Autor:Vallarino JG; Yeats TH; Maximova E; Rose JK; Fernie AR; Osorio S
[Ad] Endereço:Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora", University of Malaga- Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Department of Molecular Biology and Biochemistry, Campus de Teatinos, 29071, Málaga, Spain.
[Ti] Título:Postharvest changes in LIN5-down-regulated plants suggest a role for sugar deficiency in cuticle metabolism during ripening.
[So] Source:Phytochemistry;142:11-20, 2017 Oct.
[Is] ISSN:1873-3700
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The cell wall invertase gene (LIN5) was reported to be a key enzyme influencing sugar uptake of tomato (Solanum lycopersicum) fruit. It was additionally revealed to be a key regulator of total soluble solids content in fruit as well as for reproductive development, being mainly involved in flower development, early fruit and seed development but also in ripening. Here, we demonstrate that silencing of the LIN5 gene promotes changes affecting fruit cuticle development which has a direct effect on postharvest properties. Transformants were characterized by reduced transpirational water loss in mature fruits accompanied by several other changes in the cuticle. Quantitative chemical composition, coupled with microscopy of isolated cuticle fruits revealed that the cuticle of the transformants were characterized by an increase of the thickness as well as significant increase in the content of cuticle components (cutin, phenolic compounds, and waxes). Furthermore, detailed analysis of the waxes revealed that the transformants displayed changes in waxes composition, showing higher levels of n-alkanes and triterpenoids which can shift the proportion of crystalline and amorphous waxes and change the water flux through the cuticle. Expression of the genes involved in cuticle biosynthesis indicated that LIN5 influences the biosynthesis of components of the cuticle, indicating that this process is coupled to sugar uploading via a mechanism which links carbon supply with the capacity for fruit expansion.
[Mh] Termos MeSH primário: Carboidratos/análise
Epiderme Vegetal/metabolismo
Proteínas de Plantas/metabolismo
beta-Frutofuranosidase/metabolismo
[Mh] Termos MeSH secundário: Parede Celular/metabolismo
Regulação para Baixo
Frutas/enzimologia
Frutas/genética
Frutas/metabolismo
Regulação da Expressão Gênica de Plantas
Lycopersicon esculentum/enzimologia
Lycopersicon esculentum/genética
Lycopersicon esculentum/metabolismo
Lipídeos de Membrana/metabolismo
Fenóis/metabolismo
Ceras/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carbohydrates); 0 (Membrane Lipids); 0 (Phenols); 0 (Plant Proteins); 0 (Waxes); 54990-88-4 (cutin); EC 3.2.1.26 (beta-Fructofuranosidase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170629
[St] Status:MEDLINE


  10 / 3209 MEDLINE  
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[PMID]:28629324
[Au] Autor:Hasanuzzaman M; Davies NW; Shabala L; Zhou M; Brodribb TJ; Shabala S
[Ad] Endereço:School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas, 7001, Australia.
[Ti] Título:Residual transpiration as a component of salinity stress tolerance mechanism: a case study for barley.
[So] Source:BMC Plant Biol;17(1):107, 2017 Jun 19.
[Is] ISSN:1471-2229
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: While most water loss from leaf surfaces occurs via stomata, part of this loss also occurs through the leaf cuticle, even when the stomata are fully closed. This component, termed residual transpiration, dominates during the night and also becomes critical under stress conditions such as drought or salinity. Reducing residual transpiration might therefore be a potentially useful mechanism for improving plant performance when water availability is reduced (e.g. under saline or drought stress conditions). One way of reducing residual transpiration may be via increased accumulation of waxes on the surface of leaf. Residual transpiration and wax constituents may vary with leaf age and position as well as between genotypes. This study used barley genotypes contrasting in salinity stress tolerance to evaluate the contribution of residual transpiration to the overall salt tolerance, and also investigated what role cuticular waxes play in this process. Leaves of three different positions (old, intermediate and young) were used. RESULTS: Our results show that residual transpiration was higher in old leaves than the young flag leaves, correlated negatively with the osmolality, and was positively associated with the osmotic and leaf water potentials. Salt tolerant varieties transpired more water than the sensitive variety under normal growth conditions. Cuticular waxes on barley leaves were dominated by primary alcohols (84.7-86.9%) and also included aldehydes (8.90-10.1%), n-alkanes (1.31-1.77%), benzoate esters (0.44-0.52%), phytol related compounds (0.22-0.53%), fatty acid methyl esters (0.14-0.33%), ß-diketones (0.07-0.23%) and alkylresorcinols (1.65-3.58%). A significant negative correlation was found between residual transpiration and total wax content, and residual transpiration correlated significantly with the amount of primary alcohols. CONCLUSIONS: Both leaf osmolality and the amount of total cuticular wax are involved in controlling cuticular water loss from barley leaves under well irrigated conditions. A significant and negative relationship between the amount of primary alcohols and a residual transpiration implies that some cuticular wax constituents act as a water barrier on plant leaf surface and thus contribute to salinity stress tolerance. It is suggested that residual transpiration could be a fundamental mechanism by which plants optimize water use efficiency under stress conditions.
[Mh] Termos MeSH primário: Hordeum/fisiologia
Transpiração Vegetal
Plantas Tolerantes a Sal/fisiologia
[Mh] Termos MeSH secundário: Hordeum/ultraestrutura
Concentração Osmolar
Epiderme Vegetal/fisiologia
Folhas de Planta/fisiologia
Folhas de Planta/ultraestrutura
Estresse Fisiológico
Água
Ceras
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Waxes); 059QF0KO0R (Water)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170621
[St] Status:MEDLINE
[do] DOI:10.1186/s12870-017-1054-y



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