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1.
J Environ Manage ; 262: 110342, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250818

RESUMO

The search for vegetal species regarding effectiveness in the phytoremediation of soils is of great importance, mainly in function of the great environmental problems, such as soil contamination with heavy metals, the necessity of producing more food, among others that mankind face today. This work aimed (i) to evaluate phytoremediation capacity of Crambe abyssinica Hochst and its growth in soil artificially contaminated with Cd and Pb, and (ii) to evaluate the possible impacts of crambe cultivation in contaminated soil conditions, in order to evaluate, to test, and to question the Brazilian CONAMA 420, providing important information that can be useful for governmental and environmental purposes. Two simultaneous experiments were developed, one for each metal. The soils were contaminated with salts of CdCl2 and PbCl2H2O in five doses based on the investigation values (IV) of CONAMA Resolution 420, resulting in 0; 1.5; 3; 9 and 30 mg kg-1 for Cd and 33; 90; 180; 540 and 1800 mg kg-1 for Pb. Gaseous exchange, development, nutritional composition and production of plant components, as well as phytoavailability of metals, were evaluated. The contamination with metals reduced photosynthesis, increased breathing as well as leading to a negative effect on the mineral nutrition and productivity in general; Plants cultivated in soil with Cd presented higher phytoavailability when compared to those cultivated in the Pb conditions, being found metals in all parts of the crambe plants from 1.5 mg kg- 1 of Cd in the soil; and Pb was retained only in roots, not being translocated in the plant. Cd showed higher phytoavailability, being found in all parts of the plant and Pb was retained only in the roots. Cd showed a higher phytoavailability when compared to Pb, also being found in all parts of crambe plants from dose 1.5 mg kg-1 of Cd in soil, which is an environmental problem, since in these concentrations the cultivation of crops is allowed by Brazilian legislation CONAMA 420.


Assuntos
Crambe (Planta) , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Brasil , Cádmio , Chumbo , Solo
2.
Plant Cell Physiol ; 60(6): 1274-1283, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31056666

RESUMO

As an important industrial feedstock, wax esters (WEs) have been used as lubricants in a number of technical processes. There is however currently no large-scale biological source for WE production and alteration in metabolic pathways of plant oils for producing WEs could be attractive to the commercial markets. Here, we present the breeding results of long-term studies on successful development of new crambe lines producing WEs through genetic engineering and cross breeding. The transgenic crambe lines producing WEs at over 25% of the total seed oil were first generated by introduction of the jojoba WE biosynthetic genes ScFAR and ScWS. Further improvement of the lines aiming at improving oxidative stability of WEs was achieved through introducing the CaFAD2-RNAi gene into these lines by crossing. The hybrid lines possessed similar agronomic traits to the wild type and a stable level of WEs over several generations, suggesting a high potential of crambe as an industrial crop for WE production.


Assuntos
Crambe (Planta)/metabolismo , Engenharia Metabólica , Melhoramento Vegetal , Óleos Vegetais/metabolismo , Crambe (Planta)/genética , Genes de Plantas , Engenharia Genética , Óleos Industriais , Engenharia Metabólica/métodos , Melhoramento Vegetal/métodos , Plantas Geneticamente Modificadas , Sementes/metabolismo , Ceras/metabolismo
3.
An Acad Bras Cienc ; 90(4): 3781-3790, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30517222

RESUMO

The objective of this study was to evaluate growth and metabolic parameters of silver catfish fed with protein concentrates of sunflower meal (SMPC) and crambe meal (CrMPC). The study evaluated two levels of substitution, where 25 or 50% of animal protein was replaced with plant-based protein. A total of 300 silver catfish (14 ± 0.26 g) were used in five treatments and three replications, in fifteen 280-liter experimental units. The results were submitted to analysis of variance and the means of the control diet was compared to the remaining treatments by Dunnett's test at 5% significance level. At the end of the trial, no differences were observed for the variables final weight and daily weight gain. However, minor feed conversion was observed in the groups Control and SMPC-25%. Metabolic parameters were analyzed in the plasma and liver, where no significant differences were found for any of the blood parameters analyzed. In the analyzed liver parameters (ammonia, protein, amino acids and ALAT), the liver protein content was lower in fish consuming SMPC-50%, CrMPC-50% and 25% CrMPC diets. The amino acids content was higher in fish receiving the SMPC-25% diet. It can be concluded that sunflower meal protein concentrate is better utilized by fish and more efficient metabolically than crambe meal. This study demonstrated that a newly developed protein concentrate SMPC and CrMPC can effectively replace 25% and 50% the animal protein in a diet free of FM.


Assuntos
Ração Animal/análise , Peixes-Gato/crescimento & desenvolvimento , Crambe (Planta)/química , Proteínas na Dieta/análise , Helianthus/química , Proteínas de Plantas/análise , Animais , Aquicultura , Ganho de Peso
4.
Molecules ; 23(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544618

RESUMO

Raw vegetable oil from Crambe abyssinica was subjected to oxidative treatment to enhance its viscosity. The oxidation processes were carried out in the presence of N-hydroxyphthalimide with or without supercritical CO2 as a solvent. Four spectroscopic techniques (Raman, UV-VIS, FT-IR, NMR) were applied to assess the chemical changes taking place during the oxidation. Raman and NMR spectroscopy proved best in the assessment of the chemical transformations leading to increased viscosity of the modified vegetable oil.


Assuntos
Crambe (Planta)/química , Óleos Vegetais/química , Verduras/química , Ácidos Graxos/análise , Oxirredução , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Triglicerídeos/química
5.
Plant Physiol Biochem ; 129: 310-322, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29925047

RESUMO

Crambe abyssinica is widely cultivated in the off-season in the Midwest region of Brazil with great potential for biodeisel production. Low precipitation is characteristic of this region, which can drastically affect the productivity of C. abyssinica. Signaling molecules, such as nitric oxide (NO), can potentially alleviate the effects of water stress on plants. Here we test whether nitric oxide, applied by donor sodium nitroprusside (SNP), can alleviate the occurrence of water deficit damages in Crambe plants and maintain physiological and biochemical processes. Crambe plants were sprayed with three doses of SNP (0, 75, and 150 µM) and were submitted to two water levels (100% and 50% of the maximum water holding capacity). After 32 and 136 h, leaves were analyzed to evaluate the concentration of NO, water relations, gas exchange, chlorophyll a fluorescence, chloroplastidic pigments, proline, malondialdehyde, hydrogen peroxide, superoxide anions, and the antioxidant enzymes activity. Application of SNP allowed the maintenance of gas exchange, chlorophyll fluorescence parameters, and activities of antioxidant enzymes in plants exposed to water deficit, as well as increased the concentration of NO, proline, chloroplastidic pigments and osmotic potential. The application of SNP also decreased the concentration of malondialdehyde and reactive oxygen species in plants submitted to water deficit. Thus, the application of SNP prevented the occurrence of symptoms of water deficit in Crambe plants, maintaining the physiological and biochemical responses at reference levels, even under stress conditions.


Assuntos
Crambe (Planta)/metabolismo , Óxido Nítrico/metabolismo , Clorofila A/metabolismo , Crambe (Planta)/efeitos dos fármacos , Desidratação , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Nitroprussiato/farmacologia , Pressão Osmótica/efeitos dos fármacos , Transpiração Vegetal/efeitos dos fármacos , Prolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Água/metabolismo
6.
Gene ; 671: 36-49, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-29802993

RESUMO

Crambe abyssinica is an important oilseed crop that accumulates high levels of erucic acid, which is being recognized as a potential oil platform for several industrial purposes. It belongs to the family Brassicaceae, assigned within the tribe Brassiceae. Both family and tribe have been the subject of several phylogenetic studies, but the relationship between some lineages and genera remains unclear. Here, we report the complete sequencing and characterization of the C. abyssinica plastome. Plastome structure, gene order, and gene content of C. abyssinica are similar to other species of the family Brassicaceae. The only exception is the rps16 gene, which is absent in many genera within the family Brassicaceae, but seems to be functional in the tribe Brassiceae, including C. abyssinica. However, the analysis of gene divergence shows that the rps16 is the most divergent gene in C. abyssinica and within the tribe Brassiceae. In addition, species of the tribe Brassiceae also show similar SSR loci distribution, with some regions containing a high number of SSRs, which are located mainly at the single copy regions. Six hotspots of nucleotide divergence among Brassiceae species were located in the single copy regions by sliding window analysis. Brassicaceae phylogenomic analysis, based on the complete plastomes of 72 taxa, resulted in a well-supported and well-resolved tree. The genus Crambe is positioned within the Brassiceae clade together with the genera Brassica, Raphanus, Sinapis, Cakile, Orychophragmus and Sinalliaria. Moreover, we report several losses and gains of RNA editing sites that occurred in plastomes of Brassiceae species during evolution.


Assuntos
Cloroplastos/genética , Crambe (Planta)/genética , Edição de RNA , Análise de Sequência de DNA/métodos , Evolução Molecular , Ordem dos Genes , Tamanho do Genoma , Genoma de Cloroplastos , Repetições de Microssatélites , Filogenia
7.
Food Res Int ; 107: 61-72, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29580526

RESUMO

Several studies have shown that excessive intake of trans and saturated fatty acids is associated with an increased risk of cardiovascular disease. In this context, the food industry has sought alternatives for the development of healthy lipid bases, with higher levels of unsaturated fatty acids, adapting to current legislation. The incorporation of structuring agents into liquid oils has proven to be a potential alternative for obtaining semi-plastic lipid bases with reduced levels of saturated fatty acids. Thus, the objective of this study was to produce zero trans fat bases with lower saturated fatty acids levels. Palm oil (PO) was used as a zero trans-lipid base reference because of its technological functionality. Blends containing different proportions of high oleic sunflower oil (HOSO) and PO were prepared as follows: control 100: 0; 80:20; 60:40; 40:60; 20:80; and 100: 0 PO: HOSO (w/w%), respectively. Then, 3% of fully hydrogenated crambe oil (FHCO) and 3% sorbitan monostearate (SMS) were added to the blends as structuring agents, forming the structured (S) blends. The addition of HOSO to the PO decreased the saturated fatty acids by up to 30.6%, with consequent increase of unsaturated fatty acids, especially oleic acid. The joint action of the SMS and the FCHO allowed for obtaining structured blends with plastic and spreadability characteristics, as well as modifications throughout the crystallization process of the original blends.


Assuntos
Crambe (Planta) , Emulsificantes/química , Manipulação de Alimentos/métodos , Hexoses/química , Óleo de Palmeira/química , Óleos Vegetais/química , Óleo de Girassol/química , Varredura Diferencial de Calorimetria , Crambe (Planta)/química , Cristalização , Hidrogenação , Conformação Molecular , Ácido Oleico/química , Óleos Vegetais/isolamento & purificação , Temperatura
8.
Anim Sci J ; 89(1): 79-87, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28960716

RESUMO

Thermal analysis could rapidly and easily predict nutritional value of ruminant feeds. The hypothesis is that crambe meal (CM) has a quality similar to that of soybean meal (SM), and the objective of this study was to determine the nutritional characteristics of CM and compare them to those of SM. CM had greater concentrations of phytic acid (26.3 vs. 16.0 g/kg) and phenol compounds (615 vs. 393 mg gallic acid (GAE)/kg) than SM. In vitro dry matter (DM) digestibility was lower for CM than SM (752 vs. 975 g/kg DM). Cumulative in vitro gas production at 48 h of incubation (14.1 vs. 19.4 mL/100 mg substrate DM), and energy release (4.5 vs. 5.7 kJ/g substrate DM) were lower for CM than SM. CM had a higher concentration of low digestible fiber, hence degradability of DM was lower and the proportion of indigestible fraction was greater for CM than SM. High concentrations of indigestible compounds were likely responsible for lower gas production of CM compared to SM. These results suggest CM quality is lower than that of SM and that thermal analysis is a useful tool to precisely determine the nutritive value of oilseed residues.


Assuntos
Ração Animal/análise , Biocombustíveis , Calorimetria/métodos , Crambe (Planta)/química , Digestão , Valor Nutritivo , Ácido Gálico/análise , Gases/análise , Técnicas In Vitro , Fenóis/análise , Ácido Fítico/análise , Soja
9.
Trop Anim Health Prod ; 50(1): 143-148, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28942546

RESUMO

We studied the feed intake and milk production of Holstein × Zebu crossbred cows fed sorghum silage diets and concentrates, with and without the addition of crambe meal. Using a change-over design for a total of 120 days, eight cows were fed two diets (concentrates + silages with and without crambe meal) in four 30-day periods, with four replications (animals). The crambe meal diet increased (P < 0.05) the dry matter intake (DMI), crude protein intake (CPI), and non-fibrous carbohydrates intake (NFCI) as well as milk production (4.3%). No difference was noted (P > 0.05) for the milk composition between the treatments. Crambe meal as an additive in sorghum silage (100 g/kg in natural matter) showed a great potential for introduction in dairy farming as it substantially increases CP intake, does not reduce food intake, raises animal productivity, and does not affect milk composition.


Assuntos
Bovinos/fisiologia , Crambe (Planta)/química , Dieta/veterinária , Comportamento Alimentar , Leite/metabolismo , Sorghum/química , Animais , Bovinos/genética , Suplementos Nutricionais/análise , Feminino , Lactação , Silagem/análise
10.
Food Res Int ; 99(Pt 1): 713-719, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28784535

RESUMO

The objective of this work was to produce structured lipids (SLs) from olive oil (O), soybean oil (S), and fully hydrogenated crambe oil - FHCO (C) mixtures by enzymatic interesterification, comparing Lipozyme TL IM and Rhizopus sp. performances as catalysts, and to evaluate their physical and chemical modifications. Among other blends (OC 90:10 w/w and SC 90:10 w/w), OSC (45:45:10, w/w), presented the most nutritionally interesting amounts of mono- and polyunsaturated fatty acids, as well as behenic acid. Interesterification caused an increase in crystallization time and a decrease in the solid fat content in all blends. The fatty acid redistribution in the TAGs caused a change in thermal behavior, leading to a decrease in the onset and end temperatures during crystallization, which indicates that new TAGs were formed. Regarding regiospecificity, Lipozyme TL IM lipase acted randomly, while Rhizopus sp. lipase was specific for the sn-1,3 position. Therefore, it was possible to synthesize SLs presenting different physical and chemical properties, compared to the original OSC blend, containing behenic acid at the sn-1,3 position and unsaturated fatty acids at the sn-2 position, by enzymatic interesterification catalyzed either by Lipozyme TL IM or by Rhizopus sp. lipases.


Assuntos
Fármacos Antiobesidade/análise , Ácidos Graxos Essenciais/análise , Lipídeos/análise , Azeite de Oliva/análise , Óleo de Brassica napus/análise , Óleo de Soja/análise , Fármacos Antiobesidade/química , Crambe (Planta)/química , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos Essenciais/química , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/química , Lipídeos/química , Azeite de Oliva/química , Óleo de Brassica napus/química , Óleo de Soja/química
11.
An Acad Bras Cienc ; 89(3 Suppl): 2495-2504, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28746613

RESUMO

The purpose of this study was to develop and improve protein concentration techniques for two industrial by-products with the potential for use in fish feed. In particular, we chemically characterized crambe meal and sunflower meal and their protein concentrates. Three different protein concentration methods were tested: isoelectric pH (pHi), acid pH and alkaline pH. For crambe and sunflower meals extraction using the pHi method was most efficient in terms of protein yield and crude protein content in the concentrates; this method also increased lysine and methionine content in the concentrates. The water holding capacity of the sunflower protein concentrate was greater than that of the crambe protein concentrate. The crambe protein concentrate had a foam-formation capacity of 15%, which stabilized at 6% after 90 minutes. The protein concentration method also reduced total phenolic content by approximately 50% in the concentrates compared with the meals. Therefore, we conclude that protein concentration using the pHi method is the most efficient technique for crambe and sunflower meals, and the use of this technique can decrease total phenolic compounds while improving meal quality for fish feeding.


Assuntos
Ração Animal , Crambe (Planta)/química , Peixes , Helianthus/química , Valor Nutritivo , Proteínas de Plantas/análise , Animais
12.
J Vis Exp ; (119)2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28117827

RESUMO

Crambe abyssinica is a plant with potential for use in industrial (non-food) plant oil production. The side stream from this oil production is a high-protein crambe meal that has limited value, as it is not fit for food or feed use. However, it contains proteins that could potentially make it a suitable raw material for higher-value products. The purpose of this study was to find methods of making this side stream into extruded films, showing that products with a higher value can be produced. The study mainly considered the development of material compositions and methods of preparing and extruding the material. Wheat gluten was added as a supportive protein matrix material, together with glycerol as a plasticizer and urea as a denaturant. The extrudate was evaluated with respect to mechanical (tensile testing) and oxygen barrier properties, and the extrudate structure was revealed visually and by scanning electron microscopy. A denser, more homogeneous material had a lower oxygen transmission rate, higher strength, and higher extensibility. The most homogeneous films were made at an extruder die temperature of 125-130 °C. It is shown here that a film can be extruded with promising mechanical and oxygen barrier properties, the latter especially after a final compression molding step.


Assuntos
Crambe (Planta)/química , Glutens/química , Triticum/química , Glicerol/química , Plastificantes/química , Temperatura , Resistência à Tração , Ureia/química
13.
Biotechnol Bioeng ; 114(6): 1275-1282, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27943249

RESUMO

Biotechnological production of fatty alcohols, important raw materials in the chemical industry, has been receiving considerable attention in recent years. Fatty alcohols are formed by the reduction of fatty acyl-CoAs or fatty acyl-ACPs catalyzed by a fatty acyl reductase (FAR). In this study, we introduced genes encoding FARs from Arabidopsis thaliana (AtFAR5) and Simmondsia chinensis (ScFAR) into Crambe abyssinica hairy roots via Agrobacterium rhizogenes-mediated transformation. The efficiency of the transformation ranged between 30 and 45%. The fatty alcohols were only detected in the transgenic hairy root lines expressing ScFAR gene. In all tested lines stearyl alcohol (18:0-OH), arachidyl alcohol (20:0-OH), and behenyl alcohol (22:0-OH) were produced. The content of 18:0-OH varied from 1 to 3% of total fatty acids and fatty alcohols, while the amount of either 20:0-OH and 22:0-OH did not exceed 2%. The transgenic hairy root lines produced from 0.98 to 2.59 nmol of fatty alcohols per mg of dry weight. Very low activity of ScFAR was detected in the microsomal fractions isolated from the selected hairy root lines. To our knowledge, this is the first report on the fatty alcohol production in the hairy root cultures. Biotechnol. Bioeng. 2017;114: 1275-1282. © 2016 Wiley Periodicals, Inc.


Assuntos
Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Crambe (Planta)/fisiologia , Álcoois Graxos/metabolismo , Engenharia Metabólica/métodos , Raízes de Plantas/fisiologia , Álcoois Graxos/isolamento & purificação , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
14.
BMC Plant Biol ; 16(1): 139, 2016 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-27317011

RESUMO

BACKGROUND: The allohexaploid Crambe abyssinica (crambe) is an oilseed crop that has been recognized for its potential value in the chemical industry, particularly in terms of producing high-erucic acid content vegetable oil. However, as an understudied crop, improvement of crambe has been hampered by the lack of genetic and genomic information to enhance its yield, oil quality and resistance against biotic and abiotic stress. Development of molecular markers is therefore of great significance to facilitate genetic improvement of crambe. RESULTS: In this study, high-throughput sequencing was performed to generate sequences for the transcriptome and genome of a widely planted crambe cultivar, Galactica. A total of 186,778 expressed sequence tag (EST) contigs as 8,130,350 genomic contigs were assembled as well. Altogether, 82,523 pairs of primers were designed in the flanking sequences of the simple sequence repeat (SSR) within these contigs. Virtual PCR analysis showed that a fraction of these primers could be mapped onto the genomes of related species of Brassica, including Brassica rapa, B. oleraceae and B. napus. Genetic diversity analysis using a subset of 166 markers on 30 independent C. abyssinica accessions exhibited that 1) 95 % of the designed SSRs were polymorphic among these accessions; 2) the polymorphism information content (PIC) value of the markers ranged from 0.13 to 0.89; 3) the genetic distances (coefficient NEI72) between accessions varied from 0.06 to 0.36. Cluster analysis subsequent on the accessions demonstrated consistency with crambe breeding history. F-statistics analysis revealed a moderate level of genetic differentiation in C. abyssinica (Gst = 0.3934) and a accordingly low estimated gene flow (Nm = 0.7709). CONCLUSION: Application of high-throughput sequencing technology has facilitated SSR marker development, which was successfully employed in evaluating genetic diversity of C. abyssinica as demonstrated in our study. Results showed these molecular markers were robust and provided powerful tools for assessing genetic diversity and estimating crambe breeding history. Moreover, the SSR primers and sequence information developed in the study are freely available to the research community.


Assuntos
Crambe (Planta)/genética , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Repetições de Microssatélites , Brassica/genética , Crambe (Planta)/classificação , Etiquetas de Sequências Expressas , Marcadores Genéticos , Polimorfismo Genético
15.
Plant Biotechnol J ; 14(1): 323-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25998013

RESUMO

High oleic oil is an important industrial feedstock that has been one of the main targets for oil improvement in a number of oil crops. Crambe (Crambe abyssinica) is a dedicated oilseed crop, suitable for industrial oil production. In this study, we down-regulated the crambe fatty acid desaturase (FAD) and fatty acid elongase (FAE) genes for creating high oleic seed oil. We first cloned the crambe CaFAD2, CaFAD3 and CaFAE1 genes. Multiple copies of each of these genes were isolated, and the highly homologous sequences were used to make RNAi constructs. These constructs were first tested in Arabidopsis, which led to the elevated oleic or linoleic levels depending on the genes targeted, indicating that the RNAi constructs were effective in regulating the expression of the target genes in nonidentical but closely related species. Furthermore, down-regulation of CaFAD2 and CaFAE1 in crambe with the FAD2-FAE1 RNAi vector resulted in even more significant increase in oleic acid level in the seed oil with up to 80% compared to 13% for wild type. The high oleic trait has been stable in subsequent five generations and the GM line grew normally in greenhouse. This work has demonstrated the great potential of producing high oleic oil in crambe, thus contributing to its development into an oil crop platform for industrial oil production.


Assuntos
Acetiltransferases/metabolismo , Arabidopsis/genética , Crambe (Planta)/enzimologia , Regulação para Baixo , Ácidos Graxos Dessaturases/metabolismo , Ácido Oleico/metabolismo , Óleos Vegetais/metabolismo , Sementes/metabolismo , Southern Blotting , Segregação de Cromossomos/genética , Elongases de Ácidos Graxos , Dosagem de Genes , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Genes de Plantas , Família Multigênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Especificidade da Espécie
16.
Genet Mol Res ; 14(4): 16450-60, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26662443

RESUMO

Crambe (Crambe abyssinica) is a non-edible annual herb, which was first cultivated to extract oil for industry, and now has great potential for biodiesel production. The objective of this investigation was to evaluate the genetic stability of micropropagated plants of the C. abyssinica Hochst cultivar 'FMS brilhante' using polymerase chain reaction techniques based on inter-simple sequence repeat (ISSR) molecular markers. The aim was to develop a protocol for the in vitro regeneration of these plants with low genetic variation as compared to the donor plant. For micropropagation, shoot tips from in vitro germinated seedlings were used as explants and were initially cultivated for 90 days on MS medium with 5.0 µM 6-benzylaminopurine (BAP), which at 90 days, led to the highest number of shoots per explant (NSE) (12.20 shoots) being detected. After 120 days, the interaction between BAP concentration and naphthalene acetic acid (NAA) was tested, and the highest NSE was observed following exposure to 0.0/0.5 µM BAP/NAA (11.40 shoots) and 1.0/0.0 µM BAP/NAA (11.00 shoots). The highest proportion of rooting phase were observed following exposure to 0.5 µM NAA (30%). The 13 ISSR primers used to analyze genetic stability produced 91 amplification products, of which only eight bands were polymorphic and 83 were monomorphic for all 10 regenerated crambe plants, compared to the donor plant explant. These results indicate that crambe shoot tips are a highly reliable explant that can be used to micropropagate genetically true-to-type plants or to maintain genetic stability, as verified using ISSR markers.


Assuntos
Crambe (Planta)/crescimento & desenvolvimento , Crambe (Planta)/genética , Instabilidade Genômica , Repetições de Microssatélites , Crambe (Planta)/efeitos dos fármacos , DNA de Plantas , Reguladores de Crescimento de Planta/farmacologia , Brotos de Planta
17.
Environ Sci Technol ; 49(16): 10117-26, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26186015

RESUMO

Silver nanoparticles (Ag NPs) are widely used in consumer products, and their release has raised serious concerns about the risk of their exposure to the environment and to human health. However, biochemical mechanisms by which plants counteract NP toxicity are largely unknown. We have previously engineered Crambe abyssinica plants expressing the bacterial γ-glutamylecysteine synthase (γ-ECS) for enhancing glutathione (GSH) levels. In this study, we investigated if enhanced levels of GSH and its derivatives can protect plants from Ag NPs and AgNO3 (Ag(+) ions). Our results showed that transgenic lines, when exposed to Ag NPs and Ag(+) ions, were significantly more tolerant, attaining a 28%-46% higher biomass and 34-49% more chlorophyll content, as well as maintaining 35-46% higher transpiration rates as compared to those of wild type (WT) plants. Transgenic γ-ECS lines showed 2-6-fold Ag accumulation in shoot tissue and slightly lower or no difference in root tissue relative to levels in WT plants. The levels of malondialdehyde (MDA) in γ-ECS lines were also 27.3-32.5% lower than those in WT Crambe. These results indicate that GSH and related peptides protect plants from Ag nanotoxicity. To our knowledge, this is the first direct report of Ag NP detoxification by GSH in transgenic plants, and these results will be highly useful in developing strategies to counteract the phytotoxicty of metal-based nanoparticles in crop plants.


Assuntos
Crambe (Planta)/efeitos dos fármacos , Dipeptídeos/metabolismo , Escherichia coli/enzimologia , Glutationa/metabolismo , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Biomassa , Clorofila/metabolismo , Crambe (Planta)/crescimento & desenvolvimento , Cisteína/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fitoquelatinas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Transpiração Vegetal/efeitos dos fármacos , Plantas Geneticamente Modificadas
18.
Lipids ; 50(4): 407-16, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25753896

RESUMO

The aim of this study was to evaluate the importance of three enzymes, LPCAT, PDCT and PDAT, involved in acyl turnover in phosphatidylcholine in order to explore the possibility of further increasing erucic acid (22:1) content in Crambe seed oil. The complete coding sequences of LPCAT1-1 and LPCAT1-2 encoding lysophosphatidylcholine acyltransferase (LPCAT), PDCT1 and PDCT2 encoding phosphatidylcholine:diacylglycerol cholinephosphotransferase (PDCT), and PDAT encoding phospholipid:diacylglycerol acyltransferase (PDAT) were cloned from developing Crambe seeds. The alignment of deduced amino acid sequences displayed a high similarity to the Arabidopsis homologs. Transgenic lines expressing RNA interference (RNAi) targeting either single or double genes showed significant changes in the fatty acid composition of seed oil. An increase in oleic acid (18:1) was observed, to varying degrees, in all of the transgenic lines, and a cumulative effect of increased 18:1 was shown in the LPCAT-PDCT double-gene RNAi. However, LPCAT single-gene RNAi led to a decrease in 22:1 accumulation, while PDCT or PDAT single-gene RNAi had no obvious effect on the level of 22:1. In agreement with the abovementioned oil phenotypes, the transcript levels of the target genes in these transgenic lines were generally reduced compared to wild-type levels. In this paper, we discuss the potential to further increase the 22:1 content in Crambe seed oil through downregulation of these genes in combination with fatty acid elongase and desaturases.


Assuntos
Crambe (Planta)/enzimologia , Crambe (Planta)/genética , Ácidos Erúcicos/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Interferência de RNA , 1-Acilglicerofosfocolina O-Aciltransferase/química , 1-Acilglicerofosfocolina O-Aciltransferase/genética , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Aciltransferases/química , Aciltransferases/genética , Aciltransferases/metabolismo , Sequência de Aminoácidos , Crambe (Planta)/química , Crambe (Planta)/metabolismo , Ácidos Erúcicos/análise , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Óleos Vegetais/química , Óleos Vegetais/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/metabolismo , Sementes/química , Sementes/enzimologia , Sementes/genética , Sementes/metabolismo , Alinhamento de Sequência , Transferases (Outros Grupos de Fosfato Substituídos)/química , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
19.
An Acad Bras Cienc ; 87(1): 137-45, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25806981

RESUMO

Despite the economic importance of Crambe abyssinica, the present study is the first report on bees that occur with this species, and could aid in developing alternative methods for controlling insect pests without seriously impacting pollinators. The present study examined the following questions: (1) Which species are potential pollinators of C. abyssinica? (2) How do environmental conditions influence pollinator visitation fluctuations? Insects were sampled on a weekly basis between 08:00 and 16:00 during five weeks of flowering. When the results of analyses of variance were significant, the data was adjusted using regression equations at a 5% level of probability; the environmental variables were examined using Pearson's correlation coefficient. Apis mellifera, Geotrigona mombuca, Exomalopsis (Exomalopsis) fulvofasciata, Plebeia sp. and Dialictus sp. were observed visiting C. abyssinica flowers. A. mellifera and G. mombuca were observed to be potential pollinators, with the former demonstrating visitation peaks during flowering weeks II and IV at 12:00 and 08:00, respectively and the latter visiting during weeks III and IV at 12:00 and 10:00, respectively. Environmental factors such as temperature, relative humidity, and wind speed have different effect on the activity of bees.


Assuntos
Abelhas/fisiologia , Crambe (Planta)/fisiologia , Polinização/fisiologia , Animais , Abelhas/classificação , Crambe (Planta)/crescimento & desenvolvimento , Meio Ambiente
20.
Plant Biotechnol J ; 13(4): 471-81, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25393152

RESUMO

Crambe abyssinica is a hexaploid oil crop for industrial applications. An increase of erucic acid (C22:1) and reduction of polyunsaturated fatty acid (PUFA) contents in crambe oil is a valuable improvement. An increase in oleic acid (C18:1), a reduction in PUFA and possibly an increase in C22:1 can be obtained by down-regulating the expression of fatty acid desaturase2 genes (CaFAD2), which code for the enzyme that converts C18:1 into C18:2. We conducted EMS-mutagenesis in crambe, followed by Illumina sequencing, to screen mutations in three expressed CaFAD2 genes. Two novel analysis strategies were used to detect mutation sites. In the first strategy, mutation detection targeted specific sequence motifs. In the second strategy, every nucleotide position in a CaFAD2 fragment was tested for the presence of mutations. Seventeen novel mutations were detected in 1100 one-dimensional pools (11 000 individuals) in three expressed CaFAD2 genes, including non-sense mutations and mis-sense mutations in CaFAD2-C1, -C2 and -C3. The homozygous non-sense mutants for CaFAD2-C3 resulted in a 25% higher content of C18:1 and 25% lower content of PUFA compared to the wild type. The mis-sense mutations only led to small changes in oil composition. Concluding, targeted mutation detection using NGS in a polyploid was successfully applied and it was found that a non-sense mutation in even a single CaFAD2 gene can lead to changes in crambe oil composition. Stacking the mutations in different CaFAD2 may gain additional changes in C18:1 and PUFA contents.


Assuntos
Crambe (Planta)/genética , Ácidos Graxos Dessaturases/genética , Genes de Plantas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação , Óleos Vegetais/metabolismo , Crambe (Planta)/metabolismo
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