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1.
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 de Plantas/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
2.
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 Alimentares/análise , Helianthus/química , Proteínas de Plantas/análise , Animais , Aquicultura , Aumento de Peso
3.
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 de Plantas/química , Óleo de Girassol/química , Varredura Diferencial de Calorimetria , Crambe (Planta)/química , Cristalização , Hidrogenação , Conformação Molecular , Ácido Oleico/química , Óleos de Plantas/isolamento & purificação , Temperatura
4.
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 , Glycine max
5.
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
6.
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
7.
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
8.
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
9.
An. acad. bras. ciênc ; 89(3,supl): 2495-2504, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886777

RESUMO

ABSTRACT 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
Animais , Proteínas de Plantas , Crambe (Planta)/química , Peixes , Helianthus/química , Ração Animal , Valor Nutritivo
10.
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 de Plantas/química , Óleos de Plantas/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
11.
J Agric Food Chem ; 62(28): 6707-15, 2014 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-24971658

RESUMO

Ten chemical additives were selected from the literature for their proposed modifying activity in protein-protein interactions. These consisted of acids, bases, reducing agents, and denaturants and were added to residual deoiled meals of Crambe abyssinica (crambe) and Brassica carinata (carinata) to modify the properties of plastics produced through hot compression molding at 130 °C. The films produced were examined for tensile properties, protein solubility, molecular weight distribution, and water absorption. Of the additives tested, NaOH had the greatest positive effect on tensile properties, with increases of 105% in maximum stress and 200% in strain at maximum stress for crambe and a 70% increase in strain at maximum stress for carinata. Stiffness was not increased by any of the applied additives. Changes in tensile strength and elongation for crambe and elongation for carinata were related to changes in protein solubility. Increased pH was the most successful in improving the protein aggregation and mechanical properties within the complex chemistry of residual oilseed meals.


Assuntos
Brassica/química , Crambe (Planta)/química , Óleos de Plantas/química , Proteínas de Plantas/química , Plásticos/química , Ácido Cítrico/farmacologia , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidróxido de Sódio/farmacologia , Solubilidade , Resistência à Tração
12.
Artigo em Inglês | MEDLINE | ID: mdl-21505232

RESUMO

With the development of highly brilliant and extremely intense synchrotron X-ray sources, extreme high-resolution limits for biological samples are now becoming attainable. Here, a study is presented that sets the record in crystallographic resolution for a biological macromolecule. The structure of the small protein crambin was determined to 0.48 Šresolution on the PETRA II ring before its conversion to a dedicated synchrotron-radiation source. The results reveal a wealth of details in electron density and demonstrate the possibilities that are potentially offered by a high-energy source. The question now arises as to what the true limits are in terms of what can be seen at such high resolution. From what can be extrapolated from the results using crystals of crambin, this limit would be at approximately 0.40 Å, which approaches that for smaller compounds.


Assuntos
Crambe (Planta)/química , Proteínas de Plantas/química , Sequência de Aminoácidos , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência
13.
Nat Prod Res ; 22(6): 525-32, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18415861

RESUMO

Native Crambe orientalis var. orientalis and Crambe tataria var. tataria collected from Kahramanmaras flora were morphologically examined and seed oil composition was determined. Volatile acid and fatty acid composition of seeds were examined with GC and GC/MS and the ratio of volatile acids to total oil was 3.49% in C. orientalis and 17.49% in C. tataria. The ratio of fatty acids to total oil was 92.03 and 67.28% in C. orientalis, and C. Tataria, respectively. The amount of erucic acid was 39.29% in C. orientalis and 29.87% in C. tataria. High linolenic acid (21.21%) and linoleic acid (12.42%) was found in C. orientalis oil, and high linolenic acid (15.01%) and linoleic acid (9.00%) was also found in C. tataria oil.


Assuntos
Crambe (Planta)/química , Ácidos Graxos/química , Óleos de Plantas/química , Terpenos/química , Crambe (Planta)/anatomia & histologia , Ácidos Graxos/isolamento & purificação , Espectrometria de Massas , Óleos de Plantas/isolamento & purificação , Sementes/química , Terpenos/isolamento & purificação , Turquia
14.
Protein Sci ; 13(8): 2120-9, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15238635

RESUMO

H-bonding between protein surface polar/charged groups and water is one of the key factors of protein hydration. Here, we introduce an Accessible Surface Area (ASA) model for computationally efficient estimation of a free energy of water-protein H-bonding at any given protein conformation. The free energy of water-protein H-bonds is estimated using empirical formulas describing probabilities of hydrogen bond formation that were derived from molecular dynamics simulations of water molecules at the surface of a small protein, Crambin, from the Abyssinian cabbage (Crambe abyssinica) seed. The results suggest that atomic solvation parameters (ASP) widely used in continuum hydration models might be dependent on ASA for polar/charged atoms under consideration. The predictions of the model are found to be in qualitative agreement with the available experimental data on model compounds. This model combines the computational speed of ASA potential, with the high resolution of more sophisticated solvation methods.


Assuntos
Crambe (Planta)/química , Modelos Químicos , Proteínas de Plantas/química , Sementes/química , Água/química , Ligação de Hidrogênio , Estrutura Molecular , Conformação Proteica , Termodinâmica
15.
J Am Chem Soc ; 126(5): 1377-83, 2004 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-14759195

RESUMO

Crambin is a small (46 amino acids) protein isolated from the seeds of the plant Crambe abyssinica. Crambin has been extensively used as a model protein for the development of advanced crystallography and NMR techniques and for computational folding studies. We set out to establish synthetic access to crambin. Initially, we synthesized the 46 amino acid polypeptide by native chemical ligation of two distinct sets of peptide segments (15 + 31 and 31 + 15 residues). The synthetic polypeptide chain folded in good yield to give native crambin containing three disulfide bonds. The chemically synthesized crambin was characterized by LC-MS and by 2D-NMR. However, the 31-residue peptide segments were difficult to purify, and this caused an overall low yield for the synthesis. To overcome this problem, we synthesized crambin by the native chemical ligation of three segments (15 + 16 + 15 residues). Total synthesis using the ligation of three segments gave more than a 10-fold increase in yield and a protein product of exceptionally high purity. This work demonstrates the efficacy of chemical protein synthesis by the native chemical ligation of three segments and establishes efficient synthetic access to the important model protein crambin for experimental studies of protein folding and stability.


Assuntos
Proteínas de Plantas/síntese química , Sequência de Aminoácidos , Crambe (Planta)/química , Espectrometria de Massas , Modelos Moleculares , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Proteínas de Plantas/química , Isoformas de Proteínas
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