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1.
Molecules ; 27(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36557964

RESUMO

In the past two decades, there have been remarkable changes in the way we analyze the physical, chemical, and sensory properties of fresh and processed food products, with the progressive replacement of traditional wet analytical methods (destructive, laborious, time-consuming, and requiring the use of hazardous chemicals) with new, fast, non-destructive physical methods where the analysis is performed in a single step, after validation, and without the use of chemical reagents [...].


Assuntos
Análise de Alimentos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Imageamento por Ressonância Magnética/métodos
2.
Molecules ; 27(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36144797

RESUMO

The food quality of edible oils is dependent on basic chemical and structural changes that can occur by oxidation during preparation and storage. A rapid and efficient analytical method of the different steps of oil oxidation is described using a time-domain nuclear magnetic resonance (TD-NMR) sensor for measuring signals related to the chemical and physical properties of the oil. The degree of thermal oxidation of edible oils at 80 °C was measured by the conventional methodologies of peroxide and aldehyde analysis. Intact non-modified samples of the same oils were more rapidly analyzed for oxidation using a TD-NMR sensor for 2D T1-T2 and self-diffusion (D) measurements. A good linear correlation between the D values and the conventional chemical analysis was achieved, with the highest correlation of R2 = 0.8536 for the D vs. the aldehyde concentrations during the thermal oxidation of poly-unsaturated linseed oils, the oil most susceptible to oxidation. A good correlation between the D and aldehyde levels was also achieved for all the other oils. The possibility to simplify and minimize the time of oxidative analysis using the TD NMR sensors D values is discussed as an indicator of the oil's oxidation quality, as a rapid and accurate methodology for the oil industry.


Assuntos
Qualidade dos Alimentos , Óleos de Plantas , Aldeídos/análise , Espectroscopia de Ressonância Magnética/métodos , Peróxidos/análise , Óleos de Plantas/química
3.
Biosensors (Basel) ; 12(4)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35448290

RESUMO

Food safety monitoring is highly important due to the generation of unhealthy components within many food products during harvesting, processing, storage, transportation and cooking. Current technologies for food safety analysis often require sample extraction and the modification of the complex chemical and morphological structures of foods, and are either time consuming, have insufficient component resolution or require costly and complex instrumentation. In addition to the detection of unhealthy chemical toxins and microbes, food safety needs further developments in (a) monitoring the optimal nutritional compositions in many different food categories and (b) minimizing the potential chemical changes of food components into unhealthy products at different stages from food production until digestion. Here, we review an efficient methodology for overcoming the present analytical limitations of monitoring a food's composition, with an emphasis on oxidized food components, such as polyunsaturated fatty acids, in complex structures, including food emulsions, using compact instruments for simple real-time analysis. An intelligent low-field proton NMR as a time domain (TD) NMR relaxation sensor technology for the monitoring of T2 (spin-spin) and T1 (spin-lattice) energy relaxation times is reviewed to support decision-making by producers, retailers and consumers in regard to food safety and nutritional value during production, shipping, storage and consumption.


Assuntos
Estresse Oxidativo , Prótons , Lipídeos , Espectroscopia de Ressonância Magnética/métodos , Oxirredução
4.
Foods ; 10(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203981

RESUMO

The nutritional characteristics of fatty acid (FA) containing foods are strongly dependent on the FA's chemical/morphological arrangements. Paradoxically the nutritional, health enhancing FA polyunsaturated fatty acids (PUFAs) are highly susceptible to oxidation into harmful toxic side products during food preparation and storage. Current analytical technologies are not effective in the facile characterization of both the morphological and chemical structures of PUFA domains within materials for monitoring the parameters affecting their oxidation and antioxidant efficacy. The present paper is a review of our work on the development and application of a proton low field NMR relaxation sensor (1H LF NMR) and signal to time domain (TD) spectra reconstruction for chemical and morphological characterization of PUFA-rich oils and their oil in water emulsions, for assessing their degree and susceptibility to oxidation and the efficacy of antioxidants. The NMR signals are energy relaxation signals generated by spin-lattice interactions (T1) and spin-spin interactions (T2). These signals are reconstructed into 1D (T1 or T2) and 2D graphics (T1 vs. T2) by an optimal primal-dual interior method using a convex objectives (PDCO) solver. This is a direct measurement on non-modified samples where the individual graph peaks correlate to structural domains within the bulk oil or its emulsions. The emulsions of this review include relatively complex PUFA-rich oleosome-oil bodies based on the aqueous extraction from linseed seeds with and without encapsulation of externally added oils such as fish oil. Potential applications are shown in identifying optimal health enhancing PUFA-rich food formulations with maximal stability against oxidation and the potential for on-line quality control during preparation and storage.

5.
J Magn Reson ; 323: 106899, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33518175

RESUMO

In this contribution, a selective overview of low field, time-domain NMR (TD-NMR) applications in the agriculture and agrifood sectors is presented. The first applications of commercial TD-NMR instruments were in food and agriculture domains. Many of these earlier methods have now been recognized as standard methods by several international agencies. Since 2000, several new applications have been developed, using state of the art instruments, new pulse sequences and new signal processing methods. TD-NMR is expected, in the coming years, to become even more important in quality control of fresh food and agricultural products, as well as for a wide range of food-processed products. TD-NMR systems provide excellent means to collect data relevant for use in the agricultural environment and the bioenergy industry. Data and information collected by TD-NMR systems thus may support decision makers in business and public organizations.


Assuntos
Agricultura , Biocombustíveis , Alimentos , Espectroscopia de Ressonância Magnética/métodos , Plantas
6.
Biotechnol Biofuels ; 8: 96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26167203

RESUMO

BACKGROUND: To identify and develop the best renewable and low carbon footprint biodiesel substitutes for petroleum diesel, the properties of different biodiesel candidates should be studied and characterized with respect to molecular structures versus biodiesel liquid property relationships. In our previous paper, (1)H low-field nuclear magnetic resonance (LF-NMR) relaxometry was investigated as a tool for studying the liquid-phase molecular packing interactions and morphology of fatty acid methyl esters (FAMEs). The technological potential was demonstrated with oleic acid and methyl oleate standards having similar alkyl chains but different head groups. In the present work, molecular organization versus segmental and translational movements of FAMEs in their pure liquid phase, with different alkyl chain lengths (10-20 carbons) and degrees of unsaturation (0-3 double bonds), were studied with (1)H LF-NMR relaxometry and X-ray, (1)H LF-NMR diffusiometry, and (13)C high-field NMR. RESULTS: Based on density values and X-ray measurements, it was proposed that FAMEs possess a liquid crystal-like order above their melting point, consisting of random liquid crystal aggregates with void spaces between them, whose morphological properties depend on chain length and degree of unsaturation. FAMEs were also found to exhibit different degrees of rotational and translational motions, which were rationalized by chain organization within the clusters, and the degree and type of molecular interactions and temperature effects. At equivalent fixed temperature differences from melting point, saturated FAME molecules were found to have similar translational motion regardless of chain length, expressed by viscosity, self-diffusion coefficients, and spin-spin (T 2) (1)H LF-NMR. T 2 distributions suggest increased alkyl chain rigidity, and reduced temperature response of the peaks' relative contribution with increasing unsaturation is a direct result of the alkyl chain's morphological packing and molecular interactions. CONCLUSIONS: Both the peaks' assignments for T 2 distributions of FAMEs and the model for their liquid crystal-like morphology in the liquid phase were confirmed. The study of morphological structures within liquids and their response to temperature changes by (1)H LF-NMR has a high value in the field of biodiesel and other research and applied disciplines in numerous physicochemical- and organizational-based properties, processes, and mechanisms of alkyl chains, molecular interactions, and morphologies.

7.
Biotechnol Biofuels ; 8: 12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25688289

RESUMO

BACKGROUND: (1)H low field nuclear magnetic resonance (LF-NMR) relaxometry has been suggested as a tool to distinguish between different molecular ensembles in complex systems with differential segmental or whole molecular motion and/or different morphologies. In biodiesel applications the molecular structure versus liquid-phase packing morphologies of fatty acid methyl esters (FAMEs) influences physico-chemical characteristics of the fuel, including flow properties, operability during cold weather, blending, and more. Still, their liquid morphological structures have scarcely been studied. It was therefore the objective of this work to explore the potential of this technology for characterizing the molecular organization of FAMEs in the liquid phase. This was accomplished by using a combination of supporting advanced technologies. RESULTS: We show that pure oleic acid (OA) and methyl oleate (MO) standards exhibited both similarities and differences in the (1)H LF-NMR relaxation times (T2s) and peak areas, for a range of temperatures. Based on X-ray measurements, both molecules were found to possess a liquid crystal-like order, although a larger fluidity was found for MO, because as the temperature is increased, MO molecules separate both longitudinally and transversely from one another. In addition, both molecules exhibited a preferred direction of diffusion based on the apparent hydrodynamic radius. The close molecular packing arrangement and interactions were found to affect the translational and segmental motions of the molecules, as a result of dimerization of the head group in OA as opposed to weaker polar interactions in MO. CONCLUSIONS: A comprehensive model for the liquid crystal-like arrangement of FAMEs in the liquid phase is suggested. The differences in translational and segmental motions of the molecules were rationalized by the differences in the (1)H LF-NMR T2 distributions of OA and MO, which was further supported by (13)C high field (HF)-NMR spectra and (1)H HF-NMR relaxation. The proposed assignment allows for material characterization based on parameters that contribute to properties in applications such as biodiesel fuels.

8.
Artigo em Inglês | MEDLINE | ID: mdl-23847452

RESUMO

Low-resolution nuclear magnetic resonance (LR-NMR) relaxometry is a powerful tool that can be harnessed for characterizing constituents in complex materials. Conversion of the relaxation signal into a continuous distribution of relaxation components is an ill-posed inverse Laplace transform problem. The most common numerical method implemented today for dealing with this kind of problem is based on L2-norm regularization. However, sparse representation methods via L1 regularization and convex optimization are a relatively new approach for effective analysis and processing of digital images and signals. In this article, a numerical optimization method for analyzing LR-NMR data by including non-negativity constraints and L1 regularization and by applying a convex optimization solver PDCO, a primal-dual interior method for convex objectives, that allows general linear constraints to be treated as linear operators is presented. The integrated approach includes validation of analyses by simulations, testing repeatability of experiments, and validation of the model and its statistical assumptions. The proposed method provides better resolved and more accurate solutions when compared with those suggested by existing tools. © 2013 Wiley Periodicals, Inc. Concepts Magn Reson Part A 42A: 72-88, 2013.

9.
Biotechnol Biofuels ; 6(1): 55, 2013 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-23590829

RESUMO

BACKGROUND: Biodiesel production has increased dramatically over the last decade, raising the need for new rapid and non-destructive analytical tools and technologies. 1H Low Field Nuclear Magnetic Resonance (LF-NMR) applications, which offer great potential to the field of biodiesel, have been developed by the Phyto Lipid Biotechnology Lab research team in the last few years. RESULTS: Supervised and un-supervised chemometric tools are suggested for screening new alternative biodiesel feedstocks according to oil content and viscosity. The tools allowed assignment into viscosity groups of biodiesel-petrodiesel samples whose viscosity is unknown, and uncovered biodiesel samples that have residues of unreacted acylglycerol and/or methanol, and poorly separated and cleaned glycerol and water. In the case of composite materials, relaxation time distribution, and cross-correlation methods were successfully applied to differentiate components. Continuous distributed methods were also applied to calculate the yield of the transesterification reaction, and thus monitor the progress of the common and in-situ transesterification reactions, offering a tool for optimization of reaction parameters. CONCLUSIONS: Comprehensive applied tools are detailed for the characterization of new alternative biodiesel resources in their whole conformation, monitoring of the biodiesel transesterification reaction, and quality evaluation of the final product, using a non-invasive and non-destructive technology that is new to the biodiesel research area. A new integrated computational-experimental approach for analysis of 1H LF-NMR relaxometry data is also presented, suggesting improved solution stability and peak resolution.

10.
Waste Manag ; 30(10): 1881-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20347586

RESUMO

Production of biodiesel is currently limited due to lack of economically beneficial feedstocks. Suitability of municipal wastewater sludge and olive mill waste as feedstocks for biodiesel production was evaluated. The various bio-waste sources were analyzed for their oil content and fatty acid composition using conventional analyses complemented with time domain (TD)-NMR analysis. TD-NMR, a rapid non-destructive method newly applied in this field, yielded good correlations with conventional methods. Overall biodiesel yields obtained by TD-NMR analysis were 7.05% and 9.18% (dry wt) for olive mill pomace and liquid wastes, and 11.92%, 7.07%, and 4.65% (dry wt) for primary, secondary, and anaerobically stabilized sludge, respectively. Fatty acid analysis indicated fundamental suitability of these agro-industrial waste resources for biodiesel production. Evaluation of bio-waste materials by TD-NMR revealed the potential of this tool to identify waste-oil sources cost effectively and quickly, supporting expansion of a sustainable biodiesel industry in Israel and other regions.


Assuntos
Biocombustíveis , Reatores Biológicos , Espectroscopia de Ressonância Magnética/métodos , Óleos de Plantas , Eliminação de Resíduos/métodos , Esgotos , Ácidos Graxos/análise , Israel , Azeite de Oliva
11.
J Agric Food Chem ; 57(19): 9197-209, 2009 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-19725542

RESUMO

The well-established health beneficial value of pomegranate juice is leading to increased demand for pomegranate products and to the expansion of pomegranate orchards worldwide. The current study describes differences in the chemical composition of major ingredients of the arils and peels of 11 accessions grown in Mediterranean and desert climates in Israel. In most of the accessions, the levels of antioxidant activity and content of total phenolics, total anthocyanins, total soluble solids, glucose, fructose, and acidity were higher in the aril juice of fruit grown in the Mediterranean climate compared to those grown in the desert climate. However, the peels of fruit grown in the desert climate exhibited higher antioxidant activity, and the levels of total phenolics, including the two hydrolyzable tannins, punicalagin and punicalin, were higher compared to those in the peels of fruit grown in the Mediterranean climate. The results indicate that environmental conditions significantly affect pomegranate fruit quality and health beneficial compounds.


Assuntos
Antioxidantes/análise , Cor , Meio Ambiente , Frutas/química , Lythraceae/química , Paladar , Antocianinas/análise , Clima Desértico , Frutose/análise , Glucose/análise , Israel , Região do Mediterrâneo , Fenóis/análise , Óleos de Plantas/análise , Sementes/química , Taninos
12.
Methods Mol Biol ; 579: 315-36, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19763483

RESUMO

Vegetable oils are complex mixtures containing a wide range of major compounds. Triacylglycerols (TAGs; consisting of a glycerol moiety with each hydroxyl group esterified to a fatty acid) are the major components (95-98%) of vegetable oils. TAGs are an important source of energy and nutrition for humans, so their compositional analysis merits extensive interest. Analysis of TAGs has increased in recent years and the advancement has been driven by the development of analytical technologies. This chapter discusses techniques for determination of TAG and fatty acid profiles (FAPs) of vegetable oils using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF/MS) and gas chromatography-mass spectrometry (GC/MS). Considering the importance of TAG in its native form, rather than FAPs, special emphasis has been given to the TAG fingerprinting analyses of intact oils. MALDI-TOF/MS also enabled calculation of the main fatty acids and their compositions in a simple manner from the TAG profiles; the results are found to be very similar to the prevailing methods of derivatization using GC/MS. This study depicts the potential of MALDI-TOF/MS as an easy, fast, and reliable technique to characterize the TAG and FAPs in vegetable oils.


Assuntos
Ácidos Graxos/análise , Óleos de Plantas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Triglicerídeos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas
13.
J Agric Food Chem ; 57(4): 1135-42, 2009 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19199592

RESUMO

Triacylglycerols (TAGs), composed of three esterified fatty acids with an attached glycerol backbone, are the main component of vegetable oil (approximately 95%) and an important source of energy and nutrition for humans, so their compositional analysis merits extensive interest. Intact TAG composition of oil in native form is highly important, rather than the fatty acid profile itself. This paper reports the analysis of the TAG profile of olive oils produced from the six common olive cultivars grown in the Negev desert of Israel (Barnea, Souri, Arbequina, Picual, Leccino, and Koroneiki) together with the content of some additional common oil quality parameters closely associated with TAG composition and integrity. Matrix-assisted laser ionization-desorption time-of-flight/mass spectrometry (MALDI-TOF/MS) fingerprintings were employed for TAG profiling. With 2,5-dihydroxybenzoic acid (DHB), MALDI-TOF/MS was able to fingerprint the intact TAG profiles in olive oils in a fast and easy manner without any derivatization. Triolein (31.53%) was found to be the main intact TAG followed by dioleoyl-palmitoyl (23.06%) and dioleoyl-linoleoyl (14.31%). MALDI-TOF/MS also enabled calculation of the main fatty acids and their compositions in a simple manner from the TAG profiles; the results are found to be very similar to conventional methods determined by GC and HPLC. Average free fatty acids and peroxide value were found to be less than 0.8% and 10 mequiv of O(2)/kg of oil, respectively, in all of the tested oils. Relatively high levels of tocopherols (av = 325 microg/kg) and phytosterols (av = 2375 mg/kg) were found. This study demonstrates MALDI-TOF/MS technology as an easy and fast methodology for TAG and fatty acid profile analysis in olive oils. Additionally, this study also shows the high levels of tocopherols and phytosterols in the olive oils produced from the common cultivars grown in the Israeli Negev desert.


Assuntos
Óleos de Plantas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Triglicerídeos/análise , Clima Desértico , Ácidos Graxos/análise , Israel , Olea/crescimento & desenvolvimento , Azeite de Oliva , Fitosteróis/análise , Tocoferóis/análise , Trioleína/análise
14.
Bioresour Technol ; 100(3): 1221-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18848776

RESUMO

The aim of this study was to assess the suitability of Desert date (Balanites aegyptiaca L. Delile) as an oil crop in arid lands for large-scale sustainable industrial biodiesel production. Characterization of the Desert date plant material showed that using proper cultivation practices with emphasis on low quality irrigation water trees can be extremely well developed in hyper-arid conditions of the Israeli Arava desert and yield oil-rich fruits. Best selected trees can yield date fruits up to 52 kg/trees. Desert date kernels oil content may reach up to 46.7% (based on dry weight). The oil is consisted on four major fatty acids: palmitic (16:0), stearic (18:0), oleic (18:1), and linoleic (18:2), constituting 98-100% of the total fatty acids in the oil of all tested genotypes. Linoleic acid was the most prevalent fatty acid, ranging from 31% to 51% of the fatty acids profile, very similar to soybean oil profile. In situ biodiesel production directly from oil-enriched powder was successfully developed. Yield efficiency for both conventional and in situ biodiesel production was about 90%. The qualities of the produced biodiesel well meet the international biodiesel standards. The present study clearly demonstrated Desert date as a model for the utilization of bioresources in the Israeli Arava desert and potentially other similar areas for cost-effective biodiesel production.


Assuntos
Balanites/química , Fontes de Energia Bioelétrica , Conservação dos Recursos Naturais/métodos , Frutas/química , Gasolina , Óleos de Plantas/química , Esterificação
15.
FEMS Microbiol Ecol ; 64(3): 378-87, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18393989

RESUMO

Recent evidence suggests that there is a dynamic microbial biota living on the surface and in the mucus layer of many hermatypic coral species that plays an essential role in coral well-being. Most of the studies published to date emphasize the importance of prokaryotic communities associated with the coral mucus in coral health and disease. In this study, we report the presence of a protist (Fng1) in the mucus of the hermatypic coral Fungia granulosa from the Gulf of Eilat. This protist was identified morphologically and molecularly as belonging to the family Thraustochytridae (phylum Stramenopile, order Labyrinthulida), a group of heterotrophs widely distributed in the marine environment. Morphological examination of this strain revealed a nonmotile organism c. 35 mum in diameter, which is able to thrive on carbon-deprived media, and whose growth and morphology are inoculum dependent. Its fatty acid production profile revealed an array of polyunsaturated fatty acids. A similar protist was also isolated from the mucus of the coral Favia sp. In light of these findings, its possible contribution to the coral holobiont is discussed.


Assuntos
Antozoários/parasitologia , Eucariotos/classificação , Eucariotos/isolamento & purificação , Aminoácidos/metabolismo , Animais , Metabolismo dos Carboidratos , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Eucariotos/citologia , Eucariotos/genética , Eucariotos/ultraestrutura , Ácidos Graxos/análise , Microscopia , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
16.
Bioresour Technol ; 99(5): 1165-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17433667

RESUMO

Seeking an alternative approach for producing a larvicidal product from Balanites aegyptiaca plants, callus was produced from in vitro cultures of root explants and its larvicidal activity against Aedes aegypti mosquito larvae was evaluated. Concentrations of 0, 50, 100, 500, 1000, and 1500 ppm of saponins from the root-derived callus of B. aegyptiaca were used to determine larvicidal effects and consequent effect on adult emergence. A dose-dependent effect was observed. In a chronic mortality assessment (after 7 days of exposure), concentrations of 500 ppm or greater killed 100% of the test larvae population. Fifty parts per million showed no difference in larval mortality compared to the control (0 ppm); however, this concentration allowed one-fourth of the adult emergence of the control treatment. These results suggest that saponins from in vitro cultures of the root explant of B. aegyptiaca can be used as a larvicidal agent against A. aegypti larvae.


Assuntos
Aedes/efeitos dos fármacos , Balanites/química , Inseticidas/química , Inseticidas/farmacologia , Saponinas/química , Saponinas/farmacologia , Animais , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Estrutura Molecular
17.
J Agric Food Chem ; 55(25): 10405-13, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18004807

RESUMO

Pomegranate oil (PGO) is a unique and quite rare edible oil produced from Punica granatum L. seeds. It is considered to be a powerful health-benefiting agent, due to its antioxidative, anticancer, and antilipidemic properties. The aim of this study was to achieve a comprehensive and detailed profile of the different components of PGO. The fatty acid profile and phytosterol composition were determined by GC-MS; the triacylglycerol (TAG) compositions were profiled by the mass spectrometry tool of MALDI-TOF/MS. Results showed linolenic acid (18:3) to be the predominant fatty acid in the PGO (64-83%), as previously reported. The linolenic acid fraction was composed of four different chromatographically separated peaks that are assumed, according to MS data (based on both FAME and DMOX derivatization), to be attributed to different geometric isomers of conjugated linolenic acid (CLNA), punicic acid (18:3: 9-cis,11-trans,13-cis) being the major isomer. The MALDI-TOF/MS finger printing results showed the different TAG compositions present in the PGO, the major ones being LnLnLn and LnLnP. This unique PGO TAG fingerprint enables it to be differentiated from most other common edible oils. Phytosterols were found in quite a high concentration in the PGO (4089-6205 mg/kg), about 3-4-fold higher than in soybean oil. A detailed profile of the phytosterols in the PGO showed a wide variety, the major phytosterols being beta-sitosterol, campesterol, and stigmasterol. This study depicts a new detailed analysis of PGO, showing great potential for further research regarding the physiological effects of specific valuable components in pomegranate oil.


Assuntos
Lythraceae/química , Óleos de Plantas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Triglicerídeos/análise , Ácidos Graxos/análise , Frutas/química , Fitosteróis/análise , Ácido alfa-Linolênico/análise
18.
Phytochem Anal ; 18(4): 354-62, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17623371

RESUMO

The kernel cake produced from Balanites aegyptiaca fruit of Israeli origin was analysed for its saponin constituents using high-performance liquid chromatography-mass spectrometry (HPLC-MS). The HPLC was equipped with a reversed-phase C18 column and a refractive index detector (RID), and elution was isocratic with methanol and water (70:30). The MS system was equipped with electrospray ionisation (ESI). Nine compounds were chromatographically separated, their masses were determined in the negative ion mode and subsequent fragmentation of each component was carried out. From the nine components, six saponins with molecular masses of 1196, 1064, 1210, 1224, 1078 and 1046 Da were identified, with the compound of mass 1210 Da being the main saponin (ca. 36%). Saponins with masses of 1224 and 1046 Da have not been previously reported in B. aegyptiaca. In all saponins, diosgenin was found to be the sole aglycone. This study shows that HPLC-ESI/MS is a quick and reliable technique for characterizing the saponins from kernel cake of B. aegyptiaca.


Assuntos
Balanites/química , Frutas/química , Saponinas/análise , Saponinas/química , Sementes/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
19.
J Biotechnol ; 130(1): 85-94, 2007 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-17442442

RESUMO

Novel cationic amphiphilic compounds were prepared from vernonia oil, a natural epoxidized triglyceride, and studied with respect to vesicle formation, encapsulation of biomaterials such as DNA, and their physical stability and transport through isolated plant cuticle membranes. The amphiphiles studied were a single-headed compound III (a quaternary ammonium head group with two alkyl chains) and a triple-headed compound IV, which is essentially three molecules of compound III bound together through a glycerol moiety. Vesicles of the two amphiphiles, prepared by sonication in water and solutions of uranyl acetate or the herbicide 2,4-D (2,4-dichloropenoxy acetic acid), were examined by TEM, SEM, AFM, and confocal laser systems and had a spherical shape which encapsulated the solutes with diameters between 40 and 110 nm. Vesicles from amphiphile IV could be made large enough to encapsulate a condensed 5.2kb DNA plasmid (pJD328). Vesicles of amphiphile IV were also shown to pass intact across isolated plant cuticle membranes and the rate of delivery of encapsulated radio-labeled 2,4-D through isolated plant cuticle membranes obtained with these vesicles was clearly greater in comparison to liposomes prepared from dipalmitopyl phosphatidylcholine (DPPC) and the control, nonencapsulated 2,4-D. Vesicles from amphiphiles III and IV were found to be more stable than those of liposomes from DPPC. The data indicate the potential of vesicles prepared from the novel amphiphile IV to be a relatively efficient nano-scale delivery system to transport DNA and other bioactive agents through plant biological barriers. This scientific approach may open the way for further development of efficient in vivo plant transformation systems.


Assuntos
Biotecnologia/métodos , Técnicas de Transferência de Genes , Genes de Plantas , Óleos de Plantas/farmacocinética , Vernonia , Radioisótopos de Carbono , Cátions/química , Cátions/farmacocinética , Parede Celular/metabolismo , Microscopia Eletrônica de Transmissão , Óleos de Plantas/química , Plasmídeos/farmacocinética , Vesículas Transportadoras/ultraestrutura
20.
J Agric Food Chem ; 54(17): 6277-85, 2006 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-16910720

RESUMO

With growing use of synthetic adjuvants in modern agriculture, their impacts on the environment are being questioned. In a search for an environmentally safe phyto-adjuvant, we have investigated natural glycosidic saponin for delivery of agromaterials through plant cuticle membranes. Four saponin preparations from Quillaja saponaria bark (QE), obtained from Sigma-Aldrich, and Balanites aegyptiaca fruit mesocarp (ME), kernel (KE), and root (RE), isolated and characterized in our laboratory, were used for testing the delivery of [14C]-2,4-dichlorophenoxyacetic acid (2,4-D) across isolated intact astomatous adaxial Citrus grandis leaf cuticle membranes (CMs). The results showed that both Q. saponaria and B. aegyptiaca saponin preparations enhanced delivery of 2,4-D through CMs. Among the saponin preparations, ME exhibited a significantly higher level of delivery of 2,4-D with a concentration effect (2% being the highest). Transmission electron microscope (TEM) and dynamic light scattering (DLS) characterization of these saponin preparations in aqueous solution clearly demonstrated the formation of nanoscale vesicles. Various possibilities for a natural amphiphatic phyto-saponin as a delivery adjuvant through CMs are discussed.


Assuntos
Agroquímicos/administração & dosagem , Folhas de Planta/metabolismo , Folhas de Planta/ultraestrutura , Plantas/metabolismo , Plantas/ultraestrutura , Saponinas/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/metabolismo , Agroquímicos/metabolismo , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Saponinas/química
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