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Iryna Smetanska - One of the best experts on this subject based on the ideXlab platform.
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determination of lignans phenolic acids and antioxidant capacity in transformed hairy root culture of Linum Usitatissimum
Natural Product Research, 2018Co-Authors: Ahmed M M Gabr, Hoda B Mabrok, Emam A Abdelrahim, Mohamed Kamal Elbahr, Iryna SmetanskaAbstract:Hairy root culture is a promising alternative method for the production of secondary metabolites. In this study, transformed root of Linum Usitatissimum was established using Agrobacterium rhizogen...
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Lignan accumulation in callus and Agrobacterium rhizogenes-mediated hairy root cultures of flax (Linum Usitatissimum)
Plant Cell Tissue and Organ Culture (PCTOC), 2016Co-Authors: Ahmed M M Gabr, Hoda B Mabrok, Kadry Z. Ghanem, Michael Blaut, Iryna SmetanskaAbstract:Agrobacterium rhizogenes is gaining intensity in research to develop and produce a large number of commercially important secondary metabolites, such as lignans. Worldwide, lignans are receiving great attention because of their putative beneficial effects on human health. In this study, we investigated the potential of callus and A. rhizogenes , hairy roots, of flax Linum Usitatissimum in accumulating lignans, namely, secoisolariciresinol diglucoside (SDG), secoisolariciresinol (SECO) and matairesinol (MAT). Callus cultures were established on Gamborg B5 medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) alone or in combination with 6-benzyladenine or gibberellic acid (GA3). These callus cultures were transformed with A. rhizogenes , which were initiated on 1.0 mg l^−1 2,4-D + 0.5 mg l^−1 GA3 or 1.0 mg l^−1 GA3 media. Both hairy root culture 1 and hairy root culture 2 accumulated SDG, SECO and MAT with a total lignan concentration of 1.227 and 1.057 µmol g^−1, respectively. However, non-transformed cultures did not accumulate MAT but accumulated SECO. Determination of total phenolic content by high-performance liquid chromatography revealed higher phenolic acid content in hairy root cultures compared with that in non-transformed cultures. Antioxidant activity, as measured by 2,2-diphenyl-1-picryl-hydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid-free radical scavenging assays, was significantly higher in hairy root cultures than in non-transformed cultures. Furthermore, the extract of hairy root culture showed inhibition of proliferation of human breast cancer cell line (MCF-7).
Ahmed M M Gabr - One of the best experts on this subject based on the ideXlab platform.
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determination of lignans phenolic acids and antioxidant capacity in transformed hairy root culture of Linum Usitatissimum
Natural Product Research, 2018Co-Authors: Ahmed M M Gabr, Hoda B Mabrok, Emam A Abdelrahim, Mohamed Kamal Elbahr, Iryna SmetanskaAbstract:Hairy root culture is a promising alternative method for the production of secondary metabolites. In this study, transformed root of Linum Usitatissimum was established using Agrobacterium rhizogen...
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Lignan accumulation in callus and Agrobacterium rhizogenes-mediated hairy root cultures of flax (Linum Usitatissimum)
Plant Cell Tissue and Organ Culture (PCTOC), 2016Co-Authors: Ahmed M M Gabr, Hoda B Mabrok, Kadry Z. Ghanem, Michael Blaut, Iryna SmetanskaAbstract:Agrobacterium rhizogenes is gaining intensity in research to develop and produce a large number of commercially important secondary metabolites, such as lignans. Worldwide, lignans are receiving great attention because of their putative beneficial effects on human health. In this study, we investigated the potential of callus and A. rhizogenes , hairy roots, of flax Linum Usitatissimum in accumulating lignans, namely, secoisolariciresinol diglucoside (SDG), secoisolariciresinol (SECO) and matairesinol (MAT). Callus cultures were established on Gamborg B5 medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) alone or in combination with 6-benzyladenine or gibberellic acid (GA3). These callus cultures were transformed with A. rhizogenes , which were initiated on 1.0 mg l^−1 2,4-D + 0.5 mg l^−1 GA3 or 1.0 mg l^−1 GA3 media. Both hairy root culture 1 and hairy root culture 2 accumulated SDG, SECO and MAT with a total lignan concentration of 1.227 and 1.057 µmol g^−1, respectively. However, non-transformed cultures did not accumulate MAT but accumulated SECO. Determination of total phenolic content by high-performance liquid chromatography revealed higher phenolic acid content in hairy root cultures compared with that in non-transformed cultures. Antioxidant activity, as measured by 2,2-diphenyl-1-picryl-hydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid-free radical scavenging assays, was significantly higher in hairy root cultures than in non-transformed cultures. Furthermore, the extract of hairy root culture showed inhibition of proliferation of human breast cancer cell line (MCF-7).
Francois Mesnard - One of the best experts on this subject based on the ideXlab platform.
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Use of qNMR for speciation of flaxseeds (Linum Usitatissimum) and quantification of cyanogenic glycosides
Analytical and Bioanalytical Chemistry, 2017Co-Authors: Romain Roulard, Jean-xavier Fontaine, Arash Jamali, Dominique Cailleu, Reynald Tavernier, Xavier Guillot, Larbi Rhazi, Emmanuel Petit, Roland Molinie, Francois MesnardAbstract:This report describes a routine method taking less than 20 min to quantify cyanogenic glycosides such as linustatin and neolinustatin from flaxseeds ( Linum Usitatissimum L.) using ^1H nuclear magnetic resonance. After manual dehulling, a higher linustatin content was shown in the almond fraction, while neolinustatin and total cyanogenic glycoside contents were significantly higher in hulls. Linustatin and neolinustatin were quantified in seven cultivars grown in two locations in three different years. Linustatin, neolinustatin, and total cyanogenic glycosides ranged between 91 and 267 mg/100 g, 78–272 mg/100 g, and 198–513 mg/100 g dry weight flaxseeds, respectively. NMR revealed differences of up to 70% between samples with standard deviation variations lower than 6%. This study shows that NMR is a very suitable tool to perform flaxseed varietal selection for the cyanogenic glycoside content. Graphical abstract qNMR can be used to perform flaxseed varietal selection for the cyanogenic glycoside content.
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pinoresinol lariciresinol reductase gene expression and secoisolariciresinol diglucoside accumulation in developing flax Linum Usitatissimum seeds
Planta, 2006Co-Authors: Christophe Hano, Ophelie Fliniaux, Frederic Lamblin, Randolph R.j. Arroo, B. Legrand, Francois Mesnard, I Martin, Laurent Gutierrez, Eric LaineAbstract:The transcription activity of the pinoresinol–lariciresinol reductase (PLR) gene of Linum Usitatissimum (so-called LuPLR), a key gene in lignan synthesis, was studied by RT-PCR and promoter–reporter transgenesis. The promoter was found to drive transcription of a GUSint reporter gene in the seed coats during the flax seed development. This fitted well with the tissue localization monitored by semi-quantitative RT-PCR of LuPLR expression. Accumulation of the main flax lignan secoisolariciresinol diglucoside was coherent with LuPLR expression during seed development. This three-way approach demonstrated that the LuPLR gene is expressed in the seed coat of flax seeds, and that the synthesis of PLR enzyme occurs where flax main lignan is found stored in mature seeds, confirming its involvement in SDG synthesis.
Ophelie Fliniaux - One of the best experts on this subject based on the ideXlab platform.
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RNAi-mediated pinoresinol lariciresinol reductase gene silencing in flax (Linum Usitatissimum L.) seed coat: Consequences on lignans and neolignans accumulation
Journal of Plant Physiology, 2014Co-Authors: Sullivan Renouard, Ophelie Fliniaux, Frederic Lamblin, Herve Demailly, Marie-aude Tribalatc, Gaëlle Mongelard, Cyrielle Corbin, Djurdjica Marosevic, Serge Pilard, Laurent GutierrezAbstract:RNAi technology was applied to down regulate LuPLR1 gene expression in flax (Linum Usitatissimum L.) seeds. This gene encodes a pinoresinol lariciresinol reductase responsible for the synthesis of (+)-secoisolariciresinol diglucoside (SDG), the major lignan accumulated in the seed coat. If flax lignans biological properties and health benefits are well documented their roles in planta remain unclear. This loss of function strategy was developed to better understand the implication of the PLR1 enzyme in the lignan biosynthetic pathway and to provide new insights on the functions of these compounds. RNAi plants generated exhibited LuPLR1 gene silencing as demonstrated by quantitative RT-PCR experiments and the failed to accumulate SDG. The accumulation of pinoresinol the substrate of the PLR1 enzyme under its diglucosylated form (PDG) was increased in transgenic seeds but did not compensate the overall loss of SDG. The monolignol flux was also deviated through the synthesis of 8-5' linked neolignans dehydrodiconiferyl alcohol glucoside (DCG) and dihydro-dehydrodiconiferyl alcohol glucoside (DDCG) which were observed for the first time in flax seeds.
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Microwave-assisted extraction of herbacetin diglucoside from flax (Linum Usitatissimum L.) seed cakes and its quantification using RP-HPLC-UV system.
Molecules, 2014Co-Authors: Ophelie Fliniaux, C. Corbin, A. Ramsay, S. Renouard, V. Beejmohun, J. Doussot, A. Falguieres, C. Ferroud, F. Lamblin, E. LaineAbstract:Flax (Linum Usitatissimum L.) seeds are widely used for oil extraction and the cold-pressed flaxseed (or linseed) cakes obtained during this process constitute a valuable by-product. The flavonol herbacetin diglucoside (HDG) has been previously reported as a constituent of the flaxseed lignan macromolecule linked through ester bonds to the linker molecule hydroxymethylglutaric acid. In this context, the development and validation of a new approach using microwave-assisted extraction (MAE) of HDG from flaxseed cakes followed by quantification with a reverse-phase HPLC system with UV detection was purposed. The experimental parameters affecting the HDG extraction yield, such as microwave power, extraction time and sodium hydroxide concentration, from the lignan macromolecule were optimized. A maximum HDG concentration of 5.76 mg/g DW in flaxseed cakes was measured following an irradiation time of 6 min, for a microwave power of 150 W using a direct extraction in 0.1 M NaOH in 70% (v/v) aqueous methanol. The optimized method was proven to be rapid and reliable in terms of precision, repeatability, stability and accuracy for the extraction of HDG. Comparison with a conventional extraction method demonstrated that MAE is more effective and less time-consuming.
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pinoresinol lariciresinol reductase gene expression and secoisolariciresinol diglucoside accumulation in developing flax Linum Usitatissimum seeds
Planta, 2006Co-Authors: Christophe Hano, Ophelie Fliniaux, Frederic Lamblin, Randolph R.j. Arroo, B. Legrand, Francois Mesnard, I Martin, Laurent Gutierrez, Eric LaineAbstract:The transcription activity of the pinoresinol–lariciresinol reductase (PLR) gene of Linum Usitatissimum (so-called LuPLR), a key gene in lignan synthesis, was studied by RT-PCR and promoter–reporter transgenesis. The promoter was found to drive transcription of a GUSint reporter gene in the seed coats during the flax seed development. This fitted well with the tissue localization monitored by semi-quantitative RT-PCR of LuPLR expression. Accumulation of the main flax lignan secoisolariciresinol diglucoside was coherent with LuPLR expression during seed development. This three-way approach demonstrated that the LuPLR gene is expressed in the seed coat of flax seeds, and that the synthesis of PLR enzyme occurs where flax main lignan is found stored in mature seeds, confirming its involvement in SDG synthesis.
Norman G Lewis - One of the best experts on this subject based on the ideXlab platform.
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biosynthetic pathway to the cancer chemopreventive secoisolariciresinol diglucoside hydroxymethyl glutaryl ester linked lignan oligomers in flax Linum Usitatissimum seed
Journal of Natural Products, 2001Co-Authors: Joshua D Ford, Laurence B Davin, Kaisheng Huang, Huaibin Wang, Norman G LewisAbstract:Application of stable and radioisotope precursor/tracer experiments resulted in the identification of various phenylpropanoid, monolignol, and lignan metabolites involved in the biosynthesis of the cancer chemopreventive secoisolariciresinol diglucoside (SDG; 1)-containing ester-linked “polymer(s)” in flax (Linum Usitatissimum) seed. Individual analysis of size-segregated flax seed capsules at five early stages of their development provided a metabolic profile of intermediates leading to “biopolymer” biosynthesis. The use of 1H and 13C NMR and HRMS analyses resulted in the identification of 6a-HMG (hydroxymethyl glutaryl) SDG (17) and 6a,6a‘-di-HMG SDG (18) as the two major components of the ester-linked “biopolymer(s)”. Based on metabolic tracer analyses and relative radioisotopic incorporations throughout each of these five stages of seed development, a biochemical pathway is proposed from phenylalanine to SDG (1), with subsequent mono- and di-substitutions of SDG (1) with HMG CoA. These metabolites the...
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biosynthetic pathway to the cancer chemopreventive secoisolariciresinol diglucoside hydroxymethyl glutaryl ester linked lignan oligomers in flax Linum Usitatissimum seed
Journal of Natural Products, 2001Co-Authors: Joshua D Ford, Laurence B Davin, Kaisheng Huang, Huaibin Wang, Norman G LewisAbstract:Application of stable and radioisotope precursor/tracer experiments resulted in the identification of various phenylpropanoid, monolignol, and lignan metabolites involved in the biosynthesis of the cancer chemopreventive secoisolariciresinol diglucoside (SDG; 1)-containing ester-linked "polymer(s)" in flax (Linum Usitatissimum) seed. Individual analysis of size-segregated flax seed capsules at five early stages of their development provided a metabolic profile of intermediates leading to "biopolymer" biosynthesis. The use of (1)H and (13)C NMR and HRMS analyses resulted in the identification of 6a-HMG (hydroxymethyl glutaryl) SDG (17) and 6a,6a'-di-HMG SDG (18) as the two major components of the ester-linked "biopolymer(s)". Based on metabolic tracer analyses and relative radioisotopic incorporations throughout each of these five stages of seed development, a biochemical pathway is proposed from phenylalanine to SDG (1), with subsequent mono- and di-substitutions of SDG (1) with HMG CoA. These metabolites then serve as precursors for formation of the SDG-HMG ester-linked oligomers. Results from this study will facilitate future isolation and characterization of the proteins and enzymes involved in biosynthesis of the SDG-HMG ester-linked oligomers in flax seed.