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Plant Physiol Biochem ; 108: 191-202, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27448793


Silymarin, a Silybum marianum seed extract containing a mixture of flavonolignans including silybin, is being used as an antihepatotoxic therapy for liver diseases. In this study, the enhancing effect of gamma irradiation on plant growth parameters of S. marianum under salt stress was investigated. The effect of gamma irradiation, either as a single elicitor or coupled with salinity, on chalcone synthase (CHS) gene expression and silybin A + B yield was also evaluated. The silybin A + B content in S. marianum fruits was estimated by liquid chromatography-mass spectrometry (LC-MS/MS). An increase in silybin content was accompanied by up-regulation of the CHS1, CHS2 and CHS3 genes, which are involved in the silybin biosynthetic pathway. The highest silybin A + B production (0.77 g/100 g plant DW) and transcript levels of the three studied genes (100.2-, 91.9-, and 24.3-fold increase, respectively) were obtained with 100GY gamma irradiation and 4000 ppm salty water. The CHS2 and CHS3 genes were partially sequenced and submitted to the NCBI database under the accession numbers KT252908.1 and KT252909.1, respectively. Developing new approaches to stimulate silybin biosynthetic pathways could be a useful tool to potentiate the use of plants as renewable resources of medicinal compounds.

Aciltransferases/genética , Cardo Mariano/genética , Silimarina/metabolismo , Aciltransferases/metabolismo , Frutas/genética , Frutas/metabolismo , Raios gama , Regulação da Expressão Gênica de Plantas , Germinação , Cardo Mariano/metabolismo , Cardo Mariano/efeitos da radiação , Família Multigênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Salinidade , Tolerância ao Sal , Sementes/crescimento & desenvolvimento , Silibina , Silimarina/genética
Gene ; 533(1): 313-21, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24045133


Pilosocereus robinii is a rare species which is experiencing sudden population collapse. Identifying and developing effective conservation and management strategies to halt the forestall extinction of this species is crucial. The present study was conducted to assess the best conditions for in vitro propagation of this plant in regard to its morphogenic, genetic as well as the chemical potentials. A successful in vitro propagation system of P. robinii has been developed. MS hormone-free medium induced the best root morphogenic potential. The plants were acclimatized in the greenhouse at 100% survival rate. Besides, the somaclonal variations between the in vitro raised plants were analyzed using PCR-ISSR markers and SDS-PAGE protein, where the regenerated explants on MS medium supplemented with TDZ were the highest in inducing new specific marker bands. Sh6 ISSR primer showed the highest polymorphism value, 81.8% with 33 total amplified fragments, while Sh3 ISSR primer showed the lowest value with polymorphic percentage of 14.3%. Furthermore, SDS-PAGE protein analysis showed no variation in protein pattern of the studied treatments. On the other side, HPLC analysis of the in vitro plantlets extracts has shown that 2iP based treatments were the highest in organic acids accumulation, while the phenolic constituents' accumulation was found to reach its peak in the BA based treatments.

Cactaceae/genética , Cromatografia Líquida de Alta Pressão/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Cactaceae/química , Cactaceae/fisiologia , Malatos/química , Fenóis/análise , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Regeneração
Physiol Mol Biol Plants ; 19(1): 127-36, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24381444


Silybum marianum L. extracts are being used as antihepatotoxic therapy for liver diseases. Silymarin is a polyphenolic flavonoid mixture isolated from milk thistle which is believed to be responsible for the plant's hepatoprotective action. Regeneration of Silybum marianum plants from shoot tip explants and assessment of their morphogenic potential, silymarin total concentration and its major constituents upon exposure to medium composition alteration and different elicitors' application was targeted. Different concentrations of NaCl, quercetin, gamma irradiation and dried fungal extracts were used to elicit silymarin production in the cultures. The chemical composition of silymarin and its total concentration was investigated through HPLC at all the experiment stages. Multiple shoots were recorded after 3 weeks of culture on MS medium containing various concentrations of BA and/or NAA. IAA was more effective than NAA and IBA in inducing robust roots in shoot cultures. The flowering plants recorded 20 % and 40 % of the total plants number in the multiplication and rooting stages respectively. The highest total silymarin concentration reached its peak with (10 Gy) gamma-irradiation to be 6.598 % dry weight in the in vitro regenerated shoot tip explants. The in vitro grown flowers showed 1.7 times more sylimarin productivity as compared to that of the wild grown congruent.

Planta ; 235(2): 359-73, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21909761


Constitutive expression of the FPF1 gene in hybrid aspen (Populus tremula L. × P. tremuloides Michx.) showed a strong effect on wood formation but no effect on flowering time. Gene expression studies showed that activity of flowering time genes PtFT1, PtCO2, and PtFUL was not increased in FPF1 transgenic plants. However, the SOC1/TM3 class gene PTM5, which has been related to wood formation and flowering time, showed a strong activity in stems of all transgenic lines studied. Wood density was lower in transgenic plants, despite significantly reduced vessel frequency which was overcompensated by thinner fibre cell walls. Chemical screening of the wood by pyrolysis GC/MS showed that FPF1 transgenics have higher fractions of cellulose and glucomannan products as well as lower lignin content. The latter observation was confirmed by UV microspectrophotometry on a cellular level. Topochemical lignin distribution revealed a slower increase of lignin incorporation in the developing xylem of the transgenics when compared with the wild-type plants. In line with the reduced wood density, micromechanical wood properties such as stiffness and ultimate stress were also significantly reduced in all transgenic lines. Thus, we provide evidence that FPF1 class genes may play a regulatory role in both wood formation and flowering in poplar.

Proteínas de Arabidopsis/química , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Populus/química , Madeira/fisiologia , Agrobacterium tumefaciens/química , Agrobacterium tumefaciens/genética , Proteínas de Arabidopsis/genética , Parede Celular/química , Celulose/química , Quimera/genética , Quimera/fisiologia , DNA de Plantas/genética , Flores/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Genes de Plantas , Lignina/química , Mananas/química , Microespectrofotometria/métodos , Células Vegetais/química , Caules de Planta/química , Caules de Planta/genética , Caules de Planta/fisiologia , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Populus/genética , Populus/fisiologia , Estresse Fisiológico , Propriedades de Superfície , Fatores de Tempo , Raios Ultravioleta , Madeira/química , Madeira/genética