Propagação in vitro e aclimatização de Lippia rotundifolia, uma espécie endêmica dos Campos Rupestres Brasileiros

The importance in folk medicine, combined to threats in their environment, becomes necessary to carry out studies involving large-scale propagation of Lippia genus. Although the tissue culture propagation is widely disseminated for medicinal plants, for L. rotundifolia any article was published yet. The present study aimed to establish an efficient protocol for micropropagation of L. rotundifolia. Nodal segments, taken from plants collected in the Espinhaço Range, were disinfected, and cultures were initiated on MS medium with PVPP (1 g L- 1), sucrose (3%) and agar (0.7%). The culture were maintained in a growth room at controlled conditions. Disinfestation procedures and the supply of PVPP on culture media resulted in both reduced contamination and phenol oxidation rates, with more than 90% of viable cultures. In the multiplication phase were tried different BAP and NAA combinations supplied to the MS medium. The treatment that resulted in highest multiplication rates was 0.33 µM BAP. The effects of NAA were evaluated for in vitrorooting. At 0.44 µM, rooting was 70% higher than that observed in the control. The acclimatization was held in trays with substrate, coated with translucent plastic and kept under shade. The plantlets were transferred to the greenhouse after 15 days and transplanted to plant beds after 30 days. The acclimatized plantlets bloomed one year after the transference to field conditions, showing that the in vitro culture did not affect the vegetative and reproductive development, which confirms the potential of micropropagation to reduce the extinction risk of L. rotundifolia.A importância na medicina popular, assim como as ameaças em seu ambiente, tornam necessária a realização de estudos envolvendo a propagação em larga escala de plantas do gênero Lippia. Embora a propagação in vitro seja amplamente disseminada para plantas medicinais, nenhum artigo foi publicado ainda com L. rotundifolia. O presente estudo teve como objetivo estabelecer um protocolo eficiente para a micropropagação dessa espécie. Segmentos nodais, retirados de plantas coletadas na Cadeia do Espinhaço, foram desinfetados antes da inoculação em meio MS suplementado com PVPP (1 g L-1), sacarose (3%) e ágar (0,7%). Os tubos de ensaio foram mantidos em sala de crescimento sob condições controladas. O tratamento de desinfestação e a adição de PVPP aos meios de cultura resultaram na redução da infecção microbiológica assim como nas taxas de oxidação fenólica, proporcionando mais de 90% de culturas assépticas e viáveis . Na fase de multiplicação foram testadas diferentes combinações de BAP e ANA adicionadas ao meio MS. O tratamento que resultou em maiores taxas de multiplicação foi de 0,33 µM de BAP. Os efeitos do ANA foram avaliados no enraizamento in vitro. A 0,44 µM de ANA, o enraizamento foi 70% superior ao observado no controle. A aclimatização foi realizada em bandejas com substrato, revestidas com plástico translúcido e mantidas à sombra. As plantas foram transferidas para casa de vegetação após 15 dias e transplantadas para canteiros após 30 dias. As plantas aclimatizadas floresceram após um ano da transferência para condições de campo, demonstrando que os procedimentos de cultivo in vitro não afetaram o desenvolvimento vegetativo e reprodutivo das plantas, o que confirma o potencial da micropropagação para redução dos riscos de extinção de L. rotundifolia

A metabonomic study of transgenic maize (Zea mays) seeds revealed variations in osmolytes and branched amino acids

The aim of the research was to investigate metabolic variations associated with genetic modifications in the grains of Zea mays using metabonomic techniques. With this in mind, the non-targeted characteristic of the technique is useful to identify metabolites peculiar to the genetic modification and initially undefined. The results obtained showed that the genetic modification, introducing Cry1Ab gene expression, induces metabolic variations involving the primary nitrogen pathway. Concerning the methodological aspects, the experimental protocol used has been applied in this field for the first time. It consists of a combination of partial least square-discriminant analysis and principal component analysis. The most important metabolites for discrimination were selected and the metabolic correlations linking them are identified. Principal component analysis on selected signals confirms metabolic variations, highlighting important details about the changes induced on the metabolic network by the presence of a Bt transgene in the maize genome

An NMR spectroscopy study of bendaline-albumin interactions

The complete assignment of the H-1 and C-13 NMR spectra of bendaline (BNDL) was performed by mono-dimensional and homo- and hetero-correlated two-dimensional NMR experiments. The interaction between bendaline and albumin was also studied by the analysis of the motional parameters spin-lattice relaxation times, allowing the motional state of the BNDL free and bound with albumin to be defined. In absence of albumin the indazolacetic and benzylic moieties are characterized by roughly the same mobility and by positive sigma (cross-relaxation rates) values. In the presence of the macromolecule, the indazolacetic and benzylic moieties and the lysine change their motional behaviour to different extents, as indicated by correlation times. Data obtained in absence and in presence of the protein show that the molecular moiety of the bendaline most involved in the binding with albumin is the fragment H-4 H-5. The binding constant was evaluated at 2.4 x 10(3) M-1. (C) 2003 Elsevier Science (USA). All rights reserved

Organometallic Platinum(II) and Palladium(II) Polymers Containing 2,6-Diethynyl-4-nitroaniline Bridging Spacer and Related Dinuclear Model Complexes

The metal−carbon coupling in dehydrohalogenation conditions between Pt(II) or Pd(II) square planar bisphosphine dichloride complexes and 2,6-diethynyl-4-nitroaniline (DENA) yielded organometallic polymers, i.e., −[M(PTol3)2(−CC−R−CC−)]n− with R = p-NH2C6H2NO2 and M = Pt(II) or Pd(II). Dinuclear platinum complexes were also synthesized as geometrical models. The polymers and complexes were fully characterized by means of spectroscopic techniques. Accurate investigations with 2D nuclear magnetic resonance (NMR) spectroscopy were used to define the chemical and spatial structure of the polymeric chains as a helical conformation for both Pt(II)- and Pd(II)-based organometallic polymers. Optical absorption studies and X-ray photoelectron spectroscopy measurements revealed the extent of conjugation and the nature of the ending groups

In vitro propagation and acclimatization of Lippia rotundifolia, an endemic species of Brazilian Campos Rupestres

ABSTRACTThe importance in folk medicine, combined to threats in their environment, becomes necessary to carry out studies involving large-scale propagation of Lippia genus. Although the tissue culture propagation is widely disseminated for medicinal plants, for L. rotundifolia any article was published yet. The present study aimed to establish an efficient protocol for micropropagation of L. rotundifolia. Nodal segments, taken from plants collected in the Espinhaço Range, were disinfected, and cultures were initiated on MS medium with PVPP (1 g L- 1), sucrose (3%) and agar (0.7%). The culture were maintained in a growth room at controlled conditions. Disinfestation procedures and the supply of PVPP on culture media resulted in both reduced contamination and phenol oxidation rates, with more than 90% of viable cultures. In the multiplication phase were tried different BAP and NAA combinations supplied to the MS medium. The treatment that resulted in highest multiplication rates was 0.33 µM BAP. The effects of NAA were evaluated for in vitrorooting. At 0.44 µM, rooting was 70% higher than that observed in the control. The acclimatization was held in trays with substrate, coated with translucent plastic and kept under shade. The plantlets were transferred to the greenhouse after 15 days and transplanted to plant beds after 30 days. The acclimatized plantlets bloomed one year after the transference to field conditions, showing that the in vitro culture did not affect the vegetative and reproductive development, which confirms the potential of micropropagation to reduce the extinction risk of L. rotundifolia

La Región: La Región - Epoca 2ª Año XII Número 4331 - 1935 noviembre 16 (16/11/1935)

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