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Raphaël Morillon - One of the best experts on this subject based on the ideXlab platform.

  • Tetraploid Citrus seedlings subjected to long-term nutrient deficiency are less affected at the ultrastructural, physiological and biochemical levels than diploid ones
    Plant Physiology and Biochemistry, 2019
    Co-Authors: Julie Oustric, François Luro, Yann Quilichini, Raphaël Morillon, Stéphane Herbette, Jean Giannettini, Liliane Berti, Jérémie Santini
    Abstract:

    Nutrient deficiency has economic and ecological repercussions for Citrus fruit crops worldwide. Citrus crops rely on fertilization to maintain good fruit output and quality, whereas new crop management policy aims to reduce fertilizers input. New rootstocks are needed to meet to this constraint, and the use of new tetraploid rootstocks better adapted to lower nutrient intake could offer a promising way forward. Here we compared physiological, biochemical and anatomic traits of leaves in diploid (2x) and doubled-diploid (4x) Citrumelo 4475 (Citrus paradisi L. Macf. × Poncirus trifoliata L. Raf.) and Volkamer lemon (Citrus Limonia Osb.) seedlings over 7 months of nutrient deficiency. Photosynthetic parameters (Pnet, Gs and Fv/Fm) decreased, but to a lesser extent in 4x genotypes than 2x. Degradation of the ultrastructural organelles (chloroplasts and mitochondria) and compound cells (thylakoids and starches) was also lower in 4x genotypes, suggesting that tetraploidy may enhance tolerance to nutrient deficiency. However, leaf surface (stomata, stomatal density and epithelial cells) showed no nutrient deficiency-induced change. In 4x Citrumelo 4475, the higher tolerance to nutrient deficiency was associated with a lower MDA and H2O2 accumulation than in the 2x, suggesting a more efficient antioxidant system in the 4x genotype. However, few differences in antioxidant system and oxidative status were observed between 2x and 4x Volkamer lemons.

  • polyploidization alters constitutive content of volatile organic compounds voc and improves membrane stability under water deficit in volkamer lemon Citrus Limonia osb leaves
    Environmental and Experimental Botany, 2016
    Co-Authors: Dayse Drielly Souza Santana Vieira, François Luro, Raphaël Morillon, Giovanni Emiliani, Marco Michelozzi, Mauro Centritto, Francesco Loreto, Abelmon Da Silva Gesteira, B E Maserti
    Abstract:

    Abstract In Citrus species chromosome doubling naturally occurs in somatic embryos and doubled diploid plants often show better adaptation to adverse environmental condition. To understand the molecular determinants of stress acclimation, we examined the response to water deficit in diploid (2×VL) and doubled diploid (4×VL) seedlings of Volkamer lemon (Citrus Limonia Osb.) assessing the profile of constitutive volatile organic compound (VOC) in control and stressed conditions. Physiological parameters and leaf volatile compound profiles were measured during water deficit and 24 h after rehydration of plants to field capacity. Net photosynthesis and stomatal conductance were reduced in water stressed leaves, with no significant differences between 2×VL and 4×VL plants. Malondialdehyde concentration, a marker of lipid peroxidation of cellular membranes, was significantly more higher in stressed 2×VL leaves than in 4×VL. The blend of constitutive VOC was different in control leaves being oxygenated monoterpenoids more abundant in 2×VL leaves, and monoterpenoids more abundant in 4×VL leaves. Water deficit did not stimulate biosynthesis of terpenoids, whereas accumulation of trans-2 hexenal, a green leaf volatile (GLV) synthesized after membrane denaturation, was observed in stressed leaves of 2×VL leaves, but not in 4×VL leaves. Semiquantitative PCR showed an increase of the expression of HPL, the gene encoding for hydroperoxidase lyase which catalyzes 2-hexenal formation, only in 2×VL plants. The expression of the putative dehydration transcription factor DREB2A was also observed only in 2×VL water stressed plants. This work shows that level of ploidy may alter constitutive content of GLV by Citrus, therefore likely affecting plants capacity of protection and interaction with other organisms. Whereas diploid and double diploid plants showed similar physiological responses to water deficit, a biochemical marker indicated that membranes of double diploid leaves were more resistant to the stress. These results provide intriguing insights into the regulation of terpenoids and oxylipins pathways as a function of polyploidization in a non-model plant species.

  • tetraploid rangpur lime rootstock increases drought tolerance via enhanced constitutive root abscisic acid production
    Plant Cell and Environment, 2013
    Co-Authors: Thierry Allario, Javier Brumos, Domingo J Iglesias, Manuel Talon, Luis Navarro, Patrick Ollitrault, Jose M Colmeneroflores, Jose Antonio Pina, Raphaël Morillon
    Abstract:

    Whole-genome duplication, or polyploidy, is common in many plant species and often leads to better adaptation to adverse environmental condition. However, little is known about the physiological and molecular determinants underlying adaptation. We examined the drought tolerance in diploid (2x) and autotetraploid (4x) clones of Rangpur lime (Citrus Limonia) rootstocks grafted with 2x Valencia Delta sweet orange (Citrus sinensis) scions, named V/2xRL and V/4xRL, respectively. Physiological experiments to study root-shoot communication associated with gene expression studies in roots and leaves were performed. V/4xRL was much more tolerant to water deficit than V/2xRL. Gene expression analysis in leaves and roots showed that more genes related to the response to water stress were differentially expressed in V/2xRL than in V/4xRL. Prior to the stress, when comparing V/4xRL to V/2xRL, V/4xRL leaves had lower stomatal conductance and greater abscisic acid (ABA) content. In roots, ABA content was higher in V/4xRL and was associated to a greater expression of drought responsive genes, including CsNCED1, a pivotal regulatory gene of ABA biosynthesis. We conclude that tetraploidy modifies the expression of genes in Rangpur lime Citrus roots to regulate long-distance ABA signalling and adaptation to stress.

  • large changes in anatomy and physiology between diploid rangpur lime Citrus Limonia and its autotetraploid are not associated with large changes in leaf gene expression
    Journal of Experimental Botany, 2011
    Co-Authors: Thierry Allario, Javier Brumos, Manuel Talon, Luis Navarro, Patrick Ollitrault, Francisco R Tadeo, Jose M Colmeneroflores, Yann Froelicher, Raphaël Morillon
    Abstract:

    Very little is known about the molecular origin of the large phenotypic differentiation between genotypes arising from somatic chromosome set doubling and their diploid parents. In this study, the anatomy and physiology of diploid (2x) and autotetraploid (4x) Rangpur lime (Citrus Limonia Osbeck) seedlings has been characterized. Growth of 2x was more vigorous than 4x although leaves, stems, and roots of 4x plants were thicker and contained larger cells than 2x that may have a large impact on cell-to-cell water exchanges. Leaf water content was higher in 4x than in 2x. Leaf transcriptome expression using a Citrus microarray containing 21 081 genes revealed that the number of genes differentially expressed in both genotypes was less than 1% and the maximum rate of gene expression change within a 2-fold range. Six up-regulated genes in 4x were targeted to validate microarray results by real-time reverse transcription-PCR. Five of these genes were apparently involved in the response to water deficit, suggesting that, in control conditions, the genome expression of Citrus autotetraploids may act in a similar way to diploids under water-deficit stress condition. The sixth up-regulated gene which codes for a histone may also play an important role in regulating the transcription of growth processes. These results show that the large phenotypic differentiation in 4x Rangpur lime compared with 2x is not associated with large changes in genome expression. This suggests that, in 4x Rangpur lime, subtle changes in gene expression may be at the origin of the phenotypic differentiation of 4x Citrus when compared with 2x.

  • large changes in anatomy and physiology between diploid rangpur lime Citrus Limonia and its autotetraploid are not associated with large changes in leaf gene expression p478
    Abstracts of Plant and Animal Genomes XIXth Conference San Diego CA (USA) January 15-19 2011, 2011
    Co-Authors: Raphaël Morillon, Thierry Allario, Javier Brumos, Jose M Colmenero, Manuel Talon, Luis Navarro, Francisco R Tadeo, Patrick Ollitrault
    Abstract:

    Polyploid genotypes present a specific anatomy and morphology compared to diploid (2x) which should have a huge impact on plant physiology. We investigated the anatomy and morphology of root and leaf of 2x and autotetraploid (4x) Rangpur lime (Citrus Limonia) seedlings grown in control condition. 4x line arose from chromosome doubling in nucellar cells of 2x Rangpur lime and has strictly the same allelic composition than the 2x one. In 4x, roots and leaves were thicker and the cell size was bigger than in 2x. Leaf stomatal conductance of 4x was lower than for 2x which could explain the smaller growth rate of 4x. Using 20 K cDNA microarrays, leaf gene expression was investigated in both genotypes. A very limited number of genes were significantly differentially expressed in both genotypes (o 1%) suggesting that subtle changes in gene expression may be at the origin of the phenotypic differentiation of 4x Citrus leaves when compared to 2x. However, investigation of candidate genes expression using qRT-PCR in roots showed that 4x Rangpur lime experienced an enhanced expression of genes involved in water deficit adaptation compared to 2x. Taking together, these results suggest that genes expression in 4x Rangpur lime is organ specific and may lead to a better adaptation to drought. (Resume d'auteur)

Elisângela Barbosa Borges Estevam - One of the best experts on this subject based on the ideXlab platform.

  • chitosan film with Citrus Limonia essential oil physical and morphological properties and antibacterial activity
    Colloids and Interfaces, 2020
    Co-Authors: Josemar Goncalves De Oliveira Filho, Elisângela Barbosa Borges Estevam, Isabella Pelosi Borges De Deus, Anna Carolina Fernandes Valadares, Cassia Cristina Fernandes, Mariana Buranelo Egea
    Abstract:

    The development of active packaging for food preservation is attracting increased attention due to serious environmental problems caused by synthetic and conventional materials. In the present study, the physical, chemical, optical, microstructural, and antibacterial properties of chitosan films with Citrus Limonia essential oil (CEO) were investigated. The incorporation >0.75% of CEO increased the thickness of the films. The incorporation >0.25% of CEO reduced the moisture content and the water vapor permeability of the chitosan films. The biodegradability of the films over ten days ranged from 55.46–62.65% and was not affected by the addition of CEO. All films showed good UV light barrier properties, and the incorporation of the CEO caused a decrease in the visible light transmission rate values. The addition of CEO changed the color of the bioactive films significantly, remain darker and yellowish. The bioactive films showed antibacterial activity against Staphylococcus aureus, but not against Escherichia coli. The films showed a heterogeneous microstructure with oil droplets retained in the continuous polysaccharide network. The results showed that chitosan films with CEO are promising as an active packaging material for food preservation.

  • composicao quimica e atividades biologicas do oleo essencial das folhas de Citrus Limonia e Citrus latifolia e dos frutos verdes e folhas de protium ovatum
    2017
    Co-Authors: Elisângela Barbosa Borges Estevam
    Abstract:

    As plantas possuem potencial terapeutico para cura de enfermidades, constituindo importante fonte de novos compostos biologicamente ativos, a partir dos metabolitos secundarios. Os oleos essenciais sao originados do metabolismo secundario das plantas, caracterizados por permitirem que os vegetais adaptem ao ambiente em que estao inseridos. Atualmente, houve crescimento da aplicacao desses oleos essenciais em industrias de alimentos, cosmeticas e farmaceuticas, no entanto, e importante ressaltar a necessidade de conhecer seus potenciais biologicos como tambem sua composicao quimica, para que possa estabelecer a correlacao entre esses potencias e a sua composicao quimica. Diante disso, objetivou-se neste estudo, determinar a composicao quimica do oleo essencial extraido das folhas de Citrus latifolia e Citrus Limonia e das folhas e frutos verdes de Protium ovatum e suas atividades antiparasitarias, bem como a atividade microbiana e citotoxica do oleo essencial das folhas de Citrus latifolia e Citrus Limonia e atividade citotoxica do oleo essencial de frutos verdes de Protium ovatum. O oleo essencial foi obtido por hidrodestilacao utilizando aparelho de clevenger. A composicao quimica foi determinada por cromatografia gasosa acoplada a espectrometro de massas (CG-EM). A atividade tripanocida foi avaliada sobre formas tripomastigotas de Trypanosoma cruzi e a atividade leishmanicida sobre as formas promastigotas do Leishmania amazonenses, a atividade citotoxica foi avaliada sobre fibroblastos e determinada pelo metodo do MTT. A atividade antibacteriana in vitro frente as bacterias Streptococcus mitis, Streptococcus mutans, Streptococcus sanguinis, Streptococcus sobrinus e Bacteroides fragilis foi determinada pelo metodo de diluicao em caldo. Quando avaliada a atividade citotoxica frente aos fibroblastos da linhagem LLCMK2, os oleos essenciais de C. latifolia (CC50 =502,9 µg.mL-1 ), C. Limonia (CC50 = 422,9 µg.mL-1 ), e dos frutos verdes de P. ovatum (CC50 = 550,3 µg.mL-1 ) apresentaram moderada citotoxicidade. Nas analises cromatograficas, foram identificados 17 constituintes quimicos para C. latifolia e 18 constituintes quimicos para C. Limonia. Os componentes principais foram limoneno, nerol e 1,8-cineol. Ja na especie P. ovatum os terpenos espatulenol, oxido de cariofileno, E–cariofileno e o mirceno foram componentes majoritarios do oleo essencial das folhas e β-mirceno, α- pineno e limoneno do oleo essencial dos frutos verdes. Os protozoarios da familia tripanossomatidea causam doencas tropicais negligenciadas como a leishmaniose e a tripanossomiase, em que os medicamentos disponiveis sao de alto custo e de grande toxicidade para o hospedeiro. Neste contexto, os oleos essenciais das folhas de C. latifolia, C. Limonia, P. ovatum e frutos verdes de P. ovatum foram avaliados frente as formas tripomastigotas da cepa Y de Trypanosoma cruzi, apresentando valores de CI50 = 51,7 µg.mL-1 , 88,2 µg.mL-1 , 5,4 µg.mL-1 e 1,2 µg.mL-1 respectivamente. A atividade leishmanicida dos oleos essenciais das folhas de C. latifolia ,C. Limonia e P. ovatum foi avaliada frente as formas promastigotas de Leishmania amazonensis, apresentando valores de CI50 = 2,03 µg.mL-1 , 2,63 µg.mL-1 e 1,56 µg.mL-1 respectivamente. O oleo essencial de C. latifolia apresentou melhor resultado frente as bacterias S. mutans, S. sanguinis CIM (100 µg. mL-1 ), enquanto o C. Limonia foi mais promissor frente a bacteria S. mitis (100 µg. mL-1 ). Em suma, os oleos essenciais das folhas de C. latifolia e C. Limonia apresentaram moderada atividade antibacteriana e os oleos essenciais das folhas e frutos verde de P. ovatum podem ser considerados excelente fonte alternativa para o desenvolvimento de novos medicamentos antiparasitarios. Este trabalho descreve pela primeira vez a composicao quimica dos oleos essenciais das folhas de Citrus Limonia e Citrus latifolia e das folhas e frutos verdes de Protium ovatum, contribuindo significativamente para o conhecimento quimico das especies e suas atividades biologicas.

  • avaliacao das atividades antibacteriana e antiparasitaria do oleo essencial das folhas de Citrus Limonia osbeck e Citrus latifolia tanaka rutaceae
    Revista Virtual de Química, 2016
    Co-Authors: Mayker Lazaro Dantas Miranda, Elisângela Barbosa Borges Estevam, Cassia Cristina Fernandes Alves, Jose Milton Alves, Paulo Pereira, Carlos Henrique Gomes Martins, Viviane Sampaio, Lizandra Guidi Magalhaes, Cristiane De Melo Cazal, Alex Fonseca Souza
    Abstract:

    O objetivo deste estudo foi avaliar o efeito antibacteriano e antiparasitario in vitro do oleo essencial das folhas de Citrus Limonia e Citrus latifolia . Foram avaliadas as atividades: antibacteriana in vitro frente as bacterias Gram-positivas e Gram-negativas e a antiparasitaria frente as formas tripomastigotas da cepa Y de Trypanosoma cruzi . De acordo com os resultados, sugere-se que o oleo essencial destas plantas apresenta potencial antibacteriano e antiparasitario .

Castro Urdiales, Dario Vinicio - One of the best experts on this subject based on the ideXlab platform.

  • Composición fitoquímica de los aceites esenciales de Syzygium aromaticum y Citrus Limonia y actividad antimicrobiana frente a Staphylococcus aureus subsp. aureus cepa ATCC 25923
    'Universidad de Cuenca', 2020
    Co-Authors: Castro Garzón, Leonardo Enrique, Castro Urdiales, Dario Vinicio
    Abstract:

    Actualmente la ciencia ha puesto en marcha un auge investigativo a través del regreso en la historia al estudio de especies vegetales con potenciales actividades biológicas, siendo la propiedad antimicrobiana el principal motivo de interés, con el fin de contrarrestar muchos problemas relacionados con microorganismos patógenos en especial aquellos capaces de desarrollar mecanismos de resistencia frente a tratamientos antimicrobianos habituales como Staphylococcus aureus. En este proyecto se llevó a cabo un estudio de tipo exploratorio y cuasi-experimental en donde se determinó la actividad antimicrobiana de los aceites esenciales (AEs) de las especies vegetales Citrus Limonia y Syzygium aromaticum frente a la cepa de Staphylococcus aureus ATCC 25923. Los aceites esenciales fueron obtenidos por arrastre por vapor de agua, consiguiendo un rendimiento del 0.64 % para Citrus Limonia y 1.19 % para Syzygium aromaticum, posteriormente se identificaron los componentes bioactivos principales por cromatografía en capa fina (TLC) en función de sus factores de retención y características colorimétricas, demostrando la presencia de limoneno, citral, geraniol, trans-cariofileno, alfa-pineno, alfa-terpineno y eugenol en el AE de Citrus Limonia y eugenol en Syzygium aromaticum; finalmente se determinó la actividad antimicrobiana de los AEs frente la cepa de Staphylococcus aureus ATCC 25923 mediante el método estandarizado de macrodilución en caldo obteniendo una concentración mínima inhibitoria (CMI) de 0.6 % para el AE de Citrus Limonia y 0.3 % para Syzygium aromaticum; y una concentración mínima bactericida (CMB) mediante la técnica de extensión en agar de 2.5 % y 1.25 % respectivamente.Currently, science has launched a research boom through the return in history to study plant species with potential biological activities, being the main antimicrobial property of interest, in order to counteract many problems related to pathogenic microorganisms, especially those capable of developing resistance mechanisms against usual antimicrobial treatments such as Staphylococcus aureus. In this project an exploratory and quasi-experimental study was conducted in which the antimicrobial activity of the essential oils (AEs) of the plant species Citrus Limonia and Syzygium aromaticum against the Staphylococcus aureus ATCC 25923 bacteria was determined. The oils essential were obtained by steam traction, obtaining a yield of 0.64% for Citrus Limonia and 1.19% for Syzygium aromaticum, subsequently the main bioactive components were identified by TLC based on their retention factors and colorimetric characteristics, demonstrating the presence of Limonene, Citral, Geraniol, Trans-Caryophylene, Alpha-Pinene, Alpha-Terpinen and Eugenol in the Citrus Limon AE and Eugenol in Syzygium aromaticum; finally, the antimicrobial activity of the AEs was determined against the Staphylococcus aureus strain ATCC 25923 by means of the standardized method of macrodilution in broth, obtaining a MIC of 0.6% for the Citrus Limonia AE and 0.3% for Syzygium aromaticum; and a CMB using the agar extension technique of 2.5% and 1.25% respectively.Bioquímico FarmacéuticoCuenc

Dario Vinicio Castro Urdiales - One of the best experts on this subject based on the ideXlab platform.

  • composicion fitoquimica de los aceites esenciales de syzygium aromaticum y Citrus Limonia y actividad antimicrobiana frente a staphylococcus aureus subsp aureus cepa atcc 25923
    2020
    Co-Authors: Leonardo Enrique Castro Garzon, Dario Vinicio Castro Urdiales
    Abstract:

    Actualmente la ciencia ha puesto en marcha un auge investigativo a traves del regreso en la historia al estudio de especies vegetales con potenciales actividades biologicas, siendo la propiedad antimicrobiana el principal motivo de interes, con el fin de contrarrestar muchos problemas relacionados con microorganismos patogenos en especial aquellos capaces de desarrollar mecanismos de resistencia frente a tratamientos antimicrobianos habituales como Staphylococcus aureus. En este proyecto se llevo a cabo un estudio de tipo exploratorio y cuasi-experimental en donde se determino la actividad antimicrobiana de los aceites esenciales (AEs) de las especies vegetales Citrus Limonia y Syzygium aromaticum frente a la cepa de Staphylococcus aureus ATCC 25923. Los aceites esenciales fueron obtenidos por arrastre por vapor de agua, consiguiendo un rendimiento del 0.64 % para Citrus Limonia y 1.19 % para Syzygium aromaticum, posteriormente se identificaron los componentes bioactivos principales por cromatografia en capa fina (TLC) en funcion de sus factores de retencion y caracteristicas colorimetricas, demostrando la presencia de limoneno, citral, geraniol, trans-cariofileno, alfa-pineno, alfa-terpineno y eugenol en el AE de Citrus Limonia y eugenol en Syzygium aromaticum; finalmente se determino la actividad antimicrobiana de los AEs frente la cepa de Staphylococcus aureus ATCC 25923 mediante el metodo estandarizado de macrodilucion en caldo obteniendo una concentracion minima inhibitoria (CMI) de 0.6 % para el AE de Citrus Limonia y 0.3 % para Syzygium aromaticum; y una concentracion minima bactericida (CMB) mediante la tecnica de extension en agar de 2.5 % y 1.25 % respectivamente.

B E Maserti - One of the best experts on this subject based on the ideXlab platform.

  • polyploidization alters constitutive content of volatile organic compounds voc and improves membrane stability under water deficit in volkamer lemon Citrus Limonia osb leaves
    Environmental and Experimental Botany, 2016
    Co-Authors: Dayse Drielly Souza Santana Vieira, François Luro, Raphaël Morillon, Giovanni Emiliani, Marco Michelozzi, Mauro Centritto, Francesco Loreto, Abelmon Da Silva Gesteira, B E Maserti
    Abstract:

    Abstract In Citrus species chromosome doubling naturally occurs in somatic embryos and doubled diploid plants often show better adaptation to adverse environmental condition. To understand the molecular determinants of stress acclimation, we examined the response to water deficit in diploid (2×VL) and doubled diploid (4×VL) seedlings of Volkamer lemon (Citrus Limonia Osb.) assessing the profile of constitutive volatile organic compound (VOC) in control and stressed conditions. Physiological parameters and leaf volatile compound profiles were measured during water deficit and 24 h after rehydration of plants to field capacity. Net photosynthesis and stomatal conductance were reduced in water stressed leaves, with no significant differences between 2×VL and 4×VL plants. Malondialdehyde concentration, a marker of lipid peroxidation of cellular membranes, was significantly more higher in stressed 2×VL leaves than in 4×VL. The blend of constitutive VOC was different in control leaves being oxygenated monoterpenoids more abundant in 2×VL leaves, and monoterpenoids more abundant in 4×VL leaves. Water deficit did not stimulate biosynthesis of terpenoids, whereas accumulation of trans-2 hexenal, a green leaf volatile (GLV) synthesized after membrane denaturation, was observed in stressed leaves of 2×VL leaves, but not in 4×VL leaves. Semiquantitative PCR showed an increase of the expression of HPL, the gene encoding for hydroperoxidase lyase which catalyzes 2-hexenal formation, only in 2×VL plants. The expression of the putative dehydration transcription factor DREB2A was also observed only in 2×VL water stressed plants. This work shows that level of ploidy may alter constitutive content of GLV by Citrus, therefore likely affecting plants capacity of protection and interaction with other organisms. Whereas diploid and double diploid plants showed similar physiological responses to water deficit, a biochemical marker indicated that membranes of double diploid leaves were more resistant to the stress. These results provide intriguing insights into the regulation of terpenoids and oxylipins pathways as a function of polyploidization in a non-model plant species.