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1.
Braz. J. Pharm. Sci. (Online) ; 58: e18672, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1360164

RESUMO

The use of plants in disease treatment is cost effective and relatively safe. This study was designed to investigate anti-hyperlipidemic and anti-diabetic activity of ethanolic leaf extract of Catharanthus roseus alone and in combination therapy in hyperlipidemic & diabetic mice. Eight groups comprising five mice each were used. Group A was hyperlipidemic control, group B, C, D received atorvastatin (20 mg/kg), leaf extract (200 mg/kg) and leaf extract in combination with atorvastatin (200 mg/kg and 20 mg/kg) orally for 15 days. Group E was diabetic control. Group F, G, H received sitagliptin (40 mg/kg), leaf extract (200 mg/kg) and extract in combination with sitagliptin (200 mg/kg and 40 mg/kg) orally for 7 days. Blood cholesterol levels were measured at 1st, 5th, 10th and 15th day and fasting blood sugar levels were measured at 2, 12, 24, 72 and 168 hours during treatment. One-way ANOVA with tukey- kramer multiple comparison test was used. The chemical characterization of ethanolic extract of Catharanthus roseus leaves showed presence of alkaloids, saponins, tannins and flavonoids. Ethanolic extract of Catharanthus roseus has significant anti-hyperlipidemic & anti-diabetic effects (p<0.05, p<0.01) when compared with control but had not cause significantly increase in anti-hyperlipidemic effects of atorvastatin. While significantly increased the antidiabetic effect of sitagliptin (p<0.05)


Assuntos
Folhas de Planta/classificação , Catharanthus/efeitos adversos , Hipoglicemiantes , Glicemia , Colesterol/sangue , Doença/classificação , Alcaloides/sangue , Hiperlipidemias/sangue
2.
Appl Environ Microbiol ; 86(17)2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32591387

RESUMO

Escherichia coli and Saccharomyces cerevisiae have been used extensively for heterologous production of a variety of secondary metabolites. Neither has an endogenous high-flux isoprenoid pathway, required for the production of terpenoids. Azospirillum brasilense, a nonphotosynthetic GRAS (generally recognized as safe) bacterium, produces carotenoids in the presence of light. The carotenoid production increases multifold upon inactivating a gene encoding an anti-sigma factor (ChrR1). We used this A. brasilense mutant (Car-1) as a host for the heterologous production of two high-value phytochemicals, geraniol and amorphadiene. Cloned genes (crtE1 and crtE2) of A. brasilense encoding native geranylgeranyl pyrophosphate synthases (GGPPS), when overexpressed and purified, did not produce geranyl pyrophosphate (GPP) in vitro Therefore, we cloned codon-optimized copies of the Catharanthus roseus genes encoding GPP synthase (GPPS) and geraniol synthase (GES) to show the endogenous intermediates of the carotenoid biosynthetic pathway in the Car-1 strain were utilized for the heterologous production of geraniol in A. brasilense Similarly, cloning and expression of a codon-optimized copy of the amorphadiene synthase (ads) gene from Artemisia annua also led to the heterologous production of amorphadiene in Car-1. Geraniol or amorphadiene content was estimated using gas chromatography-mass spectrometry (GC-MS) and GC. These results demonstrate that Car-1 is a promising host for metabolic engineering, as the naturally available endogenous pool of the intermediates of the carotenoid biosynthetic pathway of A. brasilense can be effectively utilized for the heterologous production of high-value phytochemicals.IMPORTANCE To date, the major host organisms used for the heterologous production of terpenoids, i.e., E. coli and S. cerevisiae, do not have high-flux isoprenoid pathways and involve tedious metabolic engineering to increase the precursor pool. Since carotenoid-producing bacteria carry endogenous high-flux isoprenoid pathways, we used a carotenoid-producing mutant of A. brasilense as a host to show its suitability for the heterologous production of geraniol and amorphadiene as a proof-of-concept. The advantages of using A. brasilense as a model system include (i) dispensability of carotenoids and (ii) the possibility of overproducing carotenoids through a single mutation to exploit high carbon flux for terpenoid production.


Assuntos
Monoterpenos Acíclicos/metabolismo , Artemisia annua/genética , Azospirillum brasilense/genética , Catharanthus/genética , Engenharia Metabólica , Sesquiterpenos Policíclicos/metabolismo , Azospirillum brasilense/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Plantas/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-31642365

RESUMO

This work evaluated the potential of Catharanthus roseus in phytoremediation of As, Ba, Cd, Cu, Cr, Ni, Pb, Se and Zn in sewage sludge-based substrates. C. roseus was cultivated for 108 days in a treatment containing sewage sludge:vermiculite (70:30%) and in the control with 100% commercial substrate. The plants cultivated in sludge showed approximately four times greater height, number of leaves and stem diameter, as well as 89% higher fresh mass than those of the control. The highest concentrations of the metals were obtained in the roots of plants grown in the sludge, and ranged from 2.04 (Cd) to 1121 mg kg-1 (Zn). Cu, Cd and Zn had a higher bioconcentration factor than 1 in both treatments. On the other hand, the translocation factor value in the control was greater than 1 for Ba, Cd, Cu, Ni, Se and Zn. The results showed that C. roseus was efficient in the phytoremediation of the evaluated metals, in which the translocation process was progressive in the treatment that presented higher metal content.


Assuntos
Catharanthus/metabolismo , Metais Pesados/metabolismo , Eliminação de Resíduos/métodos , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Catharanthus/crescimento & desenvolvimento , Metais Pesados/análise , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Esgotos/química , Poluentes do Solo/análise
4.
Bioprocess Biosyst Eng ; 43(4): 747-752, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31758239

RESUMO

Plant suspension culture is attracting interest as a promising platform to produce biological medicines due to the absence of virus, prions or DNA related to mammals during the production process. However, the heterogenic plant cell proliferation nature is particularly challenging for establishing industrial processes based on innovative approaches currently used, particularly in the animal cell culture industry. In this context, while Process Analytical Technology (PAT) tools have been used to monitor classical parameters such as biomass dry weight, its use in cells heterogeneity has received limited attention. Therefore, the feasibility of in situ monitoring of cell differentiation in plant cell suspensions employing NIR spectroscopy and chemometrics was investigated. Off-line measurements of cell heterogeneity in term of cell differentiation and in-line NIR spectra captured in 3 L bioreactor cultures were employed to generate calibration models. Then models were tested to estimate the population distribution of parenchyma, collenchyma and sclerenchyma cells during Catharanthus roseus suspension cultures. Results have proven in situ NIR spectroscopy as a capable PAT tool to monitor differentiated cells accurately and in real-time. These results are the starting point to follow-up PAT systems so that plant cell culture heterogeneity may be better understood and controlled in biopharmaceutical plant cell cultures.


Assuntos
Reatores Biológicos , Catharanthus , Diferenciação Celular , Células Vegetais/metabolismo , Catharanthus/citologia , Catharanthus/metabolismo
5.
Mol Plant ; 11(5): 645-658, 2018 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-29530817

RESUMO

Extensins (EXTs) are highly repetitive plant O-glycoproteins that require several post-translational modifications (PTMs) to become functional in plant cell walls. First, they are hydroxylated on contiguous proline residues; then they are O-glycosylated on hydroxyproline and serine. After secretion into the apoplast, O-glycosylated EXTs form a tridimensional network organized by inter- and intra-Tyr linkages. Recent studies have made significant progress in the identification of the enzymatic machinery required to process EXTs, which includes prolyl 4-hydroxylases, glycosyltransferases, papain-type cysteine endopeptidases, and peroxidases. EXTs are abundant in plant tissues and are particularly important in rapidly expanding root hairs and pollen tubes, which grow in a polar manner. Small changes in EXT PTMs affect fast-growing cells, although the molecular mechanisms underlying this regulation are unknown. In this review, we highlight recent advances in our understanding of EXT modifications throughout the secretory pathway, EXT assembly in cell walls, and possible sensing mechanisms involving the Catharanthus roseus cell surface sensor receptor-like kinases located at the interface between the apoplast and the cytoplasmic side of the plasma membrane.


Assuntos
Catharanthus/metabolismo , Glicoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Membrana Celular/metabolismo , Processamento de Proteína Pós-Traducional
6.
Biotechnol Prog ; 33(1): 66-69, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27813337

RESUMO

Hairy root cultures generated using Agrobacterium rhizogenes are an extensively investigated system for the overproduction of various secondary metabolite based pharmaceuticals and chemicals. This study demonstrated a transgenic Catharanthus roseus hairy root line carrying a feedback-insensitive anthranilate synthase (AS) maintained chemical and genetic stability for 11 years. The AS gene was originally inserted in the hairy root genome under the control of a glucocorticoid inducible promoter. After 11 years continuous maintenance of this hairy root line, genomic PCR of the ASA gene showed the presence of ASA gene in the genome. The mRNA level of AS was induced to 52-fold after feeding the inducer as compared to the uninduced control. The AS enzyme activity was 18.4 nmol/(min*mg) in the induced roots as compared to 2.1 nmol/(min*mg) in the control. In addition, the changes in terpenoid indole alkaloid concentrations after overexpressing AS were tracked over 11 years. The major alkaloid levels in induced and control roots at 11 years are comparable with the metabolite levels at 5 years. This study demonstrates the long term genetic and biochemical stability of hairy root lines, which has important implications for industrial scale applications. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:66-69, 2017.


Assuntos
Antranilato Sintase/biossíntese , Catharanthus/citologia , Técnicas de Cultura de Células , Raízes de Plantas/citologia , Agrobacterium/genética , Antranilato Sintase/genética , Catharanthus/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Células Vegetais/metabolismo , Raízes de Plantas/genética , Plantas Geneticamente Modificadas
7.
Int J Syst Evol Microbiol ; 66(9): 3463-3467, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27266266

RESUMO

Mexican periwinkle virescence (MPV) phytoplasma was originally discovered in diseased plants of Madagascar periwinkle (Catharanthus roseus) in Yucatán, Mexico. On the basis of results from RFLP analysis of PCR-amplified 16S rRNA gene sequences, strain MPV was previously classified as the first known member of phytoplasma group 16SrXIII, and a new subgroup (16SrXIII-A) was established to accommodate MPV phytoplasma. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain MPV represents a lineage distinct from previously described 'CandidatusPhytoplasma' species. Nucleotide sequence alignments revealed that strain MPV shared less than 97.5 % 16S rRNA gene sequence similarity with all previously described 'Ca.Phytoplasma' species. Based on unique properties of the DNA, we propose recognition of Mexican periwinkle virescence phytoplasma strain MPV as representative of a novel taxon, 'CandidatusPhytoplasma hispanicum'.


Assuntos
Catharanthus/microbiologia , Filogenia , Phytoplasma/classificação , Doenças das Plantas/microbiologia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , México , Phytoplasma/genética , Phytoplasma/isolamento & purificação , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Arch Microbiol ; 195(7): 483-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23695435

RESUMO

This study reports the introduction of gfp marker in two endophytic bacterial strains (Pantoea agglomerans C33.1, isolated from cocoa, and Enterobacter cloacae PR2/7, isolated from citrus) to monitor the colonization in Madagascar perinwinkle (Catharanthus roseus). Stability of the plasmid encoding gfp was confirmed in vitro for at least 72 h of bacterial growth and after the colonization of tissues, under non-selective conditions. The colonization was observed using fluorescence microscopy and enumeration of culturable endophytes in inoculated perinwinkle plants that grew for 10 and 20 days. Gfp-expressing strains were re-isolated from the inner tissues of surface-sterilized roots and stems of inoculated plants, and the survival of the P. agglomerans C33:1gfp in plants 20 days after inoculation, even in the absence of selective pressure, suggests that is good colonizer. These results indicated that both gfp-tagged strains, especially P. agglomerans C33.1, may be useful tools to deliver enzymes or other proteins in plant.


Assuntos
Catharanthus/microbiologia , Endófitos/crescimento & desenvolvimento , Enterobacter cloacae/crescimento & desenvolvimento , Proteínas de Fluorescência Verde/genética , Pantoea/crescimento & desenvolvimento , Endófitos/genética , Endófitos/isolamento & purificação , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Proteínas de Fluorescência Verde/metabolismo , Microscopia de Fluorescência , Pantoea/genética , Pantoea/isolamento & purificação , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Plasmídeos , Transformação Bacteriana
9.
World J Microbiol Biotechnol ; 28(4): 1475-81, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22805929

RESUMO

Based on the premise of symbiotic control, we genetically modified the citrus endophytic bacterium Methylobacterium extorquens, strain AR1.6/2, and evaluated its capacity to colonize a model plant and its interaction with Xylella fastidiosa, the causative agent of Citrus Variegated Chlorosis (CVC). AR1.6/2 was genetically transformed to express heterologous GFP (Green Fluorescent Protein) and an endoglucanase A (EglA), generating the strains ARGFP and AREglA, respectively. By fluorescence microscopy, it was shown that ARGFP was able to colonize xylem vessels of the Catharanthus roseus seedlings. Using scanning electron microscopy, it was observed that AREglA and X. fastidiosa may co-inhabit the C. roseus vessels. M. extorquens was observed in the xylem with the phytopathogen X. fastidiosa, and appeared to cause a decrease in biofilm formation. AREglA stimulated the production of resistance protein, catalase, in the inoculated plants. This paper reports the successful transformation of AR1.6/2 to generate two different strains with a different gene each, and also indicates that AREglA and X. fastidiosa could interact inside the host plant, suggesting a possible strategy for the symbiotic control of CVC disease. Our results provide an enhanced understanding of the M. extorquens-X. fastidiosa interaction, suggesting the application of AR1.6/2 as an agent of symbiotic control.


Assuntos
Catharanthus/microbiologia , Celulase/biossíntese , Endófitos/enzimologia , Methylobacterium extorquens/enzimologia , Plântula/microbiologia , Xylella/crescimento & desenvolvimento , Antibiose , Celulase/genética , Endófitos/genética , Engenharia Metabólica , Methylobacterium extorquens/genética , Microscopia Eletrônica de Varredura , Doenças das Plantas/prevenção & controle , Xilema/microbiologia
10.
Bol. latinoam. Caribe plantas med. aromát ; 11(2): 163-171, mar. 2012. tab
Artigo em Espanhol | LILACS | ID: lil-647628

RESUMO

With the main objective of evaluate the principals agronomic parameters of soil and organic substrate, as well as nutritional indicators and biomass of medicinal plants used to control for diabetes mellitus: Catharanthus roseus (L.) G. Don, Momordica charantia L. and Azadirachta indica A. Juss, this research was conducted during 2010 and 2011 at El Colegio de la Frontera Sur (ECOSUR). The growth of potted plants was evaluated in nursery phase, analysis of soil, plants and organic substrate were performed according to NOM 021-RECNAT-2000, which allowed to identify significant differences between crop plants and substrates used. The use of organic matter in the soil improved the nutrition indicators in more than 50 percent as well as the biomass increased.


Con el objetivo de evaluar los principales parámetros agronómicos de suelo y sustrato orgánico, así como indicadores nutricionales y biomasa de las plantas medicinales utilizadas para el control de la diabetes mellitus: Catharanthus roseus (L.) G. Don, Momordica charantia L. y Azadirachta indica A. Juss, se realizó esta investigación durante 2010 y 2011 en El Colegio de la Frontera Sur (ECOSUR). El crecimiento de las plantas fue en macetas evaluándose en fase vivero, los análisis de suelo, sustrato orgánico y plantas se realizaron de acuerdo a NOM 021-RECNAT-2000; lo que permitió identificar diferencias significativas entre cultivos de plantas y sustratos utilizados. El uso de materia orgánica en el sustrato mejoró los indicadores nutricionales de los cultivos en más de un 50 por ciento al igual que la biomasa se incrementó.


Assuntos
Azadirachta/crescimento & desenvolvimento , Catharanthus/crescimento & desenvolvimento , Momordica charantia/crescimento & desenvolvimento , Produção Agrícola , Biomassa , Germinação , México , Agricultura Orgânica , Substratos para Tratamento Biológico , Fatores de Tempo
11.
Biotechnol Lett ; 32(7): 997-1003, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20349334

RESUMO

A Morinda citrifolia cell line was obtained by overexpresion of 1-deoxy-D: -xylulose 5-phosphate synthase (DXS) from Catharanthus roseus, a key enzyme of the metabolic pathway of anthraquinones (AQs). This cell line increased AQs production by about 24% compared to the control cell line. This transgenic cell line which carries dxs cDNA isolated from Catharanthus roseus, was achieved by direct transformation of cell suspension cultures of M. citrifolia using a hypervirulent Agrobacterium tumefaciens strain. The effects of the overexpression of the dxs gene also resulted in increased levels of dxs mRNA transcripts and DXS activity compared to the control cell line. In addition, total phenolics and phenylalanine ammonia-lyase activity were evaluated and were significantly higher in the transgenic line than in controls.


Assuntos
Antraquinonas/metabolismo , Catharanthus/enzimologia , Expressão Gênica , Morinda/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Transferases/metabolismo , Agrobacterium tumefaciens/genética , Catharanthus/genética , Perfilação da Expressão Gênica , Vetores Genéticos , Morinda/química , Morinda/genética , Fenóis/análise , Fenilalanina Amônia-Liase/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , RNA Mensageiro/análise , RNA de Plantas/análise , Transferases/genética
12.
J Microbiol ; 47(4): 448-54, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19763419

RESUMO

Methylobacterium mesophilicum, originally isolated as an endophytic bacterium from citrus plants, was genetically transformed to express green fluorescent protein (GFP). The GFP-labeled strain of M. mesophilicum was inoculated into Catharanthus roseus (model plant) seedlings and further observed colonizing its xylem vessels. The transmission of this endophyte by Bucephalogonia xanthophis, one of the insect vectors that transmit Xylella fastidiosa subsp. pauca, was verified by insects feeding from fluids containing the GFP bacterium followed by transmission to plants and isolating the endophyte from C. roseus plants. Forty-five days after inoculation, the plants exhibited endophytic colonization by M. mesophilicum, confirming this bacterium as a nonpathogenic, xylem-associated endophyte. Our data demonstrate that M. mesophilicum not only occupy the same niche of X. fastidiosa subsp. pauca inside plants but also may be transmitted by B. xanthophis. The transmission, colonization, and genetic manipulation of M. mesophilicum is a prerequisite to examining the potential use of symbiotic control to interrupt the transmission of X. fastidiosa subsp. pauca, the bacterial pathogen causing Citrus variegated chlorosis by insect vectors.


Assuntos
Citrus/microbiologia , Hemípteros/microbiologia , Insetos Vetores/microbiologia , Methylobacterium/fisiologia , Controle Biológico de Vetores/métodos , Doenças das Plantas/microbiologia , Xylella/fisiologia , Animais , Antibiose , Catharanthus/microbiologia , Hemípteros/fisiologia , Insetos Vetores/fisiologia , Methylobacterium/crescimento & desenvolvimento , Methylobacterium/isolamento & purificação , Xilema/microbiologia
13.
Biotechnol Lett ; 31(4): 591-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19030782

RESUMO

The effects of methyl jasmonate, salicylic acid and ethylene on alkaloid accumulation in in vitro cell suspension, hairy roots and rootless shoot cultures of Catharanthus roseus were analyzed. Ajmalicine, but not catharanthine, accumulation was promoted by jasmonate and ethylene treatments in cell suspensions. In hairy roots, jasmonate induced the accumulation of both alkaloids, whereas ethylene only induced catharanthine accumulation. In shoot cultures, positive effects of jasmonate and ethylene were recorded only in vindoline accumulation. Ethylene diminished catharanthine accumulation in these cultures. No effect of salicylic acid was observed in any of the studied in vitro culture systems.


Assuntos
Acetatos/metabolismo , Catharanthus/efeitos dos fármacos , Catharanthus/metabolismo , Ciclopentanos/metabolismo , Etilenos/metabolismo , Oxilipinas/metabolismo , Ácido Salicílico/metabolismo , Alcaloides de Triptamina e Secologanina/metabolismo , Alcaloides de Vinca/metabolismo , Células Cultivadas , Raízes de Plantas/química , Brotos de Planta/química
14.
Mol Biotechnol ; 41(3): 278-85, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18841500

RESUMO

The induction of several secondary metabolites in plants is one of the most commonly observed effects after the external addition of methyl jasmonate (MeJA). After the elicitation of Catharanthus roseus hairy roots with different concentrations of MeJA, changes in the accumulation of alkaloids such as ajmalicine, serpentine, ajmaline and catharanthine were observed. In addition to the increased accumulation of alkaloids in the tissues, the root exudation of phytochemicals increased compared to that of the non-treated control hairy roots. Moreover, MeJA induced differential secretion of several C. roseus hairy root metabolites.


Assuntos
Acetatos/farmacologia , Catharanthus/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oxilipinas/farmacologia , Raízes de Plantas/metabolismo , Alcaloides de Triptamina e Secologanina/análise , Análise de Variância , Catharanthus/genética , Cromatografia Líquida de Alta Pressão , Exsudatos de Plantas/análise , Exsudatos de Plantas/metabolismo , Raízes de Plantas/química , Alcaloides de Triptamina e Secologanina/metabolismo
15.
J Microbiol ; 45(5): 388-93, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17978797

RESUMO

Citrus variegated chlorosis (CVC) is a disease of the sweet orange [Citrus sinensis (L.)], which is caused by Xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that has been shown to infect all sweet orange cultivars. Sweet orange trees have been occasionally observed to be infected by Xylella fastidiosa without evidencing severe disease symptoms, whereas other trees in the same grove may exhibit severe disease symptoms. The principal endophytic bacterial species isolated from such CVC-asymptomatic citrus plants is Curtobacterium flaccumfaciens. The Madagascar periwinkle [Citrus sinensis (L.)] is a model plant which has been used to study X. fastidiosa in greenhouse environments. In order to characterize the interactions of X. fastidiosa and C. flaccumfaciens, periwinkle plants were inoculated separately with C. flaccumfaciens, X. fastidiosa, and both bacteria together. The number of flowers produced by the plants, the heights of the plants, and the exhibited disease symptoms were evaluated. PCR-primers for C. flaccumfaciens were designed in order to verify the presence of this endophytic bacterium in plant tissue, and to complement an existing assay for X. fastidiosa. These primers were capable of detecting C. flaccumfaciens in the periwinkle in the presence of X. fastidiosa. X. fastidiosa induced stunting and reduced the number of flowers produced by the periwinkle. When C. flaccumfaciens was inoculated together with X. fastidiosa, no stunting was observed. The number of flowers produced by our doubly- inoculated plants was an intermediate between the number produced by the plants inoculated with either of the bacteria separately. Our data indicate that C. flaccumfaciens interacted with X. fastidiosa in C. roseus, and reduced the severity of the disease symptoms induced by X. fastidiosa. Periwinkle is considered to be an excellent experimental system by which the interaction of C. flaccumfaciens and other endophytic bacteria with X. fastidiosa can be studied.


Assuntos
Catharanthus/microbiologia , Micrococcaceae/fisiologia , Xylella/patogenicidade , Primers do DNA , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Xylella/genética , Xylella/isolamento & purificação
16.
Fitoterapia ; 78(7-8): 540-4, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17683880

RESUMO

Rats treated with 100 mg /kg/day of the Catharanthus roseus ethanol extract had high rate of wound contraction significantly decreased epithelization period, significant increase in dry weight and hydroxyproline content of the granulation tissue when compared with the controls. Wound contraction together with increased tensile strength and hydroxyproline content support the use of C. roseus in the management of wound healing.


Assuntos
Catharanthus , Fitoterapia , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Tecido de Granulação/efeitos dos fármacos , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Folhas de Planta , Ratos , Ratos Sprague-Dawley , Ferimentos Penetrantes/tratamento farmacológico
17.
Plant Physiol Biochem ; 45(6-7): 501-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17544287

RESUMO

Catharanthus roseus transformed roots were cultured in the presence of salicylic acid (SA) at concentrations between 0.1 fM and 100 pM and the effect on root growth was evaluated. Significant morphological changes in the lateral roots were recorded on day two in the SA treatment. Presence of SA increased root cap size and caused the appearance of lateral roots closer to the root tip. The bioassay was sensitive enough to allow testing of low concentrations of other growth regulators that may affect root morphology and physiology.


Assuntos
Catharanthus/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Ácido Salicílico/farmacologia , Catharanthus/efeitos dos fármacos , Relação Dose-Resposta a Droga , Cinética , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/efeitos dos fármacos
18.
J Microbiol ; 45(1): 11-4, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17342049

RESUMO

Over the last few years, the endophytic bacterial community associated with citrus has been studied as an important component interacting with Xylella fastidiosa, the causal agent of citrus variegated chlorosis (CVC). This bacterium may also colonize some model plants, such as Catharanthus roseus and Nicotiana clevelandii. In the present study, we compared the endophytic colonization of Citrus sinensis and Catharanthus roseus using the endophytic bacteria Klebsiella pneumoniae. We chose an appropriate strain, K. pneumoniae 342 (Kp342), labeled with the GFP gene. This strain was inoculated onto seedlings of C. sinensis and C. roseus. The isolation frequency was determined one week after the inoculation and the endophytic colonization of K. pneumoniae was observed using fluorescence microscopy. Although the endophytic bacterium was more frequently isolated from C. roseus than from C. sinensis, the colonization profiles for both host plants were similar, suggesting that C. roseus could be used as a model plant to study the interaction between endophytic bacteria and X. fastidiosa.


Assuntos
Catharanthus/microbiologia , Citrus sinensis/microbiologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Proteínas de Fluorescência Verde/genética , Klebsiella pneumoniae/isolamento & purificação , Plântula/microbiologia
19.
Can J Microbiol ; 52(5): 419-26, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16699566

RESUMO

Over the last few years, endophytic bacterial communities associated with citrus have been studied as key components interacting with Xylella fastidiosa. In this study, we investigated the possible interaction between the citrus endophyte Methylobacterium mesophilicum SR1.6/6 and X. fastidiosa in model plants such as Catharanthus roseus (Madagaskar periwinkle) and Nicotiana clevelandii (Clevelands tobacco). The aim of this study was to establish the fate of M. mesophilicum SR1.6/6 after inoculation of C. roseus and N. clevelandii plants, using PCR-DGGE (polymerase chain reaction--denaturing gradient gel electrophoresis) and plating techniques. Shifts in the indigenous endophytic bacterial communities were observed in plants inoculated with strain SR1.6/6, using specific primers targeting alpha- and beta-Proteobacteria. Cells of strain SR1.6/6 were observed in a biofilm structure on the root and hypocotyl surfaces of in vitro seedlings inoculated with M. mesophilicum SR1.6/6. This emphasizes the importance of these tissues as main points of entrance for this organism. The results showed that C. roseus and N. clevelandii could be used as model plants to study the interaction between M. mesophilicum and X. fastidiosa.


Assuntos
Methylobacterium/fisiologia , Agricultura/métodos , Biofilmes/crescimento & desenvolvimento , Catharanthus/microbiologia , Citrus/microbiologia , Primers do DNA , Methylobacterium/genética , Methylobacterium/isolamento & purificação , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Reação em Cadeia da Polimerase , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Plântula/microbiologia , Nicotiana/microbiologia , Xylella/fisiologia
20.
J Biosci Bioeng ; 101(4): 287-96, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16716935

RESUMO

Monoterpene indole alkaloids (MIAs) are a large class of plant alkaloids with significant pharmacological interest. The sustained production of MIAs at high yields is an important goal in biotechnology. Intensive effort has been expended toward the isolation, cloning, characterization and transgenic modulation of genes involved in MIA biosynthesis and in the control of the expression of these biosynthesis-related genes. At the same time, considerable progress has been made in the detailed description of the subcellular-, cellular-, tissue- and organ-specific expressions of portions of the biosynthetic pathways leading to the production of MIAs, revealing a complex picture of the transport of biosynthetic intermediates among membrane compartments, cells and tissues. The identification of the particular environmental and ontogenetic requirements for maximum alkaloid yield in MIA-producing plants has been useful in improving the supply of bioactive molecules. The search for new bioactive MIAs, particularly in tropical and subtropical regions, is continuously increasing the arsenal for therapeutic, industrially and agriculturally useful molecules. In this review we focus on recent progress in the production of MIAs in transgenic cell cultures and organs (with emphasis on Catharanthus roseus and Rauvolfia serpentina alkaloids), advances in the understanding of in planta spatial-temporal expression of MIA metabolic pathways, and on the identification of factors capable of modulating bioactive alkaloid accumulation in nontransgenic differentiated cultures and plants (with emphasis on new MIAs from Psychotria species). The combined use of metabolic engineering and physiological modulation in transgenic and wild-type plants, although not fully exploited to date, is likely to provide the sustainable and rational supply of bioactive MIAs needed for human well being.


Assuntos
Biotecnologia/métodos , Técnicas de Cultura de Células/métodos , Alcaloides Indólicos/química , Monoterpenos/química , Catharanthus/metabolismo , Modelos Genéticos , Extratos Vegetais/metabolismo , Fenômenos Fisiológicos Vegetais , Psychotria/metabolismo , Rauwolfia/metabolismo
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