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biotransformation of valdecoxib by plant cell cultures.valdecoxib is a new anti-inflammatory drug that is highly selective for inhibition of the inducible form of cyclooxygenase (cox-2). in the present study, biotransformation of valdecoxib was investigated in cell cultures of five medicinal plants, viz., catharanthus roseus, azadirachta indica, capsicum annuum, ervatamia heyneana, and nicotiana tabacum. identification of the biotransformed products was carried out by using high-performance liquid chromatography coupled with diode array detection an ...200818556810
bioreactor considerations for secondary metabolite production from plant cell tissue culture: indole alkaloids from catharanthus roseus.batch shake flask studies with catharanthus roseus demonstrated that alkaloid production commenced only after growth had slowed or ceased. to obtain high alkaloid productivities for extended periods, a hormone-free production medium was used. to develop a readily scalable process, both immobilized and suspended cell systems were studied. in the immobilized cell systems, growth, glucose utilization, and alkaloid production were suppressed; for the case of membrane entrapped cells this suppression ...198818584698
vindoline formation in shoot cultures of catharanthus roseus is synchronously activated with morphogenesis through the last biosynthetic step.the madagascar periwinkle (catharanthus roseus) produces the monoterpenoid alkaloid vindoline, which requires a specialized cell organization present only in the aerial tissues. vindoline content can be affected by photoperiod and this effect seems to be associated with the morphogenetic capacity of branches; this association formed the basis of the study reported here.200818587132
diffusion of sucrose and yohimbine in calcium alginate gel beads with or without entrapped plant cells.the diffusion characteristics of sucrose, a nutrient, and yohimbine, a secondary metabolite, in alginate gel beads, with or without entrapped periwinkle (catharanthus roseus) or apple (malus domestica) cells, were investigated. effective diffusivities of both solutes in the gel beads were determined by two different methods from transient concentration changes in well-stirred solutions where the beads were suspended. the linear plot method developed in this work is easy to use and requires no da ...198818587800
adhesion of catharanthus roseus cells to surfaces: effect of substrate hydrophobicity. 198818587809
how suspension cultures of catharanthus roseus respond to oxygen limitation: small-scale tests with applications to large-scale cultures.the effect of oxygen supply on the growth of suspension cultures of catharanthus roseus in erlenmeyer flasks was investigated. below a critical oxygen supply rate the culture could not survive. by increasing the oxygen supply, a point is reached where the culture survives but no growth is possible. at higher oxygen supply rates there is a regime where both growth rate and the maximum biomass concentration increase with oxygen supply. eventually there comes a point where no further increase in bi ...198918588199
antidiabetic screening and scoring of 11 plants traditionally used in south africa.to investigate the traditional antidiabetic uses of indigenous or naturalised south african plants using an optimised screening and scoring method.200818588966
development of a strategy to control the dissolved concentrations of oxygen and carbon dioxide at constant shear in a plant cell bioreactor.to examine the effects of volatile components on plant cell growth, a bioreactor control system was developed to simultaneously control the dissolved concentrations of both oxygen and carbon dioxide. the first step in this work was to develop a mathematical model to account for gas-liquid mass transfer; biological utilization and production of o(2) and co(2); and the series of chemical reactions of co(2) in water. using this model and dynamic measurements for dissolved o(2) and co(2), it was obs ...199018592487
optimal temperature control for a structured model of plant cell culture.this article calculates optimal open-loop temperature trajectories that maximize the average rate of product synthesis of a plant cell culture. it uses a previously published five-state mathematical model which describes the growth and product synthesis of a batch plant cell suspension culture of catharanthus roseus under temperature control. the optimal open-loop temperatures maximize the final product concentration for predefined fermentation periods. a single switch in temperature is shown by ...199018592517
production of indole alkaloids by surface immobilized c. roseus cells.a technique was developed to surface immobilize plant cells and was scaled up in laboratory size bioreactors. this technique was shown not to hinder the biosynthetic potential of catharanthus roseus immobilized cells and to induce a partial release (300 microg/l) of serpentine into the culture medium contrary to suspension cultured cells. the release pattern seemed to follow the biosynthesis trends of the product. this release mechanism could be stimulated by a factor of 10 within 2 h by increas ...199018592562
development of bioreactors for the culture of surface immobilized plant cells.the scaleup of the technique of plant cell surface immobilization was performed successfully in specifically designed laboratory size bioreactors. the immobilizing matrix was formed into a vertically wound spiral providing for a high immobilizing area-to-volume ratio (0.8-1.2 cm(-1)). a modified airlift and a mechanically stirred vessel delivered a best bioreactor performance characterized by low biomass frothing and highly efficient plant cell attachment and retention (>or=96%). the growth of c ...199018592566
an investigation into the role of initial k(l)a on the growth and alkaloid accumulation by cultures of catharanthus roseus.the effect of initial k(l)a on the batch culture of catharanthus roseus id1 in a 12.5-l bioreactor has been examined. optimum k(l)a values were found for both growth and alkaloid accumulation. different sparger designs were used to alter the k(l)a values. high k(l)a values caused increased aggregation of the cultures, depressed biomass yields, and altered patterns of alkaloid accumulation.199118597378
studies on the optimization of growth and indole alkaloid production by hairy root cultures of catharanthus roseus.catharanthus roseus hairy root cultures, genetically transformed with agrobacterium rhizogenes, produce a wide variety of indole alkaloids. the effect of sucrose, phosphate, nitrate, and ammonia concentrations on growth and indole alkaloid production of c. roseus hairy root cultures were studied by using statistical experimental designs and linear regression analysis. contradictory effects of these nutrients on growth and indole alkaloid production were found. the maximal growth was obtained by ...199118600658
development of a helical-ribbon impeller bioreactor for high-density plant cell suspension culture.a double helical-ribbon impeller (hri) bioreactor with a 11-l working volume was developed to grow high-density catharanthus roseus cell suspensions. the rheological behavior of this suspension was found to be shear-thinning for concentrations higher than 12 to 15 g dw . l(-1). a granulated agar suspension of similar rheological properties was used as a model fluid for these suspensions. mixing studies revealed that surface baffling and bottom profiling of the bioreactor and impeller speeds of 6 ...199218600977
kinetics and stoichiometry of growth of plant cell cultures of catharanthus roseus and nicotiana tabacum in batch and continuous fermentors.plant cell suspension cultures of catharanthus roseus and nicotiana tabacum were grown in stirred tank bioreactors operated in batch and continuous mode. the stoichiometry of growth of both species in steady-state glucose limited chemostats was studied at a range of different dilution rates. a linear relation was applied to describe specific glucose uptake, oxygen consumption, and carbon dioxide production as a function of the growth rate. specific respiration deviated greatly from the linear re ...199218601193
growth and stoichiometry of a catharanthus roseus cell suspension culture grown under nitrogen-limiting conditions.the uptake of carbohydrate and nitrate by catharanthus roseus cell suspension cultures was studied in relation to biomass production in shake flasks. biomass production was similar when using either 6, 12, 18, or 24 mm nitrate as the nitrogen source and 20 g l(-1) sucrose as the carbon source. in all cases, maximum biomass production was reached when carbohydrates were entirely consumer by the cells. apparent biomass yields, y(x/s) and y(x/n) were 0.49 g biomass g(-1) glucose equivalent and 0.23 ...199118604877
scaleup of ajmalicine production by plant cell cultures of catharanthus roseus.the effect of scaleup on he production of ajmalicine by a catharanthus roseus cell suspension culture in a selected induction medium were studied. in preliminary experiments it was observed that the culture turned brown and the production was inhibited upon transfer from a shake flask to a stirred bioreactor with forced aeration. two factors were recognized as the potential origin of the differences between shake flask and bioreactor cultures: gas composition and mechanical shear forces. these f ...199318609545
production of indole alkaloids by selected hairy root lines of catharanthus roseus.hairy root cultures of catharanthus roseus were established by infection of seedlings with agrobacterium rhizogenes 15834. approximately 150 transformants from four different. c. roseus cultivars were screened for desirable traits in growth and indole alkaloid production. five hairy root clones grew well in liquid culture with doubling times similar to those reported for cell suspensions. fast growing clones had similar morphologies, characterized by thin, straight, and regular branches with thi ...199318609590
a structured model describing carbon and phosphate limited growth of catharanthus roseus plant cell suspensions in batch and chemostat culture.the growth of plant cell suspension cultures of catharanthus roseus in batch fermentors was studied at different initial phosphate levels of the medium. on the basis of the observations and existing knowledge with respect to phosphate metabolism in cultured c. roseus cells, a structured mathematical model was developed for the description of the kinetics of growth and intracellular accumulation of glucose and phosphate, as a function of glucose and phosphate supply. it was shown that the model o ...199318609621
effects of oxygen and nutrients limitation on ajmalicine production and related enzyme activities in high density cultures of catharanthus roseus.oxygen and nutrient limitation was investigated in order to identify the origin of a lower specific ajmalicine production in catharanthus roseus cultures at high cell densities in an induction medium. the effect of oxygen limitation was explored by comparing two identically aerated and agitated high cell density bioreactor cultures with dissolved oxygen (do) concentration of 15% and 85% of air saturation, with respect to alkaloid formation and related enzymes activities. oxygen had an evident ef ...199418618780
relation between dissolved oxygen concentration and ajmalicine production rate in high-density cultures of catharanthus roseus.the relation between dissolved oxygen (do) and the ajmalicine production rate of catharanthus roseus was investigated in 15-l tank reactors at constant stirrer speed and gas flow rate. below a do concentration of 29% of air saturation the ajmalicine production rate was less than 0.06 micromol/g/d. above a do of 43% the ajmalicine production rate was constant at 0.21 micromol/g/d. between a do of 29% and 43% there was a strong relation between the ajmalicine production rate and the do concentrati ...199518623236
two-stage batch process for the production of ajmalicine by catharanthus roseus: the link between growth and production stage.the link between the growth stage and the production stage in a two-stage batch process was investigated using (filtered) inocula from different periods of the stationary phase of the growth cycle. in the production stage, ajmalicine production by catharanthus roseus in a 3-l stirred tank reactor was induced with a high glucose concentration (80 g/l). ajmalicine production in cultures started with cells from the late stationary phase was five times higher than in cultures started with cells from ...199518623366
the role of glucose in ajmalicine production by catharanthus roseus cell cultures.the role of glucose in ajmalicine production by catharanthus roseus was investigated in the second stage of a two-stage batch process. activities of tryptophan decar-boxylate (tdc) and anthranilate synthase (as), two enzymes in the pathway leading to ajmalicine, were higher after induction with 40 g/l glucose than after induction with 60 or 80 g/l glucose. experiments with different media containing mixtures of glucose and the nonpermeating osmotic agent xylose, and using an already induced cult ...199518623431
transient studies of nutrient uptake, growth, and indole alkaloid accumulation in heterotrophic cultures of hairy roots of catharanthus roseus.the kinetics of growth, the uptake of macronutrients, and the accumulation of indole alkaloids were investigated in long-term, heterotrophically cultured transgenic ("hairy") roots of catharanthus roseus.tabersonine, ajmalicine, and serpentine were monitored over a 70-day period. the doubling time [dry-weight (dw) basis] of c. roseus hairy roots in b5/2 nutrients supplemented with 3% sucrose was 3.6 days. nh(4)(+), no(3),(-) and p(i) were depleted sequentially from culture medium by hairy roots, ...199718636519
seasonal population dynamics of draeculacephala minerva (hemiptera: cicadellidae) and transmission of xylella fastidiosa.the grass sharpshooter, draeculacephala minerva ball (hemiptera: cicadellidae), is a very common and often abundant grass-feeding leafhopper in california. its population dynamics and ability to transmit xylella fastidiosa were monitored over a 2-yr period in california's san joaquin valley. collections of individuals from natural populations in irrigated pastures and alfalfa, medicago savita l. fields adjacent to x. fastidiosa-infected almond (prunus spp.) orchards indicated the occurrence of t ...200818767716
characterization of the phenylalanine ammonia-lyase gene (slpal5) from tomato (solanum lycopersicum l.).phylogenetic analysis based on the deduced amino acid sequence of phenylalanine ammonia-lyase gene (slpal5) cdna from tomato (solanum lycopersicum l.) revealed high sequence similarity to pal genes in nicotiana tabacum (92%), ipomoea nil (87%), manihot esculenta (84%), and catharanthus roseus (84%). the slpal5 gene exists as multiple copies in the tomato plant, and its transcription was strongly expressed in old leaves and flowers. from 5 days post-anthesis to the onset of ripening, slpal5 expre ...200918791854
proteins prenylated by type i protein geranylgeranyltransferase act positively on the jasmonate signalling pathway triggering the biosynthesis of monoterpene indole alkaloids in catharanthus roseus.in catharanthus roseus, the first step of monoterpenoid indole alkaloids (mia) biosynthesis results from the condensation of the indole precursor tryptamine with the terpenoid precursor secologanin. secologanin biosynthesis requires two successive biosynthetic pathways, the plastidial methyl-d: -erythritol 4-phosphate (mep) pathway and the monoterpene secoiridoid pathway. in c. roseus cell culture, the expression of several genes encoding enzymes of these two pathways is dramatically down-regula ...200918813931
differential secretion and accumulation of terpene indole alkaloids in hairy roots of catharanthus roseus treated with methyl jasmonate.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 t ...200918841500
new phenolic compounds and antioxidant potential of catharanthus roseus.screening of the phenolic compounds from seeds, stems, leaves and petals of catharanthus roseus (l.) g. don (cv. little bright eye) was achieved by hplc-dad-esi-ms/ms. this is the first detailed study of noncolored phenolics in c. roseus, which allowed the characterization of three caffeoylquinic acids and fifteen flavonol glycosides (di- and trisaccharides of kaempferol, quercetin and isorhamnetin). fifteen compounds are reported for the first time in this species. the scavenging ability of the ...200818850714
endogenous hormonal and enzymatic responses of catharanthus roseus with triadimefon application under water deficits.the effect of triadimefon was investigated in a medicinal plant, catharanthus roseus subjected to water deficit stress. the abscisic acid (aba) level, dna and rna contents and activities of atpase and protease were found varying in different parts of the plants under treatment. drought treatment increased the aba level more than twofold in all parts of the plants. tdm treatment to the drought stressed plants showed highest contents. in roots, stem and leaves, drought stress caused a decrease in ...200818940699
nonphytotoxic aluminum-peat complexes suppress phytophthora parasitica.abstract amendment of peat-based potting media with al(2)(so(4))(3) suppresses damping-off of vinca (catharanthus roseus) caused by phytophthora parasitica. the species of aluminum (al) responsible for disease suppression have not been identified. the objective of this study was to determine the effects of amount and ph of al(2)(so(4))(3) amendment solutions on survival of p. parasitica. in separate experiments, peat was amended with al(2)(so(4))(3) solutions adjusted to ph 4 or 6 at either 0.01 ...200118943446
causal role of xylella fastidiosa in oleander leaf scorch disease.abstract a lethal leaf scorch disease of oleander (nerium oleander) appeared in southern california in 1993. a bacterium, xylella fastidiosa, was detected by culturing, enzyme-linked immunoassay, and polymerase chain reaction in most symptomatic plants but not in symptomless plants or negative controls. inoculating oleanders mechanically with x. fastidiosa cultures from diseased oleanders caused oleander leaf scorch (ols) disease. the bacterium was reisolated from inoculated plants that became d ...199918944803
pathogenicity of aster yellows phytoplasma and spiroplasma citri on periwinkle.abstract using murashige and skoog (ms) as a basal medium, the effects of varying levels and combinations of plant growth regulators required for shoot tip and root proliferation in healthy and aster yellows phytoplasma (ayp)- and spiroplasma citri-infected periwinkle (catharanthus roseus) shoots were studied. number of shoots and fresh and dry mass of healthy and ayp-infected shoots increased when benzyladenine (ba) concentrations were increased from 0.5 to 4 mg/liter. the maximum number of sho ...199818944838
transcriptional response of the terpenoid indole alkaloid pathway to the overexpression of orca3 along with jasmonic acid elicitation of catharanthus roseus hairy roots over time.jasmonic acid (ja) activates the transcriptional regulator orca3, which has a role in regulating the terpenoid indole alkaloid (tia) pathway within catharanthus roseus. the tia pathway leads to the production of the anticancer drugs vinblastine and vincristine. this work explores the transient effects of overexpressing orca3 under the control of a glucocorticoid-inducible promoter system in c. roseus hairy roots along with the simultaneous feeding of ja. the changes in tia metabolites and in mrn ...200918955153
a differential response to chemical elicitors in catharanthus roseus in vitro cultures.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 ethylen ...200919030782
five year maintenance of the inducible expression of anthranilate synthase in catharanthus roseus hairy roots.transgenic hairy root cultures have the potential to be an industrial production platform for a variety of chemicals. this report demonstrates the long-term stability of a transgenic catharanthus roseus hairy root line containing the inducible expression of a feedback-insensitive anthranilate synthase (as). after 5 years in liquid culture, the presence of the inserted as gene was confirmed by genomic pcr. the inducible expression of as was confirmed by enzyme assay and by changes in terpenoid in ...200919031426
low levels of gibberellic acid control the biosynthesis of ajmalicine in catharanthus roseus cell suspension cultures.in periwinkle cell suspensions, amounts of gibberellic acid ranging from 10 ( - 10) m to 10 ( - 7) m significantly antagonized, in a dose-dependant manner, the stimulation of ajmalicine biosynthesis by cytokinins (cks). this inhibitory effect was strictly correlated with the abolition of the expression of two genes encoding enzymes of the monoterpenoid indole alkaloid (mia) biosynthetic pathway and was normally upregulated after ck treatments. moreover, low concentrations of the gibberellin bios ...200919096998
auxin-treatment induces recovery of phytoplasma-infected periwinkle.to test the effect of auxin-treatment on plant pathogenic phytoplasmas and phytoplasma-infected host.200819120631
[effects of nacl on the growth and alkaloid content of catharanthus roseus seedlings].catharanthus roseus seedlings were grown in 1/2 hoagland solution containing 0-250 mmol x l(-1) of nacl, and their fresh and dry mass, malondialdehyde (mda) and chlorophyll contents, tryptophan decarboxylase (tdc) and peroxidase (pod) activities, and vindoline, catharanthine, vincristine and vinblastine contents were measured after 7 days. the results showed that nacl markedly decreased the fresh and dry mass but increased the mda content. the chlorophyll content had no difference with the contr ...200819123347
metabolic reprogramming of periwinkle plant culture.we transformed an alkaloid biosynthetic gene with reengineered substrate specificity into catharanthus roseus. the resulting transgenic plant cell culture produced a variety of unnatural alkaloid compounds when cocultured with simple, achiral, commercially available precursors that the reengineered enzyme was designed to accept. this work demonstrates the power of genetic engineering to retailor the structures of complex alkaloid natural products in plant culture.200919151732
volatile composition of catharanthus roseus (l.) g. don using solid-phase microextraction and gas chromatography/mass spectrometry.a total of 88 volatile and semi-volatile components were formally or tentatively identified in flowers, leaves and stems of catharanthus roseus (l.) g. don (cv. little bright eye), by headspace solid-phase microextraction (hs-spme) and by dichloromethane extraction, combined with gas chromatography-mass spectrometry (gc-ms). these include some diterpenic compounds (manool and manoyl oxides), a sesquiterpen (alpha-bisabolol), and some pyridine, pyrazine, indol and carotenoid derivatives. applying ...200919186019
a phytoplasma related to 'candidatus phytoplasma asteri' detected in citrus showing huanglongbing (yellow shoot disease) symptoms in guangdong, p. r. china.citrus huanglongbing (hlb) or yellow shoot disease (i.e., greening disease) is highly destructive to citrus production worldwide. understanding the etiology of hlb is critical for managing the disease. hlb is currently associated with infection by 'candidatus liberibacter spp.' around the world, including china. however, koch's postulates have not been fulfilled. in addition, other plant pathogens also may be involved in hlb. in a survey performed in guangdong province, p. r. china in 2006 and 2 ...200919203275
two distinct intracellular ca2+-release components act in opposite ways in the regulation of the auxin-dependent mia biosynthesis in catharanthus roseus cells.calcium-mediated signalling is ubiquitous in both animals and plants. changes in cytoplasmic free ca(2+) concentration couple diverse arrays of stimuli to their specific responses, the specificity of the stimulus being determined by integrated actions between multiple ca(2+) mobilization pathways. in this work, a pharmacological approach is reported, aimed at deciphering the role of calcium as a second messenger in the transduction pathway leading to the inhibitory effect of 2,4-dichlorophenoxya ...200919218316
biosynthesis of salicylic acid in fungus elicited catharanthus roseus cells.feeding experiments using [1-(13)c]-d-glucose to catharanthus roseus (l.) g.don cell suspension cultures followed by elicitation with pythium aphanidermatum extract were performed in order to study the salicylic acid (sa) biosynthetic pathway and that of 2,3-dihydroxybenzoic acid (2,3-dhba) as a comparison. a strongly labeled c-7 and a symmetrical partitioning of the label between c-2 and c-6 would occur if sa was synthesized from phenylalanine. in case of the isochorismate pathway, a relatively ...200919251288
effects of solarization and ammonium amendments on plant-parasitic nematodes.the effects of soil solarization and ammonium bicarbonate or ammonium sulfate against plant-parasitic nematodes on yellow squash (cucurbita pepo) and on vinca (catharanthus roseus) were evaluated at two sites. solarization for 3 weeks in the spring suppressed population levels of belonolaimus longicaudatus, criconemella spp., and dolichodorus heterocephalus throughout the growing season on both crops at both sites. levels of meloidogyne incognita were suppressed initially, but population densiti ...200019271007
flavonoid glucosides from the hairy roots of catharanthus roseus.four new flavonoid glucosides, 3',4'-di-o-methylquercetin-7-o-[(4''-->13''')-2''',6''',10''',14'''-tetramethylhexadec-13'''-ol-14'''-enyl]-beta-d-glucopyranoside (1), 4'-o-methylkaempferol-3-o-[(4''-->13''')- 2''',6''',10''',14'''-tetramethylhexadecan-13'''-olyl]-beta-d-glucopyranoside (2), 3',4'-di-o-methylbutin-7-o-[(6''-->1''')-3''',11'''-dimethyl-7'''-methylenedodeca-3''',10'''-dienyl]-beta-d-glucopyranoside (3), and 4'-o-methylbutin-7-o-[(6''-->1''')-3''',11'''-dimethyl-7'''-hydroxymethylen ...200919271765
sensitivity of bedding plants to southern root-knot nematode, meloidogyne incognita race 3.thirty-two cultivars of 10 commonly-grown bedding plants, representing eight families, were evaluated for their response to infection by the root-knot nematode, meloidogyne incognita race 3, under greenhouse conditions. four ageratum cultivars, two marigold, and two salvia cultivars were rated resistant after exposure for 8 weeks. four begonia, four celosia, one dianthus, one verbena, one vinca, and three pansy cultivars were susceptible. three salvia, one begonia, one gerber, one verbena, and t ...199419279964
production and metabolic engineering of terpenoid indole alkaloids in cell cultures of the medicinal plant catharanthus roseus (l.) g. don (madagascar periwinkle).the madagascar periwinkle [catharanthus roseus (l.) g. don] is a plant species known for its production of tias (terpenoid indole alkaloids), many of which are pharmaceutically important. ajmalicine and serpentine are prescribed for the treatment of hypertension, whereas the bisindoles vinblastine, vincristine and 3',4'-anhydrovinblastine are used for their antineoplastic activity in the treatment of many cancers. however, tias are produced in small yields in c. roseus, which make them expensive ...200919281450
tests for transmission of prunus necrotic ringspot and two nepoviruses by criconemella xenoplax.in two of three trials, detectable color reactions in elisa for prunus necrotic ringspot virus (pnrsv) were observed for criconemella xenoplax handpicked from the root zone of infected peach trees. criconemella xenoplax (500/pot) handpicked from root zones of peach trees infected with pnrsv failed to transmit the virus to cucumber or peach seedlings. the nematode also failed to transmit tomato ringspot (tomrsv) or tobacco ringspot viruses between cucumbers, although xiphinema americanum transmit ...199019287748
targeted metabolite analysis of catharanthus roseus and its biological potential.catharanthus roseus is nowadays one of the most studied medicinal plants. in this work, further knowledge on different parts of this species (leaves, stems, seeds and petals) was achieved, namely phenolics by hplc-dad and organic acids and amino acids by hplc-uv. also, the biological potential, expressed as acetylcholinesterase inhibitory activity was accessed and, in some parts, an acetylcholinesterase inhibitory capacity higher than 85% was found (ic(50) at 422, 442 and 2683 microg/ml in leave ...200919298840
[analysis of catharanthine content and agronomic traits in catharanthus roseus].catharanthine content and agronomic traits in major catharanthus roseus varieties were analyzed. it was found that there existed great difference in catharanthine content and agronomic traits among the varieties. catharanthine content was the highest in variety pacifica polka dot (ppd), reaching 3.79 mg g(-1) dry leaf weight, and the lowest in variety cooler pink (cp) with only 0.9 mg g(-1) dry leaf weight. correlation existed in certain extent between catharanthine content and agronomic traits ...200919385168
improved accumulation of ajmalicine and tetrahydroalstonine in catharanthus cells expressing an abc transporter.the biosynthetic pathway of monoterpenoid indole alkaloids in catharanthus roseus is located throughout various membranes at both the cellular and intercellular levels. atp-binding cassette (abc) transporters are known to export vincristine and vinblastine from human cancer cells. it has recently been shown that abc transporters are also involved in the transport of various monoterpenoid alkaloids in catharanthus roseus cells. over-expression of an abc transporter in this plant might therefore a ...200919403195
the role of the octadecanoid pathway in the production of terpenoid indole alkaloids in catharanthus roseus hairy roots under normal and uv-b stress conditions.the octadecanoid pathway is responsible for producing jasmonic acid an important signaling molecule in plants, which controls the production of a variety of secondary metabolites. previously the exogenous addition of jasmonic acid to catharanthus roseus hairy roots caused an increase in terpenoid indole alkaloid (tia) accumulation. the role of the endogenous production of jasmonic acid by the octadecanoid pathway in the production of tias in c. roseus hairy roots is examined. feeding of octadeca ...200919437555
the effects of uv-b stress on the production of terpenoid indole alkaloids in catharanthus roseus hairy roots.in nature, plants generate protective secondary metabolites in response to environmental stresses. such metabolites include terpenoid indole alkaloids (tias), which absorb uv-b light and serve putatively to protect the plant from harmful radiation. catharanthus roseus plants, multiple shoot cultures, and cell suspension cultures exposed to uv-b light show significant increases in the production of tias, including precursors to vinblastine and vincristine, which have proven effective in the treat ...200919479674
optimization of the transient transformation of catharanthus roseus cells by particle bombardment and its application to the subcellular localization of hydroxymethylbutenyl 4-diphosphate synthase and geraniol 10-hydroxylase.the monoterpene indole alkaloids (mia) synthesized in catharanthus roseus are highly valuable metabolites due to their pharmacological properties. in planta, the mia biosynthetic pathway exhibits a complex compartmentation at the cellular level, whereas subcellular data are sparse. to gain insight into this level of organization, we have developed a high efficiency green fluorescent protein (gfp) imaging approach to systematically localize mia biosynthetic enzymes within c. roseus cells followin ...200919504099
isolation of microsatellites from catharanthus roseus (l.) g. don using enriched libraries.catharanthus roseus is an indispensable source of the anticancerous alkaloids-vincristine and vinblastine, even though they are produced in trace amounts in vivo. in order to increase the yield of alkaloids, in vitro tissue culture studies are carried out which result in a large number of lines/cultures. for identification and characterization of the in vitro cultures, microsatellites in the form of stms (sequenced tagged microsatellite sites) markers are used for identification of genetic polym ...200919521853
bioreactor production of secondary metabolites from cell cultures of periwinkle and sandalwood.a bench-top bioreactor allowing continuous extraction of secondary metabolites is designed for catharanthus roseus l. (g.) don (periwinkle) and santalum album l. (sandalwood) plant cell suspensions. periwinkle cell cultures are exposed to biotic elicitors (aspergillus niger, crude chitin) and abiotic elicitors (mannitol, methyl jasmonate) to induce alkaloid production. whereas most of the biotic elicitors are effective when added on day 15 of culture, the abiotic elicitors are effective when add ...200919521856
increased vincristine production from agrobacterium tumefaciens c58 induced shooty teratomas of catharanthus roseus g. don.dimeric indole alkaloids are used extensively for cancer therapy. agrobacterium tumefaciens c58 strain was used for induction of shooty teratoma in catharanthus roseus using epicotyl and stem node explants. the transformed nature of shooty teratomas was confirmed by nopaline assay. growth kinetics of shooty teratomas depicted maximum growth during 21-24 days of culture. dimeric alkaloid vincristine in the transformed cultures was present at a concentration of 0.011 that was tenfold higher compar ...200919521912
overexpression of the hmg-coa reductase gene leads to enhanced artemisinin biosynthesis in transgenic artemisia annua plants.an effective and affordable treatment against malaria is still a challenge for medicine. most contemporary drugs either are too expensive to produce or are not effective against resistant strains of the malaria parasite plasmodium falciparum. the plant artemisia annua l. is the source of artemisinin, an effective drug against malaria for which no resistant strains of the bacterium have been reported. however, the artemisinin content of a. annua is very low, which makes its production expensive. ...200919551613
comparison of hypotensive and hypolipidemic effects of catharanthus roseus leaves extract with atenolol on adrenaline induced hypertensive rats.the leaves extract of catharanthus roseus was investigated for hypotensive and hypolipidemic effects in adrenaline-induced hypertensive rats (aihr) and compared with those of atenolol in a crossover design. the pharmacologically active components responsible for hypotensive activities were isolated from plant using bioassay guided purification approach and the structure of the compounds was proposed by spectroscopic methods. catharanthus roseus leaves extract and commercial drug atenolol were ad ...200919553172
functional and structural characterization of a flavonoid glucoside 1,6-glucosyltransferase from catharanthus roseus.sugar-sugar glycosyltransferases play an important role in structural diversity of small molecule glycosides in higher plants. we isolated a cdna clone encoding a sugar-sugar glucosyltransferase (caugt3) catalyzing 1,6-glucosylation of flavonol and flavone glucosides for the first time from catharanthus roseus. caugt3 exhibited a unique glucosyl chain elongation activity forming not only gentiobioside but also gentiotrioside and gentiotetroside in a sequential manner. we investigated the functio ...200919561332
growth inhibitory activity of fatty acid methyl esters in the whole seed oil of madagascar periwinkle (apocyanaceae) against helicoverpa armigera (lepidoptera: noctuidae).crude hexane and water extracts of catharanthus roseus linn. (syn: vinca rosea) (apocyanaceae) stem, leaf, and seed exhibited pesticidal activity against helicoverpa armigera (hübner) (lepidoptera noctuidae). the extracts differed significantly in their efficacy, with the crude hexane extract of whole seed being the most effective in curtailing pupal survivorship to 18% followed by the hexane extracts of leaf (21%) and stem (24%). average pupal weight (68.2 mg) and length (1.5 cm) in the whole s ...200919610438
silencing of tryptamine biosynthesis for production of nonnatural alkaloids in plant culture.natural products have long served as both a source and inspiration for pharmaceuticals. modifying the structure of a natural product often improves the biological activity of the compound. metabolic engineering strategies to ferment "unnatural" products have been enormously successful in microbial organisms. however, despite the importance of plant derived natural products, metabolic engineering strategies to yield unnatural products from complex, lengthy plant pathways have not been widely expl ...200919666570
metabolic changes of salicylic acid-elicited catharanthus roseus cell suspension cultures monitored by nmr-based metabolomics.the effect of salicylic acid (sa) on the metabolic profile of catharanthus roseus suspension cells throughout a time course (0, 6, 12, 24, 48 and 72 h after treatment) was investigated using nmr spectroscopy and multivariate data analysis. when compared to control cell lines, sa-treated cells showed a high level of sugars (glucose and sucrose) up to 48 h after treatment, followed by a dynamic change in amino acids, phenylpropanoids, and tryptamine. additionally, one compound--2,5-dihydroxybenzoi ...200919701606
a vacuolar class iii peroxidase and the metabolism of anticancer indole alkaloids in catharanthus roseus: can peroxidases, secondary metabolites and arabinogalactan proteins be partners in microcompartmentation of cellular reactions?plants possess a unique metabolic diversity commonly designated as secondary metabolism, of which the anticancer alkaloids from catharanthus roseus are among the most studied. recently, in a classical function-to-protein-to-gene approach, we have characterized the main class iii peroxidase (prx) expressed in c. roseus leaves, crprx1, implicated in a key biosynthetic step of the anticancer alkaloids. we have shown the vacuolar sorting determination of crprx1 using gfp fusions and we have obtained ...200819704535
simple and reproducible hplc-dad-esi-ms/ms analysis of alkaloids in catharanthus roseus roots.catharanthus roseus is one of the most important medicinal plants worldwide. the leaves of this species are the only source of the indolomonoterpenic alkaloids vincristin (leurocristine) and vinblastin (vincaleucoblastine), whose anticancer activity represents powerful therapeutics to many diseases, such as hodgkin lymphoma. usually, the remaining plant parts go to waste. here we describe a phytochemical study on this species roots. alkaloids in aqueous extracts, the usual form of consumption of ...201019720492
assessing the limitations to terpenoid indole alkaloid biosynthesis in catharanthus roseus hairy root cultures through gene expression profiling and precursor feeding.the production of pharmaceutically important terpenoid indole alkaloids (tias) from catharanthus roseus is partly regulated at the transcriptional level. in this study, limitations in tia biosynthesis from c. roseus hairy root cultures were assessed through gene expression profiling and precursor feeding. the transcript levels of key tia pathway genes (g10h, tdc, str, and sgd) and metabolite levels associated with the tia pathway (tryptamine, loganin, secologanin, strictosidine, ajmalicine, serp ...201219722248
metabolic discrimination of catharanthus roseus calli according to their relative locations using (1)h-nmr and principal component analysis.creating a plant-cell suspension culture involves first transferring the callus into liquid media, but there are no objective criteria for selecting the location of the callus to be transferred. in this study, inner and outer cells of catharanthus roseus with various elicitors in solid-state cultures were differentiated by (1)h nmr (nuclear magnetic resonance) spectrometry and principal component analysis (pca). it was found that the samples of various elicitors and relative locations could be s ...200919734668
transmission of different isolates of spiroplasma citri to carrot and citrus by circulifer tenellus (hemiptera: cicadellidae).carrot purple leaf disease was first reported in 2006 in the state of washington and was associated with spiroplasma citri. the disease also was reported in california in 2008. the objectives of this work were to fulfill koch's postulates and to determine 1) whether the beet leafhopper, circulifer tenellus (baker) (hemiptera: cicadellidae), transmits carrot [daucus carota l. subsp. sativus (hoffm.) arcang] isolates of s. citri; and 2) whether carrot and citrus [citrus sinensis (l.) osb.]-derived ...200919736751
response of mycorrhizal periwinkle plants to aster yellows phytoplasma infection.the objective of our research was to assess if arbuscular mycorrhizal (am) fungal colonization can modify the effect of infection by two aster yellows phytoplasma strains (ay1, aysim) in catharanthus roseus plants. both phytoplasma strains had a negative effect on the root fresh weight, but they differed in symptoms appearance and in their influence on photosynthetic and transpiration rates of the periwinkle plants. am plants showed significantly reduced shoot fresh weight, while the transpirati ...201019756778
transmission of methylobacterium mesophilicum by bucephalogonia xanthophis for paratransgenic control strategy of citrus variegated chlorosis.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 fro ...200919763419
oral glucose tolerance test (ogtt) in normal control and glucose induced hyperglycemic rats with coccinia cordifolia l. and catharanthus roseus l.the aim of this study is to investigate the hypoglycemic effects of petroleum ether, chloroform and ethyl acetate fractions isolated from ethanolic extracts of coccinia cordifolia and catharanthus roseus on normal control and orally glucose-induced hyperglycemic rats. single doses (150 mg/kg) of different fractions of c. cordifolia and c. roseus extracts were intraperitonelly administered. the serum blood glucose level was obtained by pricking the tail vein using glucometer at time 0, 30, 60, 90 ...200919783519
mass attenuation coefficients of x-rays in different medicinal plants.the mass attenuation coefficients of specific parts of several plants, (fruits, leaves, stem and seeds) often used as medicines in the indian herbal system, have been measured employing nai (ti)) detector. the electronic setup used is a nai (ti) detector, which is coupled to mca for analysis of the spectrum. a source of (241)am is used to get x-rays in the energy range 8-32kev from cu, rb, mo, ag and ba targets. in the present study, the measured mass attenuation coefficient of ocimum sanctum, c ...201019910203
pharmacological effects of catharanthus roseus root alkaloids in acetylcholinesterase inhibition and cholinergic neurotransmission.the leaves of catharanthus roseus constitute the only source of the well known indolomonoterpenic alkaloids vincristine and vinblastine. in this work we studied the biological potential of the roots, which are used in several countries as decocts or hot water extracts for the treatment of a number of conditions. the aqueous extract strongly inhibited acetylcholinesterase (ache) in an in vitro microassay, an effect ascribable mainly to serpentine (ic(50) = 0.775 microm vs physostigmine ic(50) = 6 ...201019962870
isolation and functional analysis of the catharanthus roseus deacetylvindoline-4-o-acetyltransferase gene promoter.madagascar periwinkle (catharanthus roseus) produces many therapeutically valuable terpenoid indole alkaloids (tias), such as vinblastine and vincristine derived from the monomers vindoline and catharanthine. deacetylvindoline-4-o-acetyltransferase (dat) is a key enzyme for the terminal step of vindoline biosynthesis. in this research, the dat gene promoter was cloned, sequenced, and analyzed. an approximately 1,773 bp genomic dna fragment of dat promoter was obtained. sequence analysis revealed ...201020035334
aza-tryptamine substrates in monoterpene indole alkaloid biosynthesis.biosynthetic pathways can be hijacked to yield novel compounds by introduction of novel starting materials. here we have altered tryptamine, which serves as the starting substrate for a variety of alkaloid biosynthetic pathways, by replacing the indole with one of four aza-indole isomers. we show that two aza-tryptamine substrates can be successfully incorporated into the products of the monoterpene indole alkaloid pathway in catharanthus roseus. use of unnatural heterocycles in precursor-direct ...200920064432
gene expression profiling of phytoplasma-infected madagascar periwinkle leaves using differential display.phytoplasmas are small (0.2-0.8 μm), wall-less, pleiomorphic prokaryotes responsible of numerous economically important plant diseases. they are characterized by a very small genome and are obligate parasites of phloem tissues and some insects that act as vectors of infection. to investigate molecular mechanisms involved in pathogenesis, the differential display technique was here applied to identify plant genes whose transcription was significantly altered in leaves of madagascar periwinkle (ca ...201120127177
screening molecules for control of citrus huanglongbing using an optimized regeneration system for 'candidatus liberibacter asiaticus'-infected periwinkle (catharanthus roseus) cuttings.citrus huanglongbing is one of the most destructive diseases of citrus worldwide. the disease is associated with three different species of 'candidatus liberibacter', of which 'ca. l. asiaticus' is the most widely distributed. an optimized system using 'ca. l. asiaticus'-infected periwinkle cuttings was developed to screen chemical compounds effective for controlling the bacterial population while simultaneously assessing their phytotoxicity. the optimal regeneration conditions were determined t ...201020128697
synthesis of anti-tumor dimeric indole alkaloids in catharanthus roseus was promoted by irradiation with near-ultraviolet light at low temperature.we have found that coupling between catharanthine and vindoline occurs non-enzymatically in the presence of flavin mononucleotide and manganese ions with near-ultraviolet light irradiation in vitro. the present study found that the concentrations of catharanthine and vindoline in catharanthus roseus decreased and those of dimeric indole alkaloids increased under near-ultraviolet light at 4 degrees c. it indicates that this coupling reaction at 4 degrees c occurs non-enzymatically.201020139608
effects of hydrostatic pressure, agitation and co2 stress on phytophthora nicotianae zoospore survival.phytophthora nicotianae breda de haan is a common pathogen of ornamental plants in recycled irrigation systems. in a previous study, annual vinca (catharanthus roseus don) inoculated with zoospore suspensions using a co(2)-pressurized sprayer had less foliage blight than plants inoculated using a hand sprayer. here, the impact of hydrostatic pressure, agitation and aeration with co(2) on the survival of p. nicotianae zoospores was examined.201020201053
isolation and characterization of antineoplastic alkaloids from catharanthus roseus l. don. cultivated in egypt.vinblastine and vincristine (the antileukemic agents) were isolated, in a pure form, from catharanthus roseus l. don., cultivated in egypt, by several chromatographic techniques. five modified methods for the preparation of total alkaloids were carried out. all the isolated mixtures were evaluated by hplc and hptlc analyses. the antineoplastic alkaloids; vinblastine and vincristine, were isolated by the use of vacuum liquid chromatographic column on silica gel : aluminium oxide (1:1) mixed bed v ...200920209002
influence of cellular differentiation and elicitation on intermediate and late steps of terpenoid indole alkaloid biosynthesis in catharanthus roseus.the invaluable antineoplastic bisindole alkaloids of catharanthus roseus and their precursor, vindoline, are not produced in cell cultures. the intricacies involved in endogenous (cellular differentiation) and exogenous (elicitation) regulation of their biosynthesis need to be dissected out for favorable exploitation. this study aimed at elucidating the effect of pythium aphanidermatum homogenate and methyl jasmonate (meja) on in vitro cultures (of cv. 'dhawal') representing increasing level of ...201020217156
increasing anthraquinone production by overexpression of 1-deoxy-d: -xylulose-5-phosphate synthase in transgenic cell suspension cultures of morinda citrifolia.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 tumefaci ...201020349334
biotransformation of artemisinin using cell suspension cultures of catharanthus roseus (l.) g.don and lavandula officinalis l.artemisinin, an antimalarial compound, at 5 mg/40 ml, was transformed by cell suspension cultures of catharanthus roseus (l.) g.don and lavandula officinalis l. into deoxyartemisinin with yields >78% (3.93 mg deoxyartemisinin from 5 mg artemisinin). maximum conversion (78.6 and 78%) occurred after 6 and 7 days of adding artemisinin to 20 and 9 days old cultures of c. roseus and l. officinalis, respectively. the procedure was scaled up by and 500 mg artemisinin was transformed into 390 mg deoxyar ...201020369274
medicinal plants used for the treatment of diarrhoea in northern maputaland, kwazulu-natal province, south africa.to document the ethnobotanical knowledge on antidiarrhoeal plant use by lay people in a rural community in northern maputaland.201020452415
zoospore density-dependent behaviors of phytophthora nicotianae are autoregulated by extracellular products.phytophthora species are destructive fungus-like plant pathogens that use asexual single-celled flagellate zoospores for dispersal and plant infection. many of the zoospore behaviors are density-dependent although the underlying mechanisms are poorly understood. here, we use p. nicotianae as a model and demonstrate autoregulation of some zoospore behaviors using signal molecules that zoospores release into the environment. specifically, zoospore aggregation, plant targeting, and infection requir ...201020528180
overexpression of g10h and orca3 in the hairy roots of catharanthus roseus improves catharanthine production.a number of genes that function in the terpenoid indole alkaloids (tias) biosynthesis pathway have been identified in catharanthus roseus. except for the geraniol 10-hydroxylase (g10h) gene, which encodes a cytochrome p450 monooxygenase, several of these genes are up-regulated by orca3, a jasmonate-responsive apetala2 (ap2)-domain transcript factor. in this study, the g10h gene was transformed independently, or co-transformed with orca3 into c. roseus, using agrobacterium rhizogenes msu440. hair ...201020535474
effect of loss of t-dna genes on mia biosynthetic pathway gene regulation and alkaloid accumulation in catharanthus roseus hairy roots.hairy roots are generated by integration of t-dna in host plant genome from root inducing (ri) plasmid of agrobacterium rhizogenes and have been utilized for production of secondary metabolites in different plant systems. in catharanthus roseus, hairy roots are known to show different morphologies, growth patterns, and alkaloid contents. it is also known that during transformation, there is a differential loss of a few t-dna genes. to decipher the effect of loss of t-dna genes on the various asp ...201020625736
cytotoxicity of vinca minor.vinca minor l. (apocynaceae) is a medicinal plant that has long been used to treat cerebral and memory disorders in european folk medicine. furthermore, it contains more than 50 alkaloids, some of them having bisindole structure such as the antineoplastic alkaloids present in catharanthus roseus (l.) g. don (apocynaceae). in this study, the plant's alkaloid extract was divided into three fractions and the cytotoxic effects on cell proliferation of ht-29, caco-2, t47d, and nih/3t3 cell lines were ...201020645762
vinca drug components accumulate exclusively in leaf exudates of madagascar periwinkle.the monoterpenoid indole alkaloids (mias) of madagascar periwinkle (catharanthus roseus) continue to be the most important source of natural drugs in chemotherapy treatments for a range of human cancers. these anticancer drugs are derived from the coupling of catharanthine and vindoline to yield powerful dimeric mias that prevent cell division. however the precise mechanisms for their assembly within plants remain obscure. here we report that the complex development-, environment-, organ-, and c ...201020696903
cloning and functional analysis of geraniol 10-hydroxylase, a cytochrome p450 from swertia mussotii franch.swertia mussotii franch has anti-hepatitis activity and contains a high level of iridoid monoterpenoids. the cytochrome p450 monooxygenase (cyp) geraniol 10-hydroxylase (g10h) is thought to play an important role in iridoid monoterpenoid and indole alkaloid biosynthesis. here we report the isolation of a full-length cdna clone of s. mussotii g10h (smg10h). the predicted gene product was a 496 residue protein designated cyp76b10, the sequence of which was highly similar to that of the cyp76 famil ...201020699579
uv-b induced transcript accumulation of dahp synthase in suspension-cultured catharanthus roseus cells.the enzyme 3-deoxy-d-arabino-heptulosonate-7-phosphate (dahp) synthase (ec 4.1.2.15) catalyzes the first committed step in the shikimate pathway of tryptophan synthesis, an important precursor for the production of terpenoid indole alkaloids (tias). a full-length cdna encoding nuclear coded chloroplast-specific dahp synthase transcript was isolated from a catharanthus roseus cdna library. this had high sequence similarity with other members of plant dahp synthase family. this transcript accumula ...201020704760
transcriptional response of the catharanthine biosynthesis pathway to methyl jasmonate/nitric oxide elicitation in catharanthus roseus hairy root culture.jasmonates and nitric oxide (no) play important roles in the regulation of the signaling network leading to the biosynthesis of plant secondary metabolites. in this work, we explore the effect of constitutive overexpression of crorca3 (octadecanoid-responsive catharanthus ap2/erf domain), methyl jasmonate (meja), and sodium nitroprusside (snp) on the differentiated tissue of catharanthus roseus hairy roots. the changes in catharanthine concentration and in the levels of mrna transcripts of pathw ...201020714717
strictosidine activation in apocynaceae: towards a "nuclear time bomb"?the first two enzymatic steps of monoterpene indole alkaloid (mia) biosynthetic pathway are catalysed by strictosidine synthase (str) that condensates tryptamine and secologanin to form strictosidine and by strictosidine beta-d-glucosidase (sgd) that subsequently hydrolyses the glucose moiety of strictosidine. the resulting unstable aglycon is rapidly converted into a highly reactive dialdehyde, from which more than 2,000 mias are derived. many studies were conducted to elucidate the biosynthesi ...201020723215
biochemical and epigenetic changes in phytoplasma-recovered periwinkle after indole-3-butyric acid treatment.to elucidate the possible mechanism of phytoplasma elimination from periwinkle shoots caused by indole-3-butyric acid (iba) treatment.201020796083
new method to enhance ajmalicine production in catharanthus roseus cell cultures based on the use of cyclodextrins.the joint use of cyclodextrins and methyljasmonate, when accompanied by a short exposure to uv, enhanced extracellular ajmalicine accumulation to 1040 ± 26.6 mg/l in suspension cultured cells of catharanthus roseus. the success of this strategy is due to the use of cyclodextrins, which not only induce ajmalicine biosynthesis but also promote adduct formation. this removes ajmalicine from the medium, reduces feedback inhibition and ajmalicine degradation, and allows its accumulation in the cultur ...201120953668
homolog of tocopherol c methyltransferases catalyzes n methylation in anticancer alkaloid biosynthesis.madagascar periwinkle (catharanthus roseus) is the sole source of the anticancer drugs vinblastine and vincristine, bisindole alkaloids derived from the dimerization of the terpenoid indole alkaloids vindoline and catharanthine. full elucidation of the biosynthetic pathways of these compounds is a prerequisite for metabolic engineering efforts that will improve production of these costly molecules. however, despite the medical and commercial importance of these natural products, the biosynthetic ...201020956330
clustered transcription factor genes regulate nicotine biosynthesis in tobacco.tobacco (nicotiana tabacum) synthesizes nicotine and related pyridine alkaloids in the root, and their synthesis increases upon herbivory on the leaf via a jasmonate-mediated signaling cascade. regulatory nic loci that positively regulate nicotine biosynthesis have been genetically identified, and their mutant alleles have been used to breed low-nicotine tobacco varieties. here, we report that the nic2 locus, originally called locus b, comprises clustered transcription factor genes of an ethylen ...201020959558
efficacy of anthelmintic properties of medicinal plant extracts against haemonchus contortus.the development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. among these alternatives are several medicinal plants traditionally used as anthelmintics. this present work evaluated the efficacy of ethyl acetate, acetone, and methanol dried leaf and seed extracts of five medicinal plants were tested in vitro ovicidal and larvicidal activities on haemonchus contortus. the in vitro assay was based on egg hatch as ...201020980034
spatial organization of the vindoline biosynthetic pathway in catharanthus roseus.vindoline constitutes the main terpenoid indole alkaloid accumulated in leaves of catharanthus roseus, and four genes involved in its biosynthesis have been identified. however, the spatial organization of the tabersonine-to-vindoline biosynthetic pathway is still incomplete. to pursue the characterization of this six-step conversion, we illustrated, with in situ hybridization, that the transcripts of the second biosynthetic enzyme, 16-hydroxytabersonine 16-o-methyltransferase (16omt), are speci ...201021047699
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