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directed biosynthesis of alkaloid analogs in the medicinal plant catharanthus roseus.terpene indole alkaloids are plant natural products with diverse structures and biological activities. a highly branched biosynthetic pathway is responsible for the production of approximately 130 different alkaloids in madagascar periwinkle (c. roseus) from a common biosynthetic intermediate derived from tryptamine. although numerous biosynthetic pathways can incorporate unnatural starting materials to yield novel natural products, it was not clear how efficiently the complex, eukaryotic tia pa ...200617076499
determination of biomass composition of catharanthus roseus hairy roots for metabolic flux analysis.metabolic flux analysis is a powerful diagnostic tool in metabolic engineering, and determination of biomass composition is indispensable to accurate flux evaluation. we report the elemental and biomolecular composition of catharanthus roseus hairy roots, a pharmaceutically significant plant system and an important metabolic engineering target. the molecular formula of the organic material in the hairy roots was c12.0h22.7n0.4o7.6 during mid-exponential growth. the abundances of lipids, lignin, ...200617137315
screening of herbal extracts for activation of the human peroxisome proliferator-activated receptor.the peroxisome proliferator-activated receptors play a pivotal role in metazoan lipid and glucose homeostasis. synthetic activators of pparalpha (fibrates) and ppargamma (glitazones) are therefore widely used for treatment of dislipidemia and diabetes, respectively. there is growing evidence for herbal compounds to influence nuclear receptor signalling e.g. the ppars. we recently reported carnosic acid and carnosol, both being diterpenes found in the labiate herbs sage and rosemary, to be activa ...200617152989
transcription factor agamous-like 12 from arabidopsis promotes tissue-like organization and alkaloid biosynthesis in catharanthus roseus suspension cells.in catharanthus roseus, monomeric terpenoid indole alkaloids (tias) are biosynthesized in specific tissues, particularly in roots, but failed to be produced by in vitro undifferentiated suspension cells. in this paper, we describe the impact of the root-specific mads-box transcription factor agamous-like 12 (agl12) from arabidopsis thaliana on the differentiation of suspension cells from c. roseus. the expression of agl12 is sufficient to promote an organization of suspension cells into globular ...200717157545
[determination of three endogenous hormones in catharanthus roseus (l.) g. don using solid-phase extraction and high performance liquid chromatography]. 200617165557
catharanthus roseus flower extract has wound-healing activity in sprague dawley rats.catharanthus roseus l (c. roseus) has been used to treat a wide assortment of diseases including diabetes. the objective of our study was to evaluate the antimicrobial and wound healing activity of the flower extract of catharanthus in rats.200617184528
involvement of rapid nucleotide synthesis in recovery from phosphate starvation of catharanthus roseus cells.growth of suspension-cultured catharanthus roseus cells ceased during phosphate starvation, but the cells grew again upon addition of pi even after long-term starvation. the metabolic fate of [(33)p]pi was studied in 1-week-old stationary phase cells in ordinary culture and in 1- or 2-week-old pi-starved cells. immediately after administration, the most heavily labelled organic compounds are nucleotides, followed by sugar phosphates. two weeks pi starvation slowed down the speed of incorporation ...200717185741
effect of near-ultraviolet light on alkaloid production in multiple shoot cultures of catharanthus roseus. 199117226190
strategies for the genetic manipulation of alkaloid-producing pathways in plants.increasingly, as a result of recent biochemical work, there exists a realistic possibility of taking a molecular genetic approach to the manipulation of alkaloid-producing pathways in plant tissue cultures. in the pathways forming indole alkaloids in catharanthus roseus, tropane alkaloids in datura and hyoscyamus species, and nicotine in nicotiana species, recent studies have identified a number of key enzymes and at least some of the factors that regulate their levels of activity. such knowledg ...199117226220
effects of near-ultraviolet light on alkaloid production in catharanthus roseus plants.artificial near-ultraviolet light with a peak at 370 nm and the light of natural radiation with wavelengths between 290 and 380 nm stimulated the synthesis of dimeric indole alkaloids in intact plants of catharanthus roseus. the artificial light also specifically stimulated an in vitro fmn-mediated, non-enzymatic coupling of vindoline and catharanthine to synthesize an iminium intermediate, the in vivo precursor of dimeric alkaloid synthesis. these results suggest that near-ultraviolet light is ...199317230336
long-term effect of a pythium elicitor treatment on the growth and alkaloid production of catharanthus roseus cell suspensions.the treatment of a catharanthus roseus cell suspension culture with a low concentration of pythium elicitor stimulated the alkaloid production. when these pretreated cells were resuspended in a medium that did not contain the fungal extract, the positive effects of the treatment on alkaloid synthesis and excretion were lost and, moreover, the standard level of production was not recovered. a second treatment of these cells with pythium elicitor at day 5 of the second culture cycle greatly impair ...199417236032
analysis of several iridoid and indole precursors of terpenoid indole alkaloids with a single hplc run.an isocratic hplc system is described which allows the separation of the iridoid and indole precursors of terpenoid indole alkaloids, which are present in a single crude extract. the system consists of a column of lichrospher 60 rp select b 5 microm, 250 x 4 mm (merck) with an eluent of 1% formic acid-acetonitrile-trichloroacetic acid (100:10:0.25, v:v:w) at a flow of 1.2 ml/min. in the suspension cultures of catharanthus roseus secologanin and tryptophan were detected. in the cultures of tabern ...199617252445
rapid in vitro multiplication of plants from mature nodal explants of catharanthus roseus. 199817253257
effect of the engineered indole pathway on accumulation of phenolic compounds in catharanthus roseus hairy roots.catharanthus roseus has been well-known to contain indole alkaloids effective for treatment of diverse cancers. we examined the intracellular accumulation profiles of phenolic compounds in response to ectopic overexpression of tryptophan feedback-resistant anthranilate synthase holoenzyme (asalphabeta) in c. roseus hairy roots. among 13 phenolic compounds measured, 6 phenolic compounds were detected in late exponential phase asalphabeta hairy roots. uninduced and induced asalphabeta hairy roots ...201317256967
mass spectral evidence of the occurrence of vindoline in heterotrophic cultures of catharanthus roseus cells.vindoline concentrations in the leaves of 70 catharanthus roseus of 3 cultivars were analyzed by hplc, and 3 plants were selected for starting callus cultures on different media. when the initial calli were analyzed using a vindoline-specific ria, the assay suggested a vindoline content of about 10 (-5)% dry weight for one-third of the first 60 cultures examined. due to the unexpectedly high incidence of vindoline-positive calli, the screening programme was discontinued and efforts were concentr ...198917262331
quantitative determination of vinblastine in tissue cultures of catharanthus roseus by radioimmunoassay.a radioimmunoassay has been developed for the quantitative determination of small amounts of vinblastine in tissue cultures of catharanthus roseus (l.) g. don. antibody was obtained by the immunization of rabbits against a conjugate of vinblastine with bovine serum albumin. the antibody had a high affinity (ka = 1.2 x 10 (9)l/mol) and specificity for vinblastine. the usable range of standard curve for assay was 0.5-10 ng/ml. crude alkaloid extracts of tissue cultures could be assayed and many sa ...198917262413
homogeneous strictosidine synthase isoenzymes from cell suspension cultures of catharanthus roseus.four separable isoforms of strictosidine synthase, which catalyze condensation of tryptamine with secologanin to form strictosidine, were purified to homogeneity from cultured cells of catharanthus roseus and from leaves of c. roseus plants. these enzymes are distinguished by their isoelectric points as well as by their catalytic properties. the specific activity of the main form (isoform iii) is 104 nkat/mg, k (cat) = 3.2 s (-1). the relative molecular mass is 31 kda as estimated by gel filtrat ...198917262473
stimulation of indole alkaloid content in vanadium-treated catharanthus roseus suspension cultures.addition of vanadyl sulphate to cell suspensions of catharanthus roseus was found to increase ajmalicine, catharanthine, and tryptamine levels. up to 500 microg/g dry weight catharanthine and 131.0 microg/g dry weight ajmalicine were detected in vanadyl sulphate-treated cells. this represents an approximate increase of 50% over control levels. this stimulation was found to be dependent upon the concentration of vanadyl sulphate administered and upon the cell age. high tryptamine levels were not ...198817265225
resistance to pythium aphanidermatum in diploids and induced autotetraploids of catharanthus roseus.resistance to pythium aphanidermatum (which causes die-back and collar and root rot) in seven diploid and four induced autotetraploid lines of catharanthus roseus was studied in the field during 1983 to 1985. the tetraploid lines were, depending on the year of evaluation, about 13 to 155, 18 to 218, and 17 to 366 times more resistant than diploid lines, when resistance was measured in terms of plant mortality, infection rate, and area under disease curve, respectively. on an average over three y ...198817265286
time-course studies in indole alkaloid accumulation and changes in tryptophan decarboxylase and strictosidine synthase activities: a comparison in three strains of catharanthus roseus cells.three different strains of catharanthus roseus cells were compared during one subculture with regard to tryptophan, tryptamine, ajmalicine, serpentine contents and tryptophane decarboxylase (tdc) (4) and strictosidine synthase activities. the strains differed greatly in their accumulation of tryptamine and alkaloid. the tdc of all three strains showed the highest activity during the growth phase and declined sharply at the end of this phase. on the contrary, strictosidine synthase activity was t ...198717269044
ajmalicine, serpentine, and catharanthine accumulation in catharanthus roseus bioreactor cultures.a 141, stirred-tank bioreactor was used to investigate the effect of 7% glucose solutions on catharanthus roseus suspension cultures. measurement of oxygen uptake rate indicated that alkaloid accumulation occurred primarily during a 20-day transition period between growth-oriented metabolism and maintenance-oriented metabolism. exposure of the cells to light during this period stimulated catharanthine accumulation and triggered a switch from ajmalicine accumulation to serpentine accumulation. in ...198717269046
stimulation of indole alkaloid production in cell suspension cultures of catharanthus roseus by abscisic acid.when added to suspension cultures of catharanthus roseus, abscisic acid (aba) stimulated intracellular accumulation of the indole alkaloids catharanthine and ajmalicine in both flask and 30 litre fermenter-scale systems. the response varied, and depended upon the cell line, the concentration and source of the aba, and the growth phase at which the cells were treated. precise timing of aba addition to cells in a 301 fermenter resulted in a catharanthine yield of 85.25 mg/l after 10 days of cultiv ...198717269070
alkaloid production in root and shoot cultures of catharanthus roseus.root and shoot cultures were induced from seedlings of catharanthus roseus. root cultures and cell suspension cultures derived from the root cultures showed similar alkaloid spectra to the roots of intact plants. the alkaloid spectra of shoot cultures and the aerial parts of intact plants were similar to each other but different from those of root and suspension cultures. illumination affected the alkaloid spectra of shoot cultures. shoot cultures produced 3',4'anhydrovinblastine, an immediate p ...198717269072
cloning, characterization and localization of a novel basic peroxidase gene from catharanthus roseus.catharanthus roseus (l.) g. don produces a number of biologically active terpenoid indole alkaloids via a complex terpenoid indole alkaloid biosynthetic pathway. the final dimerization step of this pathway, leading to the synthesis of a dimeric alkaloid, vinblastine, was demonstrated to be catalyzed by a basic peroxidase. however, reports of the gene encoding this enzyme are scarce for c. roseus. we report here for the first time the cloning, characterization and localization of a novel basic pe ...200717298442
promoter analysis of the catharanthus roseus geraniol 10-hydroxylase gene involved in terpenoid indole alkaloid biosynthesis.geraniol 10-hydroxylase (g10h) is an important enzyme in the biosynthetic pathway of monoterpenoid alkaloids found in diverse plant species. the catharanthus roseus g10h controls the first committed step in biosynthesis of terpenoid indole alkaloids (tia). the c. roseus g10h promoter sequence was isolated by a pcr-based genome walking method. sequence analysis revealed that the g10h promoter contains several potential eukaryotic regulatory elements involved in regulation of gene expression. the ...200717321612
effect of indole-3-butyric acid on phytoplasmas in infected catharanthus roseus shoots grown in vitro.phytoplasmas are noncultivable bacteria usually maintained in catharanthus roseus shoots grown in vitro on ms medium with benzylaminopurine. the aim of our research was to examine the influence of indole-3-butyric acid (iba) on c. roseus shoots infected with three different phytoplasma strains. supplement of iba in the medium supported plant growth, photosynthesis and remission of symptoms in all phytoplasma-infected shoots, but had no effect on the presence of ey-c and sa-i phytoplasma strains ...200717328744
transcript profiling of terpenoid indole alkaloid pathway genes and regulators reveals strong expression of repressors in catharanthus roseus cell cultures.the understanding of the complexities and molecular events regulating genes and the activators involved in terpenoid indole alkaloid (tia) metabolism is known to a certain extent in cell cultures of an important tia yielding plant, catharanthus roseus, though it is not yet complete. recently, the repressors of early tia pathway genes have also been identified. however, their roles in the regulation of tia pathway in c. roseus cell cultures remains yet unknown. we have made a comparative profilin ...200717333024
indole alkaloids from catharanthus roseus tissue cultures iv1: 16r-19,20-e-isositsirikin, 16r-19,20-z-isositsirikin and 21-hydroxycyclolochnerin.from catharanthus roseus cell suspension cultures 16 r-19,20- e-isositsirikine ( 1), 16 r-19,20- z-isositsirikine ( 2) and a new sarpagine type indole alkaloid ( 5) have been isolated. the structures have been deduced from spectroscopic data; that of 5 has been confirmed by x-ray analysis.198417340304
n-deformyl vincristine a bisalkaloid from catharanthus roseus.a bisalkaloid from catharanthus roseus is n-deformyl vincristine (ndf). its structure was clarified by spectroscopic methods.198417340313
instability of indole alkaloid production in catharanthus roseus cell suspension cultures.using serpentine fluorescence as an indicator of alkaloid production in cultured catharanthus roseus cells, 6 cell lines producing alkaloid in excess of 300 mg/l were selected from more than 2 x 10 (5) individual colonies and their alkaloid production was monitored over a period of 8 years. rapid loss of productivity invariably occurred during the first few months of cultivation, and spontaneous recovery of the initial production rates was never observed. production of the indole alkaloid precur ...198417340345
influence of sucrose on levels of ajmalicine, serpentine, and tryptamine in catharanthus roseus cells in vitro.the fates of major nutritional elements and the synthesis of tryptophan, tryptamine and 2 alkaloid markers in c. roseus cells, cultivated in media containing 20 and 60 g/l of sucrose, were studied. sucrose effects were greatest, with these parameters, during the stationary growth phase. intracellular ajmalicine and serpentine levels increased with sucrose concentration, whereas intracellular tryptamine (nitrogen precursor) levels were unaffected. the role of sucrose in the alkaloid pathway is di ...198417340363
evaluation of endophytic colonization of citrus sinensis and catharanthus roseus seedlings by endophytic bacteria.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 appro ...200717342049
isolation and 13c-nmr studies on cathovaline, an alkaloid from the leaves of catharanthus roseus.studies on the alkaloidal constituents of the leaves of catharanthus roseus have resulted in the isolation of cathovaline. (13)c-nmr studies have been carried out on the alkaloid using adept and apt pulse sequences. cathovaline has not been previously reported from this plant but has been isolated from the roots of catharanthus lanceus (boj. ex. a. de) pich (1) and catharanthus ovalis markgraf, sp. nov. (2).198517342609
geraniol-10-hydroxylase of catharanthus roseus and its correlation with indole alkaloid biosynthesis. 198617345379
ethnomedicines used in trinidad and tobago for reproductive problems.throughout history women have tried to control or enhance their fertility using herbal remedies, with various levels of societal support. caribbean folk medicine has been influenced by european folk medicine, either through the early spanish and french settlers or through the continuous immigration of spanish-speaking peoples from venezuela. some folk uses are ancient and were documented by galen and pliny the elder.200717362507
initiation, maintenance and alkaloid content of catharanthus roseus leaf organ cultures. 198217396784
immobilization of strictosidine synthase from catharanthus cell cultures and preparative synthesis of strictosidine.strictosidine synthase was partially purified from catharanthus roseus cell suspension cultures and immobilized on cnbr-activated sepharose. the immobilized enzyme exhibits a thermostability increased 300 fold over that of the soluble enzyme and catalyses exclusively the formation of the 3alpha(s)-isomer, strictosidine. gram quantities of this biologically active glucoalkaloid, which hitherto had been difficult to synthesize and purify, were prepared.198217396930
alkaloid production in catharanthus roseus cell cultures viii.a cell line of catharanthus roseus (l.) g. don coded prl # 200, was characterized with respect to its biosynthetic capabilities for indolealkaloids, in particular catharanthine, in suspension cultures. other alkaloids isolated are vallesiachotamine isomers, ajmalicine, hörhammericine, hörhammerinine, vindolinine, 19-epivindolinine and strictosidine lactam.198117401876
efficient incorporation of 10-hydroxygeraniol and 10-hydroxynerol into indole alkaloids by a cell suspension culture of catharanthus roseus.a cell suspension culture of catharanthus roseus was evaluated with regard to its potential usage in studies of early stage indole alkaloid biosynthesis. employing this material, 1,1,7-trideutero-10-hydroxygeraniol and 1,1,7-trideutero-10-hydroxynerol were incorporated into the alkaloids ajmalicine and strictosidine lactam in approximate proportions of 50% and 80% respectively.198217402127
[time course of growth, evolution of sugar-nitrogen metabolism and accumulation of alkaloids in a cell suspension of catharanthus roseus.].intra and extra-cellular accumulation of three alkaloid markers, the disappearance of major nutrients from the medium and the evolution of phosphates, nitrates, ammonium ions, glucose and starch in the cells were observed during a time course study using a suspension of catharanthus roseus. the accumulation of alkaloids is a complex phenomenon, not entirely unconnected with growth, which involves diffusion into the medium and cellular catabolism. it is difficult to relate the phenomenon to the a ...198317404908
[quantitative and qualitative hplc-analysis of indole alkaloids from catharanthus roseus cell cultures.].hplc separation conditions for the qualitative and quantitative analysis of indole alkaloids from catharanthus roseus tissue cultures were discribed as well as sample preparation procedures with extrelut and bond elut scx cartridges, which allow a quicker and more effective sample clean up as the classical alkaline chloroform extraction method. the methods are suitable for very small amounts of cell material.198317404909
indole alkaloid formation and storage in cell suspension cultures of catharanthus roseus.the localization and storage of alkaloids were investigated in a low producing cell suspension culture of catharanthus roseus(l.) g. don. (apocynaceae). fluorescence microscopy and electron microscopy indicate alkaloid accumulation to occur inside the vacuoles of particular cells. these alkaloid storage cells exhibit a vacuolar ph of 3, while "normal" cells of a suspension culture have a vacuolar ph of about 5. alkaloids are taken up in their unprotonated forms, trapped by protonation inside the ...198317404935
the role of 9- and/or 10-oxygenated derivatives of geraniol, geranial, nerol, and neral in the biosynthesis of loganin and ajmalicine.a number of deuterium labelled 9- and/or 10-oxygenated derivatives of geraniol, geranial, nerol, and neral were used as substrates in feeding experiments with a cell suspension culture of catharanthus roseus. the 9- and 10-oxo derivatives of geraniol, geranial, nerol, and neral as well as 9,10-dihydroxygeraniol, 9-oxo-10-hydroxygeraniol, and 9,9,10,10-tetraethoxygeranial were found to be good precursors of the indole alkaloid ajmalicine. the compounds 9-hydroxygeraniol, 9-hydroxynerol, 9,10-dihy ...198317405022
isolation of new alkaloids from catharanthus roseus. 198317405031
enhancing terpenoid indole alkaloid production by inducible expression of mammalian bax in catharanthus roseus cells.bax, a mammalian pro-apoptotic member of the bcl-2 family, triggers hypersensitive reactions when expressed in plants. to investigate the effects of bax on the biosynthesis of clinically important natural products in plant cells, we generate transgenic catharanthus roseus cells overexpressing a mouse bax protein under the beta-estradiol-inducible promoter. the expression of bax in transgenic catharanthus roseus cells is highly dependent on beta-estradiol concentrations applied. contents of catha ...200717447031
glycosylation of capsaicin and 8-nordihydrocapsaicin by cultured cells of catharanthus roseus.the glycosylation of capsaicin and 8-nordihydrocapsaicin was investigated using cultured cells of catharanthus roseus. in addition to capsaicin 4-o-beta-d-glucopyranoside (170 microg/g fr. wt of cells), the biotransformation products, capsaicin 4-o-(6-o-beta-d-xylopyranosyl)-beta-d-glucopyranoside (116 microg/g fr. wt of cells) and capsaicin 4-o-(6-o-alpha-l-arabinopyranosyl)-beta-d-glucopyranoside (83 microg/g fr. wt of cells), were isolated from the cell suspension after three days of incubati ...200717449077
identification of a bipartite jasmonate-responsive promoter element in the catharanthus roseus orca3 transcription factor gene that interacts specifically with at-hook dna-binding proteins.jasmonates are plant signaling molecules that play key roles in defense against certain pathogens and insects, among others, by controlling the biosynthesis of protective secondary metabolites. in catharanthus roseus, the apetala2-domain transcription factor orca3 is involved in the jasmonate-responsive activation of terpenoid indole alkaloid biosynthetic genes. orca3 gene expression is itself induced by jasmonate. by loss- and gain-of-function experiments, we located a 74-bp region within the o ...200717496112
an efficient chemoenzymatic production of small molecule glucosides with in situ udp-glucose recycling.a one-pot system for efficient enzymatic synthesis of curcumin glucosides is described. the method couples the activities of two recombinant enzymes, udp-glucose: curcumin glucosyltransferase from catharanthus roseus (caugt2) and sucrose synthase from arabidopsis thaliana (atsus1). udp, a product inhibitor of udp-glucosyltransferase, was removed from the system and used for regeneration of udp-glucose by the second enzyme, atsus1. the productivity was increased several-fold and udp-glucose initi ...200717499718
a single amino acid in the pspg-box plays an important role in the catalytic function of caugt2 (curcumin glucosyltransferase), a group d family 1 glucosyltransferase from catharanthus roseus.curcumin glucosyltransferase (caugt2) isolated from cell cultures of catharanthus roseus exhibits unique substrate specificity. to identify amino acids involved in substrate recognition and catalytic activity of caugt2, a combination of domain swapping and site-directed mutagenesis was carried out. exchange of the pspg-box of caugt2 with that of ntgt1b (a phenolic glucosyltransferase from tobacco) led to complete loss of enzyme activity in the resulting recombinant protein. however, replacement ...200717509574
flux quantification in central carbon metabolism of catharanthus roseus hairy roots by 13c labeling and comprehensive bondomer balancing.methods for accurate and efficient quantification of metabolic fluxes are desirable in plant metabolic engineering and systems biology. toward this objective, we introduce the application of "bondomers", a computationally efficient and intuitively appealing alternative to the commonly used isotopomer concept, to flux evaluation in plants, by using catharanthus roseus hairy roots as a model system. we cultured the hairy roots on (5% w/w u-(13)c, 95% w/w naturally abundant) sucrose, and acquired t ...200717532015
molecular cloning and characterization of crmdr1, a novel mdr-type abc transporter gene from catharanthus roseus.a novel gene encoding a mdr-like abc transporter protein was cloned from catharanthus roseus, a medicinal plant with more than 120 kinds of secondary metabolites, through rapid amplification of cdna ends (race). this gene (named as crmdr1; genbank accession no.: dq660356) had a total length of 4395 bp with an open reading frame of 3801 bp, and encoded a predicted polypeptide of 1266 amino acids with a molecular weight of 137.1 kda. the crmdr1 protein shared 59.8, 62.5, 60.0 and 58.2% identity wi ...200717541839
responses of transformed catharanthus roseus roots to femtomolar concentrations of salicylic acid.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 affe ...201617544287
rapid and non-invasive detection of plants senescence using a delayed fluorescence technique.senescence is a phase of leaf ontogeny marked by declining photosynthetic activity that is paralleled by a decline in chloroplast function. the photosystem ii in a plant is considered to be the primary site where delayed fluorescence (df) is produced. we report here a simple, rapid, and non-invasive technique for detecting plants senescence based on quantitative measurements of df. in the experimental study, various senescence symptoms induced by age or hormones were examined in the catharanthus ...200717549265
dynamic flux cartography of hairy roots primary metabolism.a dynamic model for plant cell and hairy root primary metabolism is presented. the model includes nutrient uptake (pi, sugars, nitrogen sources), the glycolysis and pentose phosphate pathways, the tca cycle, amino acid biosynthesis, respiratory chain, biosynthesis of cell building blocks (structural hexoses, organic acids, lipids, and organic phosphated molecules). the energy shuttles (atp, adp) and cofactors (nad/h, nadp/h) are also included. the model describes the kinetics of 44 biochemical r ...201317555780
alterations in osmoregulation, antioxidant enzymes and indole alkaloid levels in catharanthus roseus exposed to water deficit.catharanthus roseus (l.) g. don plants were grown in different water regimes in order to study the drought induced osmotic stress and proline (pro) metabolism, antioxidative enzyme activities and indole alkaloid accumulation. the plants under pot culture were subjected to 10, 15 and 20 days interval drought (did) stress from 30 days after sowing (das) and regular irrigation was kept as control. the plants were uprooted on 41das (10did), 46das (15did) and 51das (20did). the drought stressed plant ...200717560094
expression of deacetylvindoline-4-o-acetyltransferase in catharanthus roseus hairy roots.madagascar periwinkle [catharanthus roseus (l.) g don] is a pantropical plant of horticultural value that produces the powerful anticancer drugs vinblastine and vincristine that are derived from the dimerization of the monoterpenoid indole alkaloids (mias), vindoline and catharanthine. the present study describes the genetic engineering and expression of the terminal step of vindoline biosynthesis, deacetylvindoline-4-o-acetyltransferase (dat) in catharanthus roseus hairy root cultures. biochemi ...200717574634
alterations in seedling vigour and antioxidant enzyme activities in catharanthus roseus under seed priming with native diazotrophs.an experiment was conducted on catharanthus roseus to study the effect of seed treatments with native diazotrophs on its seedling growth and antioxidant enzyme activities. the treatments had significant influence on various seedling parameters. there is no significant influence on dry matter production with the diazotrophs, azospirillum and azotobacter. however, the vital seedling parameters such as germination percentage and vigour index were improved. azotobacter treatment influenced maximum o ...200717610323
spatial distribution and hormonal regulation of gene products from methyl erythritol phosphate and monoterpene-secoiridoid pathways in catharanthus roseus.the monoterpene indole alkaloids (mias) from madagascar periwinkle (catharanthus roseus) are secondary metabolites of high interest due to their therapeutical values. secologanin, the monoterpenoid moiety incorporated into mias, is derived from the plastidial methyl-d: -erythritol 4-phosphate (mep) pathway. here, we have cloned a cdna encoding hydroxymethylbutenyl diphosphate synthase (hds), a mep pathway enzyme, and generated antibodies to investigate the distribution of transcripts and protein ...200717611800
a predictive nutritional model for plant cells and hairy roots.a structured nutritional model is proposed to describe growth and nutritional behavior of eschscholtzia californica suspension cells and catharanthus roseus and daucus carota hairy roots in in vitro culture. the model describes the cells specific growth rate from concentration of intracellular nutrients such as inorganic phosphate (pi), nitrogen sources (no(3) (-) and nh(4) (+)) and sugars. two-level michaelis-menten kinetics are used to describe pi and no(3) (-) uptake and simple michaelis-ment ...200817614323
downregulation of terpenoid indole alkaloid biosynthetic pathway by low temperature and cloning of a ap2 type c-repeat binding factor (cbf) from catharanthus roseus (l). g. don.plants produce secondary metabolites in response to various external signals. coordinated transcriptional control of biosynthetic genes emerges as a major mechanism dictating the accumulation of secondary metabolites in plant cells. however, information about stress regulation of secondary metabolites and the molecular mechanisms regulating these specialized pathways are poorly understood. here, we show that terpenoid indole alkaloid (tia) biosynthetic pathway is differentially regulated in resp ...200717619193
water deficit stress mitigation by calcium chloride in catharanthus roseus: effects on oxidative stress, proline metabolism and indole alkaloid accumulation.the present investigation was conducted to determine whether cacl(2) increases catharanthus roseus drought tolerance and if such tolerance is correlated with changes in oxidative stress, osmoregulation and indole alkaloid accumulation. c. roseus plants were grown under water deficit environments with or without cacl(2). drought induced oxidative stress was measured in terms of lipid peroxidation (lpo) and h(2)o(2) contents, osmolyte concentration, proline (pro) metabolizing enzymes and indole al ...200717643271
antioxidant potentials and ajmalicine accumulation in catharanthus roseus after treatment with giberellic acid.changes in antioxidant potentials and indole alkaloid, ajmalicine, production were studied in catharanthus roseus (l.) g. don. plants under treatment with gibberellic acid (ga(3)). the ga(3) treatments were given in two ways, foliar spray and soil drenching methods on 30, 45, 60 and 75 days after planting (dap). the plants were uprooted randomly on 90 dap and separated into root, stem and leaves and used for analyses. the antioxidant potential was studied in terms of non-enzymatc antioxidant mol ...200717643272
induction of drought stress tolerance by ketoconazole in catharanthus roseus is mediated by enhanced antioxidant potentials and secondary metabolite accumulation.a pot culture experiment was conducted to estimate the drought stress mitigating effect of ketoconazole (kcz), a fungicide cum plant growth regulator, in catharanthus roseus plants. the plants under pot culture were subjected to drought stress and drought stress with kcz from 30 days after sowing (das) and regular irrigation was kept as control. antioxidant contents and activities of antioxidant enzymes were estimated from root, stem and leaf of both control and treated plants. the alkaloid ajma ...200717643970
membrane-associated phosphoinositides-specific phospholipase c forms from catharanthus roseus transformed roots.we have previously reported that catharanthus roseus transformed roots contain at least two phosphatidylinositol 4,5-bisphosphate-phospholipase c (plc) activities, one soluble and the other membrane associated. detergent, divalent cations, and neomycin differentially regulate these activities and pure protein is required for a greater understanding of the function and regulation of this enzyme. in this article we report a partia purification of membrane-associated plc. we found that there are at ...200717652793
optimisation of supercritical fluid extraction of indole alkaloids from catharanthus roseus using experimental design methodology--comparison with other extraction techniques.response surface modelling, using modde 6 software for design of experiments and optimisation, was applied to optimise supercritical fluid extraction (sfe) conditions for the extraction of indole alkaloids from the dried leaves of catharanthus roseus. the effects of pressure (200-400 bar), temperature (40-80 degrees c), modifier concentration (2.2-6.6 vol%) and dynamic extraction time (20-60 min) on the yield of alkaloids were evaluated. the extracts were analysed by high-performance liquid chro ...201517654538
allergy to periwinkle pollen (catharanthus roseus g. don.).catharanthus roseus g. don. (cr) or periwinkle plants are widely grown/ cultivated as garden plants in the tropics and subtropics. in spite of its predominantly entomophilous nature, cr pollen had been reported to be airborne and allergenic. the objective of this study was to discover the seasonal changes of cr pollen concentration in air, to determine its potential to cause respiratory allergy and to analyze its allergenic components. a 2-year aerobiological survey was conducted with a burkard ...200717655175
pseudomonas fluorescens enhances biomass yield and ajmalicine production in catharanthus roseus under water deficit stress.the effect of plant growth promoting rhizobacteria (pgpr) like pseudomonas fluorescens on growth parameters and the production of ajmalicine were investigated in catharanthus roseus under drought stress. the plants under pot culture were subjected to 10, 15 and 20 days interval drought (did) stress and drought stress with pseudomonas fluorescens at 1mgl(-1) and 1mgl(-1)pseudomonas fluorescens alone from 30 days after planting (dap) and regular irrigation was kept as control. the plants were upro ...200717681765
evaluation of wound-healing potential of catharanthus roseus leaf extract in rats.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.200717683880
hypoglycemic effect of catharanthus roseus in normal and streptozotocin-induced diabetic rats.the effects of crude juice (at 0.5 and 1 ml/kg b.w.) and aqueous extract (at 0.30 and 0.45 gm/kg b.w.) of leaves of catharanthus roseus on serum glucose level in streptozotocin induced diabetic rats were examined at 8 hours, 12 hours and 24 hours following single oral administration. the administration of crude juice at 1 ml/kg b.w. continued for another 9 doses (total 10 single morning doses given) and its effect was examined on the 4th and 11th day. the rats were made diabetic by single intrap ...200717703149
characterization of an ethanol-inducible promoter system in catharanthus roseus hairy roots.efforts to engineer catharanthus roseus hairy roots to produce commercially significant amounts of valuable compounds, such as the terpenoid indole alkaloids vinblastine and vincristine, require the development of tools to study the effects of overexpressing key metabolic and regulatory genes. the use of inducible promoters allows researchers to control the timing and level of expression of genes of interest. in addition, use of inducible promoters allows researchers to use a single transgenic l ...200717715939
rapid identification of enzyme variants for reengineered alkaloid biosynthesis in periwinkle.monoterpene indole alkaloids from catharanthus roseus (madagascar periwinkle), such as the anticancer agents vinblastine and vincristine, have important pharmacological activities. metabolic engineering of alkaloid biosynthesis can provide an efficient and environmentally friendly route to analogs of these synthetically challenging and pharmaceutically valuable natural products. however, the narrow substrate scope of strictosidine synthase, the enzyme at the entry point of the pathway, limits a ...200717719488
calcium chloride effects on salinity-induced oxidative stress, proline metabolism and indole alkaloid accumulation in catharanthus roseus.catharanthus roseus (l.) g. don. plants were grown with nacl and cacl2 in order to study the effect of cacl2 on nacl-induced oxidative stress in terms of lipid peroxidation (tbars content), h2o2 content, osmolyte concentration, proline (pro)-metabolizing enzymes, antioxidant enzyme activities, and indole alkaloid accumulation. the plants were treated with solutions of 80 mm nacl, 80 mm nacl with 5 mm cacl2 and 5 mm cacl2 alone. groundwater was used for irrigation of control plants. plants were u ...200717720584
diffusible factors essential for epidermal cell redifferentiaion in catharanthus roseus.during postgenital tissue fusions, some plant epidermal cells redifferentiate into parenchyma, a different cell type. diffusible factors cause this response in the fusing gynoecium of the madagascar periwinkle (catharanthus roseus). surgical manipulations of the gynoecium showed that epidermal cells from normally nonfusing surfaces could trasmit and respond to the diffusible factors. furthermore, the diffusible fators could be trapped in agar-impregnated barriers, as shown by the redifferentiati ...198917769401
long-term maintenance of a transgenic catharanthus roseus hairy root line.stably transformed transgenic hairy root cultures have the potential to be a valuable production platform for a variety of secondary metabolites. this study reports that a transgenic hairy root culture of catharanthus roseus has been stably maintained for over 4.5 years. this culture carries a transgene that expresses the green fluorescent protein under the control of the glucocorticoid-inducible promoter. genomic pcr confirmed the presence of the gfp insert within the hairy roots, and induction ...200717900137
a simplified procedure for indole alkaloid extraction from catharanthus roseus combined with a semi-synthetic production process for vinblastine.dried leaves of catharanthus roseus were extracted with aqueous acidic 0.1 m solution of hcl. alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (naoh) solution of embonic acid (4,4-methylene-bis-3-hydroxynaphtalenecarboxylic acid). the precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi-synthesis of the anti-cancer bisindole alkaloid vinblastine. the coupling reaction i ...200717909486
involvement of nitric oxide signaling in mammalian bax-induced terpenoid indole alkaloid production of catharanthus roseus cells.bax, a mammalian pro-apoptotic member of the bcl-2 family, has been demonstrated to be a potential regulatory factor for plant secondary metabolite biosynthesis recently. to investigate the molecular mechanism of bax-induced secondary metabolite biosynthesis, we determined the contents of nitric oxide (no) of the transgenic catharanthus roseus cells overexpressing a mouse bax protein and checked the effects of no specific scavenger 2,4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide ...200717914641
purification and characterization of udp-glucose : curcumin glucoside 1,6-glucosyltransferase from catharanthus roseus cell suspension cultures.catharanthus roseus cell suspension cultures converted exogenously added curcumin to a series of curcumin glucosides that possessed drastically enhanced water solubility. a cdna clone encoding a glucosyltransferase responsible for glucosylation of curcumin to form curcumin 4'-o-glucoside was previously isolated, and in the present study a novel sugar-sugar glycosyltransferase, udp-glucose:curcumin glucoside glucosyltransferase (ucggt), was purified approximately 900-fold to apparent homogeneity ...200717940060
alterations in morphological parameters and photosynthetic pigment responses of catharanthus roseus under soil water deficits.an experiment was conducted in two varieties, rosea and alba, of catharanthus roseus plants with two watering treatments viz., 100 and 60% of field capacity, to understand the effects of water deficit on early growth, biomass allocation and photosynthetic pigment responses. we found that there were significant differences in early growth, dry matter accumulation and pigment variations between the two varieties. the root length, shoot length, total leaf area, fresh and dry weights were significan ...200817949951
studies on rhizosphere microbial diversity of some commercially important medicinal plants.a preliminary study was made on four medicinal plants viz., ocimum sanctum l., coleus forskholii briq, catharanthus roseus (l.) g. don. and aloe vera in order to identify and enumerate the rhizosphere, non-rhizosphere and diazotrophic microorganisms in soil. the diazotrophic bacterial population studied includes azospirillum, azotobacter and pseudomonas. the rhizosphere bacterial populations were 23.33 x 10(6)g(-1) in o. sanctum followed by c. roseus (20.46 x 10(6)g(-1)), a. vera (18.44 x 10(6)g ...200817951032
[simultaneous determination of vindoline, catharanthine and anhydrovinblastine in catharanthus roseus by high performance liquid chromatography].a high performance liquid chromatographic (hplc) method with gradient elution was developed for the simultaneous determination of vindoline, catharanthine and anhydrovinblastine in catharanthus roseus. the analytes were separated on a waters (5)c18-ms-ii column (4.6 mm x 250 mm) and detected at 220 nm. the mobile phases were methanol-1% (v/v) diethylamine solution (adjusted to ph 7.3 with phosphate) for gradient elution at temperature of 25 degrees c. the calibration curves for vindoline, cathar ...200717970117
the endophyte curtobacterium flaccumfaciens reduces symptoms caused by xylella fastidiosa in catharanthus roseus.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 cv ...200717978797
uv-b-induced signaling events leading to enhanced-production of catharanthine in catharanthus roseus cell suspension cultures.elicitations are considered to be an important strategy towards improved in vitro production of secondary metabolites. in cell cultures, biotic and abiotic elicitors have effectively stimulated the production of plant secondary metabolites. however, molecular basis of elicitor-signaling cascades leading to increased production of secondary metabolites of plant cell is largely unknown. exposure of catharanthus roseus cell suspension culture to low dose of uv-b irradiation was found to increase th ...200717988378
water deficit stress effects on reactive oxygen metabolism in catharanthus roseus; impacts on ajmalicine accumulation.in the present work, we have analysed the changes in the reactive oxygen metabolism of catharanthus roseus (l.) g. don. plants in terms of h(2)o(2) content, lipid peroxidation and the free radical quenching systems (non-enzymatic and enzymatic antioxidants) under drought stress. in addition to this, the root alkaloid ajmalicine was extracted and quantified from both control and drought stressed plants. the h(2)o(2) content was analysed from both stressed and unstressed control plants. lipid pero ...200817996429
application of carborundum abrasion for investigating the leaf epidermis: molecular cloning of catharanthus roseus 16-hydroxytabersonine-16-o-methyltransferase.the madagascar periwinkle (catharanthus roseus) produces the well-known and remarkably complex anti-cancer dimeric alkaloids vinblastine and vincristine that are derived from the coupling of vindoline and catharanthine monomers. this study describes the novel application of a carborundum abrasion (ca) technique for large-scale isolation of leaf epidermis-enriched proteins in order to purify to apparent homogeneity 16-hydroxytabersonine-16-o-methyltransferase (16omt), which catalyses the second o ...200818053006
substrate specificity and diastereoselectivity of strictosidine glucosidase, a key enzyme in monoterpene indole alkaloid biosynthesis.strictosidine glucosidase (sgd) from catharanthus roseus catalyzes the deglycosylation of strictosidine, an intermediate from which thousands of monoterpene indole alkaloids are derived. the steady-state kinetics of sgd with a variety of strictosidine analogs revealed the substrate preferences of this enzyme at two key positions of the strictosidine substrate. additionally, sgd from c. roseus turns over both strictosidine and its stereoisomer vincoside, indicating that although this enzyme prefe ...200818061449
molecular cloning and characterization of a vacuolar class iii peroxidase involved in the metabolism of anticancer alkaloids in catharanthus roseus.catharanthus roseus produces low levels of two dimeric terpenoid indole alkaloids, vinblastine and vincristine, which are widely used in cancer chemotherapy. the dimerization reaction leading to alpha-3',4'-anhydrovinblastine is a key regulatory step for the production of the anticancer alkaloids in planta and has potential application in the industrial production of two semisynthetic derivatives also used as anticancer drugs. in this work, we report the cloning, characterization, and subcellula ...200818065566
the suzuki-miyaura reaction in the chemical transformations of vindoline.vindoline and its analogues are important constituents of the madagascan periwinkle catharanthus roseus, and some of them are valuable chemotherapy drugs used in treatment for some types of cancer, including leukaemia, lymphoma, breast and lung cancer. the search for semi-synthetic congeners of natural substances is still an important task for organic chemistry. in this communication we report the synthesis of five new vindoline derivatives, 15-(2-methoxyphenyl)vindoline 11, 15-(3-methoxyphenyl) ...200718066403
antioxidant potential and indole alkaloid profile variations with water deficits along different parts of two varieties of catharanthus roseus.the variations in antioxidant potentials and indole alkaloid content were studied in the present investigation, in two varieties (rosea and alba) of catharanthus roseus, an important herb used in traditional as well as modern medicine, exposed to water deficit stress. the antioxidant and alkaloid profiles were estimated from root, stem, leaf, flowers and pods. the antioxidant potentials were examined in terms of non-enzymatic antioxidant molecules and activities of antioxidant enzymes. the non-e ...200818068339
alterations in lipid peroxidation, electrolyte leakage, and proline metabolism in catharanthus roseus under treatment with triadimefon, a systemic fungicide.triadimefon (tdm), a systemic fungicide with non-traditional plant-growth regulator properties, was administered to catharanthus roseus (l.) g. don. plants in order to determine its effects on oxidative injury in terms of h2o2 content, lipid peroxidation (lpo), electrolyte leakage (el), protein and amino acid contents, as well as proline metabolism. the lpo, estimated as thiobarbituric acid-reactive substances (tbars), decreased under tdm treatment. it was found that h2o2 and el were reduced und ...200718068649
7-o-methylated anthocyanidin glycosides from catharanthus roseus.anthocyanins were isolated from orange-red flowers of catharanthus roseus cv 'equator deep apricot', and identified as rosinidin 3-o-[6-o-(alpha-rhamnopyranosyl)-beta-galactopyranoside] (1), and also 7-o-methylcyanidin 3-o-[6-o-(alpha-rhamnopyranosyl)-beta-galactopyranoside] (2) by chemical and spectroscopic methods. pigment 1 was found to be a major anthocyanin in the flowers of this cultivar. by contrast, the distribution of rosinidin glycosides is very limited in plants, and reported only in ...200818164044
differential responses in water use efficiency in two varieties of catharanthus roseus under drought stress.two varieties, rosea and alba, of catharanthus roseus (l.) g. don. were screened for their water use efficiency under two watering regimes, viz. 60 and 100% filed capacity in the present study. drought stress was imposed at 60% filed capacity from 30 to 70 days after sowing, while the control pots were maintained at 100% filed capacity throughout the entire growth period. leaf area duration, cumulative water transpired, water use efficiency, net assimilation rate, mean transpiration rate, harves ...200818187121
construction of genetic linkage map of the medicinal and ornamental plant catharanthus roseus.an integrated genetic linkage map of the medicinal and ornamental plant catharanthus roseus, based on different types of molecular and morphological markers was constructed, using a f(2) population of 144 plants. the map defines 14 linkage groups (lgs) and consists of 131 marker loci, including 125 molecular dna markers (76 rapd, 3 rapd combinations; 7 issr; 2 est-ssr from medicago truncatula and 37 other pcr based dna markers), selected from a total of 472 primers or primer pairs, and six morph ...200718305345
the leaf epidermome of catharanthus roseus reveals its biochemical specialization.catharanthus roseus is the sole commercial source of the monoterpenoid indole alkaloids (mias), vindoline and catharanthine, components of the commercially important anticancer dimers, vinblastine and vincristine. carborundum abrasion technique was used to extract leaf epidermis-enriched mrna, thus sampling the epidermome, or complement, of proteins expressed in the leaf epidermis. random sequencing of the derived cdna library established 3655 unique ests, composed of 1142 clusters and 2513 sing ...200818326827
inheritance of pollen-less anthers and "thrum" and "pin" flowers in periwinkle.two mutants, 1 with small, pollen-less anthers (or-ea) and another with "pin" flowers (ems 13-2), in contrast to "thrum" flowers found in normal periwinkle (catharanthus roseus) plants, were isolated after induced mutagenesis in strain or and cultivar, "dhawal," respectively. inheritance of these 2 traits, pollen-less anthers, and pin flowers was studied by crossing the mutants with their respective parental strains. segregation ratios observed in f(2) and testcross generations of the cross or-e ...200818339651
growth and photosynthetic pigments responses of two varieties of catharanthus roseus to triadimefon treatment.triadimefon, potential fungicide cum plant-growth retardant was used in this study to investigate its effect on the growth and the photosynthetic pigment contents of two varieties of catharanthus roseus (l.) g. don. the plants of both varieties were subjected to 15 mg l(-1) triadimefon treatment by soil drenching 30, 45, 60, and 75 days after planting (dap). plants were uprooted on 90 dap, and morphological parameters, like plant height, number of leaves, leaf area, root length and fresh and dry ...200818355749
impact of cadmium and lead on catharanthus roseus--a phytoremediation study.the madagascar periwinkle, catharanthus roseus (l.) g. don (a valued medicinal plant) was exposed to different concentrations ofheavymetals like, cdcl, and pbcl, with a view to observe their bioaccumulation efficiency. germination was inhibited by both the heavy metals in the seeds previously imbibed in ga, and kno, for 24 hr. ec50 (the effective concentration which inhibits root length by 50%) was recorded as 180 microm for cdcl2, and 50 microm for pbcl2. both alpha-amylase and protease activit ...200718380091
quantitative analysis of anionic metabolites for catharanthus roseus by capillary electrophoresis using sulfonated capillary coupled with electrospray ionization-tandem mass spectrometry.this paper describes a practical method to quantify anionic metabolites using contemporary capillary electrophoresis-electrospray ionization-tandem mass spectrometry (ce-esi-ms/ms). the use of sulfonated capillary permitted a simultaneous analysis of sugar phosphates, organic acids, nucleotides and coenzyme a compounds with only one ce condition. this capillary also improved the repeatability and sensitivity. ms/ms with multiple reaction monitoring (mrm) detection was utilized to achieve signifi ...200818397777
enhanced catharanthine and vindoline production in suspension cultures of catharanthus roseus by ultraviolet-b light.suspension cultures of catharanthus roseus were used to evaluate ultraviolet-b (uv-b) treatment as an abiotic elicitor of secondary metabolites. a dispersed cell suspension culture from c. roseus leaves in late exponential phase and stationary phase were irradiated with uv-b for 5 min. the stationary phase cultures were more responsive to uv-b irradiation than late exponential phase cultures. catharanthine and vindoline increased 3-fold and 12-fold, respectively, on treatment with a 5-min uv-b i ...200818439256
opium poppy and madagascar periwinkle: model non-model systems to investigate alkaloid biosynthesis in plants.alkaloids represent a large and diverse group of compounds that are related by the occurrence of a nitrogen atom within a heterocyclic backbone. unlike other types of secondary metabolites, the various structural categories of alkaloids are unrelated in terms of biosynthesis and evolution. although the biology of each group is unique, common patterns have become apparent. opium poppy (papaver somniferum), which produces several benzylisoquinoline alkaloids, and madagascar periwinkle (catharanthu ...200818476877
growth kinetics of dioscorea deltoidea and catharanthus roseus in batch culture.sugar-limited batch growth of dioscorea deltoidea and catharanthus roseus plant cell cultures was studied in a 14-l stirred tank fermentor. with dissolved oxygen concentration monitored and maintained at nonlimiting levels, growth rates and ratios of dry weight to fresh weight were found to be strongly influenced by sugar concentration. linear relationships between respiration rate and growth rate were observed, and respiration rate was found to drop to a maintenance level after sugar had been f ...198618553873
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