SEARCH · PubMed Health

Results for “HYOSCYAMUS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources

PubMed2005

Putrescine N-methyltransferase in Solanum tuberosum L., a calystegine-forming plant.

Putrescine N-methyltransferase (PMT, EC 2.1.1.53) catalyses the first specific step in the biosynthesis of tropane and nicotine alkaloids. Potato (Solanum tuberosum L.) contains neither nicotine nor the medicinal tropane alkaloids hyoscyamine or scopolamine, but calystegines. They are nortropane alkaloids with glycosidase inhibitory activity. Based on the assumption of calystegine formation by the tropane alkaloid pathway, PMT genes and enzymes were investigated in potato. Sprouting tubers contained both N-methylputrescine and PMT activity. Two cDNA clones coding for PMTs were obtained together with a cDNA clone for spermidine synthase (SPDS, EC 2.5.1.16). The pmt sequences resemble those from Nicotiana tabacum (85% identity) and those from tropane alkaloid plants, Atropa belladonna (80% identity) and Hyoscyamus niger (79% identity). They are less similar to SPDS of S. tuberosum (66% identity). Expression of pmt1 and spds cDNA in Escherichia coli yielded active enzymes, while pmt2 expression resulted in insoluble protein. Chimera proteins obtained by fusion of fragments of S. tuberosum pmt2 and H. niger pmt were active as PMT, if the initial part of pmt2 was used, indicating that a mutation in the terminal part of the gene caused insolubility of the enzyme. PMT1 was purified after expression in E. coli and proved to be an active N-methyltransferase without SPDS activity. The enzyme was specific for putrescine (K (M) 250 microM) and inhibited by n-butylamine and cadaverine. While spds was transcribed in all plant organs, pmt transcripts were found in small tuber sprouts only. The results confirm that in potato genes and enzymes specific for the tropane alkaloid metabolism are expressed and active.

Amino Acid Sequence↗

PubMed2006

Tailoring tropane alkaloid accumulation in transgenic hairy roots of Atropa baetica by over-expressing the gene encoding hyoscyamine 6beta-hydroxylase.

Atropa baetica hairy roots, over-expressing cDNA from Hyoscyamus niger encoding the gene for hyoscyamine 6beta-hydroxylase (H6H), were produced by Agrobacterium rhizogenes infection. The transgenic roots over-expressing h6h had an altered alkaloid profile in which hyoscyamine was entirely converted into scopolamine. In the best h6h clone, scopolamine accumulation increased 9-fold compared to plants, amounting to 5.6 mg g dry wt(-1), some of which was released into the liquid medium. Only negligible amounts of hyoscyamine were detected. In contrast, the gus control culture contained a much higher amount of hyoscyamine than scopolamine, mimicking the situation in the plant. At the molecular level, a higher conversion of hyoscyamine into scopolamine was related to a higher level of h6h mRNA; in some instances this was 5 - 10-fold higher.

Alkaloids↗

PubMed1984

A batch assay using Calcofluor fluorescence to characterize cell wall regeneration in plant protoplasts.

A batch assay to study and measure the regeneration of cell walls during the early days of culture of primary protoplasts is presented. The assay involves the measurement of Calcofluor White fluorescence on a scanning fluorometer when the Calcofluor is adsorbed to the cellulosic component of the newly synthesized cell walls. The Calcofluor fluorescence, when standardized with microcrystalline cellulose, provided a measure of cell wall cellulose. The assay was used to study cell wall regeneration in Hyoscyamus muticus L. protoplasts during 8 days of culture.

Benzenesulfonates↗

PubMedDate not supplied

Mystery root ingestion.

Patients frequently come to the emergency department or contact a poison center following exposure to plants. These cases are often challenging owing to difficulty in correct identification of the involved plant. A case of two patients who demonstrated anticholinergic syndromes after ingesting an unknown, wild plant is described. Chemical analysis of two suspect plants collected in the same location allowed a probable diagnosis of poisoning from ingestion of henbane (Hyoscyamus niger).

Atropine↗

PubMed1999

Gene for a protein capable of enhancing lateral root formation.

Analysis of genes preferentially expressed in hairy roots caused by infection with Agrobacterium rhizogenes has provided insights into the regulation of lateral root formation. A hairy root preferential cDNA, HR7, has been cloned from hairy roots of Hyoscyamus niger. HR7 encodes a novel protein partially homologous to a metallocarboxypeptidase inhibitor and is expressed exclusively in the primordium and base of lateral roots in hairy roots. Overexpression of HR7 in transgenic roots of H. niger dramatically enhances the frequency of lateral root formation. The results of this study indicate that expression of HR7 plays a critical role in initiating lateral root formation.

Amino Acid Sequence↗

PubMed2000

Association of L-DOPA with recovery following Ayurveda medication in Parkinson's disease.

Ayurveda, the Indian system of traditional medicine, uses a concoction of several spices, herbs and minerals for the treatment of diseases. In a clinical prospective study we have evaluated the efficacy of Ayurveda treatment (a concoction in cow's milk of powdered Mucuna pruriens and Hyoscyamus reticulatus seeds and Withania somnifera and Sida cordifolia roots) in 18 clinically diagnosed (with a mean Hoen and Yahr value of 2.22) parkinsonian patients. As per Ayurveda principles, 13 patients underwent both cleansing (for 28 days) and palliative therapy (56 days), 5 patients underwent palliative therapy alone (84 days). Only the former group showed significant improvement in activities of daily living (ADL) and on motor examination as per UPDRS rating. Symptomatically, they exhibited better response in tremor, bradykinesia, stiffness and cramps as compared to the latter group. Excessive salivation worsened in both the groups. Analyses of powdered samples in milk, as administered in patients, revealed about 200 mg of L-DOPA per dose. The study establishes the necessity of cleansing therapy in Ayurveda medication prior to palliative therapy. It also reveals contribution of L-DOPA in the recovery as observed in Parkinson' disease following Ayurveda medication.

Female↗

PubMed2001

Calystegine distribution in some solanaceous species.

The distribution of eight calystegines (A(3), A(5), B(1), B(2), B(3), B(4), C(1) and N(1)) and their content was investigated by gas chromatography coupled to mass spectrometry (GC-MS) in Datura metel, Atropa belladonna, Hyoscyamus albus, Mandragora autumnalis, Solanum sodomaeum, Withania somnifera, Withania frutescens and Brunfelsia nitida. The most frequently encountered calystegines were A(3), B(1), B(2) and B(3), while distribution of N(1) and C(1) was more limited. In all the investigated samples, calystegines A(5) and B(4) were never detected. This report focuses for the first time on calystegines in Withania and Brunfelsia genera and in Mandragora autumnalis and Solanum sodomaeum species.

Alkaloids↗

PubMed1998

Capillary electrophoresis for the analysis of tropane alkaloids: pharmaceutical and phytochemical applications.

Three capillary electrophoresis methods, using UV detection, were developed for the simultaneous determination of several tropane alkaloids, including atropine, scopolamine and synthetic derivatives. After optimization, the validated capillary zone electrophoresis methods were applied to the determination of these compounds in various pharmaceutical forms, such as ophthalmic and injection solutions, tablets, suppositories and aerosols. Capillary electrophoresis in the micellar mode was found to be more appropriate for the analysis of hyoscyamine and scopolamine in plant material. These two compounds are generally found together with other tropane alkaloids which present similar structures and charge to mass ratio. Furthermore, the separation of positional isomers, such as hyoscyamine and littorine generally encountered in plant extracts, was also considered. The developed method was applied to the analysis of hairy root extracts of Datura candida x Datura aurea, Datura quercifolia and Hyoscyamus albus.

Alkaloids↗

PubMed1997

Pre-steady-state study of recombinant sesquiterpene cyclases.

An Escherichia coli expression system was used to generate hexahistidyl-tagged plant sesquiterpene cyclases, which were readily purified by a single affinity chromatographic step. Genes for Hyoscyamus muticus vetispiradiene synthase (HVS), a chimeric 5-epi-aristolochene synthase (CH3), and a chimeric sesquiterpene cyclase possessing multifunctional epi-aristolochene and vetispiradiene activity (CH4) were expressed in bacterial cells, which resulted in the sesquiterpene cyclases accumulating to 50% of the total protein and 35% of the soluble protein. From initial velocity experiments, the Michaelis constant for HVS was 3.5 microM, while CH3 and CH4 exhibited smaller values of 0.7 and 0.4 microM, respectively. Steady-state catalytic constants were from 0.02 to 0.04 s-1. A combination of pre-steady-state rapid quench experiments, isotope trapping experiments, and experiments to measure the burst rate constant as a function of substrate concentration revealed that turnover in all three cyclases is limited by a step after the initial chemical step involving rupture of the carbon-oxygen bond in farnesyl diphosphate (FPP). Rate constants for the limiting step were 10-70-fold smaller than for the initial chemical step. Dissociation constants for the enzyme-substrate complex (20-70 microM) were determined from the pre-steady-state experiments and were significantly larger than the observed Michaelis constants. A mechanism that involves an initial, rapid equilibration of enzyme with substrate to form an enzyme-substrate complex, followed by a slower conversion of FPP to an enzyme-bound hydrocarbon and a subsequent rate-limiting step, is proposed for the three enzymes. Interestingly, the multifunctional chimeric enzyme CH4 exhibited both a tighter binding of FPP and a faster conversion of FPP to products than either of its wild-type parents.

Alkyl and Aryl Transferases↗

PubMedDate not supplied

Growth of plant root cultures in liquid- and gas-dispersed reactor environments.

The growth of Agrobacterium transformed "hairy root" cultures of Hyoscyamus muticus was examined in various liquid- and gas-dispersed bioreactor configurations. Reactor runs were replicated to provide statistical comparisons of nutrient availability on culture performance. Accumulated tissue mass in submerged air-sparged reactors was 31% of gyratory shake-flask controls. Experiments demonstrate that poor performance of sparged reactors is not due to bubble shear damage, carbon dioxide stripping, settling, or flotation of roots. Impaired oxygen transfer due to channeling and stagnation of the liquid phase are the apparent causes of poor growth. Roots grown on a medium-perfused inclined plane grew at 48% of gyratory controls. This demonstrates the ability of cultures to partially compensate for poor liquid distribution through vascular transport of nutrients. A reactor configuration in which the medium is sprayed over the roots and permitted to drain down through the root tissue was able to provide growth rates which are statistically indistinguishable (95% T-test) from gyratory shake-flask controls. In this type of spray/trickle-bed configuration, it is shown that distribution of the roots becomes a key factor in controlling the rate of growth. Implications of these results regarding design and scale-up of bioreactors to produce fine chemicals from root cultures are discussed.

Biotechnology↗

PubMedDate not supplied

Intrinsic oxygen use kinetics of transformed plant root culture.

Root meristem oxygen uptake, root tip extension rate, and specific growth rate are assessed as a function of dissolved oxygen level for three transformed root cultures. The influence of hydrodynamic boundary layer was considered for all measurements to permit correlation of oxygen-dependent kinetics with the concentration of oxygen at the surface of the root meristem. Oxygen uptake rate is shown to be saturated at ambient conditions, and a saturation level of approximately 300 micromole O2/(cm(3) tissue.hr) was observed for all three of these morphologically diverse root types. In nearly all cases, the observation of a minimum oxygen pressure, below which respiration, extension, or root growth would not occur, could be accounted for as a boundary layer mass transfer resistance. The critical oxygen pressure below which respiration declines is below saturated ambient oxygen conditions. In contrast, critical oxygen pressures for root tip extension were much higher; extension was nearly linear for the two thicker root types (Hyoscyamus muticus, henbain; Solanum tuberosum, potato) above ambient oxygen levels. The performance of the thinnest root, Brassica juncea (Indian mustard) was consistent with reduced internal limitations for oxygen transport. Extension rates did not correlate with biomass accumulation. The fastest growing henbain culture micro = 0.44 day(-)(1)) displayed the slowest extension rate (0.16 mm/hr), and the slowest growing mustard culture (micro = 0.22 day(-)(1)) had the fastest tip extension rate (0.3 mm/hr). This apparent paradox is explained in terms of root branching patterns, where the root branching ratio is shown to be dependent upon the oxygen-limited mersitem extension rate. The implications of these observations on the performance of root culture in bioreactors is discussed.

Brassica↗

PubMed1999

Development of a low capital investment reactor system: application for plant cell suspension culture

Growth of plant cell cultures is demonstrated in an uncontrolled, simple, and inexpensive plastic-lined vessel. Sustained specific growth rates of 0.22 day-1 for Hyoscyamus muticus cell suspension cultures are achieved in a low-cost gas-sparged bioreactor configuration (6.5 L working volume, wv) which is comparable to an "optimized" 5 L wv mechanically agitated fermentor. In an effort to reduce bioreactor costs, the need for an autoclavable vessel was eliminated. Sterilization is achieved by separate autoclaving of the plastic liner and by gas-phase sterilization using ethylene oxide. The initial run sterilized with ethylene oxide displayed a long lag, apparently due to residual sterilant gas. Because ethylene oxide could eliminate costs associated with autoclave rated vessels, a quantitative basis for aeration time was developed by experimental measurements and modeling of diffusion in the polymer liner. Operational techniques to eliminate toxicity are implemented to grow 0.2 kg dry weight of plant cells in 13 days in a 40 L (28.5 L wv) air-lift bioreactor without autoclave sterilization. The biomass yields for all reactors were statistically indistinguishable from shake flask culture.

Journal Article↗

PubMed1997

Molecular cloning and characterization of desacetoxyvindoline-4-hydroxylase, a 2-oxoglutarate dependent-dioxygenase involved in the biosynthesis of vindoline in Catharanthus roseus (L.) G. Don.

A 2-oxoglutarate-dependent dioxygenase (EC 1.14.11.11) which catalyzes the 4-hydroxylation of desacetoxyvindoline was purified to homogeneity. Three oligopeptides isolated from a tryptic digest of the purified protein were microsequenced and one oligopeptide showed significant homology to hyoscyamine 6 beta-hydroxylase from Hyoscyamus niger. A 36-mer degenerate oligonucleotide based on this peptide sequence was used to screen a Catharanthus roseus cDNA library and three clones, cD4H-1 to -3, were isolated. Although none of the three clones were full-length, the open reading frame on each clone encoded a putative protein containing the sequence of all three peptides. Primer extension analysis suggested that cD4H-3, the longest cDNA clone, was missing 156 bp at the 5' end of the clone and sequencing of the genomic clone, gD4H-8, confirmed these results. Southern blot analysis suggested that d4h is present as a single-copy gene in C. roseus which is a diploid plant, and the significant differences in the sequence of the 3'-UTR between cD4H-1 and -3 suggest that they represent dimorphic alleles of the same hydroxylase. The identity of the clone was further confirmed when extracts of transformed Escherichia coli expressed D4H enzyme activity. The D4H clone encoded a putative protein of 401 amino acids with a calculated molecular mass of 45.5 kDa and the amino acid sequence showed a high degree of similarity with those of a growing family of 2-oxoglutarate-dependent dioxygenases of plant and fungal origin. The similarity was not restricted to the dioxygenase protein sequences but was also extended to the gene structure and organization since the 205 and 1720 bp introns of d4h were inserted around the same highly conserved amino acid consensus sequences as those for e8 protein, hyoscyamine-6 beta-hydroxylase and ethylene-forming enzyme. These results provide further support that a common ancestral gene is responsible for the appearance of this family of dioxygenases. Hydroxylase assays and RNA blot hybridization studies showed that enzyme activity followed closely the levels of d4h transcripts, occurring predominantly in young leaves and in much lower levels in stems and fruits. In contrast, etiolated seedlings which contained considerable levels of d4h transcripts had almost undetectable hydroxylase activity, whereas exposure of seedlings to light resulted in a rapid increase of enzyme activity without a significant further increase in d4h transcripts over those detected in dark-grown seedlings. These results suggest that the activating effect of light may occur at a point downstream of transcription which remains to be elucidated.

Amino Acid Sequence↗

PubMed1998

Intraspecific variability of the tandem repeats in Nicotiana putrescine N-methyltransferases.

The putrescine N-methyltransferase (PMT) cDNA clone previously isolated from tobacco encodes a spermidine synthase-like protein with an 11 amino acid element repeated four times in tandem at the amino terminus. Genomic Southern blot analyses indicated that this N-terminal repeat array is found in tobacco PMTs but absent in Hyoscyamus and Atropa PMTs. A truncated tobacco PMT in which this repeat array was entirely removed still retained full enzymatic activity when expressed in Escherichia coli. Three PMT genes (NsPMT1, NsPMT2, NsPMT3) isolated from Nicotiana sylvestris encode two, five, and nine tandem repeats, respectively, in the first exon, but otherwise encode highly conserved proteins. Analysis of PCR fragments amplified from the genomes of N. tabacum and its two probable progenitors shows that one of the nine repeat elements in NsPMT3 was precisely deleted in the corresponding N. tabacum gene. These results indicate that direct tandem repeats of a 33 bp sequence that encodes 11 amino acids of no obvious function were added to the ancestral Nicotiana PMT gene, and that the tandem repetition was genetically very unstable, contracting or expanding during evolution of the Nicotiana species.

Amino Acid Sequence↗

PubMed1999

An Atropa belladonna hyoscyamine 6beta-hydroxylase gene is differentially expressed in the root pericycle and anthers.

The AbH6H gene for hyoscyamine 6beta-hydroxylase (H6H), which converts hyoscyamine to scopolamine, was isolated from Atropa belladonna. This plant also possesses a related sequence, Ab psiH6H, which appears to be a non-functional pseudo-gene. AbH6H RNA was detected in cultured root, native root and anther, but not in stem, leaf, pistil, petal, and sepal tissues. In situ hybridization, immunohistochemistry and promoter::GUS transgene analysis showed that AbH6H is expressed specifically in root pericycle cells, and in tapetum and pollen mother cells. A 671 bp 5'-upstream region from AbH6H was sufficient for pericycle-specific expression in hairy roots of A. belladonna and Hyoscyamus niger, which both produce scopolamine, but cell-specific regulation was severely compromised in tobacco hairy roots, which do not produce scopolamine.

Amino Acid Sequence↗

PubMed2000

Evaluation of modulations in heart rate variability caused by a composition of herbal extracts.

The purpose of this prospective, placebo-controlled, randomized double-blind study was the examination of changes of the basic vegetative rhythms due to Cardiodoron, a composition of extracts of blossoms from Primula officinalis and Onopordon acanthium and from the herbs of Hyoscyamus niger. In its clinical use it is known as a modulating medicine in the treatment of functional disturbances of the cardiovascular system. With use of Holter monitoring, 24-h ECG recordings were obtained from 100 healthy subjects of whom 50 took the composition and 50 a placebo. Heart rate variability was evaluated from the 24-h ECGs by means of a power spectral analysis based on the Fast Fourier Transformation (FFT). Regulative influences on the rhythmic system due to the medicine were found. After four weeks of medication half of the verum group showed a tendency to an increased variability in the low and high frequency range at night (LFn: 0.04-0.15 Hz, HFn: 0.15-0.4 Hz) in contrast to the placebo group. The mean heart rate at night (HRn) showed a tendency towards a normalization in the verum group: in subjects with a low HRn the heart rate was increased and in subjects with a high HRn the heart rate was decreased. This effect could not be observed in the placebo group. After two further weeks without any medication this difference between verum and placebo was abolished.

Adult↗

PubMed2005

A DNA microarray for the authentication of toxic traditional Chinese medicinal plants.

A silicon-based DNA microarray was designed and fabricated for the identification of toxic traditional Chinese medicinal plants. Species-specific oligonucleotide probes were derived from the 5S ribosomal RNA gene of Aconitum carmichaeli, A. kusnezoffi, Alocasia macrorrhiza, Croton tiglium, Datura inoxia, D. metel, D. tatula, Dysosma pleiantha, Dy. versipellis, Euphorbia kansui, Hyoscyamus niger, Pinellia cordata, P. pedatisecta, P. ternata, Rhododendron molle, Strychnos nux-vomica, Typhonium divaricatum and T. giganteum and the leucine transfer RNA gene of Aconitum pendulum and Stellera chamaejasme. The probes were immobilized via dithiol linkage on a silicon chip. Genomic target sequences were amplified and fluorescently labeled by asymmetric polymerase chain reaction. Multiple toxic plant species were identified by parallel genotyping. Chip-based authentication of medicinal plants may be useful as inexpensive and rapid tool for quality control and safety monitoring of herbal pharmaceuticals and neutraceuticals.

Base Sequence↗

PubMed1991

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 knowledge contributes the basis upon which it has become feasible to design a strategy by which the flux in these pathways may be enhanced at the genomic level. This review presents a summary of the state-of-the-art pertaining to these pathways and discusses the strategy to be adopted for a molecular approach to their manipulation, together with some of the pitfalls that may arise when trying to alter their natural regulation.

Journal Article↗