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PubMed2002

Inhibition of growth of microcultured Hancornia speciosa shoots by 3beta-hydroxylated gibberellins and one of their C-3 deoxy precursors.

Gibberellins (GAs) A(1), A(3), A(4) and A(7), all 3beta-hydroxylated, growth-active GAs, significantly inhibited shoot elongation and the formation of nodes in in vitro-grown Hancornia speciosa, as did GA(20), a 3-deoxy precursor of GA(1). Ancymidol, an early-stage inhibitor of GA biosynthesis, significantly retarded shoot elongation without affecting the formation of nodes. Co-application of ancymidol and GA(1 )did not overcome the ancymidol-induced growth retardation. Trinexapac-ethyl, which can inhibit 3beta-hydroxylation (GA activation) and 2beta-hydroxylation (GA inactivation), gave no significant response on either shoot elongation or node formation, while two isomers of 16,17-dihydro GA(5), also inhibitors of GA 3beta-hydroxylation, significantly inhibited both shoot growth and the formation of nodes. These unusual results may indicate a unique metabolism for GAs in microcultured shoots of H. speciosa.

Apocynaceae↗
PubMed2002

Immunolocalization of beta-D-glucans, pectins, and arabinogalactan-proteins during intrusive growth and elongation of nonarticulated laticifers in Asclepias speciosa Torr.

Nonarticulated laticifers are latex-containing cells that elongate indefinitely and grow intrusively between the walls of meristematic cells. To identify biochemical mechanisms involved in the growth of nonarticulated laticifers, we have analyzed the distribution of various polysaccharides and proteoglycans in walls of meristematic cells in contact with laticifers, nonadjacent to laticifers, and in laticifer walls. In the shoot apex of Asclepias speciosa, the levels of callose and a (1-->4)-beta-galactan epitope are lower in meristematic walls in contact with laticifers than in nonadjacent walls. In contrast, we did not detect a decline in xyloglucan, homogalacturonan, and arabinogalactan-protein epitopes upon contact of meristematic cells with laticifers. Laticifer elongation is also associated with the development of a homogalacturonan-rich middle lamella between laticifers and their neighboring cells. Furthermore, laticifers lay down walls that differ from those of their surrounding cells. This is particularly evident for epitopes in rhamnogalacturonan I. A (1-->5)-alpha-arabinan epitope in this pectin is more abundant in laticifers than meristematic cells, while the opposite is observed for a (1-->4)-beta-galactan epitope. Also, different cell wall components exhibit distinct distribution patterns within laticifer walls. The (1-->5)-alpha-arabinan epitope is distributed throughout the laticifer walls while certain homogalacturonan and arabinogalactan-protein epitopes are preferentially located in particular regions of laticifer walls. Taken together, our results indicate that laticifer penetration causes changes in the walls of meristematic cells and that there are differences in wall composition within laticifer walls and between laticifers and their surrounding cells.

Apocynaceae↗
PubMed2003

Mechanical, chemical and X-ray analysis of wood in the two tropical lianas Bauhinia guianensis and Condylocarpon guianense: variations during ontogeny.

Mechanical and chemical properties as well as microfibril angles of wood tissues from different ontogenetic stages are determined for the neotropical lianas Bauhinia guianensis and Condylocarpon guianense. The mechanical properties include the elastic moduli under bending and under dynamic torsion. The chemical analyses cover (i) the content of cellulose, lignin and hemicelluloses fractions, (ii) the monomeric composition of the uncondensed lignin, and (iii) the composition of the hemicelluloses with respect to neutral monosaccharides. By comparing the wood properties of these lianas with the corresponding properties of wood from self-supporting deciduous trees, common characteristics and differences are revealed. Additionally, the changes in the lignin and polysaccharides fractions as well as the variations in microfibril orientation that occur during ontogeny of the two liana species are discussed with regard to their implications for the mechanical properties of wood.

Apocynaceae↗
PubMed2006

Arbuscular mycorrhizal fungi increased early growth of two nontimber forest product species Dyera polyphylla and Aquilaria filaria under greenhouse conditions.

Nontimber forest products (NTFPs) represent an important source of income to millions of people in tropical forest regions, but some NTFP species have decreased in number and become endangered due to overexploitation. There is increasing concern that the planting stocks of Dyera polyphylla and Aquilaria filaria are not sufficient to sustain the yield of NTFPs and promote forest conservation. The objective of this study was to determine the effect of two arbuscular mycorrhizal (AM) fungi, Glomus clarum and Gigaspora decipiens, on the early growth of two NTFP species, D. polyphylla and A. filaria, under greenhouse conditions. The seedlings of both species were inoculated with G. clarum or G. decipiens, or uninoculated (control) under greenhouse conditions. Percentage of AM colonization, plant growth, survival rate, and nitrogen (N) and phosphorus (P) concentrations were measured after 180 days of growth. The percentage of AM colonization of D. polyphylla and A. filaria ranged from 87 to 93% and from 22 to 39%, respectively. Colonization by G. clarum and G. decipiens increased plant height, diameter, and shoot and root dry weights. Shoot N and P concentrations of the seedlings were increased by AM colonization by as much as 70-153% and 135-360%, respectively. Survival rates were higher in the AM-colonized seedlings at 180 days after transplantation than in the control seedlings. The results suggest that AM fungi can accelerate the establishment of the planting stocks of D. polyphylla and A. filaria, thereby promoting their conservation ecologically and sustaining the production of these NTFPs economically.

Apocynaceae↗
PubMed2006

Effect of Caralluma fimbriata extract on appetite, food intake and anthropometry in adult Indian men and women.

Caralluma fimbriata is an edible cactus, used by tribal Indians to suppress hunger and enhance endurance. The effect of Caralluma extract was assessed in overweight individuals by a placebo controlled randomized trial. Fifty adult men and women (25-60 years) with a body mass index (BMI) greater than 25 kg/m2 were randomly assigned into a placebo or experimental group; the latter received 1 g of Caralluma extract per day for 60 days. All subjects were given standard advice regarding a weight reducing diet and physical activity. At the end of 30 and 60 days of intervention, blood glucose and lipids, anthropometric measurements, dietary intake and assessment of appetite was performed. Waist circumference and hunger levels over the observation period showed a significant decline in the experimental group when compared to the placebo group. While there was a trend towards a greater decrease in body weight, body mass index, hip circumference, body fat and energy intake between assessment time points in the experimental group, these were not significantly different between experimental and placebo groups. Caralluma extract appears to suppress appetite, and reduce waist circumference when compared to placebo over a 2 month period.

Adult↗
PubMed2004

Purification and partial amino acid sequences of the enzyme vinorine synthase involved in a crucial step of ajmaline biosynthesis.

The acetyl-CoA-dependent enzyme vinorine synthase was isolated from hybrid cell suspension cultures of Rauvolfia serpentina and Rhazya stricta. The sarpagan-type alkaloid gardneral was used as a substrate of the enzyme leading to the ajmalan-type 10-methoxyvinorine. An HPLC-based assay was developed to monitor vinorine synthase activity, which allowed establishing a five step purification procedure combining anion exchange, hydrophobic interaction, hydroxyapatite and gel filtration. Purification resulted in a yield of 0.2% and an approximately 991-fold enrichment of the acetyltransfer activity. SDS-PAGE analysis showed a Mr for the enzyme of approximately 50 kDa. The four peptide fragments generated by proteolysis of the pure enzyme with endoproteinase LysC and the N-terminal part of the enzyme were sequenced. The enzyme preparation (> 875-fold enrichment) delivering the N-terminal sequence was isolated from R. serpentina cell suspensions. Sequence alignment of the five peptides showed highest homologies in a range of 30-71% to acetyltransferases from other higher plants involved in natural plant product biosynthesis. Based on the partial sequences vinorine synthase is probably a novel member of the BAHD enzyme super family.

Acetyl-CoA C-Acetyltransferase↗
PubMed2006

Three acetylated flavonol glycosides from Forsteronia refracta that specifically inhibit p90 RSK.

A survey of plant extracts for the presence of p90 ribosomal S6 kinase (RSK) inhibitors resulted in the isolation of three acetylated flavonol glycosides. Kaempferol 3-O-(2'',4''-O-diacetyl-alpha-l-rhamnopyranoside) (1), kaempferol 3-O-(3'',4''-O-diacetyl-alpha-l-rhamnopyranoside) (2), and kaempferol-3-O-(4''-O-acetyl-alpha-l-rhamnopyranoside) (3) were isolated from Forsteronia refracta as the first RSK inhibitors. Of these, compound 2 was found to be the best inhibitor with an IC(50) value of 89 nM.

Acetylation↗
PubMed2005

Isolation, characterization and antiplasmodial activity of steroidal alkaloids from Funtumia elastica (Preuss) Stapf.

Bioassay-guided fractionation of the EtOH extract of the stem bark of Funtumia elastica resulted in the isolation of four steroidal alkaloids, holarrhetine (1), conessine (2), holarrhesine (3) and isoconessimine (4). Their structures were determined on the basis of 1D- and 2D-NMR techniques and mass spectrometry. Compounds 1-4 exhibited in vitro antiplasmodial activity against the chloroquine-resistant strain FcB1 of Plasmodium falciparum with IC50 values ranging from 0.97 to 3.39 microM. They showed weak cytotoxicity against a rat cell line L-6 with IC50 values ranging from 5.13 to 36.55 microM.

Alkaloids↗
PubMed2006

A complex homeopathic preparation for the symptomatic treatment of upper respiratory infections associated with the common cold: An observational study.

BACKGROUND: The use of complementary medicines is large and growing in both the United States and Europe. OBJECTIVE: To compare the effects of a complex homeopathic preparation (Engystol; Heel GmbH, Baden-Baden, Germany) with those of conventional therapies with antihistamines, antitussives, and nonsteroidal antiinflammatory drugs on upper respiratory symptoms of the common cold in a setting closely related to everyday clinical practice. DESIGN: Nonrandomized, observational study over a treatment period of maximally two weeks. SETTING: Eighty-five general and homeopathic practices in Germany. PARTICIPANTS: Three hundred ninety-seven patients with upper respiratory symptoms of the common cold. INTERVENTIONS: Engystol-based therapy or common over-the-counter treatments for the common cold. Patients receiving this homeopathic treatment were allowed other short-term medications, but long-term use of analgesics, antibiotics, and antiinflammatory agents was not permitted. Patients were allowed nonpharmacological therapies such as vitamins, thermotherapies, and others. MAIN OUTCOME MEASURES: The effects of treatment were evaluated on the variables fatigue, sensation of illness, chill/tremor, aching joints, overall severity of illness, sum of all clinical variables, temperature, and time to symptomatic improvement. RESULTS: Both treatment regimens provided significant symptomatic relief, and this homeopathic treatment was noninferior in a noninferiority analysis. Significantly more patients (P < .05) using Engystol-based therapy reported improvement within 3 days (77.1% vs 61.7% for the control group). No adverse events were reported in any of the treatment groups. CONCLUSION: This homeopathic treatment may be a useful component of an integrated symptomatic therapy for the common cold in patients and practitioners choosing an integrative approach to medical care.

Adult↗
PubMed2004

Eudesmane sesquiterpene glycosides from Parepigynum funingense.

A new eudesmane sesquiterpene glycoside, pterodontriol D-6-O-beta-D-glucopyranoside (1), together with a known compound, ainsliaside E (2), was isolated from the roots of Parepigynum funingense. The structure of 1 was determined by 1D and 2D-NMR spectroscopy. Compound 2 was isolated from this plant for the first time.

Apocynaceae↗
PubMed2004

Proteolytic properties of Funastrum clausum latex.

As part of a screening of latex endopeptidases from plants growing in Argentina, the presence of proteolytic activity in the latex of Funastrum clausum stems is reported. The proteases present in the crude extract showed the main characteristics of the cysteine proteolytic class, i.e. optimum pH at alkaline range, isoelectric point (pI) higher than 9.0, and inhibition of proteolytic activity by thiol blocking reagents. A remarkable thermal stability was also evident in the crude extract. Endosterolytic preference tried on p-nitrophenyl esters of N-alpha-carbobenzoxy-L-amino acids was higher for the alanine, asparagine and tyrosine derivatives. Preliminary peptidase purification by two-step ionic exchange showed the presence of two proteolytic fractions with molecular masses of approximately 24.0 kDa according to SDS-PAGE.

Apocynaceae↗
PubMed2005

Study on the antimicrobial activity of Hymatanthus sucuba.

The antimicrobial activity of Hyamatantus sucuba roots methanol extract, fractions prepared from this extract (n-hexane, CHCl(3), EtOAc, and n-butanol) and some isolated compounds were evaluated against some Gram(+) and Gram(-) bacteria and yeasts.

Alkaloids↗
PubMed2006

Antioxidant and 15-lipoxygenase inhibitory activity of rotenoids, isoflavones and phenolic glycosides from Sarcolobus globosus.

From Sarcolobus globosus, two rotenoids (villosinol and 6-oxo-6a,12a-dehydrodeguelin), one isoflavone (genistin) and four phenolic glycosides (vanillic acid 4-O-beta-d-glucoside, glucosyringic acid, tachioside and isotachioside) were identified for the first time from this species. Extracts and compounds from S. globosus were evaluated for their DPPH radical scavenging and 15-lipoxygenase (15-LO) inhibitory activities. All tested rotenoids were found to inhibit 15-LO, while they lacked DPPH radical scavenging effect.

Antioxidants↗
PubMed2004

Lack of pro-convulsant activity of the antipsychotic alkaloid alstonine.

Psychiatry co-morbidity with epilepsy is common and often requires the combined use of psychotropic and antiepileptic drugs (AEDs). For schizophrenic patients, the occurrence of seizures with atypical agents is highest among antipsychotics, although these agents are more effective in alleviating symptoms (including negative symptoms) and are associated with fewer extrapiramidal effects. The indol alkaloid alstonine is the major component of plants used by traditional Nigerian psychiatrists as anti-dementia drugs. The alkaloid presents an experimental profile very similar to the atypical antipsychotic clozapine. This study aimed to compare the pro-convulsant activity of these two antipsychotic compounds. Through repetitive administration over a 30-day period in a kindling paradigm, it is shown that, unlike clozapine, alstonine does not possess pro-convulsant activity. The data adds to previous suggestions that alstonine deserves to be scrutinized as a model for the development of newer antipsychotics.

Animals↗
PubMed2005

Topical anti-inflammatory activity of Solenostemma argel leaves.

The topical anti-inflammatory activity of Solenostemma argel Hayne leaves was evaluated using the Croton oil ear test in mice. A bioassay-guided fractionation procedure led to a highly active chloroform extract: at 300 microg/cm(2), it induced 73% oedema reduction, while the reference drug indomethacin (100 microg/cm(2)) induced 56% reduction. The extract contained a new pregnene glycoside (1, solenoside A) and the known 14 beta,15 alpha-dihydroxy-Delta(4)pregnene-3,20 dione (2), kaempferol-3-O-glucoside (3) and kaempferol-3-O-rutinoside (4). Their structures were determined by ID and 2D NMR experiments as well as HRMS. Compounds 2 and 4 showed anti-inflammatory activity comparable to that of indomethacin.

Administration, Topical↗