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PubMed1994

The influence of Datura ferox alkaloids on egg-laying hens.

Seeds of the weed Datura ferox are frequent contaminants of raw materials used for animal feed. In this study a mixture of scopolamine and hyoscyamine (98:2), the 2 main alkaloids of Datura ferox seeds, was incorporated at 4 total alkaloid levels (1.5, 15, 75 or 150 mg/kg feed) into a control diet fed to 100 egg-laying hens for 3 mo. Alkaloid doses of 150 mg/kg feed reduced egg production for the first 5-6 w of feeding, whereas lower doses had no effect. Egg weight, eggshell thickness and body weight of hens were unaffected at all doses. Doses of 150 mg/kg feed produced significant increases in the cardiac rate of hens after 5 w. Breathing frequency at all doses was unaffected. Determination of plasma aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and leucine aminopeptidase activities, as well as autopsy and histological examinations, revealed no obvious alkaloid-related toxic effects. It was concluded that a total alkaloid dose as high as 75 mg/kg feed can be safely administered to egg-laying hens.

Animal Feed↗
PubMed1977

Dietary selenium status and pyrrolizidine alkaloid metabolism in vitro by rat liver microsomes.

The effect of dietary selenium status on the metabolism of pyrrolizidine alkaloids (monocrotaline, and mixed pyrrolizidine alkaloid from Senecio jacobaea) by rat liver microsomes in vitro was studied. In two experiments, there was no difference in the rate of metabolism of alkaloid by microsomes from selenium deficient or selenium supplemented rats. Selenium deficiency was confirmed by measurement of erythrocyte glutathione peroxidase. Administration of excess selenium by i.p. injection did not affect alkaloid metabolism. It was concluded that dietary selenium status was unlikely to influence the metabolism of pyrrolizidine alkaloids.

Animals↗
PubMed1997

The discovery of alkaloids.

This paper presents the history of the discovery of the first alkaloids. Isolation of alkaloids is connected with the study of the active principles of medicines of plant origin, for example opium and cinchona bark. Sertürner described morphine as a plant alkali and claimed that it was capable of neutralizing free acids yielding salts. The recognition of alkaloids as a new class of compounds was an important step at that time because of the dogmatic denial of the possible existence of plant bases. Isolation of alkaloids is a significant event from the point of view of chemistry, physiology and medicine. The discovery caused essential conceptual changes in chemistry. Priority claims with reference to the discovery of the alkaloids are also reviewed.

Alkaloids↗
PubMed1998

Teratogenic and fetotoxic effects of two piperidine alkaloid-containing lupines (L. formosus and L. arbustus) in cows.

Cleft palate and minor front limb contractures were induced in calves by maternal ingestion of the piperidine alkaloid-containing lupines, Lupinus formosus and L. arbustus. Crooked calf disease, which includes an occasional cleft palate, is a congenital condition of widespread occurrence in cattle in the western U.S. and Canada. It is known to occur after maternal ingestion of certain species of Lupinus during specific gestational periods. Although many lupine species contain quinolizidine alkaloids including the teratogenic alkaloid anagyrine, L. formosus and L. arbustus produce piperidine alkaloids including the reported teratogen ammodendrine. In addition to ammodendrine, L. formosus contains both N-acetyl hystrine and N-methyl ammodendrine, whereas L. arbustus contains ammodendrine, trace amounts of N-methyl ammodendrine, and no N-acetyl hystrine. L. formosus and L. arbustus were fed to pregnant cows at equivalent ammodendrine doses during a 10-day period from days 40-50 of gestation. One calf from a cow fed L. formosus had a full cleft palate. Embryonic death and resorption of one fetus and minor front limb contractures (arthrogryposis) in another calf occurred with two cows fed L. arbustus. Alkaloid analysis of blood samples taken during the feeding period, and up to and including 48 hours after the last dose, demonstrated comparative plasma elimination times with N-methyl ammodendrine > ammodendrine > N-acetyl hystrine. The objectives of this experiment were to: 1) determine if N-acetyl hystrine is a potential teratogen; and 2) define the narrow cleft palate induction period in cows.

Alkaloids↗
PubMedDate not supplied

Solid-phase extraction cleanup and liquid chromatography with ultraviolet detection of ephedrine alkaloids in herbal products.

A solid-phase extraction (SPE) cleanup and a liquid chromatographic (LC) method with UV detection is presented for analysis of up to 7 ephedrine alkaloids in herbal products. Alkaloids from herbal products are extracted with acidified buffer, isolated on a propylsulfonic acid SPE column, eluted with a high-ionic-strength buffer, and separated by LC with detection at 255 nm. LC separation is performed by isocratic elution on a YMC phenyl column with 0.1 M sodium acetate-acetic acid (pH = 4.8) containing triethyl-amine and 2% acetonitrile. Ephedrine alkaloids are completely separated in 15 min. Average recovery of 5 common alkaloids from 3 spiked matrixes is 90%, with an average relative standard deviation (RSD) of 4.4% for alkaloid spikes between 0.5 and 16 mg/g. Average quantitation of ephedrine and pseudoephedrine from 6 herbal products is 97% of declared label claims, and average quantitation of synephrine from an herbal dietary product is 85% of label claim (RSD, 3.2%). Recoveries of synephrine, norephedrine, ephedrine, pseudoephedrine, N-methylephedrine, and N-methylpseudoephedrine spiked in 4 herbal products averaged 95%. Results of ruggedness testing and of a second laboratory validation of the procedure are also presented.

Acetic Acid↗
PubMed2001

Effects of stress factors, bioregulators, and synthetic precursors on indole alkaloid production in compact callus clusters cultures of Catharanthus roseus.

Compact callus cluster (CCC) cultures established from Catharanthus roseus consist of cohesive callus aggregates displaying certain levels of cellular or tissue differentiation. CCC cultures synthesize about two-fold more indole alkaloids than normal dispersed-cell cultures. Our studies here show that additions of KCl, mannitol, and a variety of synthetic precursors and bioregulators to the CCC cultures markedly improved indole alkaloid production and release of these alkaloids into the medium. Treatment with 250 mM mannitol and 4 g/l KCl yielded 42.3 mg l(-1) and 33.6 mg l(-1)of ajmalicine, respectively; these amounts were about four-fold higher than the control. Succinic acid, tryptamine, and tryptophan feedings also significantly increased ajmalicine (41.5 mg l(-1), 36.9 mg l(-1), and 31.8 mg l(-1), respectively) and catharanthine (21.1 mg l(-1), 17.2 mg l(-1), and 18 mg l(-1), respectively) production by the CCC cultures, while geraniol feeding inhibited biomass and alkaloid accumulation. We also found that tetramethyl ammonium bromide could significantly improve ajmalicine production (49.3 mg l(-1)) and catharanthine production (18.3 mg l(-1)) in C. roseus CCC cultures. The mechanisms responsible for these treatment effects are discussed herein.

Acyclic Monoterpenes↗
PubMed2001

Biotransformation of alkaloids.

Biotransformations of alkaloids over the last decade have continued to encompass a wide variety of substrates and enzymes. The elucidation of novel alkaloid biosynthetic and catabolic pathways will continue to furnish new biocatalysts for the synthetic organic chemist. Furthermore, an improved understanding of the genetic and biochemical basis of metabolic pathways will also permit the engineering of pathways in plants and other heterologous hosts for the production of therapeutically important alkaloids. The combination of increasing commercial interest and advances in molecular biology will facilitate the availability of robust biocatalysts which are a prerequsite to achieve economically feasible processes for the production of alkaloid-based therapeutics.

Alkaloids↗
PubMed2001

Insect repellent activity of diterpenoid alkaloids.

Diterpenoid and norditerpenoid alkaloids were tested against Tribolium casteneum (Herbst.) in order to assess their repellent activity. Of 29 tested alkaloids, 21 compounds showed promising insect repellent activity, while eight of them were not found to be active. The alkaloids were obtained from Delphinium, Consolida and Aconitum species. The highest activity was found in hetisine, a diterpene alkaloid (59.37%) and the lowest activity in another diterpene alkaloid venulol (31.25%).

Animals↗
PubMed2006

Quantitative analyses of indoloquinazoline alkaloids in Fructus Evodiae by high-performance liquid chromatography with atmospheric pressure chemical ionization tandem mass spectrometry.

Fructus Evodiae (Wuzhuyu), the fruits of Evodia rutaecarpa and related varieties, is widely used in traditional Chinese medicine. The bioactive constituents include the indoloquinazoline alkaloids rutaecarpine, evodiamine and dehydroevodiamine. A new assay based on high-performance liquid chromatography/atmospheric pressure chemical ionization tandem mass spectrometry (HPLC/UV/APCI-MS/MS) was developed for the measurement of the indoloquinazoline alkaloids in commercial Fructus Evodiae products. Initially, the MS/MS fragmentation pathways of indoloquinazoline alkaloids were investigated to identify fragment ions that might be useful for the sensitive and selective detection of trace indoloquinazoline alkaloids during LC/MS/MS. Then, quantitative MS analysis of five indoloquinazoline alkaloids in 12 commercial Fructus Evodiae products from different geographical sources was performed. Analyte recovery was in the range of 97.5-105.3% for all with relative standard deviations (RSDs) below 6%, the intra-assay and inter-assay RSDs were less than 7%, and good linear relationships were shown with correlation coefficients for the analytes exceeding 0.999. Therefore, this LC/MS/MS assay facilitated the rapid quantitative analysis of rutaecarpine, evodiamine, evodiamide, 14-formyldihydrorutaecarpine and dehydroevodiamine in 12 commercial Fructus Evodiae products with excellent recovery, repeatability, accuracy and sensitivity. This method is simple and specific and can be used for identification and quality control of this traditional Chinese remedy.

Chromatography, High Pressure Liquid↗
PubMed2004

Elimination of ergoline alkaloids following treatment of Ipomoea asarifolia (Convolvulaceae) with fungicides.

Ergoline alkaloids are constituents of Clavicipitaceous fungi living on Poaceae plants. Ergoline alkaloids as well as volatile oil are also present in Ipomoea asarifolia Roem. & Schult (Convolvulaceae). Treatment of this plant with two fungicides (Folicur, Pronto Plus) eliminates the ergoline alkaloids but not the volatile oil. Elimination of ergoline alkaloids occurs concomitantly with loss of fungal hyphae associated with secretory glands on the upper leaf surface of the Ipomoea plant. Our observations suggest that accumulation of ergoline alkaloids in the Convolvulaceae may depend on the presence of a plant-associated fungus.

Ergolines↗
PubMed1995

Tropane alkaloids and toxicity of Convolvulus arvensis.

Horses in a few, localized northern Colorado pastures exhibited weight loss and colic. At post mortem, intestinal fibrosis and vascular sclerosis of the small intestine was identified. The pastures where the affected horses grazed were overrun by field bindweed (Convolvulus arvensis). Bindweed from the pasture was found to contain the tropane alkaloids tropine, pseudotropine, and tropinone and the pyrrolidine alkaloids cuscohygrine and hygrine. Laboratory mice readily ate C. arvensis and exhibited a variety of abnormal clinical signs depending on the amount eaten. Similar alkaloids have been found in other Convolvulus species and cuscohygrine and calystegines (polyhydroxytropanes) have been previously reported from C. arvensis roots. This is the first report of simple tropane alkaloids in C. arvensis, a world wide problem weed. Pseudotropine, the major alkaloid, is known to affect motility and might represent a causative agent for the observed cases of equine intestinal fibrosis.

Animals↗
PubMed2001

Fate of an alkaloidal nuptial gift in the moth Utetheisa ornatrix: systemic allocation for defense of self by the receiving female.

In the moth Utetheisa ornatrix defensive pyrrolizidine alkaloids are sequestered by both sexes as larvae from their foodplants. The adult male transmits some of this alkaloid to the female at mating for eventual incorporation into the eggs. We now show by chemical analyses that the female herself is the first beneficiary of the alkaloid she receives from the male. By the end of mating the male's alkaloid is found already to be generally distributed throughout the female's body (including even the wings), while it is still largely absent from the ovaries. This result is in line with our earlier finding that the male's alkaloidal gift can itself suffice to render a female fully protected against spiders from the moment she uncouples from the male.

Journal Article↗
PubMed2002

Genotoxic and recombinogenic activities of the two beta-carboline alkaloids harman and harmine in Saccharomyces cerevisiae.

The cytotoxical beta-carboline alkaloids harman and harmine occur in medical plants and in a variety of foods, alcoholic beverages, and industrial waste. We applied them to the yeast Saccharomyces cerevisiae to test for putative genotoxicity, mutagenicity and recombinogenicity and to determine whether harman and harmine produced repairable DNA damage. Harmine was more cytotoxic than harman for exponentially growing haploid and diploid cells. Only harmine-induced crossing-over and mitotic gene conversion but both alkaloids were frameshift mutagens in yeast. Mutants defective in excision-resynthesis repair (rad3 and rad1), in error-prone repair (rad6) and in recombinational repair (rad52) showed enhanced sensitivity to harmine and harman, but the ranking of sensitivities was different for the two alkaloids. It appears that both alkaloids are probably capable of inducing DNA single and/or double strand breaks. An epistatic interaction was shown between rad3-e5 and rad52-1 mutants alleles, indicating that excision-resynthesis and strand-break repair may have common steps in the repair of DNA damage induced by these alkaloids. The non-epistatic interaction observed in rad1Delta rad6Delta double mutants indicated that both excision-resynthesis and error-prone repair are independently involved in repair of harman- and harmine-induced DNA lesions.

Carbolines↗
PubMed1997

Palladium(0)-Catalyzed Heteroarylation of 2- and 3-Indolylzinc Derivatives. An Efficient General Method for the Preparation of (2-Pyridyl)indoles and Their Application to Indole Alkaloid Synthesis.

Palladium(0)-catalyzed coupling of (1-(benzenesulfonyl)-2-indolyl)zinc chloride (1) and (1-(tert-butyldimethylsilyl)-3-indolyl)zinc chloride (6) with diversely substituted (alkyl, methoxy, methoxycarbonyl, nitro, hydroxy) 2-halopyridines gives the corresponding 2- and 3-(2-pyridyl)indoles [4 and 7 (or 8), respectively] in excellent yields. A series of other 3-(heteroaryl)indoles (pyrazinyl, furyl, thienyl, indolyl) have been similarly prepared from 6. The potential of some of these (2-pyridyl)indoles in alkaloid synthesis is demonstrated. Thus, from 2-(2-pyridyl)indole 4b, a new synthetic entry to the indolo[2,3-a]quinolizidine system, involving stereoselective hydrogenation of the pyridine ring with subsequent electrophilic cyclization upon the indole 3-position from an appropriately N(b)-substituted 2-(2-piperidyl)indole, is reported. For this purpose, Pummerer cyclizations have been extensively studied. Whereas the indole-unprotected sulfoxide 17 gives the corresponding indoloquinolizidine 19 in low yield and mainly undergoes an abnormal Pummerer cyclization that ultimately leads to sulfide 18, the N(a)-protected sulfoxides 24a and 24b afford the respective indoloquinolizidines 25a,b in 70% yield. On the other hand, the conversion of 3-(2-pyridyl)indole 8k into tetracyclic ketone 35 by stereoselective hydrogenation, followed by cyclization of the resulting all-cis-3-(2-piperidyl)indole 34, represents a formal synthesis of Strychnos alkaloids with the strychnan skeletal type (tubifoline, tubifolidine, 19,20-dihydroakuammicine). A similar conversion of 8j into nordasycarpidone constitutes a formal synthesis of the alkaloids of the uleine group. Reduction of nordasycarpidone leads to tetracycle 37, an advanced intermediate in a previous synthesis of tubotaiwine, a Strychnos alkaloid with the aspidospermatan skeletal type. Finally, piperidylindole 34 was transformed into tetracycle 41, an ABDE substructure of akuammiline alkaloids, by a sequence involving the skeletal rearrangement of an intermediate spiroindolenine as the crucial step.

Journal Article↗
PubMed1993

Cytotoxic and antimalarial alkaloids from the tubers of Stephania pierrei.

Biological evaluation of extracts prepared from the tubers of Stephania pierrei revealed cytotoxic and antimalarial activity. During the course of separation, two new aporphine alkaloids, (-)-asimilobine-2-O-beta-D-glucoside [2] and (-)-nordicentrine [8], in addition to twenty-one known isoquinoline alkaloids, were isolated. Each isolate was assessed for cytotoxic and antimalarial activities. It was found that the cytotoxicity of S. pierrei was mainly due to the presence of the aporphine alkaloids containing the 1,2-methylenedioxy group 3-10, whereas the antimalarial activity was attributed to the nonquaternary aporphine alkaloids 1, 3-10 and the tetrahydroprotoberberines possessing a phenolic functionality, 13-15, 18. None of the isolates showed a degree of selectivity comparable to that of antimalarial drugs such as chloroquine, quinine, mefloquine, and artemisinin. Comparison of the alkaloid content of S. pierrei and Stephania erecta strongly suggested separate identities for the two plants.

Animals↗
PubMed1997

(+)-Angchibangkine, a new type of bisbenzylisoquinoline alkaloid, and other dimers from Pachygone dasycarpa.

Analysis of the alkaloidal fraction of the stem bark extract of Pachygone dasycarpa (Menispermaceae) resulted in the isolation of 10 known bisbenzylisoquinolines, (+)-tetrandrine, (+)-penduline, (+)-fangchinoline, (+)-atherospermoline, (+)-N-methyl-7-O-demethylpeinamine, (+)-daphnoline, (4-)-isotrilobine (1), (+)-cocsuline (2), (+)-tricordatine (3), (+)-2'-norcocsuline, and the new alkaloid (+)-12-O-methyltricordatine (4). The last bisbenzylisoquinoline alkaloid isolated, (+)-angchibangkine (5), is the first member of this alkaloid class found to possess three diphenyl ether bridges in the 7-6',8-7', and 11-12' positions. Structure elucidation of these alkaloids and of (+)-O-methylangchibangkine (6) was achieved by analysis of spectral data. Compounds 4-6 show antiplasmodial activity against Plasmodium falciparum.

Animals↗
PubMed1999

Antiplasmodial activity of extracts and alkaloids of three Alstonia species from Thailand.

Methanol extracts prepared from various parts of Alstonia scholaris, A. macrophylla and A. glaucescens, collected from Thailand, have been assessed for antiplasmodial activity against multidrug-resistant K1 strain of Plasmodium falciparum cultured in human erythrocytes. Pronounced antiplasmodial activity was exhibited by methanol extract of the root bark of A. macrophylla with an IC50 value of 5.7 micrograms/ml. Thirteen indole alkaloids were isolated from the active extract. These alkaloids and a semisynthetic bisindole O-acetylmacralstonine were subsequently tested against the K1 strain of P. falciparum. Pronounced antiplasmodial activity was observed mainly among the bisindole alkaloids, particularly villalstonine and macrocarpamine with IC50 values of 0.27 and 0.36 microM, respectively. The potent alkaloids were further tested against T9-96, the chloroquine-sensitive strain of P. falciparum. It has been found that the active alkaloids, in contrast to chloroquine, have significantly higher affinity to the K1 strain than to the T9-96 strain.

Animals↗
PubMed2004

Alkaloids from Cassytha filiformis and related aporphines: antitrypanosomal activity, cytotoxicity, and interaction with DNA and topoisomerases.

Cassytha filiformis (Lauraceae), a widely distributed parasitic plant, contains several aporphine alkaloids and is often used in African folk medicine to treat cancer, African trypanosomiasis and other diseases. In a previous investigation, we showed that the alkaloid plant extract and the isolated aporphines possessed in vitro cytotoxic properties. In this paper, we evaluated the in vitro activity of the alkaloid extract (IC50 = 2.2 microg/mL) and its three major aporphine alkaloids (actinodaphnine, cassythine, and dicentrine) on Trypanosoma brucei brucei as well as four related commercially available aporphines (bulbocapnine, glaucine, isocorydine, boldine). Only the three alkaloids from Cassytha filiformis were active on the trypanosomes in vitro (IC50 = 3-15 microM). Additionally, we compared the cytotoxicity of these seven compounds on HeLa cells. Glaucine was the most cytotoxic compound on HeLa cells (IC50 = 8.2 microM) in the series. In order to elucidate their mechanism of action, the binding mode of these molecules to DNA was studied by UV absorption, circular and linear dichroism spectroscopy. The results of the optical measurements indicated that all seven aporphines effectively bind to DNA and behave as typical intercalating agents. Biochemical experiments showed that actinodaphnine, cassythine and dicentrine also interfere with the catalytic activity of topoisomerases in contrast to the four other aporphines. These interactions with DNA may explain, at least in part, the effects observed on cancer cells and on trypanosomes.

Animals↗