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1

Naturally occurring cardiac glycosides.  

PubMed

Cardiac glycoside poisoning from the ingestion of plants, particularly of oleanders, occurs with reasonable frequency in tropical and subtropical areas. We have assessed a variety of plant specimens for their cardiac glycoside content by means of radioimmunoassays with antibodies that differ in their specificity for cardiac glycosides. Significant amounts of immunoreactive cardiac glycoside were found to be present in the ornamental shrubs: yellow oleander (Thevetia peruviana); oleander (Nerium oleander); wintersweet (Carissa spectabilis); bushman's poison (Carissa acokanthera); sea-mango (Cerbera manghas); and frangipani (Plumeria rubra); and in the milkweeds: redheaded cotton-bush (Asclepias curassavica); balloon cotton (Asclepias fruiticosa); king's crown (Calotropis procera); and rubber vine (Cryptostegia grandifolia). The venom gland of the cane toad (Bufo marinus) also contained large quantities of cardiac glycosides. The competitive immunoassay method permits the rapid screening of specimens that are suspected to contain cardiac glycosides. Awareness of the existence of these plant and animal toxins and their dangers allows them to be avoided and poisoning prevented. The method is also useful for the confirmation of the presence of cardiac glycosides in serum in cases of poisoning. PMID:3086679

Radford, D J; Gillies, A D; Hinds, J A; Duffy, P

1986-05-12

2

Cardiac glycosides from erysimum cheiranthoides.  

PubMed

Two new cardiac glycosides were isolated from the seeds of Erysimum cheiranthoides. Their structures were characterized as strophanthidin glycosides of 3-O-alpha-L-rhamnopyranosyl-(1-->4)-3-O-acetyl-beta-D-digitoxopyranosyl and 3-O-beta-D-glucpyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->4)-3-O-acetyl-beta-D-digitoxopyranosyl. PMID:11711105

Lei, Zhen Huan; Jin, Zhe Xion; Ma, Ying Li; Tai, Bao Shan; Kong, Qi; Yahara, Shoji; Nohara, Toshihiro

1998-11-20

3

Anticancer activity of cardiac glycosides  

PubMed Central

Retrospective clinical data indicate that cardiac glycosides (CGs), notably digoxin, prolong the survival of carcinoma patients treated with conventional chemotherapy. CGs are known to influence the immune response at multiple levels. In addition, recent results suggest that CGs trigger the immunogenic demise of cancer cells, an effect that most likely contributes to their clinical anticancer activity.

Kepp, Oliver; Menger, Laurie; Vacchelli, Erika; Adjemian, Sandy; Martins, Isabelle; Ma, Yuting; Sukkurwala, Abdul Qader; Michaud, Mickael; Galluzzi, Lorenzo; Zitvogel, Laurence; Kroemer, Guido

2012-01-01

4

Cardiac glycosides from Erysimum cheiranthoides.  

PubMed

Two new cardiac glycosides called cheiranthosides VI (2) and VII (3) were isolated together with a known one, glucoerysimoside (1) from the seeds of Erysimum cheiranthoides. Based on spectroscopic data, the structures of 2 and 3 were characterized as periplogenin 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-fucopyranoside and periplogenin 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-antiaropyranoside, respectively. PMID:10705523

Lei, Z H; Yahara, S; Nohara, T; Tai, B S; Xiong, J Z; Ma, Y L

2000-02-01

5

Cardiac glycosides from Erysimum cheiranthoides.  

PubMed

Three new cardiac glycosides named cheiranthoside VIII (1), cheiranthoside IX (2) and cheiranthoside X (3) were isolated from the seeds of Erysimum cheiranthoides. Based on spectroscopic data, the structures of 1-3 were characterized as strophanthidin 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-antiaropyranoside, cheiranthidin 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-boiviopyranoside and cheiranthidin 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-digitoxopyranoside, respectively. The aglycone moiety possessing a carboxyl group at C-10 of 2 and 3 was regarded to be determined for the first time. PMID:12045350

Lei, Zhen-Huan; Nakayama, Hitoshi; Kuniyasu, Akihiko; Tai, Bao-Shan; Nohara, Toshihiro

2002-06-01

6

A case of nondigitalis cardiac glycoside toxicity.  

PubMed

A case is presented of cardiac glycoside poisoning in a 1-year-old patient from the plant Nerium oleander (common oleander). The patient had bradycardia, vomiting, altered level of consciousness, and no history of ingestion. Antibody-based digoxin assays may cross-react with other cardiac glycosides nonquantitatively. Chromatographic techniques can be used in the specific diagnosis. PMID:9421116

Gupta, A; Joshi, P; Jortani, S A; Valdes, R; Thorkelsson, T; Verjee, Z; Shemie, S

1997-12-01

7

Oleandrin: A cardiac glycosides with potent cytotoxicity.  

PubMed

Cardiac glycosides are used in the treatment of congestive heart failure and arrhythmia. Current trend shows use of some cardiac glycosides in the treatment of proliferative diseases, which includes cancer. Nerium oleander L. is an important Chinese folk medicine having well proven cardio protective and cytotoxic effect. Oleandrin (a toxic cardiac glycoside of N. oleander L.) inhibits the activity of nuclear factor kappa-light-chain-enhancer of activated B chain (NF-?B) in various cultured cell lines (U937, CaOV3, human epithelial cells and T cells) as well as it induces programmed cell death in PC3 cell line culture. The mechanism of action includes improved cellular export of fibroblast growth factor-2, induction of apoptosis through Fas gene expression in tumor cells, formation of superoxide radicals that cause tumor cell injury through mitochondrial disruption, inhibition of interleukin-8 that mediates tumorigenesis and induction of tumor cell autophagy. The present review focuses the applicability of oleandrin in cancer treatment and concerned future perspective in the area. PMID:24347921

Kumar, Arvind; De, Tanmoy; Mishra, Amrita; Mishra, Arun K

2013-07-01

8

Evaluating the Cancer Therapeutic Potential of Cardiac Glycosides  

PubMed Central

Cardiac glycosides, also known as cardiotonic steroids, are a group of natural products that share a steroid-like structure with an unsaturated lactone ring and the ability to induce cardiotonic effects mediated by a selective inhibition of the Na+/K+-ATPase. Cardiac glycosides have been used for many years in the treatment of cardiac congestion and some types of cardiac arrhythmias. Recent data suggest that cardiac glycosides may also be useful in the treatment of cancer. These compounds typically inhibit cancer cell proliferation at nanomolar concentrations, and recent high-throughput screenings of drug libraries have therefore identified cardiac glycosides as potent inhibitors of cancer cell growth. Cardiac glycosides can also block tumor growth in rodent models, which further supports the idea that they have potential for cancer therapy. Evidence also suggests, however, that cardiac glycosides may not inhibit cancer cell proliferation selectively and the potent inhibition of tumor growth induced by cardiac glycosides in mice xenografted with human cancer cells is probably an experimental artifact caused by their ability to selectively kill human cells versus rodent cells. This paper reviews such evidence and discusses experimental approaches that could be used to reveal the cancer therapeutic potential of cardiac glycosides in preclinical studies.

Calderon-Montano, Jose Manuel; Burgos-Moron, Estefania; Orta, Manuel Luis; Maldonado-Navas, Dolores; Garcia-Dominguez, Irene; Lopez-Lazaro, Miguel

2014-01-01

9

Antiproliferative cardiac glycosides from the latex of Antiaris toxicaria.  

PubMed

Phytochemical investigation of the latex of Antiaris toxicaria resulted in the isolation of 15 new [antiarosides J-X (1-15)] and 17 known cardiac glycosides. The effects of the cardiac glycosides on apoptosis and the expression of orphan nuclear receptor Nur77 were examined in human NIH-H460 lung cancer cells. Several of the cardiac glycosides induced apoptosis in lung cancer cells, which was accompanied by induction of Nur77 protein expression. Treatment of cancer cells with the cardiac glycosides resulted in translocation of the Nur77 protein from the nucleus to the cytoplasm and subsequent targeting to mitochondria. The results show that the cardiac glycosides exert their apoptotic effect through the Nur77-dependent apoptotic pathway. PMID:24033101

Liu, Qian; Tang, Jin-Shan; Hu, Meng-Jie; Liu, Jie; Chen, Hai-Feng; Gao, Hao; Wang, Guang-Hui; Li, Shun-Lin; Hao, Xiao-Jiang; Zhang, Xiao-Kun; Yao, Xin-Sheng

2013-09-27

10

Cardiac glycosides from Yellow Oleander (Thevetia peruviana) seeds.  

PubMed

Thevetia cardiac glycosides can lead to intoxication, thus they are important indicators for forensic and pharmacologic surveys. Six thevetia cardiac glycosides, including two with unknown structures, were isolated from the seeds of the Yellow Oleander (Thevetia peruviana (Pers.) K. Shum., Apocynaceae). LC-ESI?-MS(/MS) analysis under high-resolution conditions used as a qualitative survey of the primary glycosides did not lead to fragmentation of the aglycones. Acid hydrolysis of the polar and non-volatile thevetia glycosides under severe conditions yielded the aglycones of the thevetia glycosides and made them amenable to GC-MS analysis. Comparison of mass spectral fragmentation patterns of the aglycones, as well as high-resolution mass spectrometric and NMR data of four of the primary thevetia glycosides including the two unknowns, revealed the structures of the complete set of six thevetia glycosides. The identified compounds are termed thevetin C and acetylthevetin C and differ by an 18,20-oxido-20,22-dihydro functionality from thevetin B and acetylthevetin B, respectively. The absence of an unsaturated lactone ring renders the glycosides cardio-inactive. The procedures developed in this study and the sets of analytical data obtained will be useful for screening and structure assessment of other, particularly polar, cardiac glycosides. PMID:22196940

Kohls, Sarah; Scholz-Böttcher, Barbara M; Teske, Jörg; Zark, Patrick; Rullkötter, Jürgen

2012-03-01

11

Cardiac glycosides: Prerequisites for the development of new cardiotonic compounds  

Microsoft Academic Search

Summary Two prerequisites in a successful search for cardiac glycosides are the separability of the inotropicallyactive from the toxically-active component and knowledge of their structure-activity relationships and\\/or indispensible structural features. A number of papers show that toxic effects of heart glycosides are dependent upon inhibition of the Na+, K+-transport ATPase. This is not, however, the case with the inotropic effect,

Th. W. Güntert; H. H. A. Linde

1977-01-01

12

The direct action of cardiac glycosides on the kidneys  

Microsoft Academic Search

Cardiac glycosides exhibit a diuretic as well as a cardiotonic activity. The former is considered to be derived from the eardiotonic effect which brings about an improvement in hemodynamics and resutts in an increase in glomerula filtration and diuresis [1, 6, 10]. However ~, the data given by various authors are not in agreement wi~h this idea. Thus, in heart-

B. A. Pakhmurny; V. V. Parin

1965-01-01

13

Ex Vivo Activity of Cardiac Glycosides in Acute Leukaemia  

Microsoft Academic Search

BackgroundDespite years of interest in the anti-cancerous effects of cardiac glycosides (CGs), and numerous studies in vitro and in animals, it has not yet been possible to utilize this potential clinically. Reports have demonstrated promising in vitro effects on different targets as well as a possible therapeutic index\\/selectivity in vitro and in experimental animals. Recently, however, general inhibition of protein

Helene Hallböök; Jenny Felth; Anna Eriksson; Mårten Fryknäs; Lars Bohlin; Rolf Larsson; Joachim Gullbo; Irina Agoulnik

2011-01-01

14

Cytotoxic cardiac glycosides from the roots of Streptocaulon juventas.  

PubMed

Chemical investigation on the 75% ethanol extract of the roots of Streptocaulon juventas afforded two new cardiac glycosides, digitoxigenin 3-O-[O-?-D-glucopyranosyl-(1 ? 4)-2-O-acetyl-?-D-digitalopyranoside] (1) and periplogenin 3-O-[O-?-D-glucopyranosyl-(1 ? 4)-O-?-D-glucopyranosyl-(1 ? 4)-?-D-cymaropyranoside] (2), and thirteen known cardenolides. Structures were elucidated by spectral methods. This is the first report of the isolation of compounds 3, 10, 14, and 15 from plants of the Streptocaulon genus, while 4, 11, and 12 are hitherto unreported from Streptocaulon juventas. All the compounds were in vitro evaluated for their cytotoxic activities against the A549 cell line, and seven effective cardiac glycosides were screened against the PC-9 cell line by WST assay, which also showed strong antiproliferation activities. Moreover, the characteristic morphological changes in PC-9 cells treated with cardenolides indicated cell inhibition due to apoptosis. These results revealed that these compounds possessed potential antitumor activities. PMID:23225367

Xue, Rui; Han, Na; Sakurai, Hiroaki; Saiki, Ikuo; Ye, Chun; Yin, Jun

2013-01-01

15

Cytotoxic cardiac glycosides and coumarins from Antiaris toxicaria.  

PubMed

Eight new cardiac glycosides/aglycones (antiaritoxiosides A-G, 1-7, and antiarotoxinin B, 8), two new coumarins (anticarins A-B, 41-42), and two new flavanones (antiarones L-K, 43-44) were isolated from trunk bark of Antiaris toxicaria together with 53 known compounds. The new structures were established by extensive analysis of spectroscopic data. Compound 1 (10-carboxy and 3?-hydroxy) and compounds 3-6 (10-hydroxy) contain unique substituents that are rarely found in cardiac glycosides. The cytotoxic effects of isolated compounds against ten human cancer cell lines, KB, KB-VIN, A549, MCF-7, U-87-MG, PC-3, 1A9, CAKI-1, HCT-9 and S-KMEL-2, were tested using the sulforhodamine B assay. Five compounds (12, 16, 20, 22, and 31) showed significant cytotoxicity against all ten cancer cell lines, with notable potency at the ng/mL level against some cell lines, which merits further development as clinical trial candidates. PMID:24582402

Shi, Li-Shian; Kuo, Sheng-Chu; Sun, Han-Dong; Morris-Natschke, Susan L; Lee, Kuo-Hsiung; Wu, Tian-Shung

2014-03-15

16

Suspected cardiac glycoside intoxication in sheep and goats in Namibia due to Ornithogalum nanodes (Leighton).  

PubMed

The main clinical and necropsy features of field and experimental cases of suspected cardiac glycoside intoxication following ingestion and dosing of the plant Ornithogalum nanodes, are described. The distribution of intoxication in the area as well as a description of the plant are given. Plant samples tested for cardiac glycosides by fluorescence polarization immuno-assay (FPIA) gave a strong positive reaction. This is a new finding, as other toxic Ornithogalum species in southern Africa are devoid of cardiac glycoside activity and poisoning with them result only in a severe, often fatal diarrhoea, without obvious cardiac involvement. It is also the first record of toxicity of this particular plant. PMID:9629587

Bamhare, C

1998-03-01

17

Morphological basis of cardiac glycoside sequestration by Oncopeltus fasciatus (Dallas) (Hemiptera: Lygaeidae)  

Microsoft Academic Search

The integument of Oncopeltus fasciatus is made up of a vacuolated and a pigmented epidermal cell layer. This double layered integument is present from late embryo to adult in male and female animals reared on milkweed or sunflower seeds. Experiments with a labelled glycoside as well as retrograde ink injections suggest that O. fasciatus concentrates cardiac glycosides, normally derived from

G. G. E. Scudder; J. Meredith

1982-01-01

18

Endogenous and exogenous cardiac glycosides and their mechanisms of action.  

PubMed

Cardiac glycosides have been used for decades to treat congestive heart failure. The recent identification of cardiotonic steroids such as ouabain, digoxin, marinobufagenin, and telocinobufagin in blood plasma, adrenal glands, and hypothalamus of mammals led to exciting new perspectives in the pathology of heart failure and arterial hypertension. Biosynthesis of ouabain and digoxin occurs in adrenal glands and is under the control of angiotensin II, endothelin, and epinephrine released from cells of the midbrain upon stimulation of brain areas sensing cerebrospinal Na(+) concentration and, apparently, the body's K(+) content. Rapid changes of endogenous ouabain upon physical exercise may favor the economy of the heart by a rise of intracellular Ca(2)(+) levels in cardiac and atrial muscle cells. According to the sodium pump lag hypothesis, this may be accomplished by partial inhibition of the sodium pump and Ca(2+) influx via the Na(+)/Ca(2+) exchanger working in reverse mode or via activation of the Na(+)/K(+)-ATPase signalosome complex, generating intracellular calcium oscillations, reactive oxygen species, and gene activation via nuclear factor-kappaB or extracellular signal-regulated kinases 1 and 2. Elevated concentrations of endogenous ouabain and marinobufagenin in the subnanomolar concentration range were found to stimulate proliferation and differentiation of cardiac and smooth muscle cells. They may have a primary role in the development of cardiac dysfunction and failure because (i) offspring of hypertensive patients evidently inherit elevated plasma concentrations of endogenous ouabain; (ii) such elevated concentrations correlate positively with cardiac dysfunction, hypertrophy, and arterial hypertension; (iii) about 40% of Europeans with uncomplicated essential hypertension show increased concentrations of endogenous ouabain associated with reduced heart rate and cardiac hypertrophy; (iv) in patients with advanced arterial hypertension, circulating levels of endogenous ouabain correlate with BP and total peripheral resistance; (v) among patients with idiopathic dilated cardiomyopathy, high circulating levels of endogenous ouabain and marinobufagenin identify those individuals who are predisposed to progressing more rapidly to heart failure, suggesting that endogenous ouabain (and marinobufagenin) may contribute to toxicity upon digoxin therapy. In contrast to endogenous ouabain, endogenous marinobufagenin may act as a natriuretic substance as well. It shows a higher affinity for the ouabain-insensitive alpha(1) isoform of Na(+)/K(+)-ATPase of rat kidney tubular cells and its levels are increased in volume expansion and pre-eclampsia. Digoxin, which is synthesized in adrenal glands, seems to counteract the hypertensinogenic action of ouabain in rats, as do antibodies against ouabain, for example, (Digibind) and rostafuroxin (PST 2238), a selective ouabain antagonist. It lowers BP in ouabain- and adducin-dependent hypertension in rats and is a promising new class of antihypertensive medication in humans. PMID:17610345

Schoner, Wilhelm; Scheiner-Bobis, Georgios

2007-01-01

19

Relationship between the chemical structure and pharmacological action of cardiac glycosides of the strophanthidin series  

Microsoft Academic Search

The possibility has been shown of finding and creating highly effective cardiotonic drugs for pediatric practice on the basis of cardenolides obtained by the chemical transformation of natural cardiac glycosides.

S. S. Azizova; Z. A. Khushbaktova; Z. Paluanova; N. Sh. Pal'yants

1995-01-01

20

Na+,K(+)-ATPase inhibiting activity of cardiac glycosides from Erysimum cheiranthoides.  

PubMed

We previously reported the isolation of eleven new cardiac glycosides called cheiranthosides I-XI together with two known ones (olitoriside and erysimoside) from the seeds of Erysimum cheiranthoides L. The glycosides were evaluated for their inhibitory activity against Na+,K(+)-ATPase by comparing with typical cardiac glycosides. Two of them, cheiranthoside III and VIII, showed high inhibiting activity which was equivalent to that of digitoxin. Cheiranthoside XI containing a rhamnopyranosyl digitoxopyranosyl moiety and a carboxyl group showed the lowest activity which was similar to that of the inactive aglycone, strophanthidin. Some characteristics in the structure-activity relationship are also discussed. PMID:11458460

Lei, Z H; Kuniyasu, A; Tai, B S; Nakayama, H; Nohara, T

2001-06-01

21

Detection of poisoning by plant-origin cardiac glycoside with the Abbott TDx analyzer.  

PubMed

Cardiac glycoside poisoning caused by ingestion of plant material is common in tropical and sub-tropical areas. In evaluating the use of the Abbott TDx Digoxin II assay to detect such cases of poisoning, we found it a rapid and convenient method for confirming the ingestion of glycosides from the plants Nerium oleander, Thevetia peruviana, and Adonis microcarpa, and from the toad Bufo marinus. Here we report some clinical cases illustrating our experience with the use of this assay, and describe results of cross-reactivity studies with compounds structurally similar to digoxin. Because of the competitive nature of the immunoassay as well as the complexity of the mixture of cross-reacting cardiac glycosides present in the plant material, the measured apparent digoxin concentration is not linearly related to the cardiac glycoside concentration. PMID:2914377

Cheung, K; Hinds, J A; Duffy, P

1989-02-01

22

Method validation of a survey of thevetia cardiac glycosides in serum samples.  

PubMed

A sensitive and specific liquid chromatography tandem mass spectrometry (HPLC-ESI(+)-MS/MS) procedure was developed and validated for the identification and quantification of thevetin B and further cardiac glycosides in human serum. The seeds of Yellow Oleander (Thevetia peruviana) contain cardiac glycosides that can cause serious intoxication. A mixture of six thevetia glycosides was extracted from these seeds and characterized. Thevetin B, isolated and efficiently purified from that mixture, is the main component and can be used as evidence. Solid phase extraction (SPE) proved to be an effective sample preparation method. Digoxin-d3 was used as the internal standard. Although ion suppression occurs, the limit of detection (LOD) is 0.27 ng/ml serum for thevetin B. Recovery is higher than 94%, and accuracy and precision were proficient. Method refinement was carried out with regard to developing a general screening method for cardiac glycosides. The assay is linear over the range of 0.5-8 ng/ml serum. Finally, the method was applied to a case of thevetia seed ingestion. PMID:21376490

Kohls, Sarah; Scholz-Böttcher, Barbara; Rullkötter, Jürgen; Teske, Jörg

2012-02-10

23

Molluscicidal activity of cardiac glycosides from Nerium indicum against Pomacea canaliculata and its implications for the mechanisms of toxicity  

Microsoft Academic Search

Cardiac glycosides from fresh leaves of Nerium indicum were evaluated for its molluscicidal activity against Pomacea canaliculata (golden apple snail: GAS) under laboratory conditions. The results showed that LC50 value of cardiac glycosides against GAS was time dependent and the LC50 value at 96h was as low as 3.71mg\\/L, which was comparable with that of metaldehyde at 72h (3.88mg\\/L). These

Lingpeng Dai; Wanxian Wang; Xinjiao Dong; Renyong Hu; Xuyang Nan

2011-01-01

24

Cardiac glycoside-like structure and function of 5 beta,14 beta-pregnanes  

SciTech Connect

5 beta-Reduction and 14 beta-substitution convert the planar progesterone molecule to the cardiac glycoside configuration--A and D rings of the steroid moiety are bent toward the alpha-face relative to the B and C rings. Potency of the 5 beta,14 beta-derivative in a ({sup 3}H)ouabain binding assay or its ability to inhibit the sodium pump in red blood cells is enhanced by 3 beta-hydroxylation, 20 beta-hydroxylation, and 3 beta-glycosidation. Synthesis of 14,20 beta-dihydroxy-3 beta-(beta-D-glucopyranosyloxy)- 5 beta,14 beta-pregnane from digitoxin is described. The glucoside is 1/20 as potent as ouabain and elicits prominent, sustained, positive inotropy in isolated cardiac muscle.

Templeton, J.F.; Kumar, V.P.; Bose, D.; LaBella, F.S.

1989-08-01

25

Membrane receptor calorimetry: cardiac glycoside interaction with Na,K-ATPase  

Microsoft Academic Search

The receptor–ligand interaction between the cardiac glycoside Ouabain and purified, membrane-bound as well as micellar Na,K-ATPase is investigated. Calorimetric titrations are carried out with micromolar concentrations of the phosphorylated protein in the presence of Mg2+. The measured heat changes provide evidence for an exothermic, high affinity and specific receptor binding process as well as for a low affinity, nonspecific binding

E. Grell; E. Schick; E. Lewitzki

2001-01-01

26

Suppression of positive inotropic and toxic effects of cardiac glycosides by amiloride.  

PubMed

Effects of amiloride on the inotropic and toxic actions of cardiac glycosides were examined using left atrial muscle isolated from guinea pig heart. Preincubation of atrial muscle with amiloride significantly decreased the maximum positive inotropic effect of dihydrodigoxin but failed to reduce that of isoproterenol. Amiloride prevented the contracture and significantly reduced the incidence of arrhythmias induced by 2 microM digoxin. Similar experiments examining 5 microM digoxin-induced arrhythmias showed that amiloride increased both the time required to produce arrhythmias and the fractional occupancy of sarcolemmal Na,K-ATPase by digoxin at the onset of arrhythmias. The antagonism of cardiac glycoside actions was best observed during the decline in developed tension elicited by amiloride subsequent to its initial positive inotropic effect. Amiloride had no effect on binding site concentration for ATP-dependent [3H]ouabain binding but decreased affinity of the binding sites for ouabain in membrane preparations obtained from guinea pig heart. Furthermore, amiloride inhibited Na,K-ATPase activity and increased the IC50 value for ouabain inhibition of the enzyme. These results indicate that amiloride antagonizes the positive inotropic and toxic effects of cardiac glycosides. Possible mechanisms for the antagonism include inhibition of sarcolemmal Na+/Ca2+ or Na+/H+ exchange. PMID:2998821

Kennedy, R H; Akera, T; Brody, T M

1985-09-24

27

Zebrafish chemical screening reveals the impairment of dopaminergic neuronal survival by cardiac glycosides.  

PubMed

Parkinson's disease is a neurodegenerative disorder characterized by the prominent degeneration of dopaminergic (DA) neurons among other cell types. Here we report a first chemical screen of over 5,000 compounds in zebrafish, aimed at identifying small molecule modulators of DA neuron development or survival. We find that Neriifolin, a member of the cardiac glycoside family of compounds, impairs survival but not differentiation of both zebrafish and mammalian DA neurons. Cardiac glycosides are inhibitors of Na(+)/K(+) ATPase activity and widely used for treating heart disorders. Our data suggest that Neriifolin impairs DA neuronal survival by targeting the neuronal enriched Na(+)/K(+) ATPase ?3 subunit (ATP1A3). Modulation of ionic homeostasis, knockdown of p53, or treatment with antioxidants protects DA neurons from Neriifolin-induced death. These results reveal a previously unknown effect of cardiac glycosides on DA neuronal survival and suggest that it is mediated through ATP1A3 inhibition, oxidative stress, and p53. They also elucidate potential approaches for counteracting the neurotoxicity of this valuable class of medications. PMID:22563390

Sun, Yaping; Dong, Zhiqiang; Khodabakhsh, Hadie; Chatterjee, Sandip; Guo, Su

2012-01-01

28

Zebrafish Chemical Screening Reveals the Impairment of Dopaminergic Neuronal Survival by Cardiac Glycosides  

PubMed Central

Parkinson's disease is a neurodegenerative disorder characterized by the prominent degeneration of dopaminergic (DA) neurons among other cell types. Here we report a first chemical screen of over 5,000 compounds in zebrafish, aimed at identifying small molecule modulators of DA neuron development or survival. We find that Neriifolin, a member of the cardiac glycoside family of compounds, impairs survival but not differentiation of both zebrafish and mammalian DA neurons. Cardiac glycosides are inhibitors of Na+/K+ ATPase activity and widely used for treating heart disorders. Our data suggest that Neriifolin impairs DA neuronal survival by targeting the neuronal enriched Na+/K+ ATPase ?3 subunit (ATP1A3). Modulation of ionic homeostasis, knockdown of p53, or treatment with antioxidants protects DA neurons from Neriifolin-induced death. These results reveal a previously unknown effect of cardiac glycosides on DA neuronal survival and suggest that it is mediated through ATP1A3 inhibition, oxidative stress, and p53. They also elucidate potential approaches for counteracting the neurotoxicity of this valuable class of medications.

Sun, Yaping; Dong, Zhiqiang; Khodabakhsh, Hadie; Chatterjee, Sandip; Guo, Su

2012-01-01

29

Molluscicidal activity of cardiac glycosides from Nerium indicum against Pomacea canaliculata and its implications for the mechanisms of toxicity.  

PubMed

Cardiac glycosides from fresh leaves of Nerium indicum were evaluated for its molluscicidal activity against Pomacea canaliculata (golden apple snail: GAS) under laboratory conditions. The results showed that LC(50) value of cardiac glycosides against GAS was time dependent and the LC(50) value at 96 h was as low as 3.71 mg/L, which was comparable with that of metaldehyde at 72 h (3.88 mg/L). These results indicate that cardiac glycosides could be an effective molluscicide against GAS. The toxicological mechanism of cardiac glucosides on GAS was also evaluated through changes of selected biochemical parameters, including cholinesterase (ChE) and esterase (EST) activities, glycogen and protein contents in hepatopancreas tissues of GAS. Exposure to sublethal concentrations of cardiac glycosides, GAS showed lower activities of EST isozyme in the later stages of the exposure period as well as drastically decreased glycogen content, although total protein content was not affected at the end of 24 and 48 h followed by a significant depletion at the end of 72 and 96 h. The initial increase followed by a decline of ChE activity was also observed during the experiment. These results suggest that cardiac glycosides seriously impair normal physiological metabolism, resulting in fatal alterations in major biochemical constituents of hepatopancreas tissues of P. canaliculata. PMID:21843803

Dai, Lingpeng; Wang, Wanxian; Dong, Xinjiao; Hu, Renyong; Nan, Xuyang

2011-09-01

30

Isoform-specific Stimulation of Cardiac Na/K Pumps by Nanomolar Concentrations of Glycosides  

PubMed Central

It is well-known that micromolar to millimolar concentrations of cardiac glycosides inhibit Na/K pump activity, however, some early reports suggested nanomolar concentrations of these glycosides stimulate activity. These early reports were based on indirect measurements in multicellular preparations, hence, there was some uncertainty whether ion accumulation/depletion rather than pump stimulation caused the observations. Here, we utilize the whole-cell patch-clamp technique on isolated cardiac myocytes to directly measure Na/K pump current (IP) in conditions that minimize the possibility of ion accumulation/depletion causing the observed effects. In guinea pig ventricular myocytes, nanomolar concentrations of dihydro-ouabain (DHO) caused an outward current that appeared to be due to stimulation of IP because of the following: (1) it was absent in 0 mM [K+]o, as was IP; (2) it was absent in 0 mM [Na+]i, as was IP; (3) at reduced [Na+]i, the outward current was reduced in proportion to the reduction in IP; (4) it was eliminated by intracellular vanadate, as was IP. Our previous work suggested guinea pig ventricular myocytes coexpress the ?1- and ?2-isoforms of the Na/K pumps. The stimulation of IP appears to be through stimulation of the high glycoside affinity ?2-isoform and not the ?1-isoform because of the following: (1) regulatory signals that specifically increased activity of the ?2-isoform increased the amplitude of the stimulation; (2) regulatory signals that specifically altered the activity of the ?1-isoform did not affect the stimulation; (3) changes in [K+]o that affected activity of the ?1-isoform, but not the ?2-isoform, did not affect the stimulation; (4) myocytes from one group of guinea pigs expressed the ?1-isoform but not the ?2-isoform, and these myocytes did not show the stimulation. At 10 nM DHO, total IP increased by 35 ± 10% (mean ± SD, n = 18). If one accepts the hypothesis that this increase is due to stimulation of just the ?2-isoform, then activity of the ?2-isoform increased by 107 ± 30%. In the guinea pig myocytes, nanomolar ouabain as well as DHO stimulated the ?2-isoform, but both the stimulatory and inhibitory concentrations of ouabain were ?10-fold lower than those for DHO. Stimulation of IP by nanomolar DHO was observed in canine atrial and ventricular myocytes, which express the ?1- and ?3-isoforms of the Na/K pumps, suggesting the other high glycoside affinity isoform (the ?3-isoform) also was stimulated by nanomolar concentrations of DHO. Human atrial and ventricular myocytes express all three isoforms, but isoform affinity for glycosides is too similar to separate their activity. Nevertheless, nanomolar DHO caused a stimulation of IP that was very similar to that seen in other species. Thus, in all species studied, nanomolar DHO caused stimulation of IP, and where the contributions of the high glycoside affinity ?2- and ?3-isoforms could be separated from that of the ?1-isoform, it was only the high glycoside affinity isoform that was stimulated. These observations support early reports that nanomolar concentrations of glycosides stimulate Na/K pump activity, and suggest a novel mechanism of isoform-specific regulation of IP in heart by nanomolar concentrations of endogenous ouabain-like molecules.

Gao, Junyuan; Wymore, Randy S.; Wang, Yongli; Gaudette, Glenn R.; Krukenkamp, Irvin B.; Cohen, Ira S.; Mathias, Richard T.

2002-01-01

31

The duration of action of some cardiac glycosides and aglycones in the guinea-pig  

PubMed Central

A method is described for determining the duration of action of cardiac glycosides and aglycones in the guinea-pig. It is based on their property of potentiating the cardiac response to adenosine. The method is particularly suitable for those drugs with a short duration of action, whereas previous methods are more suitable for those drugs with longer durations of action. The duration of action of one-fifth of the lethal dose has been found for: digoxigenin, lanatoside C, ouabain, digitoxigenin-3-one, digitoxin, 3-acetyldigitoxigenin, digoxin, digitoxigenin, lanatoside A; these drugs are arranged in order of increasing duration of action. The possible relationship between the elimination of these drugs and their duration of action can provide an estimate of their rates of elimination.

Rand, M.; Stafford, Anne

1959-01-01

32

Assembling the puzzle of anti-cancer mechanisms triggered by cardiac glycosides.  

PubMed

Cardiac glycosides (CGs) are compounds used for the treatment of cardiac failure which also display strong anti-cancer activity inducing impairment of cell proliferation or activation of cell death whether by apoptosis or autophagy. Despite the fact that the sodium/potassium (Na(+)/K(+))-ATPase is a well-known target of CGs, its involvement in the anti-cancer effect of these compounds remains to be validated. Importantly, related intracellular sensor(s)/transducer(s) needs further characterization. We will discuss here key mechanisms activated by CGs including their ability to modulate the cell cycle and to regulate the expression of anti-apoptotic Bcl-2 family members, two so far marginally investigated events. PMID:22735572

Cerella, Claudia; Dicato, Mario; Diederich, Marc

2013-05-01

33

BDNF Mediates Neuroprotection against Oxygen-Glucose Deprivation by the Cardiac Glycoside Oleandrin  

PubMed Central

We have previously shown that the botanical drug candidate PBI-05204, a supercritical CO2 extract of Nerium oleander, provides neuroprotection in both in vitro and in vivo brain slice-based models for focal ischemia (Dunn et al., 2011). Intriguingly, plasma levels of the neurotrophin BDNF were increased in patients treated with PBI-05204 in a phase I clinical trial (Bidyasar et al., 2009). We thus tested the hypothesis that neuroprotection provided by PBI-05204 to rat brain slices damaged by oxygen-glucose deprivation (OGD) is mediated by BDNF. We found, in fact, that exogenous BDNF protein itself is sufficient to protect brain slices against OGD, whereas downstream activation of TrkB receptors for BDNF is necessary for neuroprotection provided by PBI-05204, using three independent methods. Finally, we provide evidence that oleandrin, the principal cardiac glycoside component of PBI-05204, can quantitatively account for regulation of BDNF at both the protein and transcriptional levels. Together, these findings support further investigation of cardiac glycosides in providing neuroprotection in the context of ischemic stroke.

Van Kanegan, Michael J.; He, Dong Ning; Dunn, Denise E.; Yang, Peiying; Newman, Robert A.; West, Anne E.

2014-01-01

34

BDNF mediates neuroprotection against oxygen-glucose deprivation by the cardiac glycoside oleandrin.  

PubMed

We have previously shown that the botanical drug candidate PBI-05204, a supercritical CO2 extract of Nerium oleander, provides neuroprotection in both in vitro and in vivo brain slice-based models for focal ischemia (Dunn et al., 2011). Intriguingly, plasma levels of the neurotrophin BDNF were increased in patients treated with PBI-05204 in a phase I clinical trial (Bidyasar et al., 2009). We thus tested the hypothesis that neuroprotection provided by PBI-05204 to rat brain slices damaged by oxygen-glucose deprivation (OGD) is mediated by BDNF. We found, in fact, that exogenous BDNF protein itself is sufficient to protect brain slices against OGD, whereas downstream activation of TrkB receptors for BDNF is necessary for neuroprotection provided by PBI-05204, using three independent methods. Finally, we provide evidence that oleandrin, the principal cardiac glycoside component of PBI-05204, can quantitatively account for regulation of BDNF at both the protein and transcriptional levels. Together, these findings support further investigation of cardiac glycosides in providing neuroprotection in the context of ischemic stroke. PMID:24431454

Van Kanegan, Michael J; He, Dong Ning; Dunn, Denise E; Yang, Peiying; Newman, Robert A; West, Anne E; Lo, Donald C

2014-01-15

35

Cytotoxicity of digitoxin and related cardiac glycosides in human tumor cells.  

PubMed

The saponin digitonin, the aglycone digitoxigenin and five cardiac glycosides were evaluated for cytotoxicity using primary cultures of tumor cells from patients and a human cell line panel (representing different cytotoxic drug-resistance patterns). Of these seven compounds, proscillaridin A was the most potent (IC(50): 6.4--76 nM), followed by digitoxin, and then ouabain, digoxin, lanatoside C, digitoxigenin and digitonin. Correlation analysis of the log IC(50) values for the cell lines in the panel showed that compound cytotoxicity was only slightly influenced by resistance mechanisms that involved P-glycoprotein, topoisomerase II, multidrug resistance-associated protein and glutathione-mediated drug resistance. Digitoxin and digoxin expressed selective toxicity against solid tumor cells from patients, while proscillaridin A expressed no selective toxicity against either solid or hematological tumor cells. The results revealed marked differences in cytotoxicity between the cardiac glycosides, both in potency and selectivity, and modes of action for cytotoxicity that differ from that of commonly used anticancer drugs. PMID:11395576

Johansson, S; Lindholm, P; Gullbo, J; Larsson, R; Bohlin, L; Claeson, P

2001-06-01

36

Recent progress in the biochemistry of plant steroids other than sterols (Saponins, glycoalkaloids, pregnane derivatives, cardiac glycosides, and sex hormones)  

Microsoft Academic Search

Recent studies concerning the biosynthesis, metabolism, and possible functions of steroids other than sterols in plants are\\u000a reviewed and discussed. These studies embrace the saponins, glycoalkaloids, pregnane derivatives, cardiac glycosides, as well\\u000a as their aglycones, and the sex hormones.

Erich Heftmann

1974-01-01

37

Cardiac glycosides induce resistance to tubulin-dependent anticancer drugs in androgen-independent human prostate cancer  

Microsoft Academic Search

Due to high prevalence and mortality and the lack of effective therapies, prostate cancer is one of the most crucial health problems in men. Drug resistance aggravates the situation, not only in human prostate cancer but also in other cancers. In this study, we report for the first time that cardiac glycosides (e.g. ouabain and digitoxin) induced resistance of human

Dong-Ming Huang; Jih-Hwa Guh; Yao-Ting Huang; Shih-Chieh Chueh; Hui-Po Wang; Che-Ming Teng

2002-01-01

38

Cardiac glycosides provide neuroprotection against ischemic stroke: Discovery by a brain slice-based compound screening platform  

PubMed Central

We report here the results of a chemical genetic screen using small molecules with known pharmacologies coupled with a cortical brain slice-based model for ischemic stroke. We identified a small-molecule compound not previously appreciated to have neuroprotective action in ischemic stroke, the cardiac glycoside neriifolin, and demonstrated that its properties in the brain slice assay included delayed therapeutic potential exceeding 6 h. Neriifolin is structurally related to the digitalis class of cardiac glycosides, and its putative target is the Na+/K+-ATPase. Other cardiac glycoside compounds tested also showed neuroprotective activity, although with lower apparent potencies. In subsequent whole-animal studies, we found that neriifolin provided significant neuroprotection in a neonatal model of hypoxia/ischemia and in a middle cerebral artery occlusion model of transient focal ischemia. The neuroprotective potential of Na+/K+-ATPase is of particular interest because of its known “druggability”; indeed, Food and Drug Administration-approved, small-molecule compounds such as digitoxin and digoxin have been in clinical usage for congestive heart failure and arrhythmias for several decades. Thus, an existing cardiac glycoside or closely related compound could provide an accelerated path toward clinical trial testing for ischemic stroke. Our findings underscore the important role that hypothesis-neutral, high-content, tissue-based screens can play in the identification of new candidate drugs and drug targets for the treatment of diseases for which validated therapeutic pathways are not currently available.

Wang, James K. T.; Portbury, Stuart; Thomas, Mary Beth; Barney, Shawn; Ricca, Daniel J.; Morris, Dexter L.; Warner, David S.; Lo, Donald C.

2006-01-01

39

Charge movements in intact amphibian skeletal muscle fibres in the presence of cardiac glycosides  

PubMed Central

Intramembrane charge movements were examined in intact voltage-clamped amphibian muscle fibres following treatment with cardiac glycosides in the hypertonic gluconate-containing solutions hitherto reported to emphasise the features of q? at the expense of q? charge. The application of chlormadinone acetate (CMA) at concentrations known selectively to block Na+-K+-ATPase conserved the steady-state voltage dependence of intramembrane charge, contributions from delayed (q?) charging transients, and their inactivation characteristics brought about by shifts in holding potential. The addition of either ouabain (125, 250 or 500 nm) or digoxin (5 nm) at concentrations previously reported additionally to influence excitation-contraction coupling similarly conserved the steady-state charge-voltage relationships, Q(V), in fully polarised fibres to give values of maximum charge, Qmax, transition voltage, V*, and steepness factor, k, that were consistent with a persistent q? component as reported on earlier occasions (Qmax? 25-27 nC ?F?1, V*? -45 to -50 mV, k? 7-9 mV). In both cases shifts in holding potential from -90 to -50 mV produced a partial inactivation that separated steeply and more gradually voltage-dependent charge components in agreement with previous characterisations. However, charge movements that were observed in the presence of either digoxin or ouabain were monotonic decays in which delayed (q?) transients could not be distinguished from the early charging records. These features persisted despite the further addition of chlormadinone acetate over a 10-fold concentration range (5-50 ?m) known to displace ouabain from the Na+-K+-ATPase. Ouabain (500 nm) restored the steady-state charge movement that was previously abolished by the addition of 2.0 mm tetracaine in common with previous results of using ryanodine receptor (RyR)-specific agents. Perchlorate (8.0 mm) restored the delayed ‘on’ relaxations and increased the prominence of the ‘off’ decays produced by q? charge following treatment with cardiac glycosides. This was accompanied by a negative (?10-15 mV) shift in the steady-state charge-voltage relationship but an otherwise conserved maximum charge, Qmax, and steepness factor, k, in parallel with previously reported effects of perchlorate following treatments with RyR-specific agents. The features of cardiac glycoside action thus parallel those of other agents that act on RyR-Ca2+ release channels yet influence the kinetics but spare the steady-state properties of intramembrane charge.

Huang, Christopher L-H

2001-01-01

40

Nerium oleander derived cardiac glycoside oleandrin is a novel inhibitor of HIV infectivity.  

PubMed

We evaluated the effectiveness of Anvirzel™, an aqueous extract of Nerium oleander on HIV infection of human peripheral blood mononuclear cells. Oleandrin, the principle cardiac glycoside (CG) in Anvirzel™ has been shown to exhibit anti-cancer properties but its efficacy against HIV is unknown. Treatment with Anvirzel™ significantly reduced the infectivity of virus produced from infected cells without any change in the total amount of virus produced. This is in contrast to treatment with AZT, a potent inhibitor of HIV replication that has been shown to significantly reduce virus production. Relative to untreated cultures, virus in cultures treated with oleandrin had significantly reduced expression of the envelope protein gp120, the sole determinant of virus infectivity, suggesting a novel mechanism underlying the impaired infectivity. These results support the potential utility of the Nerium oleander aqueous extract, containing the CG oleandrin as a novel candidate anti-HIV therapeutic. PMID:23127567

Singh, Shailbala; Shenoy, Sachin; Nehete, Pramod N; Yang, Peiying; Nehete, Bharti; Fontenot, Danielle; Yang, Guojun; Newman, Robert A; Sastry, K Jagannadha

2013-01-01

41

Digoxin and other cardiac glycosides inhibit HIF-1? synthesis and block tumor growth  

PubMed Central

A library of drugs that are in clinical trials or use was screened for inhibitors of hypoxia-inducible factor 1 (HIF-1). Twenty drugs inhibited HIF-1-dependent gene transcription by >88% at a concentration of 0.4 ?M. Eleven of these drugs were cardiac glycosides, including digoxin, ouabain, and proscillaridin A, which inhibited HIF-1? protein synthesis and expression of HIF-1 target genes in cancer cells. Digoxin administration increased latency and decreased growth of tumor xenografts, whereas treatment of established tumors resulted in growth arrest within one week. Enforced expression of HIF-1? by transfection was not inhibited by digoxin, and xenografts derived from these cells were resistant to the anti-tumor effects of digoxin, demonstrating that HIF-1 is a critical target of digoxin for cancer therapy.

Zhang, Huafeng; Qian, David Z.; Tan, Yee Sun; Lee, KangAe; Gao, Ping; Ren, Yunzhao R.; Rey, Sergio; Hammers, Hans; Chang, Daniel; Pili, Roberto; Dang, Chi V.; Liu, Jun O.; Semenza, Gregg L.

2008-01-01

42

Structural complexes in the squid giant axon membrane sensitive to ionic concentrations and cardiac glycosides  

PubMed Central

Giant nerve fibers of squid Sepioteuthis sepiodea were incubated for 10 min in artificial sea water (ASW) under control conditions, in the absence of various ions, and in the presence of cardiac glycosides. The nerve fibers were fixed in OsO(4) and embedded in Epon, and structural complexes along the axolemma were studied. These complexes consist of a portion of axolemma exhibiting a three-layered substructure, an undercoating of a dense material (approximately 0.1?m in length and approximately 70-170 A in thickness), and a narrowing to disappearance of the axon-Schwann cell interspace. In the controls, the incidence of complexes per 1,000?m of axon perimeter was about 137. This number decreased to 10-25 percent when magnesium was not present in the incubating media, whatever the calcium concentration (88, 44, or 0 mM). In the presence of magnesium, the number and structural features of the complexes were preserved, though the number decreased to 65 percent when high calcium was simultaneously present. The complexes were also modified and decreased to 26-32 percent by incubating the nerves in solutions having low concentrations of sodium and potassium. The adding of 10(-5) M ouabain or strophanthoside to normal ASW incubating solution decreased them to 20-40 percent. Due to their sensitivity to changes in external ionic concentrations and to the presence of cardiac glycosides, the complexes are proposed to represent the structural correlate of specialized sites for active ion transport, although other factors may be involved.

Villegas, GM; Villegas, J

1976-01-01

43

Cardiac glycosides inhibit p53 synthesis by a mechanism relieved by Src or MAPK inhibition  

PubMed Central

p53 is regulated at the multiple levels. We report here that p53 in multiple lines of human cancer cells is down-regulated by cardiac glycoside drugs, digoxin or ouabain, the potent inhibitors of Na+/K+-ATPase. These drugs reduced the basal levels of p53 protein at nanomolar concentrations in a dose-, time- and cancer cell line-dependent manner, but independent of p53 status of wild type (wt) or mutant. The drugs also reduced the levels of p53 induced by its activators as well as p53 transfected into human cancer cells, regardless of its status. Interestingly, the drugs had no effect on endogenous p53 in two immortalized human cell lines. Mechanistically, p53 reduction did not occur at the mRNA levels, but at the protein levels, as a result of reduced protein synthesis rather than enhanced degradation. The cellular sensitivity to drug-induced p53 reduction was not associated with the levels of ? subunits of Na+/K+-ATPase in different cell lines. While lowering extracellular K+ did not reduce p53 as did ouabain and digoxin, it did potentiate both digoxin and ouabain-induced p53 reduction in sensitive lines. Finally, p53 reduction appears to be triggered by activation of Src/MAPK signaling pathways upon drug binding to the Na+/K+-ATPase and can be completely blocked by the inhibitors of Src or MEK. This is the first report that cardiac glycoside drugs, by initiating the Src/MAPK signaling pathways, reduce the p53 levels via inhibition of p53 protein synthesis. The drugs may be useful in the treatment of human cancers with a gain-of-function p53 mutation.

Wang, Zhen; Zheng, Min; Li, Zhichuan; Li, Ruiguo; Jia, Lijun; Xiong, Xiufang; Southall, Noel; Wang, Shaomeng; Xia, Menghang; Austin, Christopher P.; Zheng, Wei; Xie, Zijian; Sun, Yi

2009-01-01

44

Effects of cardiac glycosides on excitation-contraction coupling in frog skeletal muscle fibres.  

PubMed Central

1. The effects of digoxin and ouabain on the calcium release flux from the sarcoplasmic reticulum (SR), isometric tension and intramembrane charge movement were studied in voltage clamped skeletal muscle fibres of the frog. 2. Both cardiac glycosides increased both calcium transients and simultaneously recorded tension at all membrane potentials, showing different effects on the peak and on the steady components of the calcium release flux. These effects were attained at an extracellular digoxin concentration of 5 nM and an estimated intracellular ouabain concentration of 1-2 nM. Digoxin and ouabain thus exerted their effects at the same concentration on calcium release in skeletal muscle as previously observed in isolated cardiac-type ryanodine receptor (RyR) calcium release channels. 3. The peak of SR calcium release increased at all voltages, with the largest potentiation at intermediate membrane potentials. This increase in calcium release flux was attained despite an unchanged SR calcium content. The attenuated release rate therefore reflected an increased number of open RyR channels rather than increased SR loading. 4. These effects could be attributed to an increase in calcium release activation and not a decrease in the rate of inactivation. Rather, the rate of inactivation was enhanced at all voltages as expected from the increased calcium concentration in the triadic junction. 5. In contrast, CMA (17 alpha-acetoxy-6-chloro-4, 6-pregnadiene-3,20-dione; 5 microM), a Na(+)-K(+)-ATPase inhibitor with no positive inotropic effects on the heart, neither influenced SR calcium release nor antagonized the effects of ouabain. 6. Both digoxin and ouabain preserved total intramembrane charge apart from a small negative shift in the mid-point voltage and increase in slope factor. 7. Both digoxin and ouabain induced calcium release from heavy SR vesicles at rates comparable to that induced by ryanodine or caffeine. 8. It is concluded that at least part of the inactivating component of SR calcium release involves distinct RyR calcium release channels that resemble the cardiac RyR isoform in its specific sensitivity to cardiac glycosides.

Sarkozi, S; Szentesi, P; Jona, I; Csernoch, L

1996-01-01

45

Cardiac glycosides induce autophagy in human non-small cell lung cancer cells through regulation of dual signaling pathways.  

PubMed

Na(+)/K(+)-ATPase targeted cancer therapy has attracted increasing interests of oncologists in lung cancer field. Although multiple anti-cancer mechanisms of cardiac glycosides as Na(+)/K(+)-ATPase inhibitors are revealed, the role of autophagy and related molecular signaling pathway for the class of compounds in human non-small cell lung cancer (NSCLC) cells has not been systematically examined. We herein investigated the anti-cancer effects of two representative cardiac glycosides, digoxin and ouabain, in A549 and H460 cell lines. Both agents caused significant growth inhibition at nanomolar level. The cardiac glycosides were found to induce moderate G(2)/M arrest but not apoptosis at IC(50) level in the NSCLC cell lines. Moreover, autophagy was markedly induced by both agents, as evidenced by the time- and dose-dependent increase of LC3-II, up-regulation of Atg5 and Beclin1, as well as by the observations through acridine orange staining, transmission electron microscopy and quantification of GFP-LC3 fluorescence. Importantly, AMP-activated protein kinase (AMPK) pathway was activated, resulting in mammalian target of rapamycin (mTOR) deactivation during autophagy induction. Moreover, extracellular-signal-regulated kinase 1/2 (ERK1/2) activation was simultaneously found to be involved in the autophagy regulation. Co-treatment with respective inhibitors or siRNAs could either block the autophagic phenotypes and signals, or significantly increase the cellular viability, indicating the drugs-induced autophagy plays tumor-suppressing role. This work provides first evidence showing that the cardiac glycosides induce autophagy in human NSCLC cells through regulation of both mTOR and ERK1/2 signaling pathways. The autophagy may at least partially account for the growth inhibitory effects of the compounds in human NSCLC cells. PMID:22750415

Wang, Yan; Qiu, Qiang; Shen, Jia-Jia; Li, Dian-Dong; Jiang, Xue-Jun; Si, Shu-Yi; Shao, Rong-Guang; Wang, Zhen

2012-11-01

46

Molecular modeling of cardiac glycoside binding by the human sequence monoclonal antibody 1B3.  

PubMed

The amino acid sequences of the heavy- and light-chain variable regions of the high-affinity human sequence antidigoxin monoclonal antibody 1B3 (mAb 1B3) were determined, and a structural model for the mAb's variable region was developed by homology modeling techniques. The structural model provided the basis for computationally docking digoxin and eight related cardiac glycosides into the putative binding site of mAb 1B3. Analysis of the consensus binding mode obtained for digoxin showed that the cardenolide moiety of digoxin is deeply embedded in a predominantly hydrophobic, narrow cavity, whereas the terminal, gamma-carbohydrate group is solvent-exposed. The docking results indicated that the primary driving forces for digoxin binding by mAb 1B3 are hydrophobic interactions with the digoxin steroid ring system and hydrogen bonds with the digitoxose groups. The binding model accounts for the experimentally observed variations in mAb 1B3 binding affinity for various structural analogs of digoxin used previously to develop a 3D structure-activity relationship model of drug binding (Farr CD, Tabet MR, Ball WJ Jr, Fishwild DM, Wang X, Nair AC, Welsh WJ. Three-dimensional quantitative structure-activity relationship analysis of ligand binding to human sequence antidigoxin monoclonal antibodies using comparative molecular field analysis. J Med Chem 2002;45:3257-3270). In particular, the hydrogen bond pattern is consistent with the unique sensitivity of mAb 1B3's binding affinity to the number of sugar residues present in a cardiac glycoside. The hydrophobic environment about the steroid moiety of digoxin is compatible with the mAb's reduced affinity for ligands that possess hydrophilic hydroxyl and acetyl group modifications in this region. The model also indicated that most of the amino acid residues in contact with the ligand reside in or about the three complementarity determining regions (CDRs) of the heavy chain and the third CDR of the light chain. A comparison of the 1B3 binding model with the crystal structures of two murine antidigoxin mAbs revealed similar binding patterns used by the three mAbs, such as a high frequency of occurrence of aromatic, hydrophobic residues in the CDRs and a dominant role of the heavy chain CDR3 in antigen binding. PMID:15971203

Paula, Stefan; Monson, Nancy; Ball, William James

2005-08-15

47

Ischemia-induced alterations in myocardial (Na+ + K+)-ATPase and cardiac glycoside binding.  

PubMed Central

The effects of ischemia on the canine myocardial (Na+ + K+)-ATPase complex were examined in terms of alterations in cardiac glycoside binding and enzymatic activity. Ability of the myocardial cell to bind tritiated ouabain in vivo was assessed after 1, 2, and 6 h of coronary occlusion followed by 45 min of reperfusion, and correlated with measurements of in vitro (Na+ + K+)-ATPase activity and in vitro [3H]ouabain binding after similar periods of ischemia. Regional blood flow alterations during occlusion and reperfusion were simultaneously determined utilizing 15 mum radioactive microspheres to determine the degree to which altered binding of ouabain might be flow related. Anterior wall infarction was produced in 34 dogs by snaring of confluent branches of the left coronary system. Epicardial electrograms delineated ischemic and border zone areas. Coronary reperfusion after 2 and 6 h of occlusion was associated with impaired reflow of blood and markedly impaired uptake of [3H]ouabain in ischemic myocardium. In both groups, in vivo [3H]ouabain binding by ischemic tissue was reduced out of proportion to the reduction in flow. Despite near-complete restoration of flow in seven dogs occluded for 1 h and reperfused, [3H]ouabain remained significantly reduced to 58 +/- 9% of nonischemic uptake in subendocardial layers of the central zone of ischemia. Thus, when coronary flow was restored to areas of myocardium rendered acutely ischemia for 1 or more hours, ischemic zones demonstrated progressively diminished ability to bind ouabain. To determine whether ischemia-induced alteration in myocardial (Na+ + K+)-ATPase might underlie these changes, (Na+ + K+)-ATPase activity and [3H]ouabain binding were measured in microsomal fractions from ischemic myocardium after 1, 2, and 6 h of coronary occlusion. In animals occluded for 6 h, (Na+ + K+)-ATPase activity was significantly reduced by 40% in epicardial and by 35% in endocardial layers compared with nonischemic myocardium. Comparable reductions in in vitro [3H]ouabain binding were also demonstrated. Reperfusion for 45 min after occlusion for 6 h resulted in no significant restoration of enzyme activity when compared to the nonreperfused animals. In six animals occluded for 2 h, a time at which myocardial creatine phosphokinase activity remains unchanged, (Na+ + K+)-ATPase activity was reduced by 25% compared with nonischemic enzyme activity. In five dogs occluded for 1 h, (Na+ + K+)-ATPase activity in ischemic myocardium was unchanged from control levels. We conclude that reduced regional myocardial blood flow, local alterations in cellular milieu, and altered glycoside-binding properties of (Na+ + K+)-ATPase all participate in the reduction of cardiac glycoside binding observed after reperfusion of ischemic myocardium. In addition, after 2 or more hours of severe ischemia, myocardial (Na+ + K+)-ATPase catalytic activity is significantly reduced despite incubation in the presence of optimal substrate concentrations. Images

Beller, G A; Conroy, J; Smith, T W

1976-01-01

48

Arrhythmogenic adverse effects of cardiac glycosides are mediated by redox modification of ryanodine receptors  

PubMed Central

Abstract The therapeutic use of cardiac glycosides (CGs), agents commonly used in treating heart failure (HF), is limited by arrhythmic toxicity. The adverse effects of CGs have been attributed to excessive accumulation of intracellular Ca2+ resulting from inhibition of Na+/K+-ATPase ion transport activity. However, CGs are also known to increase intracellular reactive oxygen species (ROS), which could contribute to arrhythmogenesis through redox modification of cardiac ryanodine receptors (RyR2s). Here we sought to determine whether modification of RyR2s by ROS contributes to CG-dependent arrhythmogenesis and examine the relevant sources of ROS. In isolated rat ventricular myocytes, the CG digitoxin (DGT) increased the incidence of arrhythmogenic spontaneous Ca2+ waves, decreased the sarcoplasmic reticulum (SR) Ca2+ load, and increased both ROS and RyR2 thiol oxidation. Additionally, pretreatment with DGT increased spark frequency in permeabilized myocytes. These effects on Ca2+ waves and sparks were prevented by the antioxidant N-(2-mercaptopropionyl) glycine (MPG). The CG-dependent increases in ROS, RyR2 oxidation and arrhythmogenic propensity were reversed by inhibitors of NADPH oxidase, mitochondrial ATP-dependent K+ channels (mito-KATP) or permeability transition pore (PTP), but not by inhibition of xanthine oxidase. These results suggest that the arrhythmogenic adverse effects of CGs involve alterations in RyR2 function caused by oxidative changes in the channel structure by ROS. These CG-dependent effects probably involve release of ROS from mitochondria possibly mediated by NADPH oxidase.

Ho, Hsiang-Ting; Stevens, Sarah C W; Terentyeva, Radmila; Carnes, Cynthia A; Terentyev, Dmitry; Gyorke, Sandor

2011-01-01

49

Human Cytomegalovirus Inhibition by Cardiac Glycosides: Evidence for Involvement of the hERG Gene  

PubMed Central

Infection with human cytomegalovirus (HCMV) continues to be a major threat for pregnant women and the immunocompromised population. Although several anti-HCMV therapies are available, the development of new anti-HCMV agents is highly desired. There is growing interest in identifying compounds that might inhibit HCMV by modulating the cellular milieu. Interest in cardiac glycosides (CG), used in patients with congestive heart failure, has increased because of their established anticancer and their suggested antiviral activities. We report that the several CG—digoxin, digitoxin, and ouabain—are potent inhibitors of HCMV at nM concentrations. HCMV inhibition occurred prior to DNA replication, but following binding to its cellular receptors. The levels of immediate early, early, and late viral proteins and cellular NF-?B were significantly reduced in CG-treated cells. The activity of CG in infected cells correlated with the expression of the potassium channel gene, hERG. CMV infection upregulated hERG, whereas CG significantly downregulated its expression. Infection with mouse CMV upregulated mouse ERG (mERG), but treatment with CG did not inhibit virus replication or mERG transcription. These findings suggest that CG may inhibit HCMV by modulating human cellular targets associated with hERG and that these compounds should be studied for their antiviral activities.

Kapoor, Arun; Cai, Hongyi; Forman, Michael; He, Ran; Shamay, Meir

2012-01-01

50

Suppression of mouse lymphocytic mouse leukemia L1210 cells growth by cardiac glycosides  

SciTech Connect

The molecular mechanism of cytotoxic effect of cardiac glycosides is poorly understood, although their beneficial effects on certain types of tumor are well appreciated. Ouabain was tested against well characterized lymphocytic mouse leukemia L1210 cells in vitro. Logarithmically growing L1210 cells were harvested by centrifugation and incubated in a medium of RPMI 1640, 11% fetal bovine serum (pH 7.0) at 37/sup 0/C. In certain incubation bottles various doses of ouabain (10/sup -5/ M, 5 x 10/sup -5/ M and 10/sup -4/ M) were added to compare with control cell growth by counting cell number in a Coulter counter. Ouabain inhibited L1210 cell growth in drug dose dependently. The IC/sub 50/ is found to be 1 x 10/sup -5/ M. Incubation of L1210 cells with /sup 3/H-ouabain indicates that ouabain binds to the cells and diffuses into the cells, which caused cell deformation and subsequent cell death, as shown by scanning electron micrographic pictures. Ouabain also inhibited the uptake of /sup 3/H-thymidine, which will interfere with the synthesis of cell DNA. This study suggests that ouabain produces cellular cytotoxic effect by preventing the transport of thymidine or other essential ingredients for the survival of the L1210 cells.

Rhee, H.

1986-03-05

51

Identification of cardiac glycoside molecules as inhibitors of c-Myc IRES-mediated translation.  

PubMed

Translation initiation is a fine-tuned process that plays a critical role in tumorigenesis. The use of small molecules that modulate mRNA translation provides tool compounds to explore the mechanism of translational initiation and to further validate protein synthesis as a potential pharmaceutical target for cancer therapeutics. This report describes the development and use of a click beetle, dual luciferase cell-based assay multiplexed with a measure of compound toxicity using resazurin to evaluate the differential effect of natural products on cap-dependent or internal ribosome entry site (IRES)-mediated translation initiation and cell viability. This screen identified a series of cardiac glycosides as inhibitors of IRES-mediated translation using, in particular, the oncogene mRNA c-Myc IRES. Treatment of c-Myc-dependent cancer cells with these compounds showed a decrease in c-Myc protein associated with a significant modulation of cell viability. These findings suggest that inhibition of IRES-mediated translation initiation may be a strategy to inhibit c-Myc-driven tumorigenesis. PMID:23150017

Didiot, Marie-Cecile; Hewett, Jeffrey; Varin, Thibault; Freuler, Felix; Selinger, Douglas; Nick, Hanspeter; Reinhardt, Juergen; Buckler, Alan; Myer, Vic; Schuffenhauer, Ansgar; Guy, Chantale T; Parker, Christian N

2013-04-01

52

Effect of cardiac glycosides on action potential characteristics and contractility in cat ventricular myocytes: role of calcium overload.  

PubMed

There is increasing evidence that cardiac glycosides act through mechanisms distinct from inhibition of the sodium pump but which may contribute to their cardiac actions. To more fully define differences between agents indicative of multiple sites of action, we studied changes in contractility and action potential (AP) configuration in cat ventricular myocytes produced by six cardiac glycosides (ouabain, ouabagenin, dihydroouabain, actodigin, digoxin, and resibufogenin). AP shortening was observed only with ouabain and actodigin. There was extensive inotropic variability between agents, with some giving full inotropic effects before automaticity occurred whereas others produced minimal inotropy before toxicity. AP shortening was not a result of alterations in calcium current or the inward rectifier potassium current, but correlated with an increase in steady-state outward current (Iss), which was sensitive to KB-R7943, a Na+-Ca2+ exchange (NCX) inhibitor. Interestingly, Iss was observed following exposure to ouabain and dihydroouabain, suggesting that an additional mechanism is operative with dihydroouabain that prevents AP shortening. Further investigation into differences in inotropy between ouabagenin, dihydroouabain and ouabain revealed almost identical responses under AP voltage clamp. Thus all agents appear to act on the sodium pump and thereby secondarily increase the outward reverse mode NCX current, but the extent of AP duration shortening and positive inotropy elicited by each agent is limited by development of their toxic actions. The quantitative differences between cardiac glycosides suggest that mechanisms independent of sodium pump inhibition may result from an altered threshold for calcium overload possibly involving direct or indirect effects on calcium release from the sarcoplasmic reticulum. PMID:12954807

Ruch, Stuart R; Nishio, Manabu; Wasserstrom, J Andrew

2003-10-01

53

Effect of cardiac glycosides from Nerium indicum on feeding rate, digestive enzymes activity and ultrastructural alterations of hepatopancreas in Pomacea canaliculata.  

PubMed

Cardiac glycosides from Nerium indicum showed potent molluscicide activity against Pomacea canaliculata (GAS), but the toxicological mechanism is still far less understood. Effects of sublethal treatments of cardiac glycosides on feeding rate, digestive enzymes and ultrastructural alterations of the hepatopancreas in GAS were evaluated in this study. Exposure of GAS to sublethal concentrations of cardiac glycosides resulted in a significant reduction of feeding rate of GAS. The amylase, cellulose and protease activity were increase significantly at the end of 24 h followed by significant inhibition after 48 h of exposure while lipase activity was not affected significantly at the end of 24 h followed by a significant inhibition after 48 h of exposure during experimental period. The main ultrastructural alterations of hepatopancreas observed in snails under cardiac glycosides treatment comprised disruption of nuclear membrane, increased vesiculation and dilatation of endoplasmic reticulum, and vacuolization and swelling of mitochondrial compared to the untreated GAS. These results, for the first time, provide systematic evidences showing that cardiac glycosides seriously impairs the hepatopancreas tissues of GAS, resulting in inhibition of digestive enzymes activity and feeding rate and cause GAS death in the end. PMID:24361644

Dai, Lingpeng; Qian, Xiaowei; Nan, Xuyang; Zhang, Yejian

2014-01-01

54

Neovascularization of ischemic myocardium by newly isolated tannins prevents cardiomyocyte apoptosis and improves cardiac function.  

PubMed

During remodeling progress post myocardial infarction, the contribution of neoangiogenesis to the infarct-bed capillary is insufficient to support the greater demands of the hypertrophied but viable myocardium resulting in further ischemic injury to the viable cardiomyocytes at risk. Here we reported the bio-assay-guided identification and isolation of angiogenic tannins (angio-T) from Geum japonicum that induced rapid revascularization of infarcted myocardium and promoted survival potential of the viable cardiomyocytes at risk after myocardial infarction. Our results demonstrated that angio-T displayed potent dual effects on up-regulating expression of angiogenic factors, which would contribute to the early revascularization and protection of the cardiomyocytes against further ischemic injury, and inducing antiapoptotic protein expression, which inhibited apoptotic death of cardiomyocytes in the infarcted hearts and limited infarct size. Echocardiographic studies demonstrated that angio-T-induced therapeutic effects on acute infarcted myocardium were accompanied by significant functional improvement by 2 days after infarction. This improvement was sustained for 14 days. These therapeutic properties of angio-T to induce early reconstitution of a blood supply network, prevent apoptotic death of cardiomyocytes at risk, and improve heart function post infarction appear entirely novel and may provide a new dimension for therapeutic angiogenesis medicine for the treatment of ischemic heart diseases. PMID:17380192

Gu, Xuemei; Cheng, Lei; Chueng, Winghong L; Yao, Xinsheng; Liu, Hongwei; Qi, Guoqing; Li, Ming

2006-01-01

55

Quercetin provides greater cardioprotective effect than its glycoside derivative rutin on isoproterenol-induced cardiac fibrosis in the rat.  

PubMed

Quercetin exhibits numerous pharmacological effects, including the capacity for cardioprotection. This study aimed to investigate whether quercetin or its glycoside derivative rutin has any protective action against isoproterenol (ISO) induced cardiac fibrosis, and investigate the structure-activity relationship. Male Wistar rats were injected subcutaneously with ISO (15 mg·(kg body mass)(-1)) to induce experimental cardiac fibrosis. The cardioprotective effect of co-treatment with quercetin (25 or 50 mg·kg(-1)) or rutin (25 or 50 mg·kg(-1)) was investigated in ISO-induced cardiac fibrosis in rats. The administration of quercetin and rutin signifcantly decreased the cardiac weight index and myocardial enzyme activity, increased the activity of superoxide dismutase in the serum, and inhibited the ISO-induced increase in angiotensin?II and aldosterone in the plasma. Furthermore, overexpression of transforming growth factor ?1 (TGF-?1), connective tissue growth factor (CTGF), and excessive deposition of extracellular matrix (ECM) in isoproterenol-treated myocardial tissues were normalized by quercetin and rutin. Our results suggest that both quercetin and rutin exhibited cardioprotective effects in cardiac fibrosis induced by ISO in the rat heart. Moreover, the effects of rutin are weaker than quercetin at the same dose. The mechanism of these effects may be related to antioxidative stress, inhibition of the renin-angiotensin-aldosterone system, decrease in the expression of TGF-?1 and CTGF, and the subsequent reduction in the deposition of the ECM. PMID:24117263

Li, Min; Jiang, Yichuan; Jing, Wuhui; Sun, Bo; Miao, Chunsheng; Ren, Liqun

2013-11-01

56

Optimization and validation of a high-performance liquid chromatography method for the analysis of cardiac glycosides in Digitalis lanata.  

PubMed

In this study, a simple and reliable HPLC method for the qualitative and quantitative analysis of cardiac glycosides in Digitalis lanata Ehrh. raw material was developed and applied to healthy and phytoplasma-infected plants. The target analytes cover a broad range of secondary metabolites, including primary, secondary and tertiary glycosides and the corresponding aglycones. The sample preparation was carried out by sonication of the plant material with 70% (v/v) aqueous methanol at room temperature, followed by reversed-phase solid-phase extraction purification from interfering pigments. The HPLC analyses were performed on a Symmetry C(18) column (75 mm x 4.6mm I.D., 3.5 microm), with a gradient elution composed of water and acetonitrile, at a flow rate of 1.0 mL/min. The column temperature was set at 20 degrees C and the photodiode array detector monitored the eluent at 220 nm. The method was validated with respect to ICH guidelines and the validation parameters were found to be highly satisfactory. The application of the method to the analysis of D. lanata leaves indicated that air-drying was the optimum method for raw material processing when compared with freeze-drying. The analysis of healthy and phytoplasma-infected plants demonstrated that the secondary metabolite mainly affected by the pathogen presence was lanatoside C (153.2 microg/100mg versus 76.1 microg/100mg). Considering the importance of D. lanata plant material as source of cardiac glycosides, the developed method can be considered suitable for the phytochemical analysis and for the quality assurance of D. lanata used for pharmaceutical purpose. PMID:19268961

Pellati, Federica; Bruni, Renato; Bellardi, Maria Grazia; Bertaccini, Assunta; Benvenuti, Stefania

2009-04-10

57

In vitro and in vivo neuroprotective activity of the cardiac glycoside oleandrin from Nerium oleander in brain slice-based stroke models.  

PubMed

The principal active constituent of the botanical drug candidate PBI-05204, a supercritical CO(2) extract of Nerium oleander, is the cardiac glycoside oleandrin. PBI-05204 shows potent anticancer activity and is currently in phase I clinical trial as a treatment for patients with solid tumors. We have previously shown that neriifolin, which is structurally related to oleandrin, provides robust neuroprotection in brain slice and whole animal models of ischemic injury. However, neriifolin itself is not a suitable drug development candidate and the FDA-approved cardiac glycoside digoxin does not cross the blood-brain barrier. We report here that both oleandrin as well as the full PBI-05204 extract can also provide significant neuroprotection to neural tissues damaged by oxygen and glucose deprivation as occurs in ischemic stroke. Critically, we show that the neuroprotective activity of PBI-05204 is maintained for several hours of delay of administration after oxygen and glucose deprivation treatment. We provide evidence that the neuroprotective activity of PBI-05204 is mediated through oleandrin and/or other cardiac glycoside constituents, but that additional, non-cardiac glycoside components of PBI-05204 may also contribute to the observed neuroprotective activity. Finally, we show directly that both oleandrin and the protective activity of PBI-05204 are blood brain barrier penetrant in a novel model for in vivo neuroprotection. Together, these findings suggest clinical potential for PBI-05204 in the treatment of ischemic stroke and prevention of associated neuronal death. PMID:21950737

Dunn, Denise E; He, Dong Ning; Yang, Peiying; Johansen, Mary; Newman, Robert A; Lo, Donald C

2011-11-01

58

The time courses of the changes in contractile force and in transmembrane potentials induced by cardiac glycosides in guinea-pig papillary muscle  

PubMed Central

1. The effects of ouabain, digoxin, digoxigenin monodigitoxoside, digoxigenin bisdigitoxoside and digitoxigenin bisdigitoxoside on the force of contraction and on the transmembrane action potential were compared in isolated papillary muscles of guinea-pigs. 2. All cardiac glycosides studied had a dose-dependent positive inotropic effect and simultaneously shortened the duration of the action potential at all levels of repolarization from the start of drug action. 3. In every instance, the reduction of the action potential duration developed more slowly than the increment in contractile force. However, the ratios between the two rates were independent of the concentrations used and seemed to be characteristic for the individual cardiac glycosides. 4. All cardiac glycosides had a biphasic effect on the time-to-peak tension. An initial increase was followed by a dose-dependent decrease. 5. The results are discussed with respect to the possible sites of action. Taking into account the different rates as well as the different ratios, it is proposed that more than one site of action is involved in producing the different effects of cardiac glycosides on heart muscle.

Lullmann, H.; Ravens, Ursula

1973-01-01

59

Effects of AL 107, a novel semisynthetic cardiac glycoside, on the cardiovascular system in anaesthetized beagle dogs with pentobarbital-induced cardiac insufficiency.  

PubMed

The inotropic efficacy, arrhythmogenicity and cardiohaemodynamic properties of AL 107 (3-alpha-methyl-digitoxigenin glucoside, CAS 62190-59-4), a novel cardiac glycoside, were studied in anaesthetized dogs with pentobarbital-induced acute cardiac insufficiency. Three groups of dogs received AL 107, ouabain or verhicle. The cardiac glycosides were infused intravenously in eight increasing dose levels which where given cumulatively. Slope of left ventricular pressure rise (LVdp/dtmax) increased in the AL 107- and ouabain-treated groups. At the end of the 6th dose level ouabain caused a significantly higher LVdp/dtmax (137 +/- 15% of the baseline value taken before induction of insufficiency) than AL 107 (94 +/- 9%). Further increase of the dose resulted in a reduction of LVdp/dtmax in ouabain-treated dogs, whereas AL 107 continuously increased LVdp/dtmax up to the highest dose infused, where 130 +/- 16% of the baseline value was reached. In ouabain-treated dogs, ECG abnormalities accompanied the decrease of LVdp/dtmax whereas ECG-changes did not interfere with the development of left ventricular contractility in AL 107-treated dogs. The 6th dose of ouabain provoked a maximal increase of cardiac output (CO) (up to 107 +/- 8% of baseline values) and stroke volume (SV) (up to 122 +/- 6% of baseline values) which decreased upon further dose elevation. In the dose-range studied AL-107 induced a continuous increase of both parameters which, however, hardly reached the baseline values. ECG abnormalities occurred in both substance-treated groups and showed quantitative but not qualitative differences. The ECG showed rapid recovery after cessation of AL 107 infusion but did not normalize during a postinfusional recovery period of 1 h after treatment with ouabain. In conclusion, AL 107 increased cardiac performance in an acute canine model of cardiac insufficiency. It was slightly less active than ouabain. However, the ECG disorders were more moderate in AL 107--than in ouabain-treated dogs, a difference which was most pronounced with respect to reversibility in the postinfusional period. PMID:10483514

Kögel, B; Schneider, J; Gleitz, J; Wilffert, B; Peters, T

1999-08-01

60

A novel high-pressure liquid-liquid extraction process for downstream processing in biotechnology: extraction of cardiac glycosides.  

PubMed

This investigation examines phase equilibrium phenomena that can be used to create two water-like solvents for liquid-liquid extraction in downstream processing in biotechnology: a completely miscible, binary liquid mixture of water and a hydrophilic organic solvent (e. g., an alcohol) reveals a liquid phase split, when it is pressurized with a "near-critical" gas (i.e., a substance which at ambient conditions is a gas, near its critical temperature). This phase split results in two hydrophilic liquid phases. Making use of this phenomenon in process development first requires research on the phase split phenomenon and, second, research on the feasibility of biomolecule extraction and separation. In this study, basic fluid phase equilibrium phenomena are briefly described. Then, experimental results are reported for the partitioning of small amounts of cardiac glycosides (digitoxin and digoxin) on coexisting liquid phases in the high-pressure, three-phase, vapor-liquid-liquid equilibrium of the ternary system of "near critical" CO(2) + water + 1-propanol, at 313 K and 333 K. Finally, a process for extraction and separation of the aforementioned glycosides by means of the high-pressure phase equilibrium phenomenon is discussed. PMID:10898865

Adrian, T; Freitag, J; Maurer, G

2000-09-01

61

Cardiac glycoside ouabain induces autophagic cell death in non-small cell lung cancer cells via a JNK-dependent decrease of Bcl-2.  

PubMed

Cardiac glycosides are Na/K-ATPase inhibitors, clinically used for congestive heart failure and cardiac arrhythmias. Epidemiological studies have reported that patients on cardiac glycosides treatment are protected from some types of cancers. This evidence together with the demonstration that cardiac glycosides show selective cytotoxicity against cancer cells has raised new interest on the anticancer properties of these drugs. This study examines the mechanism involved in the anticancer effect of ouabain in non-small cell lung cancer cells lines (A549 and H1975). Ouabain inhibited cell proliferation and induced cell death in a concentration-dependent manner. Cell death was caspase-independent and showed classical patterns of autophagic cell death: conversion of LC3-I to LC3-II, increase of LC3 puncta and increase of autophagic flux. Moreover, cell death was completely blocked by the class III phosphatidylinositol-3 kinase inhibitor 3-methyladenine. Here we show that ouabain caused the reduction of Bcl-2 protein levels, with no change in the expression of the autophagic protein Beclin 1. Early signalling events of ouabain exposure were ERK1/2 and JNK activation, however only JNK inhibition with SP600125 or JNK knockdown by shRNA were able to prevent Bcl-2 decrease, conversion of LC3-I to LC3-II and cell death. We propose that JNK activation by ouabain leads to a decrease of Bcl-2 levels, resulting in disruption of the inhibitory interaction of Bcl-2 with Beclin 1, that promotes autophagy. These findings indicate that pharmacological modulation of autophagy by cardiac glycosides could be exploited for anticancer therapy. PMID:24630927

Trenti, Annalisa; Grumati, Paolo; Cusinato, Federico; Orso, Genny; Bonaldo, Paolo; Trevisi, Lucia

2014-05-15

62

Glycoside vs. Aglycon: The Role of Glycosidic Residue in Biological Activity  

NASA Astrophysics Data System (ADS)

A large number of biologically active compounds are glycosides. Sometimes the glycosidic residue is crucial for their activity, in other cases glycosylation only improves pharmacokinetic parameters. Recent developments in molecular glycobiology brought better understanding of aglycon vs. glycoside activities, and made possible the development of new, more active or more effective glycodrugs based on these findings - a very illustrative recent example is vancomycin. The new enzymatic methodology "glycorandomization" enabled preparation of glycoside libraries and opened up paths to the preparation of optimized or entirely novel glycoside antibiotics. This chapter deals with an array of glycosidic compounds currently used in medicine but also covers the biological activity of some glycosidic metabolites of known drugs. The chapter discusses glycosides of vitamins, polyphenolic glycosides (flavonoids), alkaloid glycosides, glycosides of antibiotics, glycopeptides, cardiac glycosides, steroid and terpenoid glycosides etc. The physiological role of the glycosyl moiety and structure-activity relations (SAR) in the glycosidic moiety (-ies) are also discussed.

K?en, Vladimír

63

Cardiac glycosides and the risk of breast cancer in women with chronic heart failure and supraventricular arrhythmia.  

PubMed

The aim of this study is to determine whether the use of cardiac glycosides (CGs), drugs used in the treatment of congestive heart failure (CHF) and supra-ventricular arrhythmia, is associated with an increased risk of breast cancer. A cohort of 53,454 women newly diagnosed with CHF or supra-ventricular arrhythmia between January 1, 1988 and December 31, 2010, followed until December 31, 2012, was identified using the United Kingdom Clinical Practice Research Datalink. A nested case-control analysis was performed, where all incident cases of breast cancer occurring during follow-up were identified and matched with up to 10 controls on age, cohort entry date, and duration of follow-up. Conditional logistic regression models were used to estimate adjusted odds ratios (ORs) with 95 % confidence intervals (CIs) of incident breast cancer associated with the use of CGs, along with measures of cumulative duration of use and dose. All analyses considered a one year lag period prior to the event, necessary for latency considerations and to minimize detection bias. The 898 breast cancer cases diagnosed beyond one year of follow-up were matched to 8,940 controls. Overall, use of CGs was not associated with an increased risk of breast cancer when compared to non-use (OR 1.07, 95 % CI 0.90-1.26). Furthermore, the risk did not vary with cumulative duration of use or cumulative dose. The findings of this large population-based study indicate that the use of CGs is not associated with an increased risk of breast cancer. This should provide reassurance to physicians and patients using these drugs. PMID:25038879

Couraud, Sébastien; Dell'Aniello, Sophie; Bouganim, Nathaniel; Azoulay, Laurent

2014-08-01

64

Advances in understanding the role of cardiac glycosides in control of sodium transport in renal tubules.  

PubMed

Cardiotonic steroids have been used for the past 200 years in the treatment of congestive heart failure. As specific inhibitors of membrane-bound Na(+)/K(+) ATPase, they enhance cardiac contractility through increasing myocardial cell calcium concentration in response to the resulting increase in intracellular Na concentration. The half-minimal concentrations of cardiotonic steroids required to inhibit Na(+)/K(+) ATPase range from nanomolar to micromolar concentrations. In contrast, the circulating levels of cardiotonic steroids under physiological conditions are in the low picomolar concentration range in healthy subjects, increasing to high picomolar levels under pathophysiological conditions including chronic kidney disease and heart failure. Little is known about the physiological function of low picomolar concentrations of cardiotonic steroids. Recent studies have indicated that physiological concentrations of cardiotonic steroids acutely stimulate the activity of Na(+)/K(+) ATPase and activate an intracellular signaling pathway that regulates a variety of intracellular functions including cell growth and hypertrophy. The effects of circulating cardiotonic steroids on renal salt handling and total body sodium homeostasis are unknown. This review will focus on the role of low picomolar concentrations of cardiotonic steroids in renal Na(+)/K(+) ATPase activity, cell signaling, and blood pressure regulation. PMID:24781255

Khundmiri, Syed Jalal

2014-07-01

65

The electrogenic sodium pump in guinea-pig ventricular muscle: inhibition of pump current by cardiac glycosides.  

PubMed

1. The inhibition of the electrogenic sodium pump in guinea-pig ventricular muscle by cardiac glycosides was studied with a voltage-clamp technique.2. Superfusion of the preparation with dihydro-ouabain (DHO) produced a reversible depolarization of up to 7 mV. When the membrane potential was clamped to a constant value near the resting potential application of DHO produced a corresponding current change in the inward direction which reached a steady state in less than 1 min.3. The drug-induced current change (I(D)) was found to be the result of a parallel shift of the current-voltage relation. The contributions of a change in extracellular K or intracellular Na to the measured I(D) were shown to be very small. From these findings and the results summarized below it was concluded that I(D) represents the blockage of the electrogenic pump current by DHO and that it is proportional to the number of drug molecules bound to the Na-K-ATPase in the intact cell.4. The dependence of I(D) on the concentration of DHO applied (5 x 10(-6)-8 x 10(-4) M) was found to be consistent with the predictions of the law of mass action for reversible one-to-one binding of the drug to the Na-K pump under equilibrium conditions. From a Scatchard-type plot the equilibrium dissociation constant (K(D)) of DHO was determined to be 4.6 (+/-2.3) x 10(-5) M.5. The steady-state pump current in the resting preparation was calculated to be 0.81+/-0.26 muA/cm(2). It contributed 6.4+/-0.9 mV to the resting potential in Tyrode solution containing 3 mM-K.6. In the smallest preparations used the measured time course of the onset and decay of I(D) agreed with the chemical kinetics of binding and unbinding calculated for various DHO concentrations. The rate constant of unbinding (k(2)) was found to be 3.4 (+/-0.7) x 10(-2) S(-1) and the average rate constant of binding (k(1)) was 7.4 x 10(2) M(-1) S(-1).7. By comparing the effects of ouabain and DHO in the same preparation the following estimates of the chemical constants of ouabain binding to the Na-K pump were obtained: K(D) approximately 1.5 x 10(-6) M; k(1) approximately 4 x 10(3) M(-1) S(-1); k(2) approximately 6 x 10(-3) S(-1).8. An analysis of the transmembrane movements of Na and K in the steady state showed that the measured pump current density is consistent with a counter-transport of 3 Na and 2 K ions. PMID:6294287

Daut, J; Rüdel, R

1982-09-01

66

Does Propolis Contain Tannins?  

PubMed Central

Although polyphenols have been reported as common constituents of propolis, tannins have rarely been mentioned as its constituents. Propolis samples from seven localities in Brazil were analyzed for detection of proanthocyanidins (condensed tannins) and determination of the tannin content. Positive reaction for proanthocyanidins was observed for all samples tested. The contents of tannins varied in the range 0.6–4.1%. A high degree of correlation was noted between total phenols and tannin content. Red and green propolis contained high contents of tannins, while in brown propolis the content was lower. It is suggested that the contents of tannins should be a parameter to be considered in propolis characterization.

Mayworm, Marco A. S.; Lima, Carolina A.; Tomba, Augusto C. B.; Fernandes-Silva, Caroline C.; Salatino, Maria L. F.

2014-01-01

67

Does propolis contain tannins?  

PubMed

Although polyphenols have been reported as common constituents of propolis, tannins have rarely been mentioned as its constituents. Propolis samples from seven localities in Brazil were analyzed for detection of proanthocyanidins (condensed tannins) and determination of the tannin content. Positive reaction for proanthocyanidins was observed for all samples tested. The contents of tannins varied in the range 0.6-4.1%. A high degree of correlation was noted between total phenols and tannin content. Red and green propolis contained high contents of tannins, while in brown propolis the content was lower. It is suggested that the contents of tannins should be a parameter to be considered in propolis characterization. PMID:24959188

Mayworm, Marco A S; Lima, Carolina A; Tomba, Augusto C B; Fernandes-Silva, Caroline C; Salatino, Maria L F; Salatino, Antonio

2014-01-01

68

Differential photoaffinity labeling of catalytic subunits of NaK-ATPase with carrier-free ¹²⁵I-cardiac glycosides  

Microsoft Academic Search

The authors have obtained evidence for structural differences in the cardiac glycoside binding site between the ..cap alpha.. and ..cap alpha..(+) forms of the catalytic subunit of NaK-ATPase, using three closely related photoaffinity derivatives of the cardiotonic steroid, digitoxigenin. (¹²⁵I)N-(p-azido-m-iodo-o-hydroxybenzoyl)-4-amino-4,6-dideoxy-galactosyl digitoxigenin (IA-GaD), (¹²⁵I)N-(3-(p-azido-m-iodophenyl)-propionyl)-4-amino-4,6-dideoxy-ga-lactosyl digitoxigenin (AIPP-GaD) and (¹²⁵I)N-(3-(p-azido-m-iodophenyl)-propionyl)-4-amino-4,6-dideoxy-glucosyl digitoxi-genin (AIPP-GluD) were synthesized. AIPP-GaD and AIPP-GluD are stereoisomers. Eel electroplax and dog

J. Lowndes; M. Hokin-Neaverson; A. Ruoho

1986-01-01

69

Comprehensive transcriptome analysis reveals novel genes involved in cardiac glycoside biosynthesis and mlncRNAs associated with secondary metabolism and stress response in Digitalis purpurea  

PubMed Central

Abstract Background Digitalis purpurea is an important ornamental and medicinal plant. There is considerable interest in exploring its transcriptome. Results Through high-throughput 454 sequencing and subsequent assembly, we obtained 23532 genes, of which 15626 encode conserved proteins. We determined 140 unigenes to be candidates involved in cardiac glycoside biosynthesis. It could be grouped into 30 families, of which 29 were identified for the first time in D. purpurea. We identified 2660 mRNA-like npcRNA (mlncRNA) candidates, an emerging class of regulators, using a computational mlncRNA identification pipeline and 13 microRNA-producing unigenes based on sequence conservation and hairpin structure-forming capability. Twenty five protein-coding unigenes were predicted to be targets of these microRNAs. Among the mlncRNA candidates, only 320 could be grouped into 140 families with at least two members in a family. The majority of D. purpurea mlncRNAs were species-specific and many of them showed tissue-specific expression and responded to cold and dehydration stresses. We identified 417 protein-coding genes with regions significantly homologous or complementary to 375 mlncRNAs. It includes five genes involved in secondary metabolism. A positive correlation was found in gene expression between protein-coding genes and the homologous mlncRNAs in response to cold and dehydration stresses, while the correlation was negative when protein-coding genes and mlncRNAs were complementary to each other. Conclusions Through comprehensive transcriptome analysis, we not only identified 29 novel gene families potentially involved in the biosynthesis of cardiac glycosides but also characterized a large number of mlncRNAs. Our results suggest the importance of mlncRNAs in secondary metabolism and stress response in D. purpurea.

2012-01-01

70

Potassium changes the relationship between receptor occupancy and the inotropic effect of cardiac glycosides in guinea-pig myocardium.  

PubMed Central

K+ (2.4-15.6 mmol l-1) antagonized the positive inotropic effect of dihydro-ouabain. The concentration-effect curves became steeper with the shift to higher concentrations of the glycoside. At 1.2 mmol l-1 Ca2+, an increase in K+ from 2.4 to 12 mmol l-1 required tenfold higher concentrations of dihydro-ouabain to produce equal inotropic effects. This factor was reduced to four at 3.2 mmol l-1 Ca2+. The same change in K+ concentration, at 1.2 mmol l-1 Ca2+, diminished the inotropic effect of ouabain on rested-state contractions by a factor of six. The positive inotropic effect of Ca2+ was also antagonized by K+ (1.2-12 mmol l-1). Reduction of Na+ from 140 to 70 mmol l-1 abolished the antagonistic action of K+ (1.2-8.0 mmol l-1). Moreover the inotropic effect of Ca2+ was enhanced. Reduction of Na+, from 140 to 70 mmol l-1, antagonized the positive inotropic effect of dihydro-ouabain more at low (2.4 mmol l-1) than at high (8.0 mmol l-1) K+. Accordingly, the extent of the dihydro-ouabain-K+ antagonism was reduced. When the K+ concentration was increased from 2.4 to 12 mmol l-1, [3H]-ouabain binding was reduced by a factor of three. This is less than the reduction in the inotropic effectiveness of ouabain or dihydro-ouabain. Reduction of stimulation frequency from 1 to 0.1215 Hz did not significantly alter the antagonistic effect of K+. Diminution of Vmax of the action potential was observed only at K+ concentrations greater than 5.9 mmol l-1, whereas the resting membrane potential was continuously depolarized over the entire range of K+ concentrations. The results support the view that the reduction in receptor affinity cannot be the sole cause of the antagonism between the glycoside and K+. Impairment of passive Na+ influx during diastole, due to the K+-dependent depolarization of the resting membrane potential, contributed to about one half of the glycoside-K+ antagonism.

Bachmaier, A.; Ebner, F.; Reiter, M.

1985-01-01

71

Proceraside A, a new cardiac glycoside from the root barks of Calotropis procera with in vitro anticancer effects.  

PubMed

We have studied the ethyl acetate fraction of the methanolic extract of the root barks of Calotropis procera (Asclepiadaceae) from Egypt. Bioassay-directed fractionation and final purification of the extract resulted in the identification of a new cardenolide glycoside named proceraside A (1) together with two known compounds, frugoside (2) and calotropin (3). Their structures were elucidated by extensive NMR studies and mass spectrometric data. The in vitro cytotoxicity of the isolated compounds was evaluated against A549 non-small cell lung cancer, U373 glioblastoma and PC-3 prostate cancer cell lines. They showed potent activity against the tested cancer cell lines with IC50 ranging from 0.005 to 0.3 ?g/mL. Cisplatin was used as positive control. PMID:24678783

Ibrahim, S R M; Mohamed, G A; Shaala, L A; Moreno, L; Banuls, Y; Kiss, R; Youssef, D T A

2014-09-01

72

Interactions between cardiac glycosides and sodium/potassium-ATPase: three-dimensional structure-activity relationship models for ligand binding to the E2-Pi form of the enzyme versus activity inhibition.  

PubMed

Sodium/potassium-ATPase (Na/K-ATPase) is a transmembrane enzyme that utilizes energy gained from ATP hydrolysis to transport sodium and potassium ions across cell membranes in opposite directions against their chemical and electrical gradients. Its transport activity is effectively inhibited by cardiac glycosides, which bind to the extracellular side of the enzyme and are of significant therapeutic value in the treatment of congestive heart failure. To determine the extent to which high-affinity binding of cardiac glycosides correlates with their potency in inhibiting pump activity, we determined experimentally both the binding affinities and inhibitory potencies of a series of 37 cardiac glycosides using radioligand binding and ATPase activity assays. The observed variations in key structural elements of these compounds correlating with binding and inhibition were analyzed by comparative molecular similarity index analysis (CoMSIA), which allowed a molecular level characterization and comparison of drug-Na/K-ATPase interactions that are important for ligand binding and activity inhibition. In agreement with our earlier comparative molecular field analysis studies [Farr, C. D., et al. (2002) Biochemistry 41, 1137-1148], the CoMSIA models predicted favorable inhibitor interactions primarily at the alpha-sugar and lactone ring moieties of the cardiac glycosides. Unfavorable interactions were located about the gamma-sugar group and at several positions about the steroid ring system. Whereas for most compounds a correlation between binding affinity and inhibitory potency was found, some notable exceptions were identified. Substitution of the five-membered lactone of cardenolides with the six-membered lactone of bufadienolides caused binding affinity to decline but inhibitory potency to increase. Furthermore, while the removal of ouabain's rhamnose moiety had little effect on inhibitory potency, it caused a dramatic decline in ligand binding affinity. PMID:15641774

Paula, Stefan; Tabet, Michael R; Ball, William James

2005-01-18

73

Mechanism of Cardioprotective Effect of Adenocine and Non-Glycoside Cardiotonic Drugs during Experimental Chronic Cardiac Insufficiency  

Microsoft Academic Search

The therapeutic action of adenocine during cardiac insufficiency (heart failure) caused by ischemic (stenosis) or reperfusion\\u000a (removal of ligature) injury to the myocardium prevents depletion of ATP, the major energy source for myocytes in the right\\u000a and left ventricles, and a drop in NAD\\/NADH ratio. The development of energy shortage during heart failure cannot be eliminated\\u000a by ?-acetyldigoxin, levosimendan, or

G. V. Sukoyan; N. V. Gongadze

2011-01-01

74

Cardiac glycosides correct aberrant splicing of IKBKAP-encoded mRNA in familial dysautonomia derived cells by suppressing expression of SRSF3.  

PubMed

The ability to modulate the production of the wild-type transcript in cells bearing the splice-altering familial dysautonomia (FD) causing mutation in the IKBKAP gene prompted a study of the impact of a panel of pharmaceuticals on the splicing of this transcript, which revealed the ability of the cardiac glycoside digoxin to increase the production of the wild-type, exon-20-containing, IKBKAP-encoded transcript and the full-length I?B-kinase-complex-associated protein in FD-derived cells. Characterization of the cis elements and trans factors involved in the digoxin-mediated effect on splicing reveals that this response is dependent on an SRSF3 binding site(s) located in the intron 5' of the alternatively spliced exon and that digoxin mediates its effect by suppressing the level of the SRSF3 protein. Characterization of the digoxin-mediated effect on the RNA splicing process was facilitated by the identification of several RNA splicing events in which digoxin treatment mediates the enhanced inclusion of exonic sequence. Moreover, we demonstrate the ability of digoxin to impact the splicing process in neuronal cells, a cell type profoundly impacted by FD. This study represents the first demonstration that digoxin possesses splice-altering capabilities that are capable of reversing the impact of the FD-causing mutation. These findings support the clinical evaluation of the impact of digoxin on the FD patient population. PMID:23711097

Liu, Bo; Anderson, Sylvia L; Qiu, Jinsong; Rubin, Berish Y

2013-08-01

75

Studies of Tannin Formaldehyde Adhesives.  

National Technical Information Service (NTIS)

Tannins are organic complex compounds generally used for tanning different kinds of leather in tanneries. Although there are numerous uses of tannins, the present study is mainly concerned with the preparation of adhesives from tannins. Different solvent ...

M. M. Anwer

1985-01-01

76

Differential photoaffinity labeling of catalytic subunits of NaK-ATPase with carrier-free /sup 125/I-cardiac glycosides  

SciTech Connect

The authors have obtained evidence for structural differences in the cardiac glycoside binding site between the ..cap alpha.. and ..cap alpha..(+) forms of the catalytic subunit of NaK-ATPase, using three closely related photoaffinity derivatives of the cardiotonic steroid, digitoxigenin. (/sup 125/I)N-(p-azido-m-iodo-o-hydroxybenzoyl)-4-amino-4,6-dideoxy-galactosyl digitoxigenin (IA-GaD), (/sup 125/I)N-(3-(p-azido-m-iodophenyl)-propionyl)-4-amino-4,6-dideoxy-ga-lactosyl digitoxigenin (AIPP-GaD) and (/sup 125/I)N-(3-(p-azido-m-iodophenyl)-propionyl)-4-amino-4,6-dideoxy-glucosyl digitoxi-genin (AIPP-GluD) were synthesized. AIPP-GaD and AIPP-GluD are stereoisomers. Eel electroplax and dog kidney NaK-ATPase (..cap alpha.. form) and rat brain synaptosomes (rich in ..cap alpha..(+) form) were photolabelled and then analyzed by SDS-PAGE and autoradiography. Photolysis with either carrier-free IA-GaD or AIPP-GluD gave ouabain-protectable labelling of NaK-ATPase catalytic subunit from all three tissues. However, photolysis with AIPP-GaD showed protectable labelling of the enzyme from eel and kidney but not from brain. This suggests a structural difference in the ..cap alpha..(+) form which results in either an inability to bind AIPP-GaD, or, perhaps more likely, an absence of a photoinsertion site in the correct location in the ..cap alpha..(+) form, as compared with the ..cap alpha.. form. It is of interest that the labelling pattern of the enzyme in the human erythrocyte resembles that of the brain enzyme.

Lowndes, J.; Hokin-Neaverson, M.; Ruoho, A.

1986-05-01

77

Influence of the cardiac glycoside digoxin on cardiac troponin I, acid-base and electrolyte balance, and haematobiochemical profiles in healthy donkeys (Equus asinus)  

PubMed Central

Background The effect of digoxin administration on the serum concentration of the cardiac troponin I (cTnI) has not been reported to date in equidae. This study was therefore designed to evaluate the effect of digoxin on cardiac cell damage in donkeys (Equus asinus) as assessed by cTnI, acid–base and electrolyte balance and haematobiochemical profiles. Ten clinically healthy donkeys were given an IV infusion of digoxin at a dose of 14 ?g/kg. Blood samples were collected from the donkeys up through 72 h post-injection. Results Three of the donkeys exhibited increased heart and respiratory rates post-injection. In the other seven animals, the heart and respiratory rates were lower 4 h post-injection. The serum digoxin concentration increased significantly at many time points after injection. The serum concentration of cTnI did not differ significantly between pre- and post-injection. An increase in blood pH was noted at 3 h after digoxin injection. There were also increases in PO2 and in oxygen saturation. Decreases in PCO2 at 2 to 48 h post-injection as well as a decrease in blood lactate at 4 h post-injection were observed. The serum concentration of glucose remained significantly elevated at all-time points after digoxin injection. Conclusions It is concluded that administration of digoxin to healthy donkeys (14 ?g/kg) did not result in elevations of serum cTnI concentration, signs of digoxin intoxication, ECG abnormalities and did not increase serum concentrations of blood urea nitrogen and creatinine.

2014-01-01

78

Oleic and linoleic acids are active principles in Nigella sativa and stabilize an E(2)P conformation of the Na,K-ATPase. Fatty acids differentially regulate cardiac glycoside interaction with the pump.  

PubMed

Nigella sativa seed oil was found to contain a modulator of Na,K-ATPase. Separation analyses combined with (1)H NMR and GCMS identified the inhibitory fraction as a mixture of oleic and linoleic acids. These two fatty acids are specifically concentrated in several medicinal plant oils, and have particularly been implicated in decreasing high blood pressure. The ouabain binding site on Na,K-ATPase has also been implicated in blood pressure regulation. Thus, we aimed to determine how these two molecules modify pig kidney Na,K-ATPase. Oleic and linoleic acids did not modify reactions involving the E(1) (Na(+)) conformations of the Na,K-ATPase. In contrast, K(+) dependent reactions were strongly modified after treatment. Oleic and linoleic acids were found to stabilize a pump conformation that binds ouabain with high affinity, i.e., an ion free E(2)P form. Time-resolved binding assays using anthroylouabain, a fluorescent ouabain analog, revealed that the increased ouabain affinity is unique to oleic and linoleic acids, as compared with ?-linolenic acid, which decreased pump-mediated ATP hydrolysis but did not equally increase ouabain interaction with the pump. Thus, the dynamic changes in plasma levels of oleic and linoleic acids are important in the modulation of the sensitivity of the sodium pump to cardiac glycosides. Given the possible involvement of the cardiac glycoside binding site on Na,K-ATPase in the regulation of hypertension, we suggest oleic acid to be a specific chaperon that modulates interaction of cardiac glycosides with the sodium pump. PMID:21767529

Mahmmoud, Yasser A; Christensen, S Brøgger

2011-10-01

79

Effects of cotton condensed tannin, maysin (Corn) and pinitol (soybeans) on Heliothis zea growth and development  

Microsoft Academic Search

Maysin, a flavone glycoside from corn silks, inhibits ingestion, and thus growth, ofHeliothis zea (Boddie) larvae. Pinitol from soybeans inhibitedH. zea growth by the same mechanism. Despite the widely held assumption that tannins inhibit growth by inhibiting assimilation, cotton condensed tannin inhibitedH. zea growth by reducing ingestion; no evidence was found for a reduction in assimilation. Neonate larvae are shown

John C. Reese; Bock G. Chan; Anthony C. Waiss

1982-01-01

80

Cardiotonic action of two tannins  

PubMed Central

A tannin isolated from Paullinia pinnata Linn., and tannic acid, have cardiotonic actions on the isolated perfused frog heart. Paullinia tannin is more firmly “fixed” than tannic acid. Tannin solutions contain peroxide, but the cardiotonic action is not dependent on this, since drugs believed to prevent peroxide formation, and sodium pyruvate which destroys peroxides, do not prevent the cardiotonic action. Maximal stimulation by tannin greatly reduces subsequent stimulation by ouabain. If calcium is omitted from the Ringer solution tannins cannot stimulate the heart. In this respect they differ from ouabain. However, the ouabain stimulation can be prevented by prior perfusion with tannin. It is suggested that the antagonism between tannin and ouabain is due to the former preventing ouabain from reaching its receptor sites, and that tannin stimulation is dependent on the formation of a calcium-tannin complex at the heart surface. In the isolated perfused mammalian heart preparation tannins increase diastolic tonus and coronary flow.

Broadbent, J. L.

1962-01-01

81

Saliva tannin interactions.  

PubMed

Many plant foods contain tannins, compounds that bind proteins, such as mammalian enzymes. Although described as tasteless, tannins can be detected orally by their astringency. However, the actual mechanism of oral detection and the effect of tannins on mastication and swallowing have been little investigated. Here, we show from in vitro tests that tannic acid, a common standard in tests used to detect tannins, significantly reduces the lubricating qualities of human saliva both by decreasing its viscosity and increasing friction, both factors lending support to the notion that astringency is a tactile phenomenon. From the literature, it is clear that this effect depends on the presence of salivary proline-rich proteins (PRP). In a mammalian context, ingestion of tannin-rich foods in a species with salivary PRP will be signalled by interference with bolus formation during mastication while the increase in friction may also be detectable and lead to increased tooth wear if the signal is ignored. In a human context, cross-cultural preferences for tannin-rich beverages such as tea, coffee and red wine at the end of meals may be explained by reduction in adhesion of food particles to the oral mucosa allowing their rapid oral clearance. PMID:11106991

Prinz, J F; Lucas, P W

2000-11-01

82

[Repeated unexplained cardiac glycoside poisoning].  

PubMed

One of the major tasks of psychiatry, suicide risk assessment, is supposed to reduce morbidity and mortality. However, assessing suicide risk can be quite challenging because it depends almost entirely upon subjective clinical judgment. The patient is often ambivalent towards committing suicide and may conceal his or her real intentions. Therefore, identification of suicidal intention may be daunting even after thorough, repeated psychiatric evaluations. Hence, clinicians must always maintain a high level of doubt, and act accordingly. In the following report we describe the case of a young man who acted out several concealed and very severe suicide attempts that put his Life at risk. Lacking any apparent risk factors, and due to prolonged efforts to cover up his actions, true evaluation and exposure of suicidal risk was extremely difficult. This case study is reported with the goal of emphasizing the complexity of suicide assessment and the need to frequently re-examine one's findings. PMID:24416817

Raveh, Yuval; Child, Omer Bonne

2013-11-01

83

Phenolics, fibre, alkaloids, saponins, and cyanogenic glycosides in a seasonal cloud forest in India  

Microsoft Academic Search

We investigated secondary compounds in ephemeral and non-ephemeral parts of trees and lianas of a seasonal cloud forest in the Western Ghats of India. We measured astringency, phenolic content, condensed tannins, gallotannins, ellagitannins, and fibre, and also screened for alkaloids, saponins and cyanogenic glycosides in 271 plant parts across 33 tree and 10 liana species which constituted more than 90%

S Mali; R. M Borges

2003-01-01

84

Analysis of condensed tannins: a review  

Microsoft Academic Search

Plant condensed tannins (proanthocyanidins, PAs) have both positive and negative effects on feed digestibility and animal performance, depending both on the quantity and biological activity of the tannins that are present. In this review, the chemistry and analysis of condensed tannins (PAs) are examined. Our first focus is on the complexity of the structures of condensed tannins and our second

P Schofield; D. M Mbugua; A. N Pell

2001-01-01

85

Plant cyanogenic glycosides  

Microsoft Academic Search

The cyanogenic glycosides belong to the products of secondary metabolism, to the natural products of plants. These compounds are composed of an ?-hydroxynitrile type aglycone and of a sugar moiety (mostly d-glucose). The distribution of the cyanogenic glycosides (CGs) in the plant kingdom is relatively wide, the number of CG-containing taxa is at least 2500, and a lot of such

János Vetter

2000-01-01

86

Glycosides from Stevia rebaudiana  

Microsoft Academic Search

A new laboratory method for isolating the glycosides stevioside and rebaudiosides A and C from leaves of Stevia rebaudiana was proposed. According to HPLC, the glycoside contents in plants grown in Russia (Voronezh Oblast’) and Ukraine (Crimea)\\u000a were 5–6% (stevioside) and 0.3–1.3% (rebaudiosides A and C).

G. I. Kovylyaeva; G. A. Bakaleinik; I. Yu. Strobykina; V. I. Gubskaya; R. R. Sharipova; V. A. Al’fonsov; V. E. Kataev; A. G. Tolstikov

2007-01-01

87

Bioactive glycosides from Chinese medicines.  

PubMed

Glycosides are the bioactive components of many famous Chinese medicines. Here reported are some bioactive glycosides we discovered from Chinese medicines in recent years. (1) Phenolic glycosides from Chinese medicines: Gastrodia elata, Aconitum austroyunanense and Helicia erratica, three bioactive phenolic glycosides were discovered and two of them have been developed into new drugs. (2) Terpenoidal glycosides: a) Monoterpenoid: the sweroside from Swertia moleensis has been developed into an anti-hepatitis drug; b) Diterpenoid: Phlomis betonicoides contains sweet glycosides; c) Triterpenoid: many biologically active triterpenoid glycosides were isolated from Panax plants and Siraitia grosvenorii. (3) Steroidal glycosides: a) C21-steroid: Cynanchum otophyllum and C. atratrum contain anti-epilepsy and anti-tumor glycosides; b) C27-steroid Hemostatic saponins were found in Paris polyphylla. PMID:1842007

Zhou, J

1991-01-01

88

Tannin Adhesives - From Laboratory to Industry.  

National Technical Information Service (NTIS)

The past research program on tannin-based adhesives, the research achievements attained and their translation into industrial application, as well as cost and technical advantages of tannin adhesives in current industrial use are discussed. In particular,...

H. O. Scharfetter A. Pizzi

1981-01-01

89

Extraction and TLC Desitometric Determination of Triterpenoid Acids (Arjungenin, Arjunolic Acid) from Terminalia arjuna Stem Bark Without Interference of Tannins  

Microsoft Academic Search

The stem bark of Terminalia arjuna Linn. (fam: Combretaceae), commonly known as Arjuna in Indian systems of medicine, is a reputed drug used for various cardiac\\u000a disorders. T. arjuna stem bark is reported to contain different groups of chemical constituents including phenolics, tannins, saponins and triterpenoid\\u000a acids. From our earlier experience with tannin containing herbal drugs, we are aware that

J. Kalola; M. Rajani

2006-01-01

90

Tannins, Peptic Ulcers and Related Mechanisms  

PubMed Central

This review of the current literature aims to study correlations between the chemical structure and gastric anti-ulcer activity of tannins. Tannins are used in medicine primarily because of their astringent properties. These properties are due to the fact that tannins react with the tissue proteins with which they come into contact. In gastric ulcers, this tannin-protein complex layer protects the stomach by promoting greater resistance to chemical and mechanical injury or irritation. Moreover, in several experimental models of gastric ulcer, tannins have been shown to present antioxidant activity, promote tissue repair, exhibit anti Helicobacter pylori effects, and they are involved in gastrointestinal tract anti-inflammatory processes. The presence of tannins explains the anti-ulcer effects of many natural products.

de Jesus, Neyres Zinia Taveira; de Souza Falcao, Heloina; Gomes, Isis Fernandes; de Almeida Leite, Thiago Jose; de Morais Lima, Gedson Rodrigues; Barbosa-Filho, Jose Maria; Tavares, Josean Fechine; da Silva, Marcelo Sobral; de Athayde-Filho, Petronio Filgueiras; Batista, Leonia Maria

2012-01-01

91

Semisynthetic digoxigenin glycosides  

Microsoft Academic Search

Starting with digoxigenin, L-rhamnose, D-glucose, and D-xylose, the monoglycosides digoxigenin-3-a-L-rhamnopyranoside, 3-ß-D-glycopyranoside, and 3-ß-D-xylopyranoside have been synthesized in approximately 40% yield. The biosides digoxigenin 3,12-di-ß-D-glucopyranoside and 3,12-di-ß-D-xylopyranoside were also obtained in approximately 3% yield. The glycosides obtained possessed high cardiotonic activity.

I. F. Makarevich

1969-01-01

92

Variants of glycoside hydrolases  

DOEpatents

The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

Teter, Sarah; Ward, Connie; Cherry, Joel; Jones, Aubrey; Harris, Paul; Yi, Jung

2013-02-26

93

Variants of glycoside hydrolases  

DOEpatents

The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

Teter, Sarah (Davis, CA); Ward, Connie (Hamilton, MT); Cherry, Joel (Davis, CA); Jones, Aubrey (Davis, CA); Harris, Paul (Carnation, WA); Yi, Jung (Sacramento, CA)

2011-04-26

94

Pregnane glycosides from Sansevieria trifasciata.  

PubMed

Phytochemical analysis of the whole plant of Sansevieria trifasciata, one of the most common Agavaceae plants, has resulted in the isolation of four new pregnane glycosides. Their structures have been determined by spectroscopic analysis and acid- and alkaline-catalysed hydrolysis to be 1 beta,3 beta-dihydroxypregna-5,16-dien-20-one glycosides. This is believed to be the first report of the isolation of the pregnane glycosides from a plant of the family Agavaceae. PMID:8983214

Mimaki, Y; Inoue, T; Kuroda, M; Sashida, Y

1997-01-01

95

Resin glycosides from Porana duclouxii.  

PubMed

A new intact resin glycoside (3) and two glycosidic acids (1 and 2), all having a common trisaccharide moiety and (11S)-hydroxytetradecanoic acid or (3S,11S)-dihydroxytetradecanoic acid as the aglycone, were obtained from the roots of Porana duclouxii. Their structures were elucidated by spectroscopic analyses and chemical correlations. These compounds represent the first examples of resin glycosides from the genus Porana. PMID:24320876

Ding, Wen-Bing; Zhang, Dai-Gui; Liu, Chun-Jie; Li, Guan-Hua; Li, You-Zhi

2014-01-01

96

Cytotoxic cardenolide glycosides from the root of Reevesia formosana.  

PubMed

Bioassay-guided fractionation of the root tissue of Reevesia formosana led to isolation of 13 cardenolide glycosides, reevesiosides A-I and epi-reevesiosides F-I. Their structures were determined by means of spectroscopic analysis and single-crystal X-ray diffraction was performed using reevesioside A. Reevesioside A, reevesioside F, and epi-reevesioside F displayed especially potent cytotoxicity against the MCF-7 and NCI-H460 cancer cell lines, with IC(50) values of 63±2 and 19±1, 72±8 and 20±0, and 34±6 and 10±1 nM, respectively. Identification of the sugar constituents and unusual 18,20-epoxide cardenolide glycosides are described herein. Cardiac glycosides were previously unknown in the Sterculiaceae family. PMID:23313131

Chang, Hsun-Shuo; Chiang, Michael Y; Hsu, Hsing-Yu; Yang, Cheng-Wei; Lin, Chu-Hung; Lee, Shiow-Ju; Chen, Ih-Sheng

2013-03-01

97

Quinoid glycosides from Forsythia suspensa.  

PubMed

Phytochemical investigation on Forsythia suspensa (Thunb.) Vahl afforded 10 compounds, including quinoid glycosides, lignan glycosides, phenylethanoid glycoside and allylbenzene glycoside together with 13 known ones. Their structures were established based on extensive spectroscopic data analyses, including IR, UV, HRESIMS, 1D NMR and 2D NMR. Absolute configurations were determined by ECD calculation method and chemical degradation. In addition, all compounds were evaluated for their antiviral activity against influenza A (H1N1) virus and several were further evaluated against respiratory syncytial virus (RSV) in vitro. Among them, two previously known compounds showed significant activities against RSV with EC50 values of 3.43 and 6.72 ?M. PMID:24833035

Li, Chang; Dai, Yi; Zhang, Shu-Xiang; Duan, Ying-Hui; Liu, Ming-Li; Chen, Liu-Yuan; Yao, Xin-Sheng

2014-08-01

98

Study on Vegetable Tannin in Nepal.  

National Technical Information Service (NTIS)

This report focuses on the growing demand for tannin in Nepal as a result of the establishment of various leather industries and the possible import substitution by indigenously produced vegetable tannin. It includes the list as well as relevant notes on ...

A. Kattel

1982-01-01

99

Colloidal stability of tannins: astringency, wine tasting and beyond  

NASA Astrophysics Data System (ADS)

Tannin-tannin and tannin-protein interactions in water-ethanol solvent mixtures are studied in the context of red wine tasting. While tannin self-aggregation is relevant for the visual aspect of wine tasting (limpidity and related colloidal phenomena), tannin affinities for salivary proline-rich proteins is fundamental for a wide spectrum of organoleptic properties related to astringency. Tannin-tannin interactions are analyzed in water-ethanol wine-like solvents and the precipitation map is constructed for a typical grape tannin. The interaction between tannins and human salivary proline-rich proteins (PRP) are investigated in the framework of the shell model for micellization, known for describing tannin-induced aggregation of ?-casein. Tannin-assisted micellization and compaction of proteins observed by SAXS are described quantitatively and discussed in the case of astringency.

Zanchi, D.; Poulain, C.; Konarev, P.; Tribet, C.; Svergun, D. I.

2008-12-01

100

Regeneration and cardiotonic glycoside production in Digitalis davisiana Heywood (Alanya Foxglove)  

Microsoft Academic Search

A high-frequency in vitro regeneration of Digitalis davisiana Heywood (Alanya foxglove) and cardiotonic glycoside production from both in vitro produced materials (regenerated plantlets\\u000a or germinated seedlings) and leaves of natural populations were obtained. Cardiac glycosides regulate heart rhythm and are\\u000a effective in cancer chemotherapy, in particular for prostate and breast cancer treatments. Testing six different types of\\u000a culture media revealed

Ekrem Gurel; Buhara Yucesan; Esra Aglic; Songul Gurel; Sandeep K. Verma; Munevver Sokmen; Atalay Sokmen

2011-01-01

101

Glycosyl fluorides in glycosidations.  

PubMed

This short review deals with the recent progress in chemical O-glycosidation and C-glycosylation methods using glycosyl fluorides as glycosyl donors. Pyranosyl and furanosyl fluorides were effectively activated by fluorophilic reagents such as SnCl2-AgClO4, SnCl2-TrClO4, SnCl2-AgOTf, TMSOTf, SiF4, BF3 x Et2O, TiF4, SnF4, Cp2MCl2-AgClO4 (M = Zr or Hf), Cp2ZrCl2-AgBF4, Cp2HfCl2-AgOTf, Bu2Sn(ClO4)2, Me2GaCl, Tf2O, LiClO4, Yb(OTf)3, La(ClO4)3 x nH2O, La(ClO4)3 x nH2O-Sn(OTf)2, Yb-Amberlyst 15, SO4/ZrO2, Nafion-H, montmorillonite K-10, and TrB(C6F5)4 to react with alcohols to give the corresponding O-glycosides in high yields. Furthermore, several types of C-glycosyl compounds, such as aryl, allyl and alkyl C-glycosyl derivatives, were also obtained by the glycosylation using glycosyl fluorides and the corresponding nucleophile with or without a Lewis acid. PMID:10968674

Toshima, K

2000-07-10

102

Lead chelation to immobilised Symphytum officinale L. (comfrey) root tannins  

Microsoft Academic Search

Reported correlations between tannin level and metal accumulation within plant tissues suggest that metal-chelating tannins may help plants to tolerate toxic levels of heavy metal contaminants. This paper supports such correlations using a new method that demonstrated the ability of plant tannins to chelate heavy metals, and showed that the relative levels of tannins in tissues were quantitatively related to

Lily Chin; David W. M. Leung; H. Harry Taylor

2009-01-01

103

Transgenic upregulation of the condensed tannin pathway in poplar leads to a dramatic shift in leaf palatability for two tree-feeding Lepidoptera.  

PubMed

Transgenic hybrid aspen (Populus tremula x tremuloides) overexpressing the MYB134 tannin regulatory gene show dramatically enhanced condensed tannin (proanthocyanidin) levels, as well as shifts in other phenolic metabolites. A series of insect bioassays with forest tent caterpillars (Malacosoma disstria) and gypsy moth (Lymantria dispar) caterpillars was carried out to determine how this metabolic shift affects food preference and performance of generalist tree-feeding lepidopterans. Both species showed a distinct preference for the high-tannin MYB134 overexpressor plants, and L. dispar performance was enhanced relative to controls. L. dispar reached greater pupal weight and showed reduced time to pupation when reared on the MYB134 overexpressing poplar. These results were unexpected since enhanced condensed tannin levels were predicted to act as feeding deterrents. However, the data may be explained by the observed decrease in the salicinoids (phenolic glycosides) salicortin and tremulacin that accompanied the upregulation of the condensed tannins in the transgenics. We conclude that for these two lepidopteran species, condensed tannin levels are unlikely to be a major determinant of caterpillar food preference or performance. However, our experiments show that overexpression of a single regulatory gene in transgenic aspen can have a significant impact on herbivorous insects. PMID:24496605

Boeckler, G Andreas; Towns, Megan; Unsicker, Sybille B; Mellway, Robin D; Yip, Lynn; Hilke, Ines; Gershenzon, Jonathan; Constabel, C Peter

2014-02-01

104

Naturally occurring methyl salicylate glycosides.  

PubMed

As an important part of non steroids anti-inflammation drug (NSAIDs), salicylate has developed from natural substance salicylic acid to natrium salicylicum, to aspirin. Now, methyl salicylate glycoside, a new derivative of salicylic acid, is modified with a -COOH group integrated one methyl radical into formic ether, and a -OH linked with a monosaccharide, a disaccharide or a trisaccharide unit by glycosidic linkage. It has the similar pharmacological activities, anti-inflammatory, analgesic, antipyretic and antithrombotic as the previous salicylates' without resulting in serious side effects, particularly the gastrointestinal toxicity. Owing to the superiority of those significant bioactivities, methyl salicylate glycosides have became a hot research area in NSAIDs for several years. This paper compiles all 9 naturally occurring methyl salicylate glycosides, their distribution of the resource and pharmacological mechanism, which could contribute to the new drug discovery. PMID:24329991

Mao, Ping; Liu, Zizhen; Xie, Meng; Jiang, Rui; Liu, Weirui; Wang, Xiaohong; Meng, Shen; She, Gaimei

2014-01-01

105

Phenylpropanoid glycosides from Smilax glabra  

Microsoft Academic Search

Five phenylpropanoid esters of sucrose glycosides, trivially named smiglasides A–E, were isolated from the rhizomes of Smilax glabra. Their structures were elucidated on the basis of spectroscopic studies.

Ting Chen; Jian-Xin Li; Qiang Xu

2000-01-01

106

Condensed tannins act against cattle nematodes.  

PubMed

The use of natural plant anthelmintics was suggested as a possible alternative control of gastrointestinal nematodes (GIN) in ruminants. Direct anthelmintic effects of tannin-containing plants have already been shown in sheep and goat GIN. These anthelmintic properties are mainly associated with condensed tannins. In the present study, we evaluated possible in vitro effects of three tannin-containing plants against bovine GIN. Effects of Onobrychis viciifolia, Lotus pedunculatus and Lotus corniculatus condensed tannin (CT) extracts on Cooperia oncophora and Ostertagia ostertagi were determined by a larval feeding inhibition assay (LFIA) and a larval exsheathment assay (LEA). In the LFIA, all three plant extracts significantly inhibited larval feeding behaviour of both C. oncophora and O. ostertagi first stage larvae in a dose-dependent manner. The L. pedunculatus extract, based on EC(50) (effective concentration for 50% inhibition), was the most effective against both nematodes, followed by O. viciifolia and L. corniculatus. The effect of CT extracts upon larval feeding behaviour correlates with CT content and procyanidin/prodelphidin ratio. Larval exsheathment of C. oncophora and O. ostertagi L3 larvae (third stage larvae) was also affected by CT extracts from all three plants. In both in vitro assays, extracts with added polyvinylpolypyrrolidone, an inhibitor of tannins, generated almost the same values as the negative control; this confirms the role of CT in the anthelmintic effect of these plant extracts. Our results, therefore, indicated that tannin-containing plants could act against cattle nematodes. PMID:21726942

Novobilský, Adam; Mueller-Harvey, Irene; Thamsborg, Stig Milan

2011-12-15

107

Interaction of gut microflora with tannins in feeds  

NASA Astrophysics Data System (ADS)

Tannins (hydrolyzable and condensed) are water-soluble polyphenolic compounds that exert antinutritional effects on ruminants by forming complexes with dietary proteins. They limit nitrogen supply to animals, besides inhibiting the growth and activity of ruminal microflora. However, some gastrointestinal microbes are able to break tannin-protein complexes while preferentially degrading hydrolyzable tannins (HTs). Streptococcus gallolyticus, Lonepinella koalarum and Selenomonas ruminantium are the dominant bacterial species that have the ability to degrade HTs. These tanninolytic microorganisms possess tannin-degrading ability and have developed certain mechanisms to tolerate tannins in feeds. Hence, selection of efficient tanninolytic microbes and transinoculation among animals for long-term benefits become areas of intensive interest. Here, we review the effects of tannins on ruminants, the existence and significance of tannin-degrading microorganisms in diverse groups of animals and the mechanisms that tannin-degrading microorganisms have developed to counter the toxic effects of tannin.

Goel, Gunjan; Puniya, A. K.; Aguilar, C. N.; Singh, Kishan

2005-11-01

108

On the differences between ouabain and digitalis glycosides.  

PubMed

Digoxin and digitoxin are widely used in the treatment of heart diseases. The exact mechanism of action of these drugs has remained an enigma. Ouabain has become the standard tool to investigate the mode of action of cardiotonic steroids, and results with ouabain are regarded as generally valid for all cardiac glycosides. However, there are marked differences between the effects of ouabain and digitalis glycosides. Ouabain has a different therapeutic profile from digitalis derivatives. Unlike digitalis glycosides, ouabain has a fast onset of action and stimulates myocardial metabolism. The inotropic effect of cardiotonic steroids is not related to inhibition of the Na-K-ATPase. Ouabain and digitalis derivatives develop their effects in different cellular spaces. Digitalis glycosides increase the intracellular calcium concentration by entering the cell interior and acting on the ryanodine receptors and by forming transmembrane calcium channels. Ouabain, by activation of the Na-K-ATPase from the extracellular side, triggers release of calcium from intracellular stores via signal transduction pathways and activates myocardial metabolism. These data no longer support the concept that all cardiotonic steroids exhibit their therapeutic effects by partial inhibition of the ion-pumping function of the Na-K-ATPase. Hence, it is suggested that this deeply rooted dogma be revised. PMID:21642827

Fuerstenwerth, Hauke

2014-01-01

109

A method to determine tannin concentration by the measurement and quantification of protein — tannin interactions  

Microsoft Academic Search

Protein determinations on protein-tannin complexes after protein isolation (gel filtration and trichloroacetic acid [TCA] precipitation) or phenolic extraction (polyvinyl pyrrolidone [PVP] and organic solvent precipitation) were unsuccessuful. Kjeldahl determinations of the amount of unprecipitated protein bovine serum albumin [BSA] showed a sigmoid relationship with increasing concentrations of tannins. A similar relationship was found for the reduced viscosity of BSA and

A. M. Amory; C. L. Schubert

1987-01-01

110

Multifunctional porous solids derived from tannins  

NASA Astrophysics Data System (ADS)

Tannins are extremely valuable, non toxic, wood extractives combining reactivity towards aldehydes, low cost, natural origin and easy handling. When polymerized in the presence of suitable chemicals including blowing agent, ultra lightweight rigid tannin-based foams are obtained. If pyrolyzed under inert gas, reticulated carbon foams having the same pore structure and the same density are obtained. The most remarkable features of tannin-based foams are the following: mechanical resistance similar to, or higher than, that of commercial phenolic foams, tuneable pore size and permeability, infusibility, very low thermal conductivity, cheapness, ecological character, high resistance to flame and to chemicals. Carbon foams have even better properties and are also electrically conducting. Consequently, various applications are suggested for organic foams: cores of sandwich composite panels, sound and shock absorbers and thermal insulators, whereas carbon foams can be used as porous electrodes, filters for molten metals and corrosive chemicals, catalyst supports and adsorbents.

Celzard, Alain; Fierro, Vanessa; Pizzi, Antonio; Zhao, Weigang

2013-03-01

111

Tannin Composition Affects the Oxidative Activities of Tree Leaves  

Microsoft Academic Search

We examined whether tannin composition plays an important role in explaining the oxidative activities of tree leaves of Acer saccharum (sugar maple) and Quercus rubra (red oak). Sugar maple leaves contained substantial amounts of ellagitannins, condensed tannins, and galloyl glucoses, whereas red oak leaves contained almost exclusively condensed tannins. Oxidative activities of the crude phenolics from both species, and the

Raymond V. Barbehenn; Christopher P. Jones; Maarit Karonen; Juha-Pekka Salminen

2006-01-01

112

Flavanone glycosides from Alhagi pseudalhagi  

Microsoft Academic Search

Two new flavanone glycosides, alhagitin and alhagidin, have been isolated from the whole plant of Alhagi pseudalhagi and their structures established respectively as naringenin 5-methyl ether 4?-glucoside and hesperitin 7-galactosyl(1?2)[rhamnosyl(1?6)]glucoside by chemical and spectroscopic methods.

V. P Singh; Bineeta Yadav; V. B Pandey

1999-01-01

113

Flavanone glycosides from Alhagi pseudalhagi.  

PubMed

Two new flavanone glycosides, alhagitin and alhagidin, have been isolated from the whole plant of Alhagi pseudalhagi and their structures established respectively as naringenin 5-methyl ether 4'-glucoside and hesperitin 7-galactosyl(1-->2)[rhamnosyl(1-->6)]glucoside by chemical and spectroscopic methods. PMID:10389270

Singh, V P; Yadav, B; Pandey, V B

1999-06-01

114

Biosynthesis of tannin acyl hydrolase from tannin-rich forest residue under different fermentation conditions  

Microsoft Academic Search

  Caesalpinia digyna, a tannin-rich forest residue, was used as substrate for production of tannase and gallic acid. Media engineering\\u000a was carried out under solid-state fermentation, submerged fermentation and modified solid state fermentation conditions for\\u000a optimum synthesis of tannase and gallic acid (based on 58% tannin content in the raw material). Tannase vis-à-vis gallic acid\\u000a recovery under modified solid-state fermentation condition

B Kar; R Banerjee

2000-01-01

115

Science Study Aids 5: Tannin - Nature's Filter.  

ERIC Educational Resources Information Center

This publication is the fifth in a series of seven supplementary investigative materials for use in secondary science classes providing up-to-date research-related investigations. This unit is structured for grade levels 9 through 12. It is concerned with the removal of heavy divalent metals from water with the use of tannin-containing…

Boeschen, John; Randall, John M.

116

Tolerance of acridids to ingested condensed tannin  

Microsoft Academic Search

Four species of Acridoidea were fed on wheat leaves with and without the condensed tannin, quebracho. In no case was it deleterious to survival and growth at levels below about 10% dry weight on the food. Similarly, consumption, digestibility, and utilization of food were unaffected at up to 10% dry weight. At higher concentrations, however, the consumption and the efficiency

E. A. Bernays; D. J. Chamberlain; E. M. Leather

1981-01-01

117

Extraction of tannin from fresh and preserved leaves.  

PubMed

The extractability of tannin from fresh, lyophilized, and dried leaves collected at various times in the growing season was determined using the radial diffusion assay for protein-precipitating phenolics. The amount of tannin extracted depended on the method of leaf preservation and on the maturity of the leaf. Early in the season, more tannin was extracted from lyophilized leaves than from fresh leaves, but late in the season more tannin was extracted from fresh leaves. At all times, more tannin was extracted with aqueous acetone than with aqueous or acidic methanol. PMID:24275992

Hagerman, A E

1988-02-01

118

Lead chelation to immobilised Symphytum officinale L. (comfrey) root tannins.  

PubMed

Reported correlations between tannin level and metal accumulation within plant tissues suggest that metal-chelating tannins may help plants to tolerate toxic levels of heavy metal contaminants. This paper supports such correlations using a new method that demonstrated the ability of plant tannins to chelate heavy metals, and showed that the relative levels of tannins in tissues were quantitatively related to lead chelation in vitro. Using this in vitro metal chelation method, we showed that immobilised tannins prepared from lateral roots of Symphytum officinale L., that contained high tannin levels, chelated 3.5 times more lead than those from main roots with lower tannin levels. This trend was confirmed using increasing concentrations of tannins from a single root type, and using purified tannins (tannic acid) from Chinese gallnuts. This study presents a new, simple, and reliable method that demonstrates direct lead-tannin chelation. In relation to phytoremediation, it also suggests that plant roots with more 'built-in' tannins may advantageously accumulate more lead. PMID:19477483

Chin, Lily; Leung, David W M; Harry Taylor, H

2009-07-01

119

Tannin-assisted aggregation of natively unfolded proteins  

NASA Astrophysics Data System (ADS)

Tannin-protein interactions are essentially physical: hydrophobic and hydrogen-bond-mediated. We explored the tannin-assisted protein aggregation on the case of ?-casein, which is a natively unfolded protein known for its ability to form micellar aggregates. We used several tannins with specified length. Our SAXS results show that small tannins increase the number of proteins per micelle, but keeping their size constant. It leads to a tannin-assisted compactization of micelles. Larger tannins, with linear dimensions greater than the crown width of micelles, lead to the aggregation of micelles by a bridging effect. Experimental results can be understood within a model where tannins are treated as effective enhancers of hydrophobic attraction between specific sites in proteins.

Zanchi, D.; Narayanan, T.; Hagenmuller, D.; Baron, A.; Guyot, S.; Cabane, B.; Bouhallab, S.

2008-06-01

120

Tannin composition affects the oxidative activities of tree leaves.  

PubMed

We examined whether tannin composition plays an important role in explaining the oxidative activities of tree leaves of Acer saccharum (sugar maple) and Quercus rubra (red oak). Sugar maple leaves contained substantial amounts of ellagitannins, condensed tannins, and galloyl glucoses, whereas red oak leaves contained almost exclusively condensed tannins. Oxidative activities of the crude phenolics from both species, and the phenolic fractions from sugar maple, were measured with electron paramagnetic resonance (EPR) spectrometry and UV-visible spectrophotometry. The two assays produced similar results: (1) sugar maple phenolics produced larger semiquinone radical concentrations,and higher semiquinone decay rates and browning rates than did red oak phenolics; (2) ellagitannin levels were positively associated with the three measures of oxidative activity; and (3) condensed tannin and galloyl glucose levels were negatively associated with these measures. The negative relationship between condensed tannin levels and oxidative activity resulted from the antioxidant effects of condensed tannins on hydrolyzable tannins; several purified condensed tannins significantly decreased the concentrations of semiquinone radicals and browning rates of pedunculagin (an ellagitannin) and pentagalloyl glucose. As expected, whole-leaf extracts from sugar maple produced elevated levels of semiquinone radicals, but none were observed in red oak extracts when the two species were compared with an EPR time-course assay. We conclude that the oxidative activities of tree leaves may be affected by tannin composition, and that the prooxidant activity of ellagitannins may be decreased by co-occurring condensed tannins. PMID:17031601

Barbehenn, Raymond V; Jones, Christopher P; Karonen, Maarit; Salminen, Juha-Pekka

2006-10-01

121

Myricetin glycosides from Licania densiflora.  

PubMed

Dried leaves of Licania densiflora yielded five myricetin glycosides: myricetin 3'-methylether-3-O-glucoside (1), myricetin 3'-methylether-3-O-galactoside (2), myricetin 4'-methylether-3-O-rhamnoside (3), myricetin 3',5'-dimethylether-3-O-glucoside (4), and myricetin 3',5'-dimethylether-3-O-rhamnoside (5). Their structures were elucidated by spectroscopic methods including mono- and bi-dimensional NMR techniques. PMID:11223232

Braca, A; Bilia, A R; Mendez, J; Morelli, I

2001-02-01

122

Interaction of tannin with human salivary proline-rich proteins.  

PubMed

Tannins are polyphenolic compounds, widely distributed in plant-based foods, which have harmful effects on animals including humans. Salivary proline-rich proteins (PRPs) may act as a defence against tannins by forming complexes with them and thereby preventing their interaction with other biological compounds and absorption from the intestinal canal. The aim here was to compare the ability of members of the family of human PRPs to form insoluble complexes with tannin and to assess the stability of such complexes under conditions similar to those in the alimentary tract. Basic PRPs (BPRPs), which have no other known biological functions, were very effective in forming insoluble complexes with both condensed tannin and tannic acid. Practically no tannin bound to acidic PRPs (APRPs) and glycosylated PRPs (GPRPs), suggesting that tannin in the diet would not affect their biological activities. There were only small differences in the tannin-precipitating ability of various BPRPs of different sizes or sequences, indicating that, although there is considerable phenotypic variation of PRPs, it is not likely to cause marked individual variation in tannin-binding ability. Tryptic digestion of an APRP led to a marked increase in tannin binding to the resulting proline-rich peptides, supporting observations in other studies that there may be an interaction between the proline-poor N-terminal and the proline-rich C-terminal regions in native APRPs, which inhibits the biological activities of the proteins. Deglycosylation of a GPRP also led to a dramatic increase in tannin-binding ability, showing that the carbohydrate side-chains prevent binding of tannin. Most of the condensed tannin-PRP complexes remained insoluble under conditions similar to those in the stomach and small intestine, supporting the proposal that PRPs act as a defence against tannin. PMID:9783826

Lu, Y; Bennick, A

1998-09-01

123

Effects and fate of tannins in ruminant animals, adaptation to tannins, and strategies to overcome detrimental effects of feeding tannin-rich feeds  

Microsoft Academic Search

Trees and shrub foliage and agro-industrial by-products are of importance in animal production because they do not compete with human food and can provide significant protein supplements, especially in the dry season. But, these feed resources are generally rich in antinutritional factors, particularly tannins. The amount of tannins that they contain vary widely and largely unpredictably, and their effects on

H. P. S. Makkar

2003-01-01

124

Cytotoxic phenylethanol glycosides from Psidium guaijava seeds  

Microsoft Academic Search

Phytochemical investigations of the acetone extract of Psidium guaijava seeds has led to the isolation of five known flavonoid glycosides, two phenolic glycosides and two new phenylethanoid glycosides which have been identified as 1-O-3,4-dimethoxy-phenylethyl-4-O-3,4-dimethoxy cinnamoyl-6-O-cinnamoyl-?-d-glucopyranose and 1-O-3,4-dimethoxyphenylethyl-4-O-3,4-dimethoxy cinnamoyl-?-d-glucopyranose, on the basis of chemical, physical and spectroscopic methods of analysis.

Josline Y. Salib; Helana N. Michael

2004-01-01

125

[The antifungal action of polygalacic acid glycosides].  

PubMed

Triterpenoid glycosides obtained from Solidago virgaurea L. and Bellis perennis L. (Asteraceae) inhibit the growth of human-pathogenic yeasts (Candida and Cryptococcus species). First results are given of the investigations on the mode of action and the relationships between structure and activity of these compounds. The intensity of growth inhibition is influenced particularly by the carbohydrate chains of the glycosides. Monodesmosidic as well as bisdesmosidic glycosides of polygalacic acid exert fungicidic effects. PMID:2080212

Bader, G; Kulhanek, Y; Ziegler-Böhme, H

1990-07-01

126

Douglas-Fir Bark Tannin Decomposition in Two Forest Soils.  

National Technical Information Service (NTIS)

Purified Douglas-fir bark tannin equivalent to the amount in a 2-inch bark mulch was added to two widely different soils in the laboratory. About 22 percent of the tannin decomposed in 180 days. Soil microflora generally increased. Nitrate production was ...

W. B. Bollen K. C. Lu

1969-01-01

127

Microbial interactions with tannins: nutritional consequences for ruminants  

Microsoft Academic Search

Polyphenolics are widely distributed in the plant kingdom and are often present in the diet of herbivores. The two major groups of plant polyphenolic compounds other than lignin are condensed and hydrolysable tannins. These compounds can have toxic and\\/or antinutritional effects on the animal. It is well established that tannins complex with dietary proteins can reduce nitrogen supply to the

C. S McSweeney; B Palmer; D. M McNeill; D. O Krause

2001-01-01

128

Absorption of mercuric cation by tannins in agricultural residues  

Microsoft Academic Search

Two common environmental pollutants are agricultural residues (skins, pits, husks, tannin bark, grape pomace) and waste streams of water containing only traces of heavy metals (such as mercury at 10 or more ppb) from mining or manufacturing operations. Agricultural residues contain tannins, polyphenolic substances, pectin, and other polymers-all with chemically reactive groups that can chelate, reduce, oxidize, demonstrate ion exchange

A. C. Jr. Waiss; M. E. Wiley; J. A. Kuhnle; A. L. Potter; R. M. McCready

1973-01-01

129

High Density Biocomposite from Natural Fibers and Tannin Resin  

Microsoft Academic Search

Successful experiments on high, medium and low density natural fiber reinforced composites made from tannin\\/hexamine resin and flax–hemp fibers have recently been carried out. This study focused on the high density composites. In this work composite panels have been made of three different tannin extracts: mimosa, sulfited mimosa and quebracho, each with their own properties. The panels were tested for

A. Nicollin; R. Kueny; L. Toniazzo; A. Pizzi

2012-01-01

130

Steroidal glycosides with antiproliferative activities from Digitalis trojana.  

PubMed

The phytochemical investigation of Digitalis trojana led to the isolation of two cardiac glycosides (1, 2), one pregnane glycoside (3), three furostanol type saponins (4-6), along with three cleroindicins (7-9), four phenylethanoid glycosides (10-13), two flavonoids (14, 15) and two phenolic acid derivatives (16, 17). The structure elucidation of the isolates was carried out by NMR experiments as well as ESI-MS. The cytotoxic activity of compounds 1-13 against a small panel of cancer cell lines, namely MCF-7, T98G, HT-29, PC-3, A375 and SH-SY5Y, was investigated. Compounds 1-6 showed antiproliferative activity against human breast MCF-7 and colon HT-29 cancer cell lines with IC50 values ranging from 8.3 to 50??M. In order to understand the mechanism involved in the cell death, the active compounds were tested as pro-apoptotic agents using propidium iodide staining by flow cytometry method. No significant increase was observed in the apoptosis of the MCF-7 and HT-29 cancer cells. Moreover, the effects of the active compounds on cell proliferation were assessed on the same cancer cell lines by cell cycle analysis of DNA content using flow cytometry. No significative changes were observed in the cell cycle of MCF-7, while significant changes in G2 /M cell cycle phase of HT-29 cells were observed after treatment with digitalin (1), cariensoside (3) and 22-O-methylparvispinoside B (6) at 10??M. PMID:23722601

Kirmizibekmez, Hasan; Masullo, Milena; Festa, Michela; Capasso, Anna; Piacente, Sonia

2014-04-01

131

New kaurene diterpenoid glycosides from fenugreek seeds.  

PubMed

Two new kaurene diterpenoid glycosides, named Graecumoside A (1) and B (2), were isolated from fenugreek seeds, along with three known flavonoid-C-glycosides, isoorientin (3), isovitexin (4) and vitexin (5). By combined analyses of 1D- and 2D-NMR, and MS spectroscopy, the structures of two new compounds were elucidated as 3-O-?- D-glucopyranosyl kaur-5, 16-dien-3?, 6, 13?-trihydroxy-7-oxo-18-oic acid methyl ester and 3-O-?-neohesperidosyl kaur-5, 16-dien-3?, 6, 13?-trihydroxy-7-oxo-18-oic acid methyl ester, respectively. The kaurene diterpenoid glycosides were first isolated and identified from fenugreek seeds. PMID:22950814

Pang, Xu; Kang, Li-Ping; Yu, He-Shui; Zhao, Yang; Xiong, Cheng-Qi; Zhang, Jie; Ma, Bai-Ping

2013-01-01

132

A new furostanol glycoside from Tribulus terrestris.  

PubMed

Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furostane-20(22)-en-12-one-3beta, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside (1) on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations. PMID:20335931

Xu, Yajuan; Liu, Yonghong; Xu, Tunhai; Xie, Shengxu; Si, Yunshan; Liu, Yue; Zhou, Haiou; Liu, Tonghua; Xu, Dongming

2010-02-01

133

Glycerol Glycoside Esters of Fatty Acids.  

National Technical Information Service (NTIS)

The patent application relates to compositions of matter containing esters of glycosides and 6 to 24 carbon atom fatty acids, which compositions are useful as surface-active agents. More particularly, this invention relates to compositions of matter obtai...

R. O. Feuge J. L. White M. L. Brown

1974-01-01

134

Four new cycloartane glycosides from Aquilegia vulgaris.  

PubMed

Four new cycloartane glycosides, named aquilegiosides G-J, were isolated from the dried aerial parts of Aquilegia vulgaris. Their structures were determined by spectroscopic analysis and chemical evidence. PMID:12913235

Nishida, Makiko; Yoshimitsu, Hitoshi; Okawa, Masafumi; Nohara, Toshihiro

2003-08-01

135

Tannin signatures of barks, needles, leaves, cones, and wood at the molecular level  

NASA Astrophysics Data System (ADS)

We analyzed 117 tissues from 77 different plant species for molecular tannin. Tannin was measured in 89 tissues (as high as 10.5 wt.% total tannin), including procyanidin (PC) tannin in 88 tissues, prodelphinidin (PD) tannin in 50, and propelargonidin (PP) tannin in 24. In addition to tannin, several flavones, flavanones, and triterpenoids were measured, the latter which yielded as much as 4.5 wt.%. Compositions varied considerably between species, including several that yielded comparatively rare tannin or triterpenoids. Conifer needles were distinguished by high yields of PD tannin overall and relative to PC tannin. Dicotyledon leaves were characterized by the presence of flavones and triterpenoids. Barks were marked by flavanones and tetracosanoic acid. Based on these trends, relationships that could be useful as geochemical parameters were developed for distinguishing needles, leaves, and barks as possible components of litter, soil, or sedimentary mixtures.

Hernes, Peter J.; Hedges, John I.

2004-03-01

136

Tannins from Canarium album with potent antioxidant activity*  

PubMed Central

The contents of total phenolics and extractable condensed tannins in the leaves, twigs and stem bark of Canarium album were determined. The structural heterogeneity of condensed tannins from stem bark was characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) analyses. The results show the predominance of signals representative of procyanidins and prodelphinidins. In addition, epicatechin and epigallocatechin polymers with galloylated procyanidin or prodelphinidin were also observed. The tannins were screened for their potential antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) model systems. Tannins extracted from leaves, twigs and stem bark all showed a very good DPPH radical scavenging activity and ferric reducing power.

Zhang, Liang-liang; Lin, Yi-ming

2008-01-01

137

Biological Treatment of Spent Vegetable Tannins with Fungal Dominant System.  

National Technical Information Service (NTIS)

Feasibility of aerobic biological treatment of spent vegetable tannins with primarily fungal culture was investigated. Growth rate of cells, yield coefficients, oxygen uptake rate, specific substrate utilization rates, sludge settleability, and process pe...

M. D. Atluru

1972-01-01

138

Structural features and antioxidant activity of tannin from persimmon pulp  

Microsoft Academic Search

Phenolic compounds from persimmon pulp were extracted with methanol acidified with 1% HCl, and then purified on AB-8 macroporous resin. The tannic extracts obtained were fractionated by polysulfone ultrafiltration membrane with molecular weight cutoff of 10,000Da into two fractions: low molecular weight tannin (LMWT) and high molecular weight tannin (HMWT). HPLC–MS analysis showed that gallic acid was one of the

Hai-Feng Gu; Chun-Mei Li; Yu-juan Xu; Wan-feng Hu; Mei-hong Chen; Qiong-hong Wan

2008-01-01

139

Effect of tannins on the in vitro growth of Clostridium perfringens.  

PubMed

Vegetable tannins are water-soluble polyphenolic compounds of varying molecular weights that occur abundantly in nature. The diet of many free-ranging wild animals contains significant amounts of tannins. Also, commercial tannins are used in animal industry as food additives to improve animal performance. In order to further determine the capacity of tannins to inhibit the development of intestinal diseases produced by Clostridium pefringens, we evaluated here the effect of tannins from quebracho, chestnut or combinations of both on C. perfringens and their toxins. The C. perfringens (types A, B, C, D and E) growth obtained from the intestine of healthy and diseased animals was reduced in a dose-dependent manner in the presence of quebracho tannins, chestnut tannins, combinations of both or a commercial formula based in these tannins. Although the minimal inhibitory concentration of both tannins varied between isolates, no statistically significant differences were observed between isolates from healthy or sick animals. Comparative analysis showed that the concentrations of quebracho tannin inhibiting the growth of C. perfringens were higher than chestnut tannin. In fact, antibacterial effect of quebracho tannin was increased up to 20 times with the addition of 25% of chestnut tannin and 85 times with 75% of chestnut tannin. Antibacterial activity of the commercial product was up to ~50 times higher than quebracho tannin alone. Quebracho tannin showed partial bactericidal activity, whereas chestnut tannin activity was stronger. Both tannins were able to reduce the alpha toxin lecithinase activity and epsilon toxin cytotoxicity in MDCK cells. These results suggest that tannin-supplemented diet could be useful to prevent some clostridial diseases. PMID:20471759

Elizondo, Ana M; Mercado, Elsa C; Rabinovitz, Bettina C; Fernandez-Miyakawa, Mariano E

2010-10-26

140

Presence of tannins in sorghum grains is conditioned by different natural alleles of Tannin1  

PubMed Central

Sorghum, an ancient old-world cereal grass, is the dietary staple of over 500 million people in more than 30 countries in the tropics and semitropics. Its C4 photosynthesis, drought resistance, wide adaptation, and high nutritional value hold the promise to alleviate hunger in Africa. Not present in other major cereals, such as rice, wheat, and maize, condensed tannins (proanthocyanidins) in the pigmented testa of some sorghum cultivars have been implicated in reducing protein digestibility but recently have been shown to promote human health because of their high antioxidant capacity and ability to fight obesity through reduced digestion. Combining quantitative trait locus mapping, meta-quantitative trait locus fine-mapping, and association mapping, we showed that the nucleotide polymorphisms in the Tan1 gene, coding a WD40 protein, control the tannin biosynthesis in sorghum. A 1-bp G deletion in the coding region, causing a frame shift and a premature stop codon, led to a nonfunctional allele, tan1-a. Likewise, a different 10-bp insertion resulted in a second nonfunctional allele, tan1-b. Transforming the sorghum Tan1 ORF into a nontannin Arabidopsis mutant restored the tannin phenotype. In addition, reduction in nucleotide diversity from wild sorghum accessions to landraces and cultivars was found at the region that codes the highly conserved WD40 repeat domains and the C-terminal region of the protein. Genetic research in crops, coupled with nutritional and medical research, could open the possibility of producing different levels and combinations of phenolic compounds to promote human health.

Wu, Yuye; Li, Xianran; Xiang, Wenwen; Zhu, Chengsong; Lin, Zhongwei; Wu, Yun; Li, Jiarui; Pandravada, Satchidanand; Ridder, Dustan D.; Bai, Guihua; Wang, Ming L.; Trick, Harold N.; Bean, Scott R.; Tuinstra, Mitchell R.; Tesso, Tesfaye T.; Yu, Jianming

2012-01-01

141

Phytosterol glycosides reduce cholesterol absorption in humans  

PubMed Central

Dietary phytosterols inhibit intestinal cholesterol absorption and regulate whole body cholesterol excretion and balance. However, they are biochemically heterogeneous and a portion is glycosylated in some foods with unknown effects on biological activity. We tested the hypothesis that phytosterol glycosides reduce cholesterol absorption in humans. Phytosterol glycosides were extracted and purified from soy lecithin in a novel two-step process. Cholesterol absorption was measured in a series of three single-meal tests given at intervals of 2 wk to each of 11 healthy subjects. In a randomized crossover design, participants received ?300 mg of added phytosterols in the form of phytosterol glycosides or phytosterol esters, or placebo in a test breakfast also containing 30 mg cholesterol-d7. Cholesterol absorption was estimated by mass spectrometry of plasma cholesterol-d7 enrichment 4–5 days after each test. Compared with the placebo test, phytosterol glycosides reduced cholesterol absorption by 37.6 ± 4.8% (P < 0.0001) and phytosterol esters 30.6 ± 3.9% (P = 0.0001). These results suggest that natural phytosterol glycosides purified from lecithin are bioactive in humans and should be included in methods of phytosterol analysis and tables of food phytosterol content.

Lin, Xiaobo; Ma, Lina; Racette, Susan B.; Anderson Spearie, Catherine L.; Ostlund, Richard E.

2009-01-01

142

Diterpene glycosides from Stevia phlebophylla A. Gray.  

PubMed

The rare Mexican species Stevia phlebophylla A. Gray was long considered to be the only known Stevia species, beside the well-known S. rebaudiana, containing the highly sweet diterpenoid steviol glycosides. We report a re-evaluation of this claim after phytochemically screening leaves obtained from two herbarium specimens of S. phlebophylla for the presence of steviol glycosides. Despite extensive MS analyses, no steviol glycosides could be unambiguously verified. Instead, the main chromatographic peak eluting at retention times similar to those of steviol glycosides was identified as a new compound, namely 16?-hydroxy-17-acetoxy-ent-kauran-19-oic acid-(6-O-?-D-xylopyranosyl-?-D-glucopyranosyl) ester (1) on the basis of extensive NMR and MS data as well as the characterization of its acid hydrolysate. Seven more compounds were detected by ESIMS which are possibly structurally related to 1. It can therefore be concluded that S. phlebophylla is unlikely to contain significant amounts of steviol glycosides, if any. PMID:23831634

Ceunen, Stijn; Wim, De Borggraeve; Compernolle, Frans; Mai, Anh Hung; Geuns, Jan M C

2013-09-20

143

Tree resistance to Lymantria dispar caterpillars: importance and limitations of foliar tannin composition.  

PubMed

The ability of foliar tannins to increase plant resistance to herbivores is potentially determined by the composition of the tannins; hydrolyzable tannins are much more active as prooxidants in the guts of caterpillars than are condensed tannins. By manipulating the tannin compositions of two contrasting tree species, this work examined: (1) whether increased levels of hydrolyzable tannins increase the resistance of red oak (Quercus rubra L.), a tree with low resistance that produces mainly condensed tannins, and (2) whether increased levels of condensed tannins decrease the resistance of sugar maple (Acer saccharum Marsh.), a tree with relatively high resistance that produces high levels of hydrolyzable tannins. As expected, when Lymantria dispar L. caterpillars ingested oak leaves coated with hydrolyzable tannins, levels of hydrolyzable tannin oxidation increased in their midgut contents. However, increased tannin oxidation had no significant impact on oxidative stress in the surrounding midgut tissues. Although growth efficiencies were decreased by hydrolyzable tannins, growth rates remained unchanged, suggesting that additional hydrolyzable tannins are not sufficient to increase the resistance of oak. In larvae on condensed tannin-coated maple, no antioxidant effects were observed in the midgut, and levels of tannin oxidation remained high. Consequently, neither oxidative stress in midgut tissues nor larval performance were significantly affected by high levels of condensed tannins. Post hoc comparisons of physiological mechanisms related to tree resistance revealed that maple produced not only higher levels of oxidative stress in the midgut lumen and midgut tissues of L. dispar, but also decreased protein utilization efficiency compared with oak. Our results suggest that high levels of hydrolyzable tannins are important for producing oxidative stress, but increased tree resistance to caterpillars may require additional factors, such as those that produce nutritional stress. PMID:19148684

Barbehenn, Raymond V; Jaros, Adam; Lee, Grace; Mozola, Cara; Weir, Quentin; Salminen, Juha-Pekka

2009-04-01

144

Steviol glycosides: chemical diversity, metabolism, and function.  

PubMed

Steviol glycosides are a group of highly sweet diterpene glycosides discovered in only a few plant species, most notably the Paraguayan shrub Stevia rebaudiana. During the past few decades, the nutritional and pharmacological benefits of these secondary metabolites have become increasingly apparent. While these properties are now widely recognized, many aspects related to their in vivo biochemistry and metabolism and their relationship to the overall plant physiology of S. rebaudiana are not yet understood. Furthermore, the large size of the steviol glycoside pool commonly found within S. rebaudiana leaves implies a significant metabolic investment and poses questions regarding the benefits S. rebaudiana might gain from their accumulation. The current review intends to thoroughly discuss the available knowledge on these issues. PMID:23713723

Ceunen, Stijn; Geuns, Jan M C

2013-06-28

145

Acylated flavonoid glycosides from Bassia muricata  

Microsoft Academic Search

From the arial parts of Bassia muricata, two acylated flavonoid glycosides quercetin-3-O-(6?-caffeoyl)-sophoroside and quercetin-3-O-(6?-feruloyl)-sophoroside have been isolated together with two known flavonoid glycosides quercetin-3-O-sophoroside and quercetin-3,7-O-?-diglucopyranoside, as well as four known triterpenoidal saponins, oleanolic acid-3-O-?-glucopyranoside, chikusetsusaponin IVa, chikusetsusaponin IVa methyl ester and oleanolic acid-3,28-?-diglucopyranoside. The structures of the isolated compounds were verified by means of MS and NMR spectral analyses.

Mohamed S. Kamel; Khaled M. Mohamed; Hashim A. Hassanean; Kazuhiro Ohtani; Ryoji Kasai; Kazuo Yamasaki

2001-01-01

146

Acylated flavonoid glycosides from Bassia muricata.  

PubMed

From the arial parts of Bassia muricata, two acylated flavonoid glycosides quercetin-3-O-(6"-caffeoyl)-sophoroside and quercetin-3-O-(6"-feruloyl)-sophoroside have been isolated together with two known flavonoid glycosides quercetin-3-O-sophoroside and quercetin-3,7-O-beta-diglucopyranoside, as well as four known triterpenoidal saponins, oleanolic acid-3-O-beta-glucopyranoside, chikusetsusaponin IVa, chikusetsusaponin IVa methyl ester and oleanolic acid-3,28-beta-diglucopyranoside. The structures of the isolated compounds were verified by means of MS and NMR spectral analyses. PMID:11454355

Kamel, M S; Mohamed, K M; Hassanean, H A; Ohtani, K; Kasai, R; Yamasaki, K

2001-08-01

147

New minor glycoside components from saffron.  

PubMed

Phytochemical investigation of the stigmas of Crocus sativus resulted in the isolation of eight glycosides (1-8) including a new safranal glycoside (2) and a new carotenoid pigment (6). The structures of the new compounds were identified as (4R)-4-hydroxy-2,6,6-trimethylcyclohex-1-enecarbaldehyde 4-O-[?-D-glucopyranosyl(1 ? 3)-?-D-glucopyranoside] (2) and trans-crocetin-1-al 1-O-?-gentiobiosyl ester (6) on the basis of extensive chemical and spectroscopic evidence. PMID:23179314

Tung, Nguyen Huu; Shoyama, Yukihiro

2013-07-01

148

Bioactive phenylpropanoid glycosides from Tabebuia avellanedae.  

PubMed

Three novel phenylpropanoid glycosides 2, 5, 6 were isolated from water extract of Tabebuia avellanedae, together with three known phenylpropanoid glycosides 1, 3, 4. All compounds were identified on the basis of spectroscopic analysis and chemical methods and, for known compounds, by comparison with published data. All isolated compounds showed strong antioxidant activity in the DPPH assay, and compound 5 give the highest antioxidant activity among all compounds, with an IC?? of 0.12 µM. All compounds exhibited moderate inhibitory effect on cytochrome CYP3A4 enzyme. PMID:23797703

Suo, Maorong; Ohta, Tomihisa; Takano, Fumihide; Jin, Shouwen

2013-01-01

149

Elemanolide sesquiterpenes and eudesmane sesquiterpene glycosides from Centaurea hierapolitana.  

PubMed

Two elemanolide sesquiterpenes and two eudesmane-type sesquiterpene glycosides named hierapolitanins A-D, were isolated, together with five known compounds, two flavones; hispidulin and jaceosidin, a flavon-C-glycoside, shaftoside, a flavonol glycoside, kaempferol-3-O-rutinoside and a neolignan, dehydrodiconiferyl alcohol from the aerial parts of Centaurea hierapolitana Boiss. (Asteraceae). Structure elucidations were based on spectroscopic evidence. PMID:17126864

Karamenderes, Canan; Bedir, Erdal; Pawar, Rahul; Baykan, Sura; Khan, Ikhlas A

2007-03-01

150

Genetic Manipulation of Condensed Tannins in Higher Plants1  

PubMed Central

We have produced and analyzed transgenic birdsfoot trefoil (Lotus corniculatus L.) plants harboring antisense dihydroflavonol reductase (AS-DFR) sequences. In initial experiments the effect of introducing three different antisense Antirrhinum majus L. DFR constructs into a single recipient genotype (S50) was assessed. There were no obvious effects on plant biomass, but levels of condensed tannins showed a statistical reduction in leaf, stem, and root tissues of some of the antisense lines. Transformation events were also found, which resulted in increased levels of condensed tannins. In subsequent experiments a detailed study of AS-DFR phenotypes was carried out in genotype S33 using pMAJ2 (an antisense construct comprising the 5? half of the A. majus cDNA). In this case, reduced tannin levels were found in leaf and stem tissues and in juvenile shoot tissues. Analysis of soluble flavonoids and isoflavonoids in tannin down-regulated shoot tissues indicated few obvious default products. When two S33 AS-DFR lines were outcrossed, there was an underrepresentation of transgene sequences in progeny plants and no examples of inheritance of an antisense phenotype were observed. To our knowledge, this is the first report of the genetic manipulation of condensed tannin biosynthesis in higher plants.

Robbins, Mark P.; Bavage, Adrian D.; Strudwicke, Catherine; Morris, Phillip

1998-01-01

151

Two new glycosidic acids, quamoclinic acids G and H, of the resin glycosides (Convolvulin) from the seeds of Quamoclit pennata.  

PubMed

Two new glycosidic acids, quamoclinic acids G and H, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction from the seeds of Quamoclit pennata BOJER. Both compounds are the first examples of bisdesmosides of glycosidic acid having the sugar linkages at C-3 of 3,11-dihydroxytetradecanoic acid (ipurolic acid) as well as at its C-11. PMID:20823606

Ono, Masateru; Imao, Masae; Miyahara, Kazumoto

2010-09-01

152

Identification and characterization of component organic and glycosidic acids of crude resin glycoside fraction from Calystegia soldanella.  

PubMed

Alkaline hydrolysis of the crude resin glycoside fraction of the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae) gave four new glycosidic acids, named calysolic acids A, B, C, and D, along with one known glycosidic acid, soldanellic acid B, and three organic acids, 2S-methylbutyric, tiglic, and 2S,3S-nilic acids. The structures of the new glycosidic acids were characterized on the basis of spectroscopic data and chemical evidence. PMID:21881263

Takigawa, Ayako; Setoguchi, Hiroaki; Okawa, Masafumi; Kinjo, Junei; Miyashita, Hiroyuki; Yokomizo, Kazumi; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ono, Masateru

2011-01-01

153

Two new maltol glycosides and cyanogenic glycosides from Elsholtzia rugulosa Hemsl.  

PubMed

Two new maltol glycosides, maltol 6'-O-beta-D-apiofuranosyl-beta-D-glucopyranoside and maltol 6'-O-(5-O-p-coumaroyl)-beta-D-apiofuranosyl-beta-D-glucopyranoside, were isolated from Elsholtzia rugulosa Hemsl. along with 11 known compounds including prunasin and amygdalin. The structures were determined on the basis of spectroscopic and chemical evidence. This is the second example of isolation of cyanogenic glycosides from Lamiaceous plants. PMID:18404347

Li, Haizhou; Nakashima, Tatsuya; Tanaka, Takashi; Zhang, Ying-Jun; Yang, Chong-Ren; Kouno, Isao

2008-01-01

154

Pregnane glycosides from fruits of Balanites aegyptiaca  

Microsoft Academic Search

From the mesocarp of Balanites aegyptiaca fruits, two pregnane glycosides were isolated. One is new and identified as pregn-5-ene-3?,16?,20(R)-triol 3-O-(2,6-di-O-?-l-rhamnopyranosyl)-?-d-glucopyranoside (balagyptin), while the other is known and assigned as pregn-5-ene-3?,16?,20(R)-triol 3-O-?-d-glucopyranoside.

M. S. Kamel; A. Koskinen

1995-01-01

155

A new lignan glycoside from Peperomia duclouxii.  

PubMed

A new lignan glycoside was isolated from the n-BuOH extract of Peperomia duclouxii C. DC., and its structure was elucidated to be 2-(4''-hydroxy-3'', 5''-dimethoxybenzyl)-3-(5'-methoxy-3', 4'-methylenedioxybenzyl)butyrolactone-4''-O-beta-D-glucopyranoside (1) by spectral methods. PMID:19023812

Zhu, Yan Hui; Li, Na; Wang, Ming-Wei

2008-01-01

156

A new chromene glycoside from Tithonia diversifolia  

Microsoft Academic Search

A new chromene glycoside, 6-acetyl-2,2-dimethylchromene-8-O-?-D-glucoside, together with four known compounds were isolated from the aerial parts of Tithonia diversifolia. Their structures\\u000a were established by 1H, 13C NMR, and HMQC together with the other physical and chemical investigations.

Hong-li Zhai; Gui-jun Zhao; Gen-jin Yang; He Sun; Bo Yi; Lian-na Sun; Wan-sheng Chen; Shui-qing Zheng

2010-01-01

157

Chlorination Diversifies Cimicifuga racemosa Triterpene Glycosides  

PubMed Central

Extracts from roots and rhizomes of black cohosh (Cimicifuga racemosa) are widely used as dietary supplements to alleviate menopausal symptoms. State-of-the-art QC measures involve phytochemical fingerprinting of the triterpene glycosides for species identification and chemical standardization by HPLC. In the course of developing materials and methods for standardization procedures, the major C. racemosa triterpene glycoside (1) was isolated ans initially thought to be cimicifugoside (2). Detailed HR-LC-MS and 1/2D NMR analysis of 1 and 2 unambiguously revealed that 1 is its chlorine-containing derivative of 2, namely 25-chlorodeoxycimigenol-3-O-?-D-xyloside. Accordingly, HPLC profiles of black cohosh preparations require revision of the assignments of the chlorinated (1) and non-chlorinated (2) pair. Besides explaining the substantial shift in polarity (?tR[RP-18] ca 20 min), 25-deoxychlorination opens a new pathway of structural diversification in triterpene glycosides chemistry. As chemical conversion of 2 into 1 could be demonstrated, deoxychlorination may be interpreted as artifact formation. Simultaneously, however, it is a potentially significant pathway for the gastric in vivo conversion (“nature's pro drug”) of the relatively polar triterpene glycosides into significantly less polar chlorinated derivatives with altered pharmacological properties.

Chen, Shao-Nong; Lankin, David C.; Nikolic, Dejan; Fabricant, Daniel S.; Lu, Zhi-Zhen; Ramirez, Benjamin; van Breemen, Richard B.; Fong, Harry H. S.; Farnsworth, Norman R.; Pauli, Guido F.

2008-01-01

158

?-Chymotrypsin inhibiting benzylated glycosides from Symplocos racemosa  

Microsoft Academic Search

Three new benzylated glycosides, locoracemosides A, B and C (1–3) were isolated from the bark of the stem of Symplocos racemosa Roxb. Their structures were determined by spectroscopic and chemical evidences. They displayed in vitro inhibitory activity against ?-chymotrypsin.

Muhammad A. Rashid; Viqar U. Ahmad; Muhammad A. Abbasi; Zulfiqar Ali; Nasir Rasool; Muhammad Zubair; Muhammad A. Lodhi; Muhammad I. Choudhary; Ikhlas A. Khan

2008-01-01

159

A new withanolide glycoside from physalis peruviana  

PubMed

A new withanolide glycoside, 17beta-hydroxy-14, 20-epoxy-1-oxo-[22R]-3beta-[O-beta-D-glucopyranosyl]-witha-5, 24-dienolide (1), has been isolated from the whole plant of Physalis peruviana. Its identity was determined using a combination of spectroscopic data including 2D NMR techniques and chemical transformations. PMID:10096867

Ahmad; Malik; Afza; Yasmin

1999-03-01

160

Nivyaside — A new glycoside from Leucanthemum vulgare  

Microsoft Academic Search

From the ligulate flowers ofLeucanthemum vulgare Lam. growing on the territory of the Georgian SSR a new glycoside has been isolated which has been called nivyaside and has\\u000a the structure 8-(1-?-D-glucopyranosyl-5-deoxyquercit-5-yl)-4?,5,7-trihydroxyflavone.

T. G. Sagareishvili; M. D. Alaniya; V. S. Kikoladze; É. P. Kemertelidze

1982-01-01

161

Two New Caffeyol Glycosides from Forsythia suspensa  

Microsoft Academic Search

Two new caffeoyl glycosides of phenethyl alcohol, suspensaside A (1) and suspensaside B (2), were isolated from the fruits of Forsythia suspensa. Also obtained in this investigation were two known compounds forsythiaside (3) and suspensaside (4). The structures of compounds 1 and 2 were established by 1D and 2D NMR techniques and chemical methods.

Dong-Sheng Ming; De-Quan Yu; Shi-Shan Yu

1999-01-01

162

New triterpene glycosides from Ziziphi Spinosae Semen.  

PubMed

Four new dammarane-type triterpene glycosides, named jujubosides I-IV (1-4), were isolated from Ziziphi Spinosae Semen, along with seven known saponins (5-11). The structures of new compounds were established on the basis of extensive spectroscopic analysis. All compounds were evaluated for the effects on neonatal rat cardiomyocyte injury induced by hydrogen peroxide in vitro. PMID:23912064

Wang, Yu; Ding, Bo; Luo, Dan; Chen, Liu-Yuan; Hou, Yun-Long; Dai, Yi; Yao, Xin-Sheng

2013-10-01

163

A new aromatic glycoside from Glehnia littoralis.  

PubMed

A new aromatic glycoside (1) was isolated from the roots of Glehnia littoralis Fr. Schmidtex Miq. Its structure was elucidated as vanillic acid 1-O-[?-D-apiofuranosyl-(1 ? 6)-?-D-glucopyranoside] ester mainly by analysing the NMR and MS spectral data. In the in vitro assays, compound 1 displayed some TNF-? secretion inhibitory activity. PMID:24547738

Feng, Zi-Jin; Zhang, Xiao-Hong; Zhang, Jian-Peng; Shang, Xiao-Hui; Gao, Yun; Lu, Xiao-Ling; Liu, Xiao-Yu; Jiao, Bing-Hua

2014-01-01

164

Two methoxylated flavone glycosides from Bidens pilosa  

Microsoft Academic Search

Two methoxylated flavone glycosides were identified as the novel quercetin 3,3?-dimethyl ether 7-O-?-d-rhamnopyranosyl-(1 ? 6)-?-d-glucopyranoside and the known quercetin 3,3?-dimethyl ether 7-O-?-d-glucopyranoside from the roots of Bidens pilosa.

M. G. L. Brandão; C. G. C. Nery; M. A. S. Mamão; A. U. Krettli

1998-01-01

165

Enzymatic Processing of Bioactive Glycosides from Natural Sources  

NASA Astrophysics Data System (ADS)

A number of biologically active natural products are glycosides. Often, the glycosidic residue is crucial for their activity. In other cases, glycosylation only improves their pharmacokinetic parameters. Enzymatic modification of these glycosides - both extension of the glycoside moiety and its selective trimming - is advantageous due to their selectivity and mildness of the reaction conditions in the presence of reactive and sensitive complex aglycones. Enzymatic reactions enable the resulting products to be used as "natural products", e.g., in nutraceuticals. This chapter concentrates on naturally occurring glycosides used in medicine but also in the food and flavor industry (e.g., sweeteners). Both "classical" and modern methods will be discussed.

Weignerová, Lenka; K?en, Vladimír

166

Use of antioxidants in extraction of tannins from walnut plants.  

PubMed

The radial diffusion assay was applied to estimate the amount of total tannins in extracts from walnut plant materials. We found that the protein-precipitating activity of the tannin extracts were increased by 30-75 % when antioxidants (ascorbic acid or sodium metabisulfite, 5.5 mM) were added in extraction solvents (50% aqueous methanol). The extracts obtained with Na2S2O5 were much less brown than control. Moreover, two-dimensional thin-layer chromatography revealed some additional polyphenolic compounds in the extracts made with Na2S2O5. These results suggest that the amount of tannins and/or their protein-precipitating property may be strongly affected by oxidation events during extraction procedure. The addition of antioxidants in the extraction solvents is useful to limit this problem. PMID:24259073

Peng, S; Jay-Allemand, C

1991-05-01

167

Tannins in faba beans (Vicia Faba L.)- antinutritional properties in monogastric animals  

Microsoft Academic Search

Condensed tannins are found in coloured-flowering varieties of faba beans ( Vicia<\\/u>faba<\\/u> L.). They are considered as antinutritional factors for nonruminant species. High-tannin hulls of faba beans and isolated tannins were shown to induce a rapid hypertrophy of the parotid glands in rats and increase the secretion of salivary proline-rich proteins with a high affinity for tannins. In this way

A. J. M. Jansman

1993-01-01

168

Effect of Condensed Tannins on Bacterial Diversity and Metabolic Activity in the Rat Gastrointestinal Tract  

Microsoft Academic Search

The effect of dietary condensed tannins (proanthocyanidins) on rat fecal bacterial populations was ascer- tained in order to determine whether the proportion on tannin-resistant bacteria increased and if there was a change in the predominant bacterial populations. After 3 weeks of tannin diets the proportion of tannin- resistant bacteria increased significantly (P < 0.05) from 0.3% 5.5% to 25.3% 8.3%

Alexandra H. Smith; Roderick I. Mackie

2004-01-01

169

Characterization of Tannin-tolerant Bacterial Isolates from East African Ruminants  

Microsoft Academic Search

Several tannin-tolerant bacteria were isolated from enrichment cultures of rumen microflora of bush duiker, giraffe, Grant's gazelle, sheep, and goat, and established in medium containing crude tannin extracts or tannic acid. The isolates were characterized by classical and molecular methods. The isolates were also tested for the presence of tannin acylhydrolase. Characterization by restriction fragment length polymorphism of the 16S

Agnes A. Odenyo; Richard Bishop; Genet Asefa; Ramni Jamnadass; David Odongo; Paschal Osuji

2001-01-01

170

[Role of Ca-calmodulin- and cAMP-dependent reactions in forming the cardiac cycle].  

PubMed

The mechanisms of regulation of calcium ion concentration in the heart muscle during cardiac cycle have been considered. A great deal of attention has been devoted to the interaction of Ca2+-calmodulin- and cAMP-dependent reactions in the heart contraction-relaxation processes. The hypothesis on the two-phase structure of cardiac cycle has been proposed. This hypothesis allows to explain some biochemical mechanisms in the positive inotropic effect of catecholamines, cardiac glycosides and caffeine. PMID:2827793

Laptev, B I; Prokop'eva, V D; Bogomaz, S A

1987-01-01

171

Growth of broiler chicks fed diets containing tannin-free and tannin-containing near-isogenic lines of Faba bean (Vicia Faba L.)  

Microsoft Academic Search

Seeds from six pairs of near-isogenic lines of Vicia faba L., each pair consisting of a tannin-free (TF) and a tannin-containing (TC) partner line, were used to study the effect of breeding for the absence of condensed tannins on the seed content of dry matter (DM), crude protein (CP), and starch (S), on in vitro protein digestibility (IVPD) and on

Johannes P. F. G. Helsper; Loon van Y. P. J; René P. Kwakkel; Arend van Norel; Poel van der A. F. B

1996-01-01

172

Response of ?? T cells to plant-derived tannins  

PubMed Central

Many pharmaceutical drugs are isolated from plants used in traditional medicines. Through screening plant extracts, both traditional medicines and compound libraries, new pharmaceutical drugs continue to be identified. Currently, two plant-derived agonists for ?? T cells are described. These plant-derived agonists impart innate effector functions upon distinct ?? T cell subsets. Plant tannins represent one class of ?? T cell agonist and preferentially activate the mucosal population. Mucosal ?? T cells function to modulate tissue immune responses and induce epithelium repair. Select tannins, isolated from apple peel, rapidly induce immune gene transcription in ?? T cells, leading to cytokine production and increased responsiveness to secondary signals. Activity of these tannin preparations tracks to the procyanidin fraction, with the procyanidin trimer (C1) having the most robust activity defined to date. The response to the procyanidins is evolutionarily conserved in that responses are seen with human, bovine, and murine ?? T cells. Procyanidin-induced responses described in this review likely account for the expansion of mucosal ?? T cells seen in mice and rats fed soluble extracts of tannins. Procyanidins may represent a novel approach for treatment of tissue damage, chronic infection, and autoimmune therpies.

Holderness, Jeff; Hedges, Jodi F.; Daughenbaugh, Katie; Kimmel, Emily; Graff, Jill; Freedman, Brett; Jutila, Mark A.

2008-01-01

173

Changes in the structural composition and reactivity of Acer rubrum leaf litter tannins exposed to warming and altered precipitation: climatic stress-induced tannins are more reactive.  

PubMed

• Climate change could increase the frequency with which plants experience abiotic stresses, leading to changes in their metabolic pathways. These stresses may induce the production of compounds that are structurally and biologically different from constitutive compounds. • We studied how warming and altered precipitation affected the composition, structure, and biological reactivity of leaf litter tannins in Acer rubrum at the Boston-Area Climate Experiment, in Massachusetts, USA. • Warmer and drier climatic conditions led to higher concentrations of protective compounds, including flavonoids and cutin. The abundance and structure of leaf tannins also responded consistently to climatic treatments. Drought and warming in combination doubled the concentration of total tannins, which reached 30% of leaf-litter DW. This treatment also produced condensed tannins with lower polymerization and a greater proportion of procyanidin units, which in turn reduced sequestration of tannins by litter fiber. Furthermore, because of the structural flexibility of these tannins, litter from this treatment exhibited five times more enzyme (?-glucosidase) complexation capacity on a per-weight basis. Warmer and wetter conditions decreased the amount of foliar condensed tannins. • Our finding that warming and drought result in the production of highly reactive tannins is novel, and highly relevant to climate change research as these tannins, by immobilizing microbial enzymes, could slow litter decomposition and thus carbon and nutrient cycling in a warmer, drier world. PMID:21371041

Tharayil, Nishanth; Suseela, Vidya; Triebwasser, Daniella J; Preston, Caroline M; Gerard, Patrick D; Dukes, Jeffrey S

2011-07-01

174

Fast-Setting Phenolic and Tannin-Based 'Honeymoon' Adhesive Systems for Exterior Grade Finger-Joints.  

National Technical Information Service (NTIS)

This study describes the development of alternative tannin-based fast-setting adhesives not containing m-aminophenol as well as of phenolic/phenolic, tannin/tannin and tannin/phenolic adhesive systems which can be used for the same purpose.

A. Pizzi D. D. T. Rossouw W. Knueffel M. Singmin

1980-01-01

175

Effects of dietary tannic acid and quebracho tannin on growth performance and metabolic rates of common carp ( Cyprinus carpio L.)  

Microsoft Academic Search

The effects of tannic acid (a hydrolysable tannin) and quebracho tannin (a condensed tannin) on common carp at a level of 2% in a soybean and fish meal-based diet containing about 40% crude protein have been studied. Quebracho tannin did not affect feed intake, body weight gain, average metabolic growth rate and oxygen consumption during the experimental period (84 days).

Klaus Becker; H. P. S Makkar

1999-01-01

176

Tannin concentration enhances seed caching by scatter-hoarding rodents: An experiment using artificial ‘seeds’  

NASA Astrophysics Data System (ADS)

Tannins are very common among plant seeds but their effects on the fate of seeds, for example, via mediation of the feeding preferences of scatter-hoarding rodents, are poorly understood. In this study, we created a series of artificial 'seeds' that only differed in tannin concentration and the type of tannin, and placed them in a pine forest in the Shangri-La Alpine Botanical Garden, Yunnan Province of China. Two rodent species ( Apodemus latronum and A. chevrieri) showed significant preferences for 'seeds' with different tannin concentrations. A significantly higher proportion of seeds with low tannin concentration were consumed in situ compared with seeds with a higher tannin concentration. Meanwhile, the tannin concentration was significantly positively correlated with the proportion of seeds cached. The different types of tannin (hydrolysable tannin vs condensed tannin) did not differ significantly in their effect on the proportion of seeds eaten in situ vs seeds cached. Tannin concentrations had no significant effect on the distance that cached seeds were carried, which suggests that rodents may respond to different seed traits in deciding whether or not to cache seeds and how far they will transport seeds.

Wang, Bo; Chen, Jin

2008-11-01

177

High-performance liquid chromatography determination of red wine tannin stickiness.  

PubMed

Red wine astringency is generally considered to be the sensory result of salivary protein precipitation following tannin-salivary protein interaction and/or tannin adhering to the oral mucosa. Astringency in red wine is often described using qualitative terms, such as hard and soft. Differences in qualitative description are thought to be due in part to the tannin structure. Tannin chemistry contributions to qualitative description have been shown to correlate with the enthalpy of interaction between tannin and a hydrophobic surface. On the basis of these findings, a method was developed that enabled the routine determination of the thermodynamics of the tannin interaction with a hydrophobic surface (polystyrene divinylbenzene) for tannins in red wine following direct injection. The optimized analytical method monitored elution at four different column temperatures (25-40 °C, in 5 °C increments), had a 20 min run time, and was monitored at 280 nm. The results of this study confirm that the calculated thermodynamics of the interaction are intensive and, therefore, provide specific thermodynamic information. Variation in the enthalpy of interaction between tannin and a hydrophobic surface (tannin stickiness) is a unique, concentration-independent analytical parameter. The method, in addition to providing information on tannin stickiness, provides the tannin concentration. PMID:24959945

Revelette, Matthew R; Barak, Jennifer A; Kennedy, James A

2014-07-16

178

Five phenolic glycosides from Alangium chinense.  

PubMed

From the dried leaves of Alangium chinense, five novel phenolic glycosides, 6'-O-galloylsalicin (1); 4',6'-di-O-galloylsalicin (2); 4',6'-O-(S)-hexahydroxydiphenoylsalicin (3); 4', 6'-O-(R)-hexahydroxydiphenoylsalicin (4); and pyrocatechol 1-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranoside (5) were isolated. The structures of these new compounds were determined by spectroscopic methods. PMID:10650086

Itoh, A; Tanahashi, T; Ikejima (née Sato), S; Inoue, M; Nagakura, N; Inoue, K; Kuwajima, H; Wu, H X

2000-01-01

179

Pregnane glycosides from fruits of Balanites aegyptiaca.  

PubMed

From the mesocarp of Balanites aegyptiaca fruits, two pregnane glycosides were isolated. One is new and identified as pregn-5-ene-3 beta,16 beta,20(R)-triol 3-O-(2,6-di-O-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside (balagyptin), while the other is known and assigned as pregn-5-ene-3 beta,16 beta,20(R)-triol 3-O-beta-D-glucopyranoside. PMID:8590640

Kamel, M S; Koskinen, A

1995-12-01

180

New xanthone glycosides from Comastoma pedunculatum.  

PubMed

Five new xanthone glycosides, comastomasides A-E (1-5), were isolated from aqueous ethanol extracts of the aerial portions of Comastoma pedunculatum. The structures of these compounds were elucidated by spectroscopic analysis methods. Compounds 1-5 were evaluated for their hepatoprotective activity and cytotoxicity against four human cancer cell lines by in vitro assays. Among them, compounds 3 and 5 exhibited potent hepatoprotective activity. However, none of the compounds displayed cytotoxic activity. PMID:22814820

Qiao, Yongqi; Yuan, Yi; Cui, Baosong; Zhang, Ying; Chen, Hui; Li, Shuai; Li, Yan

2012-09-01

181

Laccase-mediated oxidation of natural glycosides  

Microsoft Academic Search

Regioselective oxidations of the primary OH's of natural glycosides (thiocolchicoside, colchicoside, amygdalin, asiaticoside, ginsenoside RE) have been performed on a preparative scale by exploiting the laccase–2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) methodology. The influence of water-miscible organic cosolvents on the stability and activity of a laccase from Trametes pubescens has been investigated. The enzyme has been covalently linked to Eupergit C250L and its performances

Lara Baratto; Andrea Candido; Mattia Marzorati; Francesca Sagui; Sergio Riva; Bruno Danieli

2006-01-01

182

A phenylpropanoid glycoside from Ballota nigra.  

PubMed

A new phenylpropanoid glycoside, ballotetroside, has been isolated from the aerial parts of Ballota nigra. On the basis of chemical and spectral data, its structure has been established as (3,4-dihydroxyphenyl)-2-ethyl[alpha-L-arabinopyranosyl-(1-->2)-alp ha- L-rhamnopyranosyl-(1-->3)]-beta-D-apiofuranosyl-(1-->6)-4-O- caffeoyl-beta-D-glucopyranoside. PMID:9041717

Seidel, V; Bailleul, F; Libot, F; Tillequin, F

1997-02-01

183

New jujubogenin glycosides from Colubrina asiatica.  

PubMed

Three new jujubogenin glycosides, namely, 3' '-O-acetylcolubrin (1); 3' ',2' "-O-diacetylcolubrin (2), and 3' '-O-acetyl-6' '-O-trans-crotonylcolubrin (3), were isolated from the leaves of Colubrina asiatica, in addition to the known colubrin, rutin, and kaempferol 3-O-rutinoside. Compounds 1-3 were isolated and purified via a combination of chromatographic procedures, and determined structurally using spectroscopic methods. PMID:11087616

Lee, S S; Chen, W C; Chen, C H

2000-11-01

184

?-cyclodextrin assistant flavonoid glycosides enzymatic hydrolysis  

PubMed Central

Background: The content of icaritin and genistein in herba is very low, preparation with relatively large quantities is an important issue for extensive pharmacological studies. Objective: This study focuses on preparing and enzymic hydrolysis of flavonoid glycosides /?-cyclodextrin inclusion complex to increase the hydrolysis rate. Materials and Methods: The physical property of newly prepared inclusion complex was tested by differential scanning calorimetry (DSC). The conditions of enzymatic hydrolysis were optimized for the bioconversion of flavonoid glycosides /?-cyclodextrin inclusion complex by mono-factor experimental design. The experiments are using the icariin and genistein as the model drugs. Results: The solubility of icariin and genistein were increased almost 17 times from 29.2 ?g/ml to 513.5 ?g/ml at 60°C and 28 times from 7.78 ?g/ml to 221.46 ?g/ml at 50°C, respectively, demonstrating that the inclusion complex could significantly increase the solubility of flavonoid glycosides. Under the optimal conditions, the reaction time of icariin and genistin decreased by 68% and 145%, when compared with that without ?-CD inclusion. By using this enzymatic condition, 473 mg icaritin (with the purity of 99.34%) and 567 mg genistein(with the purity of 99.46%), which was finally determined by melt point, ESI-MS, UV, IR, 1H NMR and 13C NMR, was obtained eventually by transforming the inclusion complex(contains 1.0 g substrates). Conclusion: This study can clearly indicate a new attempt to improve the speed of enzyme-hydrolysis of poorly water-soluble flavonoid glycosides and find a more superior condition which is used to prepare icaritin and genistein.

Jin, Xin; Zhang, Zhen-hai; Sun, E.; Jia, Xiao-Bin

2013-01-01

185

Phenotypic and phylogenetic characterization of ruminal tannin-tolerant bacteria.  

PubMed

The 16S rRNA sequences and selected phenotypic characteristics were determined for six recently isolated bacteria that can tolerate high levels of hydrolyzable and condensed tannins. Bacteria were isolated from the ruminal contents of animals in different geographic locations, including Sardinian sheep (Ovis aries), Honduran and Colombian goats (Capra hircus), white-tail deer (Odocoileus virginianus) from upstate New York, and Rocky Mountain elk (Cervus elaphus nelsoni) from Oregon. Nearly complete sequences of the small-subunit rRNA genes, which were obtained by PCR amplification, cloning, and sequencing, were used for phylogenetic characterization. Comparisons of the 16S rRNA of the six isolates showed that four of the isolates were members of the genus Streptococcus and were most closely related to ruminal strains of Streptococcus bovis and the recently described organism Streptococcus gallolyticus. One of the other isolates, a gram-positive rod, clustered with the clostridia in the low-G+C-content group of gram-positive bacteria. The sixth isolate, a gram-negative rod, was a member of the family Enterobacteriaceae in the gamma subdivision of the class Proteobacteria. None of the 16S rRNA sequences of the tannin-tolerant bacteria examined was identical to the sequence of any previously described microorganism or to the sequence of any of the other organisms examined in this study. Three phylogenetically distinct groups of ruminal bacteria were isolated from four species of ruminants in Europe, North America, and South America. The presence of tannin-tolerant bacteria is not restricted by climate, geography, or host animal, although attempts to isolate tannin-tolerant bacteria from cows on low-tannin diets failed. PMID:9758806

Nelson, K E; Thonney, M L; Woolston, T K; Zinder, S H; Pell, A N

1998-10-01

186

Thermodynamics of grape and wine tannin interaction with polyproline: implications for red wine astringency.  

PubMed

The astringency of red wine is largely due to the interaction between wine tannins and salivary proline-rich proteins and is known to change as wine ages. To further understand the mechanisms behind wine astringency change over time, thermodynamics of the interactions between poly(l-proline) (PLP) and grape seed and skin tannins (preveraison (PV) and commercially ripe) or Shiraz wine tannins (2 years old and 9-10 years old) was analyzed using isothermal titration calorimetry (ITC). The nature of these interactions varied with changes to the tannin structure that are associated with maturation. The change in enthalpy associated with hydrophobic interaction and hydrogen bonding decreased with tannin age and the stoichiometry of binding indicated that grape tannins associated with more proline residues than wine tannins, irrespective of molecular size. These results could provide an explanation for the observed change in wine astringency quality with age. PMID:21070019

McRae, Jacqui M; Falconer, Robert J; Kennedy, James A

2010-12-01

187

Cyanogenic glycosides: a case study for evolution and application of cytochromes P450  

Microsoft Academic Search

Cyanogenic glycosides are ancient biomolecules found in more than 2,650 higher plant species as well as in a few arthropod species. Cyanogenic glycosides are amino acid-derived ?-glycosides of ?-hydroxynitriles. In analogy to cyanogenic plants, cyanogenic arthropods may use cyanogenic glycosides as defence compounds. Many of these arthropod species have been shown to de novo synthesize cyanogenic glycosides by biochemical pathways

Søren Bak; Susanne Michelle Paquette; Marc Morant; Anne Vinther Morant; Shigeki Saito; Nanna Bjarnholt; Mika Zagrobelny; Kirsten Jørgensen; Sarah Osmani; Henrik Toft Simonsen; Raquel Sanchez Pérez; Torbjørn Bordier van Heeswijck; Bodil Jørgensen; Birger Lindberg Møller

2006-01-01

188

Alkyl and phenolic glycosides from Saussurea stella.  

PubMed

One alkyl glycoside, saussurostelloside A (1), two phenolic glycosides, saussurostellosides B1 (2) and B2 (3), and 27 known compounds, including eleven flavonoids, seven phenolics, six lignans, one neolignan, one phenethyl glucoside and one fatty acid, were isolated from an ethanol extract of Saussurea stella (Asteraceae). Their structures were elucidated by NMR, MS, UV, and IR spectroscopic analysis. Of the known compounds, (+)-medioresinol-di-O-?-d-glucoside (7), picraquassioside C (10), and diosmetin-3'-O-?-d-glucoside (27) were isolated from the Asteraceae family for the first time, while (+)-pinoresinol-di-O-?-d-glucoside (6), di-O-methylcrenatin (11), protocatechuic acid (14), 1,5-di-O-caffeoylquinic acid (17), formononetin (28), and phenethyl glucoside (29) were isolated from the Saussurea genus for the first time. The anti-inflammatory activities of three new compounds (1-3), five lignans ((-)-arctiin (4), (+)-pinoresinol-4-O-?-d-glucoside (5), (+)-pinoresinol-di-O-?-d-glucoside (6), (+)-medioresinol-di-O-?-d-glucoside (7) and (+)-syringaresinol-4-O-?-d-glucoside (8)), one neolignan (picraquassioside C (10)), and one phenolic glycoside (di-O-methylcrenatin (11)) were evaluated by testing their inhibition of the release of ?-glucuronidase from PAF-stimulated neutrophils. Only compound 5 showed moderate inhibition of the release of ?-glucuronidase, with an inhibition ratio of 39.1%. PMID:23567860

Wang, Tian-Min; Wang, Ru-Feng; Chen, Hu-Biao; Shang, Ming-Ying; Cai, Shao-Qing

2013-04-01

189

Interactions between oak tannins and parasite community structure: Unexpected benefits of tannins to cynipid gall-wasps  

Microsoft Academic Search

Plant species vary tremendously in the number of phytophagous species they support. May (1979) and Price (1980) proposed that some of this variation may be due to variation in biochemical defenses. We find that variation between oak species in leaf tannin levels is positively correlated with 1) variation in the numbers of species of leaf-galling cynipid wasps those trees host;

M. L. Taper; T. J. Case

1987-01-01

190

Vasorelaxant activity of 7-?-O-glycosides biosynthesized from flavonoids.  

PubMed

In this work we report the vasorelaxant activity of 7-?-O-glycosides obtained with biosynthesis of naringenin-7-?-O-glycoside (3) and quercetin-7-?-O-glycoside (4). These compounds were obtained from naringenin (1) and quercetin (2) glycosylation catalyzed by Beauveria bassiana ATCC 7159. Screening of the best strain as a catalyst for glycosylation was carried out and the reaction conditions established. Cultures were grown in PDSM medium for 7 days at 27°C. After purification by reverse-phase preparative HPLC, naringenin-7-?-O-glycoside (3) and quercetin-7-?-O-glycoside (4) were identified by (1)H and (13)C NMR. The right position and ?-configuration of the glucose was determined through HSQC and HMBC experiments. The vasorelaxation potential of naringenin, quercetin and its glycosylated derivatives was evaluated using isolated aorta in vitro models. Interestingly, results suggest that vasorelaxation properties of naringenin, rutin and its glycosides are due to different pathways. PMID:24704375

Penso, Juliana; Cordeiro, Kelly C F A; da Cunha, Carla R M; da Silva Castro, Patricia F; Martins, Daniella R; Lião, Luciano M; Rocha, Matheus L; de Oliveira, Valéria

2014-06-15

191

New oxypregnane glycosides from appetite suppressant herbal supplement Hoodia gordonii  

Microsoft Academic Search

Hoodigosides A–K (1–11), eleven new oxypregnane glycosides and a previously reported oxypregnane glycoside P57AS3 were isolated from the aerial parts of Hoodia gordonii. The structures of these 12-O-?-tigloyl isoramanone glycosides were determined on the basis of chemical evidence and extensive spectroscopic methods that include one-dimensional and two-dimensional NMR. Cytotoxicity and antioxidant activities of these compounds were tested in cell based

Rahul S. Pawar; Yatin J. Shukla; Shabana I. Khan; Bharathi Avula; Ikhlas A. Khan

2007-01-01

192

Phenolic glycosides from Symplocos racemosa: natural inhibitors of phosphodiesterase I  

Microsoft Academic Search

One new phenolic glycoside named benzoylsalireposide (1) along with one known phenolic glycoside named salireposide (2) have been isolated from Symplocos racemosa. Four other known compounds i.e. ?-amyrin (3), oleonolic acid (4), ?-sitosterol (5) and ?-sitosterol glycoside (6) were also isolated from this plant. The structure elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR analysis, including

Viqar Uddin Ahmad; Muhammad Athar Abbasi; Hidayat Hussain; Muhammad Nadeem Akhtar; Umar Farooq; Naheed Fatima; M. Iqbal Choudhary

2003-01-01

193

Lignan and neolignan glycosides from the roots of Glehnia littoralis.  

PubMed

A new lignan glycoside [glehlinoside G (1)] and three new neolignan glycosides [glehlinosides H (2), I (3) and J (4)] were isolated from the roots of Glehnia littoralis. Their structures were elucidated on the basis of spectroscopic data. The above glehlinosides (1-4), together with the other lignan and neolignan glycosides (5-12) from this plant, were evaluated for their prolyl oligopeptidase inhibitory activities, and a caffeoyled lignan glycoside (glehlinoside F, 8) exhibited a noticeable activity (IC(50) = 14.5?µM). PMID:20560111

Xu, Yi; Gu, Xue; Yuan, Zhong

2010-10-01

194

A chlorinated monoterpene ketone, acylated beta-sitosterol glycosides and a flavanone glycoside from Mentha longifolia (Lamiaceae).  

PubMed

Mentha longifolia (Lamiaceae), an aromatic herb yielded a new halogenated chloro-derivative of menthone (longifone), two new derivatives of beta-sitosterol glycoside (longiside-A and -B) and a new flavanone-glycoside (longitin). The beta-sitosterol and flavanone glycosides were purified as their acetate derivatives. Structures of all the isolated constituents were elucidated with the aid of HMBC techniques. However, the structure of longifone was also determined through X-ray crystallography. PMID:11937172

Shaiq Ali, Muhammad; Saleem, Muhammad; Ahmad, Waqar; Parvez, Masood; Yamdagni, Raghav

2002-04-01

195

Retention of tannic acid and condensed tannin by Fe-oxide-coated quartz sand.  

PubMed

This paper intends to shed light on the interactions between tannin and mineral soil particles. For that purpose, aqueous solution of condensed tannin (CT) (derived from Black pine (Pinus nigra var. maritima)) and commercially available tannic acid (TA) were added to purified quartz (Qtz) sand and quartz sand coated with either goethite (Gt) or ferrihydrite (Fh). After solvent removal by evaporation the samples were extracted by water. The extracts were analysed for organic carbon, total phenolics and CT. The extractability of the two tannins was small and increased in the order Qtz-Fh < Qtz-Gt < Qtz. For all mineral samples, TA was more extractable than CT. Bonding of tannins to the mineral samples and the partial peptisation of the Fe oxide coatings upon the binding resulted in complex tannin release curves. Our results suggest that the inextractability of tannins from natural soils and the absence of tannins in soil leachates might be caused by strong adsorption on soil minerals such as Qtz and Fe (oxy)(hydr)oxides. The results of competition experiments with mixtures of both tannins demonstrate that the CTs, and TA in particular, can release large amounts of Fe (oxides), suggesting that the tannins are excellent metal-mobilising agents. We therefore suggest that the fate of tannins in the mineral soil environment is highly dependent on the abundance of weakly bonded secondary oxides. PMID:15914150

Kaal, J; Nierop, K G J; Verstraten, J M

2005-07-01

196

Synthesis of cyclopropyl glycosides and their use as novel glycosyl donors.  

PubMed

Methods for the synthesis of cyclopropyl glycosides and their use as glycosyl donors are described. Cyclopropyl glycosides containing different substituents were prepared by cyclopropanation of the corresponding vinyl glycosides, or by glycosidation of cyclopropyl alcohols that are synthesized by the Kulinkovich reaction. 1-Methyl- and 1-phenyl-substituted cyclopropyl glycosides undergo coupling to Fmoc-protected serine and threonine and to partially protected monosaccharides in the presence of TMS triflate to give glycosidated products. PMID:22475156

Scholl, Clark; Licisyn, Thomas; Cummings, Christopher; Hughes, Kevin; Johnson, David; Boyko, Walter; Giuliano, Robert

2012-07-15

197

Performance and characterization of a new tannin-based coagulant  

NASA Astrophysics Data System (ADS)

Diethanolamine and formaldehyde were employed to cationize tannins from black wattle. This novel coagulant called CDF was functionally characterized in removing sodium dodecylbenzene sulfonate (anionic surfactant) and Palatine Fast Black WAN (azoic dye). Refined tannin-derived commercial coagulants exhibited similar efficiency, while CDF presented higher coagulant ability than alum, a usual coagulant agent. Low doses of CDF (ca. 100 mg L-1) were able to remove more than 70 % of surfactant and more than 85 % of dye (initial pollutant concentration of ca. 100 mg L-1) and it presented no temperature affection and worked at a relatively wide pH range. Surfactant and dye removal responded to the classical coagulant-and-adsorption models, such as Frumkin-Fowler-Guggenheim or Gu and Zhu in the case of surfactant, and Langmuir and Freundlich in the case of dye.

Beltrán-Heredia, J.; Sánchez-Martín, J.; Gómez-Muñoz, C.

2012-09-01

198

Secondary-emission mass spectrometry of hederagenin glycosides and medicagenic acid glycosides  

Microsoft Academic Search

The secondary emission (SE) spectra of six glycosides of medicagenic acid (MA) and of hederagenin have been studied. The (M + H)+ ions were observed in the secondary ion spectra (LSIMS) of mono- and biosides of MA and also of a triand a tetraoside of hederagenin in a glycerol matrix. The (M + Na)+ ions were recorded in the spectra

Yu. M. Mil'grom; Ya. V. Rashkes; A. É. Timbekova

1992-01-01

199

Steroid saponins X. Glycosides of Allium narcissiflorum the structure of glycosides A and B  

Microsoft Academic Search

Summary  FromAllium narcissiflorum Wells have been isolated for the first time trillin and a glycoside B, which proved to be 3-O-[?-O-D-glucopyranosyl-(1 ? 3)-O-?-D-glucopyranosyl-(1 ? 6)-O-?-D-glucopyranosyl-(1 ?]-26-O-[?-D-glucopyranosyl-(1 ?]-25R-furost-5-ene-3?,22 ?, 26-triol.

V. V. Krokhmalyuk; P. K. Kintya

1976-01-01

200

Analysis of condensed and hydrolysable tannins from commercial plant extracts  

Microsoft Academic Search

High performance liquid chromatography (HPLC)\\/DAD and MS qualitative and quantitative analyses of polyphenols, hydrolysable and condensed tannins from Pinus maritima L. and tannic acid (TA) extracts were performed using normal and reverse phase.Normal-phase HPLC was more suitable for pine bark (PBE) and tannic acid extracts analysis. The chromatographic profile revealed that P. maritima L. extract was mainly composed by polymeric

A. Romani; F. Ieri; B. Turchetti; N. Mulinacci; F. F. Vincieri; P. Buzzini

2006-01-01

201

Identification of carcinogenic tannin isolated from Bracken fern (Pteridium aquilinum).  

PubMed

We attempted to isolate a carcinogenic substance from bracken fern (Pteridium aquilinum), a naturally occurring toxicant responsible for the production of chronic enzootic hematuria and urinary bladder cancer of cattle and carcinogenic for various target organs of several species. Hot methanol extracts of bracken fern were solubilized in water and extracted with chloroform followed by a mixture of n-butanol-butanone (1:1). That fraction was dried and triturated with ether-methanol (4:1), n-butanol, and finally absolute ethanol. The insoluble residue was dissolved in 10% aqueous methanol and passed through Dowex 1 OH-, Dowex 50 H+, or Dowex 1 OH- and then Dowex 50 H+ ion exchange resins. A condensed tannin, isolated from one ot the fractions, was identical to that isolated from bracken fern by the caffeine procedure used for the separation of tannins from other plant constituents. Three systems were used for bioassay; induction of bladder carcinoma by implantation of cholesterol pellets containing bracken fern fractions into the bladder lumens of mice; acute toxicity by ip injection of brachen fern fraction into mice; and growth inhibition of Escherichia coli. The following fractions induced significantly greater incidences of bladder carcinoma than did cholesterol pellets only: tannin, Dowex 50 H+, residue, n-butanol, and methanol. Tiliroside, a component of bracken fern fractions into the bladder lumens of mice; acute genic acid, and quercetin were not carcinogenic. Tannin was the most toxic (mean lethal dose: 0.16 mg/g) and carcinogenic. None of the carcinogenic fractions inhibited growth of E. coli. PMID:768500

Wang, C Y; Chiu, C W; Pamukcu, A M; Bryan, G T

1976-01-01

202

New phenanthrene glycosides from Dioscorea opposita.  

PubMed

Two new phenanthrene glycosides, dioscopposide A and dioscopposide B (1 and 2), were isolated from the rhizomes of Dioscorea opposita. Their structures were determined primarily on the basis of 1D and 2D NMR techniques, MS studies, and chemical methods. All the isolates were evaluated for their inhibitory effects on the lipopolysaccharide-induced nitric oxide production using murine macrophage RAW 264.7 cells. The IC50 values of dioscopposide A and dioscopposide B were 5.8 and 7.2 ?M, respectively. PMID:24168215

Zheng, Ken Yu-Zhong; Zhang, Zhen-Xia; Zhou, Wenliang; Cao, Hui; Xiang, Fei-Jun

2014-01-01

203

Glycosidic constituents from in vitro Anoectochilus formosanus.  

PubMed

The glycosidic constituents of whole plants of Anoectochilus formosanus propagated by tissue culture were investigated. A new compound, 2-(beta-D-glucopyranosyloxymethyl)-5-hydroxymethylfuran, along with the known compounds, 3-(R)-3-beta-D-glucopyranosyloxybutanolide (kinsenoside), 3-(R)-3-beta-D-glucopyranosyloxy-4-hydroxybutanoic acid, 1-O-isopropyl-beta-D-glucopyranoside, (R)-(+)-3,4-dihydroxy-butanoic acid y-lactone, 4-(beta-D-glucopyranosyloxy)benzyl alcohol, (6R,9S)-9-hydroxy-megastigma-4,7-dien-3-one-9-O-beta-glucopy ranoside, and corchoionoside C were isolated. PMID:11086921

Du, X M; Sun, N Y; Irino, N; Shoyama, Y

2000-11-01

204

Three new flavonoid glycosides from Urena lobata.  

PubMed

Three new flavonoid glycosides, kaempferol-3-O-?-D-apiofuranosyl(1 ? 2)-?-D-glucopyranosyl-7-O-?-L-rhamnopyranoside (1), kaempferol-4'-O-?-D-apiofuranosyl-3-O-?-D-glucopyranosyl-7-O-?-l-rhamnopyranoside (2), and 5,6,7,4'-tetrahydroxy-flavone-6-O-?-D-arabinopyranosyl-7-O-?-L-rhamnopyranoside (3), were isolated from the aerial parts of Urena lobata L., along with 10 known compounds (4-13). Their structures were determined based on spectroscopic methods including 1D and 2D NMR spectroscopy as well as HR-ESI-MS. PMID:21972805

Jia, Lu; A, You-Mei; Jing, Lin-Lin; Zhou, Sheng-An; Kong, De-Yun

2011-10-01

205

Fully acetylated carbamate and hypotensive thiocarbamate glycosides from Moringa oleifera  

Microsoft Academic Search

Six new and three synthetically known glycosides have been isolated from the leaves of Moringa oleifera, employing a bioassay-directed isolation method on the ethanolic extract. Most of these compounds, bearing thiocarbamate, carbamate or nitrile groups, are fully acetylated glycosides, which are very rare in nature. Elucidation of the structures was made using chemical and spectroscopic methods, including 2D NMR techniques.

Shaheen Faizi; Bina Shaheen Siddiqui; Rubeena Saleem; Salimuzzaman Siddiqui; Khalid Aftab; Anwar-Ul-Hassan Gilani

1995-01-01

206

Resveratrol/phloroglucinol glycosides from the roots of Lysidice rhodostegia.  

PubMed

Two new phloroglucinol glycosides, lysidisides C (1) and D (2), together with two new resveratrol glycosides, lysidisides E (3) and F (4), were isolated from the n-BuOH extract of the roots of Lysidice rhodostegia. The structures were elucidated on the basis of spectroscopic and chemical evidence. The antioxidant activity of the isolates was also investigated PMID:17415877

Gao, Song; Liu, Jing; Fu, Guang-Miao; Hu, You-Cai; Yu, Shi-Shan; Fan, Li-Hua; Yu, De-Quan; Qu, Jing

2007-02-01

207

Impact of condensed tannin size as individual and mixed polymers on bovine serum albumin precipitation.  

PubMed

Condensed tannins composed of epicatechin from monomer to octamer were isolated from cacao (Theobroma cacao, L.) seeds and added to bovine serum albumin (BSA) individually and combined as mixtures. When added to excess BSA the amount of tannin precipitated increased with tannin size. The amount of tannin required to precipitate BSA varied among the polymers with the trimer requiring the most to precipitate BSA (1000 ?g) and octamer the least (50 ?g). The efficacy of condensed tannins for protein precipitation increased with increased degree of polymerisation (or size) from trimers to octamers (monomers and dimers did not precipitate BSA), while mixtures of two sizes primarily had an additive effect. This study demonstrates that astringent perception is likely to increase with increasing polymer size. Further research to expand our understanding of astringent perception and its correlation with protein precipitation would benefit from sensory analysis of condensed tannins across a range of polymer sizes. PMID:24799203

Harbertson, James F; Kilmister, Rachel L; Kelm, Mark A; Downey, Mark O

2014-10-01

208

Pyrolysis-GC/MS of charred purified condensed tannin: towards identification of tannin-derived black carbon in environmental samples  

NASA Astrophysics Data System (ADS)

Tannins account for a significant proportion of plant biomass and are therefore a possible source of Black C in the charred remains from wildfires. Nonetheless, in contrast with other major biocomponents such as lignin and cellulose, the thermal degradation of tannins has not been investigated in laboratory charring experiments. We used pyrolysis-GC/MS to investigate the effects of furnace charring (30 min at fixed temperatures up to 600 °C under limited oxygen supply) on the degradation of pure condensed tannin (CT) isolated from Corsican pine (Pinus nigra) needles. The experiments showed a rapid loss (at 300 °C and higher) of the pyrogallol moieties of the B-ring of prodelphinidin-type CT, due to dehydroxylation. The relative abundance of catechols (from procyanidin-type CT) decreased at 350 °C and higher temperatures. This led to the formation of phenols that were strongly enriched between 300 and 400 °C. At higher temperatures, further dehydroxylation caused a decline in contributions of phenols producing a series of monocyclic aromatics ((alkyl)benzenes) and condensation of aromatics produced polycyclic aromatic hydrocarbons (PAHs), i.e. the typical pyrolysis fingerprint of strongly charred biomass. We conclude that (i) the thermal degradation of CT can be successfully monitored by pyrolysis-GC/MS, (ii) thermal degradation of CT is characterized by dehydroxylation of phenolic groups and condensation of aromatics that increase with temperature and (iii) CT-derived Black C may be recognized by catechol enrichments at low temperatures and possibly (relative) abundance of phenol and biphenyl at higher levels of thermal breakdown. Applying the same method to natural charcoal from gorse bushfires indicated that pyrolysis-GC/MS fingerprinting may allow for tannin identification in environmental Black C samples.

Kaal, Joeri; Nierop, Klaas G. J.; Kraal, Peter; Preston, Caroline M.

2010-05-01

209

The formulation and commercialization of glulam pine tannin adhesives in Chile  

Microsoft Academic Search

The results of fingerjointing and glulam industrial trials in Chile using a “honeymoon” fast-set adhesive system manufactured\\u000a using commercially-produced mildly-sulphited pine tannin extract are reported. The results obtained satisfy the relevant international\\u000a standards specifications and constitute the first occasion that a commercially produced pine tannin adhesive has been used\\u000a succesfully in industrial productions runs. This pine tannin adhesive is now

E. von Leyser; A. Pizzi

1990-01-01

210

Sensory properties of wine tannin fractions: implications for in-mouth sensory properties.  

PubMed

Different molecular structures of grape tannins have been shown to influence astringency, however, the in-mouth sensory effects of different molecular structures in red wine tannins remains to be established. The objective of this research was to assess the impact of wine tannin structure on in-mouth sensory properties. Wine tannin was isolated from Cabernet Sauvignon wines of two vintages (3 and 7 years old) and separated into two structurally distinct subfractions with liquid-liquid fractionation using butanol and water. The aqueous subfractions had greater mean degree of polymerization (mDp) and contained a higher proportion of epigallocatechin subunits than the butanol-soluble subfractions, while the older wine tannin fractions showed fewer epicatechin gallate subunits than the younger tannin fractions. The red wine had approximately 3:1 mass ratio of the aqueous and butanol tannin subfractions which approximated an equimolar ratio of tannin in each subfraction. Descriptive sensory analysis of the tannin subfractions in model wine at equimolar concentrations revealed that the larger, more water-soluble wine tannin subfractions from both wines were perceived as more astringent than the smaller, more hydrophobic and more highly pigmented butanol-soluble subfractions, which were perceived as hotter and more bitter. Partial least squares analysis indicated that the greater hydrophobicity and color incorporation in the butanol fractions was negatively associated with astringency, and these characteristics are also associated with aged wine tannins. As the larger, water-soluble tannins had a greater impact on the overall wine astringency, winemaking processes that modulate concentrations of these are likely to most significantly influence astringency. PMID:23289627

McRae, Jacqui M; Schulkin, Alex; Kassara, Stella; Holt, Helen E; Smith, Paul A

2013-01-23

211

Application of Mössbauer spectroscopy to the study of tannins inhibition of iron and steel corrosion  

NASA Astrophysics Data System (ADS)

The inhibitory effect of tannins was investigated using, among others, potentiodynamic polarizations and Mössbauer spectroscopy. These techniques confirmed that the nature, pH and concentration of tannic solution are of upmost importance in the inhibitory properties of the solutions. It is observed that at low tannin concentration or pH, both, hydrolizable and condensed tannins, effectively inhibit iron corrosion, due to the redox properties of tannins. At pH ? 0, Mössbauer spectra of the frozen aqueous solutions of iron(III) with the tannin solutions showed that iron is in the form of a monomeric species [Fe(H2O)6]3 + , without coordination with the functional hydroxyl groups of the tannins. The suspended material consisted of amorphous ferric oxide and oxyhydroxides, though with quebracho tannin partly resulted in complex formation and in an iron (II) species from a redox process. Other tannins, such as chestnut hydrolysable tannins, do not complex iron at this low pH. Tannins react at high concentrations or pH (3 and 5) to form insoluble blue-black amorphous complexes of mono-and bis-type tannate complexes, with a relative amount of the bis-ferric tannate generally increasing with pH. Some Fe2 + in the form of hydrated polymeric ferrous tannate could be obtained. At pH 7, a partially hydrolyzed ferric tannate complex was also formed. The latter two phases do not provide corrosion protection. Tannin solutions at natural pH react with electrodeposited iron films (approx. 6 ?m) to obtain products consisting only on the catecholate mono-complex of ferric tannate. Some aspects of the mechanism of tannins protection against corrosion are discussed.

Jaén, Juan A.; de Obaldía, J.; Rodríguez, M. V.

2011-11-01

212

Enhancing water repellence and mechanical properties of gelatin films by tannin addition  

Microsoft Academic Search

In order to reduce pollution caused by traditional non-biodegradable plastic films, renewable raw materials from plants and wastes of meat industries have been employed in this work. A hydrolysable chestnut-tree tannin was used for gelatin modification. Films of gelatin and gelatin–tannin were obtained by casting at room conditions. Transition temperatures of both gelatin and gelatin–tannin systems were determined by differential

Cristina Peña; Koro de la Caba; Arantxa Eceiza; Roxana Ruseckaite; Iñaki Mondragon

2010-01-01

213

Enzymatic synthesis of epothilone A glycosides.  

PubMed

Epothilones are extremely cytotoxic chemotherapeutic agents with epoxide, thiazole, and ketone groups that share equipotent kinetic similarity with taxol. The in vitro glycosylation catalyzed by uridine diphosphate glucosyltransferase (YjiC) from Bacillus licheniformis generated six novel epothilone A glycoside analouges including epothilone A 7-O-?-D-glucoside, epothilone A 7-O-?-D-galactoside, epothilone A 3,7-O-?-D-digalactoside, epothilone A 7-O-?-D-2-deoxyglucoside, epothilone A 7-O-?-L-rhamnoside, and epothilone A 7-O-?-L-fucoside. Epothilone A 7-O-?-D-glucoside was structurally elucidated by ultra-high performance liquid chromatography-photo diode array (UPLC-PDA) conjugated with high resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS) supported by one-and two-dimensional nuclear magnetic resonance studies whereas other epothilone A glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The time dependent conversion study of epothilone A to epothilone A 7-O-?-D-glucoside found to be maximum (~26%) between 3 h to 5 h incubation. PMID:24949266

Parajuli, Prakash; Pandey, Ramesh Prasad; Koirala, Niranjan; Yoon, Yeo Joon; Kim, Byung-Gee; Sohng, Jae Kyung

2014-01-01

214

Enzymatic synthesis of epothilone A glycosides  

PubMed Central

Epothilones are extremely cytotoxic chemotherapeutic agents with epoxide, thiazole, and ketone groups that share equipotent kinetic similarity with taxol. The in vitro glycosylation catalyzed by uridine diphosphate glucosyltransferase (YjiC) from Bacillus licheniformis generated six novel epothilone A glycoside analouges including epothilone A 7-O-?-D-glucoside, epothilone A 7-O-?-D-galactoside, epothilone A 3,7-O-?-D-digalactoside, epothilone A 7-O-?-D-2-deoxyglucoside, epothilone A 7-O-?-L-rhamnoside, and epothilone A 7-O-?-L-fucoside. Epothilone A 7-O-?-D-glucoside was structurally elucidated by ultra-high performance liquid chromatography-photo diode array (UPLC-PDA) conjugated with high resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS) supported by one-and two-dimensional nuclear magnetic resonance studies whereas other epothilone A glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The time dependent conversion study of epothilone A to epothilone A 7-O-?-D-glucoside found to be maximum (~26%) between 3 h to 5 h incubation.

2014-01-01

215

Condensed Tannins from Ficus virens as Tyrosinase Inhibitors: Structure, Inhibitory Activity and Molecular Mechanism  

PubMed Central

Condensed tannins from Ficus virens leaves, fruit, and stem bark were isolated and their structures characterized by 13C nuclear magnetic resonance spectrometry, high performance liquid chromatography electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The results showed that the leaves, fruit, and stem bark condensed tannins were complex mixtures of homo- and heteropolymers of B-type procyanidins and prodelphinidins with degrees of polymerization up to hexamer, dodecamer, and pentadecamer, respectively. Antityrosinase activities of the condensed tannins were studied. The results indicated that the condensed tannins were potent tyrosinase inhibitors. The concentrations for the leaves, fruit, and stem bark condensed tannins leading to 50% enzyme activity were determined to be 131.67, 99.89, and 106.22 ?g/ml on monophenolase activity, and 128.42, 43.07, and 74.27 ?g/ml on diphenolase activity. The inhibition mechanism, type, and constants of the condensed tannins on the diphenolase activity were further investigated. The results indicated that the condensed tannins were reversible and mixed type inhibitors. Fluorescence quenching, copper interacting, and molecular docking techniques were utilized to unravel the molecular mechanisms of the inhibition. The results showed that the hydroxyl group on the B ring of the condensed tannins could chelate the dicopper irons of the enzyme. Moreover, the condensed tannins could reduce the enzyme product o-quinones into colourless compounds. These results would contribute to the development and design of antityrosinase agents.

Chai, Wei-Ming; Feng, Hui-Ling; Zhuang, Jiang-Xing; Chen, Qing-Xi

2014-01-01

216

Analysis of phytochemical constituents of Eucalyptus citriodora L. responsible for antifungal activity against post-harvest fungi  

Microsoft Academic Search

In vitro antifungal activity and phytochemical constituents of essential oil, aqueous, methanol and chloroform extract of Eucalyptus citriodora Hook leaves were investigated. A qualitative phytochemical analysis was performed for the detection of alkaloids, cardiac glycosides, flavonoids, saponins, sterols, tannins and phenols. Methanolic extract holds all identified biochemical constituents except for the tannin. While these biochemical constituents were found to be absent

S. Javed; A. Shoaib; Z. Mahmood; S. Mushtaq; S. Iftikhar

2012-01-01

217

Analysis of phytochemical constituents of Eucalyptus citriodora L. responsible for antifungal activity against post-harvest fungi  

Microsoft Academic Search

In vitro antifungal activity and phytochemical constituents of essential oil, aqueous, methanol and chloroform extract of Eucalyptus citriodora Hook leaves were investigated. A qualitative phytochemical analysis was performed for the detection of alkaloids, cardiac glycosides, flavonoids, saponins, sterols, tannins and phenols. Methanolic extract holds all identified biochemical constituents except for the tannin. While these biochemical constituents were found to be absent

S. Javed; A. Shoaib; Z. Mahmood; S. Mushtaq; S. Iftikhar

2011-01-01

218

Determination of bioactive nitrile glycoside(s) in drumstick ( Moringa oleifera) by reverse phase HPLC  

Microsoft Academic Search

A high-performance liquid chromatographic method for the determination of novel bioactive nitrile glycosides niaziridin and niazirin in the leaves, pods and bark of Moringa oleifera is reported. Niaziridin is a bioenhancer for drugs and nutrients. The analytical conditions for reversed-phase HPLC with UV detection were as follows: column, Chromolith RP-18e, 4.6×100mm 0.5?m (Merck); column temperature, 25°C; mobile phase, a 20:80

Karuna Shanker; Madan M. Gupta; Santosh K. Srivastava; Dnyaneshwar U. Bawankule; Anirban Pal; Suman P. S. Khanuja

2007-01-01

219

[Membranotropic effect of some triterpene glycosides possessing immunostimulating properties].  

PubMed

The peculiarities of the interaction between cell membrane lipids and triterpene glycosides from holothurians Apostichopus japonicus S. and Cucumaria japonica (holotoxin A1 and cucumarioside A2-2, respectively) were studied in comparison with plant saponins from Quillaja saponaria, known as hemolytic, adjuvant, and structure-forming components of immunostimulating complexes. Similar to Quillaja saponins, the sea glycosides, holotoxin A1 and cucumarioside A2-2 were shown to possess a high hemolytic activity (2.6 and 3 microg/ml, respectively) and sterol-depending membranotropic effect mediated by the formation of nonbilayer sterol-lipid-glycoside complexes. At the same time, cucumarioside A2-2 bound exogenic cholesterol only in the presence of membrane lipids, such as phosphatidylcholine or monogalactosyldiacylglycerol, in contrast to Quillaja saponins and holotoxin A1, which bound cholesterol in the molar ratios 1:2 and 1:8, respectively. Moreover, in all cases, tree-component complexes containing cholesterol, lipid, and glycoside exhibited a lower hemolytic activity compared with two-component sterol-glycoside complexes. It was concluded that the hydrophobic medium of cell membranes performs a potentiative role in the effective interaction between triterpene glycosides and "sterol receptors". A method for decreasing the toxicity of membranotropic holothurian glycosides possessing the immunomodulating properties was suggested. PMID:18634319

Lee, I A; Popov, A M; Kostetski?, E Ia; Sanina, N M; Maze?ka, A N; Boguslavski?, V M

2008-01-01

220

About Cardiac Arrest  

MedlinePLUS

... High Blood Pressure Tools & Resources Stroke More About Cardiac Arrest Updated:Nov 25,2013 What is cardiac arrest? ... content was last reviewed on 02/26/2013. Cardiac Arrest • Home • About Cardiac Arrest • Warning Signs for Cardiac ...

221

Sodium-potassium movement and the regulation of cardiac muscle activity.  

PubMed

The changes in intracellular sodium activity and contractility produced by short-lasting application of a fast-acting cardiac glycoside were measured in guinea-pig ventricular muscle. It was found that under certain conditions the change in twitch tension paralleled the change in sodium activity. It is suggested that the electrogenic sodium pump may be involved in the regulation of both the mechanical and the electrical activity of cardiac muscle. PMID:7136181

Daut, J; Rüdel, R

1982-01-01

222

New iridoid glycoside from Gratiola officinalis.  

PubMed

A new iridoid glycoside, 1?,6?-di-O-trans-cinnamoyl-9-O-?-D-glucopyranosyl-3-iridene-5?-ol (1), along with four known compounds loliolide (2), ?-sitosterol-3-O-?-D-glucopyranoside (3), betulinic acid (4), and ?-amyrin (5), was isolated from the aerial parts of Gratiola officinalis L. The structure of the new compound was deduced on the basis of 1D ¹H and ¹³C NMR and 2D HMQC, HMBC, and COSY experiments, and mass spectrometric techniques (EI-MS and HR-EI-MS). The relative configuration of 1 was assigned by comparative analysis of the NMR spectral data with known analogs, together with NOESY experiments. PMID:23134347

Ali, Liaqat; Rizvi, Tania Shamim; Ahmad, Manzoor; Shaheen, Farzana

2012-01-01

223

New steroidal glycosides from Tribulus terrestris L.  

PubMed

Two new steroidal glycosides were isolated from Tribulus terrestris L. Their structures were elucidated as 26-O-?-D-glucopyranosyl-5?-furostan-12-one-20(22)-ene-3?,23,26-triol-3-O-?-D-xylopyranosyl-(1 ? 2)-[?-D-xylopyranosyl-(1 ? 3)]-?-D-glucopyranosyl-(1 ? 4)-[?-L-rhamnopyranosyl-(1 ? 2)]-?-D-galactopyranoside (1) and 26-O-?-D-glucopyranosyl-5?-furostan-20(22)-ene-3?,23,26-triol-3-O-?-D-xylopyranosyl-(1 ? 2)-[?-D-xylopyranosyl-(1 ? 3)]-?-D-glucopyranosyl-(1 ? 4)-[?-L-rhamnopyranosyl-(1 ? 2)]-?-D-galactopyranoside (2) by spectroscopic methods including 1D and 2D NMR experiments. PMID:22694659

Chen, Gang; Liu, Tao; Lu, Xuan; Wang, Hai-Feng; Hua, Hui-Ming; Pei, Yue-Hu

2012-01-01

224

Cytotoxic steroidal glycosides from Allium flavum.  

PubMed

Three new spirostane-type glycosides (1-3) were isolated from the whole plant of Allium flavum. Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as (20S,25R)-2?-hydroxyspirost-5-en-3?-yl O-?-D-xylopyranosyl-(1?3)-[?-D-galactopyranosyl-(1?2)]-?-D-galactopyranosyl-(1?4)-?-D-galactopyranoside (1), (20S,25R)-2?-hydroxyspirost-5-en-3?-yl O-?-D-xylopyranosyl-(1?3)-[?-D-glucopyranosyl-(1?2)]-?-D-galactopyranosyl-(1?4)-?-D-galactopyranoside (2), and (20S,25R)-spirost-5-en-3?-yl O-?-L-rhamnopyranosyl-(1?4)-[?-D-glucopyranosyl-(1?2)]-?-D-glucopyranoside (3). The three saponins were evaluated for cytotoxicity against a human cancer cell line (colorectal SW480). PMID:24380693

Rezgui, Abdelmalek; Mitaine-Offer, Anne-Claire; Paululat, Thomas; Delemasure, Stéphanie; Dutartre, Patrick; Lacaille-Dubois, Marie-Aleth

2014-03-01

225

Phenolic glycosides from Symplocos racemosa: natural inhibitors of phosphodiesterase I.  

PubMed

One new phenolic glycoside named benzoylsalireposide (1) along with one known phenolic glycoside named salireposide (2) have been isolated from Symplocos racemosa. Four other known compounds i.e. beta-amyrin (3), oleonolic acid (4), beta-sitosterol (5) and beta-sitosterol glycoside (6) were also isolated from this plant. The structure elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR analysis, including COSY, HMQC, and HMBC correlations. The compound 1 and 2 showed inhibitory activity against snake venom phosphodiesterase I. PMID:12711144

Ahmad, Viqar Uddin; Abbasi, Muhammad Athar; Hussain, Hidayat; Akhtar, Muhammad Nadeem; Farooq, Umar; Fatima, Naheed; Choudhary, M Iqbal

2003-05-01

226

Synthesis and sensory evaluation of ent-kaurane diterpene glycosides.  

PubMed

Catalytic hydrogenation of the three ent-kaurane diterpene glycosides isolated from Stevia rebaudiana, namely rubusoside, stevioside, and rebaudioside-A has been carried out using Pd(OH)? and their corresponding dihydro derivatives have been isolated as the products. Synthesis of reduced steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR spectral data and chemical studies. Also, we report herewith the sensory evaluation of all the reduced compounds against their corresponding original steviol glycosides and sucrose for the sweetness property of these molecules. PMID:22836210

Prakash, Indra; Campbell, Mary; San Miguel, Rafael Ignacio; Chaturvedula, Venkata Sai Prakash

2012-01-01

227

Steroidal glycosides from the bulbs of Ornithogalum thyrsoides.  

PubMed

Phytochemical analyses have been carried out on the fresh bulbs of Ornithogalum thyrsoides with particular attention to the steroidal glycoside constituents, resulting in the isolation of four new spirostanol saponins and seven new cholestane glycosides, together with three known steroidal compounds. The structures of the new glycosides were determined on the basis of their spectroscopic data, including 2D NMR spectroscopy, and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activities against HL-60 human promyelocytic leukemia cells and HSC-2 human oral squamous cell carcinoma cells. PMID:15497941

Kuroda, Minpei; Mimaki, Yoshihiro; Ori, Kazutomo; Sakagami, Hiroshi; Sashida, Yutaka

2004-10-01

228

Triterpene saponins of Caltha polypetala. Glycosides G and I  

Microsoft Academic Search

From the epigeal organs of the great march marigold (family Ranunculaceae) two triterpene glycosides, a tetra- and a pentaoside of hederagenin, have been isolated. Their chemical structures have been established by chemical methods of investigation and by1H and13C NMR spectroscopy. Glycoside G is hederagenin 3-O-a-L-arabinoside 28-O-[O-a-L-rhamnopyranosyl-(1 ? 4)-O-ß-D-glucopyranosyl-(1 ? 6)-ß-D-glucopyranoside]. Glycoside I is hederagenin 3-O-[O-ß-D-glucopyranosyl-(1 ? 2)-a-L-arabinoside 28-O-[O-a-L-rhamnopyranosyl-(1 ? 4)-O-ß-D-glucopyranosyl-(1

M. M. Vugalter; G. E. Dekanosidze; O. D. Dzhikiya; A. S. Shashkov; É. P. Kemertelidze

1988-01-01

229

Lignan, phenolic and iridoid glycosides from Stereospermum cylindricum.  

PubMed

A lignan glycoside [(+)-cycloolivil 4'-O-beta-d-glucopyranoside], a phenolic glycoside [3,4-dimethoxyphenyl 1-O-beta-d-xylopyranosyl-(1-->6)-beta-d-glucopyranoside] and a iridoid glycoside (stereospermoside) were isolated from the leaves and branches of Stereospermum cylindricum, together with (+)-cycloolivil, (+)-cycloolivil 6-O-beta-d-glucopyranoside, (-)-olivil, (-)-olivil 4-O-beta-d-glucopyranoside, (-)-olivil 4'-O-beta-d-glucopyranoside, vanilloloside, decaffeoyl-verbascoside, isoverbascoside, 3,4,5-trimethoxyphenyl 1-O-beta-d-xylopyranosyl-(1-->6)-beta-d-glucopyranoside, ajugol, verminoside, and specioside. The structure elucidations were based on spectroscopic evidence. PMID:16310232

Kanchanapoom, Tripetch; Noiarsa, Pawadee; Otsuka, Hideaki; Ruchirawat, Somsak

2006-03-01

230

Amelioration of doxorubicin-induced cardiac and renal toxicity by pirfenidone in rats  

Microsoft Academic Search

Purpose Doxorubicin (DXR) is an anthracycline glycoside with a broad spectrum of therapeutic activity against various tumors. However, the clinical use of DXR has been limited by its undesirable systemic toxicity, especially in the heart and kidney. This study was designed to test the effectiveness of dietary intake of pirfenidone (PD) against DXR-induced cardiac and renal toxicity. Methods Male Sprague

Shri N. Giri; MohammedAli Al-Bayati; Xiaogu Du; Edward Schelegle; F. Charles Mohr; Solomon B. Margolin

2004-01-01

231

The effect of some tannins on trout erythrocytes exposed to oxidative stress  

Microsoft Academic Search

In order to gain more knowledge on the role of tannins as antioxidants, their ability to protect (Salmo irideus) erythrocytes against oxidative stress was investigated. Antioxidant activity of different tannins (tannic, gallic and ellagic acid) was evaluated by chemiluminescence (CL) techniques using lucigenin and luminol as chemiluminogenic probes for the superoxide radical generated by the xanthine\\/xanthine oxidase system and hydrogen

Donatella Fedeli; Marco Berrettini; Teresa Gabryelak; Giancarlo Falcioni

2004-01-01

232

A critical analysis of techniques for measuring tannins in ecological studies  

Microsoft Academic Search

A series of seventeen plant extracts rich in phenolic materials, including condensed and hydrolysable tannins, have been subjected to a series of chemical analyses in an attempt to gather ecologically significant information about their structure. Procedures investigated were (i) the Folin-Denis and Hagerman and Butler methods for quantifying total phenolics, (ii) the vanillin and proanthocyanidin methods for quantifying condensed tannins,

S. Mole; P. G. Waterman

1987-01-01

233

Isolation and purification of condensed tannins from flamboyant tree and their antioxidant and antityrosinase activities.  

PubMed

Flamboyant tree, a kind of medicinal plant, was studied as a source of condensed tannins. The antioxidant activities of the condensed tannins from the leaf, fruit, and stem bark of flamboyant tree were screened by ABTS radical and hydroxyl radical scavenging activity methods. The results indicated that these compounds possessed potent antioxidant activity. Their structures were then characterized by high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) after thiolytic degradation. The results showed that the leaf condensed tannins were composed of afzelechin/epiafzelechin, catechin/epicatechin, and gallocatechin/epigallocatechin, while the fruit and stem bark condensed tannins had afzelechin/epiafzelechin and catechin/epicatechin. In addition, the condensed tannins were evaluated for their antityrosinase ability. They were found to have significant antityrosinase activity. The IC50 values were 35 ± 2.0 and 40 ± 0.5 ?g/ml for the condensed tannins of fruit and stem bark, respectively. Further, fluorescence quenching and copper interacting techniques were utilized to unravel the molecular mechanisms of the inhibition. The results showed that the hydroxyl group of the condensed tannins could chelate the dicopper center of the enzyme and interact with tryptophan residues. Our studies revealed that condensed tannins might be suitable for use in food, agriculture, cosmetic, nutraceutical, and pharmaceutical applications. PMID:24671565

Feng, Hui-Ling; Tian, Ling; Chai, Wei-Ming; Chen, Xiao-Xin; Shi, Yan; Gao, Yu-Sen; Yan, Chong-Ling; Chen, Qing-Xi

2014-05-01

234

Insect grazing on Eucalyptus in response to variation in leaf tannins and nitrogen  

Microsoft Academic Search

Many species of Eucalyptus, one of the dominant genera in Australian forests and woodlands, contain high levels of tannins and other phenols and are also heavily damaged by grazing insects. These phenols do not appear to affect insect attack because a wide range of concentrations of condensed tannins and other phenols in leaves of 13 Eucalyptus sp. influenced neither feeding

Laurel R. Fox; B. J. Macauley

1977-01-01

235

Effects of Condensed Tannins on Endoglucanase Activity and Filter Paper Digestion by Fibrobacter succinogenes S85 †  

PubMed Central

The effect of condensed tannins from birdsfoot trefoil (Lotus corniculatus L.) on the cellulolytic rumen bacterium Fibrobacter succinogenes S85 was examined. Condensed tannins inhibited endoglucanase activity in the extracellular culture fluid, at concentrations as low as 25 ?g ml-1. In contrast, cell-associated endoglucanase activity increased in concentrations of condensed tannins between 100 and 300 ?g ml-1. Inhibition of endoglucanase activity in both the extracellular and the cell-associated fractions was virtually complete at 400 ?g of condensed tannins ml-1. Despite the sharp decline in extracellular endoglucanase activity with increasing concentrations of condensed tannins, filter paper digestion declined only moderately between 0 and 200 ?g of condensed tannins ml-1. However, at 300 ?g ml-1, filter paper digestion was dramatically reduced and at 400 ?g ml-1, almost no filter paper was digested. F. succinogenes S85 was seen to form digestive grooves on the surface of cellulose, and at 200 ?g ml-1, digestive pits were formed which penetrated into the interior of cellulose fibers. Cells grown with condensed tannins (100 to 300 ?g ml-1) possessed large amounts of surface material, and although this material may have been capsular carbohydrate, its osmiophilic nature suggested that it had arisen from the formation of tannin-protein complexes on the cell surface. The presence of electron-dense extracellular material suggested that similar complexes were formed with extracellular protein. Images

Bae, Hee Dong; McAllister, Tim A.; Yanke, Jay; Cheng, K.-J.; Muir, A. D.

1993-01-01

236

Research observation: Hydrolyzable and condensed tannins in plants of northwest Spain forests  

USGS Publications Warehouse

Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, E. E.

2003-01-01

237

Distribution and concentration of total phenolics, condensed tannins, and nordihydroguaiaretic acid (NDGA) in creosotebush ( Larrea tridentata)  

Microsoft Academic Search

This paper focuses on the presence and distribution of secondary phenolic compounds found within creosotebush [Larrea tridentata (Sess. & Moc. ex DC.) Cov.]. Total phenolics, condensed tannins and nordihydroguaiaretic acid (NDGA) were measured in nine categories of tissue within creosotebush. Total phenolic and condensed tannin concentrations were determined using colorimetric methods while NDGA content was determined with high performance liquid

Paul W. Hyder; E. L. Fredrickson; Rick E. Estell; Mario Tellez; Robert P. Gibbens

2002-01-01

238

[Separation of tannins in Rhubarb and its analysis by high performance liquid chromatography-mass spectrometry].  

PubMed

In order to investigate the pharmaceutical actions of rhubarb, a method for extracting, separating and analyzing the tannin components in rhubarb was studied. At first, a procedure for the group separation of tannins from the water-ethanol extract of rhubarb was established based on the formation of tannins-caffein precipitation. Then, a high performance liquid chromatographic (HPLC) method for the analysis of tannins in rhubarb was developed. This HPLC method is based on a reversed-phase C18 column and polar mobile-phase such as water and methanol with gradient elution, and the tannins can be well separated. Finally, the identification of the tannin components in rhubarb was carried out by high performance liquid chromatography-mass spectrometry (HPLC-MS). The structures of the main tannin components (gallic acid, catechin, the dimer, trimer, tetramer and pentamer of catechin) in rhubarb are suggested. The fragmentation laws of the tannin components are summarized. In comparing with previous methods, it is simple and without the interference of co-existed compounds. PMID:15807111

Ding, Mingyu; Ni, Weiwei

2004-11-01

239

Research observation: Hydrolyzable and condensed tannins in plants of the northwest  

USGS Publications Warehouse

Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, Edward E.

2003-01-01

240

Condensed tannins deter feeding by browsing ruminants in a South African savanna  

Microsoft Academic Search

The palatability of 14 species of woody plant was assessed for three species of browsing ruminant, namely kudus, impalas and goats. Results show that palatability was most clearly related to leaf contents of condensed tannins. The effect was a threshold one, with all plants containing more than 5% condensed tannins being rejected as food during the wet season period. In

S. M. Cooper; N. Owen-Smith

1985-01-01

241

Modification of grape seed and wood tannins to lipophilic antioxidant derivatives  

Microsoft Academic Search

We made lipophilic plant tannins by grafting on them alkyl chains through friendly and cheap chemical modifications. For that purpose, some reactions were applied to tannins from wood (chestnut, oak and quebracho) and from grape seed: esterification by a fatty acid and oxa-Pictet–Spengler coupling. The latter was carried out with variable length methylketones in very mild and simple conditions. After

Bouddah Poaty; Stéphane Dumarçay; Philippe Gérardin; Dominique Perrin

2010-01-01

242

Characterization of Tannin Acylhydrolase Activity in the Ruminal Bacterium Selenomonas Ruminantium  

Microsoft Academic Search

A strain of the anaerobe Selenomonas ruminantium subsp. ruminantium that is capable of growing on tannic acid or condensed tannin as a sole energy source has been isolated from ruminal contents of feral goats browsing tannin-rich Acacia sp. Growth on tannic acid was accompanied by release of gallic acid into the culture medium but the bacterium was incapable of using

I. K. Skene; J. D. Brooker

1995-01-01

243

Polyflavonoid tannins — a main cause of soft-rot failure in CCA-treated timber  

Microsoft Academic Search

Polyflavonoid tannins are proven to be fast-reacting with CCA solutions and hence, to be strong competitors of the structural wood constituents for fixation of CCA preservatives. The consequence of this effect is that even relatively small amounts of tannin cause severe undertreatment of the structural wood constituents which in turn badly affects the long term durability of CCA treated timber.

A. Pizzi; A. Jansen

1986-01-01

244

Adams-Harbertson Protein Precipitation-Based Wine Tannin Method Found Invalid  

Microsoft Academic Search

The poor precision of the Adams-Harbertson wine tannin assay which was proposed for commercial winemaking, thereby creating the real possibility of quality control problems, is documented. The method is a version of the Hagerman and Butler protein precipitation-based tannin method. An extensive invalidation of the assay results with luxury wine data shows that the assay cannot distinguish bottled wine with

LARRY BROOKS

245

Characterization of Acacia mangium polyflavonoid tannins by MALDI-TOF mass spectrometry and CP-MAS 13C NMR  

Microsoft Academic Search

The MALDI-TOF mass spectrometry (MS) and solid state CP-MAS 13C Nuclear Magnetic Resonance (NMR) spectroscopic technique were introduced to characterize Acacia mangium tannin (condensed tannins). The MALDI-TOF MS illustrated a series of peaks corresponding to oligomers of condensed tannins of up to 11 flavonoid units (3200Da). A. mangium condensed tannins were found to consist predominantly of prorobinetinidin combined with profisetinidin

Yeoh Beng Hoong; Antonio Pizzi; Harald Pasch

2010-01-01

246

The antimicrobial activities of methanolic extracts of Eucalyptus camaldulensis and Terminalia catappa against some pathogenic microorganisms  

Microsoft Academic Search

Methanolic extracts of leaves of Eucalyptus camaldulensis and Terminalia catappa were studied for in vitro microbial activities by agar dilution method. The phytochemical analysis of the crude extracts of the medicinal plants revealed the presence of saponin, saponin glycosides, steroid, cardiac glycoside, tannins, volatile oils, phenols and balsam (gum). The methanolic extracts of the two plants inhibited the growth of

H. Babayi; I. Kolo; J. I. Okogun; U. J. J. Ijah

2004-01-01

247

Pre-fermentation addition of grape tannin increases the varietal thiols content in wine.  

PubMed

The recent finding that grape tannin may contain significant amount of S-glutathionylated (GSH-3MH) and S-cysteinylated (Cys-3MH) precursors of the varietal thiols 3-mercapto-1-hexanol and 3-mercaptohexyl acetate, characteristic of Sauvignon blanc wines, offers new opportunities for enhancing the tropical aroma in fermented beverages. In this study this new hypothesis was investigated: Müller Thurgau (17 samples) and Sauvignon blanc (15 samples) grapes were fermented with and without addition of a selected grape tannin. As expected, the tannin-added juices were higher in precursors, and they produced wines with increased free thiols. Preliminary informal sensory tests confirmed that in particular the Sauvignon wines produced with the tannin addition were often richer with increased "fruity/green" notes than the corresponding reference wines. This outcome confirms that grape tannin addition prior to fermentation can fortify the level of these compounds. PMID:25053028

Larcher, Roberto; Tonidandel, Loris; Román Villegas, Tomás; Nardin, Tiziana; Fedrizzi, Bruno; Nicolini, Giorgio

2015-01-01

248

Eco-dyeing using Tamarindus indica L. seed coat tannin as a natural mordant for textiles with antibacterial activity  

Microsoft Academic Search

Tamarind seed coat tannin was extracted and its tannin class was determined. The extracted tannin was employed as a natural mordant alone and in combination with metal mordant namely copper sulphate for cotton, wool and silk fabrics and dyed using natural dyes namely turmeric and pomegranate rind. The colour strength, colour coordinates, wash and light fastness were evaluated and compared

K. H. Prabhu; M. D. Teli

249

A new phenolic glycoside from the roots of Lygodium japonicum  

Microsoft Academic Search

A new phenolic glycoside, 3,4-dihydroxybenzoic acid 4-O-(4?-O-methyl)-?-D-glucopyranoside (1), was isolated from the roots of Lygodium japonicum. The structure was elucidated on the basis of spectroscopic methods.

Wencai Ye; Chunlin Fan; Leihong Zhang; Zhiqi Yin; Shouxun Zhao

2007-01-01

250

A new phenolic glycoside from the roots of Lygodium japonicum.  

PubMed

A new phenolic glycoside, 3,4-dihydroxybenzoic acid 4-O-(4'-O-methyl)-beta-D-glucopyranoside (1), was isolated from the roots of Lygodium japonicum. The structure was elucidated on the basis of spectroscopic methods. PMID:17570612

Ye, Wencai; Fan, Chunlin; Zhang, Leihong; Yin, Zhiqi; Zhao, Shouxun

2007-12-01

251

Steroid saponins III. Glycosides A and B from Yucca filamentosa  

Microsoft Academic Search

Summary  Two glycosides have been isolated from the roots ofYucca filamentosa L. One of them proved to be trillin, and the second — yuccoside B — 3-O-[galactopyranosyl-1(1 ? 4)-glucopyranosyl]tigogenin.

P. K. Kintya; I. P. Dragalin; V. Ya. Chirva

1972-01-01

252

3-hydroxycoumarin glycosides from Alyxia reinwardti var. Lucida.  

PubMed

Investigation of the inner bark of Alyxia reinwardti var. lucida led to the isolation of two new coumarin glycosides, 1 and 2, whose structures were determined by interpretation of their spectroscopic data, particularly NMR spectroscopy. PMID:7764154

Lin, L J; Lin, L Z; Ruangrungsi, N; Cordell, G A

1993-10-01

253

Rebaudioside F, a diterpene glycoside from Stevia rebaudiana  

Microsoft Academic Search

The sweet diterpenoid glycoside, rebaudioside F, was isolated from leaves of a high rebaudioside C producing line of Stevia rebaudiana, and its structure was established by chemical and spectral studies.

Alvin N. Starratt; Christopher W. Kirby; Robert Pocs; James E. Brandle

2002-01-01

254

Mechanism of hexavalent chromium adsorption by persimmon tannin gel.  

PubMed

Mechanism of chromium adsorption by the persimmon tannin (PT) gel was examined. The PT gel can adsorb Cr highly effectively from aqueous solutions containing Cr(VI), while it adsorbed far smaller amounts of Cr from the solution containing Cr(III). The maximum Cr adsorption from the Cr(VI) solution occurred at pH 3. The Cr adsorption from the Cr(VI) solution by the PT gel was rapid, was faster than VO2+ and Fe3+ adsorptions, and was obeyed the Langmuir adsorption isotherm (Qe= 5.27 mmol g(-1) and K= 16.2 mM). The gel adsorbed Cr from the Cr(VI) solution (pH 1 and 3) showed no ESR signal of Cr(III), while the ESR signal of Cr(III) was observed in the residual solution at pH 1. Hexavalent chromium was, therefore, adsorbed on the PT gel through the esterification of chromate with catechol group. In other words, Cr(VI) should combine with catechol as a hard acid, CrO2(2+) cation. Through the treatment of a Cr(VI) solution with the PT gel, chromium should be recovered as a Cr(IV)-tannin complex at pH 3 or a Cr(III) solution at pH 1 or lower pH region. PMID:15223280

Nakajima, Akira; Baba, Yoshinari

2004-07-01

255

Saliva of the graminivorous Theropithecus gelada lacks proline-rich proteins and tannin-binding capacity.  

PubMed

Gelada baboons are the sole survivors of the genus Theropithecus and the only known graminivorous primates. They developed special adaptations to their diet such as high-crowned teeth for processing hard and abrasive feed. The fine-tuning of salivary protein composition might be another key mechanism that is used by species for adapting to the environment and competing with rivals for exploiting new ecological niches. In order to test whether gelada (graminivorous) and hamadryas baboons (omnivorous) differ in their salivary protein composition, we compared whole saliva samples of captive Theropithecus gelada and Papio hamadryas using gel electrophoresis and tannin-binding assay. We hypothesized that the amount of proline-rich salivary proteins with tannin-binding capacity is higher in baboons consuming a feed with high dicot/monocot rations. Dicots produce tannins as a chemical defense system, discouraging animals from eating them. In contrast to dicots, monocots do not synthesize tannins. The presence of tannin-binding proteins in saliva should effectively inactivate the dicot tannin-based defense mechanism and increase the dietary breadth and/or the capability to switch between monocots and dicot leaves. The lack of such tannin-binding proteins in saliva would indicate a narrow dietary spectrum more restricted to monocots. We found T. gelada to completely lack proline-rich proteins (PRPs) and tannin-binding capacity similar to a great variety of other grazing mammals. In contrast, P. hamadryas does possess PRPs with tannin-binding activity. The findings support a growing body of evidence suggesting a high-level specialization of T. gelada to grass diets. However, it remains unclear, whether loss of salivary tannin-binding capacity drove the gelada into its narrow feeding niche, or whether this loss is the result of a long process of increased specialization. Thus, from an ecological point of view, T. gelada appears to be more vulnerable to environmental changes than other baboon species owing to its narrow dietary traits. PMID:19431194

Mau, Marcus; Südekum, Karl-Heinz; Johann, Achim; Sliwa, Alexander; Kaiser, Thomas M

2009-08-01

256

Cardiac rhabdomyosarcoma.  

PubMed

Cardiac sarcoma is a very rare neoplasm and is difficult to diagnose. The case of a 51-year-old man with a left atrial tumour, locally recurrent three months after its surgical removal, is presented. Computed tomography showed metastatic spread to the lung parenchyma. On revised histology, the mass extirpated was a sarcoma. Because of the metastatic spread, further therapy was symptomatic only; the patient died 15 months after the first manifestation of his problems. Immunohistochemical staining confirmed cardiac rhabdomyosarcoma with metastatic spread to the lungs. Difficulty in diagnosing and treating cardiac tumours is discussed. PMID:20428274

Chlumský, J; Holá, D; Hlavácek, K; Michal, M; Svec, A; Spatenka, J; Dusek, J

2001-01-01

257

Glycosides of benzyl and salicyl alcohols from Alangium chinense.  

PubMed

From the water-soluble fraction of the dried leaves of Alangium chinense, three new glycosides, benzyl alcohol beta-D-glucopyranosyl-(1 --> 2)-[beta-D-xylopyranosyl-(1 --> 6)]-beta-D-glucopyranoside, 2'-O-beta-D-glucopyranosylsalicin, and 2'-O-beta-D-glucopyranosyl-6'-O-beta-D-xylopyranosylsalicin were isolated along with seven known glycosides. The structures of the new compounds were determined by spectroscopic and chemical means. PMID:11605667

Itoh, A; Tanahashi, T; Nagakura, N; Inoue, K; Kuwajima, H; Wu, H X

2001-10-01

258

Two new glycosides from the florets of Carthamus tinctorius.  

PubMed

Two new glycoside compounds, named saffloquinoside C (1) and (-)-4-hydroxybenzoic acid-4-O-[6'-O-(2?-methylbutyryl)-?-D-glucopyranoside] (2), were isolated from the florets of Carthamus tinctorius. Their structures were elucidated by detailed spectroscopic means including UV, IR, HR-ESI-MS, 1D and 2D NMR, and CD data. Compound 1 was a rare quinochalcone glycoside with six five-membered dioxaspirocycle. PMID:23600648

Jiang, Jian-Shuang; Chen, Zhong; Yang, Ya-Nan; Feng, Zi-Ming; Zhang, Pei-Cheng

2013-01-01

259

[Seasonal fluctuation of flavonol glycosides in Epimedium species].  

PubMed

The seasonal fluctuation of flavonol glycosides in the leaves of Epimedium grandiflorum var. thunbergianum, E. cremeum and E. sempervirens (Berberidaceae) was investigated. The total content of glycosides was shown in the highest quantity at the flowering time, and as the leaves mature it has become stable amount with a little decrease. The suitable period for the harvest of Epimedium leaves was concluded to be two or three months after the flowering time. PMID:2760814

Mizuno, M; Iinuma, M; Tanaka, T; Iwashima, S; Sakakibara, N

1989-04-01

260

Three New Steroidal Glycosides from the Roots of Cynanchum stauntonii  

PubMed Central

Three new steroidal glycosides, named as stauntosides L, M, and N (1–3), along with one known C21 steroidal glycoside, anhydrohirundigenin monothevetoside (4), were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR, HRESI-MS, and chemical methods.

Yu, Jin-Qian; Zhang, Zhi-Hui; Deng, An-Jun; Qin, Hai-Lin

2013-01-01

261

Cardiac Ochronosis  

PubMed Central

We report the case of 67-year-old woman who underwent aortic valve replacement and mitral valve repair due to ochronotic valvular disease (alkaptonuria), which was diagnosed incidentally during cardiac surgery.

Erek, Ersin; Casselman, Filip P.A.; Vanermen, Hugo

2004-01-01

262

Cardiac catheterization  

MedlinePLUS

... amyloidosis Causes of congestive heart failure or cardiomyopathy Coronary artery disease Heart defects that are present at birth ( ... include: Cardiac tamponade Heart attack Injury to a coronary artery Irregular heartbeat Low blood pressure Reaction to the ...

263

Cardiac Rehabilitation  

MedlinePLUS

Cardiac rehabilitation (rehab) is a medically supervised program to help people who have A heart attack Angioplasty or coronary artery bypass grafting for coronary heart disease A heart valve repair or replacement A ...

264

Cardiac MRI  

MedlinePLUS

... from the NHLBI on Twitter. What Is Cardiac MRI? Magnetic resonance imaging (MRI) is a safe, noninvasive test that creates detailed ... and no instruments are inserted into your body. MRI uses radio waves, magnets, and a computer to ...

265

Cardiac Angiosarcoma  

PubMed Central

Despite cardiac metastases are found in about 20% of cancer deaths, the presence of primary cardiac tumors is rare. Most primary tumors are benign, and malignant tumors comprise about 15%. We report a 21-year-old man with fever, dyspnea, and hemoptysis that was diagnosed with angiosarcoma of the right atrium and pulmonary metastasis. Patient was submitted to surgical tumor resection without adjuvant therapy and died four months after diagnosis.

Cardoso, Monique Esteves; Canale, Leonardo Secchin; Ramos, Rosana Grandelle; Salvador Junior, Edson da Silva; Lachtermacher, Stephan

2011-01-01

266

Antioxidant flavonoid glycosides from Evolvulus alsinoides.  

PubMed

Oxidative damage is an established outcome of chronic stress. Thus, the present study was designed to investigate the modulatory role of ethanolic extract of Evolvulus alsinoides (EA) in terms of oxidative alterations at peripheral and central level in rats subjected to chronic unpredictable stress (CUS). CUS exposure for 7 days reduced Cu, Zn superoxide dismutase and catalase activity with increase in glutathione peroxidase activity and lipid peroxidation, while decrease in reduced glutathione level in blood plasma, frontal cortex and hippocampus regions of brain. Oral administration of EA extract at 200mg/kg p.o. normalized these stress induced oxidative alterations with an efficacy similar to that of melatonin. Further, EA extract was taken up for detailed chemical investigation. Two new flavonol-4'-glycoside, kaempferol 4'-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside (3) and kaempferol 4'-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (5) were isolated, along with eight known compounds (1, 2, 4 and 6-10). The structures of new compounds were established by detailed spectroscopic studies, while known compounds were characterized by direct comparison of their reported NMR data. All these compounds were evaluated for their in vitro antioxidant activity. Compounds 3, 5, 9 and 10 at 100 and 200 microg/ml showed significant in vitro antioxidant activity. Therefore, EA may hold great potential in preventing clinical deterioration in stress induced oxidative load and related disorders. PMID:19748554

Kumar, Manmeet; Ahmad, Ausaf; Rawat, Preeti; Khan, Mohammad Faheem; Rasheed, Naila; Gupta, Prasoon; Sathiamoorthy, B; Bhatia, Gitika; Palit, Gautam; Maurya, Rakesh

2010-06-01

267

Heating and reduction affect the reaction with tannins of wine protein fractions differing in hydrophobicity.  

PubMed

During the storage, bottled white wines can manifest haziness due to the insolubilisation of the grape proteins that may 'survive' in the fermentation process. Although the exact mechanism of this occurrence is not fully understood, proteins and tannins are considered two of the key factors involved in wine hazing, since their aggregation leads to the formation of insoluble particles. To better understand this complex interaction, proteins and tannins from the same unfined Pinot grigio wine were separated. Wine proteins were then fractionated by hydrophobic interaction chromatography (HIC). A significant correlation between hydrophobicity of the wine protein fractions and the haze formed after reacting with wine tannins was found, with the most reactive fractions revealing (by SDS-PAGE and RP-HPLC analyses) the predominant presence of thaumatin-like proteins. Moreover, the effects of both protein heating and disulfide bonds reduction (with dithiotreithol) on haze formation in the presence of tannins were assessed. These treatments generally resulted in an improved reactivity with tannins, and this phenomenon was related to both the surface hydrophobicity and composition of the protein fractions. Therefore, haze formation in wines seems to be related to hydrophobic interactions occurring among proteins and tannins. These interactions should occur on hydrophobic tannin-binding sites, whose exposition on the proteins can depend on both protein heating and reduction. PMID:20103151

Marangon, Matteo; Vincenzi, Simone; Lucchetta, Marco; Curioni, Andrea

2010-02-15

268

How to gain insight into the polydispersity of tannins: A combined MS and LC study.  

PubMed

In the context of the potential health benefits of food polyphenols, the bioavailability of tannins (i.e. proanthocyanidins) is a major issue, which is strongly influenced by the polydispersity and the degree of polymerisation of tannins. The average degree of polymerisation (DP) of tannins is usually determined using depolymerisation methods, which do not provide any information about their polymer distribution. Moreover, it is still a challenge to characterise tannin fractions of high polydispersity and/or containing polymers of high molecular weights, due to the limit of detection of direct mass spectrometry (MS) analysis methods. In the present work, the polydispersity of several tannin fractions is investigated by two complementary methods: a MALDI-MS method and a semi-preparative sub-fractionation. Using a combination of these methods we are able to gain insight into the DP distributions of the fractions consisting of tannins of medium and high DP. Moreover combining analyses can be useful to assess and compare the DP distributions of most tannin fractions. PMID:25038686

Mouls, Laetitia; Hugouvieux, Virginie; Mazauric, Jean-Paul; Sommerer, Nicolas; Mazerolles, Gérard; Fulcrand, Hélène

2014-12-15

269

Tropical tannin-rich fodder intake modifies saliva-binding capacity in growing sheep.  

PubMed

We evaluated the effect of feeding dietary tannins from Lysiloma latisiliquum fresh forage on the saliva tannin-binding capacity of hair sheep lambs without previous exposure to tannin-rich (TR) fodder. Twenty-four hair sheep lambs (13.6±3.04 kg LW) were fed a tannin-free diet at the beginning of the experimental period (from day 10 to 13). On day 14, lambs were distributed into three groups (n=8): control group (CG), fed with the tannin-free diet (from D10 to D112); tannin short-term group (TST), fed the basal diet and 650 g of L. latisiliquum forage (from D14 to D55); tannin long-term group (TLT), fed the basal diet and 650 g of L. latisiliquum forage (from D14 to D112). Saliva samples were collected from the mouth of each lamb in the morning before feeding time on D10 and D14 (baseline period), on D49 and D56 (period 1) and on D97 and D112 (period 2). The tannin binding response of salivary protein (?% turbidity) was determined with the haze development test (HDT) using either tannic acid or L. latisiliquum forage acetone extract. A turbidity protein index (TPI) was calculated as (?% turbidity/[salivary protein (mg)]). Differences in HDT and TPI in the different groups were compared by repeated measures ANOVA using Proc Mixed. All groups had similar ?% turbidity throughout the experiment (P>0.05). At baseline and period 1, the TPI of the different groups was similar (P>0.05). On period 2 the TLT group showed higher TPI compared with CG (P<0.05). Meanwhile, CG and TST showed similar salivary TPI. The saliva of hair sheep lambs consuming TR L. latisiliquum fresh fodder (TLT group) increased their TPI compared with control lambs not exposed to tannins. PMID:24093808

Vargas-Magaña, J J; Aguilar-Caballero, A J; Torres-Acosta, J F J; Sandoval-Castro, C A; Hoste, H; Capetillo-Leal, C M

2013-12-01

270

The influence of dietary tannin supplementation on digestive performance in captive black rhinoceros (Diceros bicornis).  

PubMed

Free-ranging browsers such as the black rhinoceros (Diceros bicornis) consume a diet that contains tannins, whereas the diets offered to them in captivity consist mostly of items known to contain hardly any such secondary plant compounds. Tannins could have potentially beneficial effects, including the chelation of dietary iron (iron storage disease is a common problem in black rhinos). Here, we tested the acceptance, and the consequences on digestion variables, of a low-dose tannin supplementation in captive animals. Eight black rhinoceroses from three zoological institutions were used. Faecal output was quantified by total faecal collection. Diets fed were regular zoo diets supplemented with either tannic acid (T, hydrolysable tannin) or quebracho (Q, condensed tannins); overall tannin source intake increased at 5-15 g/kg dry matter (DM) in relation to regular zoo diets. Adaptation periods to the new diets were >2 months. Additional data were taken from one hitherto unpublished study. Data were compared to measurements in the same animals on their regular zoo diets. All animals accepted the new diets without hesitation. There was no influence of tannin supplementation on digestion coefficients of DM and its constituents, or faecal concentrations of short-chain fatty acids or lactate. Water intake did not increase during tannin supplementation. Should the inclusion of dietary tannin sources be an objective in the development of diets for captive rhinoceroses, moderate doses such as used in this study are unlikely to cause relevant depressions of digestive efficiency and will not interfere with bacterial fermentation in a relevant way. PMID:17988348

Clauss, M; Castell, J C; Kienzle, E; Dierenfeld, E S; Flach, E J; Behlert, O; Ortmann, S; Streich, W J; Hummel, J; Hatt, J-M

2007-12-01

271

Glycosidic inhibitors of melanogenesis from leaves of Passiflora edulis.  

PubMed

A new flavonoid glycoside, chrysin 6-C-?-rutinoside (chrysin ?-L-rhamnopyranosyl-(1?6)-C-?-glucopyranoside; 2), and two new triterpene glycosides, (31R)-31-O-methylpassiflorine (7) and (31S)-31-O-methylpassiflorine (8), along with 14 known glycosides, including three flavonoid glycosides, 1, 3, and 4, six triterpene glycosides, 5, 6, and 9-12, three cyano glycosides, 13-15, and two other glycosides, 16 and 17, were isolated from a MeOH extract of the leaves of Passiflora edulis (passion flower; Passifloraceae). The structures of new compounds were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluation of compounds 1-17 against the melanogenesis in the B16 melanoma cells induced with ?-melanocyte-stimulating hormone (?-MSH), three compounds, isoorientin (1), 2, and (6S,9R)-roseoside (17), exhibited inhibitory effects with 37.3-47.2% reduction of melanin content with no, or almost no, toxicity to the cells (90.8-100.2% cell viability) at 100??M. Western blot analysis showed that compound 2 reduced the protein levels of MITF, TRP-1, and tyrosinase, in a concentration-dependent manner while exerted almost no influence on the level of TRP-2, suggesting that this compound inhibits melanogenesis on the ?-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of TRP-1 and tyrosinase. In addition, compounds 1-17 were evaluated for their inhibitory effects against the Epstein?Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. PMID:24130028

Zhang, Jie; Koike, Ryosuke; Yamamoto, Ayako; Ukiya, Motohiko; Fukatsu, Makoto; Banno, Norihiro; Miura, Motofumi; Motohashi, Shigeyasu; Tokuda, Harukuni; Akihisa, Toshihiro

2013-10-01

272

Specific Polyphenols and Tannins are Associated with Defense Against Insect Herbivores in the Tropical Oak Quercus oleoides.  

PubMed

The role of plant polyphenols as defenses against insect herbivores is controversial. We combined correlative field studies across three geographic regions (Northern Mexico, Southern Mexico, and Costa Rica) with induction experiments under controlled conditions to search for candidate compounds that might play a defensive role in the foliage of the tropical oak, Quercus oleoides. We quantified leaf damage caused by four herbivore guilds (chewers, skeletonizers, leaf miners, and gall forming insects) and analyzed the content of 18 polyphenols (including hydrolyzable tannins, flavan-3-ols, and flavonol glycosides) in the same set of leaves using high performance liquid chromatography and mass spectrometry. Foliar damage ranged from two to eight percent per region, and nearly 90% of all the damage was caused by chewing herbivores. Damage due to chewing herbivores was positively correlated with acutissimin B, catechin, and catechin dimer, and damage by mining herbivores was positively correlated with mongolinin A. By contrast, gall presence was negatively correlated with vescalagin and acutissimin B. By using redundancy analysis, we searched for the combinations of polyphenols that were associated to natural herbivory: the combination of mongolinin A and acutissimin B had the highest association to herbivory. In a common garden experiment with oak saplings, artificial damage increased the content of acutissimin B, mongolinin A, and vescalagin, whereas the content of catechin decreased. Specific polyphenols, either individually or in combination, rather than total polyphenols, were associated with standing leaf damage in this tropical oak. Future studies aimed at understanding the ecological role of polyphenols can use similar correlative studies to identify candidate compounds that could be used individually and in biologically meaningful combinations in tests with herbivores and pathogens. PMID:24809533

Moctezuma, Coral; Hammerbacher, Almuth; Heil, Martin; Gershenzon, Jonathan; Méndez-Alonzo, Rodrigo; Oyama, Ken

2014-05-01

273

Human psychometric and taste receptor responses to steviol glycosides.  

PubMed

Steviol glycosides, the sweet principle of Stevia Rebaudiana (Bertoni) Bertoni, have recently been approved as a food additive in the EU. The herbal non-nutritive high-potency sweeteners perfectly meet the rising consumer demand for natural food ingredients in Europe. We have characterized the organoleptic properties of the most common steviol glycosides by an experimental approach combining human sensory studies and cell-based functional taste receptor expression assays. On the basis of their potency to elicit sweet and bitter taste sensations, we identified glycone chain length, pyranose substitution, and the C16 double bond as the structural features giving distinction to the gustatory profile of steviol glycosides. A comprehensive screening of 25 human bitter taste receptors revealed that two receptors, hTAS2R4 and hTAS2R14, mediate the bitter off-taste of steviol glycosides. For some test substances, e.g., stevioside, we observed a decline in sweet intensity at supra-maximum concentrations. This effect did not arise from allosteric modulation of the hTAS1R2/R3 sweet taste receptor but might be explained by intramolecular cross-modal suppression between the sweet and bitter taste component of steviol glycosides. These results might contribute to the production of preferentially sweet and least bitter tasting Stevia extracts by an optimization of breeding and postharvest downstream processing. PMID:22616809

Hellfritsch, Caroline; Brockhoff, Anne; Stähler, Frauke; Meyerhof, Wolfgang; Hofmann, Thomas

2012-07-11

274

Cardiac sarcoidosis.  

PubMed

Cardiac sarcoidosis (CS) is a rare and under-recognized clinical entity that requires a high level of suspicion and low threshold for screening in order to make the diagnosis. CS may manifest in a variety of ways, and its initial presentation can range from asymptomatic electrocardiographic abnormalities to overt heart failure to sudden cardiac death. The aim of this literature review is to provide a comprehensive overview of CS, with an emphasis on clinical manifestations and special diagnostic and management considerations, while highlighting recent studies that have provided new insights into this unique disease. PMID:24969032

Zipse, Matthew M; Sauer, William H

2014-08-01

275

Progesterone derivative binds to cardiac ouabain receptor and shows dissociation between sodium pump inhibition and increased contractile force  

Microsoft Academic Search

DIGITALIS and related steroid glycosides exert two well established action: augmentation of the contractile force of cardiac muscle, the basis for the clinical use of these drugs; and inhibition of Na-K-ATPase, a ubiquitous membrane enzyme concerned with maintenance of transcellular ionic gradients. There is much evidence to support the disputed view that the inotropic effect of the cardiotonic steroids is

Frank S. Labella; Ivan Bihler; Ryung S. Kim

1979-01-01

276

Cattle and sheep develop preference for drinking water containing grape seed tannin.  

PubMed

Ingestion of small amounts of some types of condensed tannins (CTs) by ruminant livestock can provide nutritional, environmental and economic benefits. However, practical methods are needed to make these tannins more available to ruminant livestock. Results from previous trials with crude quebracho and black wattle tannin indicated that cattle and/or sheep would not preferentially drink water containing these tannins. Therefore, we conducted preference trials to determine if cattle and sheep would learn to prefer water containing purified grape seed tannin (GST) that provided up to 2% of their daily dry matter (DM) intake. After gradual exposure to increasing amounts of this tannin in water during a pre-trial period, five adult ewes and five yearling heifers fed lucerne (Medicago sativa) pellets (19% CP) were offered water and several concentrations of GST solutions for either 15 (sheep trial) or 20 days (cattle trial). We measured intake of all liquids daily. Concentrations of blood urea were also measured for heifers when they drank only tannin solutions or water. Both sheep and cattle developed preferences for water with GST in it over water alone (P < 0.01) although this preference appeared earlier in the trial for sheep than for cattle. For the sheep, mean daily intake of water alone and all tannin solutions (in total) was 0.6 and 6.1 l, respectively. For the cattle, mean daily intake of water and all tannin solutions in total was 21.8 and 20.6 l, respectively, in the first half of the trial and 10.8 and 26.1 l, respectively, in the second half of the trial. Compared with the other tannin solutions, both sheep and cattle drank more of the solution with the highest tannin concentration (2% of daily DM intake as GST) than of water on more trial days (P < 0.05). Ingestion of water with the highest concentration of GST reduced blood plasma urea concentration in the cattle by 9% to 14% (P ? 0.10) compared with ingestion of water alone. Results from the trials suggest that providing grape seed and perhaps other CTs via drinking water may be a practical way to introduce CTs into sheep and cattle diets. PMID:23880297

Kronberg, S L; Schauer, C S

2013-10-01

277

Glycosidic Bond Cleavage is Not Required for Phytosteryl Glycoside-Induced Reduction of Cholesterol Absorption in Mice  

PubMed Central

Phytosteryl glycosides occur in natural foods but little is known about their metabolism and bioactivity. Purified acylated steryl glycosides (ASG) were compared with phytosteryl esters (PSE) in mice. Animals on a phytosterol-free diet received ASG or PSE by gavage in purified soybean oil along with tracers cholesterol-d7 and sitostanol-d4. In a three-day fecal recovery study, ASG reduced cholesterol absorption efficiency by 45 ± 6% compared with 40 ± 6% observed with PSE. Four hours after gavage, plasma and liver cholesterol-d7 levels were reduced 86% or more when ASG was present. Liver total phytosterols were unchanged after ASG administration but were significantly increased after PSE. After ASG treatment both ASG and deacylated steryl glycosides (SG) were found in the gut mucosa and lumen. ASG was quantitatively recovered from stool samples as SG. These results demonstrate that ASG reduces cholesterol absorption in mice as efficiently as PSE while having little systemic absorption itself. Cleavage of the glycosidic linkage is not required for biological activity of ASG. Phytosteryl glycosides should be included in measurements of bioactive phytosterols.

Lin, Xiaobo; Ma, Lina; Moreau, Robert A.

2012-01-01

278

Selective hydrolysis of flavonoid glycosides by Curvularia lunata.  

PubMed

Twelve flavonoid glycosides were involved in the biotransformation of the glycosyl moieties by Curvularia lunata 3.4381, and the products were analyzed by UPLC/PDA-Q-TOF-MS(E). Curvularia lunata displayed hydrolyzing activities on the terminal Rha or Glc units of some flavonoid glycosides. Terminal Rha with a 1 ? 2 linkage of isorhamnetin-3-O-neohesperidoside and typhaneoside could be hydrolyzed by Curvularia lunata, but terminal Rha with a 1 ? 6 linkage of rutin, typhaneoside, and quercetin-3-O-apiosyl-(1 ? 2)-[rhamnosyl-(1 ? 6)]-glucoside could not be hydrolyzed. Curvularia lunata could also hydrolyze the Glc of icariin, floramanoside B, and naringin. This is the first report of the hydrolysis of glycosyl units of flavonoid glycosides by Curvularia lunata. A new way to convert naringin to naringenin was found in this research. PMID:24345511

Liu, Jing-Yuan; Yu, He-Shui; Feng, Bing; Kang, Li-Ping; Pang, Xu; Xiong, Cheng-Qi; Zhao, Yang; Li, Chun-Mei; Zhang, Yi; Ma, Bai-Ping

2013-11-01

279

Cornstarch and tannin in phenol–formaldehyde resins for plywood production  

Microsoft Academic Search

The aim of this work is to demonstrate the performances of cornstarch–quebracho tannin-based resins designed as adhesive in the plywood production. In this way, the cornstarch and quebracho tannin was introduced in the classic adhesive formulation in order to supply a part of phenol–formaldehyde (PF). The physical properties (rheological characterization, thermogravimetric analysis and solid phase 13C NMR analysis) of the

Amine Moubarik; Antonio Pizzi; Ahmed Allal; Fatima Charrier; Bertrand Charrier

2009-01-01

280

Inhibitory mechanism of low-carbon steel corrosion by mimosa tannin in sulphuric acid solutions  

Microsoft Academic Search

Mimosa tannin was investigated as inhibitor of low-carbon steel sulphuric acid corrosion in concentrations from 10-5 to 10-1 mol L-1, at the temperature of 298 K in the solutions of pH 1, 2 and 3. The inhibitor effectiveness increases with increase in concentration. The adsorptive behaviour of mimosa tannin in solutions of pH 1 and 2 may be approximated, both

S. Martinez; I. Štern

2001-01-01

281

Ability of a salivary intrinsically unstructured protein to bind different tannin targets revealed by mass spectrometry.  

PubMed

Astringency is thought to result from the interaction between salivary proline-rich proteins (PRP) that belong to the intrinsically unstructured protein group (IUP), and tannins, which are phenolic compounds. IUPs have the ability to bind several and/or different targets. At the same time, tannins have different chemical features reported to contribute to the sensation of astringency. The ability of both electrospray ionization mass spectrometry and tandem mass spectrometry to investigate the noncovalent interaction occurring between a human salivary PRP, IB5, and a model tannin, epigallocatechin 3-O-gallate (EgCG), has been reported. Herein, we extend this method to study the effect of tannin chemical features on their interaction with IB5. We used five model tannins, epigallocatechin (EgC), epicatechin 3-O-gallate (ECG), epigallocatechin 3-O-gallate (EgCG), procyanidin dimer B2 and B2 3'-O-gallate, which cover the main tannin chemical features: presence of a gallate moiety (galloylation), the degree of polymerization, and the degree of B ring hydroxylation. We show the ability of IB5 to bind these tannins. We report differences in stoichiometries and in stability of the IB5•1 tannin complexes. These results demonstrate the main role of hydroxyl groups in these interactions and show the involvement of hydrogen bonds. Finally, these results are in line with sensory analysis, by Vidal et al. (J Sci Food Agric 83:564-573, 2003) pointing out that the chain length and the level of galloylation are the main factors affecting astringency perception. PMID:20665010

Canon, Francis; Giuliani, Alexandre; Paté, Franck; Sarni-Manchado, Pascale

2010-09-01

282

Role of tannin-binding salivary proteins and tannase-producing bacteria in the acclimation of the Japanese wood mouse to acorn tannins.  

PubMed

We studied the defense mechanisms against the negative effects of tannins in acorns by using the Japanese wood mouse (Apodemus speciosus) and acorns of a Japanese deciduous oak Quercus crispula, which contain 9.9% tannins on a dry weight basis. For the experiment, we allocated 26 wood mice into two groups: acclimated (N = 12) and nonacclimated (N = 14). Mice in the nonacclimated group were fed only acorns for 10 d after 4 wk of receiving a tannin-free diet. In contrast, mice in the acclimated group received ca. 3 g acorns daily in addition to the tannin-free diet for the first 4 wk, then they were fed only acorns for 10 d. Body weight, food intake, and digestibility were monitored. In addition, the amount of salivary proline-rich proteins (PRPs) and abundance of tannase-producing bacteria (TPB) in the feces of mice were measured. Of the 14 mice in the nonacclimated group, 8 died, whereas only 1 of the 12 in the acclimated group died. During the first 5 d of feeding acorns only, mice in the nonacclimated group lost, on average, 17.5% of their body mass, while those in the acclimated group lost only 2.5%. Food intake, dry matter digestibility, and nitrogen digestibility were higher in the acclimated group than in the nonacclimated group. The results indicate that wood mice can mitigate the negative effects of tannins by acclimation. Path analysis revealed that increased secretion of PRPs and abundance of Lactobacillus type of TPB might explain the acclimation to tannins. PMID:16770711

Shimada, Takuya; Saitoh, Takashi; Sasaki, Eiki; Nishitani, Yosuke; Osawa, Ro

2006-06-01

283

Chemical and biological properties of quinochalcone C-glycosides from the florets of Carthamus tinctorius.  

PubMed

Quinochalcone C-glycosides are regarded as characteristic components that have only been isolated from the florets of Carthamus tinctorius. Recently, quinochalcone C-glycosides were found to have multiple pharmacological activities, which has attracted the attention of many researchers to explore these compounds. This review aims to summarize quinochalcone C-glycosides' physicochemical properties, chromatographic behavior, spectroscopic characteristics, as well as their biological activities, which will be helpful for further study and development of quinochalcone C-glycosides. PMID:24335575

Yue, Shijun; Tang, Yuping; Li, Shujiao; Duan, Jin-Ao

2013-01-01

284

Effect of condensed tannins addition on the astringency of red wines.  

PubMed

Astringency has been defined as a group of sensations involving dryness, tightening, and shrinking of the oral surface. It has been accepted that astringency is due to the tannin-induced interaction and/or precipitation of the salivary proline-rich proteins (PRPs) in the oral cavity, as a result of the ingestion of food products rich in tannins, for example, red wine. The sensory evaluation of astringency is difficult, and the existence of fast and reliable methods to its study in vitro is scarce. So, in this work, the astringency of red wine supplemented with oligomeric procyanidins (condensed tannins), and the salivary proteins (SP) involved in its development were evaluated by high-performance liquid chromatography analysis of human saliva after its interaction with red wine and by sensorial evaluation. The results show that for low concentration of tannins, the decrease of acidic PRPs and statherin is correlated with astringency intensity, with these families having a high relative complexation and precipitation toward condensed tannins comparatively to the other SP. However, for higher concentrations of tannins, the relative astringency between wines seems to correlate's to the glycosylated PRPs changes. This work shows for the first time that the several families of SP could be involved in different stages of the astringency development. PMID:22086902

Soares, Susana; Sousa, André; Mateus, Nuno; de Freitas, Victor

2012-02-01

285

Synthesis and Photochromic Properties of Configurationally Varied Azobenzene Glycosides  

PubMed Central

Spatial orientation of carbohydrates is a meaningful parameter in carbohydrate recognition processes. To vary orientation of sugars with temporal and spatial resolution, photosensitive glycoconjugates with favorable photochromic properties appear to be opportune. Here, a series of azobenzene glycosides were synthesized, employing glycoside synthesis and Mills reaction, to allow “switching” of carbohydrate orientation by reversible E/Z isomerization of the azobenzene N=N double bond. Their photochromic properties were tested and effects of azobenzene substitution as well as the effect of anomeric configuration and the orientation of the sugars 2-hydroxy group were evaluated.

Chandrasekaran, Vijayanand; Johannes, Eugen; Kobarg, Hauke; Sonnichsen, Frank D; Lindhorst, Thisbe K

2014-01-01

286

Balanitoside, a furostanol glycoside, and 6-methyldiosgenin from Balanites aegyptiaca.  

PubMed

In addition to a known spirostanol glycoside, balanitin-3, and a new sapogenol, 6-methyldiosgenin, a new furostanol saponin, balanitoside has been isolated from the fruits (mesocarp) of Balanites aegyptiaca. The structure of the glycoside has been determined as 26-O-beta-D-glucopyranosyl-3 beta, 22,26-trihydroxy-furost-5-ene 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D- glucopyranosyl-(1-->4)-beta-D-glucopyranoside, on the basis of spectroscopic and chemical evidence. PMID:1368863

Hosny, M; Khalifa, T; Cali?, I; Wright, A D; Sticher, O

1992-10-01

287

Steroidal glycosides from Reineckia carnea herba and their antitussive activity.  

PubMed

Two new steroidal glycosides, 1?,3?-dihydroxy-5?-pregn-16-en-20-one 3-O-?-L-rhamnopyranoside (1) and 1?,3?,27-trihydroxycholest-16-en-22-one 1,3-di-O-?-L-rhamnoside (2), along with seven known steroidal glycosides (3-9), were isolated from Reineckia carnea herba. Their structures were determined by detailed analysis of their 1D- and 2D-NMR and MS spectra. Compound 9 was isolated for the first time from the Reineckia genus. Except for 8, compounds 2, 3, 4, 5, 6, 7, and 9 displayed clear in vitro antitussive activity. PMID:23670621

Han, Na; Chen, Ling Li; Wang, Yao; Xue, Rui; Zou, Li Bo; Liu, Fang; Yin, Jun

2013-06-01

288

Lipoxygenase inhibiting ethyl substituted glycoside from Symplocos racemosa.  

PubMed

Phytochemical investigation of Symplocos racemosa resulted in the isolation of a new ethyl substituted glycoside, 1-ethyl brachiose-3'-acetate (1) along with four known compounds ketochaulmoogric acid (2), nonaeicosanol (3), triacontyl palmitate (4) and methyl triacontanoate (5). The substitution of ethyl group on 1 was natural because during the course of extraction and purification ethanol was not used. The structural elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR analysis, including COSY, HMQC, and HMBC correlations. The glycoside 1 and triacontyl palmitate (4) displayed the inhibitory potential against lipoxygenase and urease enzyme, respectively. PMID:15938197

Abbasi, Muhammad Athar; Ahmad, Viqar Uddin; Zubair, Muhammad; Nawaz, Sarfraz A; Lodhi, Muhammad Arif; Farooq, Umar; Choudhary, M Iqbal

2005-07-01

289

Xanthone glycoside constituents of Swertia kouitchensis with ?-glucosidase inhibitory activity.  

PubMed

Ten new xanthone glycosides, kouitchensides A-J (1-10), and 11 known analogues were isolated from an n-butanol fraction of Swertia kouitchensis. The structures of these glycosides were determined on the basis of extensive spectroscopic data interpretation and comparison with data reported in the literature. In an in vitro test, compounds 2, 4, 5, 6, 11, 12, and 13 (IC50 values in the range 126 to 451 ?M) displayed more potent inhibitory effects against ?-glucosidase activity than the positive control, acarbose (IC50 value of 627 ?M). PMID:23805995

Wan, Luo-Sheng; Min, Qiu-Xia; Wang, Yong-Long; Yue, Yao-Dong; Chen, Jia-Chun

2013-07-26

290

Phenylethanoid and flavone glycosides from Ruellia tuberosa L.  

PubMed

A new phenylethanoid glycoside, isocassifolioside (8), and two new flavone glycosides, hispidulin 7-O-?-L-rhamnopyranosyl-(1'? ? 2?)-O-?-D-glucuronopyranoside (11) and pectolinaringenin 7-O-?-L-rhamnopyranosyl-(1'? ? 2?)-O-?-D-glucuronopyranoside (12) were isolated from the aerial portions of Ruellia tuberosa L., together with verbascoside (1), isoverbascoside (2), nuomioside (3), isonuomioside (4), forsythoside B (5), paucifloside (6), cassifolioside (7), hispidulin 7-O-?-D-glucuronopyranoside (9) and comanthoside B (10). The structure elucidations were based on analyses of chemical and spectroscopic data including 1D- and 2D-NMR. The isolated compounds 1-12 exhibited radical scavenging activity using ORAC assay. PMID:22447282

Phakeovilay, Chiobouaphong; Disadee, Wannaporn; Sahakitpichan, Poolsak; Sitthimonchai, Somkit; Kittakoop, Prasat; Ruchirawat, Somsak; Kanchanapoom, Tripetch

2013-01-01

291

Caucasicosides E-M, furostanol glycosides from Helleborus caucasicus.  

PubMed

Nine furostanol glycosides, namely caucasicosides E-M, were isolated from the MeOH extract of the leaves of Helleborus caucasicus, along with 11 known compounds including nine furostanol glycosides, a bufadienolide and an ecdysteroid. Their structures were established by the extensive use of 1D and 2D NMR experiments along with ESIMS(n) analyses. The steroidal composition of leaves of H. caucasicus shows as particular feature the occurrence of steroidal compounds belonging to the 5? series, unusual for Helleborus species, and in particular, caucasicosides F-H are based on a 5?-polyhydroxylated steroidal aglycon never reported before. PMID:21893324

Muzashvili, Tamar; Perrone, Angela; Napolitano, Assunta; Kemertelidze, Ether; Pizza, Cosimo; Piacente, Sonia

2011-12-01

292

Annotation and comparative analysis of the glycoside hydrolase genes in Brachypodium distachyon  

Microsoft Academic Search

BACKGROUND: Glycoside hydrolases cleave the bond between a carbohydrate and another carbohydrate, a protein, lipid or other moiety. Genes encoding glycoside hydrolases are found in a wide range of organisms, from archea to animals, and are relatively abundant in plant genomes. In plants, these enzymes are involved in diverse processes, including starch metabolism, defense, and cell-wall remodeling. Glycoside hydrolase genes

Ludmila Tyler; Jennifer N Bragg; Jiajie Wu; Xiaohan Yang; Gerald A Tuskan; John P Vogel

2010-01-01

293

Woodfordin C, a macro-ring hydrolyzable tannin dimer with antitumor activity, and accompanying dimers from Woodfordia fruticosa flowers.  

PubMed

Three new dimeric hydrolyzable tannins, woodfordins A, B and C, along with seven known hydrolyzable tannins, including oenothein B, a dimer exhibiting marked host-mediated antitumor activity, were isolated from an Indonesian crude drug, Sidowayah [dried flowers of Woodfordia fruticosa (L.) Kurz (Lythraceae)]. The structures of the new tannins were elucidated based on chemical and spectral evidence. Woodfordin C, having a macro-ring structure, was also found to exhibit a significant antitumor activity. PMID:2393947

Yoshida, T; Chou, T; Nitta, A; Miyamoto, K; Koshiura, R; Okuda, T

1990-05-01

294

Hydrolysis of black soybean isoflavone glycosides by Bacillus subtilis natto.  

PubMed

Hydrolysis of isoflavone glycosides by Bacillus subtilis natto NTU-18 in black soymilk is reported. At the concentration of 3-5% (w/v), black soymilk in flask cultures, the isoflavones, daidzin, and genistin were highly deglycosylated within 24 h. Deglycosylation of isoflavones was further carried out in a 7-l fermenter with 5% black soymilk. During the fermentation, viable cells increased from 10(3) to 10(9) CFU ml(-1) in 15 h, and the activity of beta-glucosidase appeared at 8 h after inoculation and reached a maximum (3.3 U/ml) at 12 h, then decreased rapidly. Deglycosylation of isoflavone glycosides was observed at the same period, the deglycosylation rate of daidzin and genistin at 24 h was 100 and 75%, respectively. It is significantly higher than the previous reports of fermentation with lactic acid bacteria. In accordance with the deglycosylation of isoflavone glycosides, the estrogenic activity of the 24 h fermented black soymilk for ERbeta estrogen receptor increased to threefold; meanwhile, the fermented broth activated ERalpha estrogen receptor to a less extent than ERbeta. These results suggest that this fermentation effectively hydrolyzed the glycosides from isoflavone in black soymilk and the fermented black soymilk has the potential to be applied to selective estrogen receptor modulator products. PMID:16715232

Kuo, Lun-Cheng; Cheng, Wei-Yi; Wu, Ren-Yu; Huang, Ching-Jang; Lee, Kung-Ta

2006-11-01

295

Lipoxygenase inhibiting ethyl substituted glycoside from Symplocos racemosa  

Microsoft Academic Search

Phytochemical investigation of Symplocos racemosa resulted in the isolation of a new ethyl substituted glycoside, 1-ethyl brachiose-3?-acetate (1) along with four known compounds ketochaulmoogric acid (2), nonaeicosanol (3), triacontyl palmitate (4) and methyl triacontanoate (5). The substitution of ethyl group on 1 was natural because during the course of extraction and purification ethanol was not used. The structural elucidation of

Muhammad Athar Abbasi; Viqar Uddin Ahmad; Muhammad Zubair; Sarfraz A. Nawaz; Muhammad Arif Lodhi; Umar Farooq; M. Iqbal Choudhary

2005-01-01

296

New glycosides of acetophenone derivatives and phenylpropanoids from Juniperus occidentalis.  

PubMed

New glycosides of seven acetophenone derivatives (1-7) and two phenylpropanoids (8, 9), named juniperosides III-XI, have been isolated from the MeOH extract of the leaves and stems of Juniperus occidentalis Hook. (Cupressaceae), together with eleven other known compounds. The structures of these compounds have been successfully elucidated using a variety of spectroscopic techniques. PMID:22847379

Inatomi, Yuka; Murata, Hiroko; Inada, Akira; Nakanishi, Tsutomu; Lang, Frank A; Murata, Jin; Iinuma, Munekazu

2013-04-01

297

Glycosidic constituents from the roots and rhizomes of Melicope pteleifolia.  

PubMed

Seven new diglycosidic constituents, named pteleifosides A-G (1-7), along with ten known glycosides, were isolated from the roots and rhizomes of Melicope pteleifolia (Champ. ex Benth.) T. Hartley. The structures of the isolated compounds were established on the basis of chemical and spectroscopic methods, mainly 1D and 2D NMR data and mass spectrometry. PMID:23010492

Zhang, Yang; Yang, Li-Jun; Jiang, Kun; Tan, Chang-Heng; Tan, Jun-Jie; Yang, Pei-Ming; Zhu, Da-Yuan

2012-11-01

298

Hydroxycinnamoyl ester glycosides and saponins from flowers of Verbascum phlomoides.  

PubMed

A new iridoid ester glycoside acylated with p-coumaric acid was isolated from the flowers of Verbascum phlomoides, together with one known one, specioside. Caffeic acid esters, verbascoside and forsythoside B were found as minor constituents. A new saponin was also obtained and identified as desrhamnosylverbascosaponin. PMID:8987909

Klimek, B

1996-12-01

299

Two new flavonol glycosides from Gymnema sylvestre and Euphorbia ebracteolata  

Microsoft Academic Search

Two new flavonol glycosides, namely kaempferol 3-O-?-d-glucopyranosyl-(1?4)-?-l-rhamnopyranosyl-(1?6)-?-d-galactopyranoside (1) and quercetin 3-O-6?-(3-hydroxyl-3-methylglutaryl)-?-d-glucopyranoside (2), have been isolated from the aerial parts of Gymnema sylvestre and Euphorbia ebracteolata, respectively. Their structures were determined on the basis of chemical and spectroscopic methods.

Xin Liu; Wencai Ye; Biao Yu; Shouxun Zhao; Houming Wu; Chuntao Che

2004-01-01

300

Sesquiterpene lactone glycosides from the roots of Ferula varia.  

PubMed

Seven new sesquiterpene lactone glycosides (1-7) were isolated from the H2O-soluble fraction from the MeOH extract of the roots of Ferula varia. Their structures were elucidated by extensive spectroscopic analyses. The absolute configurations of compounds 1 and 2 were determined by modified Mosher's method. PMID:22790827

Kurimoto, Shin-ichiro; Suzuki, Kyoko; Okasaka, Mamoru; Kashiwada, Yoshiki; Kodzhimatov, Olimjion Kakhkharovich; Takaishi, Yoshihisa

2012-01-01

301

Hydrolytical instability of hydroxyanthraquinone glycosides in pressurized liquid extraction.  

PubMed

Hydroxyanthraquinones represent a group of pharmacologically active compounds characteristic for plants of the Rumex and Rheum genera. These compounds in the human intestine act as laxative compounds. As they cause the greatest side effects and are often abused by the public, their accurate analysis in plants and plant-derived laxatives is much needed. To isolate compounds from plants, pressurized liquid extraction (PLE) is frequently applied. The technique has been regarded, so far, as very effective, even in isolation of sensitive compounds for which exposure time in high temperature has a negative impact. This work demonstrates some interesting and surprising results accompanying PLE of hydroxyanthraquinones from the Rumex crispus L. root using methanol/water mixtures as extractant. The presented results demonstrate that glycoside forms of hydroxyanthraquinones (emodin-8-O-?-D-glucopyranoside, chrysophanol-8-O-?-D-glucopyranoside, and physcion-8-O-?-D-glucopyranoside) are hydrolytically unstable even in the short-lasting PLE. The increase of water concentration in the extractant leads to the increase of the transformation degree of the glycoside forms to the corresponding aglycones (emodin, chrysophanol, and physcion), increasing the concentration of the latter. The rise in the PLE temperature accelerates the hydrolytical degradation of the glycoside forms. The extension of the extraction time also intensifies this process. The presented results show that extraction of glycosides using extractants containing water can lead to false conclusions about the chemical composition of plants. PMID:24652155

Wianowska, Dorota

2014-05-01

302

Absorption, metabolism and elimination of strophanthus glycosides in man  

Microsoft Academic Search

In 33 healthy male volunteers, given a single oral and intravenous dose of cymarin (k-strophanthin-a), k-strophanthoside (k-strophanthin-?) and ouabain (g-strophanthin), enteral absorption and renal excretion of these glycosides and their metabolites were investigated by radioimmunoassay and HPLC.

H. Strobach; K. E. Wirth; K. Rojsathaporn

1986-01-01

303

Glycosidation of Methanol with Ribose: An Interdisciplinary Undergraduate Laboratory Experiment  

ERIC Educational Resources Information Center

This exercise provides students hands-on experience with the topics of glycosidation, hemiacetal and acetal formation, proton nuclear magnetic resonance ([superscript 1]H NMR) spectroscopy, and kinetic and thermodynamic product formation. In this laboratory experiment, the methyl acetal of ribose is synthesized, and the kinetic and thermodynamic…

Simon, Erin; Cook, Katie; Pritchard, Meredith R.; Stripe, Wayne; Bruch, Martha; Bendinskas, Kestutis

2010-01-01

304

A New Flavanonol Glycoside from Adansonia digitata Roots.  

PubMed

A new flavanonol glycoside isolated from the roots of Adansonia digitata has been characterised as 3,7-dihydroxy flavan-4-one-5-O-beta- D-galactopyranosyl (1 --> 4)-beta- D-glucopyranoside on the basis of degradation, spectral and chemical studies. PMID:17340272

Chauhan, J S; Kumar, S; Chaturvedi, R

1984-02-01

305

Curation of characterized glycoside hydrolases of Fungal origin  

PubMed Central

Fungi produce a wide range of extracellular enzymes to break down plant cell walls, which are composed mainly of cellulose, lignin and hemicellulose. Among them are the glycoside hydrolases (GH), the largest and most diverse family of enzymes active on these substrates. To facilitate research and development of enzymes for the conversion of cell-wall polysaccharides into fermentable sugars, we have manually curated a comprehensive set of characterized fungal glycoside hydrolases. Characterized glycoside hydrolases were retrieved from protein and enzyme databases, as well as literature repositories. A total of 453 characterized glycoside hydrolases have been cataloged. They come from 131 different fungal species, most of which belong to the phylum Ascomycota. These enzymes represent 46 different GH activities and cover 44 of the 115 CAZy GH families. In addition to enzyme source and enzyme family, available biochemical properties such as temperature and pH optima, specific activity, kinetic parameters and substrate specificities were recorded. To simplify comparative studies, enzyme and species abbreviations have been standardized, Gene Ontology terms assigned and reference to supporting evidence provided. The annotated genes have been organized in a searchable, online database called mycoCLAP (Characterized Lignocellulose-Active Proteins of fungal origin). It is anticipated that this manually curated collection of biochemically characterized fungal proteins will be used to enhance functional annotation of novel GH genes. Database URL: http://mycoCLAP.fungalgenomics.ca/

Murphy, Caitlin; Powlowski, Justin; Wu, Min; Butler, Greg; Tsang, Adrian

2011-01-01

306

Cardiac optogenetics  

PubMed Central

Optogenetics is an emerging technology for optical interrogation and control of biological function with high specificity and high spatiotemporal resolution. Mammalian cells and tissues can be sensitized to respond to light by a relatively simple and well-tolerated genetic modification using microbial opsins (light-gated ion channels and pumps). These can achieve fast and specific excitatory or inhibitory response, offering distinct advantages over traditional pharmacological or electrical means of perturbation. Since the first demonstrations of utility in mammalian cells (neurons) in 2005, optogenetics has spurred immense research activity and has inspired numerous applications for dissection of neural circuitry and understanding of brain function in health and disease, applications ranging from in vitro to work in behaving animals. Only recently (since 2010), the field has extended to cardiac applications with less than a dozen publications to date. In consideration of the early phase of work on cardiac optogenetics and the impact of the technique in understanding another excitable tissue, the brain, this review is largely a perspective of possibilities in the heart. It covers the basic principles of operation of light-sensitive ion channels and pumps, the available tools and ongoing efforts in optimizing them, overview of neuroscience use, as well as cardiac-specific questions of implementation and ideas for best use of this emerging technology in the heart.

2013-01-01

307

Cardiac optogenetics.  

PubMed

Optogenetics is an emerging technology for optical interrogation and control of biological function with high specificity and high spatiotemporal resolution. Mammalian cells and tissues can be sensitized to respond to light by a relatively simple and well-tolerated genetic modification using microbial opsins (light-gated ion channels and pumps). These can achieve fast and specific excitatory or inhibitory response, offering distinct advantages over traditional pharmacological or electrical means of perturbation. Since the first demonstrations of utility in mammalian cells (neurons) in 2005, optogenetics has spurred immense research activity and has inspired numerous applications for dissection of neural circuitry and understanding of brain function in health and disease, applications ranging from in vitro to work in behaving animals. Only recently (since 2010), the field has extended to cardiac applications with less than a dozen publications to date. In consideration of the early phase of work on cardiac optogenetics and the impact of the technique in understanding another excitable tissue, the brain, this review is largely a perspective of possibilities in the heart. It covers the basic principles of operation of light-sensitive ion channels and pumps, the available tools and ongoing efforts in optimizing them, overview of neuroscience use, as well as cardiac-specific questions of implementation and ideas for best use of this emerging technology in the heart. PMID:23457014

Entcheva, Emilia

2013-05-01

308

Wirkung von Tannin und Adlerfarn auf die Fertilitaet von Maeusen (Effects of Tannin and Bracken Fern on the Fertility of Mice).  

National Technical Information Service (NTIS)

In a 3-generation test on mice the influence of bracken fern and one of his possibly important constituent parts - tannin - on the fertility was investigated. The substances were given as food additives. A negative influence could not be observed in any c...

A. E. our R. Hruby

1980-01-01

309

Influence of the glycosylation of human salivary proline-rich proteins on their interactions with condensed tannins.  

PubMed

Binding of condensed tannins to salivary proteins is supposed to be involved in their astringency. First, complexes arising from the interaction of saliva from two individuals and tannins were studied. Then interaction mixture models containing purified saliva proteins were developed. The highest polymerized tannins predominantly precipitated together with the salivary proteins. Electrophoresis of proteins in combination with thiolysis analysis of tannins indicated proline-rich protein (PRP)-polyphenol complexes in precipitated fractions and also in the soluble ones with individual differences. Individual salivas exhibiting different protein patterns were discriminated with regard to their ability to interact with tannins. From binding studies with purified classes of salivary proteins, interactions were shown to depend on the nature of the protein, in particular on their glycosylation state. For low concentrations of tannins, glycosylated PRP-tannin interactions led to complexes that remained soluble, whereas those arising from nonglycosylated PRP-tannin interactions were precipitated. This finding could indicate that under physiological conditions, complexes involving glycosylated proteins maintain part of the lubrication of the oral cavity, whereas tannin trapping leads to a lower astringency perception. PMID:18808139

Sarni-Manchado, Pascale; Canals-Bosch, Joan-Miguel; Mazerolles, Gérard; Cheynier, Véronique

2008-10-22

310

Condensed tannins inhibit house fly (Diptera: Muscidae) development in livestock manure.  

PubMed

Reducing chemical use for suppressing internal and external parasites of livestock is essential for protecting environmental health. Although plant condensed tannins are known to suppress gastro-intestinal parasites in small ruminants, no research on the effects of tannins on external arthropod populations such as the house fly, Musca domestica L., have been conducted. We examined the impact of plant material containing condensed tannins on house fly development. Prairie acacia (Acacia angustissima (Mill.), Kuntze variety hirta (Nutt.) B.L. Rob.) herbage, panicled tick-clover (Desmodium paniculatum (L.) DC.) herbage, and quebracho (Shinopsis balansae Engl.) extracts were introduced at rates of 1, 3 or 5% condensed tannins/kg beef cattle, dairy cattle, and goat manure, respectively. In a second experiment, we also introduce purified catechin at 1 or 3% of dairy manure dry matter and measured its impact on house fly development. For the house flies used in these experiments, the following was recorded: percent fly emergence (PFE), average daily gain (ADG), and average fly weight (AFW). No effects (P>0.05) in house fly development were measured in the caprine manure. Prairie acacia (20.9% condensed tannins) had no effect on house flies developing in either bovine manures. Tick clover (4.9% condensed tannins) had a negative effect on all three quantifiable variables of house fly development in the bovine manures, whereas quebracho extract (64.0% condensed tannins) at the 3 and 5% rate reduced fly emergence in beef manure and average daily gain in dairy manure. The application of purified catechin at 3%, but not 1%, reduced fly PFE, ADG, and AFW. PMID:22217775

Littlefield, Kimberly A; Muir, James P; Lambert, Barry D; Tomberlin, Jeffery K

2011-12-01

311

Antiproliferative activity, antioxidant capacity and tannin content in plants of semi-arid northeastern Brazil.  

PubMed

The objective of this study was to evaluate antiproliferative activity, antioxidant capacity and tannin content in plants from semi-arid northeastern Brazil (Caatinga). For this study, we selected 14 species and we assayed the methanol extracts for antiproliferative activity against the HEp-2 (laryngeal cancer) and NCI-H292 (lung cancer) cell lines using the (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazole) (MTT) method. In addition, the antioxidant activity was evaluated with the DPPH (2,2-diphenyl-2-picrylhydrazyl) assay, and the tannin content was determined by the radial diffusion method. Plants with better antioxidant activity (expressed in a dose able to decrease the initial DPPH concentration by 50%, or IC50) and with higher levels of tannins were: Poincianella pyramidalis (42.95±1.77 µg/mL IC50 and 8.17±0.64 tannin content), Jatropha mollissima (54.09±4.36µg/mL IC50 and 2.35±0.08 tannin content) and Anadenanthera colubrina (73.24±1.47 µg/mL IC50 and 4.41±0.47 tannin content). Plants with enhanced antiproliferative activity (% living cells) were Annona muricata (24.94±0.74 in NCI-H292), Lantana camara (25.8±0.19 in NCI-H292), Handroanthus impetiginosus (41.8±0.47 in NCI-H292) and Mentzelia aspera (45.61±1.94 in HEp-2). For species with better antioxidant and antiproliferative activities, we suggest future in vitro and in vivo comparative studies with other pharmacological models, and to start a process of purification and identification of the possible molecule(s) responsible for the observed pharmacological activity. We believe that the flora of Brazilian semi-arid areas can be a valuable source of plants rich in tannins, cytotoxic compounds and antioxidant agents. PMID:21107308

Gomes de Melo, Joabe; de Sousa Araújo, Thiago Antônio; Thijan Nobre de Almeida e Castro, Valérium; Lyra de Vasconcelos Cabral, Daniela; do Desterro Rodrigues, Maria; Carneiro do Nascimento, Silene; Cavalcanti de Amorim, Elba Lúcia; de Albuquerque, Ulysses Paulino

2010-01-01

312

Condensed tannins and flavonoids from the forage legume sulla (Hedysarum coronarium).  

PubMed

The condensed tannin concentrations and composition and the characterization of the phenolic constituents in the leaves of the forage legume sulla (Hedysarum coronarium), a biennial forage legume found in temperate agricultural regions, were studied. The colorimetric butanol-HCl assay was used for the quantitation of the seasonal condensed tannin concentrations in the leaves of sulla. Fractionation of extracts on Sephadex LH-20 using step elution with aqueous methanol, followed with aqueous acetone or gradient elution with water, aqueous methanol, and aqueous acetone, gave condensed tannin and flavonoid fractions. The chemical characteristics of the purified condensed tannin fractions were studied by acid-catalyzed degradation with benzyl mercaptan and electrospray ionization mass spectrometry (ESI-MS). Thiolysis revealed that epigallocatechin was the major extender unit (15-75%) while gallocatechin was the major terminal unit (50-66%), thus indicating the extractable sulla condensed tannin fraction as the prodelphinidin type. Condensed tannin oligomers to polymers obtained from Sephadex LH-20 gradient fractions ranged between 2.9 and 46 mDP. The homo- and heterogeneous oligomer ions in condensed tannin gradient fractions detected by ESI-MS ranged from 2 to 10 DP and are consistent with the values obtained by thiolysis (2.9-6.9 DP). Lower molecular weight phenolics, including flavonoids and phenolic acids, were characterized by liquid chromatography atmospheric pressure chemical ionization mass spectrometry (LC-APCI/MS) and ESI/MS/MS on a linear ion trap. The flavonoids extracted with aqueous acetone and methanol from sulla leaves and identified included kaempferol, rutin, quercetin-7-O-?-L-rhamnosyl-3-O-glucosylrhamnoside, quercetin-3-O-?-L-rhamnosyl-7-O-glucoside, kaempferol-3-O-?-D-glucoside-dirhamnoside, genistein-7-O-?-D-glucosyl-6?-O-malonate, formononetin-7-O-?-D-glucoside-6?-O-malonate, and afrormosin and the phenolic acid chlorogenic acid. PMID:21780793

Tibe, Olekile; Meagher, Lucy P; Fraser, Karl; Harding, David R K

2011-09-14

313

Rigidity, conformation, and solvation of native and oxidized tannin macromolecules in water-ethanol solution  

NASA Astrophysics Data System (ADS)

We studied by light scattering and small angle x-rays scattering (SAXS) conformations and solvation of plant tannins (oligomers and polymers) in mixed water-ethanol solutions. Their structures are not simple linear chains but contain about 6% of branching. Ab initio reconstruction reveals that monomers within a branch are closely bound pairwise. The chains are rather rigid, with the Kuhn length b=13+/-3 nm, corresponding to about 35 linearly bound monomers. Contribution of solvation layer to SAXS intensity varies in a nonmonotonic way with ethanol content ?A, which is an indication of amphipathic nature of tannin molecules. Best solvent composition ?AB is a decreasing function of polymerization degree N, in agreement with increasing water solubility of tannins with N. Polymers longer than b present a power-law behavior I~Q-d in the SAXS profile at high momentum transfer Q. The monotonic decrease in d with increasing ?A (from 2.4 in water to 1.9 in ethanol) points that the tannins are more compact in water than in ethanol, presumably due to attractive intramolecular interactions in water. Tannins were then oxidized in controlled conditions similar to real biological or food systems. Oxidation does not produce any intermolecular condensation, but generates additional intramolecular links. Some oxidation products are insoluble in water rich solvent. For that reason, we identify these species as a fraction of natural tannins called ``T1'' in the notation of Zanchi et al. [Langmuir 23, 9949 (2007)]. Within the fraction left soluble after oxidation, conformations of polymeric tannins, despite their higher rigidity, remain sensitive to solvent composition.

Zanchi, Dražen; Konarev, Petr V.; Tribet, Christophe; Baron, Alain; Svergun, Dmitri I.; Guyot, Sylvain

2009-06-01

314

Salivary proline-rich proteins in mammals: Roles in oral homeostasis and counteracting dietary tannin.  

PubMed

We review information on the structure of proline-rich proteins (PRPs), their various functions related to oral homeostasis and dietary tannin, and the structural basis of these functions. Consideration of the multifunctional nature of these salivary proteins helps explain both the subtle and large variations found in structure and secretion rates both within individuals and between species. We propose that the ancestral function of PRPs is in maintaining oral homeostasis and that counteracting dietary tannins by binding with them is a derived function. PRPs are effective in oral homeostasis at low secretion levels, whereas counteracting tannin depends on high secretion levels. In the dietary habits ranging from carnivores through omnivores to exclusively planteaters, the dietary nitrogen level is progressively reduced, and plant allelochemical intake, including tannins, increases. We suggest that during this evolution from meat-eater to plant-eater, there was some point in omnivory at which selective pressure from nitrogen limitations, arising from a low nitrogen/high tannin diet, became sufficiently great for the evolution of increased secretion level and diversification of PRPs for dealing with tannin. If this hypothesis is correct, carnivorous mammals should secrete low levels of PRPs for oral homeostasis, but should never secrete high levels, unless they are secondarily carnivorous. Omnivores consuming a diet of very little animal tissue but higher levels of tannin-containing foliage or fruit should generally have the capacity to produce high levels of salivary PRPs. Browsers and frugivores should also produce high levels of PRPs, but grazers may have reduced secretion rates depending on the antiquity of the dietary habit. This hypothesis is consistent with the limited information available on the abundance, type, and distribution of PRPs in mammals. Studies are suggested which would test the functional and evolutionary arguments presented. PMID:24234312

McArthur, C; Sanson, G D; Beal, A M

1995-06-01

315

Two new glycosidic acids, multifidinic acids F and G, of the ether-insoluble resin glycoside (convolvulin) from the seeds of Quamoclit × multifida.  

PubMed

Two new glycosidic acids, multifidinic acids F and G, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction from the seeds of Quamoclit × multifida (syn. Q. sloteri House, Convolvulaceae), a hybrid between Q. pennata and Q. coccinea. The two compounds are the third and fourth examples of bisdesmosides of glycosidic acids having sugar linkages at C-3 of 3,11-dihydroxytetradecanoic acid (ipurolic acid) as well as at C-11. PMID:23271665

Ono, Masateru; Akiyama, Kousuke; Kishida, Makiko; Okawa, Masafumi; Kinjo, Junei; Yoshimitsu, Hitoshi; Miyahara, Kazumoto

2013-10-01

316

Inhibition of hydrogen sulfide, methane, and total gas production and sulfate-reducing bacteria in in vitro swine manure by tannins, with focus on condensed quebracho tannins.  

PubMed

Management practices from large-scale swine production facilities have resulted in the increased collection and storage of manure for off-season fertilization use. Odor and emissions produced during storage have increased the tension among rural neighbors and among urban and rural residents. Production of these compounds from stored manure is the result of microbial activity of the anaerobic bacteria populations during storage. In the current study, the inhibitory effects of condensed quebracho tannins on in vitro swine manure for reduction of microbial activity and reduced production of gaseous emissions, including the toxic odorant hydrogen sulfide produced by sulfate-reducing bacteria (SRB), was examined. Swine manure was collected from a local swine facility, diluted in anaerobic buffer, and mixed with 1 %?w/v fresh feces. This slurry was combined with quebracho tannins, and total gas and hydrogen sulfide production was monitored over time. Aliquots were removed periodically for isolation of DNA to measure the SRB populations using quantitative PCR. Addition of tannins reduced overall gas, hydrogen sulfide, and methane production by greater than 90 % after 7 days of treatment and continued to at least 28 days. SRB population was also significantly decreased by tannin addition. qRT-PCR of 16S rDNA bacteria genes showed that the total bacterial population was also decreased in these incubations. These results indicate that the tannins elicited a collective effect on the bacterial population and also suggest a reduction in the population of methanogenic microorganisms as demonstrated by reduced methane production in these experiments. Such a generalized effect could be extrapolated to a reduction in other odor-associated emissions during manure storage. PMID:23149758

Whitehead, Terence R; Spence, Cheryl; Cotta, Michael A

2013-09-01

317

Dietary crude protein and tannin impact dairy manure chemistry and ammonia emissions from incubated soils.  

PubMed

Excess crude protein (CP) in dairy cow diets is excreted mostly as urea nitrogen (N), which increases ammonia (NH) emissions from dairy farms and heightens human health and environmental concerns. Feeding less CP and more tannin to dairy cows may enhance feed N use and milk production, abate NH emissions, and conserve the fertilizer N value of manure. Lab-scale ventilated chambers were used to evaluate the impacts of CP and tannin feeding on slurry chemistry, NH emissions, and soil inorganic N levels after slurry application to a sandy loam soil and a silt loam soil. Slurry from lactating Holstein dairy cows (Bos taurus) fed two levels of dietary CP (low CP [LCP], 155 g kg; high CP [HCP], 168 g kg) each fed at four levels of dietary tannin extract, a mixture from red quebracho (Schinopsis lorentzii) and chestnut (Castanea sativa) trees (0 tannin [0T]; low tannin [LT], 4.5 g kg; medium tannin [MT], 9.0 g kg; and high tannin [HT], 18.0 g kg) were applied to soil-containing lab-scale chambers, and NH emissions were measured 1, 3, 6, 12, 24, 36, and 48 h after slurry application. Emissions from the HCP slurry were 1.53 to 2.57 times greater ( < 0.05) than from the LCP slurry. At trial's end (48 h), concentrations of inorganic N in soils were greater ( < 0.05) in HCP slurry-amended soils than in LCP slurry-amended soils. Emissions from HT slurry were 28 to 49% lower ( < 0.05) than emissions from 0T slurry, yet these differences did not affect soil inorganic N levels. Emissions from the sandy loam soil were 1.07 to 1.15 times greater ( < 0.05) than from silt loam soil, a result that decreased soil inorganic N in the sandy loam compared with the silt loam soil. Larger-scale and longer-term field trails are needed to ascertain the effectiveness of feeding tannin extracts to dairy cows in abating NH loss from land-applied slurry and the impact of tannin-containing slurry on soil N cycles. PMID:22031559

Powell, J M; Aguerre, M J; Wattiaux, M A

2011-01-01

318

Tannin and tannate from the quebracho tree: an eco-friendly alternative for controlling marine biofouling.  

PubMed

Current antifouling coatings are based on toxic compounds that can be harmful to the natural environment. A promising alternative to these compounds is the use of natural products that are non-toxic, but have antifouling properties. Tannins are natural, water-soluble, complex polyphenolic substances, which precipitate proteins and have anticorrosive and antimicrobial properties. In this study, the effect of quebracho tannin as a probable antifouling pigment in both laboratory and field trials is evaluated. As tannins have high solubility in aqueous media and consequently would leach rapidly, they were precipitated as aluminium tannate, which has an adequate solubility for use as a component in marine paints. In vitro exposure of Balanus amphitrite and Polydora ligni larvae to low concentrations of both quebracho tannin and saturated aluminium tannate solutions produced complete appendage immobilisation. In 28-d field trials of test gels, a significant decrease in micro- and macrofouling density and diversity in relation to the control gel was detected (p < 0.05). This study suggests that natural tannins could be employed as bioactive pigment for new antifouling technologies. PMID:17653926

Pérez, Miriam; García, Mónica; Blustein, Guillermo; Stupak, Mirta

2007-01-01

319

The effect of some tannins on trout erythrocytes exposed to oxidative stress.  

PubMed

In order to gain more knowledge on the role of tannins as antioxidants, their ability to protect (Salmo irideus) erythrocytes against oxidative stress was investigated. Antioxidant activity of different tannins (tannic, gallic and ellagic acid) was evaluated by chemiluminescence (CL) techniques using lucigenin and luminol as chemiluminogenic probes for the superoxide radical generated by the xanthine/xanthine oxidase system and hydrogen peroxide, respectively. The superoxide-scavenging activity of these tannins was shown for all the compounds; however, it is not clear if this is due to their ability of scavenging the superoxide radical or to their inhibitory activity on xanthine oxidase. Tannic and ellagic acid showed a marked effect on the reduction of H2O2-luminol chemiluminescence. The influence of these tannins on the rate of hemolysis in stressed trout erythrocytes was investigated and the results indicate that tannic acid accelerates the hemolytic event while gallic and ellagic acid have no significant effect. The possible protective action of these compounds against oxidative DNA damage was assessed using the comet assay, a rapid and sensitive single-cell gel electrophoresis technique, used to detect primary DNA damage in individual cells. The results here reported show that tannins under study are capable at low concentrations of protecting DNA breakage, while at high concentrations they can be genotoxic. PMID:15364275

Fedeli, Donatella; Berrettini, Marco; Gabryelak, Teresa; Falcioni, Giancarlo

2004-10-10

320

Zoosporicidal activity of polyflavonoid tannin identified in Lannea coromandelica stem bark against phytopathogenic oomycete Aphanomyces cochlioides.  

PubMed

In a survey of nonhost plant secondary metabolites regulating motility and viability of zoospores of the Aphanomyces cochlioides, we found that stem bark extracts of Lannea coromandelica remarkably inhibited motility of zoospores followed by lysis. Bioassay-guided fractionation and chemical characterization of Lannea extracts by MALDI-TOF-MS revealed that the active constituents were angular type polyflavonoid tannins. Commercial polyflavonoid tannins, Quebracho and Mimosa, also showed identical zoosporicidal activity. Against zoospores, the motility-inhibiting and lytic activities were more pronounced in Lannea extracts (MIC 0.1 microg/mL) than in Quebracho (MIC 0.5 microg/mL) and Mimosa (MIC 0.5 microg/mL). Scanning electron microscopic observation visualized that both Lannea and commercial tannins caused lysis of cell membrane followed by fragmentation of cellular materials. Naturally occurring polyflavonoid tannin merits further study as potential zoospore regulating agent or as lead compound. To the best of our knowledge, this is the first report of zoosporicidal activity of natural polyflavonoid tannins against an oomycete phytopathogen. PMID:12405764

Islam, Md Tofazzal; Ito, Toshiaki; Sakasai, Mitsuyoshi; Tahara, Satoshi

2002-11-01

321

Do salivary proline-rich proteins counteract dietary hydrolyzable tannin in laboratory rats?  

PubMed

We hypothesized that dietary hydrolyzable tannins would not act as digestibility reducing substances but would be excreted in the feces if the tannin were ingested by rats producing salivary proline-rich proteins (PRPs). To test that hypothesis we used two groups of Sprague-Dawley rats: tannin-naïve rats that were secreting basal levels of salivary PRPs and tannin-habituated rats that were secreting elevated levels of PRPs. The animals were fed for 10-18 d on diets containing 3% (w/w) purified hydrolyzable tannin [pentagalloyl glucose (PGG)] that was periodically spiked with chemically synthesized, radiolabeled 1,2,3,4,6-penta-O-galloyl-[U-14C]-D-glucopyranose (1 microCi per gram diet). The PGG-habituated rats excreted three times more of the consumed 14C in their feces than did the PGG-naive rats (11.4% for PGG-habituated rats vs. 3.5% for PGG-naïve rats, P < 0.05). The addition of 3% PGG to the diet of the PGG-naïve rats had no significant effect on apparent dry matter or nitrogen digestibility (P > 0.05). However, dry matter digestibility and nitrogen digestibility were significantly decreased by PGG in the diets of the PGG-habituated rats (7 and 25%, P < 0.001, respectively). Production of PRPs increased the amount of PGG excreted intact in the feces but at the cost of diminishing apparent dry matter and nitrogen digestibility. PMID:15586668

Skopec, Michele M; Hagerman, Ann E; Karasov, William H

2004-09-01

322

Effect of plant sterols and tannins on Phytophthora ramorum growth and sporulation.  

PubMed

Elicitin-mediated acquisition of plant sterols is required for growth and sporulation of Phytophthora spp. This study examined the interactions between elicitins, sterols, and tannins. Ground leaf tissue, sterols, and tannin-enriched extracts were obtained from three different plant species (California bay laurel, California black oak, and Oregon white oak) in order to evaluate the effect of differing sterol/tannin contents on Phytophthora ramorum growth. For all three species, high levels of foliage inhibited P. ramorum growth and sporulation, with a steeper concentration dependence for the two oak samples. Phytophthora ramorum growth and sporulation were inhibited by either phytosterols or tannin-enriched extracts. High levels of sterols diminished elicitin gene expression in P. ramorum; whereas the tannin-enriched extract decreased the amount of 'functional' or ELISA-detectable elicitin, but not gene expression. Across all treatment combinations, P. ramorum growth and sporulation correlated strongly with the amount of ELISA-detectable elicitin (R (2)?= 0.791 and 0.961, respectively). PMID:23689874

Stong, Rachel A; Kolodny, Eli; Kelsey, Rick G; González-Hernández, M P; Vivanco, Jorge M; Manter, Daniel K

2013-06-01

323

Widespread tannin intake via stimulants and masticatories, especially guarana, kola nut, betel vine, and accessories.  

PubMed

Tannins are increasingly recognized as dietary carcinogens and as antinutrients interfering with the system's full use of protein. Nevertheless, certain tannin-rich beverages, masticatories, and folk remedies, long utilized in African, Asiatic, Pacific, and Latin American countries, are now appearing in North American sundry shops and grocery stores. These include guarana (Paullinia cupana HBK.) from Brazil, kola nut (Cola nitida Schott & Endl. and C. acuminata Schott & Endl.) from West Africa, and betel nut (Areca catechu L.) from Malaya. The betel nut, or arecanut, has long been associated with oral and esophageal cancer because of its tannin content and the tannin contributed by the highly astringent cutch from Acacia catechu L. and Uncaria gambir Roxb. and the aromatic, astringent 'pan' (leaves of Piper betel L.) chewed with it. In addition to the constant recreational/social ingestion of these plant materials, they are much consumed as aphrodisiacs and medications. Guarana and kola nut enjoy great popularity in their native lands because they are also rich in caffeine, which serves as a stimulant. Research and popular education on the deleterious effects of excessive tannin intake could do much to reduce the heavy burden of early mortality and health care, especially in developing countries. PMID:1417698

Morton, J F

1992-01-01

324

Warning Signs for Cardiac Arrest  

MedlinePLUS

... Pressure Tools & Resources Stroke More Warning Signs for Cardiac Arrest Updated:Oct 5,2011 Cardiac arrest strikes immediately ... content was last reviewed on 07/12/2011." Cardiac Arrest • Home • About Cardiac Arrest • Warning Signs for Cardiac ...

325

Levels of Tannins and Flavonoids in Medicinal Plants: Evaluating Bioprospecting Strategies  

PubMed Central

There are several species of plants used by traditional communities in the Brazilian semiarid. An approach used in the search for natural substances that possess therapeutic value is ethnobotany or ethnopharmacology. Active substances that have phenolic groups in their structure have great pharmacological potential. To establish a quantitative relationship between the species popularly considered to be antimicrobial, antidiabetic, and antidiarrheal, the contents of tannins and flavonoids were determined. The plant selection was based on an ethnobotanical survey conducted in a community located in the municipality of Altinho, northeastern Brazil. For determination of tannin content was utilized the technique of radial diffusion, and for flavonoids, an assay based on the complexation of aluminum chloride. The group of plants with antimicrobial indications showed a higher content of tannins compared to the control groups. The results evidence suggests a possible relationship between these compounds and the observed activity.

Siqueira, Clarissa Fernanda de Queiroz; Cabral, Daniela Lyra Vasconcelos; Peixoto Sobrinho, Tadeu Jose da Silva; de Amorim, Elba Lucia Cavalcanti; de Melo, Joabe Gomes; Araujo, Thiago Antonio de Sousa; de Albuquerque, Ulysses Paulino

2012-01-01

326

Inhibition of constitutive endothelial NO-synthase activity by tannin and quercetin.  

PubMed

The effect of natural polyphenols on three isoforms of NO-synthase was investigated. Among the compounds tested, tannin was the most potent, inhibiting endothelial constitutive NO synthase (eNOS) with an IC50 of 2.2 microM. Other NOS isoforms (i.e. neuronal constitutive NOS and smooth muscle inducible NOS) were also inhibited but at much higher concentrations (selectivity ratio of approx. 20-30). Quercetin was also an effective but less potent inhibitor of eNOS (IC50 = 220 microM). The kinetics of tannin inhibition were investigated to gather information on the mechanism of action. Tannin did not interfere with the interaction of the enzyme with the co-substrates L-arginine and NADPH nor with the cofactor tetrahydrobiopterin. The inhibition level was also independent of free Ca2+ concentration as well as of the presence of high exogenous calmodulin concentrations. PMID:7532940

Chiesi, M; Schwaller, R

1995-02-14

327

Chemical variation of tannins and triterpenes in Brazilian populations of Maytenus ilicifolia Mart. Ex Reiss.  

PubMed

Maytenus ilicifolia and Maytenus aquifolia species are widely used as a cicatrisation agent, an anti-spasmodic, contraceptive, antiulcerogenic, diuretic and analgesic. Considering the importance of these species in popular medicine, this work is focused on the determination of the chemical content of tannins and the triterpenes friedelan-3-one, friedelan-3-ol and friedelin in 15 native populations of Maytenus ilicifolia distributed in the south and mind-west regions of Brazil. Correlation of the concentration of these compounds with the environmental parameters such as average annual temperature, climate, vegetation, geomorphology, latitude and altitude was determined using Pearson's coefficient. Results showed that average annual temperature and climate have significant effect on tannin content at a 95% confidence level. The highest tannin concentration was found in Ponta Porã population, and for the triterpenes investigated, a significant correlation between their concentrations with the environmental variables studied was not verified. PMID:19675936

Mossi, A J; Mazutti, M; Paroul, N; Corazza, M L; Dariva, C; Cansian, R L; Oliveira, J V

2009-05-01

328

Gallic acid and hydrolysable tannins are formed in birch leaves from an intermediate compound of the shikimate pathway  

Microsoft Academic Search

Gallic acid is the starting material for hydrolysable tannin synthesis, but the mechanism of its formation in higher plants has not been known. To elucidate the pathway of gallic acid synthesis in the leaves of mountain birch (Betula pubescens ssp. czerepanovii), we studied the effects of glyphosate (N-[phosphonomethyl]-glycine) on the levels of individual hydrolysable tannins. Glyphosate is known to block

Vladimir Ossipov; Juha-Pekka Salminen; Svetlana Ossipova; Erkki Haukioja; Kalevi Pihlaja

2003-01-01

329

Direct anthelmintic effects of condensed tannins from diverse plant sources against Ascaris suum.  

PubMed

Ascaris suum is one of the most prevalent nematode parasites in pigs and causes significant economic losses, and also serves as a good model for A. lumbricoides, the large roundworm of humans that is ubiquitous in developing countries and causes malnutrition, stunted growth and compromises immunity to other pathogens. New treatment options for Ascaris infections are urgently needed, to reduce reliance on the limited number of synthetic anthelmintic drugs. In areas where Ascaris infections are common, ethno-pharmacological practices such as treatment with natural plant extracts are still widely employed. However, scientific validation of these practices and identification of the active compounds are lacking, although observed effects are often ascribed to plant secondary metabolites such as tannins. Here, we extracted, purified and characterised a wide range of condensed tannins from diverse plant sources and investigated anthelmintic effects against A. suum in vitro. We show that condensed tannins can have potent, direct anthelmintic effects against A. suum, as evidenced by reduced migratory ability of newly hatched third-stage larvae and reduced motility and survival of fourth-stage larvae recovered from pigs. Transmission electron microscopy showed that CT caused significant damage to the cuticle and digestive tissues of the larvae. Furthermore, we provide evidence that the strength of the anthelmintic effect is related to the polymer size of the tannin molecule. Moreover, the identity of the monomeric structural units of tannin polymers may also have an influence as gallocatechin and epigallocatechin monomers exerted significant anthelmintic activity whereas catechin and epicatechin monomers did not. Therefore, our results clearly document direct anthelmintic effects of condensed tannins against Ascaris and encourage further in vivo investigation to determine optimal strategies for the use of these plant compounds for the prevention and/or treatment of ascariosis. PMID:24810761

Williams, Andrew R; Fryganas, Christos; Ramsay, Aina; Mueller-Harvey, Irene; Thamsborg, Stig M

2014-01-01

330

Direct Anthelmintic Effects of Condensed Tannins from Diverse Plant Sources against Ascaris suum  

PubMed Central

Ascaris suum is one of the most prevalent nematode parasites in pigs and causes significant economic losses, and also serves as a good model for A. lumbricoides, the large roundworm of humans that is ubiquitous in developing countries and causes malnutrition, stunted growth and compromises immunity to other pathogens. New treatment options for Ascaris infections are urgently needed, to reduce reliance on the limited number of synthetic anthelmintic drugs. In areas where Ascaris infections are common, ethno-pharmacological practices such as treatment with natural plant extracts are still widely employed. However, scientific validation of these practices and identification of the active compounds are lacking, although observed effects are often ascribed to plant secondary metabolites such as tannins. Here, we extracted, purified and characterised a wide range of condensed tannins from diverse plant sources and investigated anthelmintic effects against A. suum in vitro. We show that condensed tannins can have potent, direct anthelmintic effects against A. suum, as evidenced by reduced migratory ability of newly hatched third-stage larvae and reduced motility and survival of fourth-stage larvae recovered from pigs. Transmission electron microscopy showed that CT caused significant damage to the cuticle and digestive tissues of the larvae. Furthermore, we provide evidence that the strength of the anthelmintic effect is related to the polymer size of the tannin molecule. Moreover, the identity of the monomeric structural units of tannin polymers may also have an influence as gallocatechin and epigallocatechin monomers exerted significant anthelmintic activity whereas catechin and epicatechin monomers did not. Therefore, our results clearly document direct anthelmintic effects of condensed tannins against Ascaris and encourage further in vivo investigation to determine optimal strategies for the use of these plant compounds for the prevention and/or treatment of ascariosis.

Williams, Andrew R.; Fryganas, Christos; Ramsay, Aina; Mueller-Harvey, Irene; Thamsborg, Stig M.

2014-01-01

331

Production of Proline-Rich Proteins by the Parotid Glands of Rats Is Enhanced by Feeding Diets Containing Tannins from Faba Beans (Vicia faba L.)1'2  

Microsoft Academic Search

Feeding a casein-based diet with either 400 g\\/kg of tannin-containing faba bean hulls (Vicia faba L.) (1.41% condensed tannins) or 60 g\\/kg of a tannin-rich hull extract of faba beans (1.99% condensed tannins) to rats over a period of 7 d resulted in a 2.6 and 1.5 fold increase in weight of the parotid glands, respec tively, (P < 0.05)

ALFONS J. M. JANSMAN; ANDREW A. FRÃ-HLICH; RONALD R. MARQÜARDT

332

Extracellular versus intracellular digoxin action on bovine myocardium, using a digoxin antibody and intracellular glycoside application.  

PubMed Central

1. The actions of externally and internally applied digoxin in heart ventricular muscle have been compared. 2. External application of digoxin (5 x 10(-8)--10(-7) M) had an inotropic effect, a steady level of twitch tension being reached at the end of about 3 hr. 3. Addition of an anti-digoxin antibody to the bathing solution prevented or reversed the digoxin effect, depending on the time of application. 4. The efflux of the antibody-[3H]digoxin-complex could be fitted by a single exponential with a half-time of 18 min. 5. In the absence of antibody, [3H]digoxin washout was two-compartmental with half-times of 4 and 72 min respectively. It is thought that the fast process signifies efflux from the extracellular space while the slow process reflects the washout of initially membrane bound glycoside. 6. When digoxin was applied by a cut end method, there was no effect on contractile strength. 7. The profile of radioactivity several hours following exposure to [3H]digoxin clearly indicated movement from cell to cell, the concentration of [3H]digoxin being above 10(-7) M in half the preparation at the end of 6 hr. Longitudinal diffusivity averaged 8.6 x 10(-8) cm-2 sec-1. 8. We conclude that digoxin has an inotropic effect when reaching the surface membrane of cardiac cells from the outside but is ineffective when applied from the inside.

Hess, P; Muller, P

1982-01-01

333

Tetrahydroisoquinoline-monoterpene and iridoid glycosides from Alangium lamarckii.  

PubMed

From the water soluble fraction of the dried fruits of Alangium lamrckii, four tetrahydroisoquinoline-monoterpene glycosides, 6-O-methyl-N-deacetylisoipecosidic acid, 7-O-methyl-N-deacetylisoipecosidic acid, 6,7-di-O-methyl-N-deacetylisoipecosidic acid and 6"-O-alpha-D-glucopyranosyl-6-O-methyl-N-deacetylisoipecosidic acid, and an iridoid glycoside, 6'-O-alpha-D-glucopyranosylloganic acid, were isolated, together with six known compounds. The structures of the previously unknown compounds were determined by spectroscopic and chemical means. The significance of these glucosides in the biogenesis of Alangium alkaloids is discussed; 6-O-methyl-N-deacetylisoipecosidic acid was also chemically converted into 10-O-demethylprotoemetine and dihydroisoalangine. PMID:11281140

Itoh, A; Tanahashi, T; Tabata, M; Shikata, M; Kakite, M; Nagai, M; Nagakura, N

2001-03-01

334

Gilvocarcin HE: a new polyketide glycoside from Streptomyces sp.  

PubMed

A new antimicrobial polyketide glycoside (1) and three known compounds, gilvocarcins H (2), V (3) and M (4) were isolated from the ethyl acetate extract of Streptomyces sp. QD01-2. The structure of (1) was established by spectroscopic analysis, X-ray single crystal diffraction and CD spectra. The new compound (1) showed potent antimicrobial activities against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Candida albicans, with MIC values of 0.5-5.0??M. Compound (1) also showed weak cytotoxicity against the MCF-7, K562 and P388 cell lines, with IC(50) values of 36, 39 and 45??M, respectively. The results showed that the vinyl side chain helps to increase the cytotoxicity and antimicrobial activities of gilvocarcin-type glycosides. In addition, the NMR data of gilvocarcin H (2) were also reported for the first time. PMID:22854339

Hou, Jiabo; Liu, Peipei; Qu, Haijun; Fu, Peng; Wang, Yi; Wang, Zhiying; Li, Ye; Teng, Xiancun; Zhu, Weiming

2012-10-01

335

Malonylated flavonol glycosides from the petals of Clitoria ternatea.  

PubMed

Three flavonol glycosides, kaempferol 3-O-(2"-O-alpha-rhamnosyl-6"-O-malonyl)-beta-glucoside, quercetin 3-O-(2"-O-alpha-rhamnosyl-6"-O-malonyl)-beta-glucoside, and myricetin 3-O-(2",6"-di-O-alpha-rhamnosyl)-beta-glucoside were isolated from the petals of Clitoria ternatea cv. Double Blue, together with eleven known flavonol glycosides. Their structures were identified using UV, MS, and NMR spectroscopy. They were characterized as kaempferol and quercetin 3-(2(G)- rhamnosylrutinoside)s, kaempferol, quercetin, and myricetin 3-neohesperidosides, 3-rutinosides, and 3-glucosides in the same tissue. In addition, the presence of myricetin 3-O-(2"-O-alpha-rhamnosyl-6"-O-malonyl)-beta-glucoside was inferred from LC/MS/MS data for crude petal extracts. The flavonol compounds identified in the petals of C. ternatea differed from those reported in previous studies. PMID:12482461

Kazuma, Kohei; Noda, Naonobu; Suzuki, Masahiko

2003-01-01

336

Coumarins of Matricaria chamomilla L.: aglycones and glycosides.  

PubMed

The identity and quantity of coumarin-like compounds in leaves and anthodia of Matricaria chamomilla L. were studied by LC-DAD and NMR. So far, two monosubstituted coumarins, herniarin and umbelliferone, and two herniarin precursors were identified therein. In this paper, two other coumarin glycosides and one aglycone were confirmed. Skimmin (umbelliferone-7-O-?-d-glucoside), daphnin (daphnetin-7-O-?-d-glucoside) and daphnetin (7,8-dihydroxycoumarin) were found for the first time in diploid and tetraploid leaves and anthodia of M. chamomilla L. Daphnetin is known as a strong sensitizer, so this compound and its glycosidic derivative can contribute to the allergic potential of chamomile. Commercial chamomile preparations were tested for their presence. PMID:23768326

Petru?ová-Poracká, Veronika; Rep?ák, Miroslav; Vilková, Mária; Imrich, Ján

2013-11-01

337

Two spirostan steroid glycoside fatty esters from Dioscorea cayenensis.  

PubMed

Two new fatty acid-spirostan steroid glycoside esters, progenin III palmitate (1) and progenin III linoleate (2), were isolated from the MeOH extract of Dioscorea cayenensis rhizomes. The extract also yielded seven previously known spirostan and furostan steroid glycosides (3-9). The structures of the new compounds were established as (25R)-spirost-5-en-3beta-yl O-alpha-L-rhamnopyranosyl-(1 --> 2)-[6-O-palmitoyl]-O-beta-D-glucopyranoside (1) and (25R)-spirost-5-en-3beta-yl O-alpha-L-rhamnopyranosyl-(1 --> 2)-[6-O-linoleoyl]-O-beta-D-glucopyranoside (2) by chemical and spectroscopic methods, including 1D and 2D NMR. The known compounds were identified as progenin III (3), dioscin (4), deltonin (5), asperin (6), gracillin (7), protodioscin (8)], and methyl protodioscin (9). PMID:23678801

Ali, Zulfiqar; Smillie, Troy J; Khan, Ikhlas A

2013-03-01

338

Nano-porous solid-state photovoltaic cell sensitized with tannin  

NASA Astrophysics Data System (ADS)

Tannin and related polyphenolic substances strongly surface chelate with 0268-1242/13/1/021/img1 sensitizing nano-porous films of 0268-1242/13/1/021/img1 to the visible spectrum. The photovoltaic cell nano-porous n-0268-1242/13/1/021/img3-CuI generates highly stable photovoltages. The result is explained as the effectiveness of the 0268-1242/13/1/021/img4-tannin complex on the surface of 0268-1242/13/1/021/img1 in preventing short-circuiting across the 0268-1242/13/1/021/img1/CuI barrier.

Tennakone, K.; Kumara, G. R. R. A.; Wijayantha, K. G. U.; Kottegoda, I. R. M.; Perera, V. P. S.; Aponsu, G. M. L. P.

1998-01-01

339

Block copolymers as low-VOC coatings for wood: characterization and tannin bleed resistance  

Microsoft Academic Search

Replacement of solvent-borne primers with low-VOC water-based coatings has created the problem of tannin bleed for cedar siding finishers. Three amphiphilic block copolymers, poly(styrene-b-acrylic acid) (PS-PAA), poly(styrene-b-ethylene oxide) (PS-PEO), and poly(styrene-b-methacrylic acid) (PS-PMAA), were investigated as potential water-based coating components that could create a hydrophobic barrier to block tannin extraction. Resistance to extractive bleed was determined by measuring topcoat color

Abigail S. Kimerling; Surita R. Bhatia

2004-01-01

340

New monocyclic monoterpenoid glycoside from Mentha haplocalyx Briq.  

PubMed

Two new monocyclic monoterpenoid glycosides, rel-(1R,2S,3R,4R) p-menthane-1,2,3-triol 3-O-?-D-glucopyranoside (1) and rel- (1S,2R,3S) terpinolene-1,2,3-triol 3-O-?-D-glucopyranoside (2) were isolated from aqueous acetone extract of the aerial parts of Mentha haplocalyx Briq.. Their structures were elucidated through spectral analysis using MS and NMR spectrometers. PMID:22559003

She, Gai-Mei; Xu, Chao; Liu, Bin

2012-01-01

341

Hydrolysis of black soybean isoflavone glycosides by Bacillus subtilis natto  

Microsoft Academic Search

Hydrolysis of isoflavone glycosides by Bacillus subtilis natto NTU-18 in black soymilk is reported. At the concentration of 3–5% (w\\/v), black soymilk in flask cultures, the isoflavones, daidzin, and genistin were highly deglycosylated within 24 h. Deglycosylation of isoflavones was further carried out in a 7-l fermenter with 5% black soymilk. During the fermentation, viable cells increased from 103 to 109 CFU

Lun-Cheng Kuo; Wei-Yi Cheng; Ren-Yu Wu; Ching-Jang Huang; Kung-Ta Lee

2006-01-01

342

Phenolic glycosides from the leaves of Alangium platanifolium var. platanifolium.  

PubMed

Chemical investigation of Alangium platanifolium var. platanifolium has resulted in the isolation of nine phenolic glycosides that were identified by means of 1D and 2D NMR experiments. Among them, catechol and salicinol O- and 1-O-beta-D-(6-O-beta-D-apiofuranosyl)glucopyranosides, respectively 1 and 2, and two compounds characterized as adducts of 2, 6-dihydroxybenzoic acid with salicin (plataplatanoside, 3) and 4-hydroxysalicin (4-hydroxyalangifolioside, 4) were determined structurally as new compounds. PMID:11076566

Tamaki, A; Ide, T; Otsuka, H

2000-10-01

343

Phenylpropanoid glycosides from the leaves of Paulownia coreana.  

PubMed

Study on the water soluble fraction from the leaves of Paulownia coreana led to the isolation of verbascoside (1), isoverbascoside (2), campneoside II (3), and a new phenylpropanoid glycoside, (R,S)-7-hydroxy-7-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl(1 --> 3)-beta-d-(6-O-caffeoyl)-glucopyranoside (4). The structures of these compounds were established on the basis of spectroscopic evidence. PMID:18266154

Kim, Jin-Kyu; Si, Chuan-Ling; Bae, Young-Soo

2008-02-15

344

New monocyclic monoterpenoid glycoside from Mentha haplocalyx Briq.  

PubMed Central

Two new monocyclic monoterpenoid glycosides, rel-(1R,2S,3R,4R) p-menthane-1,2,3-triol 3-O-?-D-glucopyranoside (1) and rel- (1S,2R,3S) terpinolene-1,2,3-triol 3-O-?-D-glucopyranoside (2) were isolated from aqueous acetone extract of the aerial parts of Mentha haplocalyx Briq.. Their structures were elucidated through spectral analysis using MS and NMR spectrometers.

2012-01-01

345

Cucurbitane glycosides from unripe fruits of Siraitia grosvenori.  

PubMed

Studies on the constituents of the unripe fruits of Siraitia grosvenori led to the isolation of three new cucurbitane triterpene glycosides, 11-oxomogroside III (10), 11-dehydroxymogroside III (11), and 11-oxomogroside IV A (12). Their structures were determined on the basis of detailed analyses of 1D, 2D-NMR spectroscopic methods. All of the compounds isolated from the unripe fruits of S. grosvenori were tested for cytotoxic activities against tumor cells, HCT-116 and SMMC-7721. PMID:17603208

Li, Dianpeng; Ikeda, Tsuyoshi; Nohara, Toshihiro; Liu, Jinlei; Wen, Yongxin; Sakamoto, Tatsunori; Nonaka, Gen-Ichiro

2007-07-01

346

A Glycosidation Reaction Employing Montmorillonite K-10 as Catalyst  

NASA Astrophysics Data System (ADS)

The large number of biology majors and prehealth students enrolled in Organic Chemistry makes it desirable to have laboratories that involve biologically interesting molecules. Although many laboratory manuals contain sections on carbohydrate chemistry, the experiments are typically limited to esterification or hydrolysis reactions. A recent publication (Toshima, K.; Ishizuka, T.; Matsuo, G.; Nakata, M. Synlett. 1995, 306. ) on the glycosidation of glycals offered a different possibility.

Bedell, Brooke L.; Crouch, R. David; Holden, Michael S.; Martinson, Heidi E.

1996-11-01

347

A new triterpene glycoside from the roots of Symphytum officinale.  

PubMed

Chemical investigation of the EtOH-soluble portion of Symphytum officinale roots has resulted in the isolation of a new pentacyclic triterpene glycoside of oleanolic acid. Its structure was elucidated by spectroscopic studies, including 2D nmr, and chemical evidences as 3-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->4)-alpha-L -arabinopyranosyl]-oleanolic acid [1]. PMID:8482944

Ahmad, V U; Noorwala, M; Mohammad, F V; Sener, B

1993-03-01

348

Relative antioxidant activity of soybean isoflavones and their glycosides  

Microsoft Academic Search

The present study compared the antioxidant potency of genistein and daidzein with their corresponding glycosides isolated from soybean seeds. The antioxidant activity was assessed using three methods, namely human low-density lipoprotein (LDL) oxidation, the ferric reducing-antioxidant power (FRAP) and the anti-DPPH free radical assays. It was found that soybean was rich in genistein and daidzein but they were present mainly

Chung Hung Lee; Lin Yang; Jin Ze Xu; Sai Ying Venus Yeung; Yu Huang; Zhen-Yu Chen

2005-01-01

349

A novel bioactive flavonol glycoside from Teramnus labialis spreng.  

PubMed

A novel biologically active flavonol glycoside (1), C26H28O17, m.p. 216-217 degrees C, was isolated from the chloroform soluble fraction of the ethanol extract of the stems of Teramnus labialis. Its structure was characterized as 3,5,7,3',4',5'-hexahydroxyflavone-3-O-beta-D-glucopyranosyl(1-->3)-O-alpha-L-arabinopyranoside by spectral analysis. The chloroform extract of compound (1) showed antibacterial and antifungal activities. PMID:15595611

Yadava, R N; Jain, Shivani

2004-12-01

350

Two acylated diarylheptanoid glycosides from red alder bark  

PubMed

Two novel acylated diarylheptanoid glycosides, oregonosides A and B (3, 4, respectively), were isolated from red alder bark and their structures established by spectrometric techniques. The compounds were identified as (5S)-1,7-bis(3, 4-dihydroxyphenyl)-5-O-(6-O-benzoyl-beta-D-glucopyranosyl)-heptan-3-o ne and (5S)-1,7-bis(3, 4-dihydroxyphenyl)-5-O-(6-O-vanilloyl-beta-D-glucopyranosyl)-heptan-3 -one. PMID:9784172

Gonzalez-Laredo; Helm; Chen; Karchesy

1998-10-01

351

A new C 21-steroidal glycoside from Cynanchum stauntonii  

Microsoft Academic Search

A new C21-steroidal glycoside with two known compounds were isolated from the root of Cynanchum Stauntonii. Based on the spectral analysis, including MS, 1H NMR, 13C NMR, DEPT, 1H–1H COSY, 13C–1H COSY, HMQC and HMBC, their chemical structures were determinated as glaucogenin-C 3-O-?-l-cymaropyranosyl-(1?4)-?-d-digitoxopyranosyl-(1?4)-?-d-canaropyranoside (1), stigmasterol (2) and ursolic acid (3).

Mei Hong Fu; Zhu Ju Wang; Hong Jun Yang; Mayila Maimai; Jing Fang; Li Ying Tang; Lan Yang

2007-01-01

352

Inhibitory effects of Thai plants ?-glycosides on Trichomonas vaginalis  

Microsoft Academic Search

Trichomoniasis is now an important health problem in developing countries. Although metronidazole has so far been widely used\\u000a to treat this disease, the prevalence of metronidazole-resistant protozoa and unpleasant adverse effects have been found.\\u000a In this study, natural products purified from Thai plants were, therefore, investigated for their effectiveness against Trichomonas vaginalis. The minimal inhibitory concentrations for all ?-glycosides against

Dumrongkiet Arthan; Somphong Sithiprom; Kanthinich Thima; Chutima Limmatvatirat; Porntip Chavalitshewinkoon-Petmitr; Jisnuson Svasti

2008-01-01

353

Three new homoisoflavanone glycosides from the bulbs of Ornithogalum caudatum.  

PubMed

Phytochemical examination of Ornithogalum caudatum led to the isolation of three new homoisoflavanone glycosides. Their structures were elucidated, on the basis of the spectroscopic data and chemical evidence and by comparing them with those of known compounds, as (-)-7-O-methyleucomol 5-O-beta-D-glucopyranoside (1), (-)-7-O-methyleucomol 5-O-beta-rutinoside (2), and (-)-7-O-methyleucomol 5-O-beta-neohesperidoside (3), respectively. PMID:11858761

Tang, Yuping; Yu, Biao; Hu, Jie; Wu, Tao; Hui, Hongzheng

2002-02-01

354

Toxicological evaluation of the isoflavone puerarin and its glycosides  

Microsoft Academic Search

Puerarin, an isoflavone derived from kudzu roots, has strong biological activities. However, its bioavailability in vivo is\\u000a often limited by its insolubility. A novel transglycosylase increases the solubility of puerarin >100-fold, by converting\\u000a it to puerarin glycosides. Since over-consumption of an isoflavone might have toxic effects, therefore, we investigated the\\u000a potential antimutagenic activity, bone marrow micronucleus test, and a 28-day

Hyuk Jin Chung; Mi Ja Chung; Soung-Jin Houng; Jungae Jeun; Dong-Keon Kweon; Chung Hyo Choi; Jong-Tae Park; Kwan-Hwa Park; Sung-Joon Lee

2009-01-01

355

Hydrolysis of grape glycosides by enological yeast ?-glucosidases  

Microsoft Academic Search

Three enological yeast strains, belonging to the speciesDebaryomyces hansenii, Debaryomyces polymorphus, andSaccharomyces cerevisiae, characterized by an exocellular ?-glucosidase activity, were examined for their ability to hydrolize a glycosidic extract from grape juice. The enzymatic preparations (culture supernant fluid) of the different yeasts released different amounts of terpenols such as linalol, ?-terpineol, geraniol, nerol, citronellol and benzyl and 2-phenylethyl alcohol. The

I. Rosi; P. Domizio; M. Vinella; M. Salicone

1995-01-01

356

Oleanane and taraxerane glycosides from the roots of Gomphrena macrocephala.  

PubMed

Phytochemical screening of the roots of Gomphrena macrocephala, with particular attention to its triterpene glycoside constituents, has resulted in the isolation of two new oleanane glycosides (1 and 2) and a new taraxerane glycoside (3). The structures of 1-3 were determined as 11alpha,12alpha-epoxy-3beta-[(O-beta-D-glucuronopyranosyl)oxy]olean-28,13-olide (1), 11alpha,12alpha-epoxy-3beta-[(O-beta-D-galactopyranosyl-(1-->3)-O-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl)-oxy]olean-28,13-olide (2), and 11alpha,12alpha-epoxy-3beta-[(O-beta-D-glucuronopyranosyl)oxy]taraxer-14-en-28-oic acid beta-D-glucopyranosyl ester (3), respectively, on the basis of their spectroscopic data and the results of hydrolysis. The aglycones (1a and 3a) of 1-3 with an epoxy group showed cytotoxic activity against HSC-2 human oral squamous carcinoma cells. PMID:17125230

Kuroda, Minpei; Aoshima, Taku; Haraguchi, Mitsue; Young, Maria Claudia Marx; Sakagami, Hiroshi; Mimaki, Yoshihiro

2006-11-01

357

Glycosidically bound flavor compounds of cape gooseberry (Physalis peruviana L.).  

PubMed

The bound volatile fraction of cape gooseberry (Physalis peruviana L.) fruit harvested in Colombia has been examined by HRGC and HRGC-MS after enzymatic hydrolysis using a nonselective pectinase (Rohapect D5L). Forty bound volatiles could be identified, with 21 of them being reported for the first time in cape gooseberry. After preparative isolation of the glycosidic precursors on XAD-2 resin, purification by multilayer coil countercurrent chromatography and HPLC of the peracetylated glycosides were carried out. Structure elucidation by NMR, ESI-MS/MS, and optical rotation enabled the identification of (1S,2S)-1-phenylpropane-1,2-diol 2-O-beta-D-glucopyranoside (1) and p-menth-4(8)-ene-1,2-diol 1-O-alpha-L-arabinopyranosyl-(1-6)-beta-D-glucopyranoside (2). Both glycosides have been identified for the first time in nature. They could be considered as immediate precursors of 1-phenylpropane-1,2-diol and p-menth-4(8)-ene-1,2-diol, typical volatiles found in the fruit of cape gooseberry. PMID:11308344

Mayorga, H; Knapp, H; Winterhalter, P; Duque, C

2001-04-01

358

Naturally occurring phenylethanoid glycosides: potential leads for new therapeutics.  

PubMed

Natural products have long been regarded as excellent sources for drug discovery given their structure diversity and wide variety of biological activities. Phenylethanoid glycosides are naturally occurring compounds of plant origin and are structurally characterized with a hydroxyphenylethyl moiety to which a glucopyranose is linked through a glycosidic bond. To date several hundred compounds of this type have been isolated from medicinal plants and further pharmacological studies in vitro or in vivo have shown that these compounds possess a broad array of biological activities including antibacterial, antitumor, antiviral, anti-inflammatory, neuro-protective, antioxidant, hepatoprotective, immunomodulatory, and tyrosinase inhibitory actions. Given their extensive activity profile, structure-activity relationships analyses of these compounds have been performed in a number of studies to reveal potential leads for future drug design. This article will summarize the major developments in phenylethanoid glycosides-based research in the past decade. The progresses made in phytochemistry and biological activity studies of these compounds will be reviewed. Particular attention will be given to the novel structures identified to date and the prominent therapeutic values associated with these molecules. PMID:18855681

Fu, Guangmiao; Pang, Haihong; Wong, Yung H

2008-01-01

359

The role of condensed tannins in the nutritional value of Lotus pedunculatus for sheep. 1. Voluntary intake.  

PubMed

Voluntary intake was determined with vegetative Lotus pedunculatus cut and fed fresh to growing sheep of 42-46 kg live weight. Effects attributable to condensed tannins were assessed by growing the plant under high and low levels of soil fertility, inducing low and high concentrations of tannin (Expt 1), or by binding the tannins through spraying the herbage with polyethylene glycol (molecular weight 3350, PEG; Expt 2). Primary-growth lotus was used in Expt 1 and secondary-growth lotus in Expt 2. Concentrations of total and free condensed tannin were determined in fresh lotus, free tanning being defined as that not bound by mascerates of the plant. In Expt 1 the herbages fed contained respectively 46 and 106 g total condensed tannin/kg dry matter (DM) and 3 and 14 g free condensed tannin/kg DM. Mean metabolizable energy (ME) intakes were 0.89 and 0.77 MJ/kg live weight0 .75 per d (P less than 0.05) respectively. The lotus used in Expt 2 contained 63 and 5 g total reactive condensed tannin and free condensed tannin/kg DM respectively. After spraying with PEG at 2.4 g/g total condensed tannin, these values were reduced to 7 and 0.5 g/kg DM respectively. PEG addition increased apparent digestibility (proportion of each nutrient ingested) of cellulose, hemicellulose and nitrogen by 0.05, 0.08 and 0.26, and increased ME intake from 0.48 to 0.69 MJ/kg live weight0 .75 per d. It was concluded that high concentrations of condensed tannins depressed ME intake, due to depressions in both the voluntary intake and digestion of organic matter.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6722089

Barry, T N; Duncan, S J

1984-05-01

360

Antioxidants in the midgut fluids of a tannin-tolerant and a tannin-sensitive caterpillar: effects of seasonal changes in tree leaves.  

PubMed

The seasonal decline in foliar nutritional quality in deciduous trees also effects the availability of essential micronutrients, such as ascorbate and alpha-tocopherol, to herbivorous insects. This study first examined whether there are consistent patterns of seasonal change in antioxidant concentrations in deciduous tree leaves. Alpha-tocopherol concentrations increased substantially through time in late summer in sugar maple (Acer saccharum), red oak (Quercus rubra), and trembling aspen (Populus tremuloides). However, seasonal change in the concentrations of other antioxidants differed between each species: P. tremuloides had higher levels of ascorbate and glutathione in the spring, Q. rubra had higher levels of glutathione but lower levels of ascorbate in the spring, and A. saccharum had lower levels of both ascorbate and glutathione in the spring. To test the hypothesis that tannin-tolerant caterpillars maintain higher concentrations of antioxidants in their midgut fluids than do tannin-sensitive species, we measured antioxidants in Orgyia leucostigma (a spring- and summer-feeding, tannin-tolerant species) and Malacosoma disstria (a spring-feeding, tannin-sensitive species) that were fed tree leaves in the spring and summer. The midgut fluids of O. leucostigma larvae generally had higher concentrations of antioxidants in the summer than did those of M. disstria, and were significantly higher overall. The results of this study are consistent with the hypothesis that higher concentrations of antioxidants form an important component of the defenses of herbivores that feed on mature, phenol-rich tree leaves. Some limitations of the interpretation of total antioxidant capacity are also discussed. PMID:12857024

Barbehenn, Raymond V; Walker, Ann C; Uddin, Farhan

2003-05-01

361

Origins of Cardiac Fibroblasts  

PubMed Central

Cardiac fibroblasts play a critical role in maintenance of normal cardiac function. They are indispensable for damage control and tissue remodeling on myocardial injury and principal mediators of pathological cardiac remodeling and fibrosis. Despite their manyfold functions, cardiac fibroblasts remain poorly characterized in molecular terms. Evidence is evolving that cardiac fibroblasts are a heterogeneous population and likely derive from various distinct tissue niches in health and disease. Here, we review our emerging understanding of where cardiac fibroblasts come from, as well as how we can possibly use this knowledge to develop novel therapies for cardiac fibrosis.

Zeisberg, Elisabeth M.; Kalluri, Raghu

2011-01-01

362

Taxifolin Glycoside Blocks Human ether-a-go-go Related Gene K+ Channels  

PubMed Central

Taxifolin glycoside is a new drug candidate for the treatment of atopic dermatitis (AD). Many drugs cause side effects such as long QT syndrome by blocking the human ether-a-go-go related gene (hERG) K+ channels. To determine whether taxifolin glycoside would block hERG K+ channels, we recorded hERG K+ currents using a whole-cell patch clamp technique. We found that taxifolin glycoside directly blocked hERG K+ current in a concentration-dependent manner (EC50=9.6±0.7 µM). The activation curve of hERG K+ channels was negatively shifted by taxifolin glycoside. In addition, taxifolin glycoside accelerated the activation time constant and reduced the onset of the inactivation time constant. These results suggest that taxifolin glycoside blocks hERG K+ channels that function by facilitating activation and inactivation process.

Yun, Jihyun; Bae, Hyemi; Choi, Sun Eun; Kim, Jung-Ha; Choi, Young Wook; Lim, Inja; Lee, Chung Soo; Lee, Min Won; Ko, Jae-Hong; Seo, Seong Jun

2013-01-01

363

Annotation and comparative analysis of the glycoside hydrolase genes in Brachypodium distachyon  

PubMed Central

Background Glycoside hydrolases cleave the bond between a carbohydrate and another carbohydrate, a protein, lipid or other moiety. Genes encoding glycoside hydrolases are found in a wide range of organisms, from archea to animals, and are relatively abundant in plant genomes. In plants, these enzymes are involved in diverse processes, including starch metabolism, defense, and cell-wall remodeling. Glycoside hydrolase genes have been previously cataloged for Oryza sativa (rice), the model dicotyledonous plant Arabidopsis thaliana, and the fast-growing tree Populus trichocarpa (poplar). To improve our understanding of glycoside hydrolases in plants generally and in grasses specifically, we annotated the glycoside hydrolase genes in the grasses Brachypodium distachyon (an emerging monocotyledonous model) and Sorghum bicolor (sorghum). We then compared the glycoside hydrolases across species, at the levels of the whole genome and individual glycoside hydrolase families. Results We identified 356 glycoside hydrolase genes in Brachypodium and 404 in sorghum. The corresponding proteins fell into the same 34 families that are represented in rice, Arabidopsis, and poplar, helping to define a glycoside hydrolase family profile which may be common to flowering plants. For several glycoside hydrolase familes (GH5, GH13, GH18, GH19, GH28, and GH51), we present a detailed literature review together with an examination of the family structures. This analysis of individual families revealed both similarities and distinctions between monocots and eudicots, as well as between species. Shared evolutionary histories appear to be modified by lineage-specific expansions or deletions. Within GH families, the Brachypodium and sorghum proteins generally cluster with those from other monocots. Conclusions This work provides the foundation for further comparative and functional analyses of plant glycoside hydrolases. Defining the Brachypodium glycoside hydrolases sets the stage for Brachypodium to be a grass model for investigations of these enzymes and their diverse roles in planta. Insights gained from Brachypodium will inform translational research studies, with applications for the improvement of cereal crops and bioenergy grasses.

2010-01-01

364

Astonishing diversity of natural surfactants: 6. Biologically active marine and terrestrial alkaloid glycosides  

Microsoft Academic Search

This review article presents 209 alkaloid glycosides isolated and identified from plants, microorganisms, and marine invertebrates\\u000a that demonstrate different biological activities. They are of great interest, especially for the medicinal and\\/or pharmaceutical\\u000a industries. These biologically active glycosides have good potential for future chemical preparation of compounds useful as\\u000a antioxidants, anticancer, antimicrobial, and antibacterial agents. These glycosidic compounds have been subdivided

Valery M. Dembitsky

2005-01-01

365

Effects of the isoflavone puerarin and its glycosides on melanogenesis in B16 melanocytes  

Microsoft Academic Search

We investigated the effects of puerarin (8-C-glucosyl-7,4?-dihydroxy isoflavone), an isoflavone found in Kudzu roots (Pueraria lobata), and its glycosides (enzymatically synthesised, water-soluble derivatives of puerarin) on melanogenesis in vitro. Puerarin\\u000a and its glycosides reduced mushroom tyrosinase activity by 88 and 67% at 4.8 mM, respectively, in a concentration-dependent\\u000a manner. The puerarin glycosides were less effective than puerarin at the same concentration

Young-Mi Choi; Hee-jin Jun; Kevin Dawson; Raymond L. Rodriguez; Mi Ran Roh; Jungae Jun; Chung-Hyo Choi; Jae-Hoon Shim; ChoongHwan Lee; Sang Jun Lee; Kwan-Hwa Park; Sung-Joon Lee

2010-01-01

366

Annotation and comparative analysis of the glycoside hydrolase genes in Brachypodium distachyon  

SciTech Connect

Background Glycoside hydrolases cleave the bond between a carbohydrate and another carbohydrate, a protein, lipid or other moiety. Genes encoding glycoside hydrolases are found in a wide range of organisms, from archea to animals, and are relatively abundant in plant genomes. In plants, these enzymes are involved in diverse processes, including starch metabolism, defense, and cell-wall remodeling. Glycoside hydrolase genes have been previously cataloged for Oryza sativa (rice), the model dicotyledonous plant Arabidopsis thaliana, and the fast-growing tree Populus trichocarpa (poplar). To improve our understanding of glycoside hydrolases in plants generally and in grasses specifically, we annotated the glycoside hydrolase genes in the grasses Brachypodium distachyon (an emerging monocotyledonous model) and Sorghum bicolor (sorghum). We then compared the glycoside hydrolases across species, both at the whole-genome level and at the level of individual glycoside hydrolase families. Results We identified 356 glycoside hydrolase genes in Brachypodium and 404 in sorghum. The corresponding proteins fell into the same 34 families that are represented in rice, Arabidopsis, and poplar, helping to define a glycoside hydrolase family profile which may be common to flowering plants. Examination of individual glycoside hydrolase familes (GH5, GH13, GH18, GH19, GH28, and GH51) revealed both similarities and distinctions between monocots and dicots, as well as between species. Shared evolutionary histories appear to be modified by lineage-specific expansions or deletions. Within families, the Brachypodium and sorghum proteins generally cluster with those from other monocots. Conclusions This work provides the foundation for further comparative and functional analyses of plant glycoside hydrolases. Defining the Brachypodium glycoside hydrolases sets the stage for Brachypodium to be a monocot model for investigations of these enzymes and their diverse roles in planta. Insights gained from Brachypodium will inform translational research studies, with applications for the improvement of cereal crops and bioenergy grasses.

Tyler, Ludmila [USDA-ARS Western Regional Research Center; Bragg, Jennifer [USDA-ARS Western Regional Research Center; Wu, Jiajie [USDA-ARS Western Regional Research Center; Yang, Xiaohan [ORNL; Tuskan, Gerald A [ORNL; Vogel, John [USDA-ARS Western Regional Research Center

2010-01-01

367

Changes in histamine secretion from mast cells caused by digitalis glycosides  

Microsoft Academic Search

Cardiotonic glycosides modify histamine secretion from rat mast cells in the following way. (1) Preincubation (30 min) of mast cells with liposoluble glycosides (10?4 mol\\/l) increases the spontaneous histamine secretion by about 5%. (2) Preincubation of mast cells with 10?4 mol\\/l liposoluble glycosides (digitoxine, digoxine, digitoxigenine) decreases histamine release induced by compound 48\\/80 in the presence of calcium, whereas the

F. Erjavec; I. Ferjan

1990-01-01

368

MATE2 Mediates Vacuolar Sequestration of Flavonoid Glycosides and Glycoside Malonates in Medicago truncatula[C][W][OA  

PubMed Central

The majority of flavonoids, such as anthocyanins, proanthocyanidins, and isoflavones, are stored in the central vacuole, but the molecular basis of flavonoid transport is still poorly understood. Here, we report the functional characterization of a multidrug and toxin extrusion transporter (MATE2), from Medicago truncatula. MATE 2 is expressed primarily in leaves and flowers. Despite its high similarity to the epicatechin 3?-O-glucoside transporter MATE1, MATE2 cannot efficiently transport proanthocyanidin precursors. In contrast, MATE2 shows higher transport capacity for anthocyanins and lower efficiency for other flavonoid glycosides. Three malonyltransferases that are coexpressed with MATE2 were identified. The malonylated flavonoid glucosides generated by these malonyltransferases are more efficiently taken up into MATE2-containing membrane vesicles than are the parent glycosides. Malonylation increases both the affinity and transport efficiency of flavonoid glucosides for uptake by MATE2. Genetic loss of MATE2 function leads to the disappearance of leaf anthocyanin pigmentation and pale flower color as a result of drastic decreases in the levels of various flavonoids. However, some flavonoid glycoside malonates accumulate to higher levels in MATE2 knockouts than in wild-type controls. Deletion of MATE2 increases seed proanthocyanidin biosynthesis, presumably via redirection of metabolic flux from anthocyanin storage.

Zhao, Jian; Huhman, David; Shadle, Gail; He, Xian-Zhi; Sumner, Lloyd W.; Tang, Yuhong; Dixon, Richard A.

2011-01-01

369

Effects of purified persimmon tannin and tannic acid on survival and reproduction of bean bug, Riptortus clavatus.  

PubMed

We evaluated the effects of tannic acid and purified perrsimmon tannin on survival and reproduction of bean bugs, Riptortus clavatus.Feeding behavior of R. clavatus was also examined on sweet (cv. Fuyu) and astringent (cv. Chongdosi) persimmon fruits. Soluble tannin in sweet persimmon fruits decreased from 3% in early June to 0.5% in late September, but it increased from 2 to 8% during the same period in astringent persimmon fruits. More bugs visited sweet than astringent persimmon. Numbers of piercing/sucking spots were higher on sweet than on astringent persimmon. When fed 1 and 3% solutions of persimmon tannin, adult bugs ingested only 64.1 and 9.5% of the amount of water ingested by those offered the control (distilled water). Amounts of persimmon tannin ingested by the adult bugs were 6.5 and 2.8 times higher at 1 and 3% tannin solutions compared to a 0.1% solution. Persimmon tannin exerted negative effects on survival and reproduction of R. clavatus at higher concentrations (1 and 3% solutions). Feeding of R. clavatus adults decreased with increasing tannin concentrations. When results from both sexes were pooled, 50% mortality was achieved at 11 and 4 days after treatment with the 1 and 3% tannin solutions, respectively. Reproduction decreased with 1% tannin, and no eggs were produced with 3% tannin solution. Tannic acid was similar in its effects on R. clavatus. All nymphs died 14, 12, and 7 days after feeding on 0.1, 1, and 3% tannic acid, respectively. Adults were less sensitive than nymphs, and their survival was not affected by 0.1% tannic acid. However. 1 and 3% tannic acid solutions were fatal. Survivorship decreased to 50% at 11 and 6 days after supplying tannin solutions of 1 and 3% concentrations. Higher concentrations (1 and 3%) resulted in reduced reproduction, as was seen with persimmon tannin. Our data may explain why R. clavatus does not invade sweet persimmon orchards until late July, when concentrations of soluble tannin are low enough to allow them to feed. PMID:15672670

Park, Chung Gyoo; Lee, Kyu Chul; Lee, Dong Woon; Choo, Ho Yul; Albert, P J

2004-11-01

370

Glycosides from marine sponges (Porifera, Demospongiae): structures, taxonomical distribution, biological activities and biological roles.  

PubMed

Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

Kalinin, Vladimir I; Ivanchina, Natalia V; Krasokhin, Vladimir B; Makarieva, Tatyana N; Stonik, Valentin A

2012-08-01

371

Glycosides from Marine Sponges (Porifera, Demospongiae): Structures, Taxonomical Distribution, Biological Activities and Biological Roles  

PubMed Central

Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed.

Kalinin, Vladimir I.; Ivanchina, Natalia V.; Krasokhin, Vladimir B.; Makarieva, Tatyana N.; Stonik, Valentin A.

2012-01-01

372

Effects of tannins on the decomposition of Chinese tallow leaves by terrestrial and aquatic invertebrates  

Microsoft Academic Search

The hypothesis of this study was that tannins from Chinese tallow leaves have a negative effect upon terrestrial and aquatic reducer organisms and thereby may affect the overall rate of tallow litter decomposition. Species diversity and population size of aquatic reducers was lower in forest than adjacent grassland ponds; litter bags showed no difference in weight loss between bags which

Guy N. Cameron; Thomas W. LaPoint

1978-01-01

373

Molecular diversity in phenolic and polyphenolic precursors of tannin-inspired nanocoatings.  

PubMed

The strong interfacial properties of selected plant polyphenols were recently exploited in forming functionally versatile nanocoatings via dip-coating. Here, we screened a library of ?20 natural and synthetic phenols and polyphenols, identifying eight catechol-, gallol- and resorcinol-rich precursors capable of forming coatings. Several newly identified compounds expand the molecular diversity of tannin-inspired coatings. PMID:24871486

Barrett, Devin G; Sileika, Tadas S; Messersmith, Phillip B

2014-06-12

374

[HPLC-fingerprint-based quality evaluation on a Tibetan medicine Phyllanthus emblica and its tannin parts].  

PubMed

This study is to establish the fingerprint for Phyllanthus emblica and their tannin parts from different habitats by HPLC for its quality control. The determination was carried out on a Diamonsil C18 (4.6 mm x 250 mm, 5 microm) column, with methanol-0.2% glacial acetic acid as mobile phase with gradient elution at a flow rate of 1 mL x min(-1). The temperature was maintained at 30 degrees C and the detected wavelength is 260 nm, Thirteen chromatographic peaks were extracted as the common peaks of the fingerprint of P. emblica, and eleven as the common peaks of P. emblica tannin parts, and five peaks were identified by comparing with referent samples. The fingerprints of 8 samples were compared and classified by similarity evaluation, cluster analysis and principal component analysis (PCA). The similarity degrees of eight P. emblica were between 0.763 and 0.993, while tannin parts were between 0.903 and 0.991. All the samples of P. emblica and their tannin parts were classified into 3 categories. The method was so highly reproducible, simple and reliable that it could provide basis for quality control and evaluation of P. emblica from different habitats. PMID:25011249

Sun, Xue-Fei; Zhang, Hong-Yan; Xia, Qing; Zhao, Hai-Juan; Wu, Ling-Fang; Zhang, Lan-Zhen; Shi, Ren-Bing

2014-04-01

375

Effect of drying method and assay methodology on detergent fiber analysis in plants containing condensed tannins  

Microsoft Academic Search

Laboratory evaluation of fiber concentration and nutritive value of plants containing condensed tannins (CT) can be complicated by the formation of strong complexes between CT and other molecules as affected by sample preparation and assay methodology. This study looked at fiber and acid detergent insoluble nitrogen (ADIN) concentrations of 10 herbaceous and brushy species with and without naturally occurring CT.

Suzika Pagán; Richard M. Wolfe; Thomas H. Terrill; James P. Muir

2009-01-01

376

In vitro quality assessment of two tropical shrub legumes in relation to their extractable tannins contents.  

PubMed

The in vitro dry matter digestibility (IVDMD) of the two leguminous tree fodders Gliricidia sepium and Calliandra calothyrsus which differ in their tannin content was examined by the rumen simulation technique. Extractable condensed tannin (CT) concentrations ranged from 0.57% in G. sepium to 5.05% in C. calothyrsus using the butanol-HCl extraction. On the basis of their respective CT contents, G. sepium was classified as containing traces of CT, whereas C. calothyrsus had medium amounts of CT. Polyethylene glycol (PEG) was added at different concentrations (0, 1.5, 5 and 10 g/100 g plant material substrate) to assess the effect of tannins on IVDMD. The IVDMD was higher for G. sepium (range: 60-65%) than for C. calothyrsus (39.5-53.5%). In vitro gas production and IVDMD increased with increased PEG concentrations especially for C. calothyrsus. A non-significant response to increasing PEG concentrations for IVDMD of G. sepium confirms PEG binding with the tannins. On the basis of these results, it is assumed that G. sepium has a higher nutritive value than C. calothyrsus. Good relationship between PEG binding and the improvement of IVDMD confirms the usefulness of this technique for improving the nutritive value of tanniniferous tropical browses. PMID:14511135

Seresinhe, T; Iben, C

2003-04-01

377

Field studies of the relationship between herbivore damage and tannin concentration in bracken ( Pteridium aquilinum Kuhn)  

Microsoft Academic Search

The acceptance of secondary plant metabolites as herbivore deterrents rests primarily on their deleterious effects on herbivores. Efforts to demonstrate differential fitness in natural plant populations with varying concentrations of tannin have failed, since coevolved plant predators may physiologically or behaviorally circumvent the defense, which results in apparently equal amounts of damage to defended and undefended individuals. In this study,

Alice S. Tempel

1981-01-01

378

Woodfordin D and oenothein A, trimeric hydrolyzable tannins of macro-ring structure with antitumor activity.  

PubMed

Two new antitumor trimeric hydrolyzable tannins, woodfordin D (5) and oenothein A (13), were isolated from the dried flowers of Woodfordia fruticosa, and their macrocyclic structures, which have a novel constituent unit (woodfordinoyl group) connecting the monomers, have been elucidated on the basis of spectral and chemical evidence. Oenothein A (13) was also isolated from the leaves of Oenothera biennis. PMID:1913994

Yoshida, T; Chou, T; Matsuda, M; Yasuhara, T; Yazaki, K; Hatano, T; Nitta, A; Okuda, T

1991-05-01

379

[Action of isolanide in acute cardiac insufficiency in rats].  

PubMed

Acute teste staged on rats showed low doses of the cardiac glycoside isolanide to bring down the level of total lipids, cholesterol and beta-lipoproteins, without causing any changes in the content of NAD, adenyl nucleotides, non-esterified fatty acids (NEFA) and of phospholipids in themyocardium. Large doses of the drug uniformly reduce the content of all the co-enzymes fractions, the amount of ARP, ADP, cholesterol, beta-lipoproteins and the raise the level of total lipids, phospholipids and NEFA. In cases of acute cardiac insufficiency the drug produces a normalizing action on the co-enzymes and adenyl nucleotides content and reduces that of beta-lipoproteins and cholesterol. It appears that a definite part in the mechanism of the isolanide action plays its influence on the level of nucotinamide co-enzymes, adenyl nucleotides and lipids. PMID:923775

Gorchakova, N A; Poliakova, I F; Rubchinskaia, K I; Samilova, R D

1977-01-01

380

CARDIAC MUSCLE  

PubMed Central

With light and electron microscopy a comparison has been made of the morphology of ventricular (V) and Purkinje (P) fibers of the hearts of guinea pig, rabbit, cat, dog, goat, and sheep. The criteria, previously established for the rabbit heart, that V fibers are distinguished from P fibers by the respective presence and absence of transverse tubules is shown to be true for all animals studied. No evidence was found of a permanent connection between the sarcoplasmic reticulum and the extracellular space. The sarcoplasmic reticulum (SR) of V fibers formed couplings with the sarcolemma of a transverse tubule (interior coupling) and with the peripheral sarcolemma (peripheral coupling), whereas in P fibers the SR formed only peripheral couplings. The forms of the couplings were identical. The significance, with respect to excitation-contraction coupling, of the difference in the form of the couplings in cardiac versus skeletal muscle is discussed together with the electrophysiological implications of the differing geometries of bundles of P fibers from different animals.

Sommer, Joachim R.; Johnson, Edward A.

1968-01-01

381

NMR and molecular modeling of wine tannins binding to saliva proteins: revisiting astringency from molecular and colloidal prospects.  

PubMed

In organoleptic science, the association of tannins to saliva proteins leads to the poorly understood phenomenon of astringency. To decipher this interaction at molecular and colloidal levels, the binding of 4 procyanidin dimers (B1-4) and 1 trimer (C2) to a human saliva proline-rich peptide, IB7(14), was studied. Interactions have been characterized by measuring dissociation constants, sizes of complexes, number, and nature of binding sites using NMR (chemical shift variations, diffusion-ordered spectroscopy, and saturation transfer diffusion). The binding sites were identified using molecular mechanics, and the hydrophilic/hydrophobic nature of the interactions was resolved by calculating the molecular lipophilicity potential within the complexes. The following comprehensive scheme can be proposed: 1) below the tannin critical micelle concentration (CMC), interaction is specific, and the procyanidin anchorage always occurs on the same three IB7(14) sites. The tannin 3-dimensional structure plays a key role in the binding force and in the tannin's ability to act as a bidentate ligand: tannins adopting an extended conformation exhibit higher affinity toward protein and initiate the formation of a network. 2) Above the CMC, after the first specific hydrophilic interaction has taken place, a random hydrophobic stacking occurs between tannins and proteins. The whole process is discussed in the general frame of wine tannins eliciting astringency. PMID:20605948

Cala, Olivier; Pinaud, Noël; Simon, Cécile; Fouquet, Eric; Laguerre, Michel; Dufourc, Erick J; Pianet, Isabelle

2010-11-01

382

Effects of condensed tannin from Acacia mearnsii on sheep infected naturally with gastrointestinal helminthes.  

PubMed

The effect of tannins on endoparasite control in hair sheep was investigated using 20 entire lambs of the Santa Inês breed. At the beginning of the experiment these animals were 6-months old and weighed 22.5kg+/-4.7. The treatments used were (10 animals each): GT (animals receiving 18g of Acácia negra containing 18% of condensed tannin/animal/week) and GC (animals not receiving tannin). The experiment lasted 84 days, with animals kept on an Andropogon gayanus pasture. Faeces were collected weekly, with weighing and blood collection carried out fortnightly. At slaughter, the adult worms were harvested for identification and counting. Although the GT animals weighed more than the GC lambs at slaughter, these differences were not significant (P>0.05). In general, the values for haemoglobin, hematocrit, total protein, urea, phosphorus and calcium in the serum were within normal levels and no significant differences between groups were observed. For faecal egg count (FEC), lower values were observed throughout the experiment in the group receiving tannin, but these differences were only significant in the eighth week. There was a lower output of eggs by regression for GT compared with GC (P<0.05). The species identified, in decreasing order of worm count, were: Trichostrongylus colubriformis, Haemonchus contortus, Oesophagostomum columbianum, Cooperia sp., Strongyloides papillosus, Trichuris globulosa and Moniezia expansa. The total worm count and number of each species of worm were lower for GT compared with GC for T. colubriformis and Cooperia sp. (P<0.05). Condensed tannin (CT) from A. negra had an antiparasitic effect, thereby representing an alternative for worm control in sheep. PMID:17067741

Cenci, F B; Louvandini, H; McManus, C M; Dell'Porto, A; Costa, D M; Araújo, S C; Minho, A P; Abdalla, A L

2007-03-15

383

Adams-Harbertson protein precipitation-based wine tannin method found invalid.  

PubMed

The poor precision of the Adams-Harbertson wine tannin assay which was proposed for commercial winemaking, thereby creating the real possibility of quality control problems, is documented. The method is a version of the Hagerman and Butler protein precipitation-based tannin method. An extensive invalidation of the assay results with luxury wine data shows that the assay cannot distinguish bottled wine with reasonable accuracy. Five laboratories used Adams-Harbertson to assay 9 replicates each, of 3 bottled wines (n = 135) found in California supermarkets, with tannin concentrations of nominally 500 and 1000 ppm by high-performance liquid chromatography (HPLC). Reliability exceeded the +/-5% industry requirement by nominally 5 times (z-score based on 5% distribution). Coefficient of variation was +/-27%, making the standard deviation range 54% for Pinot Noir, 34% for Merlot, and 44% for Cabernet Sauvignon. Validity exceeded the 100% requirement. Intralaboratory validity recovery was 55-63%. Interwinery validity was 71-178% of the mean for Pinot Noir, 81-144% for Merlot, and 83-164% for Cabernet Sauvignon. Range as a function of the mean was 89% for Pinot Noir, 55% for Merlot, and 67% for Cabernet Sauvignon. Expect intermethod validity to be nominally 50%, i.e., percent recovery to HPLC. These statistically significant errors were predicted by the literature. First-order error is related to the tannin-protein equilibrium constant (Ka), as suggested by the original author, Hagerman, and the protein equivalence point error as suggested by Silber. This does not obviate second-order errors for tannin-protein analytical chemistry. Winemakers using the measurements risk making wines that are relatively more tannic than the measurements report. PMID:18980123

Brooks, Larry; McCloskey, Leo; McKesson, Doug; Sylvan, Marshall

2008-01-01

384

Effects of sorghum (Sorghum bicolor (L.) Moench) tannins on ?-amylase activity and in vitro digestibility of starch in raw and processed flours.  

PubMed

The purpose of this study was to investigate the effects of tannins on starch digestion in tannin-containing sorghum extracts and wholegrain flours from 12 sorghum varieties. Extracts reduced amylase activity in a tannin concentration-dependent manner when the extract was mixed with the enzyme before substrate (amylopectin) addition, with higher molecular weight tannins showing greater reduction. Conversely, when the extract and substrate were combined before enzyme addition an enhancement in amylase activity was experienced. In uncooked, cooked, and cooked and stored wholegrain sorghum flours, rapidly digestible, slowly digestible, and resistant starches were not correlated with tannin content or molecular weight distribution. Resistant starch increased from 6.5% to 22-26% when tannins were added to starch up to 50% (starch weight). Tannin extracts both reduced and enhanced amylase activity depending on conditions, and, while these trends were clear in extracts, the effects on starch digestion in wholegrain flours was more complex. PMID:23581620

Mkandawire, Nyambe L; Kaufman, Rhett C; Bean, Scott R; Weller, Curtis L; Jackson, David S; Rose, Devin J

2013-05-01

385

The effects of high-tannin leaf litter from transgenic poplars on microbial communities in microcosm soils  

PubMed Central

The impacts of leaf litter from genetically modified hybrid poplar accumulating high levels of condensed tannins (proanthocyanidins) were examined in soil microcosms consisting of moss growing on sieved soil. Moss preferentially proliferated in microcosms with lower tannin content; DGGE (denaturing gradient gel electrophoresis) detected increased fungal diversity in microcosms with low-tannin litter. The proportion of cloned rDNA sequences from Actinobacteria decreased with litter addition while Bacteroidetes, Chloroflexi, Cyanobacteria, and ?-Proteobacteria significantly increased. ?-Proteobacteria were proportionally more numerous at high-tannin levels. Tannins had no significant impact on overall diversity of bacterial communities analyzed with various estimators. There was an increased proportion of N-fixing bacteria corresponding to the addition of litter with low-tannin levels. The addition of litter increased the proportion of Ascomycota/Basidiomycota. Dothideomycetes, Pucciniomycetes, and Tremellomycetes also increased and Agaricomycetes decreased. Agaricomycetes and Sordariomycetes were significantly more abundant in controls, whereas Pucciniomycetes increased in soil with litter from transformed trees (P = 0.051). Richness estimators and diversity indices revealed no significant difference in the composition of fungal communities; PCoA (principal coordinate analyses) partitioned the fungal communities into three groups: (i) those with higher amounts of added tannin from both transformed and untransformed treatments, (ii) those corresponding to soils without litter, and (iii) those corresponding to microcosms with litter added from trees transformed only with a ?-glucuronidase control vector. While the litter from transformed poplars had significant effects on soil microbe communities, the observed impacts reflected known impacts on soil processes associated with tannins, and were similar to changes that would be expected from natural variation in tannin levels.

Winder, Richard S.; Lamarche, Josyanne; Constabel, C. Peter; Hamelin, Richard C.

2013-01-01

386

Bacterial and protozoal communities and fatty acid profile in the rumen of sheep fed a diet containing added tannins.  

PubMed

This study evaluated the effects of tannins on ruminal biohydrogenation (BH) due to shifts in the ruminal microbial environment in sheep. Thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). At 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis and sampled to quantify populations of Butyrivibrio fibrisolvens, which converts C(18:2) c9-c12 (linoleic acid [LA]) to C(18:2) c9-t11 (rumenic acid [RA]) and then RA to C(18:1) t11 (vaccenic acid [VA]); we also sampled for Butyrivibrio proteoclasticus, which converts VA to C(18:0) (stearic acid [SA]). Tannins increased (P < 0.005) VA in the rumen compared to the tannin-free diet. The concentration of SA was not affected by tannins. The SA/VA ratio was lower (P < 0.005) for the tannin-fed lambs than for the controls, suggesting that the last step of the BH process was inhibited by tannins. The B. proteoclasticus population was lower (-30.6%; P < 0.1), and B. fibrisolvens and protozoan populations were higher (+107% and +56.1%, respectively; P < 0.05) in the rumen of lambs fed the tannin-supplemented diet than in controls. These results suggest that quebracho tannins altered BH by changing ruminal microbial populations. PMID:20173064

Vasta, Valentina; Yáñez-Ruiz, David R; Mele, Marcello; Serra, Andrea; Luciano, Giuseppe; Lanza, Massimiliano; Biondi, Luisa; Priolo, Alessandro

2010-04-01

387

Bacterial and Protozoal Communities and Fatty Acid Profile in the Rumen of Sheep Fed a Diet Containing Added Tannins ?  

PubMed Central

This study evaluated the effects of tannins on ruminal biohydrogenation (BH) due to shifts in the ruminal microbial environment in sheep. Thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). At 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis and sampled to quantify populations of Butyrivibrio fibrisolvens, which converts C18:2 c9-c12 (linoleic acid [LA]) to C18:2 c9-t11 (rumenic acid [RA]) and then RA to C18:1 t11 (vaccenic acid [VA]); we also sampled for Butyrivibrio proteoclasticus, which converts VA to C18:0 (stearic acid [SA]). Tannins increased (P < 0.005) VA in the rumen compared to the tannin-free diet. The concentration of SA was not affected by tannins. The SA/VA ratio was lower (P < 0.005) for the tannin-fed lambs than for the controls, suggesting that the last step of the BH process was inhibited by tannins. The B. proteoclasticus population was lower (?30.6%; P < 0.1), and B. fibrisolvens and protozoan populations were higher (+107% and +56.1%, respectively; P < 0.05) in the rumen of lambs fed the tannin-supplemented diet than in controls. These results suggest that quebracho tannins altered BH by changing ruminal microbial populations.

Vasta, Valentina; Yanez-Ruiz, David R.; Mele, Marcello; Serra, Andrea; Luciano, Giuseppe; Lanza, Massimiliano; Biondi, Luisa; Priolo, Alessandro

2010-01-01

388

Effect of condensed tannins on bovine rumen protist diversity based on 18S rRNA gene sequences.  

PubMed

Molecular diversity of protists from bovine rumen fluid incubated with condensed tannins of Leucaena leucocephala hybrid-Rendang at 20 mg/500 mg dry matter (treatment) or without condensed tannins (control) was investigated using 18S rRNA gene library. Clones from the control library were distributed within nine genera, but clones from the condensed tannin treatment clone library were related to only six genera. Diversity estimators such as abundance-based coverage estimation and Chao1 showed significant differences between the two libraries, although no differences were found based on Shannon-Weaver index and Libshuff. PMID:23205499

Tan, Hui Yin; Sieo, Chin Chin; Abdullah, Norhani; Liang, Juan Boo; Huang, Xiao Dan; Ho, Yin Wan

2013-01-01

389

Steroidal glycosides from the underground parts of Helleborus caucasicus.  

PubMed

Four polyhydroxylated and polyunsaturated furostanol glycosides (1-4), named caucasicosides A (1), B (2), C (3) and D (4), were isolated from the MeOH extract of the underground parts of Helleborus caucasicus, along with four spirostanol derivatives, a furostanol glycoside, a furospirostanol glycoside, 20-hydroxyecdysone and the bufadienolides hellebrigenin and deglucohellebrin. The structures of 1-4 were elucidated as furosta-5,20(22),25(27)-triene-1beta,3beta,11alpha,26-tetrol 26-O-beta-D-glucopyranoside (1), 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1beta,3beta,11alpha,26-tetrol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (2), 26-O-beta-d-glucopyranosyl-22alpha-methoxyfurosta-5,25(27)-diene-1beta,3beta,11alpha,26-tetrol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (3), 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1beta,3beta,26-triol 3-O-beta-D-xylopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-4-O-sulfo-alpha-L-arabinopyranoside (4). Structure elucidation was accomplished through the extensive use of 1D- and 2D NMR experiments including 1H-1H (COSY, 1D-TOCSY) and 1H-13C (HSQC, HMBC) spectroscopy along with ESI-MS and HR-ESI-MS. The aglycones of 1-4 have never been reported before. PMID:18226823

Bassarello, Carla; Muzashvili, Tamara; Skhirtladze, Alexandre; Kemertelidze, Ether; Pizza, Cosimo; Piacente, Sonia

2008-03-01

390

A new flavonol glycoside from the Abelmoschus esculentus Linn.  

PubMed Central

Background: Abelmoschus esculentus L. belonging to the family Malvaceae is a kind of one year herbage plant, which is one of the most important vegetables widely grown in Nigeria for its tender fruits and young leaves. It's easy to be cultivated and grows well in both tropical and temperate zones, that is, it is widely planted from Africa to Asia, South European to America. A new flavonol glycoside characterized as 5,7,3?,4?-tetrahydroxy-4??-O-methyl flavonol -3-O-?-D- glucopyranoside (1) has been isolated from the fruit of A. esculentus together with one known compound 5,7,3?,4?-tetrahydroxy flavonol -3-O-[?-D-glucopyranosyl-(1?6)]-?-D-glucopyranoside (2). The structure of the new compound was elucidated on the basis of its spectral data, including 2-D NMR and mass (MS) spectra. The antioxidant activities of the isolated compounds 1 and 2 were evaluated by 2 assays, the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). The present work deals with the isolation, identification and antioxidant activity of the two compounds. Materials and Methods: The compounds were isolated by Diaion HP-20, Sephedex LH-20 column chromatography methods, their structures were identified by physicochemical properties and spectroscopic analysis. The antioxidant activities of the isolated compounds 1 and 2 were evaluated by two assays, e.g., DPPH and FRAP. Results: Two flavonol glycosides have been isolated from the fruit of Abelmoschus esculentus L. for the first time, and the compound 1 was a new compound, the compound 2 was isolated from the plant for the first time. Conclusion: The results show that the two flavonol glycosides have strong ability for scavenging DPPH and FRAP free radical by the experiment of antioxidant activities, so A. esculentus may be a natural antioxidants resource.

Liao, Haibing; Liu, Huixin; Yuan, Ke

2012-01-01

391

Inhibition of amyloid ? aggregation by acteoside, a phenylethanoid glycoside.  

PubMed

We examined the effects of acteoside (1a), which was isolated from Orobanche minor, and its derivatives on the aggregation of a 42-mer amyloid ? protein (A?42) in our search for anti-amyloidogenic compounds for Alzheimer's disease (AD) therapy. Acteoside (1a) strongly inhibited the aggregation of A?42 in a dose-dependent manner. The structure-activity relationship for acteoside (1a) and related compounds suggests the catechol moiety of phenylethanoid glycosides to be essential for this inhibitory activity. PMID:23748773

Kurisu, Manami; Miyamae, Yusaku; Murakami, Kazuma; Han, Junkyu; Isoda, Hiroko; Irie, Kazuhiro; Shigemori, Hideyuki

2013-01-01

392

Four New Flavonol Glycosides from the Leaves of Brugmansia suaveolens.  

PubMed

Four new flavonol glycosides were isolated from the leaves of Brugmansia suaveolens: kaempferol 3-O-?-D-glucopyranosyl-(1'''?2'')-O-?-L-arabinopyranoside (1), kaempferol 3-O-?-D-glucopyranosyl-(1'''?2'')-O-?-L-arabinopyranoside-7-O-?-D-gluco-pyranoside (2), kaempferol 3-O-?-D-[6'''-O-(E-caffeoyl)]-glucopyranosyl-(1'''?2'')-O-?-l-arabinopyranoside-7-O-?-D-glucopyranoside (3), and kaempferol 3-O-?-D-[2'''-O-(E-caffeoyl)]-glucopyranosyl-(1'''?2'')-O-?-l-arabinopyranoside-7-O-?-D-glucopyranoside (4). The structure elucidation was performed by MS, 1D and 2D NMR analyses. PMID:24858103

Geller, Fabiana; Murillo, Renato; Steinhauser, Lisa; Heinzmann, Berta; Albert, Klaus; Merfort, Irmgard; Laufer, Stefan

2014-01-01

393

A new phenolic amide glycoside from Cimicifuga dahurica.  

PubMed

A new phenolic amide glycoside, cimicifugamide A (1) along with four known compounds, trans-feruloyl tyramine 4-O-beta-D-glucopyranoside (2), (+)-isolariciresinol 3-O-beta-D-glucopyranoside (3), cimidahurine (4), and 24-epi-7, 8-didehydrocimigenol-3-O-beta-D-xylopyranoside (5) were isolated from the rhizomes of Cimicifuga dahurica. Compound 3 was identified as a lignan and has been obtained from Cimicifuga genus for the first time. The structure of compound 1 was elucidated by IR, UV, HR-MS and NMR spectroscopic methods. PMID:24187836

Zhang, Fan; Han, Li-Feng; Pan, Gui-Xiang; Peng, Shuang; Andre, Ndagijimana

2013-08-01

394

A new spirostanol glycoside from fruits of Solanum indicum L.  

PubMed

A new characteristic steroidal glycoside of the 23S,26R-hydroxylated spirostanol-type named indioside F was isolated from the fruit of Solanum indicum, along with indioside A and protodioscin. On the basis of spectroscopic analysis, the structure of indioside F was found to be 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranosyl (beta-chacotriosyl) (22R,23S,25R,26R)-spirost-5-ene-3beta,23,26-triol. PMID:19571425

El-Aasr, Mona; Miyashita, Hiroyuki; Ikeda, Tsuyoshi; Lee, Jong-Hyun; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Murakami, Kotaro

2009-07-01

395

A new hexenol glycoside from leaves of Smallanthus sonchifolius  

Microsoft Academic Search

A new hexenol glycoside with two known compounds was isolated from the leaves of Smallanthus sonchifolius. The structure of the new compound was elucidated as Z-hex-3-en-1-ol O-alpha-L-arabinopyransyl (1??-2?)-beta-D-glucopyranoside (1) on the basis of spectroscopic analysis and chemical evidence. The two known compounds were identified as ent-15?-hydroxy-kaur-16-en-19-oic acid (2) and ent-18-hydroxy-kaur-16-en-19-oic acid (3) by comparison of their spectral data with the

Xiang Zheng; Gai Kuo; Dou De-Qiang; Chen Gui-Rong; Kang Ting-Guo; Shi Yu-Yuan; Li Xing-Tai; Dong Feng

2010-01-01

396

A new cucurbitacin glycoside from Kageneckia oblonga (Rosaceae).  

PubMed

A novel cucurbitacin glycoside has been isolated from aerial parts of Kageneckia oblonga R. et P. and shown to be 3beta-(beta-D-glucosyloxy)-16alpha,23alpha-epoxycuc urbita-5,24-dien-11-one. The structure was established by usual spectroscopic and two-dimensional (2D) NMR techniques. This compound has found to be nontoxic when tested in-vivo cell culture assays. In previous investigations we reported 23,24-dihydrocucurbitacin F and prunasine. This was the first report on cucurbitacins from the genus Kageneckia (Rosaceae). PMID:10817201

Muñoz, O; Delporte, C; Backhouse, N; Erazo, S; Negrete, R; Maldonado, S; López-Pérez, J L; San Feliciano, A

2000-01-01

397

Two new phenolic glycosides from the rhizome of Gastrodia elata  

Microsoft Academic Search

Two new phenolic glycosides, named parishins F–G (1–2), together with known parishin E, were isolated from the rhizome of Gastrodia elata. The new structures were established as 1,3-di-[4-O-(?-d-glucopyranosyl) benzyl]-2-{4-O-[?-d-glucopyranosyl-(1 ? 6)-?-d-glucopyranosyl] benzyl} citrate (1) and 2-[4-O-(?-d-glucopyranosyl)benzyl] citrate (2), by means of MS, 1D, and 2D NMR spectral analyses, as well as chemical methods.

Li Wang; Hong-Bin Xiao; Li Yang; Zheng-Tao Wang

2012-01-01

398

Two new phenolic glycosides from the rhizome of Gastrodia elata.  

PubMed

Two new phenolic glycosides, named parishins F-G (1-2), together with known parishin E, were isolated from the rhizome of Gastrodia elata. The new structures were established as 1,3-di-[4-O-(?-D-glucopyranosyl) benzyl]-2-{4-O-[?-D-glucopyranosyl-(1 ? 6)-?-D-glucopyranosyl] benzyl} citrate (1) and 2-[4-O-(?-D-glucopyranosyl)benzyl] citrate (2), by means of MS, 1D, and 2D NMR spectral analyses, as well as chemical methods. PMID:22428666

Wang, Li; Xiao, Hong-Bin; Yang, Li; Wang, Zheng-Tao

2012-01-01

399

Pentasaccharide resin glycosides from Ipomoea cairica and their cytotoxic activities.  

PubMed

Six partially acylated pentasaccharide resin glycosides, cairicosides A-F, were isolated from the aerial parts of Ipomoea cairica. These compounds were characterized as a group of macrolactones of simonic acid A, partially acylated with different organic acids. The lactonization site of 11S-hydroxyhexadecanoic acid (jalapinolic acid) was bound to the second saccharide moiety at C-3 in cairicosides A-E, while at C-2 in cairicoside F. Structures were established by spectroscopic and chemical methods. Compounds cairicosides A-E exhibited moderate cytotoxicity against a small panel of human tumor cell lines with IC50 values in the range of 4.28-14.31?M. PMID:23954073

Yu, Bangwei; Luo, Jianguang; Wang, Junsong; Zhang, Dongming; Yu, Shishan; Kong, Lingyi

2013-11-01

400

Antioxidative activity of the crude extract of lignan glycosides from unroasted Burma black sesame meal  

Microsoft Academic Search

Sesame seed contains lignans and lignan glycosides. The antioxidative activity of the crude extract of lignan glycosides obtained from unroasted defatted black sesame seeds was investigated in this study. The components responsible for the antioxidative activity were also studied. The unroasted black sesame seeds, after defatted with n-hexane, were extracted with 80% methanolic solution to prepare for the crude extract

Yung-Shin Shyu; Lucy Sun Hwang

2002-01-01

401

Two new nor-triterpene glycosides from peruvian "Uña de Gato" (Uncaria tomentosa).  

PubMed

Two new 27-nor-triterpene glycosides, tomentosides A (1) and B (2), were isolated from Peruvian "Uña de Gato" (cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis and chemical interconversions. This is the first report of naturally occurring pyroquinovic acid glycosides. PMID:12608878

Kitajima, Mariko; Hashimoto, Ken-Ichiro; Yokoya, Masashi; Takayama, Hiromitsu; Sandoval, Manuel; Aimi, Norio

2003-02-01

402

Determining levels of steviol glycosides in the leaves of Stevia rebaudiana by near infrared reflectance spectroscopy  

Microsoft Academic Search

The sweet diterpene glycosides extracted from the leaves of Stevia rebaudiana (Bert) Bertoni are of increasing interest in recent years as possible sugar substitutes. Our objectives were to investigate the application of near infrared reflectance spectroscopy (NIRS) in analysis of steviol glycosides (SGs) concentration (w\\/w) dry basis in S. rebaudiana leaves, using high-pressure liquid chromatography (HPLC) as the reference method.

L. K. Hearn; P. P. Subedi

2009-01-01

403

Cardiac Risk Assessment  

MedlinePLUS

... website will be limited. Search Help? Cardiac Risk Assessment Share this page: Was this page helpful? Formal ... Questions | Related Pages What is a cardiac risk assessment? This is a group of tests and health ...

404

Cardiac sodium channelopathies  

Microsoft Academic Search

Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward\\u000a depolarizing current (INa) during phase 0 of the cardiac action potential. The importance of INa for normal cardiac electrical activity is reflected by the high incidence of arrhythmias in cardiac sodium channelopathies,\\u000a i.e., arrhythmogenic diseases in patients with mutations in SCN5A,

Ahmad S. Amin; Alaleh Asghari-Roodsari; Hanno L. Tan

2010-01-01

405

Understanding cardiac output  

PubMed Central

Cardiac output is the amount of blood the heart pumps in 1 minute, and it is dependent on the heart rate, contractility, preload, and afterload. Understanding of the applicability and practical relevance of each of these four components is important when interpreting cardiac output values. In the present article, we use a simple analogy comparing cardiac output with the speed of a bicycle to help appreciate better the effects of various disease processes and interventions on cardiac output and its four components.

Vincent, Jean-Louis

2008-01-01

406

Target-specific imaging of transmembrane receptors using quinonyl glycosides functionalized quantum dots.  

PubMed

Here, we describe a novel "switch-on" biosensor based on quinonyl glycosides functionalized quantum dots (QDs) for the specific targeting and imaging of transmembrane glycoprotein receptors on the surface of cancer cells. The design of the quinonyl glycosides lies in that the quinone moiety serves as a quencher of QDs and the glycoside moiety as a biospecific ligand for targeting a receptor. We observed that the quenched photoluminescence of the quinone glycosides functionalized QDs could be significantly recovered by a specific lectin that selectively binds to the glycosides clustering the QDs but was not affected by a panel of nonspecific lectins. Moreover, we determined that quinonyl galactoside functionalized QDs could optically image the asialoglycoprotein receptors of a hepatoma cell line in a target-specific manner. This system might provide new insights into the fabrication of photoluminogenic biosensors for the analysis of the universal ligand-receptor recognitions in nature. PMID:24803208

Ma, Wei; Liu, Hui-Ting; He, Xiao-Peng; Zang, Yi; Li, Jia; Chen, Guo-Rong; Tian, He; Long, Yi-Tao

2014-06-01

407

Stepwise synthesis of a GalNAc-containing cluster glycoside ligand of the asialoglycoprotein receptor.  

PubMed

A series of peptidylglycoside derivatives, including the tris(GalNAc-aminohexyl) glycoside of tyrosyl(glutamyl)-glutamate (1) which is known to have sub-nanomolar affinity for the asialoglycoprotein receptor (ASGPr), have been synthesized using the protected tetra-O-acetyl aminohexyl glycoside (9) of N-acetylgalactosamine. The N-succinyl derivative of 1 was also prepared, providing a derivative for bioconjugate formation via carboxyl activation of the glycopeptide. Use of the protected glycoside 9 affords synthetic intermediates with increased solubility in organic solvents that are easier to purify and use in subsequent synthetic manipulations in comparison with compounds containing unprotected glycosides. These synthetic procedures will be generally applicable to the preparation of related compounds to probe binding to the ASGPr and the use of these cluster glycosides as ligands for targeted delivery to the liver. PMID:8070972

Findeis, M A

1994-05-01

408

Quantitation of sweet steviol glycosides by means of a HILIC-MS/MS-SIDA approach.  

PubMed

Meeting the rising consumer demand for natural food ingredients, steviol glycosides, the sweet principle of Stevia rebaudiana Bertoni (Bertoni), have recently been approved as food additives in the European Union. As regulatory constraints require sensitive methods to analyze the sweet-tasting steviol glycosides in foods and beverages, a HILIC-MS/MS method was developed enabling the accurate and reliable quantitation of the major steviol glycosides stevioside, rebaudiosides A-F, steviolbioside, rubusoside, and dulcoside A by using the corresponding deuterated 16,17-dihydrosteviol glycosides as suitable internal standards. This quantitation not only enables the analysis of the individual steviol glycosides in foods and beverages but also can support the optimization of breeding and postharvest downstream processing of Stevia plants to produce preferentially sweet and least bitter tasting Stevia extracts. PMID:24206531

Well, Caroline; Frank, Oliver; Hofmann, Thomas

2013-11-27

409

Tissue and Cellular Localization of Tannins in Tunisian Dates (Phoenix dactylifera L.) by Light and Transmission Electron Microscopy.  

PubMed

A histological approach including light microscopy and transmission electron microscopy (TEM) was used to provide accurate information on the localization of condensed tannins in the edible tissues and in the stone of date fruits (Phoenix dactylifera L.). Light microscopy was carried out on fresh tissues after staining by 4-dimethylaminocinnamaldehyde (DMACA) for a specific detection of condensed tannins. Thus, whether under light microscopy or transmission electron microscopy (TEM), results showed that tannins are not located in the epidermis but more deeply in the mesocarp in the vacuole of very large cells. Regarding the stones, tannins are found in a specific cell layer located at 50 ?m from the sclereid cells of the testa. PMID:24987926

Hammouda, Hédi; Alvarado, Camille; Bouchet, Brigitte; Kalthoum-Chérif, Jamila; Trabelsi-Ayadi, Malika; Guyot, Sylvain

2014-07-16

410

Flavonol glycosides in wild and cultivated berries of three major subspecies of Hippophaë rhamnoides and changes during harvesting period  

Microsoft Academic Search

Flavonol glycosides are an important group of bioactive components of sea buckthorn (Hippophaë rhamnoides). The content and profile of flavonol glycosides of some major subspecies and most cultivars as well as the variation amongst the harvesting years and dates are largely unknown. This study investigated flavonol glycosides in wild berries of two major subspecies H. rhamnoides ssp. rhamnoides and ssp.

Baoru Yang; Teemu Halttunen; Olli Raimo; Keith Price; Heikki Kallio

2009-01-01

411

Micromolar concentrations of EGTA increase histamine secretion from mast cells treated with digitalis glycosides of different polarity  

Microsoft Academic Search

Histamine release from rat peritoneal mast cells induced by compound 48\\/80 (1 ?g\\/ml) after 90 min of preincubation in calcium — free medium is only 8.4%. Cardiotonic glycosides modify the secretion induced by compound 48\\/80: hydrophlic glycosides potentiate the secretion, and this potentiation decreases with increasing lipophility of the glycosides.

Ilonka Ferjan; F. Erjavec

1993-01-01

412

Identification of a novel flavonoid glycoside sulfotransferase in Arabidopsis thaliana.  

PubMed

The discovery of sulfated flavonoids in plants suggests that sulfation may play a regulatory role in the physiological functions of flavonoids. Sulfation of flavonoids is mediated by cytosolic sulfotransferases (SULTs), which utilize 3'-phosphoadenosine 5'-phosphosulfate (PAPS) as the sulfate donor. A novel SULT from Arabidopsis thaliana, designated AtSULT202B7 (AGI code: At1g13420), was cloned and expressed in Escherichia coli. Using various compounds as potential substrates, we demonstrated, for the first time, that AtSULT202B7 displayed sulfating activity specific for flavonoids. Intriguingly, the recombinant enzyme preferred flavonoid glycosides (e.g. kaempferol-3-glucoside and quercetin-3-glucoside) rather than their aglycone counterparts. Among a series of hydroxyflavones tested, AtSULT202B7 showed the enzymatic activity only for 7-hydroxyflavone. pH-dependency study showed that the optimum pH was relatively low (pH 5.5) compared with those (pH 6.0-8.5) previously reported for other isoforms. Based on the comparison of high performance (pressure) liquid chromatography (HPLC) retention times between sulfated kaempferol and the deglycosylated product of sulfated kaempferol-3-glucoside, the sulfation site in sulfated kaempferol-3-glucoside appeared to be the hydroxyl group of the flavonoid skeleton. In addition, by using direct infusion mass spectrometry, it was found that the sulfated product had one sulfonate group within the molecule. These results indicated that AtSULT202B7 functions as a flavonoid glycoside 7-sulfotransferase. PMID:24202284

Hashiguchi, Takuyu; Sakakibara, Yoichi; Shimohira, Takehiko; Kurogi, Katsuhisa; Yamasaki, Masao; Nishiyama, Kazuo; Akashi, Ryo; Liu, Ming-Cheh; Suiko, Masahito

2014-02-01

413

Recovering glycoside hydrolase genes from active tundra cellulolytic bacteria.  

PubMed

Bacteria responsible for cellulose hydrolysis in situ are poorly understood, largely because of the relatively recent development of cultivation-independent methods for their detection and characterization. This study combined DNA stable-isotope probing (DNA-SIP) and metagenomics for identifying active bacterial communities that assimilated carbon from glucose and cellulose in Arctic tundra microcosms. Following DNA-SIP, bacterial fingerprint analysis of gradient fractions confirmed isotopic enrichment. Sequenced fingerprint bands and clone library analysis of 16S rRNA genes identified active bacterial taxa associated with cellulose-associated labelled DNA, including Bacteroidetes (Sphingobacteriales), Betaproteobacteria (Burkholderiales), Alphaproteobacteria (Caulobacteraceae), and Chloroflexi (Anaerolineaceae). We also compared glycoside hydrolase metagenomic profiles from bulk soil and heavy DNA recovered from DNA-SIP incubations. Active populations consuming [(13)C]glucose and [(13)C]cellulose were distinct, based on ordinations of light and heavy DNA. Metagenomic analysis demonstrated a ?3-fold increase in the relative abundance of glycoside hydrolases in DNA-SIP libraries over bulk-soil libraries. The data also indicate that multiple displacement amplification introduced bias into the resulting metagenomic analysis. This research identified DNA-SIP incubation conditions for glucose and cellulose that were suitable for Arctic tundra soil and confirmed that DNA-SIP enrichment can increase target gene frequencies in metagenomic libraries. PMID:24983351

Pinnell, Lee J; Dunford, Eric; Ronan, Patrick; Hausner, Martina; Neufeld, Josh D

2014-07-01

414

Allosteric indicator displacement enzyme assay for a cyanogenic glycoside.  

PubMed

Indicator displacement assays (IDAs) represent an elegant approach in supramolecular analytical chemistry. Herein, we report a chemical biosensor for the selective detection of the cyanogenic glycoside amygdalin in aqueous solution. The hybrid sensor consists of the enzyme ?-glucosidase and a boronic acid appended viologen together with a fluorescent reporter dye. ?-Glucosidase degrades the cyanogenic glycoside amygdalin into hydrogen cyanide, glucose, and benzaldehyde. Only the released cyanide binds at the allosteric site of the receptor (boronic acid) thereby inducing changes in the affinity of a formerly bound fluorescent indicator dye at the other side of the receptor. Thus, the sensing probe performs as allosteric indicator displacement assay (AIDA) for cyanide in water. Interference studies with inorganic anions and glucose revealed that cyanide is solely responsible for the change in the fluorescent signal. DFT calculations on a model compound revealed a 1:1 binding ratio of the boronic acid and cyanide ion. The fluorescent enzyme assay for ?-glucosidase uses amygdalin as natural substrate and allows measuring Michaelis-Menten kinetics in microtiter plates. The allosteric indicator displacement assay (AIDA) probe can also be used to detect cyanide traces in commercial amygdalin samples. PMID:24123550

Jose, D Amilan; Elstner, Martin; Schiller, Alexander

2013-10-18

415

Angling for Uniqueness in Enzymatic Preparation of Glycosides  

PubMed Central

In the early days of biocatalysis, limitations of an enzyme modeled the enzymatic applications; nowadays the enzyme can be engineered to be suitable for the process requirements. This is a general bird’s-eye view and as such cannot be specific for articulated situations found in different classes of enzymes or for selected enzymatic processes. As far as the enzymatic preparation of glycosides is concerned, recent scientific literature is awash with examples of uniqueness related to the features of the biocatalyst (yield, substrate specificity, regioselectivity, and resistance to a particular reaction condition). The invention of glycosynthases is just one of the aspects that has thrust forward the research in this field. Protein engineering, metagenomics and reaction engineering have led to the discovery of an expanding number of novel enzymes and to the setting up of new bio-based processes for the preparation of glycosides. In this review, new examples from the last decade are compiled with attention both to cases in which naturally present, as well as genetically inserted, characteristics of the catalysts make them attractive for biocatalysis.

Trincone, Antonio

2013-01-01

416

Oleanane-type glycosides from Tremastelma palaestinum (L.) Janchen.  

PubMed

Three new oleanane-type glycosides, 1-3, were isolated from the whole plant of Tremastelma palaestinum (L.) Janchen, along with eight known triterpene glycosides. The structures of the new compounds were established as 3-O-[?-d-glucopyranosyl-(1?3)-?-l-rhamnopyranosyl-(1?3)-?-d-glucopyranosyl-(1?3)-?-l-rhamnopyranosyl-(1?2)-?-l-arabinopyranosyl]hederagenin (1), 3-O-[?-d-glucopyranosyl-(1?3)-?-l-rhamnopyranosyl-(1?3)-?-d-glucopyranosyl-(1?3)-?-l-rhamnopyranosyl-(1?2)-?-l-arabinopyranosyl]hederagenin 28-O-?-d-glucopyranosyl-(1?6)-?-d-glucopyranosyl ester (2), and 3-O-[?-l-rhamnopyranosyl-(1?3)-?-d-glucopyranosyl-(1?3)-?-l-rhamnopyranosyl-(1?2)-?-l-arabinopyranosyl]oleanolic acid 28-O-?-d-glucopyranosyl-(1?6)-?-d-glucopyranosyl ester (3) by using 1D- and 2D-NMR techniques and mass spectrometry. This is the first report on the phytochemical investigation of a species belonging to Tremastelma genus. PMID:24634070

?enel, Gökhan; Gülcemal, Derya; Masullo, Milena; Piacente, Sonia; Karay?ld?r?m, Tamer

2014-03-01

417

Oleanane type glycosides from Paronychia anatolica subsp. balansae.  

PubMed

Four new oleanane-type triterpene glycosides were isolated from the methanol extract of the roots of Paronychia anatolica subsp. balansae along with three known oleanane-type triterpene glycosides. Structures of the new compounds were established as 3-O-?-D-glucuronopyranosyl-28-O-[?-L-rhamnopyranosyl-(1?2)-?-D-quinovopyranoside] zahnic acid, 3-O-?-D-glucuronopyranosyl-28-O-[?-D-xylopyranosyl-(1?4)-?-L-rhamnopyranosyl-(1?2)-?-D-quinovopyranoside] zahnic acid, 3-O-?-D-glucuronopyranosyl-28-O-[?-L-arabinofuranosyl-(1?2)-?-D-quinovopyranoside] zahnic acid, 28-O-[?-L-rhamnopyranosyl-(1?4)-?-D-glucopyranosyl-(1?6)-?-D-glucopyranosyl]-medicagenic acid, by using 1D and 2D-NMR techniques and mass spectrometry. The cytotoxic activity of the isolated compounds was evaluated against a small panel of cancer cell lines including human breast cancer (MCF-7), human lung adenocarcinoma (A549) and human leukemia (U937) cell lines. PMID:24321579

Gülcemal, Derya; Masullo, Milena; Alanku?-Çal??kan, Özgen; Piacente, Sonia

2014-01-01

418

Glycosidated phospholipids - a promising group of anti-tumour lipids.  

PubMed

Synthetic alkylphospholipids (APLs), exhibit similarity to the platelet-activating factor (PAF). These compounds have antiproliferative effects on tumour cells and can therefore be regarded as a new class of drugs. Unlike classic cytostatic agents, synthetic alkylphospholipids do not interfere with the DNA or the mitotic spindle apparatus. Instead, due to their aliphatic character, alkylphospholipids accumulate in cell membranes, where they have an impact on lipid metabolism and lipid-dependent signalling pathways which leads to inhibition of proliferation and induction of apoptosis in malignant cells. Normal cells remain unaffected by these compounds. Glycosidated phospholipids, are a novel class of alkylphospholipids, in which carbohydrates or carbohydrate-related molecules are introduced in the chemical lead of PAF. These hybrid alkylphospholipids also exhibit anti-proliferative capacity. Furthermore, members of this subfamily also modulate cell adhesion, differentiation, apoptosis and migration of tumour cells. Among the members of this group, Inositol-C2-platelet-activating factor (Ino-C2-PAF) is the most effective compound developed so far. Recently, we also showed that Ino-C2-PAF exhibited the strongest impact on the gene expression levels of immortalised keratinocytes in comparison to edelfosine and another glycosidated alkylphospholipid, Glucose-platelet-activating factor (Glc-PAF). Furthermore, Ino-C2-PAF reduced the expression of genes encoding proteins associated with inflammation and the innate and acquired immune responses. PMID:24628240

Semini, Geo; Hildmann, Annette; von Haefen, Clarissa; Danker, Kerstin

2014-05-01

419

Steviol glycosides modulate glucose transport in different cell types.  

PubMed

Extracts from Stevia rebaudiana Bertoni, a plant native to Central and South America, have been used as a sweetener since ancient times. Currently, Stevia extracts are largely used as a noncaloric high-potency biosweetener alternative to sugar, due to the growing incidence of type 2 diabetes mellitus, obesity, and metabolic disorders worldwide. Despite the large number of studies on Stevia and steviol glycosides in vivo, little is reported concerning the cellular and molecular mechanisms underpinning the beneficial effects on human health. The effect of four commercial Stevia extracts on glucose transport activity was evaluated in HL-60 human leukaemia and in SH-SY5Y human neuroblastoma cells. The extracts were able to enhance glucose uptake in both cellular lines, as efficiently as insulin. Our data suggest that steviol glycosides could act by modulating GLUT translocation through the PI3K/Akt pathway since treatments with both insulin and Stevia extracts increased the phosphorylation of PI3K and Akt. Furthermore, Stevia extracts were able to revert the effect of the reduction of glucose uptake caused by methylglyoxal, an inhibitor of the insulin receptor/PI3K/Akt pathway. These results corroborate the hypothesis that Stevia extracts could mimic insulin effects modulating PI3K/Akt pathway. PMID:24327825

Rizzo, Benedetta; Zambonin, Laura; Angeloni, Cristina; Leoncini, Emanuela; Dalla Sega, Francesco Vieceli; Prata, Cecilia; Fiorentini, Diana; Hrelia, Silvana

2013-01-01

420

Steviol Glycosides Modulate Glucose Transport in Different Cell Types  

PubMed Central

Extracts from Stevia rebaudiana Bertoni, a plant native to Central and South America, have been used as a sweetener since ancient times. Currently, Stevia extracts are largely used as a noncaloric high-potency biosweetener alternative to sugar, due to the growing incidence of type 2 diabetes mellitus, obesity, and metabolic disorders worldwide. Despite the large number of studies on Stevia and steviol glycosides in vivo, little is reported concerning the cellular and molecular mechanisms underpinning the beneficial effects on human health. The effect of four commercial Stevia extracts on glucose transport activity was evaluated in HL-60 human leukaemia and in SH-SY5Y human neuroblastoma cells. The extracts were able to enhance glucose uptake in both cellular lines, as efficiently as insulin. Our data suggest that steviol glycosides could act by modulating GLUT translocation through the PI3K/Akt pathway since treatments with both insulin and Stevia extracts increased the phosphorylation of PI3K and Akt. Furthermore, Stevia extracts were able to revert the effect of the reduction of glucose uptake caused by methylglyoxal, an inhibitor of the insulin receptor/PI3K/Akt pathway. These results corroborate the hypothesis that Stevia extracts could mimic insulin effects modulating PI3K/Akt pathway.

Rizzo, Benedetta; Zambonin, Laura; Leoncini, Emanuela; Vieceli Dalla Sega, Francesco; Prata, Cecilia; Fiorentini, Diana; Hrelia, Silvana

2013-01-01

421

Adult cardiac anaesthesia.  

PubMed

The widespread increase in adult cardiac surgery over the last decade has meant that many more junior anaesthetists have become involved in the management of anaesthesia for cardiac surgery before they have taken the final part of the FRCA examination. Although cardiac anaesthesia is still a specialized area, FRCA candidates are expected to have a working knowledge of the principles involved. PMID:8826042

Freeman, J M; Clutton-Brock, T H

422

Interspecific differences in tannin intakes of forest-dwelling rodents in the wild revealed by a new method using fecal proline content.  

PubMed

Mammalian herbivores adopt various countermeasures against dietary tannins, which are among the most widespread plant secondary metabolites. The large Japanese wood mouse Apodemus speciosus produces proline-rich salivary tannin-binding proteins in response to tannins. Proline-rich proteins (PRPs) react with tannins to form stable complexes that are excreted in the feces. Here, we developed a new method for estimating the tannin intake of free-living small rodents, by measuring fecal proline content, and applied the method to a field investigation. A feeding experiment with artificial diets containing various levels of tannic acid revealed that fecal proline content was clearly related to dietary tannin content in three species (A. speciosus, Apodemus argenteus, and Myodes rufocanus). We then used fecal proline content to estimate the tannin intakes of these three forest-dwelling species in a forest in Hokkaido. In the autumn, estimated tannin intakes increased significantly in the Apodemus species, but not in M. rufocanus. We speculated that an increase in tannin intake during autumn may result from consumption of tannin-rich acorns. This hypothesis was consistent with population fluctuation patterns of the three species, which were well-synchronized with acorn abundance for the Apodemus species but not for M. rufocanus. PMID:22161223

Shimada, Takuya; Nishii, Eriko; Saitoh, Takashi

2011-12-01

423

Effect of tannins and phenolic extracts from plant roots on the production of cellulase and polygalacturonase by Dematophora necatrix  

Microsoft Academic Search

Dematophora necatrix, the causal agent of the white root rot disease in plants, produced large amounts of cellulase (Cx) and very small amounts\\u000a of polygalacturonase (PG). Both tannins (100 mg\\/l) and phenols (200 mg\\/l) extracted from roots of plants showing resistance\\u000a to the disease decreased Cx productionin vitro. PG production was affected only by tannin extracts. Exposure of the fungus

A. Sztejnberg; H. Azaizia; N. Lisker

1989-01-01

424

The Swarming Motility of Pseudomonas aeruginosa Is Blocked by Cranberry Proanthocyanidins and Other Tannin-Containing Materials?  

PubMed Central

Bacterial motility plays a key role in the colonization of surfaces by bacteria and the subsequent formation of resistant communities of bacteria called biofilms. Derivatives of cranberry fruit, predominantly condensed tannins called proanthocyanidins (PACs) have been reported to interfere with bacterial adhesion, but the effects of PACs and other tannins on bacterial motilities remain largely unknown. In this study, we investigated whether cranberry PAC (CPAC) and the hydrolyzable tannin in pomegranate (PG; punicalagin) affected the levels of motilities exhibited by the bacterium Pseudomonas aeruginosa. This bacterium utilizes flagellum-mediated swimming motility to approach a surface, attaches, and then further spreads via the surface-associated motilities designated swarming and twitching, mediated by multiple flagella and type IV pili, respectively. Under the conditions tested, both CPAC and PG completely blocked swarming motility but did not block swimming or twitching motilities. Other cranberry-containing materials and extracts of green tea (also rich in tannins) were also able to block or impair swarming motility. Moreover, swarming bacteria were repelled by filter paper discs impregnated with many tannin-containing materials. Growth experiments demonstrated that the majority of these compounds did not impair bacterial growth. When CPAC- or PG-containing medium was supplemented with surfactant (rhamnolipid), swarming motility was partially restored, suggesting that the effective tannins are in part acting by a rhamnolipid-related mechanism. Further support for this theory was provided by demonstrating that the agar surrounding tannin-induced nonswarming bacteria was considerably less hydrophilic than the agar area surrounding swarming bacteria. This is the first study to show that natural compounds containing tannins are able to block P. aeruginosa swarming motility and that swarming bacteria are repelled by such compounds.

O'May, Che; Tufenkji, Nathalie

2011-01-01

425

Effect of condensed tannins extracted from four forages on the viability of the larvae of deer lungworms and gastrointestinal nematodes.  

PubMed

The inhibitory activity of condensed tannins extracted from four forage legume plants were evaluated by using a larval migration inhibition assay. The first (L1) and third (L3) stages of deer lungworm (Dictyocaulus viviparus), and the third stage (L3) of deer gastrointestinal nematodes were incubated with tannins extracted from Lotus pedunculatus, Lotus corniculatus, sulla (Hedysarum coronarium) and sainfoin (Onobrychus viciifolia). The tannins extracted from all the forages had inhibitory activity as measured by their ability to paralyse the larvae and inhibit them from passing through sieves. At the highest concentration used (1200 microg/ml) the tannins extracted from sainfoin had the highest activity against ensheathed L1 lungworm larvae (58 per cent), followed by L. pedunculatus (45 per cent), sulla (42 per cent) and L. comiculatus (35 per cent) when the larvae were incubated at 37 degrees C. The same trend, but with lower activities, was observed when the larvae were incubated at 22 degrees C. Anthelmintic activity against L3 lungworm larvae was evaluated by measuring the death rate of ensheathed L3 larvae after incubation with condensed tannins for two, 24 and 48 hours at room temperature (22 degrees C). The death rate was significantly higher (P<0.001) after 48 hours incubation than after two hours or 24 hours, and significantly higher (P<0.001) after 24 hours than after two hours incubation. Condensed tannins from sainfoin had the highest inhibitory activity followed by L. pedunculatus, sulla and L. comiculatus. The tannins from sainfoin also had the highest activity against L3 larvae of gastrointestinal nematodes, followed by L. pedunculatus, sulla and L. comiculatus. Exsheathed larvae of gastrointestinal nematodes were significantly more susceptible to the action of the tannins than ensheathed larvae. PMID:10955893

Molan, A L; Hoskin, S O; Barry, T N; McNabb, W C

2000-07-01

426

Plant tannins inhibit the induction of aberrant crypt foci and colonic tumors by 1,2-dimethylhydrazine in mice.  

PubMed

We have shown that naturally occurring tannins possess antitumor promotion activity in mouse skin. In the present investigation, we studied the ability of a hydrolyzable tannin, gallotannin (GT), and a condensed tannin extracted from red alder (RA) bark to inhibit 1,2-dimethylhydrazine (DMH)-induced colonic aberrant crypt foci (ACF) and tumors in Balb/c mice. In addition, we determined the ability of GT to inhibit the proliferation and to induce apoptosis in a human colon cancer cell line (T-84). Mice were given tannins by intraperitoneal injections, by gavage, or in drinking water before treatment with DMH for 24 weeks. Alternatively, mice were given tannins by intraperitoneal injection or gavage for only 2 weeks before DMH administration, then tannin administration was discontinued and mice were treated with DMH for 24 weeks. The multiplicity, size, and distribution of ACF and tumors were significantly inhibited by GT and RA in the above treatment regimens. The most effective treatments included GT by gavage, RA bark extract by intraperitoneal injection, and either tannin dissolved in drinking water. Extent of inhibition of ACF and tumors was gender independent. In cell culture experiments, GT treatment for three days inhibited the growth of T-84 cells, with a concentration resulting in half-maximal inhibition estimated to be 20 micrograms/ml. The treatment was not cytotoxic to cells at 1-40 micrograms/ml. Interestingly, at 10 micrograms/ml, GT induced apoptosis in T-84 cells as determined by the Hoechst DNA staining technique. Collectively, these findings support a potential role for tannins as chemopreventive agents against colon cancer. PMID:11588891

Gali-Muhtasib, H U; Younes, I H; Karchesy, J J; el-Sabban, M E

2001-01-01

427

Modulation of Proline-Rich Protein Biosynthesis in Rat Parotid Glands by Sorghums with High Tannin Levels  

Microsoft Academic Search

Feeding of sorghum with a high level of tannin (high-tannin sorghum) to rats caused changes in gene expression in parotid glands similar to isoproterenol treatment. Within 3 days the parotid glands were enlarged about 3-fold and a series of proline-rich proteins were increased about 12-fold. Unlike isoproterenol treatment, no changes were observed in the submandibular glands, and a Mr 220,000

Haile Mehansho; Ann Hagerman; Scott Clements; Larry Butler; John Rogler; Don M. Carlson

1983-01-01

428

In vivo assessment of the ability of condensed tannins to interfere with the digestibility of plant protein in sheep  

Microsoft Academic Search

To assess the effect of condensed tannin (CT) astringency on the digestibility of protein post-ruminally, CT were purified from four types (accessions) of Mulga (Acacia aneura), and a Leucaena pallida and dosed into sheep as complexes with 15N-plant protein (tannin–protein complexes, TPC), together with an indigestible marker, chromium-EDTA (Cr-EDTA). Each CT treatment dose comprised 12mg CT, 10mg 15N-protein, and 2.77mg

S. M. Andrabi; M. M. Ritchie; C. Stimson; A. Horadagoda; M. Hyde; D. M. McNeill

2005-01-01

429

Studies on Emblica officinalis Derived Tannins for Their Immunostimulatory and Protective Activities against Coccidiosis in Industrial Broiler Chickens  

PubMed Central

The present study reports the effect of Emblica officinalis (EO) derived tannins on humoral immune responses and their protective efficacy against Eimeria infection in chickens. Tannins were extracted from EO and characterized by HPLC. EO derived tannins (EOT) and commercial tannins (CT) were orally administered in broiler chicks in graded doses for three consecutive days, that is, 5th-7th days of age. On day 14 after administration of tannins, humoral immune response was detected against sheep red blood cells (SRBCs) by haemagglutination assay. Protective efficacy of tannins was measured against coccidial infection, induced by Eimeria species. Results revealed higher geomean titers against SRBCs in chickens administered with EOT as compared to those administered with CT and control group. Mean oocysts per gram of droppings were significantly lower (P < 0.05) in EOT administered chickens as compared to control group. Lesion scoring also showed the lowest caecal and intestinal lesion score of mild to moderate intensity in chickens administered with EOT. Further, significantly higher (P < 0.05) daily body weight gains and antibody titers were detected in EOT administered chickens as compared to those of CT administered and control groups. EOT showed the immunostimulatory properties in broilers and their administration in chickens boost the protective immunity against coccidiosis.

Kaleem, Qari Muhammad; Akhtar, Masood; Awais, Mian Muhammad; Saleem, Muhammad; Zafar, Muddassar; Iqbal, Zafar; Muhammad, Faqir

2014-01-01

430

Evaluation of the content variation of anthraquinone glycosides in rhubarb by UPLC-PDA  

PubMed Central

Background Rhubarb is an important Chinese medicinal herb with a long history of over 2000 years and has been commonly used as a laxative. It is the radix and rhizome of Rheum officinale Baill., R. palmatum L. and R. tanguticum Maxim, all of which are mainly distributed in a broad region in the Tibetan plateau. Anthraquinone glycosides are a series of major active ingredients found in all three species. They are key intermediates in the anthraquinone secondary metabolism and the sennnoside biosynthesis. The variation of the anthraquinone glycoside content in rhubarb in response to specific factors remains an attractive topic. Results A simple and sensitive Ultra Performance Liquid Chromatography with Photo-Diode Array (UPLC-PDA) detector was developed for the simultaneous determination of six anthraquinone glycosides in rhubarb, i.e., aloeemodin-8-O-glucoside, rhein-8-O-glucoside, chrysophanol-1-O-glucoside, emodin-1-O-glucoside, chrysophanol-8-O-glucoside, emodin-8-O-glucoside. Twenty-seven batches from three species were submitted to the multi-component analysis. The results showed that the anthraquinone glycoside content varied significantly even within the same species. The results showed that the anthraquinone glycoside content varied significantly within the same species but not between different species. The PCA and content analysis results confirmed that the plant species has no obvious effect on the content variation. Neither was any significant correlation observed between the anthraquinone glycoside content and the geographic distribution of the rhubarb. Through correlational analysis, altitude was found to be the main factor that affects the anthraquinone glycoside content in rhubarb. Rhubarb grown at higher altitude has higher anthraquinone glycoside content. Conclusions This work provides a rapid, sensitive and accurate UPLC-PDA method for the simultaneous determination of six anthraquinone glycosides in rhubarb. The anthraquinone glycoside content varied significantly within the same species. The relationship of the anthraquinone glycoside content with plant species, geographic distribution and altitude were studied using correlational analysis, principal component analysis and spatial autocorrelation analysis through SPSS and ArcGIS. Plant species and geographic distribution were found not to affect the content of the six anthraquinone glycosides in rhubarb. The variations in the anthraquinone glycoside content were primarily due to the different altitude where the plant was grown.

2013-01-01

431

Effect of condensed tannins on egg hatching and larval development of Trichostrongylus colubriformis in vitro.  

PubMed

The effects of condensed tannins extracted from seven forages on the viability of the eggs and first stage (L1) larvae of the sheep nematode Trichostrongylus colubriformis were evaluated in in vitro assays. The extracts of condensed tannins were obtained from Lotus pedunculatus (LP), Lotus corniculatus (LC), sulla (Hedysarum coronarium), sainfoin (Onobrychus viciifolia), Dorycnium pentaphylum (DP), Dorycnium rectum (DR) and dock (Rumex obtusifolius). Extracts containing 200 to 500 microg/ml reduced the proportion of eggs that hatched. The larval development assay was used to evaluate the effect of the extracts on the development of either eggs or L1 larvae to L3 infective larvae. Development was allowed to proceed for seven days by which time the larvae in control incubations had reached the infective L3 stage. Extracts containing 200 microg/ml from LP, DP, DR or dock prevented egg development, and only 11, 8 and 2 per cent of the eggs developed to L3 larvae with extracts from LC, sulla and sainfoin, respectively. When the concentration was 400 microg/ml no eggs developed to L3 larvae. The addition of the extracts after hatching also inhibited the development of L1 to L3 larvae; 200 microg/ml extracted from LP, LC, sulla, sainfoin, DP, DR and dock resulted in only 14, 18, 17, 15, 14, 16 and 4 per cent of L1 larvae developing to the L3 stage compared with 85 per cent for controls, and 400 microg/ml further reduced the development of L1 larvae. Statistical analyses showed that when the extracts were added before hatching they were significantly (P<0.001) more effective at inhibiting the larval development than when they were added after hatching. The condensed tannins from dock had the greatest inhibitory effect on egg development followed by the tannins from DR, sainfoin, DP, LP, sulla and LC. PMID:11837588

Molan, A L; Waghorn, G C; McNabb, W C

2002-01-19

432

Characterization of condensed tannins from Lotus species by thiolytic degradation and electrospray mass spectrometry  

Microsoft Academic Search

The properties of condensed tannins (CT) from Lotus corniculatus and L. pedunculatus (also known as L. uliginosus) depend on their structure in terms of monomer units, their mean degree of polymerisation (mDP) and the linkage-type between flavan-3-ol units with a considerable range of structural variation. To ascertain the identity of the individual units that make up the CT, the polymer

L. P. Meagher; S. Sivakumaran; M. H. Tavendale; K. Fraser

2004-01-01

433

Activity of tannins from Stryphnodendron adstringens on Cryptococcus neoformans: effects on growth, capsule size and pigmentation  

PubMed Central

Background Stryphnodendron adstringens (Mart.) Coville, Leguminosae, also known in Brazil as barbatimão, is rich in tannins and many flavan-3-ols and proanthocyanidins such as prodelphinidins and prorobinetinidins. Previous studies have demonstrated several pharmacological properties of tannins from barbatimão, including anti-candidal activity. Methods The antifungal activity of proanthocyanidin polymeric tannins from Stryphnodendron adstringens (subfraction F2.4) was evaluated against three strains of Cryptococcus neoformans with different capsule expressions, using the broth microdilution technique, light microscopy and transmission electron microscopy. The effect of subfraction F2.4 on C. neoformans and melanoma mammalian cells pigmentation was also evaluated. Results Although susceptibility assays revealed MIC values quite similar (between 2.5 and 5.0 ?g/ml), analyses of MFC values revealing that the acapsular mutant Cap 67 was more susceptible to be killed by the subfraction F2.4 (MFC = 20 ?g/ml) than the two tested capsular strains (T1-444 and ATCC 28957) (MFC > 160 ?g/ml). Optical and electron microscopy experiments revealed relevant alterations in cell shape and size in all strains treated with 1 and 2.5 ?g/ml of subfraction F2.4. Capsule size of the capsular strains decreased drastically after subfraction F2.4 treatment. In addition, ultrastructural alterations such as cell wall disruption, cytoplasm extraction, mitochondria swelling, increase in the number of cytoplasmic vacuoles and formation of membranous structures in the cytoplasm were also observed in treated yeasts. Incubation with subfraction F2.4 also decreased C. neoformans pigmentation, however, did not interfere in melanization of B16F10 mammalian cells. Conclusion Our data indicate that tannins extracted from S. adstringens interfered with growth, capsule size and pigmentation, all important virulence factors of C. neoformans, and may be considered as a putative candidate for the development of new antifungal agents.

Ishida, Kelly; Rozental, Sonia; de Mello, Joao Carlos Palazzo; Nakamura, Celso Vataru

2009-01-01

434

Antibacterial activity of tannin constituents from Phaseolus vulgaris, Fagoypyrum esculentum, Corylus avellana and Juglans nigra.  

PubMed

Tannins were fractionated from acetonic extract preparations of phenolic compounds from Phaseolus vulgaris, Fagoypyrum esculentum, Corylus avellana and Juglans nigra. Wide variations in antibacterial activities ranging from MICs of 62.5 to 500 microg/ml were apparent. Of particular note was a relatively high level of activity (62.5 to 125 microg/ml) for all extracts against Listeria monocytogenes. PMID:18325686

Amarowicz, Ryszard; Dykes, Gary A; Pegg, Ronald B

2008-04-01

435

Effect of tannin extract against Pseudomonas aeruginosa producing metallo beta-lactamase.  

PubMed

Carbapenems are the most potent beta-lactam agents with a broad-spectrum activity against Gram-negative and Gram-positive bacteria. They are stable in the presence of penicillinases and cephalosporinases. This study was focused on frequency of metallo beta- lactamase (MBL) among Pesudomonas aeruginosa strains isolated in patients with urinary tract infection, effect of tannin against PA positive strains which produced blaVIM or blaIMP and both of these genes (Species). Detection of MBL was performed by phonotypic and genotypic methods. Tannin extract was tested against P. aeruginosa producing MBL. During the study period, 240 P. aeruginosa isolates were identified. Among them 64 (26.6 percent) isolates were imipenem non-susceptible and confirmed by imipenem/EDTA. Our results revealed that the growth of blaVIM positive P. aeruginosa inhibited at 15 microg/ml concentration. The experiment repeated for blaIMP-positive P. aeruginosa and P. aeruginosa which harbored blaIMP and blaVIM, the results showed 35 microg/ml was the best concentration for inhibition of P. aeruginosa-positive blaIMP and also P. aeruginosa blaIMP and blaVIM. In conclusion, tannin was effective against P. aeruginosa producing blaVIM and blaIMP and both of them so it can be substituted with common antibiotics. The result showed significantly P. aeruginosa-harbored blaIMP was more responsible for imipenem resistance than P. aeruginosa-positive blaVIM. Interestingly, tannin was more effective against MBL-P. aeruginosa in comparison with current antibiotics. PMID:22824750

Ghafourian, S; Mohebi, R; Sekawi, Z; Raftari, M; Neela, V; Ghafourian, E; Aboualigalehdari, E; Rahbar, M; Sadeghifard, N

2012-01-01

436

Tannin acyl hydrolase (EC 3.1.1.20) activity of Aspergillus, Penicillium, Fusarium and Trichoderma  

Microsoft Academic Search

A spectrophotometric method to determine gallic acid, residual gallotannin and tannin acyl hydrolase (EC 3.1.1.20) activity during microbial hydrolysis of pentagalloyl glucose is described. The following equations have been developed to estimate gallotannin and gallic acid in the incubation medium by absorbance measurements at two different wavelengths: concentration of gallotannin (µg ml-1)=34.41 (A293.8)-6.98 (A254.6); concentration of gallic acid (µg ml-1)=21.77

B. Bajpai; S. Patil

1996-01-01

437

Microbial transformation of tannin-rich substrate to gallic acid through co-culture method  

Microsoft Academic Search

Modified solid-state fermentation (MSSF) of tannin-rich substrate yielding tannase and gallic acid was carried out using a co-culture of the filamentous fungi, Rhizopus oryzae (RO IIT RB-13, NRRL 21498) and Aspergillus foetidus (GMRB013 MTCC 3557). Powdered fruits of Terminalia chebula and powdered pod cover of Caesalpinia digyna was used in the process and the different process parameters for maximum production

Rintu Banerjee; Gargi Mukherjee; Krushna Chandra Patra

2005-01-01

438

Effects of viscosity on the bitterness and astringency of grape seed tannin  

Microsoft Academic Search

To examine the separate effects of viscosity and sweetness on astringency, aqueous solutions of grape seed tannin (GST) were thickened with carboxymethyl cellulose (CMC) from 2 to 45 cP (experiment 1) or sweetened with 0 to 1.8 gL aspartame (experiment 2). Trained subjects continuously rated astringency and bitterness in duplicate. Subjects were categorized by the salivary flow induced by citric

Andrew K. Smith; Helen June; Ann C. Noble

1996-01-01

439

Aggregation of grape seed tannins in model wine—effect of wine polysaccharides  

Microsoft Academic Search

The ability of grape seed tannins to aggregate into colloidal-size range particles in a model wine was evidenced by DLS. In the present experimental conditions, they formed aggregates with mean apparent diameters increasing with time. These mean apparent diameters were shown to increase with the concentration (from 0.5 to 2g\\/l) and with the mean degree of polymerisation (mDP from 1.7

Valérie Riou; Aude Vernhet; Thierry Doco; Michel Moutounet

2002-01-01

440

Influence of Myriophyllum spicatum-derived tannins on gut microbiota of its herbivore Acentria ephemerella.  

PubMed

The submerged living larvae of Acentria ephemerella were fed in the laboratory with either M. spicatum or Potamogeton perfoliatus, two of their host plants. Larvae exhibited a reduced growth when fed M. spicatum, a freshwater angiosperm that contains high concentrations of tannins, secondary metabolites known for their herbivore-deterrent and antimicrobial properties. In this study, we investigated the influence of food-derived tannins on gut microbiota. Bacterial densities in the guts did not differ between the food regimes, ranging from 2.8 to 13.3 x 10(6) cells per gut. Gut bacteria were characterized with cultivation techniques and subsequent identification of the strains by molecular methods. We isolated 17 bacterial strains belonging to all subdivisions, i.e., we identified alpha-, beta-, and gamma-proteobacteria, Cytophyaga/Flavobacteria (CF) and several Gram-positive bacteria. All except one Gram-positive strain were found in the guts of larvae fed with P. perfoliatus. Gram-positive bacteria and bacteria of the CF cluster were more sensitive to polyphenol-containing extracts of M. spicatum in an agar diffusion assay than strains of the alpha- or gamma-proteobacteria subdivision. Our results suggest an influence of food-derived tannins on gut microbiota in A. ephemerella. PMID:12474899

Walenciak, Oliver; Zwisler, Walter; Gros, Elisabeth M

2002-10-01