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1

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

2

Merremins A-G, Resin Glycosides from Merremia hederacea with Multidrug Resistance Reversal Activity.  

PubMed

Five new pentasaccharide resin glycosides, named merremins A-E (1-5), two new pentasaccharide resin glycoside methyl esters, named merremins F and G (6, 7), and four known resin glycosides, murucoidin IV, murucoidin V, stoloniferin IV, and murucoidin XVII, were obtained from the aerial parts of Merremia hederacea. This is the first report of resin glycosides obtained from M. hederacea. In addition, the new compounds can be divided into three types: those possessing an 18-membered ring (1-4), compound 5 with a 20-membered ring, and those with an acyclic core (6, 7). Furthermore, the different types of resin glycosides were evaluated for their multidrug resistance reversal activities. Compounds 1, 5, 6, and murucoidin V were noncytotoxic and enhanced the cytotoxicity of vinblastine by 2.3-142.5-fold at 25 ?M. Compound 5 and murucoidin V, with 20-membered rings, were more active than compound 1, with an 18-membered ring. PMID:25310730

Wang, Wen-Qiong; Song, Wei-Bin; Lan, Xiao-Jing; Huang, Min; Xuan, Li-Jiang

2014-10-24

3

Quantitative Determination of Digitalis Glycosides in Digitalis Purpurea Leaves by Reversed-Phase Thin-Layer Chromatography  

Microsoft Academic Search

A densitometric reversed-phase thin-layer chromatographic(RP-TLC) method for the determination of digitalis glycosides in Digitalis purpurea leaves has been developed. The procedure involves extraction of dry leaf powder with ethanol\\/chloroform (2:1) and clean-up by Sep-Pak cartridges prior to RP-TLC analysis. RP-TLC was performed on an octadecylsilyl bonded silica gel plate, using a developing solvent of acetonitrile\\/0.5 M NaCl(1 : 1) for

Youichi Fujii; Yukari Ikeda; Mitsuru Yamazaki

1990-01-01

4

Temperature requirements for floral development of herbaceous peony cv. ‘Sarah Bernhardt’  

Microsoft Academic Search

The temperature requirements of peony during the various stages of its annual growing cycle were studied with the ultimate aim of enhancing early forcing and improving profitability. The immediate objective was to study the effects of chilling and subsequent growth conditions on plant development and flowering of ‘Sarah Bernhardt’, one of the most popular cultivars of herbaceous peony. Under our

Rina Kamenetsky; Amalia Barzilay; Amnon Erez; Abraham H Halevy

2003-01-01

5

The impact of sewage sludge compost on tree peony growth and soil microbiological, and biochemical properties.  

PubMed

In order to assess the suitability of sludge compost application for tree peony (Paeonia suffruticosa)-soil ecosystems, we determined soil microbial biomass C (Cmic), basal respiration (Rmic), enzyme activities, and tree peony growth parameters at 0-75% sludge compost amendment dosage. Soil Cmic, Rmic, Cmic as a percent of soil organic C, enzyme (invertase, urease, proteinase, phosphatase, polyphenoloxidase) activities, and plant height, flower diameter, and flower numbers per plant of tree peony significantly increased after sludge compost amendment; however, with the increasing sludge compost amendment dosage, a decreasing trend above 45% sludge compost amendment became apparent although soil organic C, total Kjeldahl N, and total P always increased with the sludge compost amendment. Soil metabolic quotient first showed a decreasing trend with the increasing sludge compost application in the range of 15-45%, and then an increasing trend from compost application of 45-75%, with the minimum found at compost application of 45%. As for the diseased plants, 50% of tree peony under the treatment without sludge compost amendment suffered from yellow leaf disease of tree peony, while no any disease was observed under the treatments with sludge compost application of 30-75%, which showed sludge compost application had significant suppressive effect on the yellow leaf disease of tree peony. This result convincingly demonstrated that ?45% sludge compost application dosage can take advantage of beneficial effect on tree peony growth and tree peony-soil ecosystems. PMID:23800593

Xue, Dong; Huang, Xiangdong

2013-10-01

6

Development and validation of a reversed-phase high-performance liquid chromatography method for routine identification and purity assessment of high-purity steviol glycoside sweeteners.  

PubMed

The widespread application of stevia-based sweeteners in food products has resulted in the need for reliable analytical methods for measuring the purity and identity of high-purity steviol glycoside ingredients. The objective of this research was to develop and validate a new reversed-phase separation method capable of separating and quantifying nine steviol glycosides present in typical high-purity stevia extract ingredients. Results of the study established the linearity of the method at a correlation factor of 1.000 for the two major components and other minor components of this food ingredient. Method accuracy values were in the range of 99.1-100.9%. The percent relative standard deviation for six independent assay determinations was 1.0%. The method was determined to be robust for minor changes in column temperature, initial acetonitrile content, flow rate, and wavelength. The validated high-performance liquid chromatography method was found to be suitable to be included by USP as a Food Chemicals Codex compendial standard for steviol glycosides. PMID:24443893

Bililign, Tsion; Moore, Jeffrey C; Tan, Shane; Leeks, Allan T

2014-02-12

7

Isolation and purification of iridoid glycosides from Gardenia jasminoides Ellis by isocratic reversed-phase two-dimensional preparative high-performance liquid chromatography with column switch technology.  

PubMed

A two-dimensional column-switching system without sample loop trapping, where two columns were switched directly via a six-port two-position switching valve, was successfully applied for the first time to the isolation and purification of six iridoid glycosides including geniposide, gardenoside, shanzhiside, scandoside methyl ester, deacetyl-asperulosidic acid methyl ester and genipin-1-beta-D-gentiobioside from Gardenia jasminoides Ellis, a plant used in the traditional Chinese medicine. The introduction of the six-port switching valve instead of sample loop assured 100% recovery from the first dimension to the second, and the injection volumes of the second dimension could reach 20 ml. In this mode of operation, the sample size of the two-dimensional approach was more than 1.3 times that of conventional gradient methods with even less solvent consumption. And the simultaneous operations of the two dimensions allowed the cycle time to be less than 19 min, compared with that (90 min) in the gradient elution single-dimension mode of operation. All of the six isolated iridoid glycosides were isolated at high purities of over 99% with approximately 96% recoveries. PMID:17851143

Zhou, Tingting; Zhao, Weiquan; Fan, Guorong; Chai, Yifeng; Wu, Yutian

2007-10-15

8

Not only dopamine D2 receptors involved in Peony-Glycyrrhiza Decoction, an herbal preparation against antipsychotic-associated hyperprolactinemia.  

PubMed

Clinical studies have demonstrated the effectiveness of an herbal preparation called Peony-Glycyrrhiza Decoction (PGD) in alleviating antipsychotic-induced hyperprolactinemia (hyperPRL). In the present study, we further examined the pharmacological action of PGD on prolactin (PRL) secretion using in vitro and in vivo models, with specific attention to the role of dopaminergic mediators and other sex hormones. Treatment with PGD at 1-5mg/ml significantly suppressed PRL secretion and synthesis in MMQ cells, a model of hyperPRL derived from pituitary adenoma cells. The suppressive effects were completely abolished by pretreatment with 10?M haloperidol, a dopamine D(2) receptor antagonist. Consistent with a D(2)-action, PGD did not affect PRL in rat pituitary lactotropic tumor-derived GH3 cells that lack the D(2) receptor expression but significantly increased the expression of D(2) receptors and dopamine transporters (DAT) in PC12 cells. In a rat model of hyperPRL, produced by repeated injection of the dopamine blocker metoclopramide (MCP), chronic PGD (2.5-10g/kg daily) significantly reduced elevated serum PRL. The reduction in magnitude was similar to that elicited by bromocriptine (BMT), a dopamine D(2) receptor agonist currently used for treatment of hyperPRL. Neither PGD nor BMT altered serum estradiol, but PGD reversed decreased serum progesterone to control level, whereas BMT did not. These results indicate that the anti-hyperPRL effects of PGD are associated not only with D(2) receptor and DAT modulation, but also with a normalization of other sex hormone dysfunction. This experimental evidence supports clinical use of PGD as an effective treatment of antipsychotic-induced hyperPRL. PMID:22796279

Wang, Di; Wong, Hei Kiu; Zhang, Li; McAlonan, Grainne M; Wang, Xiao-Min; Sze, Stephen Cho Wing; Feng, Yi-Bin; Zhang, Zhang-Jin

2012-12-01

9

Chemical taxonomy of tree peony species from China based on root cortex metabolic fingerprinting.  

PubMed

The section Moutan of the genus Paeonia consists of eight species that are confined to a small area in China. A wide range of metabolites, including monoterpenoid glucosides, flavonoids, tannins, stilbenes, triterpenoids, steroids, paeonols, and phenols, have been found in the species belonging to section Moutan. However, although previous studies have analyzed the metabolites found in these species, the metabolic similarities that can be used for the chemotaxonomic distinction of section Moutan species are not yet clear. In this study, HPLC-DAD-based metabolic fingerprinting was applied to the classification of eight species: Paeoniasuffruticosa, Paeoniaqiui, Paeoniaostii, Paeoniarockii, Paeoniajishanensis, Paeoniadecomposita, Paeoniadelavayi, and Paeonialudlowii. In total, of the 47 peaks that exhibited an occurrence frequency of 75% in all 23 tree peony samples, 43 of these metabolites were identified according to their retention times and UV absorption spectra, together with combined HPLC-QTOF-MS. These data were compared with reference standard compounds. The 43 isolated compounds included 17 monoterpenoid glucosides, 11 galloyl glucoses, 5 flavonoids, 6 paeonols and 4 phenols. Principal component analysis (PCA), and hierarchical cluster analysis (HCA), showed a clear separation between the species based on metabolomics similarities and four groups were identified. The results exhibited good agreement with the classical classification based on the morphological characteristics and geographical distributions of the subsections Vaginatae F.C. Stern and Delavayanae F.C. Stern with the exception of P. decomposita, which was found to be a transition species between these two subsections. According to their metabolic fingerprinting characteristics, P. ostii and P. suffruticosa can be considered one species, and this result is consistent with the viewpoint of medicinal plant scientists but different from that of classical morphological processing. Significantly large variations were obtained in the metabolic profiles of P. delavayi, whereas no significant difference was found between P. delavayi and P. ludlowii. This indicates that these two species have a close genetic relationship. In conclusion, the combination of HPLC-DAD and multivariate analyses has great potential for guiding future chemotaxonomic studies to examine the potential pharmaceutical value of the effective constituents of tree peony species and appears to be able to clarify the confusion and skepticism associated with the reported morphology- and molecular phylogenetics-based taxonomy of tree peonies. PMID:25220499

He, Chunnian; Peng, Bing; Dan, Yang; Peng, Yong; Xiao, Peigen

2014-11-01

10

Effects of shade on plant growth and flower quality in the herbaceous peony (Paeonia lactiflora Pall.).  

PubMed

Herbaceous peony (Paeonia lactiflora Pall.) is an important ornamental plant used in urban green spaces, but little is known about whether it can grow in a shaded environment or understory. In this study, effects of shade on plant growth and flower quality in the herbaceous peony were investigated. The results showed that P. lactiflora morphology parameters, including plant height, leaf number, stem diameter, branch number, node number and plant crown width, were higher in plants grown with sun exposure compared to those grown in shade; however, opposite trends were observed for the top and middle leaf areas of the plant. Compared with sun exposure, shade decreased P. lactiflora photosynthetic capacity, light saturation point (LSP) and light compensation point (LCP) and increased the apparent quantum yield (AQY), mainly due to declined stomatal conduction (Gs). These decreases caused the soluble sugar, soluble protein and malondialdehyde (MDA) contents to decline, which led to delayed initial flowering date, prolonged flowering time, reduced flower fresh weight, increased flower diameter and faded flower color. Through cloning and expression analysis of anthocyanin biosynthetic genes, we determined that the fading of flower color was the result of reduced anthocyanin content, which was caused by the combined activity of anthocyanin biosynthesis genes and, in particular, of the upstream phenylalanine ammonialyase gene (PlPAL) and chalcone synthase gene (PlCHS). These results could provide us with a theoretical basis for further application of P. lactiflora in the greening of urban spaces and an understanding of the mechanisms behind the changes induced by shade. PMID:23141672

Zhao, Daqiu; Hao, Zhaojun; Tao, Jun

2012-12-01

11

Iridoidal glycosides from Jasminum sambac  

Microsoft Academic Search

Besides a known trimeric iridoidal glycoside, sambacoside A, five new oligomeric iridoidal glycosides, molihuasides A-E were isolated from the flowers of Jasminum sambac. Their structures were determined by spectral and chemical evidence. Among them, molihuasides A and C-E are new dimeric iridoidal glycosides and molihuaside B is a new trimeric iridoidal glycoside.

Ying-Jun Zhang; Yu-Qing Liu; Xiang-Yu Pu; Chong-Ren Yang

1995-01-01

12

Microwave-Assisted Simultaneous Extraction of Luteolin and Apigenin from Tree Peony Pod and Evaluation of Its Antioxidant Activity  

PubMed Central

An efficient microwave-assisted extraction (MAE) technique was employed in simultaneous extraction of luteolin and apigenin from tree peony pod. The MAE procedure was optimized using response surface methodology (RSM) and compared with other conventional extraction techniques of macerate extraction (ME) and heat reflux extraction (HRE). The optimal conditions of MAE were as follows: employing 70% ethanol volume fraction as solvent, soaking time of 4?h, liquid-solid ratio of 10 (mL/g), microwave irradiation power of 265?W, microwave irradiation time of 9.6?min, and 3 extraction cycles. Under the optimal conditions, 151??g/g luteolin and 104??g/g apigenin were extracted from the tree peony pod. Compared with ME and HRE, MAE gave the highest extraction efficiency. The antioxidant activities of the extracts obtained by MAE, ME, and HRE were evaluated using a 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) free radical-scavenging assay, a ferric reducing antioxidant power assay (FRAP), and a reducing power assay. Meanwhile, the structural changes of the unprocessed and processed tree peony pod samples were analyzed by scanning electron microscopy.

Wang, Hongzheng; Yang, Lei; Zu, Yuangang; Zhao, Xiuhua

2014-01-01

13

Phenylethanoid and lignan glycosides from Verbascum thapsus.  

PubMed

Verbascum thapsus afforded, in addition to three known phenylethanoid glycosides and four lignan ones, five new phenylethanoid glycosides and one new lignan glycoside. Structures of the compounds were elucidated by spectroscopic methods and chemical evidence. PMID:1373629

Warashina, T; Miyase, T; Ueno, A

1992-03-01

14

Iridoid glycosides and glycosidic constituents from Eriophyton wallichii Benth.  

PubMed

C?-iridoid glycosides, wallichiisides A-C, and four dimers, wallichiisides D-G, together with 13 known glycosidic compounds, were isolated from whole plants of Eriophyton wallichii Benth. Their structures were elucidated by spectroscopic methods and comparison with literature values. Four of these compounds showed moderate DPPH free radical scavenging activity. PMID:21601897

Fan, Qiu-Ling; Tan, Chang-Heng; Liu, Jing; Zhao, Ming-Ming; Han, Fu-Sen; Zhu, Da-Yuan

2011-10-01

15

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

16

Phenylethanoid glycosides from Lippia javanica  

Microsoft Academic Search

Lippia javanica (N.L.Burm.) Spreng. is an aromatic, multipurpose medicinal plant from which a number of volatile compounds have been identified, together with toxic triterpenoids and iridoid glycosides. Two additional phenylethanoid glycosides, verbascoside and isoverbascoside, were isolated from L. javanica and characterized. High performance liquid chromatography analyses of polar extracts of three other Lippia species (L. scaberrima, L. rehmannii and L.

D. K. Olivier; E. A. Shikanga; S. Combrinck; R. W. M. Krause; T. Regnier; T. P. Dlamini

2010-01-01

17

Triterpene glycosides from Saponaria officinalis  

Microsoft Academic Search

Conclusions  The roots ofSaponaria officinalis L. have yielded the known triterpene glycoside gypsoside and the first glycoside of gypsogenic acid, which has been named\\u000a saponaroside. Saponaroside is the 3-?-D-xylopyranoside of gypsogenic acid.

V. G. Bukharov; S. P. Shcherbak

1969-01-01

18

Synthesis and photochromic properties of configurationally varied azobenzene glycosides.  

PubMed

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. PMID:25050228

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

2014-06-01

19

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. PMID:25050228

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

2014-01-01

20

Pain?relieving effect of a compound isolated from white peony root oral liquid on acute radiation?induced esophagitis.  

PubMed

Acute radiation?induced esophagitis (ARIE) is a common complication of radiotherapy. The aim of this study was to clarify the molecular mechanism of pain relief by the compound of white peony root oral liquid (cWPROL) in ARIE. An animal model of ARIE was established and either cWPROL or a mixture of lidocaine, dexamethasone and gentamycin (mLDG) was administered. We indirectly observed rat symptoms of pain by recording the weight of food and the volume of water consumed by the rats, along with changes in body weight. Additionally, the expression levels of substance P (SP) in the esophageal tissues were detected by immunohistochemistry. It was demonstrated that cWPROL was able to release the pain of ARIE by decreasing the expression of SP; this may be one of the molecular mechanisms via which cWPROL induces pain relief. PMID:23588387

Wang, Zhiyu; Shen, Li; Li, Xing; Shu, Xin; Shan, Baoen; Zhang, Li; Gong, Yanjun; Dong, Zhiming

2013-06-01

21

Ecdysteroid glycosides: identification, chromatographic properties, and biological significance.  

PubMed

Ecdysteroid glycosides are found in both animals and plants. The chromatographic behavior of these molecules is characteristic, as they appear much more polar than their corresponding free aglycones when analyzed by normal-phase high-performance liquid chromatography (HPLC), whereas the presence of glycosidic moieties has a very limited (if any) impact on polarity when using reversed-phase HPLC. Biological activity is greatly reduced because the presence of this bulky substituent probably impairs the interaction with ecdysteroid receptor(s). 2-Deoxy-20-hydroxyecdysone 22-O-beta-D-glucopyranoside, which has been isolated from the dried aerial parts of Silene nutans (Caryophyllaceae), is used as a model compound to describe the rationale of ecdysteroid glycoside purification and identification. PMID:15842754

Maria, Annick; Girault, Jean-Pierre; Saatov, Ziyadilla; Harmatha, Juraj; Dinan, Laurence; Lafont, René

2005-03-01

22

Acylated flavone glycosides from Veronica  

Microsoft Academic Search

A survey of the flavonoid glycosides of selected taxa in the genus Veronica yielded two new acylated 5,6,7,3?,4?-pentahydroxyflavone (6-hydroxyluteolin) glycosides and two unusual allose-containing acylated 5,7,8,4?-tetrahydroxyflavone (isoscutellarein) glycosides. The new compounds were isolated from V. liwanensis and V. longifolia and identified using NMR spectroscopy as 6-hydroxyluteolin 4?-methyl ether 7-O-?-rhamnopyranosyl(1??2?)[6?-O-acetyl-?-glucopyranoside] and 6-hydroxyluteolin 7-O-(6?-O-(E)-caffeoyl)-?-glucopyranoside, respectively. Isoscutellarein 7-O-(6?-O-acetyl)-?-allopyranosyl(1??2?)-?-glucopyranoside was obtained from both V.

Dirk C. Albach; Renée J. Grayer; Søren Rosendal Jensen; Fevzi Özgökce; Nigel C. Veitch

2003-01-01

23

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

24

Acylated flavone glycosides from Veronica.  

PubMed

A survey of the flavonoid glycosides of selected taxa in the genus Veronica yielded two new acylated 5,6,7,3',4'-pentahydroxyflavone (6-hydroxyluteolin) glycosides and two unusual allose-containing acylated 5,7,8,4'-tetrahydroxyflavone (isoscutellarein) glycosides. The new compounds were isolated from V. liwanensis and V. longifolia and identified using NMR spectroscopy as 6-hydroxyluteolin 4'-methyl ether 7-O-alpha-rhamnopyranosyl(1"'-->2")[6"-O-acetyl-beta-glucopyranoside] and 6-hydroxyluteolin 7-O-(6"-O-(E)-caffeoyl)-beta-glucopyranoside, respectively. Isoscutellarein 7-O-(6"'-O-acetyl)-beta-allopyranosyl(1"'-->2")-beta-glucopyranoside was obtained from both V. intercedens and V. orientalis and its 4'-methyl ether from V. orientalis only. Complete 1H and 13C NMR spectral assignments are presented for both isoscutellarein glycosides. Two iridoid glucosides new to the genus Veronica (melittoside and globularifolin) were also isolated from V. intercedens. PMID:14599528

Albach, Dirk C; Grayer, Renée J; Jensen, Søren Rosendal; Ozgökce, Fevzi; Veitch, Nigel C

2003-12-01

25

High throughput chemiluminescence platform for evaluating antioxidative activity of total flavonoid glycosides from plant extracts  

Microsoft Academic Search

A high throughput chemiluminescence (CL) platform for rapidly evaluating antioxidant activity of total flavonoid glycosides from plant extracts was developed originally based on their inhibition effects on the CL reaction of 1,1-dipheny-2-picrylhydrazyl (DPPH)–luminol or H2O2–luminol system. With the method, total flavonoid glycosides extracts were screened through detecting the inhibited CL intensity, which was reversely correlative to antioxidant activity of the

Hong Yao; Bin Wu; Yiyu Cheng; Haibin Qu

2009-01-01

26

Monoterpene glycosides, phenylpropanoids, and acacetin glycosides from Dracocephalum foetidum.  

PubMed

Chemical investigation of the acetone extract from the aerial parts of the Mongolian medicinal plant Dracocephalum foetidum resulted in the isolation of three limonene glycosides, a caffeic acid trimer, four rosmarinic acid glucosides, and five acacetin acyl glycosides, together with 13 known natural products. The chemical structures of all of the compounds were determined by spectroscopic analyses. Among these compounds three showed hyaluronidase inhibitory activity. In addition, one other compound showed stronger 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity than the positive control Trolox, whereas three other compounds demonstrated a similar activity to that of Trolox. PMID:24582463

Selenge, Erdenechimeg; Murata, Toshihiro; Tanaka, Shiho; Sasaki, Kenroh; Batkhuu, Javzan; Yoshizaki, Fumihiko

2014-05-01

27

Sesquiterpene Glycosides from Calendula persica.  

PubMed

The polar fractions of the extract of the aerial parts of CALENDULA PERSICA afforded eight sesquiterpene glycosides, five derived from viridiflorol, two of beta-eudesmol, and one of 4alpha-hydroxygermacra-1(10) E,5E-diene. In addition to fucopyranosides, also chinovopyranosides were present. The structures were elucidated by high field NMR techniques. PMID:17265265

Jakupovic, J; Grenz, M; Bohlmann, F; Rustaiyan, A; Koussari, S

1988-06-01

28

Iridoid glycosides of Cornus canadensis  

Microsoft Academic Search

The iridoid glycosides scandoside, scandoside methyl ester, monotropein, and galioside were found in Cornus canadensis from several widely distributed collection sites. Cornin and hastatoside were isolated from C. nuttallii. No iridoids were found in C. stolonifera, that instead yielded cornoside and halleridone, also independent of collection location. The results were compared with previous studies and current phylogenetic work on the

Frank R Stermitz; Robert E Krull

1998-01-01

29

[Interspecific hybridization in the genus Paeonia (Paeoniaceae): polymorphic sites in transcribed spacers of the 45S rRNA genes as indicators of natural and artificial peony hybrids].  

PubMed

The ITS1-5.8S rDNA-ITS2 regions of 33 accessions belonging to 16 species and five natural and garden interspecific hybrids of the genus Paeonia L. were sequenced. Chromatograms of the peony hybrids demonstrated the presence of the signals, corresponding to two different nucleotides at the positions differing in the parents, indicating that in the hybrids, no rDNA isogenization usually occurred, and they preserved rDNA of both parents. Analysis of these polymorphic sites (PS) showed that P. x majkoae was interspecific hybrid between P. tenuifolia and P. caucasica. The ITS of P. hybrida differs from ITS of P. x majkoae in 19 mutations. Because of this, P. x majkoae is definitely not synonymous to P. hybrida. Comparative analysis of ITS 1-5.8S rDNA-ITS2 showed that species diversity in section Paeonia was based on recombination as a result of intraspecific hybridization of three haplotype families. Specifically, haplotypes A, typical of the P. tenuifolia and P. anomala genomes, haplotypes B, typical of P. mlokosewitschii and P. obovata, and haplotypes of family C, currently represented in rDNA of diploid and tetraploid forms of some Caucasian and Mediterranean species. The ITS regions many diploid peonies contain no dimorphic sites, while P. oreogeton, P. cambessedesii, P. rhodia, and P. daurica carry from ten to 17 PS, and supposed to be the interspecific hybrids. Most of the tetraploid peonies contain from six to 18 PS in the ITS regions. These are alloploids with one of the parental genomes similar to that of P. mlokosewitschii (B1), or P. obovata (B3). The second parental genome in P. banatica, P. peregrina, and P. russii is represented by the genome, close to that of P. tenuifolia (A). P. macrophylla, P. mascula, P. coriacea, P. wittmanniana, and P. tomentosa carry genome of series B and genome of series C, which slightly resembles genome A. PMID:22988767

Punina, E O; Machs, E M; Krapivskaia, E E; Kim, E S; Mordak, E V; Miakoshina, Iu A; Rodionov, A V

2012-07-01

30

Diterpene glycosides from Stevia rebaudiana.  

PubMed

Three novel diterpene glycosides were isolated for the first time from the commercial extract of the leaves of Stevia rebaudiana, along with several known steviol glycosides, namely stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compounds were identified as 13-[(2-O-?-D-glucopyranosyl-3-O-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy] ent-kaur-15-en-19-oic acid, 13-[(2-O-?-D-glucopyranosyl-3-O-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy]-16?-hydroxy-ent-kauran-19-oic acid and 13-methyl-16-oxo-17-nor-ent-kauran-19-oic acid-?-D-glucopyranosyl ester on the basis of extensive 2D NMR and MS spectroscopic data as well as chemical studies. PMID:21527882

Chaturvedula, Venkata Sai Prakash; Upreti, Mani; Prakash, Indra

2011-01-01

31

Flavonol glycosides from Dryas octopetala.  

PubMed

Six flavonol glycosides and ent-epicatechin were isolated from Dryas octopetala and their structures elucidated by chemical and spectroscopic methods. Two new flavonoids, 3-O-alpha-L-arabinofuranosyl-8-methoxyquercetin (2) and 3-O-beta-galactopyranosyl-8-methoxykaempferol (6), were identified along with 3-O-beta-D-galactopyranosylquercetin (hyperin) (3), 3-O-alpha-L-arabinofuranosylquercetin (avicularin) (5), 3-O-beta-L-arabinopyranosylquercetin (4), and 3-O-beta-D-galactopyranosyl-8-methoxyquercetin (1). PMID:6512533

Servettaz, O; Colombo, M L; De Bernardi, M; Uberti, E; Vidari, G; Vita-Finzi, P

1984-01-01

32

Dihydroflavonol glycosides from rhododendron ferrugineum  

Microsoft Academic Search

Chemical investigation of the leaves and the flowers of Rhododendron ferrugineum afforded six known flavonoids: hyperoside, myricetin 3-O-?-galactopyranoside, kaempferol 3-O-(6?-O-acetyl)-glucoside, quercetin 3-O-(6?-O-acetyl)-glucoside, quercetin 3-O-(6?-O-acetyl)-galactoside, quercetin 3-O-(3?,6?-O-diacetyl)-galactoside and two new dihydroflavonol glycosides: trans-taxifolin 3-O-?-arabinopyranoside and cis-taxifolin 3-O-?-arabinopyranoside.

E Chosson; A Chaboud; A. J Chulia; J Raynaud

1998-01-01

33

Myricetin glycosides from Licania densiflora  

Microsoft Academic Search

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.

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

2001-01-01

34

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

35

UDP-dependent glycosyltransferases involved in the biosynthesis of steviol glycosides.  

PubMed

A short-term experiment was designed to measure the transcript levels of downstream genes contributing to the biosynthesis of steviol glycosides. Stevia rebaudiana plants were subjected to long- and short-day conditions for different time intervals. Samples from both lower and upper leaves were collected. Using quantitative real-time polymerase chain reaction, the transcript levels of three UDP-dependent glycosyltransferases, UGT85C2, UGT74G1 and UGT76G1, were studied. The results were compared with the steviol glycoside contents measured in the leaves, which were quantified by reversed phase HPLC. In the same daylength condition, steviol glycoside concentration and the transcript levels of the three UGT genes were higher in upper leaves than in lower leaves. Steviol glycosides accumulated more in plants under short-day conditions. Under these conditions, a highly significant correlation was found between UGT85C2 transcription and total steviol glycoside accumulation in the upper leaves. This suggests that the glycosylation of steviol to form steviolmonoside is the rate-limiting step in the glycosylation pathway of steviol glycosides. In these upper leaves, a relatively high accumulation of rebaudioside A compared to stevioside was also observed, however, without correlation with the transcription of UGT76G1. PMID:21477883

Mohamed, Amal A A; Ceunen, Stijn; Geuns, Jan M C; Van den Ende, Wim; De Ley, Marc

2011-07-01

36

A dammarane glycoside derived from ginsenoside Rb3.  

PubMed

A dammarane glycoside, designated compound Mx (C-Mx), was isolated from the hydrolysate of 20(S)-protopanaxadiol type ginsenosides containing G-Rb(3) from Panax notoginseng leaves with crude snailase. Its chemical structure was elucidated to be 20-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl-20(S)-protopanaxadiol on the basis of spectral analysis. Its cytotoxicity against breast cancer cell line MCF-7 and effects on the sensitivity to doxocubicin of doxocubicin-resistant MCF-7 cells were also investigated. The new compound showed moderate cytotoxicity and partial reversal of doxocubicin resistance. PMID:15684516

He, Kejiang; Liu, Yong; Yang, Yi; Li, Peng; Yang, Ling

2005-02-01

37

Glycoside hydrolases of rumen bacteria and protozoa  

Microsoft Academic Search

Sixteen strains of rumen bacteria and 21 protozoal preparations were screened for glycoside hydrolase and phosphatase activity, using 22 nitrophenyl glycoside substrates. The range and level of bacterial enzyme activities were species dependent, although, the glycosidases associated with plant cell wall breakdown were most active in the cellulolytic and hemicellulolytic species. Alkaline phosphatase occurred widely in the organisms examined, but

Alan G. Williams; Susan E. Withers; Geoffrey S. Coleman

1984-01-01

38

Benzyl benzoate glycosides from Oligoneuron rigidum.  

PubMed

Two new benzyl benzoate glycosides were isolated from the leaves and stems of the native North American prairie plant Oligoneuron rigidum (stiff goldenrod). The glycosides were isolated as a mixture of benzoate and acetate esters, which were subjected to mild base hydrolysis to facilitate full structural characterization using LCMSMS and 1D and 2D NMR data. PMID:23121124

Miesner, Sarah; Frosch, Holly; Kindscher, Kelly; Tichy, Shane; Manfredi, Kirk P

2012-11-26

39

Bioavailability of genistein and its glycoside genistin  

Microsoft Academic Search

Genistein belongs to the class of isoflavones. The main sources of isofiavones in food are soybeans and soy-based products. Most isoflavones in plants are bound to sugars such as the glycosides genistin and daidzin. Understanding the various factors that influence absorption and metabolism of isoflavones and especially of their naturally occurring glycosides, is essential to fully elucidate and understand the

Aukje Steensma

2006-01-01

40

Alleviating coking in ethanol steam reforming by co-loading binary oxides Ni-M (M=Ag, Cu, Mn) on peony-like ceria  

NASA Astrophysics Data System (ADS)

Previously, hydrothermally prepared mesoporous peony-like ceria (PCO) material was shown to exhibit superior catalytic properties for CO oxidation and ethanol reforming. Ni supported PCO had been shown to have high activity for ethanol steam reforming at low temperature. In this work, Ag, Cu and Mn is co-loaded with Ni on PCO catalysts by impregnation method. The catalysts were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and a combined thermogravimetry, differential scanning calorimetry, and mass spectrometry (TG-DSC-MS). It was found that all the catalysts gave 100% ethanol conversion above ca. 300°C and exhibited similar H2 yield. It is found that the severe coking problem for the Ni-loaded PCO catalyst was alleviated significantly if Ag, Cu or Mn is co-loaded. Among them, the addition of Mn is the most effective in reducing carbon formation.

Xian, C. N.; Li, J. G.; Li, H.; Chen, L. Q.; Sun, J.; Lee, J. S.

2011-06-01

41

Pregnane glycosides from Leptadenia pyrotechnica.  

PubMed

The whole plant of Leptadenia pyrotechnica afforded 18 new pregnane glycosides (1-18) with sarcostin, 11-hydroxysarcostin, and deacetylmetaplexigenin as the aglycon moieties and acetyl, benzoyl, cinnamoyl, p-coumaroyl, and nicotinoyl ester moieties linked at C-12 and/or C-20 of the aglycon and hexopyranose, 6-deoxy-3-O-methylhexopyranose, and 2,6-dideoxy-3-O-methylhexopyranose sugars linked at C-3 of their aglycon. The structures of these compounds were elucidated by spectroscopic data interpretation and from chemical evidence. The antiproliferative activity of all compounds was evaluated using three continuous murine and human culture cell lines, J774.A1, HEK-293, and WEHI-164. Compounds having deacethylmetaplexigenin as aglycon and a cinnamoyl ester moiety linked at C-12 were the most active constituents. PMID:16643040

Cioffi, Giuseppina; Sanogo, Rokia; Vassallo, Antonio; Dal Piaz, Fabrizio; Autore, Giuseppina; Marzocco, Stefania; De Tommasi, Nunziatina

2006-04-01

42

Two new glycosides from Conyza bonariensis.  

PubMed

Studies on Conyza bonariensis (L.) Cronq. led to the isolation of two new glycosides trivially named as erigeside E and F (1-2), along with two new source compounds; benzyl-beta-D-glucopyranoside (3) and 2-phenylethyl-beta-D-glucopyranoside (4). Compounds 1, 3, and 4 are aromatic glycosides, while compound 2 is an alkyl glycoside. Their structures were elucidated through mass spectrometric, and 1D- and 2D-NMR spectroscopic techniques, including 1H NMR, 13C NMR, HMQC, HSQC and HMBC. PMID:20734949

Zahoor, Aqib; Siddiqui, Imran Nafees; Khan, Afsar; Ahmad, Viqar Uddin; Ahmed, Amir; Hassan, Zahid; Khan, Saleha Suleman; Iqbal, Shazia

2010-07-01

43

Kaempferol glycosides and cardenolide glycosides, cytotoxic constituents from the seeds of Draba nemorosa (Brassicaceae)  

Microsoft Academic Search

Bioassay-directed fractionation of a methanolic extract from the seeds of Draba nemorosa (Brassicaceae) led to isolation of a new flavonol glycoside, drabanemoroside (5, kaempferol 3-O-?-L-rhamnopyranosyl-(1?2)-?-L-arabinopyranose) along with four known flavonoid derivatives (1–4), four cardenolide glycosides (6–9). Kaempferol glycosides 2 and 5 showed strong cytotoxicity against human small lung cancer cell line A549 and melanoma SK-Mel-2 with an IC50 of 0.5

Surk-Sik Moon; Aziz Abdur Rahman; Maniruzzaman Manir; V. S. Jamal Ahamed

2010-01-01

44

Triterpene glycosides from the far eastern sea cucumber Pentamera calcigera II: disulfated glycosides.  

PubMed

Three new triterpene glycosides, calcigerosides D(1) (1), D(2) (2), and E (3), have been isolated from the sea cucumber Pentamera calcigera. Their structures have been deduced from extensive spectral analysis (NMR and MS) and chemical evidence. All the compounds are disulfated pentaosides differing in aglycon structure and position of sulfate group, which were determined by the measurement of NT(1) values in the cases of glycosides 1 and 2. Glycoside 1 is a nonholostane derivative, that is, it lacks an 18(20)-lactone, which is very rare among the sea cucumber glycosides. PMID:11076550

Avilov, S A; Antonov, A S; Drozdova, O A; Kalinin, V I; Kalinovsky, A I; Riguera, R; Lenis, L A; Jiménez, C

2000-10-01

45

Immunomodulatory sesquiterpene glycosides from Dendrobium nobile  

Microsoft Academic Search

Four sesquiterpene glycosides with alloaromadendrane, emmotin, and picrotoxane type aglycones were isolated from the stems of Dendrobium nobile Lindl (Orchidaceae). Their structures were determined by spectroscopic methods and chemical reactions. Immunomodulatory activity of the isolates was evaluated in vitro.

Qinghua Ye; Guowei Qin; Weimin Zhao

2002-01-01

46

A flavonol glycoside from Embelia schimperi leaves  

Microsoft Academic Search

A new flavonol glycoside, quercetin 3-galactosyl (1 ? 2) rhamnoside, has been isolated from the leaves of Embelia schimperi. The known compounds quercetin 3-rutinoside, quercetin 3-rhamnoside, quercetin 3-galactoside, myricetin and quercetin were also identified from this plant.

Lawrence O. Manguro Arot; Lawrence A. D. Williams

1997-01-01

47

A caffeoyl phenylethanoid glycoside from plantago myosuros  

Microsoft Academic Search

From Plantago myosuros, the iridoid glucoside, aucubin was isolated, together with the caffeoyl phenylethanoid glycosides, plantalloside and verbascoside. Plantalloside is a new verbascoside analogue with a ?-allopyranosyl moiety. The structure was elucidated by NMR spectroscopy.

Henrik Franzyk; Tommy Lykke Husum; Søren Rosendal Jensen

1998-01-01

48

A new diterpene glycoside from Stevia rebaudiana.  

PubMed

From the commercial extract of the leaves of Stevia rebaudiana, a new diterpene glycoside was isolated besides the known steviol glycosides including stevioside, rebaudiosides A-F, rubusoside and dulcoside A. The new compound was identified as 13-[(2-O-?-D-glucopyranosyl-3-O-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-(2-O-?-L-rhamnopyranosyl-?-D-glucopyranosyl) ester (1) on the basis of extensive spectroscopic (NMR and MS) and chemical studies. PMID:21464800

Chaturvedula, Venkata Sai Prakash; Prakash, Indra

2011-01-01

49

Iridoid and megastigmane glycosides from Phlomis aurea  

Microsoft Academic Search

From the leaves of Phlomis aurea, two new iridoids of unique structures named 3-epiphlomurin (1) and phlomurin (2), a new megastigmane glucoside phlomuroside (3) and a new benzyl alcohol glycoside having the structure benzyl alcohol-O-?-xylopyranosyl-(1?2)-?-glucopyranoside (4) have been isolated together with four known iridoids auroside, lamiide, 8-epiloganin and ipolamiide, two known phenolic glycosides acteoside (verbascoside) and syringin, one known phenylethanoid

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

2000-01-01

50

Triterpene glycosides of Dianthus deltoides. I  

Microsoft Academic Search

Summary FromDianthus deltoides L. we have isolated three new triterpene glycosides: dianthosides A, B, and C. It has been shown that dianthoside A is the 3-O-ß-glucopyranoside and dianthoside B the 3-O-[O-ß-D-glucopyranosyl-(1 ? 6)-ß-glucopyranoside] of gypsogenic acid. Some information on the structure of dianthoside C — a new glycoside of gypsogenin — has been obtained.

V. G. Bukharov; S. P. Shcherbak; A. P. Beshchekova

1971-01-01

51

Triterpenoid glycosides from Anagallis arvensis.  

PubMed

From the herb of Anagallis arvensis, we have isolated four novel oleanane glycosides, anagallosaponins VI-IX, and two artifact saponins, apoanagallosaponins III and IV, formed from anagallosaponins III and IV. The structures were elucidated by chemical and spectral methods, 2D NMR techniques being particularly helpful. The structures of anagallosaponins VI and VII were characterized as priverogenin B 3-O-beta-D-xylopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->4)-alpha-L-arabinopyranoside and 3-O-(beta-D-glucopyranosyl (1-->4)-[beta-D-xylopyranosyl (1-->2)]beta-D-glucopyranosyl (1-->4)-alpha-L-arabinopyranoside), respectively. The structures of anagallosaponins VIII and IX were characterized as 23-hydroxypriverogenin B 22-acetate 3-O-(beta-D-xylopyranosyl (1-->2)-O-beta-D-glucopyranosyl (1-->4)[beta-D-glucopyranosyl (1-->2)]-alpha-L-arabinopyranoside), 3-O-(beta-D-glucopyranosyl (1-->4)-[beta-D-xylopyranosyl (1-->2)]beta-D-glucopyranosyl (1-->4)[beta-D-glucopyranosyl (1-->2)]- alpha-L-arabinopyranoside), respectively. The structures of apoanagallosaponins III and IV were characterized as camelliagenin A 16-acetate 3-O-beta-D-xylopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->4)-alpha-L-arabnopyranoside, 3-O-(beta-D-xylopyranosyl (1-->2)-O-beta-D-glucopyranosyl (1-->4)[beta-D-glucopyranosyl (1-->2)]-alpha-L-arabinopyranoside), respectively. PMID:7765757

Shoji, N; Umeyama, A; Yoshikawa, K; Arihara, S

1994-11-01

52

FLAVONE C-GLYCOSIDES AND CUCURBITACIN GLYCOSIDES FROM CITRULLUS COLOCYNTHIS  

Microsoft Academic Search

Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) is an Iranian medicinal plant that has traditionally been used as an abortifacient and to treat constipation, oedema, bacterial infections, cancer and diabetes. As part of our on-going studies on Iranian medicinal plants, thorough phytochemical investigation was carried out on this plant. The reversed-phase preparative HPLC was employed to isolate compounds from the butanol fraction

SIMON GIBBONS; ALI REZA KOSARI; MASOUD MODARRESI; SATYAJIT D. SARKER

2006-01-01

53

Isolation, Structure Elucidation, and Biological Activity of Flavone 6-C-Glycosides from Alliaria petiolata  

Microsoft Academic Search

Preparative reversed-phase HPLC analysis of a methanol extract of the seeds of Alliaria petiolata afforded fourflavone 6-C-glycosides: isoorientin, swertiajaponin, swertisin and isoscoparin-2?-ß-D-glucopyranoside. The molecular structures were elucidated by UV, ESIMS and comprehensive 1D (1H and 13 C) and 2D (gradient multiple quantum filtered 1H-1H COSY, 1H-13C HSQC and 1H-13C HMBC) NMR analyses. The antibacterial and free radical scavenging activity, and

Y. Kumarasamy; M. Byres; P. J. Cox; A. Delazar; M. Jaspars; L. Nahar; M. Shoeb; S. D. Sarker

2004-01-01

54

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

55

Glycoside of hypsogenic acid from Saponaria officinalis L  

Microsoft Academic Search

A glycoside of hypsogenic acid called saponaroside has been isolated for the first time from the roots ofSaponaria officinalis L. It was shown that the glycoside isß-D-xylopyranoside-3-hypsogenic acid.

V. G. Bukharov; S. P. Shcherbak

1969-01-01

56

Phenylethanoid and iridoid glycosides from Veronica persica.  

PubMed

A new phenylethanoid glycoside, persicoside (1) and three known phenylethanoid glycosides, acteoside (2), isoacteoside (3) and lavandulifolioside (4) were isolated from the aerial parts of Veronica persica. On the basis of spectral analyses, the structure of the new compound was elucidated to be 3,4-dihydroxy-beta-phenylethoxy-O-[beta-D-glucopyranosyl-(1-->2)]-[beta-D-glucopyranosyl-(1-->3)]-4-O-caffeoyl-beta-D-glucopyranoside. Persicoside (1) and acteoside (2) exhibited radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Beside phenylethanoid glycosides, a hexitol, dulcitol (5) and seven known iridoid glucosides, aucubin (6), veronicoside (7), amphicoside (8), 6-O-veratroyl-catalpol (9), catalposide (10), verproside (11) and verminoside (12) were isolated. PMID:12045353

Harput, U Sebnem; Saracoglu, Iclal; Inoue, Makoto; Ogihara, Yukio

2002-06-01

57

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

58

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

59

Sesquiterpene lactone glycosides from Arnica longifolia.  

PubMed

Flowers of ARNICA LONGIFOLIA were investigated for the occurrence of sesquiterpene lactone glycosides. A mixture containing the two isomeric 11alpha,13-dihydro- and 11beta,13-dihydro-4 H-tomentosin glucosides, previously isolated from A. AMPLEXICAULIS and A. MOLLIS, together with the two isomeric 11alpha,13-dihydro- and 11beta,13-dihydro-4 H-carabrone glucosides were found in A. LONGIFOLIA. All carbon and proton shifts of the glycosides could be assigned by their 2D-COSY and 2D-HETCOR spectra and spectroscopy of their respective aglycones, obtained via enzymatic hydrolysis. PMID:17260246

Passreiter, C M; De Carlo, M; Steigel, A

1999-03-01

60

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

61

Neolignan and flavonoid glycosides in Juniperus communis var. depressa  

Microsoft Academic Search

Two neolignan glycosides (junipercomnosides A and B) were isolated from aerial parts of Juniperus communis var. depressa along with two known neolignan glycosides and seven flavonoid glycosides. The structures of the isolated compounds were determined by spectral analysis, in particular by 2D-NMR analysis. The significance of distribution of flavonoids in the chemotaxonomy of genus Juniperus was also discussed.

Tsutomu Nakanishi; Naoki Iida; Yuka Inatomi; Hiroko Murata; Akira Inada; Jin Murata; Frank A. Lang; Munekazu Iinuma; Toshiyuki Tanaka

2004-01-01

62

Neolignan and flavonoid glycosides in Juniperus communis var. depressa.  

PubMed

Two neolignan glycosides (junipercomnosides A and B) were isolated from aerial parts of Juniperus communis var. depressa along with two known neolignan glycosides and seven flavonoid glycosides. The structures of the isolated compounds were determined by spectral analysis, in particular by 2D-NMR analysis. The significance of distribution of flavonoids in the chemotaxonomy of genus Juniperus was also discussed. PMID:14732280

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

2004-01-01

63

Kaempferol glycosides and cardenolide glycosides, cytotoxic constituents from the seeds of Draba nemorosa (Brassicaceae).  

PubMed

Bioassay-directed fractionation of a methanolic extract from the seeds of Draba nemorosa (Brassicaceae) led to isolation of a new flavonol glycoside, drabanemoroside (5, kaempferol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranose) along with four known flavonoid derivatives (1-4), four cardenolide glycosides (6-9). Kaempferol glycosides 2 and 5 showed strong cytotoxicity against human small lung cancer cell line A549 and melanoma SK-Mel-2 with an IC(50) of 0.5 microg/mL and 1.9 microg/mL, respectively. Cardenolide glycosides 6-9 showed potent cytotoxicity (A549) in the range of 0.01-0.032 microg/mL. Their structures were characterized based on spectroscopic data (2D NMR, HRTOFMS, IR, and UV) and comparison of literature values. The carbohydrate units were also confirmed by comparing the hydrolysate of 5 with authentic monosaccharides. PMID:20803119

Moon, Surk-Sik; Rahman, Md Aziz Abdur; Manir, Md Maniruzzaman; Jamal Ahamed, V S

2010-08-01

64

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

65

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

66

Two new secoiridoid glycosides from Gentiana algida.  

PubMed

Two new acylated secoiridoid glycosides were isolated from the aqueous acetone extract of the whole herb of Gentiana algida. The structures of these new products were established by spectral and chemical methods as 6'-(2,3-dihydroxybenzoyl)sweroside and 6'-(2,3-dihydroxybenzoyl)swertiamarin, respectively. PMID:17252380

Tan, R X; Hu, J; Dong, L D; Wolfender, J L; Hostettmann, K

1997-12-01

67

A flavonol glycoside from Myrsine africana leaves  

Microsoft Academic Search

Myricetin 3-(3?,4?-diacetylrhamnoside), a novel flavonol glycoside together with myricetin 3-rhamnoside, myricetin 7-rhamnoside, myricetin 3-xyloside, myricetin 3-arabinoside, quercetin 3-galactoside, 3?-O-methylquercetin 3-glucoside, myricetin, quercetin, kaempferol and gallic acid have been isolated from a methanolic extract of Myrsine africana leaves.

Lawrence O. Manguro Arot; Jacob Ogweno Midiwo; Wolfgang Kraus

1996-01-01

68

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

69

Efficiency of transcellular transport and efflux of flavonoids with different glycosidic units from flavonoids of Litsea coreana L. in a MDCK epithelial cell monolayer model.  

PubMed

Although there is strong evidence to suggest that beneficial effects of the flavonoids in human health, the extent to which flavonoids are absorbed and the mechanisms involved are controversial. The objective of this study was to determine the bi-directional permeability and efflux characters of the four main flavonoids with different glycosidic units isolated from flavonoids of Litsea coreana L. and to discuss the transport mechanisms using the epithelial cell model MDCK. The transport of the four main flavonoid glycosides at concentration of 40, 80, 160 ?M was concentration-dependent in both apical to basolateral and the reverse direction. Contemporary, the influx and efflux of the flavonoid glycosides were temperature-dependent and pH-dependent at concentration of 80 ?M, and transport of flavonoid glycosides was obviously decreased when experiments performed in the presence of 1mM sodium azide (an ATP inhibitor). Uptake of quercetin-3-O-?-D-glucoside or kaempferol-3-O-?-D-glucoside was inhibited by 50 ?M phloridzin, a specific and competitive inhibitor of SGLT. Moreover, the flavonoids exhibited significantly larger basolateral to apical Papp than that of the reverse direction, suggesting the existence of efflux mechanisms. The 50 ?M verapamil, a chemical inhibitor of P-glycoprotein (P-gp), had no effect on the transport of four flavonoid glycosides. However, 50 ?M MK-571 or 1 mM probenecid, MRP2 inhibitors, led to an apparently decrease in the efflux of flavonoid glycosides. Therefore, MRP2 but P-gp may be involved in the transport of the four flavonoid glycosides. Taken together, the experimental observations in our study provide useful information for pharmacological applications of flavonoids with different glycosidic units from flavonoids of L. coreana L. PMID:24365259

Chen, Zhaolin; Ma, Taotao; Huang, Cheng; Zhang, Lei; Zhong, Jian; Han, Jingwen; Hu, Tingting; Li, Jun

2014-03-12

70

Genetic Structure of the Tree Peony (Paeonia rockii) and the Qinling Mountains as a Geographic Barrier Driving the Fragmentation of a Large Population  

PubMed Central

Background Tree peonies are great ornamental plants associated with a rich ethnobotanical history in Chinese culture and have recently been used as an evolutionary model. The Qinling Mountains represent a significant geographic barrier in Asia, dividing mainland China into northern (temperate) and southern (semi–tropical) regions; however, their flora has not been well analyzed. In this study, the genetic differentiation and genetic structure of Paeonia rockii and the role of the Qinling Mountains as a barrier that has driven intraspecific fragmentation were evaluated using 14 microsatellite markers. Methodology/Principal Findings Twenty wild populations were sampled from the distributional range of P. rockii. Significant population differentiation was suggested (FST value of 0.302). Moderate genetic diversity at the population level (HS of 0.516) and high population diversity at the species level (HT of 0.749) were detected. Significant excess homozygosity (FIS of 0.076) and recent population bottlenecks were detected in three populations. Bayesian clusters, population genetic trees and principal coordinate analysis all classified the P. rockii populations into three genetic groups and one admixed Wenxian population. An isolation-by-distance model for P. rockii was suggested by Mantel tests (r?=?0.6074, P<0.001) and supported by AMOVA (P<0.001), revealing a significant molecular variance among the groups (11.32%) and their populations (21.22%). These data support the five geographic boundaries surrounding the Qinling Mountains and adjacent areas that were detected with Monmonier's maximum-difference algorithm. Conclusions/Significance Our data suggest that the current genetic structure of P. rockii has resulted from the fragmentation of a formerly continuously distributed large population following the restriction of gene flow between populations of this species by the Qinling Mountains. This study provides a fundamental genetic profile for the conservation and responsible exploitation of the extant germplasm of this species and for improving the genetic basis for breeding its cultivars. PMID:22523566

Yuan, Jun-hui; Cheng, Fang-Yun; Zhou, Shi-Liang

2012-01-01

71

Sesquiterpenoid glycosides from glandular trichomes of the wild tomato relative Solanum habrochaites.  

PubMed

Profiles of terpenoid glycoside metabolites in glandular trichomes of Solanum habrochaites LA1777 leaves were generated using ultrahigh performance liquid chromatography/time-of-flight mass spectrometry with multiplexing of non-selective collision-induced dissociation (CID). Profiling data suggested a diverse group of 52 sesquiterpenoid glycosides, and fragment ions observed in both non-selective CID mass spectra and true tandem mass spectrometry (MS/MS) product ion spectra documented variation in extent of glycosylation and the presence of malonate or acetate esters. Up to 10 isomers were detected for some metabolites. Malonate and acetate esters of three sesquiterpene diol glucosides and one unmodified diglucoside were purified using reversed phase semipreparative HPLC and analyzed and identified using 1D and 2D NMR and mass spectrometry. All four of the isolated products were glucosides of campheranane-2,12-diol. PMID:24333030

Ekanayaka, E A Prabodha; Li, Chao; Jones, A Daniel

2014-02-01

72

New lupane glycosides from Pulsatilla chinensis.  

PubMed

Two new lupane glycosides along with five known triterpenoids were isolated from the roots of Pulsatilla chinensis (Ranunculaceae). The structures of the new glycosides were determined to be 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl-23-hydroxybetulinic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester (pulsatilloside D, 6) and 3-O-[beta-D-glucopyranosyl(1-->4)][alpha-L-rhamnopyranosyl(1-->2)]-alpha-L-arabinopyranosyl-23-hydroxybetulinic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester (pulsatilloside E, 7) by spectroscopic analysis and chemical methods. The compounds were evaluated for cytotoxic activities against K-562 human leukemia and HeLa cells. PMID:11859478

Ye, Wencai; Zhang, Qingwen; Hsiao, Wendy W; Zhao, Shouxun; Che, Chun-Tao

2002-02-01

73

?-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. PMID:24143039

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

2013-01-01

74

Cardiac glycosides in traditional Chinese medicine  

Microsoft Academic Search

Summary  The effect of cardiac glycosides containing medicinal herbs, e.g. Ting Li Zi (Descurainia sophia), against heart failure was detected by traditional Chinese doctors at the beginning of the first century, more than 16 centuries\\u000a before Withering’s discovery of digitalis to promote diuresis. We ran infer the diagnosis from the description of the symptom\\u000a complex, for which the herb as the

Lu Fu-hua

1987-01-01

75

Benzophenone O-glycosides from Hypericum elegans  

Microsoft Academic Search

Elegaphenonoside, a new benzophenone O-rhamnoside, together with two known benzophenone O-glycosides, namely hypericophenonoside and neoannulatophenonoside, were isolated from the aerial parts of Hypericum elegans Stephan ex Willd. The structure of the new compound was established as 3?,5?,6-trihydroxy-4-methoxybenzophenone-2-O-?-L-rhamnopyranoside by means of chemical and physical evidence. In addition, the presence of kaempferol, quercetin, isoquercitrin, norathyriol, I-3,II-8-biapigenin, quercitrin, hyperoside and rutin were established

Paraskev T. Nedialkov; Dimitrina Zheleva-Dimitrova; Ulrich Girreser; Gerassim M. Kitanov

2009-01-01

76

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

77

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

78

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

79

Oleandrin: A cardiac glycosides with potent cytotoxicity  

PubMed Central

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.

2013-01-01

80

[Phenylethanoid glycosides distribution in medicinal plants of Gesneriaceae].  

PubMed

To investigate the role of distribution and phylogeny of phenylethanoid glycoside in medicinal plants of Gesneriaceae, five phenylpropanoid glycosides, acteoside, paraboside B, isonuomioside A, paraboside II, and paraboside III were quantitatively determined in 12 species of Gesneriaceae by HPLC. The existence and content of these compounds were analyzed. The results showed that phenylethanoid glycosides were found in the most of those plants, but the kind of phenylethanoid glycosides varied in different species. Acteoside distribute in most of this plant group, paraboside B, isonuomioside A, paraboside II, and paraboside III were rare in those plants. The results of this study support morphological viewpoint that Trib. Trichosporeae is more developmental than Trib. Didymocarpeae. PMID:24791528

Bai, Zhen-Fang; Wang, Xiao-Qin; Xiao, Pei-Gen; Liu, Yong

2013-12-01

81

Oxidative cyclizations, the synthesis of aryl-substituted C-glycosides, and the role of the second electron transfer step.  

PubMed

Anodic oxidation reactions have been used to synthesize aryl- and biaryl-substituted C-glycosides. The reactions take advantage of the tendency for alcohol nucleophiles to trap nonpolar radical cations. The addition of the alcohol to the radical cation appears to be reversible, and the success of the cyclizations is dependent on the ease with which the resulting benzylic radical is oxidized. PMID:24199843

Smith, Jake A; Moeller, Kevin D

2013-11-15

82

Ergot alkaloid glycosides with immunomodulatory activities  

Microsoft Academic Search

New glycosides derived from ergot alkaloids elymoclavine and DH-lysergol were synthesized by chemoenzymatic methods. ?-Glucosides were obtained either by chemical method or by transglycosylation (glycosidase from Aspergillus oryzae), lactosides were prepared by further extension of carbohydrate chain using ?-1,4-galactosyltransferase (bovine milk) and ?-5-N-acetylneuraminyl-(2?6)-?-d-galactopyranosyl-(1?4)- 2-acetamido-2-deoxy-?-d-glucopyranosyl-(1?O)-elymoclavine was prepared using ?-2,6-sialyltransferase (rat liver). Immunomodulatory activity of elymoclavine and 9,10-dihydrolysergol and their glycosylated derivatives

Vladimír K?en; Anna Fišerová; Claudine Augé; Petr Sedmera; Vladimír Havlí?ek; Petr Šíma

1996-01-01

83

Acetophenone glycosides from thyme (Thymus vulgaris L.).  

PubMed

Four acetophenone glycosides were isolated from the butanol-soluble fraction of thyme extracts. Their structures were determined by spectral methods (MS, NMR, and 2D-NMR). Among them, two new compounds, 4-hydroxyacetophenone 4-O-[5-O-(3, 5-dimethoxy-4-hydroxybenzoyl)-beta-D-apiofuranosyl]-(1-->2)-beta-D -gl ucopyranoside (1) and 4-hydroxyacetophenone 4-O-[5-O-(4-hydroxybenzoyl)-beta-D-apiofuranosyl]-(1-->2)-beta-D-+ ++gluc opyranoside (2), were determined. Compound 1 showed weak cytotoxicity, inhibiting DNA synthesis of human leukemia cells. PMID:10552470

Wang, M; Kikuzaki, H; Lin, C C; Kahyaoglu, A; Huang, M T; Nakatani, N; Ho, C T

1999-05-01

84

Flavonol glycosides of Warburgia ugandensis leaves  

Microsoft Academic Search

Four new flavonol glycosides: kaempferide 3-O-?-xylosyl (1?2)-?-glucoside, kaempferol 3-O-?-rhamnoside-7,4?-di-O-?-galactoside, kaempferol 3,7,4?-tri-O-?-glucoside and quercetin 3-O-[?-rhamnosyl (1?6)] [?-glucosyl (1?2)]-?-glucoside-7-O-?-rhamnoside, were characterized from a methanolic leaf extract of Warburgia ugandensis. The known flavonols: kaempferol, kaempferol 3-rhamnoside, kaempferol 3-rutinoside, myricetin, quercetin 3-rhamnoside, kaempferol 3-arabinoside, quercetin 3-glucoside, quercetin, kaempferol 3-rhamnoside-4?-galactoside, myricetin 3-galactoside and kaempferol 3-glucoside were also isolated. Structures were established by spectroscopic and chemical

Lawrence O. Arot Manguro; Ivar Ugi; Peter Lemmen; Rudolf Hermann

2003-01-01

85

[Caffeoyl phenylethanoid glycosides from Callicarpa kwangtungensis].  

PubMed

Phytochemical investigation on the EtOH extract from the aerial part of Callicarpa kwangtungensis led to the isolation and characterization of 10 caffeoyl phenylethanoid glycosides, 2'-acetylacteoside (1), tubuloside E (2), acteoside (3), tubuloside B (4), isoacteoside (5), alyssonoside (6), 2'-acetylforsythoside B (7), brandioside (8), forsythoside B (9), and poliumoside (10). Compound 4 was isolated from the plants of Verbenaceae,and 6 was obtained from the Callicarpa genus, for the first time, while compounds 1, 2, 5 and 7 were firstly reported from the plant. PMID:25095374

Hu, Xiao; Li, Li; Yang, Yi-Fang; Huang, Chun-Yue; Huang, Guang-Lei

2014-05-01

86

A new flavonoid glycoside from Vaccaria hispanica.  

PubMed

A profiling analysis for the methanol extract of the seeds of Vaccaria hispanica (Mill.) Rauschert was performed using a HPLC-ESI-MS technique. Five compounds were identified according to their retention times, UV spectroscopic and MS features, and by comparison with literature data. Among them, a new flavonoid glycoside, named vaccarin H, was isolated and the structure determined by spectral and chemical analysis as isovitexin 2"-O-alpha-L-arabinopyranosyl-4'-O-(6"-O-dihydroferuloyl)-3-beta-glucopyranoside. PMID:22224271

Zhang, Haijiang; Wang, Kuiwu; Wu, Jie; Chen, Yao; He, Peipei

2011-11-01

87

Cardiac glycosides of Cheiranthus allioni. XIII. Glucoerycordin  

Microsoft Academic Search

From plains erysimum (Cheiranthus allioni) Hort., (Erysimum asperum) a new cardiac glycoside has been isolated which has been called glucoerycordin. Its chemical structure has been established mainly by stepwise hydrolysis and the identification of the hydrolysis products. Glucoerycordin C41H64 O19, mp 131–135°C, [a]D20 -22.2 ± 3° (c 0.65; methanol) is 3ß-[O-ß-D-glucopyranosyl-(1 ? 4)-O-ß-D-glycopyranosyl-(1 ? 4)-gulomethylopyranosyloxy]-14,19-dihydroxy-5ß, 14ß-card-20(22)-enolide.

I. F. Makarevich; A. I. Pavlii; S. I. Makarevich

1989-01-01

88

Baccharane glycosides from seeds of Impatiens balsamina.  

PubMed

From the seeds of Impatiens balsamina have been isolated four rare baccharane glycosides, hosenkosides L-O. The structures of all isolates were secured by the use of 2D NMR techniques (1H-1H COSY, HMQC, HMBC, ROESY) and chemical derivatization. Hosenkosides L and M are hosenkol A 3-O-sambubiosyl-28-O-glucoside and 3-O-sambubiosyl-26-O-glucosyl-28-O-glucoside, respectively. Hosenkoside N is hosenkol C 3-O-glucosyl-28-O-glucoside. Hosenkoside O is hosenkol D 3-O-sophorosyl-28-O-glucoside. PMID:7765763

Shoji, N; Umeyama, A; Yoshikawa, K; Nagai, M; Arihara, S

1994-11-01

89

Deuterium NMR Investigation of the lyotropic phases of alkyl ?-glycoside/D2O systems.  

PubMed

We have investigated the phase behavior of four glycosides (?C8OGlc, ?C8SGlc, ?C10OGlc, ?C8OGal) in water and D2O by optical polarizing microscopy and deuterium NMR. Previously published phase diagrams were evaluated by deuterium NMR, via monitoring D2O spectra, and confirmed the presence of the hexagonal, bicontinuous cubic, and lamellar phases in these glycosides. We have also shown the presence of the gel phase in (?C10OGlc) and observed the extensive supercooling of the lamellar phase to temperatures well below the Kraft line. While the main features of the phase diagrams were confirmed, some phase boundaries were found to be slightly different. Magnetically aligned spectra were also observed for relatively dilute samples for the hexagonal phase (?C8OGlc and ?C8OGal) and the lamellar phase (?C8SGlc and ?C10OGlc). The average number of bound water molecules per headgroup in the lamellar phase for the glycosides was determined by the systematic measurement of the quadrupolar splitting of D2O over a wide range of values of the (glycoside/water) molar ratio. The number of water molecules bound to the headgroup was found on average to be about 1.6-1.7 water molecules with no significant differences in this value for the different glycosides (and over the temperature range investigated), indicating that the bound water content is predominately influenced by the number of hydroxyl groups of the headgroup only. However, this bound water content of only 1.6-1.7 water molecules per sugar headgroup is surprisingly low, suggesting strong intermolecular interactions of the OH groups of headgroup sugars. The results are in line with computational results reported earlier for the octyl-?-glucoside and ?-galactoside, which show the presence of strong intralayer hydrogen bonding. PMID:23718628

Misran, Omar; Timimi, Bakir A; Heidelberg, Thorsten; Sugimura, Akihiko; Hashim, Rauzah

2013-06-20

90

Verbascoside derivatives and iridoid glycosides from Penstemon crandallii  

Microsoft Academic Search

The new phenylethanoid glycosides 2-O-acetyl-3?-O-methylverbascoside and 2,4?-di-O-acetyl-3?-O-methylverbascoside were isolated and identified from Penstemon crandallii. The major iridoid glycoside was plantarenaloside and no aucubin type iridoids were found. This contrasted with a previous analysis of P. teucrioides, from the same Penstemon subsection, which was dominated by aucubin derivatives.

Lotfy D. Ismail; Mohamed M. El-Azizi; Taha I. Khalifa; Frank R. Stermitz

1995-01-01

91

Multiple defensive roles for triterpene glycosides from two Caribbean sponges  

Microsoft Academic Search

Despite their high nutritional value and a lack of physical defenses, most marine sponges appear to be minimally affected by predators, competitors, and fouling organisms, possibly due to sponge chemical defenses. In the last 15 years, several triterpene glycosides have been isolated from sponges, but their ecological or physiological roles are largely unknown. We tested triterpene glycosides from Erylus formosus

Julia Kubanek; Kristen E. Whalen; Sebastian Engel; Sarah R. Kelly; Timothy P. Henkel; William Fenical; Joseph R. Pawlik

2002-01-01

92

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

93

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

94

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. PMID:24949266

2014-01-01

95

Ergot alkaloid glycosides with immunomodulatory activities.  

PubMed

New glycosides derived from ergot alkaloids elymoclavine and DH-lysergol were synthesized by chemoenzymatic methods. beta-Glucosides were obtained either by chemical method or by transglycosylation (glycosidase from Aspergillus oryzae), lactosides were prepared by further extension of carbohydrate chain using beta-1,4-galactosyltransferase (bovine milk) and alpha-5-N-acetylneuraminyl-(2-->6)-beta-D-galactopyranosyl-(l-->4)-2- acetamido-2-deoxy-beta-D-glucopyranosyl-(1-->O)-elymoclavine was prepared using alpha-2,6-sialyltransferase (rat liver). Immunomodulatory activity of elymoclavine and 9,10-dihydrolysergol and their glycosylated derivatives on natural killer (NK) cell-mediated cytotoxicity of human resting and activated human peripheral blood mononuclear cells (PBMC) was investigated. Addition of ergot alkaloid glycosides to the mixtures of effector and target cells potentiated the PBMC cytotoxicity against both NK-sensitive and -resistant target cells. The glycoconjugates of elymoclavine enhanced cytotoxicity of PBMC against NK-resistant target cells. The glycoconjugates of DH-lysergol potentiated NK cytotoxicity of PBMC against NK-sensitive target cells. PMID:8818236

Kren, V; Fiserová, A; Augé, C; Sedmera, P; Havlícek, V; Síma, P

1996-06-01

96

Resin glycosides from Ipomoea pes-caprae.  

PubMed

Ipomoea pes-caprae (beach morning-glory; "riñonina" for the herbal drug in Mexico) is prescribed by traditional healers to moderate "heat" in an infected kidney. The hexane-soluble extract from the aerial parts of this medicinal plant, through preparative-scale recycling HPLC, yielded six new lipophilic oligosaccharides of jalapinolic acid: pescaproside B (1) and pescapreins V-IX (2-6). The previously known pescaproside A (7), pescapreins I-IV (8-11), and stoloniferin III (12) were also identified in the analyzed material by means of HPLC comparison with authentic samples. The glycosidic acid structure for all pentasaccharides was confirmed as simonic acid B. Pescaproside B (1), an acylated glycosidic acid methyl ester, is structurally related to pescaprein III (10). Pescapreins V (2) and VI (3) are diasteroisomeric tetraglycosidic lactones of operculinic acid C. Both of these compounds contain (2S)-methylbutyric and n-dodecanoic acids as their esterifying residues. Pescapreins VII (4) and IX (6) are pentasaccharides that contain an n-decanoyl group as their esterifying fatty acid residue instead of the n-dodecanoyl found in pescapreins I (8) and IV (11). Pescaprein VIII (5) represents an isomer of pescaprein II (9) containing an n-dodecanoyl unit as the esterifying residue at position C-4 of the third rhamnose moiety and a 2-methylpropanoyl at C-2 of the second rhamnose. High-field NMR spectroscopy and FAB mass spectrometry were used to characterize all new isolated compounds. PMID:17511505

Escobedo-Martínez, Carolina; Pereda-Miranda, Rogelio

2007-06-01

97

[Cardiac glycosides: From ancient history through Withering's foxglove to endogeneous cardiac glycosides].  

PubMed

For centuries, drugs that increase the power of contraction of the failing heart have been used for the treatment of congestive heart failure (dropsy). The cardiac effect is due to the content of cardiac glycosides. Squill or sea onion, Urginea (Scilla) maritima, a seashore plant, was known by the ancient Romans and Syrians and possibly also by the ancient Egyptians. Squills were used erratically, but some prescriptions indicate that they may have been used for the treatment of oedematous states. The toxic effect of strophanthus species was known from poisoned arrows used by the natives in Africa. Digitalis, derived form the foxglove plant, Digitalis purpurea, is mentioned in writings as early as 1250; a Welsh family, known as the Physicians of Myddvai, collected different herbs and digitalis was included in their prescriptions. However, the druge was used erratically until the 18th century, when William Withering, an English physician and botanist, published a monograph describing the clinical effects of an extract of the foxglove plant. Later, in 1785, the indication and the toxicity of digitalis were reported in his book, "An account of the Foxglove and some of its medical uses with practical remarks on dropsy, and other diseases". In Denmark, the leaves of Digitalis purpurea or Digitalis lanata were tested for cardiac glycoside activity. The standardized digitalis powder was used in tinctures, infusions, and tablets. The preparations were included in successive editions of the Danish pharmacopoeia, some of the tinctures already in 1828, i.e. before the standardization of the drug. Isolation of cardiac glycosides from digitalis, strophanthus and squill and determination of their chemical structures initiated biochemical and pharmacological studies. The scientific advances led to an understanding of cardiac muscle contractility and the Na,K pump as the cellular receptor for the inotropic action of digitalis. Examination of putative endogenous ligands to the receptor revealed some endogenous cardiac glycosides of similar or identical structures as those found in digitalis, strophanthus and squill. Increased concentrations of these glycosides are found in patients with heart failure. Further investigations are needed to determine whether the secretion of glycosides might be a physiologic response to a diminished cardiac output. PMID:15685783

Norn, Svend; Kruse, Poul R

2004-01-01

98

Influence of derivation on the lipophilicity and inhibitory actions of cardiac glycosides on myocardial Na+-K+-ATPase.  

PubMed Central

Lipophilicity and inhibitory actions on guinea-pig heart Na+-K+-ATPase of twenty-six digitalis and six strophanthus glycosides comprising the aglycones, mono-, bis-, tris-sugar, alkylated (acylated) tris-sugar, acyl steroid derivatives and three cardanolides were investigated. Their octanol/water partition coefficients (P), reversed phase thin layer (r.t.l.c.) and reversed phase high performance liquid chromatography (r.h.p.l.c.) were determined and the viability of these methods as a measure of the lipophilicity of the cardiotonic steroids evaluated. The influence of lipophilicity and so also structural changes on the inhibitory effects of the cardiac glycosides on myocardial Na+-K+-ATPase was then examined. It is concluded that (a) r.t.l.c. and r.h.p.l.c. are just as effective as the conventional shake-flask method for estimation of the lipophilicity of cardiac glycosides and (b) the inhibitory potencies of cardiotonic steroids on the myocardial Na+-K+-ATPase increase with growing lipophilicity. The relationship between these two parameters is, however, governed by the influence of substitution or derivation of structural components on their inhibitory potencies on the myocardial Na+-K+-ATPase. PMID:3036289

Dzimiri, N.; Fricke, U.; Klaus, W.

1987-01-01

99

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

100

Spectrophotometric estimation of individual flavone glycosides in three Euphorbia species.  

PubMed

Two spectrophotometric methods (conventional and differential) are carried out for the estimation of flavone glycosides (hyperoside and/or kaempferol-3-beta-glucoside) in Euphorbia paralias L., and Euphorbia helioscopia L. The glycosides are extracted with methanol from the aerial parts of the different Euphorbia species, separated on silica gel chromatoplates, and eluted by refluxing with methanol (80%). The absorbance value (conventional method) and the delta absorbance value (differential method) of the prepared glycosidal solutions are measured. The results of both methods are of conveinent reproducibility. PMID:1161795

Abdel-Salam, N A; El-Sayed, M; Khafagy, S M

1975-06-01

101

Flavone C-glycosides from Bryonia alba and B. dioica  

Microsoft Academic Search

Lutonarin was isolated from Bryonia alba and B. dioica. Five further C-glycosides: vitexin, isovitexin, isoorientin, saponarin were isolated from B. dioica together with saponarin caffeic ester, a new natural product.

Miroslawa Krauze-Baranowska; Wojciech Cisowski

1995-01-01

102

A new aryl glycoside from Euphorbia helioscopia L  

Microsoft Academic Search

A new aryl glycoside, 3?-O-galloyl-benzyl-O-?-l-rhamnopyranosyl-(1?6)-?-d-glucopyranoside, was isolated from Euphorbia helioscopia L., and its structure was elucidated on the basis of various spectroscopic data analysis.

Wei Sheng Feng; Li Gao; Xiao Ke Zheng; Yan Zhi Wang

2009-01-01

103

A new lathyrane diterpene glycoside from Euphorbia helioscopia L  

Microsoft Academic Search

A new lathyrane diterpene glycoside, named 3?, 7?, 15?-trihydroxy-14-oxolathyra-5E, 12E-dienyl-16-O-?-d-glucopyranoside, was isolated from Euphorbia helioscopia L. Its structure was established by spectroscopic techniques including 2D NMR.

Wei Sheng Feng; Li Gao; Xiao Ke Zheng; Yan Zhi Wang; Hui Chen

2010-01-01

104

New phenylpropanoid glycosides from Juniperus communis var. depressa.  

PubMed

Two new phenylpropanoid glycosides were isolated from the leaves and stems of Juniperus communis var. depressa (Cupressaceae) along with 14 known compounds. Their structures were determined by spectral analyses, in particular by 2D-NMR spectral evidence. PMID:20460808

Iida, Naoki; Inatomi, Yuka; Murata, Hiroko; Murata, Jin; Lang, Frank A; Tanaka, Toshiyuki; Nakanishi, Tsutomu; Inada, Akira

2010-05-01

105

Three new secoiridoid glycoside dimers from Swertia mileensis  

Microsoft Academic Search

Three new secoiridoid glycoside dimers named swerilactosides A–C (1–3) were isolated from Swertia mileensis. Their structures were elucidated based on extensive spectral analyses (1D and 2D NMR, MS, and IR spectroscopic means).

Chang-An Geng; Xue-Mei Zhang; Yun-Bao Ma; Zhi-Yong Jiang; Ji-Feng Liu; Jun Zhou; Ji-Jun Chen

2010-01-01

106

Temporal and spatial variation in cyanogenic glycosides in Eucalyptus cladocalyx  

Microsoft Academic Search

Summary The release of hydrogen cyanide from endoge- nous cyanide-containing compounds in plants is an effective herbivore deterrent. We investigated temporal and spatial vari- ations in cyanogenic glycoside concentration in greenhouse- grown seedlings and 6-year-old plantation trees of Eucalyptus cladocalyx F. Muell., which allocates up to 20% of leaf nitro- gen to the cyanogenic glycoside, prunasin. The highest cyano- genic

ROSLYN M. GLEADOW; IAN E. WOODROW

107

Secoiridoid glycoside and alkaloid constituents of Hydrangea chinensis.  

PubMed

A new secoiridoid glycoside, hydrachoside A (1), along with 14 known compounds, was isolated from the leaves of Hydrangea chinensis. The absolute stereochemistry of the side chain attached to C-15 on the secoiridoid glycoside hydrangenoside E (2) was determined by NMR spectral analysis. The structures of compounds 1 and 2 were elucidated on the basis of spectral data. The previously reported structure, hydrachine A (3), was revised as its epimer, (-)-neodichroine (4), a new compound. PMID:14510608

Chang, Fang-Rong; Lee, Yue-Han; Yang, Yu-Liang; Hsieh, Pei-Wen; Khalil, Ashraf T; Chen, Chung-Yi; Wu, Yang-Chang

2003-09-01

108

Trial watch: Cardiac glycosides and cancer therapy.  

PubMed

Cardiac glycosides (CGs) are natural compounds sharing the ability to operate as potent inhibitors of the plasma membrane Na(+)/K(+)-ATPase, hence promoting-via an indirect mechanism-the intracellular accumulation of Ca(2+) ions. In cardiomyocytes, increased intracellular Ca(2+) concentrations exert prominent positive inotropic effects, that is, they increase myocardial contractility. Owing to this feature, two CGs, namely digoxin and digitoxin, have extensively been used in the past for the treatment of several cardiac conditions, including distinct types of arrhythmia as well as contractility disorders. Nowadays, digoxin is approved by the FDA and indicated for the treatment of congestive heart failure, atrial fibrillation and atrial flutter with rapid ventricular response, whereas the use of digitoxin has been discontinued in several Western countries. Recently, CGs have been suggested to exert potent antineoplastic effects, notably as they appear to increase the immunogenicity of dying cancer cells. In this Trial Watch, we summarize the mechanisms that underpin the unsuspected anticancer potential of CGs and discuss the progress of clinical studies that have evaluated/are evaluating the safety and efficacy of CGs for oncological indications. PMID:23525565

Menger, Laurie; Vacchelli, Erika; Kepp, Oliver; Eggermont, Alexander; Tartour, Eric; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

2013-02-01

109

Mechanism of neurotoxicity of cardiotonic glycosides.  

PubMed

1 In cats intracerebroventricular administration of 5, 10, 20 mug of peruvoside, a cardiac glycoside obtained from the plant, Thevetia neriifolia, and 10 and 20 mug of ouabain, produced marked neurotoxicity. This was dose-related. 2 Prior administration reserpine (2 mg/kg i.m., 500 mug i.c.v.) or tetrabenazine (25 mg/kg i.v., 50 mg/kg i.v. and 2 mg/,g i.c.v.) suppressed the neurotoxicity, but lithium carbonate (100 mg/,g i.p., 2 mg 2.c.v.) and haloperidol (200 mug i.c.v.) were ineffective. 3 Prior administration of 2-bromolysergic acid diethylamide (BOL-148, 200 mug i.c.v.) or p-chlorophenylalanine (PCPA) (400 mg/kg i.p.) suppressed the neurotoxicity induced by peruvoside and ouabain. 4 Perfusion of the lateral ventricles of cats with 10, 20 and 30 mug of peruvoside or ouqbain produced a massive release of 5-hydroxytryptamine (5-HT). This was dose-related. Prior administration PCPA suppressed the release of 5-HT. 5 The results of the findings indicate the involvement of 5-HT in the genesis of neurotoxicity induced by peruvoside or ouabain. PMID:13903

Gaitondé, B B; Joglekar, S N

1977-02-01

110

Mechanism of neurotoxicity of cardiotonic glycosides.  

PubMed Central

1 In cats intracerebroventricular administration of 5, 10, 20 mug of peruvoside, a cardiac glycoside obtained from the plant, Thevetia neriifolia, and 10 and 20 mug of ouabain, produced marked neurotoxicity. This was dose-related. 2 Prior administration reserpine (2 mg/kg i.m., 500 mug i.c.v.) or tetrabenazine (25 mg/kg i.v., 50 mg/kg i.v. and 2 mg/,g i.c.v.) suppressed the neurotoxicity, but lithium carbonate (100 mg/,g i.p., 2 mg 2.c.v.) and haloperidol (200 mug i.c.v.) were ineffective. 3 Prior administration of 2-bromolysergic acid diethylamide (BOL-148, 200 mug i.c.v.) or p-chlorophenylalanine (PCPA) (400 mg/kg i.p.) suppressed the neurotoxicity induced by peruvoside and ouabain. 4 Perfusion of the lateral ventricles of cats with 10, 20 and 30 mug of peruvoside or ouqbain produced a massive release of 5-hydroxytryptamine (5-HT). This was dose-related. Prior administration PCPA suppressed the release of 5-HT. 5 The results of the findings indicate the involvement of 5-HT in the genesis of neurotoxicity induced by peruvoside or ouabain. PMID:13903

Gaitonde, B B; Joglekar, S N

1977-01-01

111

Antioxidant flavonol glycosides from Schinus molle.  

PubMed

Chromatographic separation of aqueous MeOH extract of the leaves of Schinus molle L. has yielded two new acylated quercetin glycosides, named isoquercitrin 6''-O-p-hydroxybenzoate (12) and 2''-O-alpha-L-rhamnopyranosyl-hyperin 6''-O-gallate (13), together with 12 known polyphenolic metabolites for the first time from this species, namely gallic acid (1), methyl gallate (2), chlorogenic acid (3), 2''-alpha-L-rhamnopyranosyl-hyperin (4), quercetin 3-O-beta-D-neohesperidoside (5), miquelianin (6), quercetin 3-O-beta-D-galacturonopyranoside (7), isoquercitrin (8), hyperin (9), isoquercitrin 6''-gallate (10), hyperin 6''-O-gallate (11) and (+)-catechin (14). Their structures were established on the basis of chromatographic properties, chemical, spectroscopic (UV, 1H, 13C NMR) and ESI-MS (positive and negative modes) analyses. Compounds 4-9 and 11 exhibited moderate to strong radical scavenging properties on lipid peroxidation, hydroxyl radical and superoxide anion generations with the highest activities shown by 6 and 7 in comparison with that of quercetin as a positive control in vitro. PMID:16521111

Marzouk, Mohamed S; Moharram, Fatma A; Haggag, Eman G; Ibrahim, Magda T; Badary, Osama A

2006-03-01

112

Cyanogenic glycosides: synthesis, physiology, and phenotypic plasticity.  

PubMed

Cyanogenic glycosides (CNglcs) are bioactive plant products derived from amino acids. Structurally, these specialized plant compounds are characterized as ?-hydroxynitriles (cyanohydrins) that are stabilized by glucosylation. In recent years, improved tools within analytical chemistry have greatly increased the number of known CNglcs by enabling the discovery of less abundant CNglcs formed by additional hydroxylation, glycosylation, and acylation reactions. Cyanogenesis--the release of toxic hydrogen cyanide from endogenous CNglcs--is an effective defense against generalist herbivores but less effective against fungal pathogens. In the course of evolution, CNglcs have acquired additional roles to improve plant plasticity, i.e., establishment, robustness, and viability in response to environmental challenges. CNglc concentration is usually higher in young plants, when nitrogen is in ready supply, or when growth is constrained by nonoptimal growth conditions. Efforts are under way to engineer CNglcs into some crops as a pest control measure, whereas in other crops efforts are directed toward their removal to improve food safety. Given that many food crops are cyanogenic, it is important to understand the molecular mechanisms regulating cyanogenesis so that the impact of future environmental challenges can be anticipated. PMID:24579992

Gleadow, Roslyn M; Møller, Birger Lindberg

2014-01-01

113

One-pot hydrothermal synthesis of peony-like Ag/Ag0.68V2O5 hybrid as high-performance anode and cathode materials for rechargeable lithium batteries  

NASA Astrophysics Data System (ADS)

A peony-like Ag/Ag0.68V2O5 hybrid assembled from nanosheets with the thickness of 40 nm was synthesized through a one-pot hydrothermal approach from vanadium pentoxide (V2O5), oxalic acid (H2C2O4), and silver nitrate (AgNO3) at 180 °C for 24 h. The hybrid exhibits high performance as both anode and cathode materials for rechargeable lithium batteries. Electrochemical measurements revealed that the as-prepared Ag/Ag0.68V2O5 hybrid displayed excellent cycling stability, especially as an anode material. The resulting anode retains 100% of the initial capacity after 1000 cycles under a current density of 400 mA g-1. This phenomenon may be attributed to electron conductivity improvement by the existence of metallic silver in the hybrid in addition to the convenient access to lithium ion ingress/egress because of its unique structure.A peony-like Ag/Ag0.68V2O5 hybrid assembled from nanosheets with the thickness of 40 nm was synthesized through a one-pot hydrothermal approach from vanadium pentoxide (V2O5), oxalic acid (H2C2O4), and silver nitrate (AgNO3) at 180 °C for 24 h. The hybrid exhibits high performance as both anode and cathode materials for rechargeable lithium batteries. Electrochemical measurements revealed that the as-prepared Ag/Ag0.68V2O5 hybrid displayed excellent cycling stability, especially as an anode material. The resulting anode retains 100% of the initial capacity after 1000 cycles under a current density of 400 mA g-1. This phenomenon may be attributed to electron conductivity improvement by the existence of metallic silver in the hybrid in addition to the convenient access to lithium ion ingress/egress because of its unique structure. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr00250d

Wei, Denghu; Li, Xiaona; Zhu, Yongchun; Liang, Jianwen; Zhang, Kailong; Qian, Yitai

2014-04-01

114

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

115

Steviol glycoside safety: is the genotoxicity database sufficient?  

PubMed

The safety of steviol glycoside sweeteners has been extensively reviewed in the literature. National and international food safety agencies and approximately 20 expert panels have concluded that steviol glycosides, including the widely used sweeteners stevioside and rebaudioside A, are not genotoxic. However, concern has been expressed in recent publications that steviol glycosides may be mutagenic based on select studies representing a small fraction of the overall database, and it has been suggested that further in vivo genotoxicity studies are required to complete their safety profiles. To address the utility of conducting additional in vivo genotoxicity studies, this review evaluates the specific genotoxicity studies that are the sources of concern, and evaluates the adequacy of the database including more recent genotoxicity data not mentioned in those publications. The current database of in vitro and in vivo studies for steviol glycosides is robust and does not indicate that either stevioside or rebaudioside A are genotoxic. This, combined with a lack of evidence for neoplasm development in rat bioassays, establish the safety of all steviol glycosides with respect to their genotoxic/carcinogenic potential. PMID:23103588

Urban, J D; Carakostas, M C; Brusick, D J

2013-01-01

116

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

117

Two new flavonol glycosides from Dimocarpus longan leaves.  

PubMed

From the extracts of Dimocarpus longan Lour leaves, 2 unusual flavonol glycosides, quercetin 3-O-(3?-O-2?-methyl-2?-hydroxylethyl)-?-d-xyloside (1) and quercetin 3-O-(3?-O-2?-methyl-2?-hydroxylethyl)-?-l-rhamnopyranoside (2), as well as 10 known compounds including 2 flavonol glycosides, afzelin (3) and kaempferol-3-O-?-l-rhamnopyranoside (4), 2 flavans, ( - )-epicatechin (5) and proanthocyanidin A-2 (6), 3 triterpenoids, friedelin (7), epifriedelanol (8) and ?-amyrin (9), a peptide, N-benzoylphenylalanyl-N-benzoylphenylalaninate (10), and 2 sterols, ?-sitosterol (11) and daucosterol (12) were isolated and identified by using combination of mass spectrometry and various 1D and 2D NMR techniques. This is the first report of flavonoid glycosides possessing a 2-methyl-2-hydroxylethoxyl group in sugar moiety from D. longan. PMID:25325562

Xue, Yongmei; Wang, Wenjing; Liu, Yujiao; Zhan, Rui; Chen, Yegao

2015-01-01

118

3-Hydroxy-3-methylglutaryl flavonol glycosides from Oxytropis falcata.  

PubMed

Five new 3-hydroxy-3-methylglutaryl (HMG) flavonol 3-O-glycosides, named oxytroflavosides A-E (1-5), and two new rhamnocitrin 3-O-glycosides, oxytroflavosides F and G (6 and 7) were isolated from the n-BuOH-soluble fraction of an EtOH extract of Oxytropis falcata together with seven known kaempferol glycosides (8-14), of which six were isolated from the genus Oxytropis for the first time. The structures of these compounds were elucidated by spectroscopic techniques and chemical methods. The absolute configuration of HMG in compounds 1-5 was determined to be S through spectroscopic analysis of the mevalonamide obtained by amidation and reduction of the HMG moiety. Compounds 1-10 were evaluated for anti-inflammatory activities using lipopolysaccharide-induced RAW 264.7 cells, but none of them showed inhibitory effects on NO production. PMID:22775441

Wang, Shan-Shan; Zhang, Xiao-Jing; Que, Sheng; Tu, Guang-Zhong; Wan, Dan; Cheng, Wei; Liang, Hong; Ye, Jia; Zhang, Qing-Ying

2012-07-27

119

Xanthone glycosides from Swertia bimaculata with ?-glucosidase inhibitory activity.  

PubMed

Seven new xanthone glycosides (1-7) were isolated from the n-butanol extract of Swertia bimaculata, together with six known compounds (8-13). Their structures were elucidated on the basis of extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. All the compounds were evaluated for their ?-glucosidase inhibitory activities in vitro, and compounds 3, 4, and 7 exhibited significant activities to inhibit ?-glucosidase. Meanwhile the effects of different substitutions on the ?-glucosidase inhibitory activity of xanthone glycosides from S. bimaculata are also discussed. PMID:24687743

Yue, Yao-Dong; Zhang, Yu-Tang; Liu, Zhao-Xia; Min, Qiu-Xia; Wan, Luo-Sheng; Wang, Yong-Long; Xiao, Zuo-Qi; Chen, Jia-Chun

2014-04-01

120

Three new steroid glycosides from the starfish Asterina pectinifera.  

PubMed

Three new steroid glycosides, pectiniosides H-J (1-3), were isolated along with three known compounds (4-6) including a steroid glycoside and two polyhydroxysteroids, from the alcoholic extract of the starfish Asterina pectinifera. The structures of 1-3 were determined by extensive NMR and HR-ESI-MS experiments. Compounds 1-4 did not show cytostatic activity on HL-60 cells below 100 ?M, while compounds 5-6 showed moderate cytostatic activity, with IG50 values of 80.3 and 40.5 ?M, respectively. PMID:23339622

Li, Zhanqiang; Chen, Gang; Lu, Xuan; Wang, Haifeng; Feng, Baomin; Pei, Yuehu

2013-10-01

121

Further flavonol and iridoid glycosides from Ajuga remota aerial parts  

Microsoft Academic Search

Five new iridoid glycosides characterised as 6-keto-8-acetylharpagide (1), 6,7-dehydro-8-acetylharpagide (2), 7,8-dehydroharpagide (3), 8-acetylharpagide-6-O-?-glucoside (4), harpagide-6-O-?-glucoside (5) together with three flavonol glycosides, myricetin 3-O-rutinoside-4?-O-rutinoside (6), myricetin 3-O-rutinoside-3?-O-rutinoside (7) and isorhamnetin 3-O-rutinoside-7-O-rutinoside-4?-O-?-glucoside (8) have been isolated from the aerial parts of Ajuga remota. Also isolated were two known compounds ajugarin IV and ajugarin V. Their structures were established using spectroscopic methods including

LAWRENCE ONYANGO AROT Manguro; JOSEPH ACHOLA Ogur; DENNIS MAGIO Okora; SAMUEL OTIENO Wagai; PETER Lemmen

2007-01-01

122

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

123

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

124

A Comparison of Sample Preparation Techniques for Quantifying Iridoid Glycosides Sequestered by Lepidopteran Larvae  

Microsoft Academic Search

This study compared different methods of tissue preparation for extraction of iridoid glycosides sequestered by three species\\u000a of lepidopteran larvae. Junonia coenia is a specialist on plant species that produce iridoid glycosides, while the arctiids Estigmene acrea and Spilosoma congrua are both polyphagous and will eat plants that produce iridoid glycosides. Larvae of all three species were reared on leaves

Evan C. Lampert; M. Deane Bowers

2011-01-01

125

Cooperative catalysis in glycosidation reactions with O-glycosyl trichloroacetimidates as glycosyl donors.  

PubMed

Thiourea mediates cooperative glycosidation through hydrogen bonding. N,N'-Diarylthiourea as cocatalyst enforces an SN2-type acid-catalyzed glycosidation even at room temperature (see scheme; Bn=benzyl). From O-(?-glycosyl) trichloroacetimidates as glycosyl donors and various acceptors, ?-glycosides are preferentially or exclusively obtained. PMID:23893796

Geng, Yiqun; Kumar, Amit; Faidallah, Hassan M; Albar, Hassan A; Mhkalid, Ibrahim A; Schmidt, Richard R

2013-09-16

126

Bioactive saponins and glycosides. XXVII. Structures of new cucurbitane-type triterpene glycosides and antiallergic constituents from Citrullus colocynthis.  

PubMed

The methanolic extract from the fruit of Citrullus colocynthis showed an inhibitory effect on ear passive cutaneous anaphylaxis reactions as a type I allergic model in mice. From the methanolic extract, two new cucurbitane-type triterpene glycosides, colocynthosides A and B, were isolated together with 17 known constituents. The structures of colocynthosides A and B were elucidated on the basis of chemical and physicochemical evidence. In addition, the principal cucurbitane-type triterpene glycoside, cucurbitacin E 2-O-beta-D-glucopyranoside, and its aglycon, cucurbitacin E, exhibited the antiallergic activity at a dose of 100 and 1.25 mg/kg, p.o., respectively. PMID:17329885

Yoshikawa, Masayuki; Morikawa, Toshio; Kobayashi, Hisanori; Nakamura, Akihiko; Matsuhira, Koudai; Nakamura, Seikou; Matsuda, Hisashi

2007-03-01

127

Triterpene glycosides from the Far-Eastern sea cucumber Pentamera calcigera. 1. Monosulfated glycosides and cytotoxicity of their unsulfated derivatives.  

PubMed

Three new monosulfated triterpene glycosides, calcigerosides B (2), C(1) (3), and C(2) (4), along with the known cucumarioside G(2) (1), have been isolated from the sea cucumber Pentamera calcigera. Their structures have been deduced from extensive spectral analysis (NMR and MS) and chemical evidence. Compounds 2-4 present a novel pentasacharide chain never reported before in sea cucumber triterpene glycosides. The desulfated derivatives of calcigerosides B, C(1), and C(2) (5, 7, and 9, respectively) showed moderate cytotoxicity (IC(50) = 5 microg/mL) against a selection of four human and mouse tumor cell lines. PMID:10650081

Avilov, S A; Antonov, A S; Drozdova, O A; Kalinin, V I; Kalinovsky, A I; Stonik, V A; Riguera, R; Lenis, L A; Jiménez, C

2000-01-01

128

Quantitative HPLC analysis of cardiac glycosides in Digitalis purpurea leaves.  

PubMed

An analytical method for the determination of cardiac glycosides in Digitalis purpurea leaves by hplc was developed. Quantitation was carried out by the incorporation of lanatoside A as an internal standard. The present method is sufficiently precise and relatively simple. PMID:7673934

Ikeda, Y; Fujii, Y; Nakaya, I; Yamazaki, M

1995-06-01

129

Flavones and flavonol glycosides from Eupatorium cannabinum L.  

PubMed

The 6-methoxyflavones hispidulin and eupafolin have been identified for the first time from the aerial parts of Eupatorium cannabinum L. The presence of the previously known flavonol glycosides astragalin, kaempferol-3-rutinoside, hyperoside, isoquercitrin and rutin could be confirmed. Hispidulin, eupafolin and rutin were screened for cytotoxicity in vitro. PMID:2594467

Elema, E T; Schripsema, J; Malingré, T M

1989-10-20

130

Three new hecogenin glycosides from fermented leaves of Agave americana  

Microsoft Academic Search

Eight steroidal compounds, including three new hecogenin glycosides, agamenosides D–F, were isolated from the fermented leaves of Agave americana. The structures of the new steroidal saponins were elucidated by spectroscopic data and chemical methods. The activity of the isolated compounds on deformations of mycelia germinated from conidia of Pyricularia oaryzae P-2b was evaluated.

Jian-Ming Jin; Xi-Kui Liu; Chong-Ren Yang

2003-01-01

131

Chemical analysis of phenolic glycosides: art, facts, and artifacts  

Microsoft Academic Search

Phenolic glycosides have been the subject of considerable interest in recent ecological and systematic studies, especially those involving the Salicaceae. But these compounds are markedly labile in aqueous media, and the consequences of spontaneous degradation for valid interpretation of results have been largely ignored by researchers. We found that freeze-drying and oven-drying of leaf samples from several Populus and Salix

R. L. Lindroth; M. S. Pajutee

1987-01-01

132

The distribution of phenylpropanoid glycosides in Chilean calceolaria Spp  

Microsoft Academic Search

The distribution of phenylpropanoid glycosides in Chilean species of Calceolaria belonging to Reiche's section III was investigated by HPLC. Verbascoside, calceolariosides A-E, forsythoside A and isoarenarioside were detected. All species investigated contained verbascoside and\\/or calceolarioside A. The patterns of these phenolic constituents seem to be characteristic of species and groups of species rather than of higher infrageneric taxa.

Antonella Di Fabio; Alessandro Bruni; Ferruccio Poli; Juan A. Garbarino; Maria C. Chamy; Marisa Piovano; Marcello Nicoletti

1995-01-01

133

Verbascoside Derivatives and Iridoid Glycosides from Verbascum Undulatum  

Microsoft Academic Search

On further phytochemical investigation of the aerial parts of Verbascum undulatum, a new iridoid glycoside, 6-O-[3-O-(trans-feruloyl)-?-L-rhamnopyranosyl] aucubin (1) and a new verbascoside derivative, 6-O-acetyl-martynoside (2) were isolated. These structures were determined by spectral methods, mainly by 1D and 2D NMR spectroscopy.

P. Magiatis; S. Mitaku; E. Tsitsa; A. L. Skaltsounis; C. Harvala

1998-01-01

134

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/ PMID:21622642

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

2011-01-01

135

Pentasaccharide glycosides from the roots of Ipomoea murucoides.  

PubMed

Five pentasaccharide glycosides, murucins 1-5 (1-5), were isolated from the roots of the arboreal species Ipomoea murucoides, and their structures were elucidated by spectroscopic and chemical methods. Compounds 1-5 were evaluated for cytotoxicity against a small panel of cancer cell lines. PMID:16124750

León, Ismael; Enríquez, Raúl G; Nieto, David A; Alonso, Daniel; Reynolds, William F; Aranda, Eduardo; Villa, Josué

2005-08-01

136

Characterization of pentasaccharide glycosides from the roots of Ipomoea arborescens.  

PubMed

Ten new pentasaccharide glycosides, arboresins 1-6 (1-6) and murucins 6-9 (8-11), along with five known glycolipids, were isolated from the roots of Ipomoea arborescens, and their structures were elucidated by spectroscopic and chemical methods. Compounds 1-6 and 8-11 were evaluated for cytotoxicity against a small panel of cancer cell lines. PMID:16792407

León, Ismael; Mirón, Gumersindo; Alonso, Daniel

2006-06-01

137

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

138

Steroidal glycosides from the aerial part of Asclepias incarnata  

Microsoft Academic Search

The aerial part of Asclepias incarnata afforded 34 pregnane glycosides. These were confirmed to have lineolon, isolineolon, ikemagenin, 12-O-nicotinoyllineolon, deacylmetaplexigenin, metaplexigenin, rostratamine, 12-O-acetyllineolon, 15?-hydroxylineolon and 15?-hydroxyisolineolon moieties as their aglycones, and 2,6-dideoxyhexopyranose, glucopyranose and allopyranose as the corresponding sugar constituents. Their structures were determined using both spectroscopic and chemical methods.

Tsutomu Warashina; Tadataka Noro

2000-01-01

139

A biflavonoid glycoside from Lomatogonium carinthiacum (Wulf) Reichb.  

PubMed

A biflavonoid glycoside with a new carbon skeleton, named carinoside A, was isolated from the n-BuOH crude extract of the whole plant of Lomatogonium carinthiacum (Wulf) Reichb. The structure of the new compound was elucidated by using spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques. PMID:25260189

Wang, Qinghu; Han, Narenchaoketu; Wu, Xiaolan; Tai, Wenquan; Dai, Nayintai; Wu, Rongjun; Wu, Jiesi; Bao, Bagenna

2015-01-01

140

Functional genomic analysis of Arabidopsis thaliana glycoside hydrolase family 1  

Microsoft Academic Search

In plants, Glycoside Hydrolase (GH) Family 1 ß-glycosidases are believed to play important roles in many diverse processes including chemical defense against herbivory, lignification, hydrolysis of cell wall-derived oligosaccharides during germination, and control of active phytohormone levels. Completion of the Arabidopsis thalianagenome sequencing project has enabled us, for the first time, to determine the total number of Family 1 members

Zhiwei Xu; Luis Escamilla-Treviño; Lihui Zeng; Mallikarjun Lalgondar; David Bevan; Brenda Winkel; Ali Mohamed; Chi-Lien Cheng; Ming-Che Shih; Jonathan Poulton; Asim Esen

2004-01-01

141

Reversible Sterilization  

ERIC Educational Resources Information Center

Notes that difficult questions arise concerning the use of sterilization for alleged eugenic and euthenic purposes. Thus, how reversible sterilization will be used with relation to the poor, mentally ill, mentally retarded, criminals, and minors, is questioned. (Author/AM)

Largey, Gale

1977-01-01

142

Discovery of 4-functionalized phenyl-O-beta-D-glycosides as a new class of mushroom tyrosinase inhibitors.  

PubMed

A series of 4-functionalized phenyl-O-beta-D-glycosides were designed, synthesized and evaluated as a new class of mushroom tyrosinase inhibitors. The results demonstrated that compounds 6a-13a bearing a thiosemicarbazide moiety exhibited potent activities with IC50 values range from 0.31 to 52.8 microM. Particularly, compound 9a containing acetylated glucose moiety was found to be the most active molecule with an IC50 value of 0.31 microM. SARs analysis suggested that (1) the thiosemicarbazide moiety remarkably contributed to the increase of inhibitory effects on tyrosinase; (2) the configuration and bond type of sugar moiety also played a very important role in determining their inhibitory activities. The inhibition kinetics and inhibition mechanism study revealed that compound 9a was reversible and competitive type inhibitor, whereas compound 13a was reversible and competitive-uncompetitive mixed-II type inhibitor. PMID:19800229

Yi, Wei; Cao, Rihui; Wen, Huan; Yan, Qin; Zhou, Binhua; Ma, Lin; Song, Huacan

2009-11-01

143

Role of Glycoside Phosphorylases in Mannose Foraging by Human Gut Bacteria*  

PubMed Central

To metabolize both dietary fiber constituent carbohydrates and host glycans lining the intestinal epithelium, gut bacteria produce a wide range of carbohydrate-active enzymes, of which glycoside hydrolases are the main components. In this study, we describe the ability of phosphorylases to participate in the breakdown of human N-glycans, from an analysis of the substrate specificity of UhgbMP, a mannoside phosphorylase of the GH130 protein family discovered by functional metagenomics. UhgbMP is found to phosphorolyze ?-d-Manp-1,4-?-d-GlcpNAc-1,4-d-GlcpNAc and is also a highly efficient enzyme to catalyze the synthesis of this precious N-glycan core oligosaccharide by reverse phosphorolysis. Analysis of sequence conservation within family GH130, mapped on a three-dimensional model of UhgbMP and supported by site-directed mutagenesis results, revealed two GH130 subfamilies and allowed the identification of key residues responsible for catalysis and substrate specificity. The analysis of the genomic context of 65 known GH130 sequences belonging to human gut bacteria indicates that the enzymes of the GH130_1 subfamily would be involved in mannan catabolism, whereas the enzymes belonging to the GH130_2 subfamily would rather work in synergy with glycoside hydrolases of the GH92 and GH18 families in the breakdown of N-glycans. The use of GH130 inhibitors as therapeutic agents or functional foods could thus be considered as an innovative strategy to inhibit N-glycan degradation, with the ultimate goal of protecting, or restoring, the epithelial barrier. PMID:24043624

Ladevèze, Simon; Tarquis, Laurence; Cecchini, Davide A.; Bercovici, Juliette; André, Isabelle; Topham, Christopher M.; Morel, Sandrine; Laville, Elisabeth; Monsan, Pierre; Lombard, Vincent; Henrissat, Bernard; Potocki-Véronèse, Gabrielle

2013-01-01

144

Resin glycosides. XV. Simonins I-V, ether-soluble resin glycosides (jalapins) from the roots of Ipomoea batatas (cv. Simon).  

PubMed

Five new ether-soluble resin glycosides (jalapins), simonins I-V, have been isolated from the roots of Ipomoea batatas and characterized on the bases of chemical and spectral data. Simonin I is the first example of resin glycoside with aromatic acid (trans-cinnamic acid) as a component organic acid. PMID:1294318

Noda, N; Yoda, S; Kawasaki, T; Miyahara, K

1992-12-01

145

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

146

Flavonol and iridoid glycosides of Ajuga remota aerial parts  

Microsoft Academic Search

Six flavonol glycosides characterised as myricetin 3-O-?-rhamnosyl-(1??2?)-?-rhamnoside-3?-O-?-rhamnoside, 5?-O-methylmyricetin 3-O-[?-rhamnosyl (1??2?)][?-rhamnosyl (1???4?)]-? -glucoside-3?-O-?-glucoside, 5?-O-methylmyricetin 3-O-?-rhamnosyl (1??2?)-?-rhamnoside 3?-O-?-galactoside, kaemferol 3-O-rutinoside-7-O-rutinoside, myricetin 3-O-rutinoside-3?-O-?-rhamnoside, myricetin 3-O-?-glucosyl (1??2?)-?-glucoside-4?-O-?-glucoside together with two iridoid glycosides identified as 6,8-diacetylharpagide and 6,8-diacetylharpagide-1-O-?-(3?,4?-di-O-acetylglucoside) have been isolated from extract of Ajuga remota aerial parts. Also isolated from the same extract were known compounds; kaempferol 3-O-?-rhamnoside, quercetin 3-O-?-glucoside, quercetin 3-O-rutinoside, 8-acetylharpagide, ajugarin

Lawrence O. Arot Manguro; Samuel Otieno Wagai; Peter Lemmen

2006-01-01

147

Structures of the novel diterpene glycosides from Stevia rebaudiana.  

PubMed

From the commercial extract of the leaves of Stevia rebaudiana, two new diterpenoid glycosides were isolated besides the known steviol glycosides including stevioside, rebaudiosides A-F, rubusoside, and dulcoside A. The structures of the two new compounds were identified as 13-[(2-O-6-deoxy-?-d-glucopyranosyl-?-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid ?-d-glucopyranosyl ester (1), and 13-[(2-O-6-deoxy-?-d-glucopyranosyl-3-O-?-d-glucopyranosyl-?-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid ?-d-glucopyranosyl ester (2), on the basis of extensive NMR and MS spectral data as well as chemical studies. PMID:21489412

Chaturvedula, Venkata Sai Prakash; Prakash, Indra

2011-06-01

148

Two minor diterpene glycosides from the leaves of Stevia rebaudiana.  

PubMed

Two new new diterpene glycosides, 13-[(2-O-(6-O-beta-D-glucopyranosyl)-beta-D-glucopyranosyl-beta-D-glucopyranosyl)oxy] kaur-16-en-18-oic acid beta-D-glucopyranosyl ester (1) and 13-[(2-O-beta-D-glucopyranosyl-3-O-beta-D-fructofuranosyl-beta-D-glucopyranosyl)oxy] kaur-16-en-18-oic acid beta-D-glucopyranosyl ester (2) were isolated from the leaves of Stevia rebaudiana, along with the known steviol glycosides stevioside, rebaudiosides A-F and dulcoside A. The structures of the two new compounds were established on the basis of extensive 2D NMR (COSY, HSQC, and HMBC), MS and chemical studies. PMID:21425668

Chaturvedula, Venkata Sai Prakash; Rhea, Joshua; Milanowski, Dennis; Mocek, Ulla; Prakash, Indra

2011-02-01

149

Resin glycosides from the flowers of Ipomoea murucoides.  

PubMed

The CHCl(3)-soluble extract from the flowers of the Mexican medicinal plant Ipomoea murucoides, through preparative-scale recycling HPLC, yielded murucoidins I-V (1-5), which are new pentasaccharides of jalapinolic acid, as well as the known stoloniferin I (6). Saponification of the crude resin glycoside mixture yielded two glycosidic acids, simonic acid B (9) and operculinic acid A (10), and their esterifying residues were composed of the two short-chain fatty acids, 2-methylpropanoic and (2S)-methylbutyric acids. All the isolated compounds (1-6) were characterized through high-field NMR spectroscopy. Compound 4 exhibited marginal cytotoxicity against Hep-2 cells (ED(50) 4 microg/mL). PMID:16643033

Chérigo, Lilia; Pereda-Miranda, Rogelio

2006-04-01

150

Diterpene glycosides from the seeds of Pharbitis nil.  

PubMed

Six new ent-kaurane diterpene glycosides, pharbosides A-F (1-6), and a new ent-gibbane diterpene glycoside, pharboside G (7), together with three known ent-kaurane diterpenoids, 7beta,16beta,17-trihydroxy-ent-kauran-6alpha,19-olide (8), 6beta,7beta,16alpha,17-tetrahydroxy-ent-kauranoic acid (9), and 6beta,7beta,16beta,17-tetrahydroxy-ent-kauranoic acid (10), were isolated from an ethanolic extract of the seeds of Pharbitis nil. The structures of the new compounds were determined by spectroscopic methods including 1D and 2D NMR analysis. The absolute configurations of the compounds were clarified by CD spectroscopic studies. Full NMR data assignments of the three known compounds (8-10) are reported. The isolated compounds were evaluated for their cytotoxic activities against four human cancer cell lines. PMID:19435339

Kim, Ki Hyun; Choi, Sang Un; Lee, Kang Ro

2009-06-01

151

Glycosides and xanthine oxidase inhibitors from Conyza bonariensis.  

PubMed

Fractionation of the xanthine oxidase inhibitory methanol extract of Conyza bonariensis afforded three glycosides, in addition to nine known compounds including amyrin, beta-sitostero1 daucosterol, syringic acid 3-hydroxy-5-methoxybenzoic acid, eugenol 4-O-glucopyranoside, and luteolin, apigenin and takakin 8-O-glucuronide. The structures of the glycosides were established by a combination of spectroscopic methods (IR, MS, 1H and 13C NMR, DEPT, COSY, HMQC and HMBC) as 4-hydroxypyridin-3-carboxylic acid 4-O-glucopyranoside, 8-hydroxy-6,7-dihydrolinalool 8-O-glucopyranoside and bonaroside [viz. 1,3,4,12-tetrahydroxy-2-(9-hexadecenoylamino)octadecane 1-O-glucopyranoside]. The in vitro enzyme assay showed that syringic acid and takakin 8-O-glucuronide displayed weak inhibitory activity against xanthine oxidase with IC50 values of 500+/-41 microM and 170+/-12 microM, respectively. PMID:11576616

Kong, L D; Abliz, Z; Zhou, C X; Li, L J; Cheng, C H; Tan, R X

2001-10-01

152

Cardiac glycosides from the bark of Antiaris toxicaria.  

PubMed

Five new cardiac glycosides (1-5, namely antiaroside Y-ZC) together with 19 known compounds were obtained from the bark of Antiaris toxicaria. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR (HSQC, (1)H-(1)H COSY, HMBC, ROESY). The absolute configuration of sugar unit was defined by acid hydrolysis and appropriate derivatization. Compound 1 was rare 5?-H-10?-H-19-nor-cardenolide, which might derive from decarboxylative derivative of 19-COOH cardenolide. The inhibitory effects of cardiac glycosides 1-11 on the viability of NIH-H460 lung cancer cells and their induction of Nur77 expression were evaluated and preliminary structure-activity relationship (SAR) was also discussed. PMID:24879902

Li, Xiao-San; Hu, Meng-Jie; Liu, Jie; Liu, Qian; Huang, Zhi-Xing; Li, Shun-Lin; Hao, Xiao-Jiang; Zhang, Xiao-Kun; Yao, Xin-Sheng; Tang, Jin-Shan

2014-09-01

153

Flavonol glycosides with ?-D-aldohexoses from Rhododendron irroratum  

Microsoft Academic Search

Two new flavonol glycosides which contain rare ?-D-galactose or ?-D-glucose were obtained from the flowers of Rhododendron irroratum Franch., namely myricetin 3-O-?-D-galactoside-3?-O-?-D-glucoside (1) and myricetin 3-O-?-D-galactoside-3?-O-?-D-galactoside (2). Their structures were determined by UV, IR, HR–ESI–MS, ESI–MS, 1D- and 2D-NMR techniques.

Ming Hua Yang; Jian Guang Luo; Xue Feng Huang; Ling Yi Kong

2010-01-01

154

Two aurone glycosides from heartwood of Pterocarpus santalinus.  

PubMed

Two new aurone glycosides, 6 hydroxy 5 methyl 3',4',5' trimethoxy aurone 4-O-alpha-L-rhamnopyranoside and 6,4' dihydroxy aurone 4-O-rutinoside have been isolated from the ethanolic extract of the wood of Pterocarpus santalinus. Their structures were determined on the basis of chemical and spectroscopic analysis (UV, IR, EIMS, (1)H and (13)C NMR). PMID:15541741

Kesari, Achyut Narayan; Gupta, Rajesh Kumar; Watal, Geeta

2004-12-01

155

New antifungal flavone glycoside from Butea monosperma O. Kuntze.  

PubMed

A new bioactive flavone glycoside was isolated from the methanol soluble fraction of the flowers of Butea monosperma O. Kuntze, which was identified as 5,7-dihydroxy-3,6,4'-trimethoxyflavone-7-O-alpha-L-xylopyranosyl-(1-->3)-O-alpha-L-arabinopyranosyl-(1-->4)-O-beta-D-galactopyranoside (1) by several colour reactions, chemical degradations and spectral analysis. The compound 1 shows antimicrobial activity against various fungal species. PMID:17847718

Yadava, R N; Tiwari, Lata

2007-08-01

156

Quinovic acid glycosides from roots of Macfadyena unguis-cati.  

PubMed

Two glycosides, isolated in good yields from roots of Macfadyena unguis-cati (L.) A. G entry (syn. Doxantha unguis-cati (L.) Miers), gave on hydrolysis the same aglycone (quinovic acid). The sugar moieties have been identified as fucose and glucose respectively. This is the first time that saponins have been found in Bignoniaceae and their occurrence may account of the use of the plant in folk medicine. PMID:17402003

Ferrari, F; Kiyan de Cornelio, I; Delle Monache, F; Marini Bettolo, G B

1981-09-01

157

New phenolic glycosides from the seeds of Cucurbita moschata.  

PubMed

Two new phenolic glycosides were isolated from the seeds of Cucurbita moschata. Their structures were elucidated as (2-hydroxy)phenylcarbinyl 5-O-benzoyl-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (1) and 4-beta-D-(glucopyranosyl hydroxymethyl)phenyl 5-O-benzoyl-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (2) on the basis of spectroscopic analysis and chemical evidence. PMID:20183300

Li, Fa-Sheng; Dou, De-Qiang; Xu, Liang; Chi, Xiao-Feng; Kang, Ting-Guo; Kuang, Hai-Xue

2009-07-01

158

Steroidal glycosides from the aerial part of Asclepias incarnata.  

PubMed

The aerial part of Asclepias incarnata afforded 34 pregnane glycosides. These were confirmed to have lineolon, isolineolon, ikemagenin, 12-O-nicotinoyllineolon, deacylmetaplexigenin, metaplexigenin, rostratamine, 12-O-acetyllineolon, 15beta-hydroxylineolon and 15beta-hydroxyisolineolon moieties as their aglycones, and 2.6-dideoxyhexopyranose, glucopyranose and allopyranose as the corresponding sugar constituents. Their structures were determined using both spectroscopic and chemical methods. PMID:10731028

Warashina, T; Noro, T

2000-02-01

159

Acacetin glycosides as taxonomic markers in Calamintha and Micromeria.  

PubMed

A new acetylated flavone glycoside, acacetin 7-O-[6"-O-acetylglucosyl(1"-->2")]rhamnosyl(1"'-->6")glucoside, has been isolated from the leaves of Calamintha glandulosa together with the known compound acacetin 7-O-rhamnosyl(1"'-->6")glucoside. The occurrence of these flavonoids in the closely related genera Satureja, Micromeria, Acinos and Clinopodium indicates that their distribution may be of taxonomic significance. PMID:11684193

Marin, P D; Grayer, R J; Veitch, N C; Kite, G C; Harborne, J B

2001-11-01

160

Acacetin glycosides as taxonomic markers in Calamintha and Micromeria  

Microsoft Academic Search

A new acetylated flavone glycoside, acacetin 7-O-[6??-O-acetylglucosyl(1???2?)]rhamnosyl(1??6?)glucoside, has been isolated from the leaves of Calamintha glandulosa together with the known compound acacetin 7-O-rhamnosyl(1??6?)glucoside. The occurrence of these flavonoids in the closely related genera Satureja, Micromeria, Acinos and Clinopodium indicates that their distribution may be of taxonomic significance.

Petar D. Marin; Renée J. Grayer; Nigel C. Veitch; Geoffrey C. Kite; Jeffrey B. Harborne

2001-01-01

161

Antioxidative iridoid glycosides and phenolic compounds from Veronica peregrina  

Microsoft Academic Search

Eight iridoid glycosides and four phenolic compounds were isolated from the EtOAc soluble fraction of Veronica peregrina MeOH extract as the radical scavengers for antioxidant activity. The compounds were identified as protocatechuic acid (1), luteolin (2), veronicoside (3), minecoside (4), specioside (5), amphicoside (6), catalposide (7), 6-O-cis-p-coumaroyl catalpol (8), p-hydroxy benzoic acid methyl ester (9), verproside (10), verminoside (11), and

Jong Hwan Kwak; Hyun Jung Kim; Kwang Ho Lee; Se Chan Kang; Ok Pyo Zee

2009-01-01

162

Reverse Logistics.  

National Technical Information Service (NTIS)

The Army has a serious problem with materiel in the supply chain that is moving in the reverse direction. The supply chain is a series of inter- related processes and activities that move supplies and services from the suppliers to the ultimate end users....

J. L. Walden

2001-01-01

163

Glycosidically bound volatiles and flavor precursors in Laurus nobilis L.  

PubMed

Glycosidically bound volatile compounds in different parts (leaves and buds) of Laurus nobilis L. were investigated. After isolation of extracts obtained by Amberlite XAD-2 adsorption and methanol elution, glycosides were analyzed after enzymatic hydrolysis by GC-MS or directly after trifluoroacetyl (TFA) derivatization by GC-MS in EI and NCI mode. In the leaves most of the glycosidically bound volatiles occur as beta-D-glucopyranosides. Among the disaccharides, primeverosides are predominant; smaller amounts of alpha-L-arabinofuranosyl-beta-D-glucopyranosides, rutinosides, and vicianocides could also be identified. Major aglycons comprised benzyl alcohol, some linalool-diols, 2-hydroxy-1,8-cineole and its derivatives such as 2,3-dehydro-1,8-cineole, sobrerols, and menthadien-8-ols. Among the identified nor-carotenoids, 3-oxo-alpha-ionol, the corresponding 7,8-dihydro derivative, and vomifoliol are predominant in leaves. 3-Hydroxy-beta-damascone and 3-hydroxy-7,8-didehydro-beta-ionol, precursors of the sensorially active damascenone, were identified only in the buds. PMID:15769161

Kilic, Ayben; Kollmannsberger, Hubert; Nitz, Siegfried

2005-03-23

164

Minor diterpene glycosides from the leaves of Stevia rebaudiana.  

PubMed

Two new diterpene glycosides in addition to five known glycosides have been isolated from a commercial extract of the leaves of Stevia rebaudiana. Compound 1 (rebaudioside KA) was shown to be 13-[(O-?-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid 2-O-?-d-glucopyranosyl-?-d-glucopyranosyl ester and compound 2, 12-?-[(2-O-?-d-glucopyranosyl-?-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid ?-d-glucopyranosyl ester. Five additional known compounds were identified, rebaudioside E, rebaudioside M, rebaudioside N, rebaudioside O, and stevioside, respectively. Enzymatic hydrolysis of stevioside afforded the known ent-kaurane aglycone 13-hydroxy-ent-kaur-16-en-19-oic acid (steviol) (3). The isolated metabolite 1 possesses the ent-kaurane aglycone steviol (3), while compound 2 represents the first example of the isomeric diterpene 12-?-hydroxy-ent-kaur-16-en-19-oic acid existing as a glycoside in S. rebaudiana. The structures of the isolated metabolites 1 and 2 were determined based on comprehensive 1D- and 2D-NMR (COSY, HSQC, and HMBC) studies. A high-quality crystal of compound 3 has formed, which allowed the acquisition of X-ray diffraction data that confirmed its structure. The structural similarities between the new metabolites and the commercially available stevioside sweeteners suggest the newly isolated metabolites should be examined for their organoleptic properties. Accordingly rebaudiosides E, M, N, O, and KA have been isolated in greater than gram quantities. PMID:24758242

Ibrahim, Mohamed A; Rodenburg, Douglas L; Alves, Kamilla; Fronczek, Frank R; McChesney, James D; Wu, Chongming; Nettles, Brian J; Venkataraman, Sylesh K; Jaksch, Frank

2014-05-23

165

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. PMID:23440017

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

166

A comparison of flavonoid glycosides by electrospray tandem mass spectrometry  

NASA Astrophysics Data System (ADS)

A comparison is presented of product ion mass spectra of protonated and deprotonated molecules of kaempferol-3-O-glucoside, quercitin-3-O-glucoside (isoquercitrin), quercitin-3-O-galactoside (hyperoin), apigenin-7-O-glucoside, luteolin-7-O-glucoside, genistein-7-O-glucoside, naringenin-7-O-glucoside (prunin), luteolin-4'-O-glucoside, luteolin-6-C-glucoside (homoorientin, known also as isoorientin), apigenin-8-C-glucoside (vitexin), and luteolin-8-C-glucoside (orientin) together with the product ion mass spectrum of deprotonated kaempferol-7-O-glucoside. All isomeric ions were distinguishable on the basis of their product ion mass spectra. For protonated 3-O-, 7-O-, and 4'-O-glycosides at a collision energy of 46-47 eV, homolytic cleavage of the O-glycosidic bond yielded aglycon Y+ ions, whereas in deprotonated 3-O-, 7-O-, and 4'-O-glycosides, heterolytic and homolytic cleavage of the O-glycosidic bond yielded radical aglycon (Y-H)- and aglycon (Y-) ions. In each case, fragmentation of either the glycan or the aglycon or both was observed. For 6-C- and 8-C-glycosides at a collision energy of 46-47 eV, fragmentation was restricted almost exclusively to the glycan. For luteolin-6-C-glucoside, the integrity of the aglycon structure is preserved at the expense of the glycan for which some 30 fragmentations were observed. Breakdown curves were determined as a function of collision energy for protonated and deprotonated luteolin-6-C-glucoside. An attempt has been made to rationalize the product ion mass spectra derived from C-O- and C-C-luteolin glucosides in terms of computed structures that indicate significant intramolecular hydrogen bonding and rotation of the B-ring to form a coplanar luteolin structure. It is proposed that protonated and deprotonated luteolin-6-C-glucoside may afford examples of cooperative interactive bonding that plays a major role in directing fragmentation.

March, Raymond E.; Lewars, Errol G.; Stadey, Christopher J.; Miao, Xiu-Sheng; Zhao, Xiaoming; Metcalfe, Chris D.

2006-01-01

167

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 [United States Department of Agriculture (USDA), Western Regional Research Center (WRRC), Albany; Bragg, Jennifer [United States Department of Agriculture (USDA), Western Regional Research Center (WRRC), Albany; Wu, Jiajie [United States Department of Agriculture (USDA), Western Regional Research Center (WRRC), Albany; Yang, Xiaohan [ORNL; Tuskan, Gerald A [ORNL; Vogel, John [United States Department of Agriculture (USDA), Western Regional Research Center (WRRC), Albany

2010-01-01

168

Cardenolide and oxypregnane glycosides from the root of Asclepias incarnata L.  

PubMed

Twenty-nine new oxypregnane glycosides were obtained along with two known cardenolides, frugoside and gofruside, and three known 12-O-acylated pregnane glycosides from the roots of Asclepias incarnata L. (Asclepiadaceae). By detailed studies of the 1H- and 13C-NMR spectra, the structures were determined to be tri- to penta glycosides of isolineolon, 12-O-acetyllineolon, ikemagenin, 12-O-benzoylisolineolon, and two new 12-O-acylated pregnanes. PMID:10783071

Warashina, T; Noro, T

2000-04-01

169

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

170

Proanthocyanidin glycosides and related polyphenols from cacao liquor and their antioxidant effects  

Microsoft Academic Search

Purification of polar fractions from cacao liquor extracts gave 17 phenolics including four new compounds. The new compounds were characterized as a C-glycosidic flavan, an O-glycoside of a dimeric and two O-glycosides of trimeric A-linked proanthocyanidins, on the basis of spectroscopic data. Isolated polyphenols showed inhibitory effects on nicotinamide adenine dinucleotide phosphate-dependent lipid peroxidation in microsomes and on the autoxidation

Tsutomu Hatano; Haruka Miyatake; Midori Natsume; Naomi Osakabe; Toshio Takizawa; Hideyuki Ito; Takashi Yoshida

2002-01-01

171

Novel phenolic glycoside dimer and trimer from the whole herb of Pyrola rotundifolia.  

PubMed

From the water-soluble constituents of the whole herb of Pyrola rotundifolia (Pyrolaceae), one novel phenolic glycoside dimer, pyrolaside A (1), and one novel phenolic glycoside trimer, pyrolaside B (2), together with two known phenolic glycosides homoarbutin (3) and isohomoarbutin (4), were isolated. The structures were elucidated by spectroscopic analysis and confirmed with chemical degradation. In vitro tests for antimicrobial activity showed pyrolaside B (2) to possess significant activity against two Gram-positive organisms, Staphylococcus aureus and Micrococcus luteus. PMID:16079548

Chang, Jun; Inui, Taichi

2005-08-01

172

Herbivore avoidance of digitalis extracts is not mediated by cardiac glycosides.  

PubMed

This study was conducted to determine whether avoidance of digitalis (Digitalis purpurea) by mountain beaver (Aplodontia rufa) is induced by toxic cardiac glycosides. High-performance liquid chromatography and behavioral assays were used to relate animal responses with the presence of common cardiac glycosides in several digitalis extracts. Statistical analyses of multiple-choice tests showed no correlation between cardiac glycoside content and mountain beaver avoidance of apple cubes treated with digitalis extracts. Therefore, we concluded that known toxic cardiac glycosides were not responsible for chemosensory cues that inhibited intake of food treated with digitalis extracts. These results suggest that digitalis is a source of an effective nontoxic herbivore repellent. PMID:24233675

Nolte, D L; Kelly, K L; Kimball, B A; Johnston, J J

1995-10-01

173

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. PMID:23015769

Kalinin, Vladimir I.; Ivanchina, Natalia V.; Krasokhin, Vladimir B.; Makarieva, Tatyana N.; Stonik, Valentin A.

2012-01-01

174

Flavonol glycosides in the petal of Rosa species as chemotaxonomic markers.  

PubMed

Thirteen flavonol glycosides were isolated from the petals of Rosa species belonging to the section Gallicanae, and their structures were identified from their spectroscopic data. These flavonol glycosides, along with two flavonol glycosides isolated from Rosa rugosa, in the petals of 31 Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae were quantitatively analyzed by UPLC. The results indicated that the species belonging to these sections could be classified into four types (Type A, B, C and D) based on the pattern of flavonol glycoside contents, whereas the R. rugosa flavonol glycosides were detected only in section Cinnamomeae. A principal components analysis (PCA) calculated from the 15 flavonol glycosides contained in these samples supported the presence of four types. The distribution of the species in Type D (a group of Cinnamomeae) was shown to reflect close interrelationships, but species in Type B (one group of Gallicanae) could be subdivided into two groups, one of which contained species in section Synstylae. Moreover, the flavonol glycosides were grouped by sugar moieties: a disaccharide composed of two hexoses (S1), a hexose (S2), including a hexose with galloyl group, a pentose (S3), and a disaccharide composed of a hexose and a pentose (S4). The ratios of the amounts of S1-S4 to total flavonol glycoside content indicated that differences among the four sections were more distinctive than the amounts of the 15 flavonol glycosides. The 31 samples were divided into Type B, composed of one type of Gallicanae and Synstylae, Type A+C, composed of another type of Gallicanae and Caninae, and Type D, composed of Cinnamomeae. The R. rugosa flavonol glycosides were shown to be important chemotaxonomic markers for the classification of species in Cinnamomeae, and this method of using flavonol glycosides as chemotaxonomic markers could be useful for the identification of Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae. PMID:25220498

Sarangowa, Ochir; Kanazawa, Tsutomu; Nishizawa, Makoto; Myoda, Takao; Bai, Changxi; Yamagishi, Takashi

2014-11-01

175

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

176

[Effect of plant glycosides on resistance and capacitance vessels].  

PubMed

In the anaesthetized cat, SCOA ( Miroton ), a product which contains extracts from Scilla , Convallaria , Oleander and Adonis , displays not only its well-known positive inotropic effect but has also constrictor effects on veins when applied in intravenous doses of 21.5-100 GPU /kg ( GPU = guinea-pig units, i.e. cardiotoxic equivalents related to 1 g body weight of guinea-pigs). The latter effect differs in that it is somewhat more prolonged. With intraduodenal administration the doses required to achieve equal peak effects as with intravenous injection are about 4 times larger and this suggests a relatively good enteral availability in the cat. SCOA constricts not only veins but also arteries. However, this latter effect is comparatively small and occurs only after intraarterial infusion of high doses (9.1 and 91 GPU /min, respectively).--The cardiac glycosides contained in the drug product primarily account for its vasoactive qualities. The venous constrictor effect correlates with the guinea-pig units. In qualitative respects, the pure glycosides cymarin , convallatoxin , proscillaridin , and scillaren exert equal effects. There is, however, evidence that the correlation between the effect on veins and on the heart differs for the glycosides tested. Based on equal guinea-pig units, the adonis extract, for instance, acts on capacitance vessels about twice as much as scilla , oleander and convallaria extracts. Cymarin , too, has a stronger effect on veins than would be expected from its cardiotoxic effect. The action on arteries and veins are based on different mechanism.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6540100

Lehmann, H D

1984-01-01

177

Two new flavonoid glycosides from Artemisia frigida Willd  

Microsoft Academic Search

An investigation of the n-BuOH-soluble fraction from the aerial parts of Artemisia frigida has led to the isolation of two new flavonoid glycosides, named friginoside A and friginoside B. Their structures were characterized as 5,7-dihydroxy-3?,4?,5?-trimethoxy flavone 7-O-?-d-glucuronide (1) and 5,7-dihydroxy-3?,4?,5?-trimethoxyflavone 7-O-?-d-glucuronyl-(1 ? 2)O-?-d-glucuronide (2) on the basis of 1D and 2D NMR spectral analysis.

Qing-Hu Wang; Wu-Li-Ji Ao; Xiu-Lan Wang; Xiao-Hua Bao; Jin-Hui Wang

2010-01-01

178

Two new flavonoid glycosides from Artemisia frigida Willd.  

PubMed

An investigation of the n-BuOH-soluble fraction from the aerial parts of Artemisia frigida has led to the isolation of two new flavonoid glycosides, named friginoside A and friginoside B. Their structures were characterized as 5,7-dihydroxy-3',4',5'-trimethoxy flavone 7-O-?-d-glucuronide (1) and 5,7-dihydroxy-3',4',5'-trimethoxyflavone 7-O-?-d-glucuronyl-(1 ? 2)O-?-d-glucuronide (2) on the basis of 1D and 2D NMR spectral analysis. PMID:21061216

Wang, Qing-Hu; Ao, Wu-Li-Ji; Wang, Xiu-Lan; Bao, Xiao-Hua; Wang, Jin-Hui

2010-11-01

179

Two new glycosides from the fruits of Morinda citrifolia L.  

PubMed

To study the chemical constituents of the fruits of noni (Morinda citrifolia L.), and find novel compounds, an n-butanol extract of the ethanol soluble fraction was subjected to repeated silica gel and ODS column chromatography and HPLC. Two new glycosides were isolated and their structures elucidated by NMR and HRFAB-MS spectrometry as (2E,4E,7Z)-deca-2,4,7-trienoate-2-O-?-D-glucopyranosyl-?-D-glucopyranoside and amyl-1-O-?-D-apio-furanosyl-1,6-O-?-D-glucopyranoside, respectively. PMID:23103531

Hu, Ming-Xu; Zhang, Hong-Cai; Wang, Yu; Liu, Shu-Min; Liu, Li

2012-01-01

180

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

181

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

182

Pentasaccharide glycosides from the tubers of sweet potato (Ipomoea batatas).  

PubMed

Sweet potato ( Ipomoea batatas) has been used as food and herb in many countries. In this research on the active constituents of sweet potato, nine compounds were isolated and identified, including seven new resin glycosides, batatosides A-G (1- 7), along with two known compounds, batatinoside I ( 8) and simonin IV ( 9). The structures of 1- 9 have been established by a combination of spectroscopic and chemical methods. The major characteristics of the new compounds are the presence of three different substituents. The absolute configuration of aglycones was established as S by Mosher's method. Batatoside E ( 5) showed weak cytotoxic activity against Hep-2 cells. PMID:18341282

Yin, Yongqin; Li, Yi; Kong, Lingyi

2008-04-01

183

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

184

Melitidin: a flavanone glycoside from Citrus grandis 'Tomentosa'.  

PubMed

Citrus grandis 'Tomentosa' is a traditional Chinese medicine, used as an antitussive. In this research, melitidin, a flavanone glycoside, was isolated from this species for the first time by using chromatographic methods. The structure was confirmed through comprehensive analyses of its ultraviolet, infrared, 1H and 13C NMR, HMBC and HMQC spectroscopic and high-resolution mass spectrometric data. Meliditin showed a good antitussive effect on cough induced by citric acid in Guinea pig, suggesting that it was a contributor to the antitussive effect of C. grandis 'Tomentosa'. PMID:23738451

Zou, Wei; Wang, Yonggang; Liu, Haibin; Luo, Yulong; Chen, Si; Su, Weiwei

2013-04-01

185

7-O-Methylated anthocyanidin glycosides from Catharanthus roseus.  

PubMed

Anthocyanins were isolated from orange-red flowers of Catharanthus roseus cv 'Equator Deep Apricot', and identified as rosinidin 3-O-[6-O-(alpha-rhamnopyranosyl)-beta-galactopyranoside] (1), and also 7-O-methylcyanidin 3-O-[6-O-(alpha-rhamnopyranosyl)-beta-galactopyranoside] (2) by chemical and spectroscopic methods. Pigment 1 was found to be a major anthocyanin in the flowers of this cultivar. By contrast, the distribution of rosinidin glycosides is very limited in plants, and reported only in the flowers of Primula. Pigment 2 was found in smaller concentrations, but its aglycone, 7-O-methylcyanidin, has been reported only once before, from the fruit of mango. PMID:18164044

Toki, Kenjiro; Saito, Norio; Irie, Yuki; Tatsuzawa, Fumi; Shigihara, Atsushi; Honda, Toshio

2008-03-01

186

Glycosides from whole plants of Glechoma hederacea L.  

PubMed

From dried whole plants of Glechoma hederacea L. (Labiatae), seven known glycosides were isolated and identified: (6R,7E,9R)-megastigma-4,7-dien-3-one 9-O-beta-D-glucopyranoside (1), apigenin 7-O-neohesperidoside (2), chrysoeriol 7-O-neohesperidoside (3), (+)-pinoresinol 4,4'-bis-O-beta-D-glucopyranoside (4), (+)-syringaresinol 4,4'-bis-O-beta-D-glucopyranoside (5), (+)-lariciresinol 4,4'-bis-O-beta-D-glucopyranoside (6), and (7R,8R)-threo-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan 4-O-beta-D-glucopyranoside (7). PMID:18553179

Kikuchi, Masao; Goto, Junichi; Noguchi, Saori; Kakuda, Rie; Yaoita, Yasunori

2008-10-01

187

Glycosides from whole plants of Glechoma hederacea L  

Microsoft Academic Search

From dried whole plants of Glechoma hederacea L. (Labiatae), seven known glycosides were isolated and identified: (6R,7E,9R)-megastigma-4,7-dien-3-one 9-O-?-d-glucopyranoside (1), apigenin 7-O-neohesperidoside (2), chrysoeriol 7-O-neohesperidoside (3), (+)-pinoresinol 4,4?-bis-O-?-d-glucopyranoside (4), (+)-syringaresinol 4,4?-bis-O-?-d-glucopyranoside (5), (+)-lariciresinol 4,4?-bis-O-?-d-glucopyranoside (6), and (7R,8R)-threo-7,9,9?-trihydroxy-3,3?-dimethoxy-8-O-4?-neolignan 4-O-?-d-glucopyranoside (7).

Masao Kikuchi; Junichi Goto; Saori Noguchi; Rie Kakuda; Yasunori Yaoita

2008-01-01

188

Three new dammarane glycosides from heat processed ginseng  

Microsoft Academic Search

Three new dammarane glycosides were isolated from the processed ginseng (SG; Sun Ginseng). Their structure were determined\\u000a to be 3?,12?-dihydroxydammar-20(21),24-diene-3-O-?-D-glucopyranosyl(1 ? 2)-?-D-glucopyranoside; 3?,12?-dihydroxydammar-20(21),24-diene-3-O-?-D-\\u000a glucopyranoside and 3?,6?,12?-trihydroxydammar-20(21),24-diene-6-O-?-D-glucopyr-anoside based on spectroscopic evidences.\\u000a The compounds were named as ginsenoside Rk1 Rk2, and Rk3 respectively.

II Ho Park; Na Young Kim; Sang Beom Han; Jong Moon Kim; Sung Won Kwon; Hyun Jung Kim; Man Ki Park; Jeong Hill Park

2002-01-01

189

A new steroidal glycoside from the seeds of Hyoscyamus niger.  

PubMed

A new steroidal glycoside hyoscyamoside G (1), together with two known analogues hyoscyamoside E (2) and hyoscyamoside F1 (3), was isolated from the seeds of Hyoscyamus niger. The structure of 1 was established as (22R,24Z)-1?,3?,7?,22,26-pentakishydroxylergost-22-O-?-d-gulcopyranosyl-5,24-diene-26-O-?-d-glucopyranoside, by means of chemical and spectroscopic methods including HRESI-MS, 1D and 2D NMR. In vitro, compound 2 showed cytotoxicity against human lung cancer cell H460 with IC50 value of 66 ?g/mL. PMID:23745717

Zhang, Wenna; Zhang, Wei; Luo, Jianguang; Kong, Lingyi

2013-01-01

190

Synthesis of cardiac glycoside analogs by catalyst-controlled, regioselective glycosylation of digitoxin.  

PubMed

The cardiac glycoside natural product digitoxin was selectively glycosylated at one of its five hydroxyl groups using a borinic acid derived catalyst. This method provided access to the glycosylation pattern characteristic of a subclass of natural products from Digitalis purpurea. Variation of the glycosyl donor was tolerated, enabling the synthesis of novel cardiac glycoside analogs from readily available materials. PMID:23465047

Beale, Thomas M; Taylor, Mark S

2013-03-15

191

Biochemical detoxication: mechanism of differential tiger swallowtail tolerance to phenolic glycosides  

Microsoft Academic Search

Phenolic glycosides, commonly occurring allelochemicals in the plant family Salicaceae, are differentially toxic to subspecies of the eastern tiger swallowtail and responsible for striking differences in the abilities of Papilio glaucus canadensis and P.g. glaucus to utilize the Salicaceae as food plants. This research was designed to test the hypothesis that particularly high esterase activity confers resistance to phenolic glycosides

R. L. Lindroth

1989-01-01

192

The Cyanogenic Glycoside Amygdalin Does Not Deter Consumption of Ripe Fruit by Cedar Waxwings  

Microsoft Academic Search

Cyanogenic glycosides are common secondary compounds in ripe fruits that are dispersed by birds. These substances are toxic to some mammals. We examined the repellent effect of amygdalin, a cyanogenic glycoside, on Cedar Waxwings (Bombycilla cedrorum). Amygdalin did not reduce food ingestion in Cedar Waxwings, even at relatively high concentrations. In addition, these birds did not exhibit preference for amygdalin-free

H. M Struempf; J. E Schondube; Carlos Martinez del Rio

1999-01-01

193

Glycosides of 19-formylthevetiogenin and 5 alpha-thevetiogenin from Thevetia neriifolia.  

PubMed

C-nor-D-homo-homologues of cannogenin and uzarigenin glycosides were isolated along with known cardenolide glycosides from the frozen fresh leaves of Thevetia neriifolia. A bisdesmosidic tetraoside of 3 beta,14,21-trihydroxy-5 beta,14 beta-pregnan-20-one was also obtained from the polar fraction and the structure established. PMID:7765761

Abe, F; Yamauchi, T; Yahara, S; Nohara, T

1994-11-01

194

Antioxidant and cholinesterases inhibitory activities of Verbascum xanthophoeniceum Griseb. and its phenylethanoid glycosides  

Microsoft Academic Search

The members of Verbascum L. (Scrophulariaceae) are known to be rich in phenylethnoid glycosides, and among them Verbascum xanthophoeniceum is an endemic plant species for the Balkan region, Northwestern, and Southern Turkey. A scheme was developed for the isolation of the main active constituents that accumulate in plant aerial parts. The antioxidant activities of total methanol extracts, collected phenylethanoid glycosides

Milen Georgiev; Kalina Alipieva; Ilkay Orhan; Radoslav Abrashev; Petko Denev; Maria Angelova

2011-01-01

195

Selective sequestration of iridoid glycosides from their host plants in Longitarsus flea beetles  

Microsoft Academic Search

We investigated in eight species of the flea beetles genus Longitarsus (Coleoptera, Chrysomelidae) whether the beetles take up iridoid glycosides from their host plants of the Lamiaceae, Plantaginaceae, and Scrophulariaceae. Five of the beetle species, L. australis, L. lewisii, L. melanocephalus, L. nigrofasciatus, and L. tabidus, could be shown to sequester iridoid glycosides in concentrations between 0.40 and 1.55% of

Gunther Willinger; Susanne Dobler

2001-01-01

196

A new flavonol glycoside from the aerial part of Rudbeckia laciniata.  

PubMed

The phytochemical investigation of Rudbeckia laciniata L. obtained a new flavonol glycoside (1), together with four flavonol glycosides (2-5) and eight quinic acid derivatives (6-13). The structure was elucidation by means of spectroscopic methods and chemical evidence. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using the sulforhodamine B bioassay. PMID:24062080

Lee, Seung Young; Shin, Young June; Choi, Sang Un; Lee, Kang Ro

2014-07-01

197

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

198

Phenylethanoid glycosides from the stems of Callicarpa peii (hemostatic drug).  

PubMed

Two new trisaccharide intermediates of phenylethanoid glycosides, peiioside A(1)/A(2) (1a/1b) and peiioside B (2), were isolated from the n-BuOH fraction of MeOH extract of the stems of Callicarpa peii H.T. Chang, together with five biogenetic relevant known compounds 3-7. The structures of compounds 1 and 2 were elucidated by extensive spectroscopic methods (especially 2D-NMR techniques) and acid-catalyzed hydrolysis as O-?-l-rhamnopyranosyl-(1??3')-O-[?-d-apiofuranosyl-(1??6')] -4'-O-[(E)-caffeoyl]-d-glucopyranoside] (1a/1b), 3,4-dihydroxy-?-phenylethoxy-O-[?-d-apiofuranosyl-(1??6')-?-l-rhamnopyranosyl-(1??3')-O-?-d-glucopyranoside] (2), respectively. On the basis of the isolated compounds, a presumable biogenetic pathway of the biologically interesting phenylethanoid glycosides about forsythoside B (3) and acteoside (4) isolated from this species was proposed. Isolation of five related intermediates (1-2, 5-7) provided further support for the biogenetic path. This is the first report about phytochemical research on C. peii and the biogenetic hypothesis of forsythoside B and acteoside. PMID:23262269

Wu, Ai-Zhi; Zhai, Ya-Jing; Zhao, Zhong-Xiang; Zhang, Cui-Xian; Lin, Chao-Zhan; Zhu, Chen-Chen

2013-01-01

199

Separation of phenylpropanoid glycosides from a Chinese herb by HSCCC.  

PubMed

An effective high-speed counter-current chromatography method was established for the preparative isolation and purification of two phenylpropanoid glycosides from the Tibetan medicinal plant Pedicularis longiflora Rudolph. var. tubiformis (Klotz). Tsoong. With a two-phase solvent system composed of chloroform-n-butanol-methanol-water (4:3:4:5, v/v), 40 mg of an extract of Pedicularis longiflora Rudolph. var. tubiformis (Klotz). Tsoong was separated to yield 20 mg of verbascoside and 18 mg of isoacteoside, with purity values of 97 and 98%, respectively. The chemical structures of these two components were identified by proton and carbon nuclear magnetic resonance. In addition, the antioxidant activity of the two phenylpropanoid glycosides was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH)-high-performance liquid chromatography, and the results showed that the two components exhibited strong antioxidant DPPH radical scavenging activity, with IC50 values of 15.6 and 18.9 µg/mL, respectively. PMID:23680899

Chen, Chen; Zhao, Xiao-Hui; Yue, Hui-Lan; Li, Yu-Lin; Chen, Tao

2014-01-01

200

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. PMID:24970171

Trincone, Antonio

2013-01-01

201

Potent antiviral flavone glycosides from Ficus benjamina leaves.  

PubMed

Crude ethanol extracts from Ficus benjamina leaves strongly inhibit Herpes Simplex Virus 1 and 2 (HSV-1/2) as well as Varicella Zoster Virus (VZV) cell infection in vitro. Bioassay-guided fractionation of the crude extract demonstrated that the most efficient inhibition of HSV-1 and HSV-2 was obtained with the flavonoid fraction. The present study was aimed to further isolate, purify and identify substances with potent antiviral activity from the flavonoid fraction of F. benjamina extracts. Flavonoids were collected from the leaf ethanol extracts through repeated purification procedure and HPLC analysis. The antiviral activity of each substance was then evaluated in cell culture. Three known flavone glycosides, (1) quercetin 3-O-rutinoside, (2) kaempferol 3-O-rutinoside and (3) kaempferol 3-O-robinobioside, showing highest antiviral efficiency were selected and their structure was determined by spectroscopic analyses including NMR and mass spectrometry (MS). These three flavones were highly effective against HSV-1 reaching a selectivity index (SI) of 266, 100 and 666 for compound 1, 2 and 3, respectively, while the SI of their aglycons, quercetin and kaempferol amounted only in 7.1 and 3.2, respectively. Kaempferol 3-O-robinobioside showed similar SI to that of acyclovir (ACV), the standard anti-HSV drug. Although highly effective against HSV-1 and HSV-2, these flavone glycosides did not show any significant activity against VZV. PMID:22155188

Yarmolinsky, Ludmila; Huleihel, Mahmoud; Zaccai, Michele; Ben-Shabat, Shimon

2012-03-01

202

Flacourtosides A-F, phenolic glycosides isolated from Flacourtia ramontchi.  

PubMed

In an effort to identify novel inhibitors of chikungunya (CHIKV) and dengue (DENV) virus replication, a systematic study with 820 ethyl acetate extracts of madagascan plants was performed in a virus-cell-based assay for CHIKV, and a DENV NS5 RNA-dependent RNA polymerase (RdRp) assay. The extract obtained from the stem bark of Flacourtia ramontchi was selected for its significant activity in both assays. Six new phenolic glycosides, named flacourtosides A-F (1-6), phenolic glycosides itoside H, xylosmin, scolochinenoside D, and poliothrysoside, and betulinic acid 3?-caffeate were obtained using the bioassay-guided isolation process. Their structures were elucidated by comprehensive analyses of NMR spectroscopic and mass spectrometric data. Even though several extracts and fractions showed significant selective antiviral activity in the CHIKV virus-cell-based assay, none of the purified compounds did. However, in the DENV RNA polymerase assay, significant inhibition was observed with betulinic acid 3?-caffeate (IC(50) = 0.85 ± 0.1 ?M) and to a lesser extent for the flacourtosides A and E (1 and 5, respectively), and scolochinenoside D (IC(50) values ~10 ?M). PMID:22439591

Bourjot, Mélanie; Leyssen, Pieter; Eydoux, Cécilia; Guillemot, Jean-Claude; Canard, Bruno; Rasoanaivo, Philippe; Guéritte, Françoise; Litaudon, Marc

2012-04-27

203

Agrobacterium Mediated Transient Gene Silencing (AMTS) in Stevia rebaudiana: Insights into Steviol Glycoside Biosynthesis Pathway  

PubMed Central

Background Steviol glycoside biosynthesis pathway has emerged as bifurcation from ent-kaurenoic acid, substrate of methyl erythritol phosphate pathway that also leads to gibberellin biosynthesis. However, the genetic regulation of steviol glycoside biosynthesis has not been studied. So, in present study RNA interference (RNAi) based Agrobacterium mediated transient gene silencing (AMTS) approach was followed. SrKA13H and three SrUGTs (SrUGT85C2, SrUGT74G1 and SrUGT76G1) genes encoding ent-kaurenoic acid-13 hydroxylase and three UDP glycosyltransferases of steviol glycoside biosynthesis pathway were silenced in Stevia rebaudiana to understand its molecular mechanism and association with gibberellins. Methodology/Principal Findings RNAi mediated AMTS of SrKA13H and three SrUGTs has significantly reduced the expression of targeted endogenous genes as well as total steviol glycoside accumulation. While gibberellins (GA3) content was significantly enhanced on AMTS of SrUGT85C2 and SrKA13H. Silencing of SrKA13H and SrUGT85C2 was found to block the metabolite flux of steviol glycoside pathway and shifted it towards GA3 biosynthesis. Further, molecular docking of three SrUGT proteins has documented highest affinity of SrUGT76G1 for the substrates of alternate pathways synthesizing steviol glycosides. This could be a plausible reason for maximum reduction in steviol glycoside content on silencing of SrUGT76G1 than other genes. Conclusions SrKA13H and SrUGT85C2 were identified as regulatory genes influencing carbon flux between steviol glycoside and gibberellin biosynthesis. This study has also documented the existence of alternate steviol glycoside biosynthesis route. PMID:24023961

Guleria, Praveen; Yadav, Sudesh Kumar

2013-01-01

204

Enzymatic hydrolysis of steryl glycosides for their analysis in foods.  

PubMed

Steryl glycosides (SG) contribute significantly to the total intake of phytosterols. The standard analytical procedure involving acid hydrolysis fails to reflect the correct sterol profile of SG due to isomerization of some of the labile sterols. Therefore, various glycosylases were evaluated for their ability to hydrolyse SG under milder conditions. Using a pure SG mixture in aqueous solution, the highest glycolytic activity, as demonstrated by the decrease in SG and increase in free sterols was achieved using inulinase preparations (decrease of >95%). High glycolytic activity was also demonstrated using hemicellulase (63%). The applicability of enzymatic hydrolysis using inulinase preparations was further verified on SG extracted from foods. For example in potato peel ?(5)-avenasteryl glucoside, a labile SG, was well preserved and contributed 26.9% of the total SG. Therefore, enzymatic hydrolysis is suitable for replacing acid hydrolysis of SG in food lipid extracts to accurately determine the sterol profile of SG. PMID:24912717

Münger, Linda H; Nyström, Laura

2014-11-15

205

Sesquiterpene lactone glycosides from Lapsana communis L. subsp. communis  

Microsoft Academic Search

From the latex of Lapsana communis L. subps. communis, five guaianolide glycosides were identified: crepiside E, tectoroside and three new ones: 3-O-P-d-glucopyranosyl-8-O-P-acetyl-1aH,5aH,6PH,7aH-guai-4 (15),10 (14),11 (13)-triene-6,12-olide, 3-O-P-d-glucopyranosyl-8-O-P-acetyl-1aH,5aH,6PH,7aH-guai-3 (4),10 (14), 11 (13)-triene-15-methyl-6,12-olide, and 3-O-P-glucopyranosyl-8-O-P- (4-hydroxyphenyl)-lactyl-1aH,5aH,6PH,7aH-guai-3 (4),10 (14),11 (13)-triene-15-methyl-6,12-olide. Their structures were established by spectroscopic methods.

Didier Fontanel; Christophe Galtier; Jean-Claude Debouzy; Alain Gueiffier; Claude Viel

1999-01-01

206

Sesquiterpene lactone glycosides from Lapsana communis L. subsp. communis.  

PubMed

From the latex of Lapsana communis L. subps. communis, five guaianolide glycosides were identified: crepiside E, tectoroside and three new ones: 3-O-beta-D-glucopyranosyl-8-O-beta-acetyl-1 alpha H,5 alpha H,6 beta H,7 alpha H-guai-4(15),10(14),11(13)-triene-6,12-olide, 3-O-beta-D-glucopyranosyl-8-O-beta-acetyl-1 alpha H,5 alpha H,6 beta H,7 alpha H-guai-3(4),10(14), 11(13)-triene-15-methyl-6,12-olide, and 3-O-beta-glucopyranosyl-8-O-beta-(4-hydroxyphenyl)-lactyl-1 alpha H,5 alpha H,6 beta H,7 alpha H-guai-3(4),10(14),11(13)-triene-15-methyl-6,12-olide. Their structures were established by spectroscopic methods. PMID:10444857

Fontanel, D; Galtier, C; Debouzy, J C; Gueiffier, A; Viel, C

1999-08-01

207

Acylated flavonol glycosides from leaves of Stenochlaena palustris.  

PubMed

From the leaves of Stenochlaena palustris five new O-acylated flavonol glycosides, stenopalustrosides A-E (1-5), have been isolated along with five known compounds, kaempferol 3-O-(3' '-O-E-p-coumaroyl)-(6' '-O-E-feruloyl)-beta-D-glucopyranoside (6), kaempferol 3-O-(3' ',6' '-di-O-E-p-coumaroyl)-beta-D-glucopyranoside (7), kaempferol 3-O-(3' '-O-E-p-coumaroyl)-beta-D-glucopyranoside (8), kaempferol 3-O-(6' '-O-E-p-coumaroyl)-beta-D-glucopyranoside (9); and kaempferol 3-O-beta-D-glucopyranoside (10). The structures of the isolates were elucidated by spectroscopic methods, mainly 1D and 2D NMR. Compounds 1-4 showed significant antibacterial activities against Gram-positive strains. The structural difference between the isolated antibacterial and nonantibacterial compounds is discussed. PMID:9917285

Liu, H; Orjala, J; Sticher, O; Rali, T

1999-01-01

208

Flavonoid glycosides and pharmacological activity of Amphilophium paniculatum  

PubMed Central

Background: Nothing is reported on Amphilophium paniculatum (L.) Kunth. This study aimed at investigation of chemical constituents of the leaves of Amphilophium paniculatum, grown in Egypt, in addition to pharmacological evaluation. Materials and Methods: Isolation of a new compound, along with 5 known flavonoids. Pharmacological activities were carried out on different extracts of A. paniculatum leaves. Results: Identification of a new flavone glycoside, acacetin 8-C-?-D- glucopyranosy l-(1?2)-?-L-rhamnopyranoside (1) in addition to 5 known flavonoids. The 70% ethanol crud extract and its successive chloroform, ethyl acetate, and 100% ethanol extracts showed significant anti-inflammatoryactivity,analgesic effect, antipyretic activity, antioxidant activity, and anti-hyperglycemic activity. Determination of the median lethal dose (LD50) revealed that the different extracts were safe. PMID:23598920

Nassar, Mahmoud I.; Aboutabl, El-Sayed A.; Eskander, Dina M.; Grace, Mary H.; EL-Khrisy, Ezzel-Din A.; Sleem, Amany A.

2013-01-01

209

Tigliane-type diterpenoid glycosides from Euphorbia fischeriana.  

PubMed

Investigation of whole plants of Euphorbia fischeriana afforded three new tigliane-diterpenoid glycosides, fischerosides A-C (1-3), together with 11 known diterpenoids. Fischerosides A-C (1-3) are the first tigliane-type diterpenoid glucosides. Their structures were determined by a combination of 1D and 2D NMR, MS, and acid hydrolysis. Inhibitory activity against HIV-1 was assessed for compounds 1-5. The new compound 3 showed an EC?? value of 0.02 ?M and a therapeutic index (TI) of 17.50, while prostratin (4) and 12-deoxyphorbol-13,20-diacetate (5) showed significantly greater anti-HIV-1 activity. PMID:21534540

Pan, Li-Li; Fang, Ping-Lei; Zhang, Xing-Jie; Ni, Wei; Li, Lei; Yang, Liu-Meng; Chen, Chang-Xiang; Zheng, Yong-Tang; Li, Chang-Tian; Hao, Xiao-Jiang; Liu, Hai-Yang

2011-06-24

210

Flavonoid Glycosides from the Seeds of Litchi chinensis.  

PubMed

Seven flavonoid glycosides, including one new (1) and five previously uncharacterized (3-7), were obtained from the seeds of lychee ( Litchi chinensis Sonn. cv. Heiye) by means of repetitive column chromatography and high-performance liquid chromatography (HPLC) preparation. They were identified as litchioside D (1), (-)-pinocembrin 7-O-neohesperidoside (2), (-)-pinocembrin 7-O-rutinoside (3), taxifolin 4'-O-?-d-glucopyranoside (4), kaempferol 7-O-neohesperidoside (5), tamarixetin 3-O-rutinoside (6), and phlorizin (7) on the basis of spectroscopic analysis and comparison of their data to the values reported in the literatures. Among them, compounds 1, 4, and 5 showed in vitro antitumor activity against A549, LAC, Hep-G2, and HeLa cell lines in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. PMID:21287989

Xu, Xinya; Xie, Haihui; Hao, Jing; Jiang, Yueming; Wei, Xiaoyi

2011-02-23

211

New spirostanol glycosides from Solanum nigrum and S. jasminoides.  

PubMed

A new characteristic steroidal glycoside possessing a hydroxyl group at C-23, inunigroside A (1), was isolated from the withered berries of Solanum nigrum L. On the basis of spectroscopic analysis, the structure of 1 was characterized as (5?,22S,23S,25R)-3?,23-dihydroxyspirostane 3-O-?-lycotetraoside. Next, a major steroidal sapogenol, (22R, 25S)-3?,15?-dihydroxy-spirost-5-ene (3), was obtained from the acid hydrolysate of the methanolic extract of the aerial parts of Solanum jasminoides L. A new bisdesmoside, 3-O-?-D-glucopyranosyl-(1?4)-?-D-glucopyranosyl-(1?4)-?-D-glucopyranosyl (22R,25S)-3?,15?-dihydroxyspirost-5-ene 15-O-?-L-rhamnopyranoside (4), named jasminoside A, was isolated from the methanolic extract of S. jasminoides. PMID:22388971

Ohno, Mizuho; Murakami, Kotaro; El-Aasr, Mona; Zhou, Jian-Rong; Yokomizo, Kazumi; Ono, Masateru; Nohara, Toshihiro

2012-10-01

212

Additional minor diterpene glycosides from Stevia rebaudiana Bertoni.  

PubMed

Two additional novel minor diterpene glycosides were isolated from the commercial extract of the leaves of Stevia rebaudiana Bertoni. The structures of the new compounds were identified as 13-{?-D-glucopyranosyl-(1 ? 2)-O-[?-D-glucopyranosyl-(1 ? 3)-?-D-glucopyranosyl-oxy} ent-kaur-16-en-19-oic acid {?-D-xylopyranosyl-(1 ? 2)-O-[?-D-glucopyranosyl-(1 ? 3)]-O-?-D-glucupyranosyl-ester} (1), and 13-{?-D-6-deoxy-glucopyranosyl-(1 ? 2)-O-[?-D-glucopyranosyl-(1 ? 3)-?-D-glucopyranosyl-oxy} ent-kaur-16-en-19-oic acid {?-D-glucopyranosyl-(1 ? 2)-O-[?-D-glucopyranosyl-(1 ? 3)-?-D-gluco-pyranosyl-ester} (2), on the basis of extensive 1D (1H- and 13C-) 2D NMR (COSY, HSQC and HMBC) and MS spectroscopic data as well as chemical studies. PMID:24184820

Prakash, Indra; Chaturvedula, Venkata Sai Prakash

2013-01-01

213

Absorption, metabolism and elimination of strophanthus glycosides in man.  

PubMed

In 33 healthy male volunteers, given a single oral and intravenous dose of cymarin (k-strophanthin-alpha), k-strophanthoside (k-strophanthin-gamma) and ouabain (g-strophanthin), enteral absorption and renal excretion of these glycosides and their metabolites were investigated by radioimmunoassay and HPLC. Cymarin was absorbed at 47% of the given dose. After intravenous injection 46% and after oral administration 21% of the given dose, i.e. the total amount as detected by radioimmunoassay which consisted of the unchanged glycoside and its metabolites, were excreted by the kidneys mainly as conjugated metabolites. The half-life of elimination, calculated from the total excreted amount was 13 h (i.v.) and 23 h (p.o.), respectively. k-Strophanthoside was absorbed at 16% of the given dose. After i.v.-injection 73% of the given dose was excreted by the kidneys with a half-life of elimination of 99 h. From this total amount about 70% was excreted as the unchanged drug, the remaining 30% as various metabolites. After oral administration 11% of the given dose were excreted with a half-life of elimination of 22 h. 80% of this amount consisted mainly of conjugated k-strophanthoside and conjugated metabolites as k-strophanthin-beta, cymarin, k-strophanthidin, cymarol and k-strophanthidol. Only 6% was excreted as the unchanged drug. Ouabain was absorbed after oral administration to a minimum of 1.4%. Given intravenously a total renal excretion of 33% of the given dose with a half-life of elimination of 23 h was measured. Of this 80% was unchanged ouabain.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3821940

Strobach, H; Wirth, K E; Rojsathaporn, K

1986-12-01

214

Characterization of an anti-tuberculosis resin glycoside from the prairie medicinal plant Ipomoea leptophylla.  

PubMed

The organic soluble extract from the leaves of the native North American prairie plant Ipomoea leptophylla (big root morning glory) showed in vitro activity against M. tuberculosis. Bioassay-guided fractionation of this extract resulted in the identification of two new resin glycosides (6, 7). Base-catalyzed hydrolysis of these glycosides gave operculinic acid (1) as the glycosidic acid component as well as trans-cinnamic acid, propanoic acid, and lauric acid. The complete structure elucidation was accomplished through derivatization, 1D and 2D NMR spectroscopy (TOCSY, ROESY, HSQC, HMBC), and MS/MS experiments on 6 and 7 as well as the permethylated derivative 8. PMID:14640518

Barnes, Curtis C; Smalley, Mary K; Manfredi, Kirk P; Kindscher, Kelly; Loring, Hillary; Sheeley, Douglas M

2003-11-01

215

One-pot chemo-, regio-, and stereoselective double-differential glycosidation mediated by lanthanide triflates.  

PubMed

Nuanced activation of n-pentenyl, thioglycoside, and trichloroacetimidate donors by lanthanide salts coupled with donor/acceptor matching can simplify oligosaccharide assembly. Thus, a one-pot, double-differential glycosidation process can be designed, in which an n-pentenyl acceptor-diol is chemo- and regioselectively glycosidated by using an n-pentenyl ortho ester under the agency of Yb(OTf)(3)/NIS followed by in situ addition of a 2-O-acylated trichloroacetimidate or ethyl thioglycoside to effect stereoselective glycosidation at the remaining OH. PMID:15524445

Jayaprakash, K N; Fraser-Reid, Bert

2004-11-11

216

Reversible phosphorylation in mitochondria.  

E-print Network

??Mitochondria represent an underappreciated site of regulation by reversible phosphorylation. Our work has focused on the identification of proteins involved in regulating mitochondria by reversible… (more)

Rardin, Matthew James

2008-01-01

217

Ultra-sonication-assisted solvent extraction of quercetin glycosides from 'Idared' apple peels.  

PubMed

Quercetin and quercetin glycosides are physiologically active flavonol molecules that have been attributed numerous health benefits. Recovery of such molecules from plant matrices depends on a variety of factors including polarity of the extraction solvent. Among the solvents of a wide range of dielectric constants, methanol recovered the most quercetin and its glycosides from dehydrated 'Idared' apple peels. When ultra-sonication was employed to facilitate the extraction, exposure of 15 min of ultrasound wavelengths of dehydrated apple peel powder in 80% to 100% (v/v) methanol in 1:50 (w:v) solid to solvent ratio provided the optimum extraction conditions for quercetin and its glycosides. Acidification of extraction solvent with 0.1% (v/v) or higher concentrations of HCl led to hydrolysis of naturally occurring quercetin glycosides into the aglycone as an extraction artifact. PMID:22117169

Vasantha Rupasinghe, H P; Kathirvel, Priya; Huber, Gwendolyn M

2011-01-01

218

Fast atom bombardment and tandem mass spectrometry for structure determination of steroid and flavonoid glycosides.  

PubMed

The combination of fast atom bombardment (FAB) and tandem mass spectrometry (MS-MS) was tested for its applicability to generate useful structural information for steroid and flavonoid glycosides. The following compounds were investigated: quercetin, myricitrin, apigetrin, fraxin, rutin, neohesperidin, hesperidin, naringin, apiin, cymarin, digoxin, digitoxin, xanthorhamnin, and frangulin. Upon FAB, the sample molecules are desorbed as (M + H)+, (M - H)-, or as (M + Na)+ or (M + K)+. Collisional activation of (M + H)+ or (M - H)- ions in the MS-MS experiment leads to sequential losses of glycoside moieties in a manner which permits the sequence of glycosides to be established. Some glycosides occur as mixtures of homologs. Proper interpretation of the MS-MS or collisional activation decomposition spectra often allows the homology to be located. In addition to the simple and highly selective fragmentations observed in this combined experiment, FAB and MS-MS also remove interference caused by the ubiquitous matrix ions which are desorbed by FAB. PMID:3728980

Crow, F W; Tomer, K B; Looker, J H; Gross, M L

1986-06-01

219

High-throughput cloning, expression and purification of glycoside hydrolases using Ligation-Independent Cloning (LIC).  

PubMed

Recent advances in DNA sequencing techniques have led to an explosion in the amount of available genome sequencing data and this provided an inexhaustible source of uncharacterized glycoside hydrolases (GH) to be studied both structurally and enzymatically. Ligation-Independent Cloning (LIC), an interesting alternative to traditional, restriction enzyme-based cloning, and commercial recombinatorial cloning, was adopted and optimized successfully for a high throughput cloning, expression and purification pipeline. Using this platform, 130 genes encoding mainly uncharacterized glycoside hydrolases from 13 different organisms were cloned and submitted to a semi-automated protein expression and solubility screening in Escherichia coli, resulting in 73 soluble targets. The high throughput approach proved to be a powerful tool for production of recombinant glycoside hydrolases for further structural and biochemical characterization and confirmed that thioredoxin fusion tag (TRX) is a better choice to increase solubility of recombinant glycoside hydrolases expressed in E. coli, when compared to His-tag alone. PMID:24680731

Camilo, Cesar M; Polikarpov, Igor

2014-07-01

220

A new phenolic glycoside and a new trans-clerodane diterpene from Conyza blinii.  

PubMed

A new phenolic glycoside, 4-propionyl-2,6-dimethoxyphenyl beta-D-glucopyranoside (1) and a new trans-clerodane diterpene named 19-deacetylconyzalactone (2), were isolated from the aerial parts of Conyza blinii. PMID:11491399

Su, Y F; Guo, D A; Cui, Y J; Liu, J S; Zheng, J H

2001-01-01

221

Solubility Enhancement of Steviol Glycosides and Characterization of Their Inclusion Complexes with Gamma-Cyclodextrin  

PubMed Central

Steviol glycosidesrebaudioside (reb) A, C and D have low aqueous solubilities. To improve their aqueous solubilities, inclusion complex of steviol glycosides, reb A, C and D and gamma cyclodextrin were prepared by freeze drying method and further characterized by means of differential scanning calorimetry, Fourier transform infrared spectroscopy and Raman spectroscopy. The effect of gamma cyclodextrin on chemical shifts of the steviol glycosides was also studied in proton NMR experiments as well as in solid state 13C CP/MAS NMR experiments. These results indicated that the steviol glycosides were clearly in inclusion complex formation with the gamma cyclodextrin which also results in solubility enhancement of these steviol glycosides. Phase solubility studies showed that amounts of soluble reb A, C and D increased with increasing amounts of gamma cyclodextrin indicating formation of 1:1 stoichiometric and higher order inclusion complexes. PMID:22174615

Upreti, Mani; Strassburger, Ken; Chen, You L.; Wu, Shaoxiong; Prakash, Indra

2011-01-01

222

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. PMID:21807619

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

2011-01-01

223

Processivity and Enzymatic Mode of a Glycoside Hydrolase Family 5 Endoglucanase from Volvariella volvacea  

PubMed Central

EG1 is a modular glycoside hydrolase family 5 endoglucanase from Volvariella volvacea consisting of an N-terminal carbohydrate-binding module (CBM1) and a catalytic domain (CD). The ratios of soluble to insoluble reducing sugar produced from filter paper after 8 and 24 h of exposure to EG1 were 6.66 and 8.56, respectively, suggesting that it is a processive endoglucanase. Three derivatives of EG1 containing a core domain only or additional CBMs were constructed in order to evaluate the contribution of the CBM to the processivity and enzymatic mode of EG1 under stationary and agitated conditions. All four enzymatic forms exhibited the same mode of action on both soluble and insoluble cellulosic substrates with cellobiose as a main end product. An additional CBM fused at either the N or C terminus reduced specific activity toward soluble and insoluble celluloses under stationary reaction conditions. Deletion of the CBM significantly decreased enzyme processivity. Insertion of an additional CBM also resulted in a dramatic decrease in processivity in enzyme-substrate reaction mixtures incubated for 0.5 h, but this effect was reversed when reactions were allowed to proceed for longer periods (24 h). Further significant differences were observed in the substrate adsorption/desorption patterns of EG1 and enzyme derivatives equipped with an additional CBM under agitated reaction conditions. An additional family 1 CBM improved EG1 processivity on insoluble cellulose under highly agitated conditions. Our data indicate a strong link between high adsorption levels and low desorption levels in the processivity of EG1 and possibly other processive endoglucanses. PMID:23204424

Zheng, Fei

2013-01-01

224

A new flavonoid glycoside from the rhizomes and roots of Smilax scobinicaulis.  

PubMed

A new flavonoid glycoside, hesperetin-7-O-[?-D-glucopyranosyl-(1 ? 3)]-?-D-glucopyranosyl (1), was isolated from the n-BuOH extract of Smilax scobinicaulis, together with four known flavonoid glycosides, clematine (2), ononin (3), daidzin (4) and puerarin (5). All of the five compounds were reported from this material for the first time. Their structures were determined on the basis of spectroscopic and spectrometric methods. PMID:24483603

Xu, Jing; Feng, Shixiu; Wang, Qi; Zhang, Min; Zhang, Cunli

2014-01-01

225

Cardiac Glycosides Induce Cell Death in Human Cells by Inhibiting General Protein Synthesis  

Microsoft Academic Search

BackgroundCardiac glycosides are Na+\\/K+-pump inhibitors widely used to treat heart failure. They are also highly cytotoxic, and studies have suggested specific anti-tumor activity leading to current clinical trials in cancer patients. However, a definitive demonstration of this putative anti-cancer activity and the underlying molecular mechanism has remained elusive.Methodology\\/Principal FindingsUsing an unbiased transcriptomics approach, we found that cardiac glycosides inhibit general

Andrea Perne; Markus K. Muellner; Magdalena Steinrueck; Nils Craig-Mueller; Julia Mayerhofer; Ilse Schwarzinger; Mathew Sloane; Iris Z. Uras; Gregor Hoermann; Sebastian M. B. Nijman; Matthias Mayerhofer; Alfred Lewin

2009-01-01

226

Glycosidation of thioglycosides in the presence of bromine: mechanism, reactivity, and stereoselectivity.  

PubMed

Elaborating on previous studies by Lemieux for highly reactive "armed" bromides, we discovered that ?-bromide of the superdisarmed (2-O-benzyl-3,4,6-tri-O-benzoyl) series can be directly obtained from the thioglycoside precursor. When this bromide is glycosidated, ?-glycosides form exclusively; however, the yields of such transformations may be low due to the competing anomerization into ?-bromide that is totally unreactive under the established reaction conditions. PMID:22136383

Kaeothip, Sophon; Yasomanee, Jagodige P; Demchenko, Alexei V

2012-01-01

227

Fate of iridoid glycosides in different life stages of the Buckeye, Junonia coenia (Lepidoptera: Nymphalidae)  

Microsoft Academic Search

The buckeye butterfly,Junonia coenia (Lepidoptera: Nymphalidae), specializes on plants that contain iridoid glycosides. To determine the fate of these compounds in larvae, pupae, and adults of this species, we reared larvae on artificial diets with and without iridoid glycosides, and on leaves of a host plant,Plantago lanceolata (Plantaginaceae). Quantification by gas chromatography showed that newly molted third-, fourth-, and fifth-instar

M. Deane Bowers; Sharon K. Collinge

1992-01-01

228

Occurrence of iridoid glycosides in in vitro cultures and intact plants of Scrophularia nodosa L  

Microsoft Academic Search

Shoot, root, and callus cultures of Scrophularia nodosa L. (Scrophulariaceae) were established and cultivated in vitro. Iridoid glycosides, such as harpagoside, aucubin, and catalpol\\u000a were identified by LC-ESI-MS and their contents determined by HPLC. For comparison intact plants of S. nodosa were analysed. In shoot cultures slightly lower amounts of detectable iridoid glycosides (4.36% dry weight) were determined\\u000a than in

Katja Sesterhenn; Melanie Distl; Michael Wink

2007-01-01

229

Steroidal glycosides from the aerial part of Asclepias incarnata L. II.  

PubMed

Thirty new steroidal glycosides were obtained from the aerial part of Asclepias incarnata L. (Asclepiadaceae). These glycosides were confirmed to have lineolon, isolineolon, 12-O-acetyllineolon, 12-O-(Z)-cinnamoyllineolon, metaplexigenin, 15 beta-hydroxylineolon, 15 beta-hydroxyisolineolon, 16 alpha-hydroxyisolineolon, 12-O-tigloyl-16 alpha-hydroxyisolineolon as the aglycone and 2,6-dideoxyhexopyranose as the sugar sequence by spectroscopic methods and chemical evidence. PMID:10705484

Warashina, T; Noro, T

2000-01-01

230

Acetophenones and new pregnane glycosides from the roots of Vincetoxicum hirundinaria  

Microsoft Academic Search

The roots of Vincetoxicum hirundinaria yielded the known pregnane glycosides cynatratoside E and cynatratoside C and three new pregane glycosides: hirundicoside B, hirundicoside C and hirundicoside D. Their structures have been elucidated by spectral data. Other isolated constituents: 2-hydroxyacetophenone, paenol, apocynine, 4-hydroxyacetophenone, 2,4-dihydroxyacetophenone, hancolupenone, sitosterol and syringic acid. 2-Hydroxyacetophenone was also identified as the major constituent of the essential oil

M Lavault; P Richomme; J Bruneton

1999-01-01

231

Determination of Iridoid Glycosides from Four Turkish Lamium Species by HPLC-ESI\\/MS  

Microsoft Academic Search

An HPLC-ESI\\/MS method that enables fast detection and identification of iridoid glycosides is described. Eleven iridoid glycosides known to occur in the genus Lamium -lamalbide, sesamoside, 6- ?-OH ipolamiide, shanzhiside methyl ester, dehydropenstemoside, barlerin (= 8-O-acetylshanzhiside methyl ester), 6-O-syringyl-8-O-acetylshanzhiside methyl ester, lamerioside, lamiide, eriobioside, and ipolamiide, were identified by means of their retention time and ESI\\/MS data. This method was

Turk J Chem; Erhan PALASKA

232

Iridoid glycosides isolated from Scrophularia dentata Royle ex Benth. and their anti-inflammatory activity.  

PubMed

Scrodentosides A-E (1-5), five new acylated iridoid glycosides, together with 19 known ones, were isolated from the whole plant of Scrophularia dentata Royle ex Benth. The structures of these isolated glycosides were elucidated by spectroscopic methods. Bioassay showed that compounds 7 and 11 had significant inhibitory effect against NF-?B activation with IC50 value of 43.7?M and 1.02?M respectively. PMID:25016952

Zhang, Liuqiang; Zhu, Tiantian; Qian, Fei; Xu, Jinwen; Dorje, Gaawe; Zhao, Zhili; Guo, Fujiang; Li, Yiming

2014-10-01

233

Influence of steviol glycosides on the stability of vitamin C and anthocyanins.  

PubMed

A high level of sweetness and health-promoting properties make steviol glycosides an interesting alternative to sugars or artificial sweeteners. The radical oxygen species scavenging activity of these compounds may influence the stability of labile particles present in food. Model buffer solutions containing steviol glycosides, a selected food antioxidant (vitamin C or anthocyanins), and preservative were analyzed during storage. The addition of steviol glycosides at concentrations of 50, 125, and 200 mg/L increased the stability of both ascorbic and dehydroascorbic acid (degradation rates decreased up to 3.4- and 4.5-fold, respectively); the effect was intensified by higher sweetener concentrations and higher acidity of the solutions. Glycosides used alone did not affect the stability of anthocyanins; however, they enhanced the protective effect of sugars; half-life times increased by ca. 33% in the presence of sucrose (100 g/L) and by ca. 52% when both sucrose (100 g/L) and glycosides (total 200 mg/L) were used. Steviol glycosides concentrations remained stable during experiments. PMID:25376304

Wo?niak, Lukasz; Marsza?ek, Krystian; Sk?pska, Sylwia

2014-11-19

234

Reverse logistics - a framework  

Microsoft Academic Search

In this paper we define and compare Reverse Logistics definitions. We start by giving an understanding framework of Reverse Logistics: the why-what-how. By this means, we put in context the driving forces for Reverse Logistics, a typology of return reasons, a classification of products, processes and actors. In addition we provide a decision framework for Reverse Logistics and we present

Marisa P. de Brito; Rommert Dekker

2002-01-01

235

[Triterpene glycosides from the aerial parts of Pulsatilla chinensis].  

PubMed

To study the chemical constituents of the aerial parts of Pulsatilla chinensis (Bge.) Regel, various chromatography methods were used. Seven triterpene glycosides were isolated from the n-BuOH extract. Their structures were identified as bayogenin 28-O-alpha-L-rhamnopyranosyl (1 --> 4 ) -beta-D-glucopyranosyl (1 --> 6) -beta-D-glucopyranosyl ester (1), 3-O-alpha-L-arabinopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1 --> 4) -beta-D-glucopyranosyl (1 --> 6) -beta-D-glucopyranosyl ester (2), 3-O-alpha-L-rhamnopyranosyl (1 -->-2 ) -alpha-L-arabinopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl (1 --> 4 ) -beta-D-glucopyranosyl (1 --> 6 ) -beta-D-glucopyranosyl ester (3), 3-O-alpha-L-rhamnopyranosyl (1 --> 2 ) -[beta-D-glucopyranosyl (1 --> 4)] -alpha-L-arabinopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1 --> 4) -beta-D-glucopyranosyl (1 --> 6) -beta-D-glucopyranosyl ester (4), 3-O-alpha-L-rhamnopyranosyl (1 --> 2) -alpha-L-arabinopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1 --> 4) -beta-D-glucopyranosyl (1 --> 6 ) -beta-D-glucopyranosyl ester (5), hederagenin 28-O-alpha-L-rhamnopyranosyl (1 --> 4) -beta-D-glucopyranosyl (1 --> 6) -beta-D-glucopyranosyl ester (6) and pulsatilla saponin (7). Among them, compound 1 is a new compound. Compounds 2 -6 were isolated from this plant for the first time. PMID:17944236

Shi, Bao-Jun; Li, Qian; Zhang, Xiao-Qi; Wang, Ying; Ye, Wen-Cai; Yao, Xin-Sheng

2007-08-01

236

Polyketide Glycosides from Bionectria ochroleuca Inhibit Candida albicans Biofilm Formation.  

PubMed

One of the challenges presented by Candida infections is that many of the isolates encountered in the clinic produce biofilms, which can decrease these pathogens' susceptibilities to standard-of-care antibiotic therapies. Inhibitors of fungal biofilm formation offer a potential solution to counteracting some of the problems associated with Candida infections. A screening campaign utilizing samples from our fungal extract library revealed that a Bionectria ochroleuca isolate cultured on Cheerios breakfast cereal produced metabolites that blocked the in vitro formation of Candida albicans biofilms. A scale-up culture of the fungus was undertaken using mycobags (also known as mushroom bags or spawn bags), which afforded four known [TMC-151s C-F (1-4)] and three new [bionectriols B-D (5-7)] polyketide glycosides. All seven metabolites exhibited potent biofilm inhibition against C. albicans SC5314, as well as exerted synergistic antifungal activities in combination with amphotericin B. In this report, we describe the structure determination of the new metabolites, as well as compare the secondary metabolome profiles of fungi grown in flasks and mycobags. These studies demonstrate that mycobags offer a useful alternative to flask-based cultures for the preparative production of fungal secondary metabolites. PMID:25302529

Wang, Bin; You, Jianlan; King, Jarrod B; Cai, Shengxin; Park, Elizabeth; Powell, Douglas R; Cichewicz, Robert H

2014-10-24

237

Antioxidant chalcone glycosides and flavanones from Maclura (Chlorophora) tinctoria.  

PubMed

Four chalcone glycosides (1-4), including three new natural products, and three flavanones (5-7) were isolated from the methanol extract of stem bark of Maclura tinctoria. The new compounds have been characterized as 4'-O-beta-D-(2' '-p-coumaroyl)glucopyranosyl-4,2',3'-trihydroxychalcone (1), 4'-O-beta-D-(2' '-p-coumaroyl-6' '-acetyl)glucopyranosyl-4,2',3'-trihydroxychalcone (2), and 3'-(3-methyl-2-butenyl)-4'-O-beta-D-glucopyranosyl-4,2'-dihydroxychalcone (3); the known derivatives were elucidated as 4'-O-beta-D-(2' '-acetyl-6' '-cinnamoyl)glucopyranosyl-4,2',3'-trihydroxychalcone (4), eriodictyol 7-O-beta-D-glucopyranoside (5), naringenin (6), and naringenin 4'-O-beta-D-glucopyranoside (7). Their structures were determined by 1D and 2D NMR and ESIMS. The antioxidant activity of all the isolated compounds was determined by measuring free-radical-scavenging effects using two different assays, namely, the Trolox Equivalent Antioxidant Capacity (TEAC) assay and the coupled oxidation of beta-carotene and linoleic acid (autoxidation assay). The results showed that compound 3 was the most active in both antioxidant assays. PMID:12932124

Cioffi, Giuseppina; Morales Escobar, Luis; Braca, Alessandra; De Tommasi, Nunziatina

2003-08-01

238

Antioxidative iridoid glycosides and phenolic compounds from Veronica peregrina.  

PubMed

Eight iridoid glycosides and four phenolic compounds were isolated from the EtOAc soluble fraction of Veronica peregrina MeOH extract as the radical scavengers for antioxidant activity. The compounds were identified as protocatechuic acid (1), luteolin (2), veronicoside (3), minecoside (4), specioside (5), amphicoside (6), catalposide (7), 6-O-cis-p-coumaroyl catalpol (8), p-hydroxy benzoic acid methyl ester (9), verproside (10), verminoside (11), and chrysoeriol 7-glucuronide (12) by spectroscopic analysis. All compounds except for 1 and 2 were isolated for the first time from this plant. The antioxidant activity was evaluated by the ORAC(Oxygen Radical Absorbance Capacity) assay, which measures scavenging activity against peroxy radicals induced by 2,2'-azobis (2-methoxypropion-amidine) dihydrochloride, and the ORAC value is expressed as relative trolox equivalent. Compounds 2, 4, 5, 6, 8, and 12 exhibited potent antioxidant activity, and compounds 1, 11 had similar activity with trolox, whereas the other compounds showed weaker activity than trolox. PMID:19280150

Kwak, Jong Hwan; Kim, Hyun Jung; Lee, Kwang Ho; Kang, Se Chan; Zee, Ok Pyo

2009-02-01

239

Antitrypanosomal isothiocyanate and thiocarbamate glycosides from Moringa peregrina.  

PubMed

O-Methyl (1), O-ethyl (2), and O-butyl (3) 4-[(?-L-rhamnosyloxy) benzyl] thiocarbamate (E), along with 4-(?-L-rhamnosyloxy) benzyl isothiocyanate (4) have been isolated from the aerial parts of Moringa peregrina. The compounds were tested for in vitro activity against Trypanosoma brucei rhodesiense and cytotoxicity in rat skeletal myoblasts (L6 cells). The most potent compound was 4 with an IC50 of 0.10 µM against T.b. rhodesiense and a selectivity index of 73, while the thiocarbamate glycosides 1, 2, and 3 showed only moderate activity. Intraperitoneal administration of 50 mg/kg body weight/day of 4 in the T.b. rhodesiense STIB 900 acute mouse model revealed significant in vivo toxicity. Administration of 10 mg/kg body weight/day resulted in a 95% reduction of parasitemia on day 7 postinfection, but did not cure the animals. Because of its high in vitro activity and its ability to irreversibly inhibit trypanothione reductase, an attractive parasite-specific target enzyme, 4-[(?-L-rhamnosyloxy) benzyl] isothiocyanate (4), can be considered as a lead structure for the development and characterization of novel antitrypanosomal drugs. PMID:24310210

Ayyari, Mahdi; Salehi, Peyman; Ebrahimi, Samad Nejad; Zimmermann, Stefanie; Portmann, Lena; Krauth-Siegel, R Luise; Kaiser, Marcel; Brun, Reto; Rezadoost, Hassan; Rezazadeh, Shamsali; Hamburger, Matthias

2014-01-01

240

Glycosidic moiety changes the spectroscopic properties of dl-?-tocopherol in DMSO\\/water solution and in organic solvents  

Microsoft Academic Search

In this study we estimated how conjugation with a sugar moiety influences the spectral properties of tocopherol and relate the spectroscopic properties of glycosides to solvent properties such as viscosity and polarity.Spectroscopic properties (absorption, fluorescence, fluorescence anisotropy and fluorescence lifetime) of three dl-?-tocopheryl glycosides (dl-?-tocopheryl orthoacetate derivative and glycosides of dl-?-tocopherol model compounds: 2,2,5,7,8-pentamethyl-6-chromanol and Trolox) were studied in DMSO\\/water

G. Neunert; P. Polewski; P. Walejko; M. Markiewicz; S. Witkowski; K. Polewski

2009-01-01

241

FeCl3-promoted and ultrasound-assisted synthesis of resveratrol O-derived glycoside analogs.  

PubMed

Phenol derived O-glycosides were synthesized using a direct and convenient O-glycosidation, starting from acetylated sugars in the presence of FeCl3, an inexpensive, mild and benign Lewis acid catalyst. The reactions were carried out under both conventional and ultrasonic irradiation conditions. In general, improvement in rates and yields were observed when reactions were carried out under sonication compared with conventional conditions leading to the corresponding ?-O-glycosides as the major anomer. Post-synthetic transformations of iodophenol intermediates led to new resveratrol O-glycoside analogs in good overall yields. PMID:24961448

Marzag, Hamid; Robert, Guillaume; Dufies, Maeva; Bougrin, Khalid; Auberger, Patrick; Benhida, Rachid

2015-01-01

242

HIV-1 Reverse Transcription  

PubMed Central

Reverse transcription and integration are the defining features of the Retroviridae; the common name “retrovirus” derives from the fact that these viruses use a virally encoded enzyme, reverse transcriptase (RT), to convert their RNA genomes into DNA. Reverse transcription is an essential step in retroviral replication. This article presents an overview of reverse transcription, briefly describes the structure and function of RT, provides an introduction to some of the cellular and viral factors that can affect reverse transcription, and discusses fidelity and recombination, two processes in which reverse transcription plays an important role. In keeping with the theme of the collection, the emphasis is on HIV-1 and HIV-1 RT. PMID:23028129

Hu, Wei-Shau; Hughes, Stephen H.

2012-01-01

243

Antioxidant constituents and a new triterpenoid glycoside from Flos Lonicerae.  

PubMed

As a component of our continuing investigations into herb-derived antioxidant agents, we have evaluated the antioxidant effects of Flos Lonicerae (Lonicera japonica flowers), via 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, total reactive oxygen species (ROS), hydroxyl radical (*OH), and peroxynitrite (ONOO-) assays. Among the methanolic extract and the dichloromethane, ethyl acetate, n-butanol, and water fractions, the EtOAc fraction of Flos Lonicerae exhibited marked scavenging/inhibitory activities, as follows: IC50 values of 4.37, 27.58 +/- 0.71, 0.47 +/- 0.05, and 12.13 +/- 0.79 microg/mL in the DPPH, total ROS, ONOO-, and *OH assays, respectively. Via a bioactivity-guided fractionation approach, a new triterpenoid glycoside, oleanolic acid 28-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-xylopyranosyl(1-->6)]-beta-D-glucopyranosyl ester (12), along with eleven known compounds, including chrysoeriol (1), luteolin (2), 5-hydroxymethyl-2-furfural (3), caffeic acid (4), protocatechuic acid (5), chrysoeriol 7-O-beta-D-glucopyranoside (6), isorhamnetin 3-O-beta-D-glucopyranoside (7), kaempferol 3-O-beta-D-glucopyranoside (8), quercetin 3-O-beta-D-glucopyranoside (9), hederagenin 3-O-alpha-L-arabinopyranoside (10), and luteolin 7-O-beta-D-glucopyranoside (11), were isolated from the EtOAc fraction. The structures of isolated compounds 1-12 were elucidated via spectroscopic analyses. Compound 12 was isolated from a natural source for the first time. Compounds 2, 4, 5, 7, 9, and 11 evidenced marked scavenging activities, with IC50 values of 2.08-11.76 microM for DPPH radicals, and 1.47-6.98 microM for ONOO-. PMID:17328234

Choi, Chun-Whan; Jung, Hyun Ah; Kang, Sam Sik; Choi, Jae Sue

2007-01-01

244

Bioprospecting metagenomics of decaying wood: mining for new glycoside hydrolases  

PubMed Central

Background To efficiently deconstruct recalcitrant plant biomass to fermentable sugars in industrial processes, biocatalysts of higher performance and lower cost are required. The genetic diversity found in the metagenomes of natural microbial biomass decay communities may harbor such enzymes. Our goal was to discover and characterize new glycoside hydrolases (GHases) from microbial biomass decay communities, especially those from unknown or never previously cultivated microorganisms. Results From the metagenome sequences of an anaerobic microbial community actively decaying poplar biomass, we identified approximately 4,000 GHase homologs. Based on homology to GHase families/activities of interest and the quality of the sequences, candidates were selected for full-length cloning and subsequent expression. As an alternative strategy, a metagenome expression library was constructed and screened for GHase activities. These combined efforts resulted in the cloning of four novel GHases that could be successfully expressed in Escherichia coli. Further characterization showed that two enzymes showed significant activity on p-nitrophenyl-?-L-arabinofuranoside, one enzyme had significant activity against p-nitrophenyl-?-D-glucopyranoside, and one enzyme showed significant activity against p-nitrophenyl-?-D-xylopyranoside. Enzymes were also tested in the presence of ionic liquids. Conclusions Metagenomics provides a good resource for mining novel biomass degrading enzymes and for screening of cellulolytic enzyme activities. The four GHases that were cloned may have potential application for deconstruction of biomass pretreated with ionic liquids, as they remain active in the presence of up to 20% ionic liquid (except for 1-ethyl-3-methylimidazolium diethyl phosphate). Alternatively, ionic liquids might be used to immobilize or stabilize these enzymes for minimal solvent processing of biomass. PMID:21816041

2011-01-01

245

Bioprospecting metagenomics of decaying wood: mining for new glycoside hydrolases  

SciTech Connect

To efficiently deconstruct recalcitrant plant biomass to fermentable sugars in industrial processes, biocatalysts of higher performance and lower cost are required. The genetic diversity found in the metagenomes of natural microbial biomass decay communities may harbor such enzymes. Our goal was to discover and characterize new glycoside hydrolases (GHases) from microbial biomass decay communities, especially those from unknown or never previously cultivated microorganisms. From the metagenome sequences of an anaerobic microbial community actively decaying poplar biomass, we identified approximately 4,000 GHase homologs. Based on homology to GHase families/activities of interest and the quality of the sequences, candidates were selected for full-length cloning and subsequent expression. As an alternative strategy, a metagenome expression library was constructed and screened for GHase activities. These combined efforts resulted in the cloning of four novel GHases that could be successfully expressed in Escherichia coli. Further characterization showed that two enzymes showed significant activity on p-nitrophenyl-{alpha}-L-arabinofuranoside, one enzyme had significant activity against p-nitrophenyl-{beta}-D-glucopyranoside, and one enzyme showed significant activity against p-nitrophenyl-{beta}-D-xylopyranoside. Enzymes were also tested in the presence of ionic liquids. Metagenomics provides a good resource for mining novel biomass degrading enzymes and for screening of cellulolytic enzyme activities. The four GHases that were cloned may have potential application for deconstruction of biomass pretreated with ionic liquids, as they remain active in the presence of up to 20% ionic liquid (except for 1-ethyl-3-methylimidazolium diethyl phosphate). Alternatively, ionic liquids might be used to immobilize or stabilize these enzymes for minimal solvent processing of biomass.

Li L. L.; van der Lelie D.; Taghavi, S.; McCorkle, S. M.; Zhang, Y.-B.; Blewitt, M. G.; Brunecky, R.; Adney, W. S.; Himmel, M. E.; Brumm, P.; Drinkwater, C.; Mead, D. A.; Tringe, S. G.

2011-08-01

246

Characterization of Five ?-Glycoside Hydrolases from Cellulomonas fimi ATCC 484.  

PubMed

The Gram-positive bacterium Cellulomonas fimi produces a large array of carbohydrate-active enzymes. Analysis of the collection of carbohydrate-active enzymes from the recent genome sequence of C. fimi ATCC 484 shows a large number of uncharacterized genes for glycoside hydrolase (GH) enzymes potentially involved in biomass utilization. To investigate the enzymatic activity of potential ?-glucosidases in C. fimi, genes encoding several GH3 enzymes and one GH1 enzyme were cloned and recombinant proteins were expressed in Escherichia coli. Biochemical analysis of these proteins revealed that the enzymes exhibited different substrate specificities for para-nitrophenol-linked substrates (pNP), disaccharides, and oligosaccharides. Celf_2726 encoded a bifunctional enzyme with ?-d-xylopyranosidase and ?-l-arabinofuranosidase activities, based on pNP-linked substrates (CfXyl3A). Celf_0140 encoded a ?-d-glucosidase with activity on ?-1,3- and ?-1,6-linked glucosyl disaccharides as well as pNP-?-Glc (CfBgl3A). Celf_0468 encoded a ?-d-glucosidase with hydrolysis of pNP-?-Glc and hydrolysis/transglycosylation activities only on ?-1,6-linked glucosyl disaccharide (CfBgl3B). Celf_3372 encoded a GH3 family member with broad aryl-?-d-glycosidase substrate specificity. Celf_2783 encoded the GH1 family member (CfBgl1), which was found to hydrolyze pNP-?-Glc/Fuc/Gal, as well as cellotetraose and cellopentaose. CfBgl1 also had good activity on ?-1,2- and ?-1,3-linked disaccharides but had only very weak activity on ?-1,4/6-linked glucose. PMID:25225266

Gao, Juan; Wakarchuk, Warren

2014-12-01

247

Phenolic Glycosides with antiproteasomal activity from Centaurea urvillei DC. subsp. urvillei.  

PubMed

A new flavanone glycoside, naringenin-7-O-?-D-glucuronopyranoside, and a new flavonol glycoside, 6-hydroxykaempferol-7-O-?-D-glucuronopyranoside were isolated together with 12 known compounds, 5 flavone glycoside; hispidulin-7-O-?-D-glucuronopyranoside, apigenin-7-O-?-D-methylglucuronopyranoside, hispidulin-7-O-?-D-methylglucuronopyranoside, hispidulin-7-O-?-D-glucopyranoside, apigenin-7-O-?-D-glucopyranoside, a flavonol; kaempferol, two flavone; apigenin, and luteolin, a flavanone glycoside; eriodictyol-7-O-?-D-glucuronopyranoside, and three phenol glycoside; arbutin, salidroside, and 3,5-dihydroxyphenethyl alcohol-3-O-?-D-glucopyranoside from Centaurea urvillei subsp. urvillei. The structure elucidation of the new compounds was achieved by a combination of one- ((1)H and (13)C) and two-dimensional NMR techniques (G-COSY, G-HMQC, and G-HMBC) and LC-ESI-MS. The isolated compounds were tested for their antiproteasomal activity. The results indicated that kaempferol, a well known and widely distributed flavonoid in the plant kingdom, was the most active antiproteasomal agent, followed by apigenin, eriodictyol-7-O-?-D-glucuronopyranoside, 3,5-dihydroxyphenethyl alcohol-3-O-?-D-glucopyranoside, and salidroside, respectively. PMID:20937505

Gülcemal, Derya; Alanku?-Çal??kan, Ozgen; Karaalp, Canan; Ors, Ahmet Uygar; Ballar, Petek; Bedir, Erdal

2010-11-22

248

Isolation of some glycosides as aroma precursors in young leaves of Japanese pepper (Xanthoxylum piperitum DC.).  

PubMed

To clarify the formation mechanism for the major alcoholic aroma compounds in young leaves of Japanese pepper, the glycosides were isolated as aroma precursors. The presence of glycosides of the main alcoholic aroma constituents was indirectly determined by enzymatic hydrolysis and trifluoroacetylation (TFA) of the glycoside-containing fraction. After Amberlite XAD-2 column chromatography, ODS flash chromatography, and high-performance liquid chromatography (HPLC), two new compounds, namely, (3S,6S)-cis-linalool-3,7-oxide beta-D-glucopyranoside and 2-methylpropanyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside, were isolated. In addition, (3S,6R)-cis-linalool-3,6-oxide beta-D-glucopyranoside, which absolute configuration was the first determined, and six known glycosides, citronellyl beta-D-glucopyranoside, linalyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside, (Z)-3-hexenyl beta-D-glucopyranoside, benzyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside, dendranthemoside A, and 3,6-dihydroxy-5,6-dihydro-beta-ionol 9-beta-D-glucopyranoside, were isolated. All of these glycosides were isolated for the first time from the leaves of Japanese pepper. Their structures were established on the basis of spectral data and chemical evidence. The ratios of stereoisomers of the aglycon moieties of citronellyl beta-D-glucopyranoside and linalyl 6-O-beta-D-apiofuranosyl-beta-D-glucopyranoside were investigated by a chiral GC analysis and compared with those of free citronellol and linalool in the aroma concentrate. PMID:11743780

Jiang, L; Kojima, H; Yamada, K; Kobayashi, A; Kubota, K

2001-12-01

249

Rapid identification of polyphenol C-glycosides from Swertia franchetiana by HPLC-ESI-MS-MS.  

PubMed

High-performance liquid chromatography coupled to positive ion electrospray ionization tandem mass spectrometry (MS) and diode array detection was employed to identify the polyphenol C-glycosides in the extract of Swertia franchetiana, a traditional Chinese/Tibetan herb. The neutral loss scan of the extract of S. franchetiana using the characteristic losses of 120 and 150 u provided a detailed profile of the polyphenol C-glycosides in the complex mixture. On-line UV spectroscopy along with MS-MS and MS-MS-MS mass spectra analysis produced with and without in-source collision induced dissociation was contributed to discriminate and identify the polyphenol C-glycosides. Three xanthone C-glycosides (i.e., mangiferin, isomangiferin, and 1,6,7-trihydroxyl-2-C-glucosexanthone) and three flavone C-glycosides (i.e., isoorientin, isovitexin, and swertisin) were tentatively identified. Isomangiferin and 1,6,7-trihydroxyl-2-C-glucosexanthone were for the first time found in this plant. PMID:19298704

Sun, Yanguo; Zhang, Xi; Xue, Xingya; Zhang, Yan; Xiao, Hongbin; Liang, Xinmiao

2009-03-01

250

Reversion of flowering  

Microsoft Academic Search

Reversion from floral to vegetative growth is under environmental control in many plant species. However the factors regulating\\u000a floral reversion, and the events at the shoot apex that take place when it occurs, have received less attention than those\\u000a associated with the transition to flowering.\\u000a \\u000a Reversions may be categorized as flower reversion, in which the flower meristem resumes leaf production,

N. H. Battey; R. F. Lyndon

1990-01-01

251

Time reversal matched field  

Microsoft Academic Search

Time reversal techniques obtain increased resolution by exploiting scattering and multipath in propagation through inhomogeneous channels. Fink and collaborators has used time reversal to achieve super-resolution focusing in acoustics with controlled ultrasonic experiments in water tanks. More recently large-scale acoustics experiments in the ocean have confirmed the resolution ability of time reversal. In this paper, matched field detection with time

J. Moura

2004-01-01

252

Reverse Correlation in Neurophysiology  

ERIC Educational Resources Information Center

This article presents a review of reverse correlation in neurophysiology. We discuss the basis of reverse correlation in linear transducers and in spiking neurons. The application of reverse correlation to measure the receptive fields of visual neurons using white noise and m-sequences, and classical findings about spatial and color processing in…

Ringach, Dario; Shapley, Robert

2004-01-01

253

High-performance liquid chromatographic determination of secondary cardiac glycosides in Digitalis purpurea leaves.  

PubMed

An analytical method for the determination of secondary cardiac glycosides in Digitalis purpurea leaves by high-performance liquid chromatography (HPLC) is described. The procedure consisted of extraction of dry leaf powder with ethanol-chloroform (2:1) and clean-up by Sep-Pak cartridges prior to HPLC analysis. HPLC was performed on an octylsilyl bonded silica column, using acetonitrile-methanol-water (4:4:5) for trisdigitoxosides and acetonitrile-methanol-water (8:30:43) for strospeside; the effluent was monitored by ultraviolet detection (at 220 nm). Quantitation of these cardiac glycosides was carried out by the internal standard method. The amounts of digitoxin, gitoxin, gitaloxin and strospeside per 100 mg of dry leaf powder were estimated to be 22.6, 14.0, 54.7 and 1.9 micrograms, respectively. The method is sufficiently sensitive and reproducible to assay secondary glycosides in Digitalis purpurea leaves. PMID:2808604

Fujii, Y; Ikeda, Y; Yamazaki, M

1989-10-01

254

Glycosidic aroma precursors of Syrah and Chardonnay grapes after an oak extract application to the grapevines.  

PubMed

Syrah and Chardonnay grapevines were treated with an oak extract in order to determine the effect on glycosidic aroma precursors. Grapevines were treated at three different timings of the veraison (treatment 1, 2 and 3). Aglycons were obtained by enzymatic hydrolysis, and these were identified and quantified by means of gas chromatography-mass spectrometry (GC-MS). Results suggest that after the applications the majority of compounds from the oak extract were assimilated and stored as glycosidic forms in both cultivars. Also, other compounds not present in the extract were affected, with a different behaviour observed depending on the timing of application and the variety. In general, C6 compounds, alcohols, terpenes, phenols and C13-norisoprenoids in Syrah showed a decrease and in Chardonnay an increase. Thus, this study proved a change in the glycosidic aroma profile in grapes after the oak application, so these treated grapes could produce wines with different aromatic quality. PMID:23411201

Martínez-Gil, Ana M; Angenieux, Magaly; Pardo-García, Ana I; Alonso, Gonzalo L; Ojeda, Hernán; Rosario Salinas, M

2013-06-01

255

New insights into the structure-cytotoxicity relationship of spirostan saponins and related glycosides.  

PubMed

A variety of spirostan saponins and related glycosides were synthesized and evaluated for their cytotoxicity against the human myeloid leukemia cell line (HL-60). A linear glycosylation strategy allowed for accessing a variety of functionalization patterns at both the spirostanic and the saccharide moieties, which provides new information regarding the structure-cytotoxicity relationship of this family of steroidal glycosides. Intriguing results were achieved with respect to hecogenyl and 5?-hydroxy-laxogenyl ?-chacotriosides, turning out to be the former very cytotoxic and the latter no cytotoxic at all. Importantly, the partially pivaloylated ?-d-glucosides of 5?-hydroxy-laxogenin were the most potent cytotoxic compounds among all tested glycosides. This comprises the first report on acylated spirostanyl glucosides displaying significant cytotoxicity, and therefore, it opens up new opportunities toward the development of saponin analogues as anticancer agents. PMID:22405922

Pérez-Labrada, Karell; Brouard, Ignacio; Estévez, Sara; Marrero, María Teresa; Estévez, Francisco; Bermejo, Jaime; Rivera, Daniel G

2012-04-15

256

The flavonol glycosides in the fruit of Pyrus communis L. cultivar Bon Chrétien.  

PubMed

1. Two new flavonol glycosides were isolated from the fruit of Pyrus communis L. cultivar Bon Chrétien. These were identified as isorhamnetin 3-rhamnogalactoside and a derivative of isorhamnetin 3-glucoside which was associated (possibly acylated) with an unknown aliphatic organic acid. 2. The melting point of isorhamnetin 3-glucoside isolated from Bon Chrétien pears is different from that of isorhamnetin 3-glucoside previously isolated from Argemone mexicana and Calendula officinalis. 3. Isorhamnetin 3-rhamnoglucoside was isolated from the fruit of Pyrus communis L. cultivar Bon Chrétien. This glycoside appears to be identical with narcissin, previously isolated from Narcissus tazetta and Lilium auratum. 4. Isoquercitrin, previously reported to be present in pear leaves, was isolated from the fruit of Bon Chrétien pears. 5. The isolated glycosides were present in the peels and flesh of the fruit, but were absent from the cores. PMID:16749105

Nortjé, B K

1965-10-01

257

Resin glycosides from the roots of Ipomoea tyrianthina and their biological activity.  

PubMed

Seven new tetrasaccharide glycosides, tyrianthins 1-7 (1-7), along with six known glycolipids were isolated from the roots of Ipomoea tyrianthina, and their structures were elucidated by spectroscopic and chemical methods. The content of resin glycosides in samples collected in three different regions was analyzed and compared, and the results showed that the flowering or dry season did not have any effect on the chemical composition for the same locality, but the growing location itself did affect the chemical composition of resin glycosides. Intraperitoneal administration to mice of tyrianthin 6 (6) resulted in antidepressant activity. Tyrianthin 6 (6), scammonin 1 (8), and scammonin 2 (9) exhibited dose-dependent protective effects against pentylenetetrazole-induced seizures. Also, tyrianthin 6 (6) and scammonin 2 (9) produced relaxant effects on spontaneous contractions in the isolated rat ileum. PMID:17309299

Mirón-López, Gumersindo; Herrera-Ruiz, Maribel; Estrada-Soto, Samuel; Aguirre-Crespo, Francisco; Vazquez-Navarrete, Lorena; León-Rivera, Ismael

2007-04-01

258

Two New Quinochalcone C-Glycosides from the Florets of Carthamus tinctorius  

PubMed Central

Two new quinochalcone C-glycosides, named hydroxysafflor yellow B (1) and hydroxysafflor yellow C (2), along with two known quinochalcone C-glycosides, safflomin C (3) and saffloquinoside C (4), and one known flavanone, (2R)-4',5-dihydroxyl-6,7-di-O-?-d-glucopyranosyl flavanone (5), were isolated from the florets of Carthamus tinctorius. Their structures were determined by extensive spectroscopic (UV, IR, HR-ESI-MS, 1D and 2D NMR) analyses. In addition, these quinochalcone C-glycosides together with hydroxysafflor yellow A and anhydrosafflor yellow B were evaluated for their anti-oxidative effects against H2O2-induced cytotoxicity in cultured H9c2 cells. Among them, compound 2 exhibited significant anti-oxidative effects. PMID:25247575

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

2014-01-01

259

Re-evaluating the role of ascorbic acid and phenolic glycosides in ozone scavenging in the leaf apoplast of  

E-print Network

Re-evaluating the role of ascorbic acid and phenolic glycosides in ozone scavenging in the leaf of ascorbic acid (AA) and phenolic glycosides in Arabidopsis thaliana L. Col-0 wild-type plants were- ucts (Mudd 1996; Wohlgemuth et al. 2002). Primarily, ascorbic acid (AA) in the apoplast is thought

Jones, Alan M.

260

Synthesis and conformational behavior of the difluoromethylene linked C-glycoside analog of ?-galactopyranosyl-(1<->1)-?-mannopyranoside  

PubMed Central

Exact C-glycosides in which the glycosidic oxygen of an O-glycoside is replaced with a methylene group have been advertised as hydrolytically stable mimetics of their parent O-glycosides. While this substitution assures greater stability, the lower polarity and increased conformational flexibility in the intersaccharide linker brought about by this change may compromise biological mimicry. In this regard, C-glycosides in which the pseudoanomeric methylene is replaced with a difluoromethylene group are interesting because the CF2 group is more of an isopolar replacement for oxygen than a CH2. In addition, the CF2 residue is expected to instill conformational bias into the intersaccharide torsions. Herein is described the synthesis and conformational behavior of the difluoromethylene linked C-glycoside of ?-d-galactopyranosyl-(1?1)-?-d-mannopyranoside. The synthesis centers on the formation of the galactose residue via an oxocarbenium ion-enol ether cyclization. Conformational analysis, using a combination of molecular mechanics, dynamics and NMR spectroscopy. suggests that the difluoro-C-glycoside populates the non-exo-Gal/exo-Man conformer to a major extent (ca 50%), with a minor contribution (?15%) from the exo-Gal/exo-Man conformer that corresponds to the ground sate of the parent O-glycoside. PMID:17601514

Denton, Richard W.; Tony, Kurissery A.; Hernandez-Gay, Jose Juan; Canada, F. Javier; Jimenez-Barbero, Jesus; Mootoo, David R.

2007-01-01

261

Iridoid glycosides of Chelone glabra (Scrophulariaceae) and their sequestration by larvae of a sawfly, Tenthredo grandis (Tenthredinidae)  

Microsoft Academic Search

Analysis ofChelone glabra (Scrophulariaceae) by gas chromatography showed that leaves of this plant contained primarily the iridoid glycoside catalpol, and in a few individuals some aucubin was also detected. There was no difference in the iridoid glycoside content of damaged compared to undamaged plants, nor was there a difference between plants collected from a population in Leverett, Massachusetts, and those

M. Deane Bowers; Kenneth Boockvar; Sharon K. Collinge

1993-01-01

262

Quantitative determination of triterpenoid glycosides in Fatsia japonica Decne. & Planch. using high performance liquid chromatography.  

PubMed

Fatsia japonica Decne. & Planch. is a triterpenoid glycoside-rich herb with anti-inflammatory activity for the treatment of rheumatoid arthritis. A method for quantitative analysis of the complex triterpenoid glycosides in this medicinal plant has not been established so far. In this study, a high performance liquid chromatography (HPLC) method was developed for simultaneous qualification of 11 glycosides in F. japonica. The analysis was performed on an ODS-2 Hypersil column (250mm×4.6mm, 5?m) with a binary gradient mobile phase of water and acetonitrile. The established HPLC method was validated in terms of linearity, sensitivity, stability, precision, accuracy, and recovery. Results showed that this method had good linearity with R(2) at 0.99992-0.99999 in the test range of 0.04-9.00?g/?L. The limit of detection (LOD) and limit of quantification (LOQ) for the standard compounds were 0.013-0.020?g/?L and 0.040-0.060?g/?L. The relative standard deviations (RSDs%) of run variations were 0.83-1.40% for intra-day and 0.84-3.59% for inter-day. The analyzed compounds in the samples were stable for at least 36h, and the spike recoveries of the detected glycosides were 99.67-103.11%. The developed HPLC method was successfully applied for the measurements of the contents of 11 triterpenoid glycoside in different parts of F. japonica. Taken together, the HPLC method newly developed in this study could be used for qualitative and quantitative analysis of the bioactive triterpenoid glycosides in F. japonica and its products. PMID:24176752

Ye, Xuewei; Yu, Siran; Lian, Xiao-Yuan; Zhang, Zhizhen

2014-01-01

263

INHIBITION OF INFLUENZA VIRUS MULTIPLICATION BY N-GLYCOSIDES OF BENZIMIDAZOLES  

PubMed Central

Chloro derivatives of benzimidazole were found to be 2 to 3 times more active than corresponding methyl derivatives in causing inhibition of Lee virus multiplication in chorioallantoic membrane cultures in vitro. The most active benzimidazole derivative thus far tested is 5,6-dichloro-1-?-D-ribofuranosylbenzimidazole (DRB); it caused 75 per cent inhibition of Lee virus multiplication in membrane cultures at a concentration of 0.38 x 10–4 M. On the other hand, 5,6-dimethyl-1-alpha;-D-ribofuranosylbenzimidazole, the moiety present in vitamin B12, failed to inhibit Lee virus multiplication at a concentration of 35 x 10–4 M. Other N-glycosides of 5,6-dichlorobenzimidazole were considerably less active than DRB. In single cycle experiments, the degree of inhibition of Lee virus multiplication by DRB in membrane cultures was not dependent on the amount of virus in the inoculum. This compound did not inactivate the infectivity of extracellular Lee virus, had no effect on virus-erythrocyte interaction, did not interfere with the adsorption of the virus by the host tissue, nor affect the release of newly formed virus from the membrane. The inhibitory effect of DRB on Lee virus multiplication, in contrast to that of 2,5-dimethylbenzimidazole, persisted after transfer of infected membranes into fresh culture medium not containing the compound. Both DRB and the 2,5-dimethyl compound caused 99 per cent inhibition of Lee virus multiplication without affecting oxygen uptake of the membrane. Tissue proliferation of membrane pieces in roller tube culture was not significantly affected by DRB at inhibitory concentration, whereas at equivalent concentration the 2,5-dimethyl compound did restrict cellular growth. At higher concentrations, both compounds caused retardation of cell proliferation. This effect was reversible on removal of either compound from the medium. The multiplication of several strains of influenza A and B viruses, i.e. Lee, MB, PR8, and FM1, was inhibited to the same degree by each of the two compounds; DRB was 35 times more active than the 2,5-dimethyl compound relative to each of the strains. DRB caused inhibition of Lee virus multiplication in intact embryonated chicken eggs and in mice without causing significant signs of toxicity in either host. Some of the implications of these findings are discussed in relation to the mechanism of the inhibition of influenza virus multiplication. PMID:13130796

Tamm, Igor; Folkers, Karl; Shunk, Clifford H.; Horsfall, Frank L.

1954-01-01

264

Electrospray ionization mass spectrometry of mixtures of triterpene glycosides with L-phenylalanine  

NASA Astrophysics Data System (ADS)

Electrospray-ionization mass spectrometry (ESI-MS) was used to investigate for the first time the molecular complexation of L-phenylalanine with hederagenin 3-O- ?- L-rhamnopyranosyl-(1 ? 2)-O- ?- L-arabinopyranoside ( ?-hederin) and its 28-O- ?- L-rhamnopyranosyl-(1 ? 4)-O-?- D-glucopyranosyl-(1 ? 6)-O-?- D-glucopyranosyl ester (hederasaponin C). The glycoside/ L-phenylalanine complexes with a 1:1 molar ratio turned out to be most stable. The structures of the glycosides and L-phenylalanine have been concluded to have an impact on the complexation process.

Lekar, A. V.; Vetrova, E. V.; Borisenko, N. I.; Yakovishin, L. A.; Grishkovets, V. I.; Borisenko, S. N.

2011-09-01

265

Molecular complexation of the triterpene glycoside hederasaponin C and caffeine in aqueous solution  

Microsoft Academic Search

Molecular complexation of the triterpene glycoside hederasaponin C [hederagenin 3-O-?-L-rhamnopyranosyl-(1?2)-O-?-L-arabinopyranosyl-28-O-?-L-rhamnopyranosyl-(1?4)-O-?-D-glucopyranosyl-(1?6)-O-?-D-glucopyranosyl ether] and caffeine in aqueous solution was studied by UV spectroscopy for the first time. The complex composition,\\u000a which included two glycosides and one caffeine, was determined using isomolar series and molar ratios. The ichthyotoxicity\\u000a of the complex and its components against Poecilia reticulata was studied.

L. A. Yakovishin

2010-01-01

266

Polyphenols of Egyptian Rosaceae plants--two new flavonoid glycosides from Sanguisorba minor Scop.  

PubMed

Two new flavonol glycosides, 8-methoxyquercetin-3-O-beta-glucosyl-(1'"-2")-O-beta-glucoside and kaempferol-3-O-[2'"-galloyl-O-beta-glucosyl-(1'"-2")-O-beta-glucoside)], together with five known quercetin and kaempferol 3-O-mono-glycosides, were isolated and identified from the aerial parts of Sanguisorba minor Scop. (Rosaceae). All structures were determined by routine methods of analysis and confirmed mostly by negative ESI-MS, 1H- and 13C NMR. PMID:12426953

el-Mousallamy, A M D

2002-10-01

267

Ether-soluble resin glycosides from the roots of Ipomoea batatas.  

PubMed

Two new resin glycosides, batataosides I (1) and II (2), and five known compounds, friedelin (3), scopoletin (4), octadecyl caffeate (5), beta-sistosterol (6) and daucosterol (7), were isolated from the roots of Ipomoea batatas. Their structures have been determined based on the chemical and spectral data. Batataosides I and II have novel structures because the core simonic acid B was esterised with cinnamic acid for the first time, and three different substituent esterification groups in one resin glycoside is scarce. The absolute configuration of the aglycone was elucidated to be S by Mosher's method. PMID:18335340

Yin, Yong-Qin; Kong, Ling-Yi

2008-01-01

268

Electrospray-ionization mass spectrometry of mixtures of triterpene glycosides with paracetamol  

NASA Astrophysics Data System (ADS)

Molecular complexation of paracetamol with hederagenin 3-O-?-L-rhamnopyranosyl-(1 ? 2)-O-?-L-arabinopyranoside (?-hederin) and its 28-O-?-L-rhamnopyranosyl-(1 ? 4)-O-?-D-glucopyranosyl-(1 ? 6)-O-?-Dglucopyranosyl ether (hederasaponin C) was investigated for the first time using electrospray-ionization mass spectrometry (ESI-MS). The glycosides form complexes with paracetamol in a 1:1 molar ratio. The hederasaponin C complex is more stable. The structures of the glycosides and paracetamol are concluded to have an impact on the complexation process.

Lekar, A. V.; Vetrova, E. V.; Borisenko, N. I.; Yakovishin, L. A.; Grishkovets, V. I.

2010-11-01

269

Synthesis of O- and C-glycosides derived from ?-(1,3)-D-glucans.  

PubMed

A series of ?-(1,3)-d-glucans have been synthesized incorporating structural variations specifically on the reducing end of the oligomers. Both O- and C-glucosides derived from di- and trisaccharides have been obtained in good overall yields and with complete selectivity. Whereas the O-glycosides were obtained via a classical Koenigs-Knorr glycosylation, the corresponding C-glycosides were obtained through allylation of the anomeric carbon and further cross-metathesis reaction. Finally, the compounds were evaluated against two glycosidases and two endo-glucanases and no inhibitory activity was observed. PMID:24140893

Marca, Eduardo; Valero-Gonzalez, Jessika; Delso, Ignacio; Tejero, Tomás; Hurtado-Guerrero, Ramon; Merino, Pedro

2013-12-15

270

Flavonoid glycosides of spore-bearing stems of Equisetum arvense  

Microsoft Academic Search

In an extract of spore-bearing stems ofEquisetum arvense L. (field horsetail) saponaretin, apigenin 5-glucoside, luteolin 5-glucoside, kaempferol 3-sophoroside, quercetin 3-glucoside, 4-hydroxy-6-(2-hydroxyethyl)-2,2,5,7-tetramethylindanone, and a compound of ketonic nature, isolated previously from an extract of the herbage of the field horsetail, have been identified by high-performance liquid chromatography. The characteristics of the chromatographic behavior of glycosylated flavones under the conditions of reversed-phase

A. I. Syrchina; V. G. Gorokhova; N. A. Tyukavkina; V. A. Babkin; M. G. Voronkov

1980-01-01

271

Evaluation of the glycoside hydrolase activity of a Brettanomyces strain on glycosides from sour cherry (Prunus cerasus L.) used in the production of special fruit beers.  

PubMed

The glycoside hydrolase activity of Saccharomyces cerevisiae and Brettanomyces custersii was examined on sour cherry (Prunus cerasus L.) glycosides with bound volatile compounds. Refermentations by the beta-glucosidase-negative S. cerevisiae strains LD25 and LD40 of sour cherry juice-supplemented beer demonstrated only a moderate increase of volatiles. In contrast, the beta-glucosidase-positive B. custersii strain LD72 showed a more pronounced activity towards glycosides with aliphatic alcohols, aromatic compounds and terpenoid alcohols. Important contributors to sour cherry aroma such as benzaldehyde, linalool and eugenol were released during refermentation as shown by analytical tools. A gradually increasing release was observed during refermentations by B. custersii when whole sour cherries, sour cherry pulp or juice were supplemented in the beer. Refermentations with whole sour cherries and with sour cherry stones demonstrated an increased formation of benzyl compounds. Thus, amygdalin was partially hydrolysed, and a large part of the benzaldehyde formed was mainly reduced to benzyl alcohol and some further esterified to benzyl acetate. These findings demonstrate the importance and interesting role of certain Brettanomyces species in the production of fruit lambic beers such as 'Kriek'. PMID:18673394

Daenen, Luk; Sterckx, Femke; Delvaux, Freddy R; Verachtert, Hubert; Derdelinckx, Guy

2008-11-01

272

Preparative isolation and purification of five flavonoid glycosides and one benzophenone galloyl glycoside from Psidium guajava by high-speed counter-current chromatography (HSCCC).  

PubMed

Psidium guajava leaves have a diverse phytochemical composition including flavonoids, phenolics, meroterpenoids and triterpenes, responsible for the biological activities of the medicinal parts. In particular, flavonol glycosides show beneficial effects on type II diabetes mellitus. A simple and efficient HSCCC method has been developed for the preparative separation of five flavonoid glycosides and one diphenylmethane glycoside from P. guajava. A solvent system composed of n-hexane-ethyl acetate-methanol-water (0.7:4:0.8:4, v/v/v/v) was optimized for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. Under the optimized conditions, hyperoside (15.3 mg), isoquercitrin (21.1 mg), reynoutrin (65.2 mg), quercetin-3-O-?-D-arabinopyranoside (71.7 mg), quercetin-3-O-?-L-arabinofuranoside (105.6 mg) and 2,4,6-trihydroxy-3,5-dimethylbenzophenone 4-O-(6''-O-galloyl)-?-D-glucopyranoside (98.4 mg) were separated from crude sample (19.8 g). The structures of all the isolates were identified by ESI-MS, 1H- and 13C-NMR analyses and their purities (>95%) were determined using HPLC. PMID:24352020

Zhu, Yindi; Liu, Yue; Zhan, Ying; Liu, Lin; Xu, Yajuan; Xu, Tunhai; Liu, Tonghua

2013-01-01

273

7-O-methylpelargonidin glycosides from the pale red flowers of Catharanthus roseus.  

PubMed

Two new anthocyanidin glycosides were isolated from the pale red flowers of Catharanthus roseus 'Equator Apricot with Red Eye', and identified as 7-O-methylpelargonidin 3-O-[6-O-(alpha-rhamnopyranosyl)-beta-galactopyranoside] and 7-O-methylpelargonidin 3-O-(beta-galactopyranoside) by chemical and spectroscopic methods. PMID:24079176

Tatsuzawa, Fumi

2013-08-01

274

Hesperidin and hesperetin membrane interaction: Understanding the role of 7- O-glycoside moiety in flavonoids  

Microsoft Academic Search

Citrus species contain various typical flavonoids. However, absorption and metabolism of flavonoids are complex processes that determine its bioavailability which remain not clear until now.The aim of this study was to investigate the interactions among dimyristoyl-phosphatidyl choline (DMPC) liposomes and the flavanones hesperidin (glycoside) and hesperetin (aglycone). The results describe the molecular details of these interactions and the consequences for

Julián Londoño-Londoño; Vânia Rodrigues De Lima; Consuelo Jaramillo; Tânia Creczynski-pasa

2010-01-01

275

Hydrolysis of terpenyl glycosides in grape juice and other fruit juices: a review  

Microsoft Academic Search

The importance of monoterpenes on varietal flavour of must and other fruit juices has been reviewed. These compounds were mainly found linked to sugar moieties in grape juice and wines, showing no olfactory characteristics. In this way, analytical techniques developed to study these compounds, in both free or glycosidically forms, are discussed. Mechanisms to liberate terpenes were studied, making a

Sergi Maicas; José Juan Mateo

2005-01-01

276

Violarvensin, a new flavone di-C-glycoside from Viola arvensis.  

PubMed

A new flavonoid di-C-glycoside, violarvensin (1), was isolated from the aerial parts of Viola arvensis, together with the known derivative violanthin (2). The structure of 1 was established as apigenin-6-C-beta-D-glucopyranosyl-8-C-beta-D-6-deoxygulopyrano side by spectral analysis. PMID:9548860

Carnat, A P; Carnat, A; Fraisse, D; Lamaison, J L; Heitz, A; Wylde, R; Teulade, J C

1998-02-01

277

Medicinal flowers. XXX. Eight new glycosides, everlastosides F-M, from the flowers of Helichrysum arenarium.  

PubMed

Eight new glycosides, everlastosides F (1), G (2), H (3), I (4), J (5), K (6), L (7), and M (8), were isolated from the methanolic extract of the flowers of Helichrysum arenarium. Their structures were elucidated on the basis of chemical and physicochemical evidence. PMID:19652412

Morikawa, Toshio; Wang, Li-Bo; Ninomiya, Kiyofumi; Nakamura, Seikou; Matsuda, Hisashi; Muraoka, Osamu; Wu, Li-Jun; Yoshikawa, Masayuki

2009-08-01

278

A novel antimicrobial flavonoidic glycoside from the leaves of Alstonia macrophylla Wall ex A. DC (Apocynaceae)  

Microsoft Academic Search

A new flavonoidic glycoside, tricin-4?-O-?-l-arabinoside (1) was isolated from the leaves of Alstonia macrophylla along with two known flavonoids, vitexin and myricetin-3?-rhamnoside-3-O-galactoside. Their structures were established by chemical and spectral evidences. The known compounds were reported for the first time from this plant. Moreover compound 1 was tested for antifungal and antibacterial activities.

Mehtab Parveen; Zakia Khanam; Akhtar Ali; Syed Mohmud Ahmad

2010-01-01

279

A potential antiviral flavone glycoside from the seeds of Butea monosperma O. Kuntze.  

PubMed

A potential antiviral flavone glycoside has been isolated from the seeds of Butea monosperma O. Kuntze and its structure determined as 5,2'-dihydroxy-3,6,7-trimethoxyflavone-5-O-beta-D-xylopyranosyl-(1-->4)-O-beta-D-glucopyranoside (1) by various spectral analysis and chemical degradations. PMID:15621625

Yadava, R N; Tiwari, Lata

2005-04-01

280

Note: A potential antiviral flavone glycoside from the seeds of Butea monosperma O. Kuntze  

Microsoft Academic Search

A potential antiviral flavone glycoside has been isolated from the seeds of Butea monosperma O. Kuntze and its structure determined as 5,2?-dihydroxy-3,6,7-trimethoxyflavone-5-O-?-d-xylopyranosyl-(1?4)-O-?-d-glucopyranoside (1) by various spectral analysis and chemical degradations.

R. N. Yadava; Lata Tiwari

2005-01-01

281

Benzyl benzoate glycoside and 3-deoxy-D-manno-2-octulosonic acid derivatives from Solidago decurrens.  

PubMed

A new benzyl benzoate glycoside and five new 3-deoxy-D-manno-2-octulosonic acid derivatives were isolated from the entire plant of Solidago decurrens together with three known compounds. Their structures were established by extensive analyses of their 1D and 2D NMR spectra and by comparison with physical data of known compounds. PMID:22185651

Shiraiwa, Ken; Yuan, Shen; Fujiyama, Ayako; Matsuo, Yosuke; Tanaka, Takashi; Jiang, Zhi-Hong; Kouno, Isao

2012-01-27

282

Aspergillus niger DLFCC-90 Rhamnoside Hydrolase, a New Type of Flavonoid Glycoside Hydrolase  

PubMed Central

A novel rutin-?-l-rhamnosidase hydrolyzing ?-l-rhamnoside of rutin, naringin, and hesperidin was purified and characterized from Aspergillus niger DLFCC-90, and the gene encoding this enzyme, which is highly homologous to the ?-amylase gene, was cloned and expressed in Pichia pastoris GS115. The novel enzyme was classified in glycoside-hydrolase (GH) family 13. PMID:22544243

Liu, Tingqiang; Zhang, Chunzhi; Lu, Mingchun; Piao, Yongzhe; Ohba, Masashi; Tang, Minqian; Yuan, Xiaodong; Wei, Shenghua; Wang, Kan; Ma, Anzhou; Feng, Xue; Qin, Siqing; Mukai, Chisato; Tsuji, Akira

2012-01-01

283

Targeted Discovery of Glycoside Hydrolases from a Switchgrass-Adapted Compost Community  

E-print Network

@lbl.gov Introduction Enzymatic hydrolysis is one of the most expensive steps in biofuel production from lignocellulosic Development of cellulosic biofuels from non-food crops is currently an area of intense research interest encoding glycoside hydrolase domains that were biased toward depolymerizing grass cell wall components

Hazen, Terry

284

Gas Chromatographic – Mass Spectrometric Cardiotonic Glycosides Detection in Equine Urine Doping Analysis  

Microsoft Academic Search

A screening method for the detection of cardiotonic glycosides in horse’s urine is presented in this paper. This method is based on the detection by gas chromatography -mass spectrometry (GC -MS) and gas chromatography -high resolution mass spectrometry (GC -HRMS) of the trimethylsilyl (TMS) derivatives of the aglycon moieties of these compounds after solid phase extraction and methanolysis, according to

P. Kiousi; Y. S. Angelis; M. Koupparis; D. Kouretas; N. Diakakis; A. Desiris; C. G. Georgakopoulos

2004-01-01

285

Effect of Iridoid Glycoside Content on Oviposition Host Plant Choice and Parasitism in a Specialist Herbivore  

Microsoft Academic Search

The Glanville fritillary butterfly Melitaea cinxia feeds upon two host plant species in Å land, Finland, Plantago lanceolataand Veronica spicata, both of which produce iridoid glycosides. Iridoids are known to deter feeding or decrease the growth rate of many generalist insect herbivores, but they often act as oviposition cues to specialist butterflies and are feeding stimulants to their larvae. In

Marko Nieminen; Johanna Suomi; Saskya Van Nouhuys; Pauliina Sauri; Marja-Liisa Riekkola

2003-01-01

286

EFFECT OF IRIDOID GLYCOSIDE CONTENT ON OVIPOSITION HOST PLANT CHOICE AND PARASITISM IN A SPECIALIST HERBIVORE  

Microsoft Academic Search

Abstract—The Glanville fritillary butterfly Melitaea cinxiafeeds upon two host plant species in ? Aland, Finland, Plantago lanceolataand Veronica spicata, both of which produce iridoid glycosides. Iridoids are known,to deter feeding or de- crease the growth rate of many generalist insect herbivores, but they often act as oviposition cues to specialist butterflies and are feeding stimulants to their larvae. In this

MARKO NIEMINEN; JOHANNA SUOMI; SASKYA VAN NOUHUYS; PAULIINA SAURI; MARJA-LIISA RIEKKOLA

2003-01-01

287

Extraction of iridoid glycosides and their determination by micellar electrokinetic capillary chromatography  

Microsoft Academic Search

Several methods for the extraction of two iridoid glycosides, catalpol and aucubin, from the plant matrix (Veronica longifolia leaves) were compared. Pressurized hot water extraction and hot water extraction were the most efficient isolation techniques for both. Pressurized liquid extraction and maceration with various organic solvents were also tested. Relative to the amounts extracted with hot water, ethanol extracted only

Johanna Suomi; Heli Sirén; Kari Hartonen; Marja-Liisa Riekkola

2000-01-01

288

?-Glucosidase inhibitory activities of phenylpropanoid glycosides, vanicoside A and B from Polygonum sachalinense rhizome  

Microsoft Academic Search

The phenylpropanoid glycosides, vanicoside A and B, isolated from rhizomes of giant knotweed (Polygonum sachalinense) showed ?-glucosidase inhibitory activity, with IC50 values of 59.8 and 48.3 ?g\\/ml (59.9 and 50.5 ?M), respectively. In contrast, p-coumaric acid and ferulic acid, corresponding to phenylpropanoyl moieties of vanicosides, exhibited very little inhibition.

Y. Kawai; H. Kumagai; H. Kurihara; K. Yamazaki; R. Sawano; N. Inoue

2006-01-01

289

Phase transfer catalysis toward the synthesis of O-, S-, Se and C-glycosides  

Microsoft Academic Search

Phase transfer catalysis (PTC) has been used for the synthesis of anomeric glycosyl derivatives, which included O-, S-, Se- and C- glycosides. These various glycosyl derivatives have been stereospecifically obtained from glycosyl halides 1, 2, 3, 14, 26. These reactions proceeded in generally good yields, and were essentially complete within 3 h.

D. Carrière; S. J. Meunier; F. D. Tropper; S. Cao; R. Roy

2000-01-01

290

Disposition and metabolism of the antitumor glycoside phyllanthoside in mouse and beagle dog  

Microsoft Academic Search

Phyllanthoside is a naturally occurring glycoside with activity against IP transplantable murine tumors. Phyllanthoside administered IV, to mice at a nontoxic dose of 16 mg\\/kg could not be detected in blood or plasma even 30 s after administration. There was rapid formation of a less polar metabolite, which disappeared with a half-life of about 10 min. When phyllanthoside was administered

David J. Moore; Garth Powis

1986-01-01

291

Initial Optimization of a New Series of ?-Secretase Modulators Derived from a Triterpene Glycoside.  

PubMed

The discovery of a new series of ?-secretase modulators is disclosed. Starting from a triterpene glycoside ?-secretase modulator that gave a very low brain-to-plasma ratio, initial SAR and optimization involved replacement of a pendant sugar with a series of morpholines. This modification led to two compounds with significantly improved central nervous system (CNS) exposure. PMID:24900406

Fuller, Nathan O; Hubbs, Jed L; Austin, Wesley F; Creaser, Steffen P; McKee, Timothy D; Loureiro, Robyn M B; Tate, Barbara; Xia, Weiming; Ives, Jeffrey L; Findeis, Mark A; Bronk, Brian S

2012-11-01

292

Determination of Sterols in Foods: Recovery of Free, Esterified, and Glycosidic Sterols  

Microsoft Academic Search

A reliable method for routine use in the determination of sterols in foods is described. In the sample preparation procedure, acid hydrolysis prior to alkaline saponification was used to liberate glycosidic sterols. Sterols were analyzed by capillary gas chromatography as the trimethylsilyl ether derivatives and quantified using an internal standard (dihydrocholesterol). In method development, the main focus was on optimization

Jari Toivo; Katherine Phillips; Anna-Maija Lampi; Vieno Piironen

2001-01-01

293

Anti-hepatitis B virus activities and absolute configurations of sesquiterpenoid glycosides from Phyllanthus emblica.  

PubMed

During the process exploring anti-viral compounds from Phyllanthus species, eight new highly oxygenated bisabolane sesquiterpenoid glycoside phyllaemblicins G1-G8 () were isolated from Phyllanthus emblica, along with three known compounds, phyllaemblicin F (), phyllaemblic acid () and glochicoccin D (). Phyllaemblicin G2 (), bearing a tricyclo [3.1.1.1] oxygen bridge ring system, is an unusual sesquiterpenoid glycoside, while phyllaemblicins G6-G8 () are dimeric sesquiterpenoid glycosides with two norbisabolane units connecting through a disaccharide. All the structures were elucidated by the extensive analysis of HRMS and NMR data. The relative configuration of phyllaemblicin G2 was constructed based on heteronuclear coupling constants measurement, and the absolute configurations for all new compounds were established by calculated electronic circular dichroism (ECD) using time dependent density functional theory. The sesquiterpenoid glycoside dimers displayed potential anti-hepatitis B virus (HBV) activities, especially for the new compound with IC50 of 8.53 ± 0.97 and 5.68 ± 1.75 ?M towards the HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively. PMID:25268491

Lv, Jun-Jiang; Wang, Ya-Feng; Zhang, Jing-Min; Yu, Shan; Wang, Dong; Zhu, Hong-Tao; Cheng, Rong-Rong; Yang, Chong-Ren; Xu, Min; Zhang, Ying-Jun

2014-10-15

294

Design and synthesis of nuclear localization sequence peptidomimetics utilizing glycoside scaffolding  

E-print Network

that exhibited the most effective inhibition in the competition assay. The functional handle would serve as a linker for conjugating the tetra-aminopropyl glycosides to a non-import active protein. In this way it would be possible to determine conclusively...

Schiller, Shawn Earle Richard

2012-06-07

295

The flavonoid glycosides and procyanidin composition of Deglet Noor dates (Phoenix dactylifera).  

PubMed

The fruits of the date palm (Phoenix dactylifera) are consumed throughout the world and are an important part of the diet in the Middle East. Dates at the rutab and tamar maturity and ripening stages contain a wide array of phenolic antioxidants, but little is known about the composition of phenolic compounds in dates at the khalal stage of ripening. In the current study, the flavonoid glycoside and procyanidin compositions of dates of the cultivar Deglet Noor harvested at the khalal stage of maturity were characterized using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI/MS/MS). Procyanidin oligomers through decamers were identified in extracts of these dates. Higher molecular weight polymers, undecamers through heptadecamers, were also apparent from mass spectra. Thirteen flavonoid glycosides of luteolin, quercetin, and apigenin, 19 when considering isomeric forms, were also identified. Mass spectra indicate that both methylated and sulfated forms of luteolin and quercetin are present as mono-, di-, and triglycosylated conjugates whereas apigenin is present as only the diglycoside. LC-ESI/MS/MS spectra indicate that quercetin and luteolin formed primarily O-glycosidic linkages whereas apigenin is present as the C-glycoside. PMID:16536626

Hong, Yun Jeong; Tomas-Barberan, F A; Kader, Adel A; Mitchell, Alyson E

2006-03-22

296

Utilisation of steviol glycosides from Stevia rebaudiana (Bertoni) by lactobacilli and bifidobacteria in in vitro conditions.  

PubMed

In the current study, eight strains of bifidobacteria and seven strains of lactobacilli were tested for their ability to grow in the presence of rebaudioside A and steviol glycosides from the sweetener Natusweet M001 originating from herb Stevia rebaudiana (Bertoni). Stevia is gaining popularity as a natural, non-caloric sugar substitute, and recently, it was allowed as a food additive by European Union too. Utilisation of steviol glycosides by intestinal microbiota suggests that they might have potential prebiotic effect. Based on the evaluation of bacterial density and pH values in our in vitro study, it was found that lactobacilli and bifidobacteria tested were able to utilise steviol glycosides as a carbon source only to a very limited extent. All strains tested showed significantly lower change in the absorbance A540 (P?glycosides. PMID:24249153

Kunová, Gabriela; Rada, Vojt?ch; Vidaillac, Adrien; Lisova, Ivana

2014-05-01

297

Lesson 46: Reversives  

E-print Network

] [resurrect] [abort] [praise] [reprimand] B). Utanzu wa kufanya au kulinyambua neon [reversed meaning nguo. [Mother is arranging the clothes.] Mama anapangua nguo. [Mother is disarranging the clothes.] 3

298

Glycoside hydrolases as components of putative carbohydrate biosensor proteins in Clostridium thermocellum.  

PubMed

The composition of the cellulase system in the cellulosome-producing bacterium, Clostridium thermocellum, has been reported to change in response to growth on different carbon sources. Recently, an extensive carbohydrate-sensing mechanism, purported to regulate the activation of genes coding for polysaccharide-degrading enzymes, was suggested. In this system, CBM modules, comprising extracellular components of RsgI-like anti-? factors, were proposed to function as carbohydrate sensors, through which a set of cellulose utilization genes are activated by the associated ?(I)-like factors. An extracellular module of one of these RsgI-like proteins (Cthe_2119) was annotated as a family 10 glycoside hydrolase, RsgI6-GH10, and a second putative anti-? factor (Cthe_1471), related in sequence to Rsi24, was found to contain a module that resembles a family 5 glycoside hydrolase (termed herein Rsi24C-GH5). The present study examines the relevance of these two glycoside hydrolases as sensors in this signal-transmission system. The RsgI6-GH10 was found to bind xylan matrices but exhibited low enzymatic activity on this substrate. In addition, this glycoside hydrolase module was shown to interact with crystalline cellulose although no hydrolytic activity was detected on cellulosic substrates. Bioinformatic analysis of the Rsi24C-GH5 showed a glutamate-to-glutamine substitution that would presumably preclude catalytic activity. Indeed, the recombinant module was shown to bind to cellulose, but showed no hydrolytic activity. These observations suggest that these two glycoside hydrolases underwent an evolutionary adaptation to function as polysaccharide binding agents rather than enzymatic components and thus serve in the capacity of extracellular carbohydrate sensors. PMID:20820855

Bahari, Liat; Gilad, Yuval; Borovok, Ilya; Kahel-Raifer, Hamutal; Dassa, Bareket; Nataf, Yakir; Shoham, Yuval; Lamed, Raphael; Bayer, Edward A

2011-07-01

299

Supplementing with non-glycoside hydrolase proteins enhances enzymatic deconstruction of plant biomass.  

PubMed

The glycoside hydrolases (GH) of Caldicellulosiruptor bescii are thermophilic enzymes, and therefore they can hydrolyze plant cell wall polysaccharides at high temperatures. Analyses of two C. bescii glycoside hydrolases, CbCelA-TM1 and CbXyn10A with cellulase and endoxylanase activity, respectively, demonstrated that each enzyme is highly thermostable under static incubation at 70°C. Both enzymes, however, rapidly lost their enzymatic activities when incubated at 70°C with end-over-end shaking. Since crowding conditions, even at low protein concentrations, seem to influence enzymatic properties, three non-glycoside hydrolase proteins were tested for their capacity to stabilize the thermophilic proteins at high temperatures. The three proteins investigated were a small heat shock protein CbHsp18 from C. bescii, a histone MkHistone1 from Methanopyrus kandleri, and bovine RNase A, from a commercial source. Fascinatingly, each of these proteins increased the thermostability of the glycoside hydrolases at 70°C during end-over-end shaking incubation, and this property translated into increases in hydrolysis of several substrates including the bioenergy feedstock Miscanthus. Furthermore, MkHistone1 and RNase A also altered the initial products released from the cello-oligosaccharide cellopentaose during hydrolysis with the cellodextrinase CbCdx1A, which further demonstrated the capacity of the three non-GH proteins to influence hydrolysis of substrates by the thermophilic glycoside hydrolases. The non-GH proteins used in the present report were small proteins derived from each of the three lineages of life, and therefore expand the space from which different polypeptides can be tested for their influence on plant cell wall hydrolysis, a critical step in the emerging biofuel industry. PMID:22952777

Su, Xiaoyun; Zhang, Jing; Mackie, Roderick I; Cann, Isaac K O

2012-01-01

300

Ultrasonic Time Reversal Mirrors  

NASA Astrophysics Data System (ADS)

For more than ten years, time reversal techniques have been developed in many different fields of applications including detection of defects in solids, underwater acoustics, room acoustics and also ultrasound medical imaging and therapy. The essential property that makes time reversed acoustics possible is that the underlying physical process of wave propagation would be unchanged if time were reversed. In a non dissipative medium, the equations governing the waves guarantee that for every burst of sound that diverges from a source there exists in theory a set of waves that would precisely retrace the path of the sound back to the source. If the source is pointlike, this allows focusing back on the source whatever the medium complexity. For this reason, time reversal represents a very powerful adaptive focusing technique for complex media. The generation of this reconverging wave can be achieved by using Time Reversal Mirrors (TRM). It is made of arrays of ultrasonic reversible piezoelectric transducers that can record the wavefield coming from the sources and send back its time-reversed version in the medium. It relies on the use of fully programmable multi-channel electronics. In this paper we present some applications of iterative time reversal mirrors to target detection in medical applications.

Fink, Mathias; Montaldo, Gabriel; Tanter, Mickael

2004-11-01

301

Reversibility of laser filamentation  

E-print Network

We investigate the reversibility of laser filamentation, a self-sustained, non-linear propagation regime including dissipation and time-retarded effects. We show that even losses related to ionization marginally affect the possibility of reverse propagating ultrashort pulses back to the initial conditions, although they make it prone to finite-distance blow-up susceptible to prevent backward propagation.

Nicolas Berti; Wahb Ettoumi; Jérôme Kasparian; Jean-Pierre Wolf

2014-01-13

302

Geomagnetism II: Magnetic Reversals  

NSDL National Science Digital Library

This is an activity about the periodic reversals of Earth's magnetic field. Learners will graph the frequency of magnetic pole reversals over the past 800,000 years and investigate answers to questions using the graphed data. This is Activity 8 in the Exploring Magnetism on Earth teachers guide.

303

A new glycoside, 3-O-demethylcolchicine-3-O-alpha-d-glucopyranoside, from Gloriosa superba seeds.  

PubMed

A new colchicine glycoside, 3-O-demethylcolchicine-3-O-alpha-D-glucopyranoside, has been isolated from Gloriosa superba seeds. The assigned structure has been corroborated by spectroscopic data and enzymatic hydrolysis. PMID:11833615

Suri, O P; Gupta, B D; Suri, K A; Sharma, A K; Satti, N K

2001-01-01

304

Identification and quantitation of glycosidically bound aroma compounds in three tobacco types by gas chromatography-mass spectrometry.  

PubMed

Glycosidically bound aroma compounds in three different types of tobacco were investigated. After isolation of extracts obtained by Amberlite XAD-2 adsorption and ethyl acetate elution, glycosides were analyzed after enzymatic hydrolysis by gas chromatography-mass spectrometry (GC-MS) or directly after trifluoroacetylated (TFA) derivatization by GC-MS in electron ionization (EI) and negative chemical ionization (NCI) mode. In total 21 bound aglycones were identified by ?-glucosidase hydrolysis. These aglycones mainly consisted of C13-norisoprenoids, aromatic components and sesquiterpenoids. Additionally, with the aid of enzymatic hydrolysis, 15 ?-d-glucopyranosides and 1 ?-d-rutinoside were tentatively identified by TFA derivatization. TFA method was validated by repeatability and successfully employed to analyze different types of tobacco. Principal component analysis (PCA) was carried out on identified glycoside variables to visualize the difference between the tobacco types and the relationship between the glycoside variables and the tobacco types was established. PMID:24011421

Cai, Kai; Xiang, Zhangmin; Pan, Wenjie; Zhao, Huina; Ren, Zhu; Lei, Bo; Geng, Zhaoliang

2013-10-11

305

PREPARATIVE SEPARATION AND PURIFICATION OF FOUR PHENYLPROPANOID GLYCOSIDES FROMRHODIOLA ROSEA BY HIGH-SPEED COUNTER-CURRENT CHROMATOGRAPHY  

Microsoft Academic Search

Phenylpropanoid glycosides are a class of the major bioactive components from Rhodiola rosea. In this study, an efficient method for isolation and purification of four phenylpropanoid glycosides (PPGS) from Rhodiola rosea was established by High-speed Counter-current Chromatography (HSCCC). Rhodiola rosea extract was pre-separated by HPD-200 macroporous resin and polyamide column adsorption chromatography for the enrichment of PPGS and the removal

Chaoyang Ma; Liming Hu; Zaixiang Lou; Hongxin Wang; Xiaohong Gu

2012-01-01

306

Secondary chemistry of hybrid and parental willows: Phenolic glycosides and condensed tannins in Salix sericea, S. eriocephala , and their hybrids  

Microsoft Academic Search

Salix sericea andS. eriocephala differ markedly in secondary chemistry.S. sericea produces phenolic glycosides, salicortin and 2?-cinnamoylsalicortin, and low concentrations of condensed tannin. In contrast,S. eriocephala produces no phenolic glycosides, but high concentrations of condensed tannins. Hybrid chemistry is intermediate for both types of chemicals, suggesting predominantly additive inheritance of these two defensive chemical systems from the parental species. However, there

Colin M. Orians; Robert S. Fritz

1995-01-01

307

["Reversible" dementia in 2011].  

PubMed

Reversible dementias are rare and account for approximately 1.5% of all dementias. The most frequent etiology is represented by neurosurgical causes such as benign tumours, adult chronic hydrocephalus (so-called « normal pressure » hydrocephalus) or subdural hematoma, which are easily revealed by neuroimaging. Systematic ancillary investigations aimed at detecting an infectious disease (syphilis, HIV infection, Lyme neuroborreliosis or, more rarely, Whipple disease), an endocrine aetiology or a vitamin deficiency are rarely contributory, but remain relevant since these dementias could be reversible. Discovering a reversible cause of dementia does not always allow full recovery after treatment. However, systematic ancillary investigations can identify and treat concomitant reversible conditions, which contribute to worsening the main clinical condition in nearly 25% of dementia cases. PMID:21690030

Michel, Jean-Marc; Sellal, François

2011-06-01

308

Reversing the arms race  

SciTech Connect

This paper contains proceedings of Reversing The Arms Race. Topics covered include: Verifying Reductions of Nuclear Warheads; Verifying Limits on Nuclear-Armed Cruise Missiles; and The Technical Basis for Warhead Detection.

von Hippel, F. (Princeton Univ., NJ (United States)); Sagdeev, R.Z. (Space Research Inst., Moscow (USSR))

1992-01-01

309

Reverse Osmosis Membrane.  

National Technical Information Service (NTIS)

The patent application describes the preparation of a reverse osmosis membrane by reaction of a film or layer of polyethylenimine with a polyfunctional reagent whose functional groups are capable of reacting with amine groups. The polyfunctional reagent i...

J. E. Cadotte

1975-01-01

310

All Skate, Now Reverse  

E-print Network

All Skate, Now Reverse is a memoir that consists of personal narratives that are set in or are about my growing up in Nebraska. It is about life and its defining moments, and the collection summons up childhood epiphanies ...

Glover, Angela l.

2008-07-28

311

Reverse Transcription-PCR  

NSDL National Science Digital Library

This Flash animation shows how the method of reverse transcription-PCR is performed and some sample data are produced. It uses sound and mouse-over identification to help students learn more and retain the information.

American Society For Microbiology;

2003-05-12

312

Acylated delphinidin glycosides from violet and violet-blue flowers of Clematis cultivars and their coloration.  

PubMed

Three new acylated delphinidin glycosides, delphinidin 3-O-beta-[(2"-trans-caffeoylglucopyranosyl)-(1 --> 2)-(6"-succinylgalactopyranoside)]-7-O-beta-glucopyranoside (1), delphinidin 3-O-beta-[(2"-trans-caffeoylglucopyranosyl)-(1 --> 2)-(6"-trans-caffeoyl-tartaroyl-malonylgalactopyranoside)]-7-O-beta-glucopyranoside (2), and delphinidin 3-O-beta-[(2"-trans-caffeoylglucopyranosyl)-(1 --> 2)-(6"-trans-caffeoyl-tartaroyl-malonylgalactopyranoside)]-3'-O-beta-glucuronopyranoside (3), were isolated from the violet and violet-blue sepals of Clematis cultivars 'Jackmanii Superba' and 'Fujimusume'. The chemical structures of the isolated anthocyanins were determined by LC-MS, characterization of hydrolyzates, and UV, 1H and 13C NMR spectroscopy. The visible absorption spectra of these anthocyanins were compared with those of fresh sepals and crude extracts in pH 5.1 buffer solution. In addition, the co-pigment effect with some kaempferol glycosides and caffeoylglucose was examined. PMID:24427942

Sakaguchi, Keisuke; Kitajima, Junichi; Iwashina, Tsukasa

2013-11-01

313

Hydrolysis of glycosidically bound flavour compounds from oak wood by Oenococcus oeni.  

PubMed

Malolactic fermentation (MLF), which is conducted by lactic acid bacteria (LAB), has a significant influence on the stability and organoleptic quality of wine. Recent studies have shown that when MLF is carried out in oak wood barrels, LAB were also able to interact with wood and increase volatile compound contents such as vanillin during MLF. The release of these compounds indicates that LAB may convert vanillin precursors present in oak wood. In this work, the effect of commercial glycosidases on the released vanillin was firstly studied. This aldehyde is present in wood extracts in monoglycosidic forms where the major glycones are arabinose and xylose. Other aglycons released during MLF in barrels, syringaldehyde and whisky-lactones, can be considered as other sources of aroma. Secondly, strains selected with high activities toward glycoside substrates could hydrolyse vanillin glycoside precursors from oak wood with the same efficiency as commercial enzymes. PMID:17993382

Bloem, Audrey; Lonvaud-Funel, Aline; de Revel, Gilles

2008-02-01

314

Preparation and evaluation of technetium-99m labeled cardiac glycoside derivatives as potential myocardial imaging agent.  

PubMed

Three cardiac glycosides, two natural, cymarin and convallotoxin and one synthetic, strophanthidin-beta-D-glucoside were converted to their thiosemicarbazone and subsequently radiolabeled with 99mTc by chelation. The resulting radioactive chelate complexes were evaluated in animals to determine the suitability of this class of compounds for myocardial imaging. It was observed from the animal biodistribution data of the three radioactive compounds, there was a considerable variation in the heart to non-target organ uptake ratio. A possible explanation of this variation was offered in the light of their lipophilic character, protein binding ability and affinity towards non-target receptors. It is anticipated that this study may help to develop a 99mTc-cardiac glycoside complex with better distribution characteristics, and such a compound may offer a suitable alternative to 201Tl, which is at present used for myocardial imaging. PMID:3255737

Misra, M; Sarkar, H S; Chatterjee, M; Banerjee, S

1988-01-01

315

Relationships between chemical structures and functions of triterpene glycosides isolated from sea cucumbers  

PubMed Central

Many marine triterpene glycosides have in vitro and in vivo activities with very low toxicity, suggesting that they are suitable agents for the prevention and treatment of different diseases, particularly cancer. However, the molecular mechanisms of action of natural marine compounds in cancer, immune, and other various cells are not fully known. This review focuses on the structural characteristics of marine triterpene glycosides and how these affect their biological activities and molecular mechanisms. In particular, the membranotropic and membranolytic activities of frondoside A and cucumariosides from sea cucumbers and their ability to induce cytotoxicity and apoptosis have been discussed, with a focus on structure-activity relationships. In addition, the structural characteristics and antitumor effects of stichoposide C and stichoposide D have been reviewed along with underlying their molecular mechanisms. PMID:25250309

Park, Joo-In; Bae, Hae-Rahn; Kim, Chang Gun; Stonik, Valentin A.; Kwak, Jong-Young

2014-01-01

316

Structures of the novel ?-glucosyl linked diterpene glycosides from Stevia rebaudiana.  

PubMed

From the commercial extract of the leaves of Stevia rebaudiana, two new minor diterpene glycosides having ?-glucosyl linkage were isolated besides the known steviol glycosides including stevioside, steviolbioside, rebaudiosides A-F, rubusoside and dulcoside A. The structures of the two compounds were identified as 13-[(2-O-(3-?-O-d-glucopyranosyl)-?-d-glucopyranosyl-3-O-?-d-glucopyranosyl-?-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid ?-d-glucopyranosyl ester (1), and 13-[(2-O-?-d-glucopyranosyl-3-O-(4-O-?-d-glucopyranosyl)-?-d-glucopyranosyl-?-d-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid ?-d-glucopyranosyl ester (2), on the basis of extensive NMR and MS spectral data as well as chemical studies. PMID:21798525

Chaturvedula, Venkata Sai Prakash; Upreti, Mani; Prakash, Indra

2011-09-27

317

Synthetic study on the relationship between structure and sweet taste properties of steviol glycosides.  

PubMed

The structure activity relationship between the C??-C?? methylene double bond on the aglycone of steviol glycosides and the corresponding impact on their sweet taste has been reported here for the first time. It has been observed that converting stevioside and rebaudioside A to their corresponding ketones by switching the doubly bonded methylene on C-17 for a ketone group actually removes the sweet taste properties of these molecules completely. Regenerating the original molecules tends to restore the sweet taste of both the steviol glycosides. Thus this C??-C?? methylene double bond in rebaudioside A and stevioside can be regarded as a pharmacophore essential for the sweetness property of these molecules. PMID:22481539

Upreti, Mani; Dubois, Grant; Prakash, Indra

2012-01-01

318

Three new pentasaccharide resin glycosides from the roots of sweet potato (Ipomoea batatas).  

PubMed

Three new pentasaccharide resin glycosides, batatosides III-V (1-3), were isolated from the roots of Sweet potato (Ipomoea batatas). Saponification of the crude resin glycoside mixture yielded substituents and simonic acid B. The structures of the isolated compounds (1-3) were established through spectroscopic analyses, including high field NMR spectroscopy and HR-ESI-MS, and chemical correlation. The major characteristics of 3 are the presence of three different substituents, especially the substituent of cinnamic acid was seldom. The monosaccharides of 1-3 were proved by GC-MS and the absolute configuration of aglycone was further established as S by Mosher's method with R-methyloxyphenylacetic acid (MPA) and S-MPA. PMID:19043237

Yin, Yong-Qin; Huang, Xue-Feng; Kong, Ling-Yi; Niwa, Masatake

2008-12-01

319

Synthesis of thymol glycosides under SCCO2 conditions using amyloglucosidase from Rhizopus mold.  

PubMed

Enzymatic synthesis of water soluble thymol glycosides were carried out using amyloglucosidase from Rhizopus mold under supercritical carbon dioxide (SCCO2) conditions of 120 bar pressure at 50 °C. Thymol 1 formed glycosides with D-galactose 2, D-mannose 3, D-fructose 4, D-ribose 5 and D-arabinose 6 in yields ranging from 20.6% to 54.2%. Spectral characterization studies revealed that the reaction occurred between the phenolic OH group of thymol and 1-O/2-O groups of D-fructose and C-1 group of D-galactose, D-mannose, D-ribose and D-arabinose resulting in monoglycosylated/arylated derivatives. PMID:24425985

Kumar, Tiruppur Venkatachallam Suresh; Sankar, Kadimi-Udaya; Divakar, Soundar

2013-08-01

320

Simultaneous determination of steviol and steviol glycosides by liquid chromatography-mass spectrometry.  

PubMed

A direct, versatile method for the determination of steviol and nine steviol glycosides in food products has been developed by using electrospray ionisation liquid chromatography-mass spectrometry in the negative-ion mode. Ten stevia compounds were readily separated on an amino column by using a gradient separation. Data for analyte quantification were collected in the selected ion monitoring mode, giving the method limit of detection of 0.01-0.34 µg g?¹ and repeatability at the limit of quantitation of 2%-15% relative standard deviation. Thirty-four commercially available food products were tested by using the optimised method, and in these products rebaudioside A and stevioside comprised 52%-100% of the total steviol glycosides. Multiple reaction monitoring data were collected to provide analyte confirmation. Stability data for rebaudioside A stored at room temperature, 40°C and 60°C over a period of 1-14 days are shown. PMID:23050630

Shah, Romina; De Jager, Lowri S; Begley, Timothy H

2012-01-01

321

Pregnane Glycosides Interfere With Steroidogenic Enzymes to Down-Regulate Corticosteroid Production in Human Adrenocortical H295R Cells  

PubMed Central

A group of bioactive steroidal glycosides (pregnanes) with anorectic activity in animals was isolated from several genera of milkweeds including Hoodia and Asclepias. In this study, we investigated the effects, structure-activity relationships, and mechanism of action of pregnane glycosides on steroidogenesis in human adrenocortical H295R cells. Administration of pregnane glycosides for 24 h suppressed the basal and forskolin-stimulated release of androstenedione, corticosterone, and cortisone from H295R cells. The conversion of progesterone to 11-deoxycorticosterone and 17-hydroxyprogesterone to either androstenedione or 11-deoxycortisol was most strongly affected, with 12-cinnamoyl-, benzoyl-, and tigloyl-containing pregnanes showing the highest activity. Incubation of pregnane glycosides for 24 h had no effect on mRNA transcripts of CYP11A1, CYP21A1, CYP11B1 cytochrome enzymes and steroidogenic acute regulatory protein (StaR) protein, yet resulted in twofold decrease in HSD3B1 mRNA levels. At the same time, pregnane glycosides had no effect on the CYP1, 2, or 3 drug and steroid metabolism enzymes and showed weak Na+/K+ ATPase and glucocorticoid receptor binding. Taken together, these data suggest that pregnane glycosides specifically suppress steroidogenesis through strong inhibition of 11?-hydroxylase and steroid 17-alpha-monooxygenase, and weak inhibition of cytochrome P450 side chain cleavage enzyme and 21?-hydroxylase, but not 3?-hydroxysteroid dehydrogenase/isomerase. PMID:23065845

KOMARNYTSKY, SLAVKO; ESPOSITO, DEBORA; POULEV, ALEXANDER; RASKIN, ILYA

2013-01-01

322

Pregnane glycosides interfere with steroidogenic enzymes to down-regulate corticosteroid production in human adrenocortical H295R cells.  

PubMed

A group of bioactive steroidal glycosides (pregnanes) with anorectic activity in animals was isolated from several genera of milkweeds including Hoodia and Asclepias. In this study, we investigated the effects, structure-activity relationships, and mechanism of action of pregnane glycosides on steroidogenesis in human adrenocortical H295R cells. Administration of pregnane glycosides for 24 h suppressed the basal and forskolin-stimulated release of androstenedione, corticosterone, and cortisone from H295R cells. The conversion of progesterone to 11-deoxycorticosterone and 17-hydroxyprogesterone to either androstenedione or 11-deoxycortisol was most strongly affected, with 12-cinnamoyl-, benzoyl-, and tigloyl-containing pregnanes showing the highest activity. Incubation of pregnane glycosides for 24 h had no effect on mRNA transcripts of CYP11A1, CYP21A1, CYP11B1 cytochrome enzymes and steroidogenic acute regulatory protein (StaR) protein, yet resulted in twofold decrease in HSD3B1 mRNA levels. At the same time, pregnane glycosides had no effect on the CYP1, 2, or 3 drug and steroid metabolism enzymes and showed weak Na(+) /K(+) ATPase and glucocorticoid receptor binding. Taken together, these data suggest that pregnane glycosides specifically suppress steroidogenesis through strong inhibition of 11?-hydroxylase and steroid 17-alpha-monooxygenase, and weak inhibition of cytochrome P450 side chain cleavage enzyme and 21?-hydroxylase, but not 3?-hydroxysteroid dehydrogenase/isomerase. PMID:23065845

Komarnytsky, Slavko; Esposito, Debora; Poulev, Alexander; Raskin, Ilya

2013-05-01

323

Reversible logic circuit synthesis  

Microsoft Academic Search

Reversible or information-lossless circuits have applications in digital signal processing, communication, computer graphics and cryptography. They are also a fundamental requirement in the emerging field of quantum computation. We investigate the synthesis of reversible circuits that employ a minimum number of gates and contain no redundant input-output line-pairs (temporary storage channels). We prove constructively that every even permutation can be

Vivek V. Shende; Aditya K. Prasad; I. L. Markov; J. P. Hayes

2002-01-01

324

Reversibility of antibiotic resistance  

PubMed Central

Although theoretically attractive, the reversibility of resistance has proven difficult in practice, even though antibiotic resistance mechanisms induce a fitness cost to the bacterium. Associated resistance to other antibiotics and compensatory mutations seem to ameliorate the effect of antibiotic interventions in the community. In this paper the current understanding of the concepts of reversibility of antibiotic resistance and the interventions performed in hospitals and in the community are reviewed. PMID:24836051

2014-01-01

325

On thermodynamic and microscopic reversibility  

SciTech Connect

The word 'reversible' has two (apparently) distinct applications in statistical thermodynamics. A thermodynamically reversible process indicates an experimental protocol for which the entropy change is zero, whereas the principle of microscopic reversibility asserts that the probability of any trajectory of a system through phase space equals that of the time reversed trajectory. However, these two terms are actually synonymous: a thermodynamically reversible process is microscopically reversible, and vice versa.

Crooks, Gavin E.

2011-07-12

326

Cytotoxic 16-?-[( d-xylopyranosyl)oxy]oxohexadecanyl triterpene glycosides from a Malagasy plant, Physena sessiliflora  

Microsoft Academic Search

Brine shrimp lethality assay-guided separation of the MeOH extract of leaves of Physena sessiliflora, which is endemic to Madagascar, afforded eight triterpene glycosides, Physenoside S1–4 and 16-?-[(d-xylopyranosyl)oxy]oxohexadecanyl homologues, Physenoside S5–8. Structural elucidation of these compounds was based on both spectroscopic analyses and chemical properties. Physenoside S7 and S8 have significant cytotoxic activities in the brine shrimp lethality assay.

Masaki Inoue; Kazuhiro Ohtani; Ryoji Kasai; Mayu Okukubo; Marta Andriantsiferana; Kazuo Yamasaki; Tohru Koike

2009-01-01

327

Cardiotonic glycosides from biomass of Digitalis purpurea L. cultured in temporary immersion systems  

Microsoft Academic Search

Cardiotonic glycosides are extracted mostly from leaves of Digitalis plants. Commercial production of bioactive secondary metabolites by traditional agriculture is an inefficient process and\\u000a can be affected by climatic and soil conditions. Strategies, based on in vitro culture methods, have been extensively studied\\u000a to improve the production of specific plant derived chemicals. The aim of the present research was to

Naivy Pérez-Alonso; Dirk Wilken; André Gerth; Annett Jähn; Horst-Michael Nitzsche; Gerhard Kerns; Alina Capote-Perez; Elio Jiménez

2009-01-01

328

Human skeletal muscle digitalis glycoside receptors (Na,K-ATPase)—Importance during digitalization  

Microsoft Academic Search

The aims of the present study were to evaluate in humans the putative importance of skeletal muscle digitalis glycoside receptors (Na,K-ATPase) in the volume of distribution of digoxin and to assess whether therapeutic digoxin exposure might cause digitalis receptor upregulation in skeletal muscle. Samples of the vastus lateralis were obtained postmortem from 11 long-term (9 months to 9 years) digitalized

Thomas Andersen Schmidt; Peter Holm-Nielsen; Keld Kjeldsen

1993-01-01

329

Pharmacokinetics of Loganin in rat plasma after oral administration of total glycosides of Jinkuishenqi pill  

Microsoft Academic Search

To investigate the pharmacokinetics of loganin in rat plasma which is administered total glycoside (TG) of Jinkuishenqi pill with three different doses and the influence of verapamil. The three different doses (2.95 4.43 5.90 gmiddotkg-1)of TG alone or TG(5.90 gmiddotkg-1) in combination with verapamil (10 mgmiddotkg-1) was administered to Wistar rats. Serial blood samples of loganin were measured by RP-HPLC.

Wen-lan Li; Juan Du; Yu-bin Ji; Zhi Sun; Xiang-ming Sun

2009-01-01

330

Two novel steroidal alkaloid glycosides from the seeds of Lycium barbarum.  

PubMed

Two novel steroidal alkaloid glycosides, lycioside A (1) and lycioside B (2) were isolated from the seeds of Lycium barbarum. Their structures were determined by various spectroscopic analyses. Compounds 1 and 2 showed inhibitory activities with the IC(50) values of 75.3 and 72.8 ?M against rat intestinal sucrase, and 63.4 and 59.1 ?M against rat intestinal maltase. PMID:22162165

Wang, Kun; Sasaki, Tatsunori; Li, Wei; Li, Qin; Wang, Yinghua; Asada, Yoshihisa; Kato, Hiroyoshi; Koike, Kazuo

2011-12-01

331

Synthesis of Pro-Xylane TM: A new biologically active C-glycoside in aqueous media  

Microsoft Academic Search

The scope and limitation of Lubineau’s reaction were evaluated for the synthesis of C-glycosides (compounds 1–13). Further transformation of side chain carbonyl was also achieved (compounds 16–23). Optimization of these two steps was investigated in xylose case. Some of the compounds were shown to stimulate sulfated glycosaminoglycans (GAGs) synthesis. Compound 20 (called Pro-XylaneTM) was identified as the best activator of

Alexandre Cavezza; Christophe Boulle; Amélie Guéguiniat; Patrick Pichaud; Simon Trouille; Louis Ricard; Maria Dalko-Csiba

2009-01-01

332

Production of Hesperetin Glycosides by Xanthomonas campestris and Cyclodextrin Glucanotransferase and Their Anti-allergic Activities  

PubMed Central

The production of hesperetin glycosides was investigated using glycosylation with Xanthomonas campestris and cyclodextrin glucanotransferase (CGTase). X. campestris glucosylated hesperetin to its 3'-, 5-, and 7-O-glucosides, and CGTase converted hesperetin glucosides into the corresponding maltosides. The resulting 7-O-glucoside and 7-O-maltoside of hesperetin showed inhibitory effects on IgE antibody production and on O2- generation from rat neutrophils. PMID:22254014

Shimoda, Kei; Hamada, Hiroki

2010-01-01

333

Rapid Separation and Determination of Four Phenylpropanoid Glycosides from T. chamaedrys by Capillary Electrophoresis Method  

Microsoft Academic Search

Summary A new capillary electrophoresis method was developed for the separation of four phenylpropanoid glycosides (teucrioside, verbascoside, teucrioside-3””- O-methyl ether and teucrioside-3””, 4””- O-dimethyl ether) from T. chamaedrys. The electrophoretic separation was performed using a 50 cm × 50 µm i.d. (41.5 cm effective length) fused silica capillary. A phosphate-borate buffer (pH 8.9) in 15% ( v\\/v) isopropanol was used

B. Avula; R. B. Manyam; E. Bedir; I. A. Khan

2003-01-01

334

Effects of verbascoside, a phenylpropanoid glycoside from lemon verbena, on phospholipid model membranes  

Microsoft Academic Search

Phenylpropanoid glycosides are water-soluble compounds widely distributed, most of them deriving from medicinal herbs. Among them, verbascoside or acteoside has exhibited a wide biological activity, being free radical scavenging the most representative one. Moreover, antitumor, antimicrobial, anti-inflammatory, anti-thrombotic and wound healing properties have been previously described. Herein, the interaction of verbascoside with phospholipid membranes has been studied by means of

Lorena Funes; Olga Laporta; Manuela Cerdán-Calero; Vicente Micol

2010-01-01

335

Fast repair of thymine-hydroxyl radical adduct by phenylpropanoid glycosides  

Microsoft Academic Search

The repair effect on thymine-hydroxyl adduct by phenylpropanoid glycosides (PPG): verbascoside, and pedicularioside A, isolated from Pedicularis, were studied using pulse radiolysis technique. From the analysis of transient absorption spectra, the rapid electron transfer from PPG to T-OH? was observed. Phenoxyl radical of PPG were generated via one-electron-transfer reaction. This result showed that two PPG exhibited repair activities on oxidizing

Wenyan Li; Zhihua Zou; Rongliang Zheng; Changzeng Wang; Zhongjian Jia; Side Yao; Nianyun Lin

1997-01-01

336

Isolation and characterization of cytotoxic and antibacterial tetrasaccharide glycosides from Ipomoea stans.  

PubMed

Three new tetrasaccharide glycosides, differing from one reported previously in the type of short-chain fatty acids ester-linked to the tetrasaccharide core, have been isolated and identified from an oligosaccharide fraction of Ipomea stans. Preliminary screening tests showed that the fraction containing these compounds had pronounced cytotoxicity towards three human tumor cell lines as well as specific antibiotic activity against two bacterial strains. PMID:8594150

Reynolds, W F; Yu, M; Enriquez, R G; Gonzalez, H; Leon, I; Magos, G; Villareal, M L

1995-11-01

337

Resin glycoside constituents of Ipomoea pes-caprae (beach morning glory).  

PubMed

Eight new resin glycosides, pescapreins X-XVII (1-8), were isolated from a lipophilic fraction of an ethanol extract of the entire plant of beach morning glory, Ipomoea pes-caprae. Their structures were elucidated by spectroscopic data analysis and by chemical transformation. These compounds were evaluated biologically in terms of cancer cell line cytotoxicity, antibacterial and antifungal activity, and effects on the mu-opioid receptor. PMID:19061389

Tao, Hongwen; Hao, Xiaojiang; Liu, Jinggen; Ding, Jian; Fang, Yuchun; Gu, Qianqun; Zhu, Weiming

2008-12-01

338

Subchronic treatment with vanadate does not potentiate the toxicity of cardiac glycosides  

Microsoft Academic Search

Since it has been claimed that vanadate is an endogenous regulator of Na\\/K-ATPase activity and that it potentiates the toxicity\\u000a of cardiac glycosides, we were alarmed to discover that certain Finnish physicians were prescribing vanadate in combination\\u000a with other trace minerals to elderly patients for many different chronic diseases (e.g., cancer, rheumatism). To study the\\u000a interaction of vanadate and cardiac

E. MacDonald; H. Lihtamo; Kaisa Hellevuo; H. Komulainen

1988-01-01

339

Euphydryas anicia (Lepidoptera: Nymphalidae) utilization of iridoid glycosides from Castilleja and Besseya (Scrophulariaceae) host plants  

Microsoft Academic Search

Iridoid glycosides were found to be sequestered by natural populations ofEuphydryas anicia after ingestion from the host plantsBesseya alpina, B. plantaginea, andCastilleja integra. Both major iridoids ofB. alpina, cataipol and aucubin, were found in butterfly populations where this was the only host plant. The catalpol-aucubin ratio was higher in the butterflies than in the host plant. AnE. anicia population which

Frank R. Stermitz; Dale R. Gardner; Francois J. Odendaal; Paul R. Ehrlich

1986-01-01

340

Variation in iridoid glycosides in a population of Plantago patagonica Jacq. (Plantaginaceae) in Colorado  

Microsoft Academic Search

Plantago patagonica from plants grown in a greenhouse and from a field population in Boulder, Colorado, were sampled for iridoid glycosides. Both aucubin and catalpol were found in P. patagonica, however, not all individual plants contained detectable amounts of both these compounds. Plants grown in the greenhouse (n=8) contained means of 0.26% (±0.04 S.E.) aucubin and 0.23% (±0.05 S.E.) catalpol,

M. Deane Bowers

1996-01-01

341

beta-Glucosidase inhibitory activities of phenylpropanoid glycosides, vanicoside A and B from Polygonum sachalinense rhizome.  

PubMed

The phenylpropanoid glycosides, vanicoside A and B, isolated from rhizomes of giant knotweed (Polygonum sachalinense) showed beta-glucosidase inhibitory activity, with IC(50) values of 59.8 and 48.3 mug/ml (59.9 and 50.5 muM), respectively. In contrast, p-coumaric acid and ferulic acid, corresponding to phenylpropanoyl moieties of vanicosides, exhibited very little inhibition. PMID:16828242

Kawai, Y; Kumagai, H; Kurihara, H; Yamazaki, K; Sawano, R; Inoue, N

2006-09-01

342

Acid epimerization of 20-keto pregnane glycosides is determined by 2D-NMR spectroscopy  

Microsoft Academic Search

Carbohydrates influence many essential biological events such as apoptosis, differentiation, tumor metastasis, cancer, neurobiology,\\u000a immunology, development, host-pathogen interactions, diabetes, signal transduction, protein folding, and many other contexts.\\u000a We now report on the structure determination of pregnane glycosides isolated from the aerial parts of Ceropegia fusca Bolle (Asclepiadaceae). The observation of cicatrizant, vulnerary and cytostatic activities in some humans and animals

Víctor P. García

2011-01-01

343

Positive effects of cyanogenic glycosides in food plants on larval development of the common blue butterfly.  

PubMed

Cyanogenesis is a widespread chemical defence mechanism in plants against herbivory. However, some specialised herbivores overcome this protection by different behavioural or metabolic mechanisms. In the present study, we investigated the effect of presence or absence of cyanogenic glycosides in birdsfoot trefoil (Lotus corniculatus, Fabaceae) on oviposition behaviour, larval preference, larval development, adult weight and nectar preference of the common blue butterfly (Polyommatus icarus, Lycaenidae). For oviposition behaviour there was a female-specific reaction to cyanogenic glycoside content; i.e. some females preferred to oviposit on cyanogenic over acyanogenic plants, while other females behaved in the opposite way. Freshly hatched larvae did not discriminate between the two plant morphs. Since the two plant morphs differed not only in their content of cyanogenic glycoside, but also in N and water content, we expected these differences to affect larval growth. Contrary to our expectations, larvae feeding on cyanogenic plants showed a faster development and stronger weight gain than larvae feeding on acyanogenic plants. Furthermore, female genotype affected development time, larval and pupal weight of the common blue butterfly. However, most effects detected in the larval phase disappeared for adult weight, indicating compensatory feeding of larvae. Adult butterflies reared on the two cyanogenic glycoside plant morphs did not differ in their nectar preference. But a gender-specific effect was found, where females preferred amino acid-rich nectar while males did not discriminate between the two nectar mimics. The presented results indicate that larvae of the common blue butterfly can metabolise the surplus of N in cyanogenic plants for growth. Additionally, the female-specific behaviour to oviposit preferably on cyanogenic or acyanogenic plant morphs and the female-genotype-specific responses in life history traits indicate the genetic flexibility of this butterfly species and its potential for local adaptation. PMID:18600348

Goverde, Marcel; Bazin, Alain; Kéry, Marc; Shykoff, Jacqui A; Erhardt, Andreas

2008-09-01

344

Effect of exogenous steroid glycosides on cultured cells of potato under oxidative stress  

Microsoft Academic Search

Low doses of furostanol glycosides (FG) were shown to elevate the activity of peroxidases (guaiacol-dependent and ascorbate\\u000a peroxidases) and reduce peroxidation of lipids (POL) below the control level in the cell culture of potato (Solanum tuberosum L.). Under oxidative stress (OS) induced by paraquat, FG protected the cell culture from injury with peroxidase activity\\u000a being high and POL level lower

L. A. Volkova; S. N. Maevskaya; A. B. Burgutin; A. M. Nosov

2007-01-01

345

The flavonoid glycosides of Cornus canadensis L. and its allies in Northwestern North America  

Microsoft Academic Search

Summary The flavonoid glycoside profile ofCornus canadensis L. and its allies in Northwestern North America has been determined; quercetin 3-O-glucoside, 3-O-galactoside, 3-O-sophoroside and 3-O-gentiobioside; kaempferol 3-O-glucoside and 3-O-arabinoside. The discontinuity in distribution pattern of quercetin 3-O-gentiobioside within these taxa, associated with the phytogeography and historical factors affecting plant distribution in this area, indicates a possible polytopic and polychronistic origin of

J. F. Bain; K. E. Denford

1979-01-01

346

A monoterpene glucoside and three megastigmane glycosides from Juniperus communis var. depressa.  

PubMed

A new monoterpene glucoside (1) and three new natural megastigmane glycosides (2-4) were isolated along with a known megastigmane glucoside (5) from twigs with leaves of Juniperus communis var. depressa (Cupressaceae) collected in Oregon, U.S.A., and their structures were determined on the basis of spectral and chemical evidence. In addition, the antibacterial activities of the isolated components against Helicobacter pylori were also investigated. PMID:15997135

Nakanishi, Tsutomu; Iida, Naoki; Inatomi, Yuka; Murata, Hiroko; Inada, Akira; Murata, Jin; Lang, Frank A; Iinuma, Munekazu; Tanaka, Toshiyuki; Sakagami, Yoshikazu

2005-07-01

347

Mesophyll distribution of 'antioxidant' flavonoid glycosides in Ligustrum vulgare leaves under contrasting sunlight irradiance  

PubMed Central

Background and Aims Flavonoids have the potential to serve as antioxidants in addition to their function of UV screening in photoprotective mechanisms. However, flavonoids have long been reported to accumulate mostly in epidermal cells and surface organs in response to high sunlight. Therefore, how leaf flavonoids actually carry out their antioxidant functions is still a matter of debate. Here, the distribution of flavonoids with effective antioxidant properties, i.e. the orthodihydroxy B-ring-substituted quercetin and luteolin glycosides, was investigated in the mesophyll of Ligustrum vulgare leaves acclimated to contrasting sunlight irradiance. Methods In the first experiment, plants were grown at 20 % (shade) or 100% (sun) natural sunlight. Plants were exposed to 100 % sunlight irradiance in the presence or absence of UV wavelengths, in a second experiment. Fluorescence microspectroscopy and multispectral fluorescence microimaging were used in both cross sections and intact leaf pieces to visualize orthodihydroxy B-ring-substituted flavonoids at inter- and intracellular levels. Identification and quantification of individual hydroxycinnamates and flavonoid glycosides were performed via HPLC-DAD. Key Results Quercetin and luteolin derivatives accumulated to a great extent in both the epidermal and mesophyll cells in response to high sunlight. Tissue fluorescence signatures and leaf flavonoid concentrations were strongly related. Monohydroxyflavone glycosides, namely luteolin 4?-O-glucoside and two apigenin 7-O-glycosides were unresponsive to changes in sunlight irradiance. Quercetin and luteolin derivatives accumulated in the vacuoles of mesophyll cells in leaves growing under 100 % natural sunlight in the absence of UV wavelengths. Conclusions The above findings lead to the hypothesis that flavonoids play a key role in countering light-induced oxidative stress, and not only in avoiding the penetration of short solar wavelengths in the leaf. PMID:19633310

Agati, Giovanni; Stefano, Giovanni; Biricolti, Stefano; Tattini, Massimiliano

2009-01-01

348

Two new flavone glycosides from the seeds of Impatiens balsamina L.  

PubMed

Two new flavone glycosides were isolated from the seeds of Impatiens balsamina L. and their structures were determined as quercetin-3-O-[?-L-rhamnose-(1 ? 2)-?-d-glucopyranosyl]-5-O-?-D-glucopyranoside (1), and quercetin-3-O-[(6'''-O-caffeoyl)-?-L-rhamnose-(1 ? 2)-?-D-glucopyranosyl]-5-O-?-D-glucopyranoside (2) on the basis of various spectral and chemical studies. PMID:21128143

Lei, Jing; Qian, Shi-Hui; Jiang, Jian-Qin

2010-12-01

349

Effects of phenylethanoid glycosides from Digitalis purpurea L. on the expression of inducible nitric oxide synthase.  

PubMed

We have isolated four different phenylethanoid glycosides (purpureaside A, desrhamnosyl acteoside, calceolarioside B and plantainoside D) from the leaves of Digitalis purpurea (foxglove). The effects of these glycosides on activator protein-1 (AP-1)-mediated inducible nitric oxide synthase (iNOS) gene expression in the Raw264.7 macrophage cell line have been studied. Of these four glycosides, purpureaside A potently inhibited iNOS induction by lipopolysaccharide (LPS). Increase in iNOS mRNA by LPS was completely suppressed by purpureaside A. Purpureaside A did not significantly affect LPS-inducible nuclear factor-kappaB (NF-kappaB) activation or the nuclear translocation of p65. Moreover, a reporter gene assay using AP-1 specific luciferase reporter revealed that the enhanced activity of AP-1 by LPS was completely abolished in cells treated with purpureaside A. These results demonstrated that purpureaside A inhibited LPS-inducible iNOS expression in macrophages through the suppression of AP-1, but not of NF-kappaB. PMID:15969951

Oh, Jae Wook; Lee, Jeong Yong; Han, Song Hee; Moon, Young Hee; Kim, Yoon Gyoon; Woo, Eun-Rhan; Kang, Keon Wook

2005-07-01

350

Interaction of palytoxin and cardiac glycosides on erythrocyte membrane and (Na+ + K+) ATPase.  

PubMed

Palytoxin (PTX), at extremely low concentrations (0.01-1 nM), caused K+ release from rabbit erythrocytes. Among the various chemical compounds tested, cardiac glycosides potently inhibited the PTX-induced K+ release. The order of inhibitory potency (IC50) was cymarin (0.42 microM) greater than convallatoxin (0.9 microM) greater than ouabain (2.3 microM) greater than digitoxin (88 microM) greater than digoxin (90 microM). Their corresponding aglycones, even at 10 microM, did not inhibit the K+ release, but competitively antagonized the inhibitory effect of the glycosides. All these cardiotonic steroids inhibited the activity of (Na+ + K+)-ATPase prepared from hog cerebral cortex in narrow concentration ranges (IC50 = 0.15-2.4 microM), suggesting that the inhibition of K+ release is not related to their inhibitory potency on the (Na+ + K+)-ATPase activity, and the sugar moiety of cardiac glycosides is involved in the inhibition. On the other hand PTX, at higher concentrations (greater than 0.1 microM), inhibited the (Na+ + K+)-ATPase activity. However, this inhibitory effect of PTX was not antagonized by ouabain. It is suggested that, compared with ouabain, PTX has additional binding site(s) on the (Na+ + K+)-ATPase. PMID:2865137

Ozaki, H; Nagase, H; Urakawa, N

1985-10-15

351

Analysis of the transcriptome of Marsdenia tenacissima discovers putative polyoxypregnane glycoside biosynthetic genes and genetic markers.  

PubMed

Marsdenia tenacissima is a well-known anti-cancer medicinal plant used in traditional Chinese medicine due to bioactive constituents of polyoxypregnane glycosides, such as tenacissosides, marsdenosides and tenacigenosides. Genomic information regarding this plant is very limited, and rare information is available about the biosynthesis of polyoxypregnane glycosides. To facilitate the basic understanding about the polyoxypregnane glycoside biosynthetic pathways, de novo assembling was performed to generate a total of 73,336 contigs and 65,796 unigenes, which represent the first transcriptome of this species. These included 27 unigenes that were involved in steroid biosynthesis and could be related to pregnane backbone biosynthesis. The expression patterns of six unigenes involved in polyoxypregnane biosynthesis were analyzed in leaf and stem tissues by quantitative real time PCR (qRT-PCR) to explore their putative function. Furthermore, a total of 15,295 simple sequence repeats (SSRs) were identified from 11,911 unigenes, of which di-nucleotide motifs were the most abundant. PMID:25128726

Zheng, Kaiyan; Zhang, Guanghui; Jiang, Nihao; Yang, Shengchao; Li, Chao; Meng, Zhengui; Guo, Qiaosheng; Long, Guangqiang

2014-09-01

352

Bidesmoside triterpenoid glycosides from Stauntonia chinensis and relationship to anti-inflammation.  

PubMed

Ten triterpenoid glycosides, yemuoside YM(26-35) (1-9 and 12), were isolated from a traditional Chinese medicine known as "Ye Mu Gua" (Stauntonia chinensis DC.) along with two known ones, kalopanax saponin C (10) and sieboldianoside A (11). Their structures, as elucidated by spectroscopic analyses and chemical methods, were either penta-saccharidic or hexa-saccharidic bidesmoside triterpenoid glycosides. To help explain the clinical applications of "Ye Mu Gua" for its anti-inflammatory effects, the inhibitory activity on the release of inflammatory mediators (nitric oxide, TNF-alpha and IL-6) of 1-12 and the related aglycone, hederagenin (13), was evaluated in vitro. It was found that compound 13, but not 1-12, exhibited significant inhibitory activity. The abundant triterpenoid glycosides in "Ye Mu Gua" might therefore be transformed into their respective aglycones, and thus inhibit the release of inflammatory factors in vivo. This could then account for the clinical value of "Ye Mu Gua" as regards anti-inflammatory effects. This proposed explanation of how "Ye Mu Gua" may have an effect is similar to the concept of prodrugs for chemical drugs which could be extended to some traditional medicines. That is, the major components might be biologically active not directly, but via biochemical transformation in vivo. Hence, we propose a "traditional medicine's prodrug characteristic" concept. PMID:19427657

Gao, Hao; Zhao, Feng; Chen, Guo-Dong; Chen, Shao-Dan; Yu, Yang; Yao, Zhi-Hong; Lau, Brad W C; Wang, Zhao; Li, Jin; Yao, Xin-Sheng

2009-04-01

353

Variegatusides: New Non-Sulphated Triterpene Glycosides from the Sea Cucumber Stichopus variegates Semper  

PubMed Central

Four new triterpene glycosides, variegatusides C–F (1–4), together with three structurally known triterpene glycosides, variegatusides A and B (5, 6), and holothurin B (7), were isolated from the sea cucumber Stichopus variegates Semper (Holothuriidae), collected from the South China Sea. Their structures were elucidated on the basis of extensive spectral analysis (nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESIMS)) and chemical evidence. Variegatusides C–F exhibit the same structural feature consisting of the presence of a 23-hydroxyl group at the holostane-type triterpene aglycone side chain. Variegatuside C (1) has a double bond (24, 25) in this same chain, while variegatuside D (2) exhibits a 8(9)-ene bond in the holostane-type triterpene aglycone, which has not been extracted from other sea cucumber species. Compound 4 is a native compound from the sea cucumber S. variegates Semper, which has been reported to be desacetylstichloroside B1. Except for holothurin B, these glycosides have no sulfate group in their sugar chain and show potent antifungal activities in vitro biotests. PMID:24699115

Wang, Xiao-Hua; Zou, Zheng-Rong; Yi, Yang-Hua; Han, Hua; Li, Ling; Pan, Min-Xiang

2014-01-01

354

Validated high-performance thin-layer chromatography method for steviol glycosides in Stevia rebaudiana.  

PubMed

A high-performance thin-layer chromatographic (HPTLC) method was developed and validated as per ICH (International Conferences on Harmonization) guidelines for simultaneous quantification of three steviol glycosides, i.e. steviolbioside, stevioside and rebaudioside-A in Stevia rebaudiana leaves. For achieving good separation, mobile phase of ethyl acetate-ethanol-water (80:20:12, v/v/v) on pre-coated silica gel 60 F254 HPTLC plates were used. The densitometric quantification of steviol glycosides was carried out at lambda=510 nm in reflection-absorption mode after spraying with acetic anhydride:sulphuric acid:ethanol reagent. The calibration curves were linear in the range of 160-960 ng/spot for steviolbioside, 1-6 microg/spot for stevioside and 0.5-3 microg/spot for rebaudioside-A with good correlation coefficients (0.998-0.999). The method was found to be reproducible for quantitative analysis of steviol glycosides in S. rebaudiana leaves collected from ten different locations and will serve as a quality control indicator to monitor the commercial production of stevioside and its allied molecules during different stages of its processing. PMID:18456448

Jaitak, Vikas; Gupta, A P; Kaul, V K; Ahuja, P S

2008-08-01

355

Steroidal glycosides from Veronica chamaedrys L. Part I. The structures of chamaedrosides C, C1, C2, E, E1 and E2.  

PubMed

Two new spirostane glycosides, chamaedrosides C (1) and C1 (2), two new furostane glycosides, chamaedrosides E (4) and E1 (5), and two new furospirostane glycosides, chamaedrosides C2 (3) and E2 (6), have been isolated from Veronica chamaedrys L. plants. Their structures were determined on the basis of chemical evidence and extensive spectroscopic methods, including 1D- and 2D-NMR experiments, as well as MS analysis. The given compounds have been found for the first time. PMID:22799076

Marchenko, Alexandra; Kintya, Pavel; Wyrzykiewicz, Bozena; Gorincioi, Elena

2012-05-01

356

System-theoretical (Holistic) Approach to the Modelling of Structural–Functional Relationships of Biomolecules and Their Evolution: an Example of Triterpene Glycosides from Sea Cucumbers (Echinodermata, Holothurioidea)  

Microsoft Academic Search

Triterpene glycosides from sea cucumbers (Holothurioidea, Echinodermata) are used as a model for studying the biochemical evolution for correlation between the glycoside membranolytic activity and biological functions. Concepts of evolutionary morphology are applied at the molecular level. The concept of Van-der-Klaauve's– Dullemeijer's system-theoretical (holistic) approach is used for the model of structural–functional relationships of the glycosides. Network diagrams of structural–functional

VLADIMIR I KALININ

2000-01-01

357

Reversible collisionless magnetic reconnection  

SciTech Connect

Reversible magnetic reconnection is demonstrated for the first time by means of gyrokinetic numerical simulations of a collisionless magnetized plasma. Growth of a current-driven instability in a sheared magnetic field is accompanied by magnetic reconnection due to electron inertia effects. Following the instability growth, the collisionless reconnection is accelerated with development of a cross-shaped structure of current density, and then all field lines are reconnected. The fully reconnected state is followed by the secondary reconnection resulting in a weakly turbulent state. A time-reversed simulation starting from the turbulent state manifests that the collisionless reconnection process proceeds inversely leading to the initial state. During the reversed reconnection, the kinetic energy is reconverted into the original magnetic field energy. In order to understand the stability of reversed process, an external perturbation is added to the fully reconnected state, and it is found that the accelerated reconnection is reversible when the deviation of the E × B streamlines due to the perturbation is comparable with or smaller than a current layer width.

Ishizawa, A.; Watanabe, T.-H. [National Institute for Fusion Science, Toki 509-5292 (Japan)] [National Institute for Fusion Science, Toki 509-5292 (Japan)

2013-10-15

358

Reversible adaptive trees.  

PubMed

We describe reversible adaptive trees, a class of stochastic algorithms modified from the formerly described adaptive trees. They evolve in time a finite subset of an ambient Euclidean space of any dimension, starting from a seed point and, accreting points to the evolving set, they grow branches towards a target set which can depend on time. In contrast with plain adaptive trees, which were formerly proven to have strong convergence properties to a static target, the points of reversible adaptive trees are removed from the tree when they have not been used recently enough in a path from the root to an accreted point. This, together with a straightening process performed on the branches, permits the tree to follow some moving targets and still remain adapted to it. We then discuss in what way one can see such reversible trees as a model for a qualitative property of resilience, which leads us to discuss qualitative modeling. PMID:23934230

Kergosien, Yannick L

2013-09-01

359

Antithrombotic reversal agents.  

PubMed

The actively bleeding anticoagulated patient presenting to the emergency department requires rapid evaluation and treatment, which is made increasingly complicated by the ever-evolving antithrombotic treatment options used in medicine. Even with excellent supportive care, the timeliness with which reversal decisions need to be made continues to demand of the emergency practitioner a familiarity with the properties and general characteristics of a variety of antithrombotic agents. Reversal options vary and may include vitamin K, FFP, PCC, rFVIIa, platelets, and desmopressin, among others. PMID:25060258

Wilson, Matthew D; Davis, Jonathan E

2014-08-01

360

Soap Bubbles in Reverse  

Microsoft Academic Search

WHEN sulphuric acid sodium sulphate solution containing surface-active material is dropped into water, bubbles approximately 5 mm. in diameter sinking through water may be observed. Such bubbles are spherical shells of air, with a sphere of acid sodium sulphate within and water outside. They are, in fact, soap bubbles in reverse. Instead of a two-surfaced film of soapy solution in

Leslie Rose

1946-01-01

361

EXPRESS 2006 General reversibility  

E-print Network

) semantics are understood to be reversible. Technically, the theoretical development involved the engineering the configuration of a given process. Appropriate new structural operational semantics (sos) rules allowed is easy enough since policies are normally specified by requiring the local states of the partic- ipants

Danos, Vincent - Laboratoire Preuves, Programmes et Systèmes, Université Paris 7

362

Cells in Reverse  

NSDL National Science Digital Library

For the first time, scientists have reversed the process of cell division: a trick once thought to be as impossible as un-ringing a bell. Molecular biologist Gary Gorbsky of the Oklahoma Medical Research Foundation led the effort. By tinkering with proteins that regulate the process, they turned the clock back from the end of the cell cycle to the middle.

American Association for the Advancement of Science (;)

2006-05-29

363

STUDIES IN REVERSAL AUTORADIOGRAPHY  

Microsoft Academic Search

When an autoradiograph is made with permanent contact between the ; photographical emulsion and the specimen, the active areas can be completely ; hidden by the image, if they are very small. This is overcome by a reversal-; development process leaving the active parts indicated by clear zones against a ; colored transparent background. The sizes of these zones are

Sisefsky

1961-01-01

364

Time reversal communication system  

SciTech Connect

A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

Candy, James V. (Danville, CA); Meyer, Alan W. (Danville, CA)

2008-12-02

365

Effects of Pregnane Glycosides on Food Intake Depend on Stimulation of the Melanocortin Pathway and BDNF in an Animal Model  

PubMed Central

Pregnane glycosides appear to modulate food intake by possibly affecting the hypothalamic feeding circuits; however, the mechanisms of the appetite-regulating effect of pregnane glycosides remain obscure. Here, we show that pregnane glycoside-enriched extracts from swamp milkweed Asclepias incarnata at 25–100 mg/kg daily attenuated food intake (up to 47.1 ± 8.5% less than controls) and body weight gain in rats (10% for males and 9% for females, respectively) by activating melanocortin signaling and inhibiting gastric emptying. The major milkweed pregnane glycoside, ikemagenin, exerted its appetite-regulating effect by decreasing levels of agouti-related protein (0.6-fold) but not NPY satiety peptides. Ikemagenin treatment also increased secretion of brain-derived neurotropic factor (BDNF) downstream of melanocortin receptors in the hypothalamus (1.4-fold) and in the C6 rat glioma cell culture in vitro (up to 6-fold). These results support the multimodal effects of pregnane glycosides on feeding regulation, which depends on the activity of the melanocortin signaling pathway and BDNF. PMID:23308358

Komarnytsky, Slavko; Esposito, Debora; Rathinasabapathy, Thirumurugan; Poulev, Alexander; Raskin, Ilya

2013-01-01

366

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

367

Norsesquiterpene glycosides in bracken ferns (Pteridium esculentum and Pteridium aquilinum subsp. wightianum) from Eastern Australia: reassessed poisoning risk to animals.  

PubMed

Austral bracken Pteridium esculentum contains three unstable norsesquiterpene glycosides: ptaquiloside, ptesculentoside, and caudatoside, in variable proportions. The concentration of each of the glycosides was determined in this study as their respective degradation products, pterosin B, pterosin G and pterosin A, by HPLC-UV analysis. Samples of P. esculentum collected from six sites in eastern Australia contained up to 17 mg of total glycoside/g DW, with both ptaquiloside and ptesculentoside present as major components accompanied by smaller amounts of caudatoside. Ratios of ptaquiloside to ptesculentoside varied from 1:3 to 4:3, but in all Australian samples ptesculentoside was a significant component. This profile differed substantially from that of P. esculentum from New Zealand, which contained only small amounts of both ptesculentoside and caudatoside, with ptaquiloside as the dominant component. A similar profile with ptaquiloside as the dominant glycoside was obtained for Pteridium aquilinum subsp. wightianum (previously P. revolutum ) from northern Queensland and also P. aquilinum from European sources. Ptesculentoside has chemical reactivity similar to that of ptaquiloside and presumably biological activity similar to that of this potent carcinogen. The presence of this additional reactive glycoside in Australian P. esculentum implies greater toxicity for consuming animals than previously estimated from ptaquiloside content alone. PMID:21456622

Fletcher, Mary T; Brock, Ian J; Reichmann, Keith G; McKenzie, Ross A; Blaney, Barry J

2011-05-11

368

Profiling of the resin glycoside content of Mexican jalap roots with purgative activity.  

PubMed

Mexican Jalap roots, a prehispanic medicinal plant complex still considered to be a useful laxative, can be found as an ingredient in some over-the-counter products sold by herbalists in contemporary Mexico. The drug is prepared from the dried roots of several morning glories, all of which have been identified as members of the genus Ipomoea. Analysis of several commercial samples was assessed by generating HPLC and 13C NMR spectroscopic profiles of the glycosidic acids obtained through saponification of the resin glycoside contents. These profiles distinguish the three Mexican jalaps currently in frequent use and can serve as analytical tools for the authentication and quality control of these purgative herbal drugs. Ipomoea purga, the authentic "jalap root", yielded two new hexasaccharides of convolvulinic and jalapinolic acids, purgic acids A (1) and B (2), respectively. Scammonic acid A (3), a tetrasaccharide, was produced from Ipomoea orizabensis, the Mexican scammony or false jalap. Operculinic acid B (4), a pentasaccharide, was identified in Ipomoea stans. Semipreparative HPLC was performed to obtain pure samples of new compounds 1 and 2 in sufficient quantity to elucidate their structure by high-field NMR spectroscopy. Purgic acid A (1) was identified as (11S)-hydroxytetradecanoic acid 11-O-beta-D-quinovopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->3)-O-[beta-D-fucopyranosyl-(1-->4)]-O-alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-quinovopyranoside, while purgic acid B (2) was characterized with (11S)-hydroxyhexadecanoic acid as its aglycon but having the same glycosidation sequence in the oligosaccharide core. PMID:17067162

Pereda-Miranda, Rogelio; Fragoso-Serrano, Mabel; Escalante-Sanchez, Edgar; Hernandez-Carlos, Beatriz; Linares, Edelmira; Bye, Robert

2006-10-01

369

27-Nor-triterpenoid glycosides from the barks of Zygophyllum fabago L  

Microsoft Academic Search

From the bark of Zygophyllum fabago L., a new 27-nor-triterpenoid glycoside, 3-O-?-d-glucopyranosyl-pyrocincholate (1), together with five known compounds, 3-O-6-deoxy-?-d-glucopyranosyl-pyrocincholate (2), quinovic acid (3), 3-O-6-deoxy-?-d-glucopyranosyl-quinovic acid (4), 3-O-?-d-glucopyranosyl- quinovic acid (5) and 3-O-6-deoxy-?-d-glucopyranosyl-cincholic acid (6), were isolated and their structures elucidated on the basis of spectroscopic data. Compounds 1, 2 and 3 showed some anti-tumour activities by MTT assay.

Yu-Lin Feng; He-Ran Li; Li-Zhen Xu; Shi-Lin Yang

2007-01-01

370

27-nor-triterpenoid glycosides from the barks of Zygophyllum fabago L.  

PubMed

From the bark of Zygophyllum fabago L., a new 27-nor-triterpenoid glycoside, 3-O-beta-D-glucopyranosyl-pyrocincholate (1), together with five known compounds, 3-O-6-deoxy-beta-D-glucopyranosyl-pyrocincholate (2), quinovic acid (3), 3-O-6-deoxy-beta-D-glucopyranosyl-quinovic acid (4), 3-O-beta-D-glucopyranosyl- quinovic acid (5) and 3-O-6-deoxy-beta-D-glucopyranosyl-cincholic acid (6), were isolated and their structures elucidated on the basis of spectroscopic data. Compounds 1, 2 and 3 showed some anti-tumour activities by MTT assay. PMID:17885836

Feng, Yu-Lin; Li, He-Ran; Xu, Li-Zhen; Yang, Shi-Lin

2007-01-01

371

Novel Glycoside Hydrolases Identified by Screening a Chinese Holstein Dairy Cow Rumen-Derived Metagenome Library ? †  

PubMed Central

One clone encoding glycoside hydrolases was identified through functional screening of a rumen bacterial artificial chromosome (BAC) library. Of the 68 open reading frames (ORFs) predicted, one ORF encodes a novel endo-?-1,4-xylanase with two catalytic domains of family GH43 and two cellulose-binding modules (CBMs) of family IV. Partial characterization showed that this endo-xylanase has a greater specific activity than a number of other xylanases over a wide temperature range at neutral pH and could be useful in some industrial applications. PMID:20709844

Zhao, Shengguo; Wang, Jiaqi; Bu, Dengpan; Liu, Kailang; Zhu, Yaxin; Dong, Zhiyang; Yu, Zhongtang

2010-01-01

372

A novel sulphur glycoside from the seeds of Descurainia sophia (L.)  

Microsoft Academic Search

A new sulphur glycoside, named descurainoside (1), and the known compound sinapic acid (2) have been isolated from the seeds of Descurainia sophia (L.) Webb ex Prantl. The structure of 1 has been identified as (1R,6S,8R,9S,10S)-9,10-dihydroxy-4-[(4-hydroxy-3,5-dimethoxyphenyl)methylene]-8-(hydroxymethyl)-2,7-dioxa-5-thiabicyclo[4.4.0]decan-3-one by means of physico-chemical properties and spectroscopic methods (1D and 2D NMR, HRMS, ESI-MS).

K. Sun; X. Li; J.-M. Liu; J.-H. Wang; W. Li; Y. Sha

2005-01-01

373

A novel sulphur glycoside from the seeds of Descurainia sophia (L.).  

PubMed

A new sulphur glycoside, named descurainoside (1), and the known compound sinapic acid (2) have been isolated from the seeds of Descurainia sophia (L.) Webb ex Prantl. The structure of 1 has been identified as (1R,6S,8R,9S,10S)-9,10-dihydroxy-4-[(4-hydroxy-3,5-dimethoxyphenyl)methylene]-8-(hydroxymethyl)-2,7-dioxa-5-thiabicyclo[4.4.0]decan-3-one by means of physico-chemical properties and spectroscopic methods (1D and 2D NMR, HRMS, ESI-MS). PMID:16308204

Sun, K; Li, X; Liu, J-M; Wang, J-H; Li, W; Sha, Y

2005-12-01

374

Fast repair of thymine-hydroxyl radical adduct by phenylpropanoid glycosides  

NASA Astrophysics Data System (ADS)

The repair effect on thymine-hydroxyl adduct by phenylpropanoid glycosides (PPG): verbascoside, and pedicularioside A, isolated from Pedicularis, were studied using pulse radiolysis technique. From the analysis of transient absorption spectra, the rapid electron transfer from PPG to T-OH - was observed. Phenoxyl radical of PPG were generated via one-electron-transfer reaction. This result showed that two PPG exhibited repair activities on oxidizing T-OH -. The reaction rate constants of electron transfer from PPGs were 1.27 × 10 9 and 1.29 × 10 9 dm 3·mol -1s -1 respectively.

Wenyan, Li; Zhihua, Zou; Rongliang, Zheng; Changzeng, Wang; Zhongjian, Jia; Side, Yao; Nianyun, Lin

375

Fast repair of thymine-hydroxyl radical adduct by phenylpropanoid glycosides  

NASA Astrophysics Data System (ADS)

The repair effect on thymine-hydroxyl adduct by phenylpropanoid glycosides (PPG): verbascoside, and pedicularioside A, isolated from Pedicularis, were studied using pulse radiolysis technique. From the analysis of transient absorption spectra, the rapid electron transfer from PPG to T-OH- was observed. Phenoxyl radical of PPG were generated via one-electron-transfer reaction. This result showed that two PPG exhibited repair activities on oxidizing T-OH-. The reaction rate constants of electron transfer from PPGs were 1.27 × 109 and 1.29 × 109 dm3.mol-1.s-1, respectively.

Li, Wenyan; Zou, Zhihua; Zheng, Rongliang; Wang, Changzeng; Jia, Zhongjian; Yao, Side; Lin, Nianyun

1997-04-01

376

Two new unusual monoterpene acid glycosides from Acacia cyclops with potential cytotoxic activity.  

PubMed

A phytochemical investigation of the Tunisian plant Acacia cyclops pods led to the isolation of two new monoterpenoid glycosides, which have been designated Cyclopside 1 and Cyclopside 2. Their structures were elucidated on the basis of extensive spectroscopic procedures including IR, MS and 2D-NMR. The cytotoxic effect of the isolates was also evaluated in vitro against the human breast cancer (MCF-7) and ovarian cancer (OVAR) cell lines. Results showed that the highest cytotoxic activity (90.88%) was against MCF-7 cell line and was exhibited by the Cyclopside 1 at the concentration of 50 ?g/mL. PMID:25082124

Jelassi, Amira; Zardi-Bergaoui, Afifa; Ben Nejma, Aymen; Belaiba, Meriam; Bouajila, Jalloul; Ben Jannet, Hichem

2014-08-15

377

Structures of new phenolic glycosides from the seeds of Cucurbita moschata.  

PubMed

A new phenolic glycoside and three known compounds were isolated from the seeds of Cucurbita moschata. The structures of the new compound was elucidated as phenylcarbinyl 5-O-(4-hydroxy)benzoyl-beta-D-apiofuranosyl (1-->2)-beta-D-glucopyranoside on the basis of spectroscopic analysis and chemical evidence. Three known compounds were identified as 1-O-benzyl[5-O-benzoyl-beta-D-apiofuranosyl(1-->2)]-beta-D-glucopyranoside 2, cucurbitosides C 3 and A 4, by comparison of the spectral data with reported data. Compound 2 was isolated from this plant for the first time. PMID:19475995

Li, Fa-Sheng; Xu, Jing; Dou, De-Qiang; Chi, Xiao-Feng; Kang, Ting-Guo; Kuang, Hai Xue

2009-04-01

378

Three new glycosides from the leaves of Hydrangea macrophylla subsp. serrata (THUNB.) MAKINO.  

PubMed

Three new glycosides, 7-deoxyloganic acid beta-D-glucopyranosyl ester (1), (3R)-hydrangenol 8,4'-di-O-beta-D-glucopyranoside (2), and (6R,7E,9R)-megastigma-4,7-dien-3-one 9,13-di-O-beta-D-glucopyranoside (3), have been isolated from the leaves of Hydrangea macrophylla subsp. serrata (THUNB.) MAKINO (Saxifragaceae). The structures of 1-3 were elucidated on the basis of spectral data and chemical evidence. PMID:18379120

Kikuchi, Masao; Kakuda, Rie; Kikuchi, Masafumi; Yaoita, Yasunori

2008-04-01

379

Two new glycosides from the whole plants of Glechoma hederacea L.  

PubMed

Two new glycosides, 7S,7'S,8R,8'R-icariol A(2)-9-O-beta-D-glucopyranoside (1) and 4-allyl-2-hydroxyphenyl 1-O-beta-D-apiosyl-(1-->6)-beta-D-glucopyranoside (2), were isolated from the dried whole plants of Glechoma hederacea L. (Labiatae) together with four known compounds, cistanoside E (3), dihydrodehydrodiconiferyl alcohol 4-O-beta-D-glucopyranoside (4), apigenin 7-O-beta-D-glucuronopyranoside (5) and luteolin 7-O-beta-D-glucopyranoside (6). The structures of the new compounds were elucidated on the basis of chemical and spectral analysis. PMID:17268115

Yamauchi, Hirotsugu; Kakuda, Rie; Yaoita, Yasunori; Machida, Koichi; Kikuchi, Masao

2007-02-01

380

Steroidal glycosides from the underground parts of Dracaena thalioides and their cytotoxic activity.  

PubMed

Six spirostanol glycosides (1-6) and 12 known compounds (7-18) were isolated from the underground parts of Dracaena thalioides (Agavaceae). Their structures were determined by spectroscopic analysis, including 2D NMR spectroscopic data, and chemical transformations. The isolated compounds were evaluated for cytotoxic activity against HL-60 human leukemia cells. Compounds 1, 3-6, and 8-18 showed cytotoxicity against HL-60 cells, of which 10, a bisdesmosidic spirostanol derivative, showed potent cytotoxicity against HL-60 cells with an IC50 value of 0.38?M and induced apoptosis in HL-60 cells. PMID:25152452

Tang, Liying; Wang, Zhuju; Wu, Hongwei; Yokosuka, Akihito; Mimaki, Yoshihiro

2014-11-01

381

Verticillosides A-M: Polyoxygenated pregnane glycosides from Asclepias verticillata L.  

PubMed

As part of our ongoing effort to explore the chemical diversity of plants of the United States Midwest region, the isolation and identification of 13 pregnane glycosides named verticillosides A-M from Asclepias verticillata L. are reported. The structures of these compounds were elucidated by various spectroscopic techniques, including 1D and 2D NMR, IR, UV, and HRMS. The cytotoxicity of the isolates was evaluated against paired breast cell lines Hs578T (cancer) and Hs578Bst (normal), however, no significant growth inhibition was observed. PMID:22445072

Araya, Juan J; Binns, Franklin; Kindscher, Kelly; Timmermann, Barbara N

2012-06-01

382

A new phenyl glycoside from the aerial parts of Equisetum hyemale.  

PubMed

A new phenyl glycoside, 2-(sophorosyl)-1-(4-hydroxyphenyl)ethanone (9), was isolated from the ethanolic extract of the aerial parts of Equisetum hyemale L., together with eight known compounds (1-8). The structures of these compounds were elucidated using a combination of spectroscopic analyses and chemical method. Of these nine compounds, 4 and 7 showed hepatoprotective effects towards tacrine-induced cytotoxicity in Hep 3B cells with EC50 values of 42.7 ± 1.5 and 132.6 ± 2.8 ?M, respectively. PMID:25117054

Jin, Mei; Zhang, Changhao; Zheng, Tie; Yao, Dalei; Shen, Le; Luo, Jie; Jiang, Zhe; Ma, Juan; Jin, Xue-Jun; Cui, Jiongmo; Lee, Jung Joon; Li, Gao

2014-11-01

383

Structures of two new steroidal glycosides, soladulcosides A and B from Solanum dulcamara.  

PubMed

The structures of two new steroidal glycosides named soladulcosides A and B, isolated from the aerial parts of Solanum dulcamara including new sapogenols, were elucidated as (22R, 25R)-3 beta, 15 alpha, 23 alpha-trihydroxy-5 alpha-spirostan-26-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-beta-D-glucopyranoside and (22R, 25R)-3 beta,23 alpha-dihydroxy-5 alpha-spirostan-26-one 3-O-alpha-L-rhamnopyranosyl-(1----2)-[alpha-L-rhamnopyranosyl-(1----4)]- beta-D-glucopyranoside, respectively. PMID:1934188

Yamashita, T; Matsumoto, T; Yahara, S; Yoshida, N; Nohara, T

1991-06-01

384

Synthesis and evaluation of iminocoumaryl and coumaryl derivatized glycosides as galectin antagonists.  

PubMed

A collection of iminocoumarylmethyl glycoside derivatives have been prepared by copper-catalyzed multi-component reaction of carbohydrate propargyl derivatives, sulfonyl azides, and salicylaldehyde or o-hydroxy acetophenone. The method is simple, versatile to all three components, and exceptionally high yielding. The carbohydrate N-sulfonyl iminocoumarine hybrid molecules were evaluated for binding galectin-1, -2, -3, -4N, -4C, -7, -8N, -9N, and 9C using a competitive fluorescence polarization assay. Selective compounds were identified against galectin-3, 7, 8N, and 9N with up to 40-fold affinity enhancements relative to methyl ?-d-galactopyranoside due to the coumarylmethyl moieties. PMID:24973029

Rajput, Vishal Kumar; Leffler, Hakon; Nilsson, Ulf J; Mukhopadhyay, Balaram

2014-08-01

385

Shamiminol: a new aromatic glycoside from the stem bark of Bombax ceiba.  

PubMed

A new aromatic glycoside, shamiminol was isolated from the stem bark of Bombax ceiba along with the known constituents stigmasta-3,5-diene, lupenone, (+/-)-lyoniresinol 2a-O-beta-D-glucopyranoside and opuntiol, obtained for the first time from this plant. The structure of shamiminol was elucidated on the basis of extensive 1D- and 2D-NMR spectroscopic and mass spectrometric studies as 3,4,5-trimethoxyphenol 1-O-beta-D-xylopyranosyl-(1 --> 2)-beta-D-glucopyranoside (1). PMID:22312733

Faizi, Shaheen; Zikr-Ur-Rehman, Sadia; Versiani, Muhammad Ali

2011-12-01

386

Stability of black cohosh triterpene glycosides and polyphenols: potential clinical relevance.  

PubMed

Concurrent to a clinical trial of black cohosh for menopausal hot flashes, the long-term stability of the black cohosh, over the duration of the clinical trial, was examined. Analytical results showed that the major constituents, both triterpene glycosides and polyphenols, were stable over the 3-year period of testing. These results indicate that a black cohosh product stored for several years in a controlled environment does not undergo significant changes in its major constituents. These results have implications not only for clinical research in natural products, but for basic science, as well as the dietary supplements industry. PMID:23415548

Jiang, Bei; Kronenberg, Fredi; Balick, Michael J; Kennelly, Edward J

2013-04-15

387

Two new ionone glycosides from the roots of Rehmannia glutinosa Libosch.  

PubMed

Two new ionone glycosides, named frehmaglutoside G (1) and frehmaglutoside H (2), together with six known compounds, rehmapicroside (3), sec-hydroxyaeginetic acid (4), dihydroxy-?-ionone (5), trihydroxy-?-ionone (6), rehmaionoside A (7) and rehmaionoside C (8), were isolated from the 95% EtOH extract of the dried roots of Rehmannia glutinosa Libosch. Their structures were determined on the basis of extensive spectroscopic analyses, including HR-ESI-MS, UV, IR, 1D and 2D NMR ((1)H-(1)H COSY, HSQC, HMBC and NOESY) methods. The absolute configurations were confirmed via the circular dichroism spectra. PMID:25232801

Feng, Wei-Sheng; Li, Meng; Zheng, Xiao-Ke; Zhang, Na; Song, Kai; Wang, Jian-Chao; Kuang, Hai-Xue

2015-01-01

388

Unusual cytotoxic sulfated cadinene-type sesquiterpene glycosides from cottonseed ( Gossypium hirsutum)  

Microsoft Academic Search

Two new sulfated cadinene-type sesquiterpene glycosides, 13-hydroxy-7-O-(6?-O-sulfate-?-d-glucopyranosyl)-desoxyhemigossypol (1) and 13,15-dihydroxy-7-O-(6?-O-sulfate-?-d-glucopyranosyl)-desoxyhemigossypol (2), have been isolated from whole cottonseed (Gossypium hirsutum). Their structures, which possess an unusual 6-O-sulfate-glucopyranosyl moiety, were determined through the interpretation of 2D NMR spectral data and H\\/D exchange ESI-MS experiments. Compounds 1 and 2 were screened for their toxicity on Jurkat cells. Both compounds inhibited cellular proliferation with

Anna Lisa Piccinelli; Cinzia Lotti; Lorella Severino; Diomira Luongo; Luca Rastrelli

2008-01-01

389

Partial Reversible Gates(PRG) for Reversible BCD Arithmetic  

E-print Network

IEEE 754r is the ongoing revision to the IEEE 754 floating point standard and a major enhancement to the standard is the addition of decimal format. Furthermore, in the recent years reversible logic has emerged as a promising computing paradigm having its applications in low power CMOS, quantum computing, nanotechnology, and optical computing. The major goal in reversible logic is to minimize the number of reversible gates and garbage outputs. Thus, this paper proposes the novel concept of partial reversible gates that will satisfy the reversibility criteria for specific cases in BCD arithmetic. The partial reversible gate is proposed to minimize the number of reversible gates and garbage outputs, while designing the reversible BCD arithmetic circuits.

Thapliyal, Himanshu; Bajpai, Rajnish; Sharma, Kamal K

2007-01-01

390

Regioselective synthesis of p-nitrophenyl glycosides of ?- d-galactopyranosyl-disaccharides by transglycosylation with ?- d-galactosidases  

Microsoft Academic Search

The ?-d-galactosidase from porcine liver induced regiospecific transglycosylation of ?-d-galactose from ?-d-Gal-OC6H4NO2-o to OH-6 of, respectively, p-nitrophenyl glycoside acceptors of Gal, GlcNAc and GalNAc to afford ?-Gal-(1?6)-?-Gal-OC6H4NO2-p, ?-Gal-(1?6)-?-Gal-OC6H4NO2-p, ?-Gal-(1?6)-?-GalNAc-OC6H4NO2-p, ?-Gal-(1?6)-?-GalNAc-OC6H4NO2-p, ?-Gal-(1?6)-?-GlcNAc-OC6H4NO2-p, and ?-Gal-(1?6)-?-GlcNAc-OC6H4NO2-p. The enzyme showed much higher transglycosylation activity for the ?-glycoside acceptors than the corresponding ?-glycoside acceptors. The regioselectivity of the ?-d-galactosidase from Bacilluscirculans ATCC 31382 greatly depended

Xiaoxiong Zeng; Rika Yoshino; Takeomi Murata; Katsumi Ajisaka; Taichi Usui

2000-01-01

391

Polymerized liposomes containing C-glycosides of sialic acid: Potent inhibitors of influenza virus in vitro infectivity  

SciTech Connect

The surface lectin of the influenza virus, hemagglutinin, binds to terminal [alpha]-glycosides of N-acetylneuraminic acid (NeuAc) on cell-surface glycoproteins and glycolipids. Viral binding to cells expression terminal NeuAc residues can be inhibited by [alpha]-O-glycosides of NeuAc (O-sialosides). Recently, dramatic enhancements in the inhibition of viral adhesion to erythrocytes have been achieved using synthetic polyvalent sialosides. In this communication, the authors report that polymerized liposomes containing [alpha]-C-glycosides of sialic acid are potent inhibitors of influenza virus in vitro infectivity. Their results also indicate that the capacity to inhibit hemagglutination does not necessarily reflect the capacity to inhibit in vitro infectivity. 14 refs., 1 tab.

Spevak, W.; Bednarski, M.D.; Nagy, J.O.; Charych, D.H (Lawrence Berkeley Lab., CA (United States)); Schaefer, M.E.; Gilbert, J.H. (Glycomed, Inc., Alameda, CA (United States))

1993-02-10

392

Quantitative analysis of cycloartane glycosides in black cohosh rhizomes and dietary supplements by RRLC-ELSD and RRLC-qTOF-MS.  

PubMed

In this study, a fast and reproducible RRLC-ELSD method for the quantitative analysis of 17 cycloartane glycosides and the aglycone cimigenol in black cohosh rhizomes and dietary supplements has been developed. Separation of the 18 triterpenes was achieved within 16 min using reversed phase material and a gradient elution system consisting of water, acetonitrile and methanol. The method was validated for accuracy (recovery rates from 96.79% to 102.86%), precision (intra-day variation ?5.98%, inter-day variation ?3.74%), repeatability (R.S.D.???6.94%) and sensitivity, with detection limits below 4.0 ?g/mL and quantification limits lower than 13.2 ?g/mL. Calibration curves were established in the range from 5-1,000 ?g/mL, with correlation coefficients higher than 0.998 for all constituents investigated. Peak purity and peak assignment were confirmed by means of RRLC-qTOF-MS and in comparison with reference compounds. Three different MS sources (ESI, APCI and APPI) were compared for their ionisation potential regarding cycloartane derivatives. One of the isolated black cohosh constituents, 24-O-acetylhydroshengmanol-3-O-?-L-arabinopyranoside, could be identified as new natural compound. PMID:20694806

Cicek, Serhat S; Aberham, Anita; Ganzera, Markus; Stuppner, Hermann

2011-06-01

393

Analysis of eleven iridoid glycosides by micellar electrokinetic capillary chromatography (MECC) and screening of plant samples by partial filling (MECC)–electrospray ionisation mass spectrometry  

Microsoft Academic Search

Of ammonium, lithium and sodium salts of dodecyl sulfate studied as surfactants in the separation of iridoid glycosides by micellar electrokinetic capillary chromatography (MECC), the last one gave the best results. Eleven neutral iridoid glycosides were separated by MECC with sodium dodecyl sulfate as surfactant, and the water–micelle partition coefficients of the compounds were calculated. The separation system was coupled

Johanna Suomi; Susanne K Wiedmer; Matti Jussila; Marja-Liisa Riekkola

2002-01-01

394

Systemic, Genotype-Specific Induction of Two Herbivore-Deterrent Iridoid Glycosides in Plantago lanceolata L. in Response to Fungal Infection by Diaporthe adunca (Rob.) Niessel  

Microsoft Academic Search

Iridoid glycosides are a group of terpenoid secondary plant compounds known to deter generalist insect herbivores. In ribwort plantain (Plantago lanceolata), the iridoid glycosides aucubin and catalpol can be induced following damage by insect herbivores. In this study, we investigated whether the same compounds can be induced following infection by the fungal pathogen Diaporthe adunca, the causal agent of a

Hamida B. Marak; Arjen Biere; Jos M. M. Van Damme

2002-01-01

395

Identification of flavonoid glycosides in Rosa chinensis flowers by liquid chromatography-tandem mass spectrometry in combination with ¹³C nuclear magnetic resonance.  

PubMed

Flowers of Rosa chinensis are widely used in traditional Chinese medicine as well as in food industry. Flavonoid glycosides are believed to be the major components in R. chinensis that are responsible for its antioxidant activities. In this work, a liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for analysis of flavonoid glycosides presented in ethyl acetate extract of dried R. chinensis flowers. Twelve flavonoid glycosides were separated and detected. By comparing the retention times, UV spectra, and tandem MS fragments with those of respective authentic compounds, eight flavonoid glycosides were unequivocally identified. Although the other four were also identified as flavonoid glycosides, the glycosylation positions could not be determined due to lack of authentic compounds. Fortunately, the glycosylation effects were clearly observed in the (13)C NMR spectrum of the extract. The detailed structural information was, therefore, obtained to identify the four flavonoid glycosides as quercetin-3-O-D-glucoside, quercetin-3-O-D-xyloside, kaempferol-3-O-D-xyloside and quercetin-3-O-D-(6?-coumaroyl)-galactoside. These flavonoid glycosides were detected and identified for the first time in this botanic material. This work reports on the first use of (13)C NMR of a mixture to enhance a rapid HPLC-MS/MS analysis. The proposed analytical protocol was validated with a mixture of authentic flavonoid glycosides. PMID:22749452

Qing, Lin-Sen; Xue, Ying; Zhang, Jian-Guang; Zhang, Zhi-Feng; Liang, Jian; Jiang, Yan; Liu, Yi-Ming; Liao, Xun

2012-08-01

396

Phenolic glycosides and condensed tannins in Salix sericea, S. eriocephala and their F1 hybrids: not all hybrids are created equal  

Microsoft Academic Search

The performance of hybrids depends upon the inheritance and expression of resistance traits. Secondary chemicals are one such resistance trait. In this study, we measured the concentrations of phenolic glycosides and condensed tannins in parental and F1 hybrid willows to examine the sources of chemical variation among hybrids. S. sericea produces phenolic glycosides, salicortin and 2?-cinnamoylsalicortin, and low concentrations of

Colin M. Orians; Megan E Griffiths; Bernadette M. Roche; Robert S. Fritz

2000-01-01

397

Gridded electron reversal ionizer  

NASA Technical Reports Server (NTRS)

A gridded electron reversal ionizer forms a three dimensional cloud of zero or near-zero energy electrons in a cavity within a filament structure surrounding a central electrode having holes through which the sample gas, at reduced pressure, enters an elongated reversal volume. The resultant negative ion stream is applied to a mass analyzer. The reduced electron and ion space-charge limitations of this configuration enhances detection sensitivity for material to be detected by electron attachment, such as narcotic and explosive vapors. Positive ions may be generated by generating electrons having a higher energy, sufficient to ionize the target gas and pulsing the grid negative to stop the electron flow and pulsing the extraction aperture positive to draw out the positive ions.

Chutjian, Ara (Inventor)

1993-01-01

398

Engineering in Reverse!  

NSDL National Science Digital Library

Students learn about the process of reverse engineering and how this technique is used to improve upon technology. Students analyze push-toys and draw diagrams of the predicted mechanisms inside the toys. Then, they disassemble the toys and draw the actual inner mechanisms. By understanding how the push-toys function, students make suggestions for improvement, such as cost effectiveness, improved functionality, ecological friendliness and any additional functionality they determine is an improvement.

Integrated Teaching And Learning Program

399

Diterpenoids and phenylethanoid glycosides from the roots of Clerodendrum bungei and their inhibitory effects against angiotensin converting enzyme and ?-glucosidase.  

PubMed

Abietane derivatives, bungnates A, B, 15-dehydrocyrtophyllone A and 15-dehydro-17-hydroxycyrtophyllone A, and two phenylethanoid glycosides, bunginoside A and 3?,4?-di-O-acetylmartynoside, together with nine known abietane derivatives and fourteen known phenylethanoid glycosides, were isolated from dried roots of Clerodendrum bungei. Their structures were determined on the basis of detailed spectroscopic analyses and acidic hydrolysis. The absolute configuration of bunginoside A was established from analysis of CD data. Selected compounds were evaluated for inhibitory effects against angiotensin converting enzyme (ACE) and ?-glucosidase. 15-Dehydrocyrtophyllone A showed an ACE inhibitory effect, and verbascoside, leucosceptoside A and isoacteoside exhibited strong inhibitory capacity against ?-glucosidase. PMID:24726372

Liu, Qing; Hu, Hai-Jun; Li, Peng-Fei; Yang, Ying-Bo; Wu, Li-Hong; Chou, Gui-Xin; Wang, Zheng-Tao

2014-07-01

400

Analysis of eleven iridoid glycosides by micellar electrokinetic capillary chromatography (MECC) and screening of plant samples by partial filling (MECC)-electrospray ionisation mass spectrometry.  

PubMed

Of ammonium, lithium and sodium salts of dodecyl sulfate studied as surfactants in the separation of iridoid glycosides by micellar electrokinetic capillary chromatography (MECC), the last one gave the best results. Eleven neutral iridoid glycosides were separated by MECC with sodium dodecyl sulfate as surfactant, and the water-micelle partition coefficients of the compounds were calculated. The separation system was coupled via a coaxial sheath flow electrospray interface to a mass spectrometer, and the partial filling technique was used in the on-line analysis. Seven plant species belonging to five genera (Plantago, Veronica, Melampyrum, Succisa and Valeriana) were screened for the iridoid glycosides by the new method that was developed. The findings confirmed those of an earlier study on five of the iridoid glycosides. Some new iridoid glycosides were found in Plantago lanceolata, Veronica spicata and V. chamaedrys. PMID:12350101

Suomi, Johanna; Wiedmer, Susanne K; Jussila, Matti; Riekkola, Marja-Liisa

2002-09-13

401

Species restriction of the mitogenicity induced by lanatoside C. Lymphocyte activation by digitalis glycosides is confined to cells from digitalis resistant species.  

PubMed Central

Activation of Na+, K+-ATPase has previously been suggested to be the triggering signal in mitogen-induced cell activation. Using a digitalis glycoside known to be a potent polyclonal B-cell activator, this hypothesis could be tested since digitalis activates ATPase at different concentrations in various species, depending on the degree of sensitivity to the toxic effects of glycosides. Lanatoside C was found to stimulate lymphocytes from glycoside resistant species such as rat, mouse and hamster. The possible involvement of Na+, K+-ATPase was made less likely by the similarity in dose--response profile in these cells although they have been reported to display varying degrees of glycoside resistance. Furthermore, using lymphocytes from digitalis-sensitive species such as man, guinea-pig or rabbit, no mitogenicity could be recorded, strongly suggesting a lack of correlation between glycoside-induced effects on Na+, K+-ATPase and cell activation. PMID:157324

Hammarstrom, L; Smith, C I

1979-01-01

402

Identification of flavonol and xanthone glycosides from mango (Mangifera indica L. Cv. "Tommy Atkins") peels by high-performance liquid chromatography-electrospray ionization mass spectrometry.  

PubMed

Flavonol O- and xanthone C-glycosides were extracted from mango (Mangifera indica L. cv. "Tommy Atkins") peels and characterized by high-performance liquid chromatography-electrospray ionization mass spectrometry. Among the fourteen compounds analyzed, seven quercetin O-glycosides, one kaempferol O-glycoside, and four xanthone C-glycosides were found. On the basis of their fragmentation pattern, the latter were identified as mangiferin and isomangiferin and their respective galloyl derivatives. A flavonol hexoside with m/z 477 was tentatively identified as a rhamnetin glycoside, which to the best of our knowledge, has not yet been reported in mango peels. The results obtained in the present study confirm that peels originating from mango fruit processing are a promising source of phenolic compounds that might be recovered and used as natural antioxidants or functional food ingredients. PMID:12903961

Schieber, Andreas; Berardini, Nicolai; Carle, Reinhold

2003-08-13

403

Comparative Analysis of Glycoside Hydrolases Activities from Phylogenetically Diverse Marine Bacteria of the Genus Arenibacter  

PubMed Central

A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active ?-N-acetylglucosaminidases and ?-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH) families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases. PMID:23752354

Bakunina, Irina; Nedashkovskaya, Olga; Balabanova, Larissa; Zvyagintseva, Tatyana; Rasskasov, Valery; Mikhailov, Valery

2013-01-01

404

New cardenolide glycosides from the seeds of Digitalis purpurea and their cytotoxic activity.  

PubMed

A chemical investigation of Digitalis purpurea seeds led to the isolation of three new cardenolide glycosides (1, 8 and 11), together with 12 known cardenolide glycosides (2-7, 9, 10 and 12-15). The structures of 1, 8 and 11 were determined by 1D and 2D NMR spectroscopic analyses and the results of an acid or enzymatic hydrolysis. The cytotoxic activity of the isolated compounds (1-15) against HL-60 leukemia cells was examined. Compounds 2, 9, 11 and 12 showed potent cytotoxicity against HL-60 cells with respective 50% inhibition concentration (IC50) values of 0.060, 0.069, 0.038, and 0.034 µM. Compounds 2, 9 and 11 also exhibited potent cytotoxic activity against HepG2 human liver cancer cells with respective IC50 values of 0.38, 0.79, and 0.71 µM. An investigation of the structure-activity relationship showed that the cytotoxic activity was reduced by the introduction of a hydroxy group at C-16 of the digitoxigenin aglycone, methylation of the C-3' hydroxy group at the fucopyranosyl moiety, and acetylation of the C-3' hydroxy group at the digitoxopyranoyl moiety. PMID:23748755

Kuroda, Minpei; Kubo, Satoshi; Matsuo, Yukiko; Atou, Tomomi; Satoh, Junichi; Fujino, Tomofumi; Hayakawa, Makio; Mimaki, Yoshihiro

2013-01-01

405

Phenylethanoid glycosides from Digitalis purpurea and Penstemon linarioides with PKCalpha-inhibitory activity.  

PubMed

In a continuation of our search for potential tumor inhibitors from plants, it was found that the CH2Cl2-MeOH (1:1) extracts from Digitalis purpurea and Penstemon linarioides both showed PKCalpha-inhibitory bioactivity. Bioassay-directed fractionation of the extract from D. purpurea yielded the new, weakly active phenylethanoid glycoside 2-(3-hydroxy-4-methoxy-phenyl)-ethyl-O-(alpha-L-rhamnosyl)-(1-->3) -O- (alpha-L-rhamnosyl)-(1-->6)-4-O-E-feruloyl-beta-D-glucopy ran oside (1) together with the four known compounds calceolarioside A (2), calceolarioside B (3), forsythiaside (4), and plantainoside D (5). The extract from P. linarioides yielded the three known glycosides leucosceptoside A (6), acteoside (7), and poliumoside (8), together with the iridoid plantarenaloside (9). All of the isolated compounds, except compound 9, showed inhibitory activity against PKCalpha with IC50 values (in microM) of 125 (1), 0.6 (2), 4.6 (3), 1.9 (4), 14.8 (5), 19.0 (6), 9.3 (7), and 24.4 (8). PMID:9834166

Zhou, B N; Bahler, B D; Hofmann, G A; Mattern, M R; Johnson, R K; Kingston, D G

1998-11-01

406

Biogenesis of C-Glycosyl Flavones and Profiling of Flavonoid Glycosides in Lotus (Nelumbo nucifera)  

PubMed Central

Flavonoids in nine tissues of Nelumbo nucifera Gaertner were identified and quantified by high-performance liquid chromatography with diode array detector (HPLC-DAD) and HPLC-electrospray ionization-mass spectrometry (HPLC-ESI-MSn). Thirty-eight flavonoids were identified; eleven C-glycosides and five O-glycosides were discovered for the first time in N. nucifera. Most importantly, the C-glycosyl apigenin or luteolin detected in lotus plumules proved valuable for deep elucidation of flavonoid composition in lotus tissues and for further utilization as functional tea and medicine materials. Lotus leaves possessed the significantly highest amount of flavonoids (2.06E3±0.08 mg 100 g?1 FW) and separating and purifying the bioactive compound, quercetin 3-O-glucuronide, from leaves showed great potential. In contrast, flavonoids in flower stalks, seed coats and kernels were extremely low. Simultaneously, the optimal picking time was confirmed by comparing the compound contents in five developmental phases. Finally, we proposed the putative flavonoid biosynthesis pathway in N. nucifera. PMID:25279809

Li, Shan-Shan; Wu, Jie; Chen, Li-Guang; Du, Hui; Xu, Yan-Jun; Wang, Li-Jing; Zhang, Hui-Jin; Zheng, Xu-Chen; Wang, Liang-Sheng

2014-01-01

407

Biogenesis of C-Glycosyl Flavones and Profiling of Flavonoid Glycosides in Lotus (Nelumbo nucifera).  

PubMed

Flavonoids in nine tissues of Nelumbo nucifera Gaertner were identified and quantified by high-performance liquid chromatography with diode array detector (HPLC-DAD) and HPLC-electrospray ionization-mass spectrometry (HPLC-ESI-MSn). Thirty-eight flavonoids were identified; eleven C-glycosides and five O-glycosides were discovered for the first time in N. nucifera. Most importantly, the C-glycosyl apigenin or luteolin detected in lotus plumules proved valuable for deep elucidation of flavonoid composition in lotus tissues and for further utilization as functional tea and medicine materials. Lotus leaves possessed the significantly highest amount of flavonoids (2.06E3±0.08 mg 100 g-1 FW) and separating and purifying the bioactive compound, quercetin 3-O-glucuronide, from leaves showed great potential. In contrast, flavonoids in flower stalks, seed coats and kernels were extremely low. Simultaneously, the optimal picking time was confirmed by comparing the compound contents in five developmental phases. Finally, we proposed the putative flavonoid biosynthesis pathway in N. nucifera. PMID:25279809

Li, Shan-Shan; Wu, Jie; Chen, Li-Guang; Du, Hui; Xu, Yan-Jun; Wang, Li-Jing; Zhang, Hui-Jin; Zheng, Xu-Chen; Wang, Liang-Sheng

2014-01-01

408

Effects of Cardiac Glycosides on Electrical Activity in the Isolated Retina of the Frog  

PubMed Central

Ouabain added to physiological salt solutions bathing the isolated frog retina irreversibly abolishes the electrical response to light (the electroretinogram or ERG). The time course of abolition depends on the concentration of ouabain in the medium and the surface of the retina to which it is applied. When the glycoside is placed on the receptor surface, in 7 min the ERG is completely eliminated by 10-4 M ouabain and more than 90% inhibited by 3 x 10-5 M ouabain. The effect is slower at lower concentrations and when the solution is applied to the vitreous surface of the retina. The evidence suggests that abolition of the ERG by ouabain is due principally to inhibition of the active transport of sodium: (a) Structurally modified glycosides which are considerably less potent inhibitors of alkali cation-activated ATPase activity in preparations of frog retinal outer segments are also poorer inhibitors of electrical activity in isolated retinas. (b) Replacing much of the sodium in the medium bathing the retina by choline, Tris, or sucrose significantly protects the retina from ouabain. It is suggested that in a standard sodium environment essentially constant activity of the sodium pump is required to prevent rapid and irreversible change. The cellular sites most critically dependent on the sodium pump have not been identified. PMID:6034759

Frank, Robert N.; Goldsmith, Timothy H.

1967-01-01

409

Zebrafish Bioassay-Guided Microfractionation Identifies Anticonvulsant Steroid Glycosides from the Philippine Medicinal Plant Solanum torvum.  

PubMed

Medicinal plants used for the treatment of epilepsy are potentially a valuable source of novel antiepileptic small molecules. To identify anticonvulsant secondary metabolites, we performed an in vivo, zebrafish-based screen of medicinal plants used in Southeast Asia for the treatment of seizures. Solanum torvum Sw. (Solanaceae) was identified as having significant anticonvulsant activity in zebrafish larvae with seizures induced by the GABAA antagonist pentylenetetrazol (PTZ). This finding correlates well with the ethnomedical use of this plant in the Philippines, where a water decoction of S. torvum leaves is used to treat epileptic seizures. HPLC microfractionation of the bioactive crude extract, in combination with the in vivo zebrafish seizure assay, enabled the rapid localization of several bioactive compounds that were partially identified online by UHPLC-TOF-MS as steroid glycosides. Targeted isolation of the active constituents from the methanolic extract enabled the complete de novo structure identification of the six main bioactive compounds that were also present in the traditional preparation. To partially mimic the in vivo metabolism of these triterpene glycosides, their common aglycone was generated by acid hydrolysis. The isolated molecules exhibited significant anticonvulsant activity in zebrafish seizure assays. These results underscore the potential of zebrafish bioassay-guided microfractionation to rapidly identify novel bioactive small molecules of natural origin. PMID:25127088

Challal, Soura; Buenafe, Olivia E M; Queiroz, Emerson F; Maljevic, Snezana; Marcourt, Laurence; Bock, Merle; Kloeti, Werner; Dayrit, Fabian M; Harvey, Alan L; Lerche, Holger; Esguerra, Camila V; de Witte, Peter A M; Wolfender, Jean-Luc; Crawford, Alexander D

2014-10-15

410

Pretreatment of baicalin and wogonoside with glycoside hydrolase: A promising approach to enhance anticancer potential  

PubMed Central

Previous phytochemical studies showed that the major flavonoids in Scutellaria baicalensis are baicalin, baicalein, wogonoside and wogonin. The two glycosides (baicalin and wogonoside) can be transformed into their aglycons (baicalein and wogonin), which possess positive anticancer potential. In this study, we used glycosidase to catalyze flavonoids in S. baicalensis to enhance the herb’s anticancer activities. Our HPLC data showed that, using the optimized conditions obtained in our experiments (20 U/g of cellulase, 50ºC, pH 4.8 and treatment for 8 h), there was a marked transformation from the two glycosides to their aglycons. The anticancer activity was subsequently evaluated using a series of S. baicalensis extracts in which variable lengths of glycosidase treatment time were used. Combining analytical and bioassay results, we observed that the higher the aglycon content, the stronger the antiproliferation effects. Compared to the untransformed control, 8 h of glycosidase catalyzing significantly increased antiproliferative activity on human colorectal and breast cancer cells, and its cancer cell growth inhibition is, in part, mediated by cell cycle arrest at the S-phase and induction of apoptosis. Data from this study suggest that using glycosidase to catalyze S. baicalensis offers a promising approach to increase its anticancer activity. PMID:24026776

YU, CHUNHAO; ZHANG, ZHIYU; ZHANG, HAIJIANG; ZHEN, ZHONG; CALWAY, TYLER; WANG, YUNWEI; YUAN, CHUN-SU; WANG, CHONG-ZHI

2013-01-01

411

Adsorption properties and preparative separation of phenylethanoid glycosides from Cistanche deserticola by use of macroporous resins.  

PubMed

A simple and efficient chromatographic method for large-scale preparative separation of phenylethanoid glycosides (mainly contain echinacoside and acteoside) from Cistanche deserticola was developed. The adsorption properties of eight macroporous resins were evaluated. Three selected resins were further screened depending on the adsorption kinetics curves, in which HPD300 resin showed the best separation efficiency. The adsorption isotherm data on HPD300 resin were fitted to the Freundlich equation in certain concentration range. The dynamic adsorption and desorption experiments were carried out on columns packed with HPD300 resin to optimize the separation process. The breakthrough curves showed that acteoside had a higher affinity to the resin than echinacoside. The contents of echinacoside and acteoside in the product increased from 1.79% and 1.43% in the crude extracts to 16.66% and 15.17%, with recovery yields of 80.41% and 90.17%, respectively. The purity of total phenylethanoid glycosides in the product was 76.58%. PMID:24022055

Liu, Boyan; Ouyang, Jie; Yuan, Xiaofan; Wang, Liwei; Zhao, Bing

2013-10-15

412

Synthesis of solasodine glycoside derivatives and evaluation of their cytotoxic effects on human cancer cells.  

PubMed

Solasodine glycosides, such as solamargine, have been proved to be very important anti-cancer agents. In order to discover more potent cytotoxic agents and explore the preliminary structure activity relationship, a new series of solasodine glycosides 2-9 were synthesized via a transglycosylation strategy, and their cytotoxic activity against a panel of human cancer cell lines (MCF-7, KB, K562, and PC3 cells) were evaluated by MTT assays. The results indicated that compounds 2, 8, and 9 with the substitute moiety of rhamnose, 2-hydroxyethoxymethyl, and 1,3-dihydroxypropan-2-yloxy-methyl, respectively, exhibited quite strong anticancer activity. The underlying mechanism tests demonstrated that these compounds could induce apoptosis detected by DAPI staining, and Annexin V and propidium iodide binding. Cell cycle analysis indicated that the cancer cells were predominantly arrested at the G2/M phase when exposure to these compounds was examined by flow cytometry. These compounds may serve as lead candidates in the development of novel chemotherapeutics for cancer treatment. PMID:22460423

Cui, C Z; Wen, X S; Cui, M; Gao, J; Sun, B; Lou, H X

2012-02-01

413

Isolation and structural elucidation of three new pyridoxine-glycosides in rice bran.  

PubMed

Three new pyridoxine-glycosides were isolated from rice bran (10 kg) as colorless powder by various chromatographic techniques: compound A, 53 mg; compound B, 7.8 mg; compound C, 5.8 mg. Compound A was shown to consist of pyridoxine and glucose in a 1:2 molar ratio by beta-glucosidase hydrolysis, and by 1H-NMR and secondary ion mass spectrometry (SI-MS) data. On partial acid hydrolysis of the compound, cellobiose was liberated. Compound A showed the positive Gibbs color reaction, but the reaction was negative in the presence of boric acid. Thus, compound A was identified as 5'-O-(beta-cellobiosyl)pyridoxine. The 13C-NMR spectral data were compatible with this structure. Compounds B and C were proven to be triglucosides of pyridoxine by enzymic hydrolysis and SI-MS data. From the results of the Gibbs color reaction and partial hydrolyses which yielded compound A, compound B was concluded to be 4'-O-(beta-D-glucosyl)-5'-O-(beta-cellobiosyl)pyridoxine, and compound C to be 5'-O-(beta-glucotriosyl)pyridoxine in which a glucose molecule was bound to the cellobiosyl moiety of compound A through beta-glycosidic linkage. PMID:3141598

Tadera, K; Kaneko, T; Yagi, F

1988-04-01

414

Cyanogenic glycosides in plant-based foods available in New Zealand.  

PubMed

Cyanogenic glycosides occur in a wide range of plant species. The potential toxicity of cyanogenic glycosides arises from enzymatic degradation to produce hydrogen cyanide, which may result in acute cyanide poisoning and has also been implicated in the aetiology of several chronic diseases. One hundred retail foods were sampled and analysed for the presence of total hydrocyanic acid using an acid hydrolysis-isonicotinic/barbituric acid colourimetric method. Food samples included cassava, bamboo shoots, almonds and almond products, pome fruit products, flaxseed/linseed, stone fruit products, lima beans, and various seeds and miscellaneous products, including taro leaves, passion fruit, spinach and canned stuffed vine leaves. The concentrations of total hydrocyanic acid (the hydrocyanic acid equivalents of all cyanogenic compounds) found were consistent with or lower than concentrations reported in the scientific literature. Linseed/flaxseed contained the highest concentrations of total hydrocyanic acid of any of the analysed foods (91-178 mg kg(-1)). Linseed-containing breads were found to contain total hydrocyanic acid at concentrations expected from their linseed content, indicating little impact of processing on the total hydrocyanic acid content. Simulation modelling was used to assess the risk due to the total hydrocyanic acid in fruit juice and linseed-containing bread.  PMID:23984870

Cressey, Peter; Saunders, Darren; Goodman, Janet

2013-01-01

415

HPLC-MSn identification and quantification of flavonol glycosides in 28 wild and cultivated berry species.  

PubMed

Berries and red fruits are rich dietary sources of polyphenols with reported health benefits. More than 50 different flavonols (glycosides of quercetin, myricetin, kaempferol, isorhamnetin, syringetin and laricitrin) have been detected and quantified with HPLC-MS(n) in fruits of blueberry, bilberry, cranberry, lingonberry, eastern shadbush, Japanese wineberry, black mulberry, chokeberry, red, black and white currants, jostaberry, red and white gooseberry, hardy kiwifruit, goji berry, rowan, dog rose, Chinese and midland hawthorn, wild and cultivated species of blackberry, raspberry, strawberry and elderberry. The phenolic constituents and contents varied considerably among the analyzed berry species. Elderberry contained the highest amount of total flavonols (450-568 mgkg(-1) FW), followed by berry species, containing more than 200 mgkg(-1) FW of total: chokeberry (267mgkg(-1)), eastern shadbush (261 mgkg(-1)), wild grown blackberry (260 mgkg(-1)), rowanberry (232 mgkg(-1)), american cranberry (213 mgkg(-1)) and blackcurrants (204 mgkg(-1)). Strawberry (10.5 mgkg(-1)) and white currants (4.5 mgkg(-1)) contained the lowest amount of total flavonols. Quercetins represent the highest percentage (46-100%) among flavonols in most analyzed berries. In wild strawberry and gooseberry the prevailing flavonols belong to the group of isorhamnetins (50-62%) and kaempferols, which represent the major part of flavonols in currants (49-66%). Myricetin glycosides could only be detected in chokeberry, rowanberry and species from the Grossulariaceae, and Adoxaceae family and Vaccinium genus. Wild strawberry and blackberry contained from 3- to 5-fold higher total flavonols than the cultivated one. PMID:22980782

Mikulic-Petkovsek, Maja; Slatnar, Ana; Stampar, Franci; Veberic, Robert

2012-12-15

416

Response surface methodology to optimise Accelerated Solvent Extraction of steviol glycosides from Stevia rebaudiana Bertoni leaves.  

PubMed

Following the approval of steviol glycosides as a food additive in Europe in December 2011, large-scale stevia cultivation will have to be developed within the EU. Thus there is a need to increase the efficiency of stevia evaluation through germplasm enhancement and agronomic improvement programs. To address the need for faster and reproducible sample throughput, conditions for automated extraction of dried stevia leaves using Accelerated Solvent Extraction were optimised. A response surface methodology was used to investigate the influence of three factors: extraction temperature, static time and cycle number on the stevioside and rebaudioside A extraction yields. The model showed that all the factors had an individual influence on the yield. Optimum extraction conditions were set at 100 °C, 4 min and 1 cycle, which yielded 91.8% ± 3.4% of total extractable steviol glycosides analysed. An additional optimisation was achieved by reducing the grind size of the leaves giving a final yield of 100.8% ± 3.3%. PMID:25053094

Jentzer, Jean-Baptiste; Alignan, Marion; Vaca-Garcia, Carlos; Rigal, Luc; Vilarem, Gérard

2015-01-01

417

New flavonol glycosides from the leaves of Triantha japonica and Tofieldia nuda.  

PubMed

Two new flavonol glycosides were isolated from the leaves of Triantha japonica, together with eight known flavonols, kaempferol 3-O-sophoroside, kaempferol 3-O-sambubioside, kaempferol 3-O-glucosyl-(1 --> 2)-[glucosyl-(1 --> 6)-glucoside], quercetin 3-O-sophoroside, quercetin 3-O-sambubioside, isorhamnetin 3-O-glucoside, isorhamnetin 3-O-sophoroside and isorhamnetin 3-O-sambubioside. The new compounds were identified as kaempferol 3-O-beta-xylopyranosyl-(1 --> 2)-[beta-glucopyranosyl-(1 --> 6)-beta-glucopyranoside] (1) and isorhamnetin 3-O-beta-xylopyranosyl-(1 --> 2)-[beta-glucopyranosyl-(1 --> 6)-beta-glucopyranoside] (3) by UV, LC-MS, acid hydrolysis, and 1H and 13C NMR spectroscopy. Another two new flavonol glycosides were isolated from theleaves of Tofieldia nuda, and identified as kaempferol 3-O-beta-glucopyranosyl-(1 --> 2)-[beta-glucopyranosyl-(1 --> 6)-beta-galactopyranoside] (4) and quercetin 3-O-beta-glucopyranosyl-(1 --> 2)-[beta-glucopyranosyl-(1 --> 6)-beta-galactopyranoside] (5). Though the genera Triantha and Tofieldia were treated as Tofieldia sensu lato, they were recently divided into two genera. It was shown by this survey that their flavonoid composition were also different to each other. PMID:24273859

Iwashina, Tsukasa; Tamura, Minoru N; Murai, Yoshinori; Kitajima, Junichi

2013-09-01

418

Rehabilitation of faulty kinetic determinations and misassigned glycoside hydrolase family of retaining mechanism ?-xylosidases.  

PubMed

We obtained Cx1 from a commercial supplier, whose catalog listed it as a ?-xylosidase of glycoside hydrolase family 43. NMR experiments indicate retention of anomeric configuration in its reaction stereochemistry, opposing the assignment of GH43, which follows an inverting mechanism. Partial protein sequencing indicates Cx1 is similar to but not identical to ?-xylosidases of GH52, including Q09LZ0, that have retaining mechanisms. Q09LZ0 ?-xylosidase had been characterized biochemically in kinetic reactions that contained Tris. We overproduced Q09LZ0 and demonstrated that Tris is a competitive inhibitor of the ?-xylosidase. Also, the previous work used grossly incorrect extinction coefficients for product 4-nitrophenol. We redetermined kinetic parameters using reactions that omitted Tris and using correct extinction coefficients for 4-nitrophenol. Cx1 and Q09LZ0 ?-xylosidases were thus shown to possess similar kinetic properties when acting on 4-nitrophenyl-?-d-xylopyranoside and xylobiose. kcat pH profiles of Cx1 and Q09LZ0 acting on 4-nitrophenyl-?-d-xylopyranoside and xylobiose have patterns containing two rate increases with increasing acidity, not reported before for glycoside hydrolases. The dexylosylation step of 4-nitrophenyl-?-d-xylopyranoside hydrolysis mediated by Q09LZ0 is not rate determining for kcat(4NPX). PMID:23916587

Jordan, Douglas B; Vermillion, Karl E; Grigorescu, Arabela A; Braker, Jay D

2013-09-15

419

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. PMID:24431454

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

2014-01-01

420

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

421

Targeted Discovery of Glycoside Hydrolases from a Switchgrass-Adapted Compost Community  

SciTech Connect

Development of cellulosic biofuels from non-food crops is currently an area of intense research interest. Tailoring depolymerizing enzymes to particular feedstocks and pretreatment conditions is one promising avenue of research in this area. Here we added a green-waste compost inoculum to switchgrass (Panicum virgatum) and simulated thermophilic composting in a bioreactor to select for a switchgrass-adapted community and to facilitate targeted discovery of glycoside hydrolases. Smallsubunit (SSU) rRNA-based community profiles revealed that the microbial community changed dramatically between the initial and switchgrass-adapted compost (SAC) with some bacterial populations being enriched over 20-fold. We obtained 225 Mbp of 454-titanium pyrosequence data from the SAC community and conservatively identified 800 genes encoding glycoside hydrolase domains that were biased toward depolymerizing grass cell wall components. Of these, ,10percent were putative cellulasesmostly belonging to families GH5 and GH9. We synthesized two SAC GH9 genes with codon optimization for heterologous expression in Escherichia coli and observed activity for one on carboxymethyl cellulose. The active GH9 enzyme has a temperature optimum of 50uC and pH range of 5.5 to 8 consistent with the composting conditions applied. We demonstrate that microbial communities adapt to switchgrass decomposition using simulated composting condition and that full-length genes can be identified from complex metagenomic sequence data, synthesized and expressed resulting in active enzyme.

Reddy, Amitha; Allgaier, Martin; Park, Joshua I.; Ivanoval, Natalia; Dhaeseleer, Patrik; Lowry, Steve; Sapra, Rajat; Hazen, Terry C.; Simmons, Blake A.; VanderGheynst, Jean S.; Hugenholtz, Philip

2011-05-11

422

The cytotoxic activities of cardiac glycosides from Streptocaulon juventas and the structure-activity relationships.  

PubMed

A series of cardiac glycosides were isolated and identified from the anti-tumor fraction of the root of Streptocaulon juventas in previous studies. In the present research, the cytotoxic activities of the 43 cardiac glycosides on three cell lines, human lung A549 adenocarcinoma cell, large cell lung cancer NCI-H460 cell and normal human fetal lung fibroblast MRC-5 cell, were evaluated in vitro. Most of the tested compounds showed potent inhibitory activities toward the three cell lines. Then, the structure-activity relationships were discussed in detail. It was indicated that hydroxyl and acetyl groups at C-16 increased the activity, whereas hydroxyl group at C-1 and C-5 can both increase and decrease the activity. Two glucosyl groups which were connected by C1'?C6' showed better inhibitory activity against cancer cell lines, while the C1'?C4' connection showed stronger inhibitory activity against the normal cell line. Also, this is the first report that the activities of these compounds exhibited different variation trends between A549 and NCI-H460 cell lines, which indicated that these compounds could selectively inhibit the cell growth. The results would lay a foundation for further research on new anti-tumor drug development. PMID:25128424

Xue, Rui; Han, Na; Ye, Chun; Wang, Lihui; Yang, Jingyu; Wang, Yu; Yin, Jun

2014-10-01

423

Free and glycosidically bound aroma compounds in cherry (Prunus avium L.).  

PubMed

This paper reports the occurrence of both free and glycosidically bound aroma compounds in three sweet cherry cultivars ('Hongdeng', 'Hongyan' and 'Rainier'), with 97 compounds being identified in the three cultivars. The major free volatile compounds found were hexanal, (E)-2-hexenal, (E)-2-hexen-1-ol, benzyl alcohol and benzaldehyde. The major bound volatile compounds found were benzyl alcohol, geraniol, 2-phenylethanol. Also 4-vinylphenol was found in cherry fruit for the first time, and has a relatively high concentration of the glycosidically-bound form in 'Rainier'. Odour activity values (OAVs) were determined for both free and bound volatiles, with 18 compounds having an OAV above 1. The highest OAVs for three cultivars were (E)-?-ionone, hexanal, decanal and (E)-2-hexenal with the highest being over 800 for (E)-?-ionone in 'Honyang'. From these results, it was concluded that the aroma compounds present were similar in all three cultivars, but there was significant variation found in their levels and hence contribution to the aroma of these cultivars. PMID:24444903

Wen, Ya-Qin; He, Fei; Zhu, Bao-Qing; Lan, Yi-Bin; Pan, Qiu-Hong; Li, Chun-You; Reeves, Malcolm J; Wang, Jun

2014-01-01

424

Effects of salt stress on the growth, physiological responses, and glycoside contents of Stevia rebaudiana Bertoni.  

PubMed

This study examined the effects of three different NaCl concentrations (60, 90, and 120 mM) on the growth, physiological responses, and steviol glycoside composition of Stevia rebaudiana Bertoni for 4 weeks. The results showed that the total dry weight decreased by 40% at 120 mM NaCl but remained the same at 60 and 90 mM NaCl. As salt concentration increased, chlorophyll contents decreased markedly by 10-70%, whereas the increments of the antioxidant enzyme activities were 1.0-1.6, 1.2-1.3, and 2.0-4.0 times, respectively, for superoxide dismutase, peroxidase, and catalase. The proline contents in salt-treated plants were 17-42 times higher than that in control. Moreover, leaf possessed significantly higher K? content and K?/Na? ratio than stem and root for all salt treatments. In addition, 90-120 mM NaCl treatment notably decreased the content of rebaudioside A (RA) and stevioside (ST) by 16.2-38.2%, whereas the increment of the ratio of RA/ST of salt-treated plants was 1.1-1.4 times. These results indicate that S. rebaudiana is moderately tolerant to salt stress. Hypohaline soil can be utilized in the plantation of S. rebaudiana and may be profitable for optimizing the steviol glycoside composition. PMID:23711229

Zeng, Jianwei; Chen, Aimeng; Li, Dandan; Yi, Bin; Wu, Wei

2013-06-19

425

Developing effective reverse logistics programs  

Microsoft Academic Search

A recent survey in the automobile aftermarket industry examines reverse logistics practices. The research focuses on two key issues: 1) the influence of program design characteristics, i.e., formalization, returns policy restrictiveness, and innovation, on program performance and 2) the differential influence of making versus buying reverse logistics program software. The results provide guidelines for managerial decisions relating to reverse logistics.

R. Glenn Richey; Haozhe Chen; Stefan E. Genchev; Patricia J. Daugherty

2005-01-01

426

Deobfuscation Reverse Engineering Obfuscated Code  

E-print Network

with the development of obfuscation techniques that are more resilient to straightforward reverse engineering. 1Deobfuscation Reverse Engineering Obfuscated Code Sharath K. Udupa, Saumya K. Debray, Matias Madou, as a step towards reverse engineering such programs. Our results indicate that much of the effects of code

Debray, Saumya

427

Reversible brazing process  

DOEpatents

A method of reversibly brazing surfaces together. An interface is affixed to each surface. The interfaces can be affixed by processes such as mechanical joining, welding, or brazing. The two interfaces are then brazed together using a brazing process that does not defeat the surface to interface joint. Interfaces of materials such as Ni-200 can be affixed to metallic surfaces by welding or by brazing with a first braze alloy. The Ni-200 interfaces can then be brazed together using a second braze alloy. The second braze alloy can be chosen so that it minimally alters the properties of the interfaces to allow multiple braze, heat and disassemble, rebraze cycles.

Pierce, Jim D. (Albuquerque, NM); Stephens, John J. (Albuquerque, NM); Walker, Charles A. (Albuquerque, NM)

1999-01-01

428

Coastally Trapped Wind Reversals  

NSDL National Science Digital Library

This module starts with a forecast scenario that occurs along the California coast. The module then proceeds to describe the structure and climatology of these disturbances, as well as their synoptic and mesoscale evolution. The instruction concludes with a section on forecasting coastally trapped wind reversals. The module also includes a concise summary for quick reference and a final exam to test your knowledge. Like other modules in the Mesoscale Meteorology Primer, this module comes with audio narration, rich graphics, and a companion print version.

Comet

2002-08-06

429

Reversing B cell aging  

PubMed Central

Age-related alterations in the cellular composition of the B lineage are a major cause of the poor antibody response to vaccination and to infectious agents among the elderly population. The mechanisms leading to these changes are poorly understood. Recently, we have shown that these changes reflect, at least in part, homeostatic pressures imposed by long-lived B cells that accumulate with aging, and that aging in the B lineage can be reversed upon alteration of B cell homeostasis by depletion. Here we discuss homeostatic causes for B lineage immunosenescence, and the potential for its rejuvenation. PMID:21483035

Mehr, Ramit; Melamed, Doron

2011-01-01

430

Acaricidal effects of cardiac glycosides, azadirachtin and neem oil against the camel tick, Hyalomma dromedarii (Acari: Ixodidae).  

PubMed

The cardiac glycoside, digitoxin, from Digitalis purpurea L (Scrophulariaceae), a cardiac glycosidal (cardenolide) extract from Calotropis procera (Ait) R Br (Asclepiadaceae), azadirachtin and neem oil from Azadirachta indica A Juss (Meliaceae) were tested for their effects against larvae and adult stages of the camel tick, Hyalomma dromedarii Koch (Acari: Ixodidae). The contact LC50 values of the first three materials against adults were 4.08, 9.63 and >40.7 microg cm(-2), respectively, whereas the dipping LC50 values of the four materials were 409.9, 1096, >5000 and >5000 mg litre(-1), respectively. Contact and dipping LC50 values of the extract and azadirachtin against larvae were 6.16, >20.3 microg cm(-2) and 587.7 and >2500 mg litre(-1), respectively. Azadirachtin had no effects on egg production or feeding of adults up to 5000 mg litre(-1); however at 2500 mg litre(-1), it caused significant reduction in feeding activity of larve, prolonged the period for moulting to nymphal stage, and caused 60% reduction in moultability. Results of the two cardiac glycoside materials are comparable with those of several commercial acaricides. The risks and benefits associated with the use of cardiac glycosides are considered. PMID:14620053

Al-Rajhy, DiefAlla H; Alahmed, Azzam M; Hussein, Hamdy I; Kheir, Salah M

2003-11-01

431

Differential toxicity of a phenolic glycoside from quaking aspen to Papilio glaucus butterfly subspecies, hybrids and backcrosses  

Microsoft Academic Search

Papilio glaucus subspecies, hybrids and backcrosses exhibit greatly different abilities to use quaking aspen (Populus tremuloides) and other members of the Salicaceae as host plants. This study was conducted to test the hypotheses that phenolic glycosides account for the differences in larval performance, and that differential performance is correlated with differential larval esterase activities. To test the hypotheses we conducted

J. Mark Scriber; Richard L. Lindroth; James Nitao

1989-01-01

432

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. PMID:16793926

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

433

Isolation and characterization of five new tetrasaccharide glycosides from the roots of Ipomoea stans and their cytotoxic activity.  

PubMed

Five new tetrasaccharide glycosides, stansins 1-5, were isolated from the roots of Ipomoea stans, and their structures were elucidated using spectroscopic and chemical methods. Preliminary testing showed the cytotoxicity of 5 toward the OVCAR and UISO-SQC-1 cancer cell lines. PMID:15387658

León, Ismael; Enríquez, Raúl G; Gnecco, Dino; Villarreal, María L; Cortés, Daniel Alonso; Reynolds, William F; Yu, Margaret

2004-09-01

434

Efficient activation of armed glycosyl trichloroacetimidates with Sm(OTf) 3 in the stereoselective glycosidation of saccharidic acceptors  

Microsoft Academic Search

Catalytic amounts of Sm(OTf)3 activate armed glycosyl trichloroacetimidates under very mild conditions. This reagent proved effective in promoting the glucosylation of saccharidic acceptors 2, 3, 4, and 5, possessing primary or secondary hydroxyls, with the model donor 1. The stereoselectivity of these glycosidations can be controlled by a suitable choice of solvent.

Matteo Adinolfi; Gaspare Barone; Luigi Guariniello; Alfonso Iadonisi

2000-01-01

435

Determination of six steviol glycosides of Stevia rebaudiana (Bertoni) from different geographical origin by LC-ESI-MS/MS.  

PubMed

Liquid chromatography electro-spray tandem mass spectrometry (LC-ESI/MS/MS) was applied to the determination of sweet glycosides (steviol glycosides), and toxic aglycon steviol in 24 samples of Stevia rebaudiana (Bertoni) aerial parts, which had been experimentally cultivated in Italy, although derived from seeds of different geographical origin. On the basis of the specific fragmentation of these compounds, an LC-MS/MS method was developed with the aim of quantifying analytes in plant material. Although toxic steviol was not detectable in all the samples, the samples with the highest levels of steviol glycosides were identified. Analysis of the different samples revealed that they were good quality samples, quality being directly linked to the presence of sweet glycosides in the plants cultivated in Italy, although there were differences in the content of these compounds according to the origin of the seeds, and in particular, a major concentration of compounds with major sweetness activity and minor toxicity was found in the population coming from Brazil (for example: sample 10, stevioside content 15.74±2.0% p/p and rebaudioside A content 3.09±0.39% p/p of dried plant). Finally, based on this metabolomic targeted approach, the results obtained for the samples were treated by Principal Component Analysis, identifying specific genotypic differences based on the geographic origin of the seeds. PMID:23790843

Montoro, Paola; Molfetta, Ilaria; Maldini, Mariateresa; Ceccarini, Lucia; Piacente, Sonia; Pizza, Cosimo; Macchia, Mario

2013-11-15

436

Cyanuric Chloride as an Efficient Catalyst for the Synthesis of 2,3-Unsaturated O-Glycosides by Ferrier Rearrangement  

PubMed Central

Cyanuric chloride has been found to be an efficient catalyst for the synthesis of 2,3-unsaturated O-glycosides from the reaction of 3,4,6-tri-O-acetyl-D-glucal and a wide range of alcohols in dichloromethane at room temperature. The experimental procedure is simple, and the products are obtained in high yields. PMID:24574881

Yang, Xiaojuan; Li, Na

2014-01-01

437

Reverse Quantum Waves  

NASA Astrophysics Data System (ADS)

As preposterous as it might sound, if quantum waves travel in the reverse direction from subatomic particles, then most of quantum physics can be explained without quantum weirdness or Schr"odinger's cat. Quantum mathematics is unchanged. The diffraction pattern on the screen of the double slit experiment is the same. This proposal is not refuted by the Innsbruck experiments; this is NOT a hidden local variable theory. Research evidence will be presented that is consistent with the idea waves travel in the opposite direction as neutrons. If one's thinking shifts from forwards to backwards quantum waves, the world changes so drastically it is almost unimaginable. Quantum waves move from the mathematical to the real world, multiply in number, and reverse in direction. Wave-particle duality is undone. In the double slit experiment every part of the target screen is emitting such quantum waves in all directions. Some pass through the two slits. Interference occurs on the opposite side of the barrier than is usually imagined. They impinge on ``S'' and an electron is released at random. Because of the interference it is more likely to follow some waves than others. It follows one and only one wave backward; hitting the screen where it's wave originated. )

Boyd, Jeffrey

2010-02-01

438

Advanced Image Reversal Techniques  

NASA Astrophysics Data System (ADS)

Image reversal of a positive photoresist is capable of improving resolution, sidewall angles, and process latitude. Another advantage of an image reversible system is that it produces a negative image by aqueous development. Using novolac resists, we have developed new chemistry which is based on "blocked" reactive agents. The reactive agent can be thermally liberated from the resin, or it can be photochemically generated. After generation, it reacts with the indene carboxylic acid groups in the exposed area to render this area insoluble. After postbake, the resist is flood exposed to convert the remaining photoactive compound in the resist layer; development then gives a negative image of the mask. In one practice of this chemistry, the reactive agent and indene carboxylic acids groups are co-photogenerated. As a result of crosslinking between these two species during processing, the contrast of the photoresist is improved. We call this concept Dual-PAC imaging. Because the crosslinking is a second order reaction based on two photogenerated species, the concentration gradients in the film are sharper than a single-PAC system which follows first order kinetics. The result is an improvement in resolution, cleanout and process latitude as well as contrast.

Taylor, James W.; Brown, Thomas L.; Bassett, David R.

1989-08-01

439

Vascular effects of a soy leaves (Glycine max) extract and kaempferol glycosides in isolated rat carotid arteries.  

PubMed

We have recently purified genistin, and six kaempferol glycosides from a soy leaves ( Glycine max L. Merr.) butanol extract. Here we report the vascular effects of the extract and purified genistin and kaempferol glycosides on contractions induced by different constricting agonists in isolated rat carotid arteries. The butanol extract relaxed artery rings preconstricted by 9,11-dideoxy-11alpha,9alpha-epoxy-methanoprostaglandin F 2 alpha (U46619) or [5 Z,9alpha,11alpha,13 E,15 S]-9,11,15-trihydroxyprosta-5,13-dienoic acid (PGF 2 alpha ) in a dose-dependent manner and this effect was independent of the presence of endothelium. The extract also inhibited the concentration-dependent contraction to U46619 with a slight reduction of the maximal response. The extract produced partial relaxation of both phenylephrine-preconstricted endothelium-intact and -denuded rings. In contrast, the extract had no effect on the contractile response to 50 mM extracellular K (+). None of the six kaempferol glycosides affected vessel tension induced by U46619. A mixture of kaempferol glycosides prepared according to their relative composition in the extract had no effect either. However, kaempferol relaxed U46619- and high K (+)-contracted rings to the same extent. Endothelium played no role in kaempferol-induced relaxation. Genistein induced concentration-dependent relaxation and this effect was attenuated in the endothelium-denuded rings. Genistin caused a smaller relaxant effect. The present results indicate that a butanol extract from soy leaves causes endothelium-independent relaxation in rat carotid artery rings. Kaempferol glycosides, accounting for approximately 48 % of the extract in weight, are not the ingredients responsible for the extract-induced relaxation. Genistein and genistin also caused relaxation, however, the dose range is beyond that of the extract causing relaxation. PMID:12094288

Ho, Hing Man; Chen, Ruoyun; Huang, Yu; Chen, Zhen Yu

2002-06-01

440

Synthesis and biological evaluation of polysulfated oligosaccharide glycosides as inhibitors of angiogenesis and tumor growth.  

PubMed

A series of polysulfated penta- and tetrasaccharide glycosides containing alpha(1-->3)/alpha(1-->2)-linked mannose residues were synthesized as heparan sulfate (HS) mimetics and evaluated for their ability to inhibit angiogenesis. The compounds bound tightly to angiogenic growth factors (FGF-1, FGF-2, and VEGF) and strongly inhibited heparanase activity. In addition, the compounds exhibited potent activity in cell-based and ex vivo assays indicative of angiogenesis, with tetrasaccharides exhibiting activity comparable to that of pentasaccharides. Selected compounds also showed good antitumor activity in vivo in a mouse melanoma (solid tumor) model resistant to the phase III HS mimetic 1 (muparfostat, formerly known as PI-88). The lipophilic modifications also resulted in reduced anticoagulant activity, a common side effect of HS mimetics, and conferred a reasonable pharmacokinetic profile in the rat, as exemplified by the sulfated octyl tetrasaccharide 5. The data support the further investigation of this class of compounds as potential antiangiogenic, anticancer therapeutics. PMID:20128596

Johnstone, Ken D; Karoli, Tomislav; Liu, Ligong; Dredge, Keith; Copeman, Elizabeth; Li, Cai Ping; Davis, Kat; Hammond, Edward; Bytheway, Ian; Kostewicz, Edmund; Chiu, Francis C K; Shackleford, David M; Charman, Susan A; Charman, William N; Harenberg, Job; Gonda, Thomas J; Ferro, Vito

2010-02-25

441

Genetic transformation of foxglove (Digitalis purpurea) by chimeric foreign genes and production of cardioactive glycosides.  

PubMed

The chimeric neo and gus genes on a mini Ti vector are efficiently transferred into the genome of fox glove (Digitalis purpurea L.) using a binary vector system based on a rootinducing Ri plasmid, pRi15834. The transgenic state of established transformed roots was confirmed by Southern blot analysis and by detection of agropine and mannopine. The expression of the chimeric genes controlled by the promoters from TR 1'-2' genes, nos gene and cauliflower mosaic virus 35S RNA was demonstrated by enzymatic and histochemical assays of neomycin phosphotransferase II and ß-glucuronidase. Enzyme-linked immunosorbent assay (ELISA) was carried out using polyclonal antibody reactable against digitoxin to investigate the production of cardenolides. The results of ELISA indicated that the cardioactive glycosides were highly produced in the green transformed hairy roots. PMID:24226593

Saito, K; Yamazaki, M; Shimomura, K; Yoshimatsu, K; Murakoshi, I

1990-07-01

442

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. PMID:19020076

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

443

Structure of Acidothermus cellulolyticus family 74 glycoside hydrolase at 1.82 Å resolution.  

PubMed

Here, a 1.82?Å resolution X-ray structure of a glycoside hydrolase family 74 (GH74) enzyme from Acidothermus cellulolyticus is reported. The resulting structure was refined to an R factor of 0.150 and an Rfree of 0.196. Structural analysis shows that five related structures have been reported with a secondary-structure similarity of between 75 and 89%. The five similar structures were all either Clostridium thermocellum or Geotrichum sp. M128 GH74 xyloglucanases. Structural analysis indicates that the A. cellulolyticus GH74 enzyme is an endoxyloglucanase, as it lacks a characteristic loop that blocks one end of the active site in exoxyloglucanases. Superimposition with the C. thermocellum GH74 shows that Asp451 and Asp38 are the catalytic residues. PMID:24316824

Alahuhta, Markus; Adney, William S; Himmel, Michael E; Lunin, Vladimir V

2013-12-01

444

Preparative isolation and purification of iridoid glycosides from Fructus Corni by high-speed countercurrent chromatography  

PubMed Central

Using a two-phase solvent system composed of dichloromethane–methanol–n-butanol–water–acetic acid (5:5:3:4:0.1, v/v/v/v/v), high-speed countercurrent chromatography was successfully performed for isolation and purification of three iridoid glycosides from Fructus Corni for the first time. From 100 mg of a crude extract of Fructus Corni 7.9 mg of sweroside, 13.1 mg of morroniside, and 10.2 mg of loganin were obtained in less than 3 h with purities of 92.3, 96.3 and 94.2%, respectively. These target compounds were identified by ESI-MS, 1H NMR and 13C NMR. PMID:24899790

Liang, Jinru; He, Jiao; Zhu, Sha; Zhao, Wenna; Zhang, Yongmin; Ito, Yoichiro; Sun, Wenji

2012-01-01

445

Novel Members of Glycoside Hydrolase Family 13 Derived from Environmental DNA?  

PubMed Central

Starch and pullulan-modifying enzymes of the ?-amylase family (glycoside hydrolase family 13) have several industrial applications. To date, most of these enzymes have been derived from isolated organisms. To increase the number of members of this enzyme family, in particular of the thermophilic representatives, we have applied a consensus primer-based approach using DNA from enrichments from geothermal habitats. With this approach, we succeeded in isolating three new enzymes: a neopullulanase and two cyclodextrinases. Both cyclodextrinases displayed significant maltogenic amylase side activity, while one showed significant neopullulanase side activity. Specific motifs and domains that correlated with enzymatic activities were identified; e.g., the presence of the N domain was correlated with cyclodextrinase activity. The enzymes exhibited stability under thermophilic conditions and showed features appropriate for biotechnological applications. PMID:18223106

Labes, Antje; Karlsson, Eva Nordberg; Fridjonsson, Olafur H.; Turner, Pernilla; Hreggvidson, Gudmundur O.; Kristjansson, Jakob K.; Holst, Olle; Schonheit, Peter

2008-01-01

446

Steviol glycosides from Stevia: biosynthesis pathway review and their application in foods and medicine.  

PubMed

Stevia rebaudiana, a perennial herb from the Asteraceae family, is known to the scientific world for its sweetness and steviol glycosides (SGs). SGs are the secondary metabolites responsible for the sweetness of Stevia. They are synthesized by SG biosynthesis pathway operating in the leaves. Most of the genes encoding the enzymes of this pathway have been cloned and characterized from Stevia. Out of various SGs, stevioside and rebaudioside A are the major metabolites. SGs including stevioside have also been synthesized by enzymes and microbial agents. These are non-mutagenic, non-toxic, antimicrobial, and do not show any remarkable side-effects upon consumption. Stevioside has many medical applications and its role against diabetes is most important. SGs have made Stevia an important part of the medicinal world as well as the food and beverage industry. This article presents an overview on Stevia and the importance of SGs. PMID:22823347

Yadav, Sudesh Kumar; Guleria, Praveen

2012-01-01

447

Antioxidative properties of hydroxycinnamic acid derivatives and a phenylpropanoid glycoside. A pulse radiolysis study  

NASA Astrophysics Data System (ADS)

Spectral and redox properties of the phenoxyl radicals from hydroxycinnamic acid derivatives and one selected component of phenylpropanoid glycosides, verbascoside, were studied using pulse radiolysis techniques. On the basis of the pH dependence of phenoxyl radical absorptions, the p Ka values for deprotonation of sinapic acid radical and ferulic acid radical are 4.9 and 5.2. The rate constants of one electron oxidation of those antioxidants by azide radical and bromide radical ion were determined at pH 7. The redox potentials of those antioxidants were determined as 0.59-0.71 V vs NHE at pH 7 with reference standard 4-methoxyphenol and resorcinol.

Lin, Weizhen; Navaratnam, Suppiah; Yao, Side; Lin, Nianyun

1998-10-01

448

Study of Kaempferol Glycoside as an Insulin Mimic Reveals Glycon To Be the Key Active Structure  

PubMed Central

Diabetes mellitus is increasing in prevalence with patient numbers rising throughout the world. Current treatments for diabetes mellitus focus on control of blood glucose levels. Certain kinds of flavonoids or their glycosides stimulate cells to improve glucose uptake and lower blood glucose levels. We synthesized kaempferol 3-O-neohesperidoside (1), a naturally occurring substance present in Cyathea phalerata Mart., reported to mimic the action of insulin. Synthetic 1 promoted glucose uptake in the cultured cell line, L6. Further studies to determine the core structure responsible for this activity using synthetic compounds revealed neohesperidose to be the primary pharmacophore. These findings support the use of certain saccharides as a potential novel treatment for diabetes mellitus by replacing or supporting insulin. PMID:24900249

2010-01-01

449

Expression pattern of glycoside hydrolase genes in Lutzomyia longipalpis reveals key enzymes involved in larval digestion.  

PubMed

The sand fly Lutzomyia longipalpis is the most important vector of American Visceral Leishmaniasis. Adults are phytophagous (males and females) or blood feeders (females only), and larvae feed on solid detritus. Digestion in sand fly larvae has scarcely been studied, but some glycosidase activities putatively involved in microorganism digestion were already described. Nevertheless, the molecular nature of these enzymes, as the corresponding genes and transcripts, were not explored yet. Catabolism of microbial carbohydrates in insects generally involves ?-1,3-glucanases, chitinases, and digestive lysozymes. In this work, the transcripts of digestive ?-1,3-glucanase and chitinases were identified in the L. longipalpis larvae throughout analysis of sequences and expression patterns of glycoside hydrolases families 16, 18, and 22. The activity of one i-type lysozyme was also registered. Interestingly, this lysozyme seems to play a role in immunity, rather than digestion. This is the first attempt to identify the molecular nature of sand fly larval digestive enzymes. PMID:25140153

Moraes, Caroline da Silva; Diaz-Albiter, Hector M; Faria, Maiara do Valle; Sant'Anna, Maurício R V; Dillon, Rod J; Genta, Fernando A

2014-01-01

450

Extraction of iridoid glycosides and their determination by micellar electrokinetic capillary chromatography.  

PubMed

Several methods for the extraction of two iridoid glycosides, catalpol and aucubin, from the plant matrix (Veronica longifolia leaves) were compared. Pressurized hot water extraction and hot water extraction were the most efficient isolation techniques for both. Pressurized liquid extraction and maceration with various organic solvents were also tested. Relative to the amounts extracted with hot water, ethanol extracted only 22% of catalpol and 25% of aucubin and pressurized hot water extracted 83% of catalpol and 92% of aucubin. The lowest relative standard deviations, 22% for catalpol and 8% for aucubin, were achieved with hot water extraction (13 repetitions), and the highest relative standard deviations, 76% for catalpol and 73% for aucubin, with pressurized liquid extraction (five repetitions). A fast capillary electrophoretic method was developed for the quantitative determination of catalpol and aucubin. PMID:10677081

Suomi, J; Sirén, H; Hartonen, K; Riekkola, M L

2000-01-28

451

Coumarin glycosides and iridoid glucosides with neuroprotective effects from Hydrangea paniculata.  

PubMed

Five new coumarin glycosides, umbelliferone 7-O-sophoroside (1), umbelliferone 7-O-?-D-glucopyranosyl(1???3)-?-D-glucopyranoside (2), umbelliferone 7-O-?-D-glucopyranosyl(1???3)-[?-D-apiofuranosyl(1???6)]-?-D-glucopyranoside (3), umbelliferone 7-O-?-D-glucopyranosyl(1???2)-?-D-apiofuranosyl(1???6)-?-D-glucopyranoside (4), and umbelliferone 7-O-?-D-glucopyranosyl(1???5)-?-D-apiofuranosyl(1???6)-?-D-glucopyranoside (5), and two new iridoid glucosides, 7-O-E-isoferuloyl loganic acid (6) and 7-O-?-D-glucopyranosyl loganin (7), together with eight known compounds (8-15) were isolated from the stems of Hydrangea paniculata. Their structures were established by spectroscopic analysis and chemical methods. At 10?µM, compounds 1, 3, 5, 6, 8, 9, and 13 showed neuroprotective effects against serum deprivation-induced PC12 cell damage. PMID:23047248

Shi, Jing; Li, Chuang-Jun; Yang, Jing-Zhi; Yuan, Yu-He; Chen, Nai-Hong; Zhang, Dong-Ming

2012-11-01

452

Stereoselective C-glycosidation of D-fucose derivatives directed by the protective groups.  

PubMed

Stereoselectivity in the C-glycosidation of lactones derived from D-fucose by following Kishi's method, which involves the addition of a nucleophile onto a carbohydrate-derived lactone and subsequent reduction of the lactol, was found to be reliant on the nature of the C2 and C3 protective groups. Lactones bearing TBDMS protecting groups selectively afford 1,3-trans products (? anomer), in which the stereoselective outcome is in apparent concordance with Woerpel's model. On the other hand, their benzylated congeners produce the 1,3-cis products (? anomer) as the major diastereoisomers. The latter results suggest an abnormal behavior during the stereoselective nucleophilic substitution at the anomeric position of the benzylated lactones. PMID:24893263

Cortezano-Arellano, Omar; Meléndez-Becerra, Camilo A; Cortés, Fernando; Sartillo-Piscil, Fernando; Cordero-Vargas, Alejandro

2014-07-01

453

Inhibitory effects of Citrus hassaku extract and its flavanone glycosides on melanogenesis.  

PubMed

The 50% ethanolic extract (CH-ext) obtained from the unripe fruit of Citrus hassaku exhibited significant tyrosinase inhibitory activity. The CH-ext showed antioxidant activity, such as superoxide dismutase (SOD)-like activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Activity-guided fractionation of the CH-ext indicated that flavanone glycoside-rich fractions showed potent tyrosinase inhibitory activity. Further examination revealed that the tyrosinase inhibitory activity and antioxidant activity of the CH-ext were attributable to naringin and neohesperidin, respectively. The CH-ext showed inhibition of melanogenesis without any effects on cell proliferation in cultured murine B16 melanoma cells after glucosamine exposure. The topical application of the CH-ext to the dorsal skin of brownish guinea pigs showed in vivo preventive effects against UVB-induced pigmentation. PMID:19252287

Itoh, Kimihisa; Hirata, Noriko; Masuda, Megumi; Naruto, Shunsuke; Murata, Kazuya; Wakabayashi, Keitaro; Matsuda, Hideaki

2009-03-01

454

Enzymatic acylation of flavonoid glycosides by a carbohydrate esterase of family 16.  

PubMed

The acetyl esterase of Trichoderma reesei belonging to carbohydrate esterase (CE) family 16 catalyzes transacylations to carbohydrate moieties of flavonoid glycosides, esculin and rutin. The enzyme recognizes as acyl donors vinyl esters of short carboxylic acids. Esculin was acylated at position 3 of the glucosyl residue in aqueous solutions saturated with vinyl acetate and vinyl propionate. The yields of esculin monoacetate and monopropionate of esculin in aqueous medium (esculin 40 mM, enzyme 40 µg/ml, 40 °C, 3 days) were 67 and 55 %, respectively. Replacement of water by 2-propanol was required for a similar acylation of rutin at 4 mM concentration. The yields of rutin monoacetate and propionate were 60 and 30 %, respectively. The results indicate that the enzyme could be used for an easy modification of solubility and hydrophobicity of glycosylated compounds, including drugs and functional food additives. PMID:25048225

Biely, Peter; Cziszárová, Mária; Wong, Ken K Y; Fernyhough, Alan

2014-11-01

455

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

456

Immunochemical authentication of manuka honey using a monoclonal antibody specific to a glycoside of methyl syringate.  

PubMed

Leptosperin, a novel glycoside of methyl syringate, is exclusively present in manuka honey derived from the Leptospermum species Leptospermum scoparium. Quantification of leptosperin might thus be applicable for authentication of honey. The concentration of leptosperin has high linearity with antibacterial activity. We established a monoclonal antibody to leptosperin and characterized the antibody in detail by a competitive enzyme-linked immunosorbent assay (ELISA), comparing the results with those of the high-performance liquid chromatography (HPLC) method for validation. The antigen in manuka honey was confirmed as leptosperin by HPLC fractionation with quantitation by an ELISA. Leptosperin contents of 50 honey samples were analyzed by an established ELISA, which can handle 20 samples (duplicate) on one 96-well plate. Significant coincidence with the chemical quantitation was observed. Immunochemical quantitation of leptosperin would be an economical and facile method for the possible authentication of manuka honey, allowing many honey samples to be processed and analyzed by an ELISA simultaneously. PMID:25310890

Kato, Yoji; Araki, Yukako; Juri, Maki; Fujinaka, Rie; Ishisaka, Akari; Kitamoto, Noritoshi; Nitta, Yoko; Niwa, Toshio; Takimoto, Yosuke

2014-11-01

457

Expression pattern of glycoside hydrolase genes in Lutzomyia longipalpis reveals key enzymes involved in larval digestion  

PubMed Central

The sand fly Lutzomyia longipalpis is the most important vector of American Visceral Leishmaniasis. Adults are phytophagous (males and females) or blood feeders (females only), and larvae feed on solid detritus. Digestion in sand fly larvae has scarcely been studied, but some glycosidase activities putatively involved in microorganism digestion were already described. Nevertheless, the molecular nature of these enzymes, as the corresponding genes and transcripts, were not explored yet. Catabolism of microbial carbohydrates in insects generally involves ?-1,3-glucanases, chitinases, and digestive lysozymes. In this work, the transcripts of digestive ?-1,3-glucanase and chitinases were identified in the L. longipalpis larvae throughout analysis of sequences and expression patterns of glycoside hydrolases families 16, 18, and 22. The activity of one i-type lysozyme was also registered. Interestingly, this lysozyme seems to play a role in immunity, rather than digestion. This is the first attempt to identify the molecular nature of sand fly larval digestive enzymes. PMID:25140153

Moraes, Caroline da Silva; Diaz-Albiter, Hector M.; Faria, Maiara do Valle; Sant'Anna, Mauricio R. V.; Dillon, Rod J.; Genta, Fernando A.

2014-01-01

458

Effects of S. officinalis L. radix triterpene glycosides on innate immunity factors.  

PubMed

The effects of triterpene glycosides (saponins) extracted from Saponaria officinalis L. radices, on the cellular and humoral innate immunity factors were studied. Saponins stimulated the phagocytic, bactericidal, and adhesion activities of polymorphonuclear leukocytes. Optimal conditions of saponin treatment (dose and duration) were determined for mice. Saponins promoted the maturation of human peripheral blood dendritic cells, which was proven by high expression of CD83 (terminal differentiation marker) and CD86 (bone-stimulating molecule) and of HLA-DR and HLA-ABC molecules on the cell membrane. Saponins modulated the production of TNF-?, IL-1?, IL-4, IL-6, and IFN-? in cultured peripheral blood intact cells. The results help to understand some mechanisms of the effects of saponins extracted from Saponaria officinalis L. radix on the cellular and humoral factors of innate immunity and demonstrate good prospects of their practical use. PMID:24771377

Kuznetsova, T A; Ivanushko, L A; Makarenkova, I D; Cherevach, E I; Ten'kovskaya, L A

2014-01-01

459

A reversible molecular valve  

PubMed Central

In everyday life, a macroscopic valve is a device with a movable control element that regulates the flow of gases or liquids by blocking and opening passageways. Construction of such a device on the nanoscale level requires (i) suitably proportioned movable control elements, (ii) a method for operating them on demand, and (iii) appropriately sized passageways. These three conditions can be fulfilled by attaching organic, mechanically interlocked, linear motor molecules that can be operated under chemical, electrical, or optical stimuli to stable inorganic porous frameworks (i.e., by self-assembling organic machinery on top of an inorganic chassis). In this article, we demonstrate a reversibly operating nanovalve that can be turned on and off by redox chemistry. It traps and releases molecules from a maze of nanoscopic passageways in silica by controlling the operation of redox-activated bistable [2]rotaxane molecules tethered to the openings of nanopores leading out of a nanoscale reservoir. PMID:16006520

Nguyen, Thoi D.; Tseng, Hsian-Rong; Celestre, Paul C.; Flood, Amar H.; Liu, Yi; Stoddart, J. Fraser; Zink, Jeffrey I.

2005-01-01

460

Reverse Osmosis Optimization  

SciTech Connect

This technology evaluation was prepared by Pacific Northwest National Laboratory on behalf of the U.S. Department of Energy’s Federal Energy Management Program (FEMP). ¬The technology evaluation assesses techniques for optimizing reverse osmosis (RO) systems to increase RO system performance and water efficiency. This evaluation provides a general description of RO systems, the influence of RO systems on water use, and key areas where RO systems can be optimized to reduce water and energy consumption. The evaluation is intended to help facility managers at Federal sites understand the basic concepts of the RO process and system optimization options, enabling them to make informed decisions during the system design process for either new projects or recommissioning of existing equipment. This evaluation is focused on commercial-sized RO systems generally treating more than 80 gallons per hour.¬

McMordie-Stoughton, Katherine L.; Duan, Xiaoli; Wendel, Emily M.

2013-08-26

461

Reverse photoacoustic standoff spectroscopy  

SciTech Connect

A system and method are disclosed for generating a reversed photoacoustic spectrum at a greater distance. A source may emit a beam to a target and a detector measures signals generated as a result of the beam being emitted on the target. By emitting a chopped/pulsed light beam to the target, it may be possible to determine the target's optical absorbance by monitoring the intensity of light collected at the detector at different wavelengths. As the wavelength of light is changed, the target may absorb or reject each optical frequency. Rejection may increase the intensity at the sensing element and absorption may decrease the intensity. Accordingly, an identifying spectrum of the target may be made with the intensity variation of the detector as a function of illuminating wavelength.

Van Neste, Charles W. (Kingston, TN); Senesac, Lawrence R. (Knoxville, TN); Thundat, Thomas G. (Knoxville, TN)

2011-04-12

462

Properly apply reverse osmosis  

SciTech Connect

Reverse osmosis (RO) is a water purification technique used to reduce the loading of dissolved solids in solution. The popularity of RO for treating boiler feedwater is growing because of the rising cost of ion-exchange-based demineralization as well as safety concerns associated with handling acid and caustic. A properly designed and operated RO-based boiler-feedwater-treatment system can reduce the load to, and costs associated with, ion exchange demineralization. This article discusses RO feedwater quality recommendations, pretreatment techniques, and system monitoring necessary to achieve optimum RO system performance in the most cost-effective manner. Regardless of the application--whether it is the treatment of boiler feedwater, industrial wastewater, or process water--the approach to pretreatment and the other design and operating guidance offered here remains the same.

Kucera, J.

1997-02-01

463

Reverse slapper detonator  

DOEpatents

A reverse slapper detonator (70), and methodology related thereto, are provided. The detonator (70) is adapted to be driven by a pulse of electric power from an external source (80). A conductor (20) is disposed along the top (14), side (18), and bottom (16) surfaces of a sheetlike insulator (12). Part of the conductor (20) comprises a bridge (28), and an aperture (30) is positioned within the conductor (20), with the bridge (28) and the aperture (30) located on opposite sides of the insulator (12). A barrel (40) and related explosive charge (50) are positioned adjacent to and in alignment with the aperture (30), and the bridge (28) is buttressed with a backing layer (60). When the electric power pulse vaporizes the bridge (28), a portion of the insulator (12) is propelled through the aperture (30) and barrel (40), and against the explosive charge (50), thereby detonating it.

Weingart, Richard C. (Livermore, CA)

1990-01-01

464

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. PMID:1254642

Villegas, GM; Villegas, J

1976-01-01

465

Construction of a rice glycoside hydrolase phylogenomic database and identification of targets for biofuel research  

PubMed Central

Glycoside hydrolases (GH) catalyze the hydrolysis of glycosidic bonds in cell wall polymers and can have major effects on cell wall architecture. Taking advantage of the massive datasets available in public databases, we have constructed a rice phylogenomic database of GHs (http://ricephylogenomics.ucdavis.edu/cellwalls/gh/). This database integrates multiple data types including the structural features, orthologous relationships, mutant availability, and gene expression patterns for each GH family in a phylogenomic context. The rice genome encodes 437 GH genes classified into 34 families. Based on pairwise comparison with eight dicot and four monocot genomes, we identified 138 GH genes that are highly diverged between monocots and dicots, 57 of which have diverged further in rice as compared with four monocot genomes scanned in this study. Chromosomal localization and expression analysis suggest a role for both whole-genome and localized gene duplications in expansion and diversification of GH families in rice. We examined the meta-profiles of expression patterns of GH genes in twenty different anatomical tissues of rice. Transcripts of 51 genes exhibit tissue or developmental stage-preferential expression, whereas, seventeen other genes preferentially accumulate in actively growing tissues. When queried in RiceNet, a probabilistic functional gene network that facilitates functional gene predictions, nine out of seventeen genes form a regulatory network with the well-characterized genes involved in biosynthesis of cell wall polymers including cellulose synthase and cellulose synthase-like genes of rice. Two-thirds of the GH genes in rice are up regulated in response to biotic and abiotic stress treatments indicating a role in stress adaptation. Our analyses identify potential GH targets for cell wall modification. PMID:23986771

Sharma, Rita; Cao, Peijian; Jung, Ki-Hong; Sharma, Manoj K.; Ronald, Pamela C.

2013-01-01

466

Structural Relationships in the Lysozyme Superfamily: Significant Evidence for Glycoside Hydrolase Signature Motifs  

PubMed Central

Background Chitin is a polysaccharide that forms the hard, outer shell of arthropods and the cell walls of fungi and some algae. Peptidoglycan is a polymer of sugars and amino acids constituting the cell walls of most bacteria. Enzymes that are able to hydrolyze these cell membrane polymers generally play important roles for protecting plants and animals against infection with insects and pathogens. A particular group of such glycoside hydrolase enzymes share some common features in their three-dimensional structure and in their molecular mechanism, forming the lysozyme superfamily. Results Besides having a similar fold, all known catalytic domains of glycoside hydrolase proteins of lysozyme superfamily (families and subfamilies GH19, GH22, GH23, GH24 and GH46) share in common two structural elements: the central helix of the all-? domain, which invariably contains the catalytic glutamate residue acting as general-acid catalyst, and a ?-hairpin pointed towards the substrate binding cleft. The invariant ?-hairpin structure is interestingly found to display the highest amino acid conservation in aligned sequences of a given family, thereby allowing to define signature motifs for each GH family. Most of such signature motifs are found to have promising performances for searching sequence databases. Our structural analysis further indicates that the GH motifs participate in enzymatic catalysis essentially by containing the catalytic water positioning residue of inverting mechanism. Conclusions The seven families and subfamilies of the lysozyme superfamily all have in common a ?-hairpin structure which displays a family-specific sequence motif. These GH ?-hairpin motifs contain potentially important residues for the catalytic activity, thereby suggesting the participation of the GH motif to catalysis and also revealing a common catalytic scheme utilized by enzymes of the lysozyme superfamily. PMID:21085702

Wohlkonig, Alexandre; Huet, Joelle; Looze, Yvan; Wintjens, Rene

2010-01-01

467

Antioxidant Activities of Extract and Fractions from Receptaculum Nelumbinis and Related Flavonol Glycosides  

PubMed Central

The antioxidant activities of ethanolic crude extract (ECE) and its four different solvent sub-fractions (namely, petroleum ether fraction (PEF), ethyl acetate fraction (EAF), n-butanol fraction (BF) and the aqueous fraction (AF) from the receptacles of Nelumbo nucifera Gaertn. (Receptaculum Nelumbinis) were investigated using two in vitro antioxidant assays. BF showed the highest total phenolic content (607.6 mg/g gallic acid equivalents), total flavonoid content (862.7 mg/g rutin equivalents) and total proanthocyanidin content (331.0 mg/g catechin equivalents), accompanied with the highest antioxidant activity compared to other fractions through 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2?-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. Five flavonol glycosides, namely hyperoside (1), isoquercitrin (2), quercetin-3-O-?-d-glucuronide (3), isorhamnetin-3-O-?-d-galactoside (4) and syringetin-3-O-?-d-glucoside (5) were isolated from the Receptaculum Nelumbinis. Compounds 2–5 were isolated for the first time from the Receptaculum Nelumbinis. The five isolated flavone glycosides, particularly compounds 1–3, demonstrated significant DPPH and ABTS radical scavenging activity, with IC50 values of 8.9 ± 0.2, 5.2 ± 0.2, 7.5 ± 0.1 for DPPH and 114.2 ± 1.7, 112.8 ± 0.8, 172.5 ± 0.7 ?g/mL for ABTS, respectively. These results suggest that Receptaculum Nelumbinis has strong antioxidant potential and may be potentially used as a safe and inexpensive bioactive source of natural antioxidants. PMID:22837685

Wu, Yan-Bin; Zheng, Li-Jun; Wu, Jian-Guo; Chen, Ti-Qiang; Yi, Jun; Wu, Jin-Zhong

2012-01-01

468