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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

Multidrug resistance-reversal effects of resin glycosides from Dichondra repens.  

PubMed

Investigation of hydrophobic extract of Dichondra repens (Convolvulaceae) led to the isolation of three new resin glycosides dichondrins A-C (1-3), and three known resin glycosides cus-1, cus-2, and cuse 3. All the isolated resin glycosides with an acyclic core were evaluated for their multidrug resistance reversal activities, and the combined use of these compounds at a concentration of 25?M increased the cytotoxicity of vincristine by 1.03-1.78-fold. PMID:25597010

Song, Wei-Bin; Wang, Wen-Qiong; Zhang, Shu-Wei; Xuan, Li-Jiang

2015-02-15

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

'Peony Nebula' Star Settles for Silver Medal  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Poster Version Movie

If our galaxy, the Milky Way, were to host its own version of the Olympics, the title for the brightest known star would go to a massive star called Eta Carina. However, a new runner-up now the second-brightest star in our galaxy has been discovered in the galaxy's dusty and frenzied interior. This image from NASA's Spitzer Space Telescope shows the new silver medalist, circled in the inset above, in the central region of our Milky Way.

Dubbed the 'Peony nebula' star, this blazing ball of gas shines with the equivalent light of 3.2 million suns. The reigning champ, Eta Carina, produces the equivalent of 4.7 million suns worth of light though astronomers say these estimates are uncertain, and it's possible that the Peony nebula star could be even brighter than Eta Carina.

If the Peony star is so bright, why doesn't it stand out more in this view? The answer is dust. This star is located in a very dusty region jam packed with stars. In fact, there could be other super bright stars still hidden deep in the stellar crowd. Spitzer's infrared eyes allowed it to pierce the dust and assess the Peony nebula star's true brightness. Likewise, infrared data from the European Southern Observatory's New Technology Telescope in Chile were integral in calculating the Peony nebula star's luminosity.

The Peony nebula, which surrounds the Peony nebular star, is the reddish cloud of dust in and around the white circle.

The movie begins by showing a stretch of the dusty and frenzied central region of our Milky Way galaxy. It then zooms in to reveal the 'Peony nebula' star the new second-brightest star in the Milky Way, discovered in part by NASA's Spitzer Space Telescope.

This is a three-color composite showing infrared observations from two Spitzer instruments. Blue represents 3.6-micron light and green shows light of 8 microns, both captured by Spitzer's infrared array camera. Red is 24-micron light detected by Spitzer's multiband imaging photometer.

2008-01-01

5

Novel reversion reaction of D-arabino-hexose phenylosotriazole. A useful model in natural glycoside and polysaccharide analysis.  

PubMed

Treatment of D-arabino-hexose phenylosotriazole with conc. hydrochloric acid afforded a new type of alpha- and beta-glycosides of D-erythrose formed by reaction of the 3,6-anhydro derivative with the in situ formed 2-phenyl-4-(formylmethyl)- 1,2,3-triazole. PMID:11580194

Hassan, H H; El-Husseiny, A H

2001-09-01

6

First Report of Tobacco Rattle Virus in Peony in Alaska  

Technology Transfer Automated Retrieval System (TEKTRAN)

In 2007, scattered peony (Paeonia lactiflora ‘Sarah Bernhardt’) plants cultivated on plots at the University of Alaska Experimental Station in Fairbanks, Alaska, contained distinct leaf ringspot patterns. Leaf samples from symptomatic plants were collected in early July (6 plants) and late September...

7

Preparative purification of peoniflorin and albiflorin from peony rhizome using macroporous resin and medium-pressure liquid chromatography.  

PubMed

Peoniflorin (PF) and albiflorin (AF) are two principal components of Paeonia species, which exhibit various biological activities such as improvement of blood circulation and immunoregulating function. To further utilization of waste parts of peony plants, an efficient method for preparative purification of these two ingredients from white peony rhizome was developed based on macroporous resin (MAR) and medium-pressure liquid chromatography (MPLC). The separation characteristics of nine typical MARs were investigated by static adsorption/desorption experiments, and LX38 was revealed as optimal one. Further static experiments with LX38 resin indicated that the adsorbents fitted well to the pseudo-second-order kinetics model and both Langmuir and Freundlich isotherm models. Based on the optimal process parameters, a large-scale preparation was successfully applied. After one run treatment with LX38, the contents of PF and AF were increased 15-fold to 24.5 and 16.8% in the refined extract, respectively. Both purified compounds were obtained from refined extract by reversed-phase MPLC at second-stage separation. The process developed is better because of its low cost, high efficiency, and procedural simplicity making it a potential approach for large-scale production of PF and AF for their further applications in functional foods and pharmaceuticals. PMID:22674837

Wang, Rong; Peng, Xiaoguo; Wang, Liming; Tan, Beibei; Liu, Jiangyun; Feng, Yulin; Yang, Shilin

2012-08-01

8

Rapid microsatellite development for tree peony and its implications  

PubMed Central

Background Microsatellites are ubiquitous in genomes of various organisms. With the realization that they play roles in developmental and physiological processes, rather than exist as ‘junk’ DNA, microsatellites are receiving increasing attention. Next-generation sequencing allows acquisition of large-scale microsatellite information, and is especially useful for plants without reference genome sequences. Results In this study, enriched DNA libraries of tree peony, a well-known ornamental woody shrub, were used for high-throughput microsatellite development by 454 GS-FLX Titanium pyrosequencing. We obtained 675,221 reads with an average length of 356 bp. The total size of examined sequences was 240,672,018 bp, from which 237,134 SSRs were identified. Of these sequences, 164,043 contained SSRs, with 27% featuring more than one SSR. Interestingly, a high proportion of SSRs (43%) were present in compound formation. SSRs with repeat motifs of 1–4 bp (mono-, di-, tri-, and tetra-nucleotide repeats) accounted for 99.8% of SSRs. Di-nucleotide repeats were the most abundant. As in most plants, the predominant motif in tree peony was (A/T)n, with (G/C)n less common. The lengths of SSRs were classified into 11 groups. The shortest SSRs (10 bp) represented 1% of the total number, whereas SSRs 21–30 and 101–110 bp long accounted for 26% and 29%, respectively, of all SSRs. Many sequences (42,111) were mapped to CDS (coding domain sequence) regions using Arabidopsis as a reference. GO annotation analysis predicted that CDSs with SSRs performed various functions associated with cellular components, molecular functions, and biological processes. Of 100 validated primer pairs, 24 were selected for polymorphism analysis among 23 genotypes; cluster analysis of the resulting data grouped genotypes according to known relationships, confirming the usefulness of the developed SSR markers. Conclusions The results of our large-scale SSR marker development using tree peony are valuable for investigating plant genomic structural evolution and elucidating phenotypic variation in this species during its evolution and artificial selection. The newly identified SSRs should be useful for genetic linkage map construction, QTL mapping, gene location and cloning, and molecular marker-assisted breeding. In addition, the genome-wide marker resources generated in this study should aid genomic studies of tree peony and related species. PMID:24341681

2013-01-01

9

Changes in soil microbial community structure with planting years and cultivars of tree peony (Paeonia suffruticosa).  

PubMed

To understand the effects of planting tree peony (Paeonia suffruticosa) on soil microbial community structure, soil samples were collected from the tree peony gardens with three peony cultivars and three planting years, and adjacent wasteland at Luoyang, Henan Province of China. Soil microbial communities were analyzed by the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) of partial 16S rDNA and sequencing methods. With the succeeding development of tree peony garden ecosystems, soil pH, organic C, total P, and available P increased. Soil total N, the cell numbers of bacteria, fungi, and actinomycetes, the Shannon's diversity index (H), richness (S), and Evenness (E(H)) first showed an increasing trend after wasteland was reclaimed and then a decreasing trend became apparent after 5 years of planting. Principal component analysis based on DGGE banding patterns showed that the microbial community structures were influenced by tree peony cultivars and planting years, and the influences of planting years were greater than those of tree peony cultivars. Sequence analysis of the DGGE bands revealed that the dominant bacteria in tree peony garden soils belonged to Proteobacteria, Bacteroidetes, Actinobacteria, Firmicutes, Acidobacteria, Planctomycetes, Euryarchaeota, and Unclassified-bacteria. Moreover, some bacteria closely related to Bradyrhizobium, Sphingopyxis, Novosphingobium, and Sphingomonas, which have been associated with nitrogen fixation and recalcitrant compounds degradation, disappeared with the increasing planting years of tree peony. The bacteria had similarity of 100% compared with Pseudomonas mandelii which was a denitrifying bacteria, and increased gradually with increasing planting years of tree peony. PMID:23933807

Xue, Dong; Huang, Xiangdong

2014-02-01

10

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

PubMed

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

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

2014-06-15

11

Multiple species of wild tree peonies gave rise to the ‘king of flowers’, Paeonia suffruticosa Andrews  

PubMed Central

The origin of cultivated tree peonies, known as the ‘king of flowers' in China for more than 1000 years, has attracted considerable interest, but remained unsolved. Here, we conducted phylogenetic analyses of explicitly sampled traditional cultivars of tree peonies and all wild species from the shrubby section Moutan of the genus Paeonia based on sequences of 14 fast-evolved chloroplast regions and 25 presumably single-copy nuclear markers identified from RNA-seq data. The phylogeny of the wild species inferred from the nuclear markers was fully resolved and largely congruent with morphology and classification. The incongruence between the nuclear and chloroplast trees suggested that there had been gene flow between the wild species. The comparison of nuclear and chloroplast phylogenies including cultivars showed that the cultivated tree peonies originated from homoploid hybridization among five wild species. Since the origin, thousands of cultivated varieties have spread worldwide, whereas four parental species are currently endangered or on the verge of extinction. The documentation of extensive homoploid hybridization involved in tree peony domestication provides new insights into the mechanisms underlying the origins of garden ornamentals and the way of preserving natural genetic resources through domestication. PMID:25377453

Zhou, Shi-Liang; Zou, Xin-Hui; Zhou, Zhi-Qin; Liu, Jing; Xu, Chao; Yu, Jing; Wang, Qiang; Zhang, Da-Ming; Wang, Xiao-Quan; Ge, Song; Sang, Tao; Pan, Kai-Yu; Hong, De-Yuan

2014-01-01

12

Multiple species of wild tree peonies gave rise to the 'king of flowers', Paeonia suffruticosa Andrews.  

PubMed

The origin of cultivated tree peonies, known as the 'king of flowers' in China for more than 1000 years, has attracted considerable interest, but remained unsolved. Here, we conducted phylogenetic analyses of explicitly sampled traditional cultivars of tree peonies and all wild species from the shrubby section Moutan of the genus Paeonia based on sequences of 14 fast-evolved chloroplast regions and 25 presumably single-copy nuclear markers identified from RNA-seq data. The phylogeny of the wild species inferred from the nuclear markers was fully resolved and largely congruent with morphology and classification. The incongruence between the nuclear and chloroplast trees suggested that there had been gene flow between the wild species. The comparison of nuclear and chloroplast phylogenies including cultivars showed that the cultivated tree peonies originated from homoploid hybridization among five wild species. Since the origin, thousands of cultivated varieties have spread worldwide, whereas four parental species are currently endangered or on the verge of extinction. The documentation of extensive homoploid hybridization involved in tree peony domestication provides new insights into the mechanisms underlying the origins of garden ornamentals and the way of preserving natural genetic resources through domestication. PMID:25377453

Zhou, Shi-Liang; Zou, Xin-Hui; Zhou, Zhi-Qin; Liu, Jing; Xu, Chao; Yu, Jing; Wang, Qiang; Zhang, Da-Ming; Wang, Xiao-Quan; Ge, Song; Sang, Tao; Pan, Kai-Yu; Hong, De-Yuan

2014-12-22

13

Effect of Calcium Sprays on Mechanical Strength and Cell Wall Fractions of Herbaceous Peony (Paeonia Lactiflora Pall.) Inflorescence Stems  

PubMed Central

Calcium is an essential element and imparts significant structural rigidity to the plant cell walls, which provide the main mechanical support to the entire plant. In order to increase the mechanical strength of the inflorescence stems of herbaceous peony, the stems are treated with calcium chloride. The results shows that preharvest sprays with 4% (w/v) calcium chloride three times after bud emergence are the best at strengthening “Da Fugui” peonies’ stems. Calcium sprays increased the concentrations of endogenous calcium, total pectin content as well as cell wall fractions in herbaceous peonies stems, and significantly increased the contents of them in the top segment. Correlation analysis showed that the breaking force of the top segment of peonies’ stems was positively correlated with the ratio of water insoluble pectin to water soluble pectin (R = 0.673) as well as lignin contents (R = 0.926) after calcium applications. PMID:22606005

Li, Chengzhong; Tao, Jun; Zhao, Daqiu; You, Chao; Ge, Jintao

2012-01-01

14

Determination of eight artificial sweeteners and common Stevia rebaudiana glycosides in non-alcoholic and alcoholic beverages by reversed-phase liquid chromatography coupled with tandem mass spectrometry.  

PubMed

The method for the determination of acesulfame-K, saccharine, cyclamate, aspartame, sucralose, alitame, neohesperidin dihydrochalcone, neotame and five common steviol glycosides (rebaudioside A, rebaudioside C, steviol, steviolbioside and stevioside) in soft and alcoholic beverages was developed using high-performance liquid chromatography and tandem mass spectrometry with electrospray ionisation (HPLC-ESI-MS/MS). To the best of our knowledge, this is the first work that presents an HPLC-ESI-MS/MS method which allows for the simultaneous determination of all EU-authorised high-potency sweeteners (thaumatin being the only exception) in one analytical run. The minimalistic sample preparation procedure consisted of only two operations; dilution and centrifugation. Linearity, limits of detection and quantitation, repeatability, and trueness of the method were evaluated. The obtained recoveries at three tested concentration levels varied from 97.0 to 105.7 %, with relative standard deviations lower than 4.1 %. The proposed method was successfully applied for the determination of sweeteners in 24 samples of different soft and alcoholic drinks. PMID:25471292

Kubica, Pawe?; Namie?nik, Jacek; Wasik, Andrzej

2014-12-01

15

Determination of chemical variability of phenolic and monoterpene glycosides in the seeds of Paeonia species using HPLC and profiling analysis.  

PubMed

A rapid, sensitive, and accurate HPLC-DAD method was developed and validated for simultaneous determination of one phenolic glycoside and seven monoterpene glycosides, including 1-O-?-d-(4-hydroxybenzoyl)glucose (1), pyridylpaeoniflorin (2), (8R)-piperitone-4-en-9-O-?-d-glucopyranoside (3), oxypaeoniflorin (4), 6'-O-?-glucopyranosylalbiflorin (5), albiflorin (6), ?-gentiobiosylpaeoniflorin (7), and paeoniflorin (8), in 44 batches of peony seeds from nine Paeonia species collected from different areas. Using the optimised method, separations were conducted with a YMC-pack ODS-A column with water/formic acid and methanol as the mobile phase. All eight analytes demonstrated good linearity (r(2)>0.9993). The recoveries, measured at three concentration levels, varied from 98.20% to 103.81%. Six compounds including 1 and 4-8 occur ubiquitously in all the seeds of nine Paeonia species, and compounds 2 and 3 showed undetectable levels or very low content in several samples. The seed samples were classified into several groups, which coincide with the taxonomy of Paeonia at the section level. Peony seed might be a useful resource in developing new herbal or food products. PMID:23497864

He, Chunnian; Peng, Yong; Xiao, Wei; Liu, Haibo; Xiao, Pei-Gen

2013-06-15

16

Differential effects of quercetin glycosides on GABAC receptor channel activity.  

PubMed

Quercetin, a representative flavonoid, is a compound of low molecular weight found in various colored plants and vegetables. Quercetin shows a wide range of neuropharmacological activities. In fact, quercetin naturally exists as monomer-(quercetin-3-O-rhamnoside) (Rham1), dimer-(Rutin), or trimer-glycosides [quercetin-3-(2(G)-rhamnosylrutinoside)] (Rham2) at carbon-3 in fruits and vegetables. The carbohydrate components are removed after ingestion into gastrointestinal systems. The role of the glycosides attached to quercetin in the regulation of ?-aminobutyric acid class C (GABAC) receptor channel activity has not been determined. In the present study, we examined the effects of quercetin glycosides on GABAC receptor channel activity by expressing human GABAC alone in Xenopus oocytes using a two-electrode voltage clamp technique and also compared the effects of quercetin glycosides with quercetin. We found that GABA-induced inward current (I GABA ) was inhibited by quercetin or quercetin glycosides. The inhibitory effects of quercetin and its glycosides on I GABA were concentration-dependent and reversible in the order of Rutin ? quercetin ? Rham 1 > Rham 2. The inhibitory effects of quercetin and its glycosides on I GABA were noncompetitive and membrane voltage-insensitive. These results indicate that quercetin and its glycosides regulate GABAC receptor channel activity through interaction with a different site from that of GABA, and that the number of carbohydrate attached to quercetin might play an important role in the regulation of GABAC receptor channel activity. PMID:24895146

Kim, Hyeon-Joong; Lee, Byung-Hwan; Choi, Sun-Hye; Jung, Seok-Won; Kim, Hyun-Sook; Lee, Joon-Hee; Hwang, Sung-Hee; Pyo, Mi-Kyung; Kim, Hyoung-Chun; Nah, Seung-Yeol

2015-01-01

17

Herbaceous Peony (Paeonia lactiflora Pall.) as an Alternative Source of Oleanolic and Ursolic Acids  

PubMed Central

Oleanolic acid (OA) and ursolic acid (UA) have been proven to possess many biological activities, and much attention is focused on the search for plants which are rich in OA and UA. In this report, the OA and UA accumulation characteristics were investigated in 47 cultivars of Chinese herbaceous peony (Paeonia lactiflora Pall.) and were followed in three cultivars over different developmental stages as measured by high performance liquid chromatography (HPLC). OA and UA levels in leaves and stems demonstrated an overall upward trend from May 1 to September 15 except for UA in the leaves of “Hong Feng”. The maximum values of OA and UA in leaves of “Yangfei Chu Yu”, “Fen Zhu Pan” and “Hong Feng” were 852.98, 575.60, 290.48 ?g/g FW and 924.94, 827.36, 432.67 ?g/g FW, respectively. The maximum values of OA and UA in stems of “Yangfei Chu Yu”, “Fen Zhu Pan” and “Hong Feng” were 359.28, 90.49, 43.90 ?g/g FW and 326.86, 82.25, 56.63 ?g/g FW, respectively. OA and UA contents in leaves of 47 different herbaceous peony cultivars ranged from 66.73–618.12 and 36.23–665.14 ?g/g FW, respectively, with average values of 171.62 and 227.57 ?g/g FW, respectively. The results suggested that the aboveground parts of herbaceous peony may be used as an alternative source of OA and UA for medicinal purposes in addition to its ornamental purposes. PMID:21340006

Zhou, Chunhua; Zhang, Ying; Sheng, Yanle; Zhao, Daqiu; Lv, Sansan; Hu, Yue; Tao, Jun

2011-01-01

18

Variants of glycoside hydrolases  

DOEpatents

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

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

2011-04-26

19

Variants of glycoside hydrolases  

DOEpatents

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

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

2013-02-26

20

Quinoid glycosides from Forsythia suspensa.  

PubMed

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

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

2014-08-01

21

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

22

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

23

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

24

Glycosyl fluorides in glycosidations.  

PubMed

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

Toshima, K

2000-07-10

25

Bioinspired peony-like beta-Ni(OH)2 nanostructures with enhanced electrochemical activity and superhydrophobicity.  

PubMed

Constructing complex nanostructures has become increasingly important in the development of hydrogen storage, self-cleaning materials, and the formation of chiral branched nanowires. Several approaches have been developed to generate complex nanostructures, which have led to novel applications. Combining biology and nanotechnology through the utilization of biomolecules to chemically template the growth of complex nanostructures during synthesis has aroused great interest. Herein, we use a biomolecule-assisted hydrothermal method to synthesize beta-phase Ni(OH)(2) peony-like complex nanostructures with second-order structure nanoplate structure. The novel beta-Ni(OH)(2) nanostructures exhibit high-power Ni/MH battery performance, close to the theoretical capacity of Ni(OH)(2), as well as controlled wetting behavior. We demonstrate that this bioinspired route to generate a complex nanostructure has applications in environmental protection and green secondary cells. This approach opens up opportunities for the synthesis and potential applications of new kinds of nanostructures. PMID:19998313

Cao, Huaqiang; Zheng, He; Liu, Kaiyu; Warner, Jamie H

2010-02-01

26

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

27

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

28

The phylogeographic structure and conservation genetics of the endangered tree peony, Paeonia rockii (Paeoniaceae), inferred from chloroplast gene sequences  

Microsoft Academic Search

The endangered species Paeonia rockii is the most important ancestral species of the cultivated tree peonies. These well-known ornamental plants are termed the\\u000a ‘King of Flowers’ in China. In this study, we investigated the genetic diversity and phylogeographic structure of 335 wild\\u000a samples from 20 populations throughout the entire distributional range of the species based on three chloroplast DNA sequences

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

29

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. PMID:25405227

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

2014-01-01

30

Enzymatic glycosidations in dry media on mineral supports  

Microsoft Academic Search

Preparation of 4-hydroxybutyl-?-D-glucoside was achieved by reversed hydrolysis from glucose using almond-?-glucosidase impregnated on mineral supports, while 4-hydroxybutyl-?-D-glucoside was obtained from glucose or by one-pot starch hydrolysis followed by glucosidation catalysed by ?-amylase (amyloglucosidase) from Rhizopus mold on celites. The influence of the support nature and of water activity were investigated in order to shift the equilibrium towards glycosidation.

Mirjana Gelo-Pujic; Eryka Guibé-Jampel; André Loupy

1997-01-01

31

Propargyl glycosides as stable glycosyl donors: anomeric activation and glycoside syntheses.  

PubMed

The advantages of stable glycosyl donors for saccharide coupling are many, and we describe herein the utility of propargyl glycosides for anomeric activation and glycoside synthesis exploiting the alkynophilicity of AuCl3. Various aglycones were reacted with propargyl glycosides, resulting in the formation of an alpha,beta-mixture of glycosides and disaccharides in good yields. PMID:16866502

Hotha, Srinivas; Kashyap, Sudhir

2006-08-01

32

Iridoid and phenolic glycosides from Wulfenia carinthiaca.  

PubMed

Two new phenylpropanoid glycosides (2'-O-acetylplantamajoside and 2'-O, 6"-O-diacetylplantamajoside), a new iridoid glycoside (10-O-(cinnamoyl)-6'-O-(desacetylalpinosidyl)-catalpol), the two known iridoid glycosides globularin and isoscrophularioside, and the known phenylpropanoid glycoside platamajoside were isolated from the methanolic extract of the underground parts of Wulfenia carinthiaca. Structure elucidations were based on high-resolution mass spectrometry and extensive 1-D and 2-D NMR spectroscopy. PMID:12562078

Arnold, Ulrike W; Zidorn, Christian; Ellmerer, Ernst P; Stuppner, Hermann

2002-01-01

33

Effect of root length on epicotyl dormancy release in seeds of Paeonia ludlowii, Tibetan peony  

PubMed Central

Background and Aims Epicotyl dormancy break in seeds that have deep simple epicotyl morphophysiological dormancy (MPD) requires radicle emergence and even a certain root length in some species. However, the mechanisms by which root length affects epicotyl dormancy break are not clear at present. This study aims to explore the relationship between root length and epicotyl dormancy release in radicle-emerged seeds of Tibetan peony, Paeonia ludlowii, with discussion of the possible mechanisms. Methods Radicle-emerged seeds (radicle length 1·5, 3·0, 4·5 and 6·0 cm) were incubated at 5, 10 and 15 °C. During the stratification, some seeds were transferred to 15 °C and monitored for epicotyl–plumule growth. Hormone content was determined by ELISA, and the role of hormones in epicotyl dormancy release was tested by exogenous hormone and embryo culture. Key Results Cold stratification did not break the epicotyl dormancy until the root length was ?6 cm. The indole-3-actic acid (IAA) and GA3 contents of seeds having 6 cm roots were significantly higher than those of seeds with other root lengths, but the abscisic acid (ABA) content was lowest among radicle-emerged seeds. GA3 (400 mg L?1) could break epicotyl dormancy of all radicle-emerged seeds, while IAA (200 mg L?1) had little or no effect. When grown on MS medium, radicles of naked embryos grew and cotyledons turned green, but epicotyls did not elongate. Naked embryos developed into seedlings on a mixed medium of MS + 100 mg L?1 GA3. Conclusions A root length of ?6·0 cm is necessary for epicotyl dormancy release by cold stratification. The underlying reason for root length affecting epicotyl dormancy release is a difference in the GA3/ABA ratio in the epicotyl within radicle-emerged seeds, which is mainly as a result of a difference in ABA accumulation before cold stratification. PMID:24284815

Hao, Hai-ping; He, Zhi; Li, Hui; Shi, Lei; Tang, Yu-Dan

2014-01-01

34

Glycosides of Patrinia sibirica . I  

Microsoft Academic Search

Conclusions  Three glycosides, named sibirosides A, B, and C, have been detected in the roots ofPatrinia sibirica (L.) Juss. All three are derivatives of hederagenin. Sibirosides A and C were isolated in the pure state and the complete\\u000a structure of the former was established. It was shown that sibiroside C is a hexaoside of hederagenin, with carbohydrate chains\\u000a consisting of two

V. G. Bukharov; V. V. Karlin

1970-01-01

35

Megastigmane glycosides from Salvia nemorosa  

Microsoft Academic Search

From the aerial parts of Salvia nemorosa, three new megastigmane glycosides, salvionosides A-C, were isolated, along with the known compounds, (6S,9R)- and (6S,9S)-roseosides, (6R,9R)- and (6R,9S)-3-oxo-?-ionol glucosides and blumeol C glucoside. The structures of the new compounds were elucidated on the basis of spectral and chemical evidence.

Yoshio Takeda; Hongjie Zhang; Takashi Matsumoto; Hideaki Otsuka; Yasushi Oosio; Gisho Honda; Mamoru Tabata; Tetsuro Fujita; Handong Sun; Ekrem Sezik; Erdem Yesilada

1997-01-01

36

Megastigmane glycosides from Salvia nemorosa.  

PubMed

From the aerial parts of Salvia nemorosa, three new megastigmane glycosides, salvionosides A-C, were isolated, along with the known compounds, (6S,9R)- and (6S,9R)-roseosides, (6R,9R)- and (6R,9S)-3-oxo-alpha-ionol glucosides and blumeol C glucoside. The structures of the new compounds were elucidated on the basis of spectral and chemical evidence. PMID:8983215

Takeda, Y; Zhang, H; Matsumoto, T; Otsuka, H; Oosio, Y; Honda, G; Tabata, M; Fujita, T; Sun, H; Sezik, E; Yesilada, E

1997-01-01

37

Steroidal glycosides from Ruscus ponticus.  

PubMed

A comparative metabolite profiling of the underground parts and leaves of Ruscus ponticus was obtained by an HPLC-ESIMS(n) method, based on high-performance liquid chromatography coupled to electrospray positive ionization multistage ion trap mass spectrometry. The careful study of HPLC-ESIMS(n) fragmentation pattern of each chromatographic peak, in particular the identification of diagnostic product ions, allowed us to get a rapid screening of saponins belonging to different classes, such as dehydrated/or not furostanol, spirostanol and pregnane glycosides, and to promptly highlight similarities and differences between the two plant parts. This approach, followed by isolation and structure elucidation by 1D- and 2D-NMR experiments, led to the identification of eleven saponins from the underground parts, of which two dehydrated furostanol glycosides and one new vespertilin derivative, and nine saponins from R. ponticus leaves, never reported previously. The achieved results highlighted a clean prevalence of furostanol glycoside derivatives in R. ponticus leaves rather in the underground parts of the plant, which showed a wider structure variety. In particular, the occurrence of dehydrated furostanol derivatives, for the first time isolated from a Ruscus species, is an unusual finding which makes unique the saponins profile of R. ponticus. PMID:21354581

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

2011-05-01

38

Systematic qualitative and quantitative assessment of fatty acids in the seeds of 60 tree peony (Paeonia section Moutan DC.) cultivars by GC-MS.  

PubMed

Seeds from Paeonia ostii and Paeoniarockii have been recently identified as novel resources of ?-linolenic acid (ALA) in China. To assess whether tree peony cultivars can be used as oil resource, fatty acids (FAs) in 60 cultivars were monitored and evaluated in this study. The results indicated that the composition and content of FAs varied dramatically among different cultivars, in which ALA, linoleic acid, oleic acid, palmitic acid, and stearic acid were the dominant. The 60 cultivars were classified into six clusters by hierarchical cluster analysis, and they were quite distinct from each other. Finally, six cultivars with high yield and high quality were screened out, comprising of 'Liuliguanzhu', 'Hongguanyupei', 'LSS-2', 'LSS-1', 'Jingshenhuanfa' and 'LSS-11'. These cultivars were appropriately applied in practical oil production. Overall, tree peony oil with abundant unsaturated fatty acids especially ALA was proved to be a top-grade source for edible oil and nutritional supplements. PMID:25466004

Li, Shan-Shan; Yuan, Ru-Yu; Chen, Li-Guang; Wang, Liang-Sheng; Hao, Xiang-Hong; Wang, Li-Jin; Zheng, Xu-Chen; Du, Hui

2015-04-15

39

Flavanone glycosides from Miconia trailii.  

PubMed

Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia trailii yielded two new flavanone glycosides, matteucinol 7-O-alpha-l-arabinopyranosyl(1-->6)-beta-d-glucopyranoside (miconioside A, 1) and farrerol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (miconioside B, 2), along with the known compounds matteucinol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (3), matteucinol (4), 2alpha,3beta,19alpha-trihydroxyolean-12-ene-24,28-dioic acid (bartogenic acid, 5), 2alpha,3beta,23-trihydroxyolean-12-ene-28-oic acid (arjunolic acid, 6), 2alpha,3alpha,19alpha, 23-tetrahydroxyurs-12-ene-28-oic acid (myrianthic acid, 7), and stigmast-4-ene-3,6-dione (8). The structures of 1-8 were elucidated by spectroscopic methods, including 2D NMR. PMID:12542342

Zhang, Zhizhen; ElSohly, Hala N; Li, Xing-Cong; Khan, Shabana I; Broedel, Sheldon E; Raulli, Robert E; Cihlar, Ronald L; Walker, Larry A

2003-01-01

40

New kaurene diterpenoid glycosides from fenugreek seeds.  

PubMed

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

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

2013-01-01

41

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

Microsoft Academic Search

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

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

2002-01-01

42

A new phenolic glycoside from prunella vulgaris.  

PubMed

A new phenolic glycoside was isolated from the spikes of Prunella vulgaris. Its structure was elucidated as gentisic acid 5-O-beta-D-(6'-salicylyl)-glucopyranoside by spectroscopic evidence and chemical analysis. PMID:21800544

Gu, Xiao-jie; Li, You-bin; Mu, Jun; Zhang, Yi

2011-05-01

43

Stereoselective Synthesis of ?-manno-Glycosides  

NASA Astrophysics Data System (ADS)

Among the various types of O-glycosides with biological relevance, the ?-glycoside of D-mannose (?-manno-glycoside) has been considered as one of the most challenging targets from a synthetic point of view. The majority of synthetic approaches to ?-manno-glycoside can be put into two categories (the direct glycosylation and the glycosylation-inversion approaches). Additionally, a variety of intriguing approaches have been investigated with substantial success (alkylative glycosylation of 1,2-stannylene acetal, reductive manipulation of orthoester, intramolecular aglycon delivery, and enzymatic glycosylation). In this chapter, progress in the conceptually demanding ?-mannosylation technology will be discussed, including current state of the art, with particular focus upon applications related to the synthesis of glycoprotein-related oligosaccharides.

Ishiwata, Akihiro; Ito, Yukishige

44

Cycloartane triterpene glycosides from Astragalus trigonus  

Microsoft Academic Search

Three new cycloartane glycosides, trigonoside I, II and III, and the known astragalosides I and II were isolated from the roots of Astragalus trigonus. The structures of the new glycosides were totally elucidated by high field (600 MHz) NMR analyses as cycloastragenol-6-O-?-xylopyranoside, cycloastragenol-3-O-[?-l-arabinopyranosyl(1 ? 2)-?-d-xylopyranosyl]-6-O-?- d-xylopyranoside and cycloastragenol-3-O-[?-l-arabinopyranosyl(1 ? 2)-?-d-(3-O-acetyl)-xylopyranosyl]-6-O-?-d-xylopyranoside.

Pierluigi Gariboldi; Francesca Pelizzoni; Marco Tatò; Luisella Verotta; Nadia El-Sebakhy; Aya M. Asaad; Rokia M. Abdallah; Soad M. Toaima

1995-01-01

45

Cycloartane glycosides from Sutherlandia frutescens.  

PubMed

Four new cycloartane glycosides, sutherlandiosides A-D (1-4), were isolated from the South African folk medicine Sutherlandia frutescens and their structures established by spectroscopic methods and X-ray crystallography as 1 S,3 R,24S,25-tetrahydroxy-7S,10S-epoxy-9,10- seco-9,19-cyclolanost-9(11)-ene 25-O-beta-D-glucopyranoside (1), 3R,7S,24S,25-tetrahydroxycycloartan-1-one 25-O-beta-D-glucopyranoside (2), 3R,24S,25-trihydroxycycloartane-1,11-dione 25-O-beta-D-glucopyranoside (3), and 7S,24S,25-trihydroxycycloart-2-en-1-one 25-O-beta-D-glucoyranoside (4). Compound 1 represents the first secocycloartane skeleton possessing a 7,10-oxygen bridge. Compounds 2- 4 are also the first examples of naturally occurring cycloartanes with a C-1 ketone functionality. Biosynthetic considerations and chemical evidence suggest that the presence of the C-1 ketone in 2 may facilitate the ring opening of the strained cyclopropane system. PMID:18808182

Fu, Xiang; Li, Xing-Cong; Smillie, Troy J; Carvalho, Paulo; Mabusela, Wilfred; Syce, James; Johnson, Quinton; Folk, William; Avery, Mitchell A; Khan, Ikhlas A

2008-10-01

46

Cycloartane Glycosides from Sutherlandia frutescens  

PubMed Central

Four new cycloartane glycosides, sutherlandiosides A–D (1–4), were isolated from the South African folk medicine Sutherlandia frutescens and their structures established by spectroscopic methods and X-ray crystallography as 1S,3R,24S,25-tetrahydroxy-7S,10S-epoxy-9,10-seco-9,19-cyclolanost-9(11)-ene 25-O-?-d-glucopyranoside (1), 3R,7S,24S,25-tetrahydroxycycloartan-1-one 25-O-?-d-glucopyranoside (2), 3R,24S,25-trihydroxycycloartane-1,11-dione 25-O-?-d-glucopyranoside (3), and 7S,24S,25-trihydroxycycloart-2-en-1-one 25-O-?-d-glucoyranoside (4). Compound 1 represents the first secocycloartane skeleton possessing a 7,10-oxygen bridge. Compounds 2–4 are also the first examples of naturally occurring cycloartanes with a C-1 ketone functionality. Biosynthetic considerations and chemical evidence suggest that the presence of the C-1 ketone in 2 may facilitate the ring opening of the strained cyclopropane system. PMID:18808182

Fu, Xiang; Li, Xing-Cong; Smillie, Troy J.; Carvalho, Paulo; Mabusela, Wilfred; Syce, James; Johnson, Quinton; Folk, William; Avery, Mitchell A.; Khan, Ikhlas A.

2012-01-01

47

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

48

Bioactive phenylpropanoid glycosides from Tabebuia avellanedae.  

PubMed

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

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

2013-01-01

49

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

50

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

51

Steroidal alkaloid glycosides from tomato (Lycopersicon esculentum).  

PubMed

Three new steroidal alkaloid glycosides, lycoperosides F-H (1-3), were isolated from tomato fruits (Lycopersicon sculentum) along with lycoperosides A-D, esculeoside A, and rutin. The structures of these glycosides were characterized as the 3-O-beta-lycotetraosides of 23(R)-23-acetoxy-27-hydroxy-27-O-beta-d-glucopyranosyltomatidine (1), (23S,24R)-23-acetoxy-24-O-beta-d-glucopyranosylsoladulcidine-24-ol (2), and 22-isopimpifolidine (3), by means of their spectroscopic data. Also obtained was the new natural product lycoperodine-1 (4). PMID:15043444

Yahara, Shoji; Uda, Noriko; Yoshio, Eri; Yae, Emiko

2004-03-01

52

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

53

Immunostimulatory effect of a composition isolated from white peony root oral liquid in the treatment of radiation-induced esophagitis  

PubMed Central

The aim of this study was to explore the immune repairing effect of a composition isolated from white peony root oral liquid (cWPROL), a traditional Chinese herbal composition, in the treatment of experimental radiation-induced esophagitis in rats. A total of 128 Wistar rats were randomly divided into eight groups, irradiated with 43 Gy 60Co ?-rays to induce esophagitis and treated by different methods. Flow cytometry, hematological analysis and immune nephelometry were used to detect the absolute numbers and percentages of CD3+, CD4+ and CD8+ T lymphocytes, numbers and classification of leukocytes, and the levels of IgG and complement C3 in the peripheral blood of the rats at each experimental time point. Following irradiation, the total number of leukocytes, absolute numbers and percentages of CD3+, CD4+ and CD8+ T lymphocytes, and levels of IgG and complement C3 in the peripheral blood of the rats were decreased. Furthermore, the total numbers of leukocytes, absolute numbers and percentages of CD3+, CD4+ and CD8+ T lymphocytes, and levels of IgG and complement C3 in the peripheral blood were higher in the administered with cWPROL by intra-esophageal perfusion compared with those in the untreated irradiated groups, but lower in the groups treated with a mixture of lidocaine hydrochloride, dexamethasone sodium phosphate and gentamicin sulfate. This study suggested that cWPROL is able to repair the impaired cellular and humoral immunity of rats with radiation-induced esophagitis. PMID:24137307

WANG, ZHIYU; SHEN, LI; WANG, JUAN; SHAN, BAOEN; ZHANG, LI; LU, FUHE; GUO, XIUJUAN; LI, XING

2013-01-01

54

Effects of Inflorescence Stem Structure and Cell Wall Components on the Mechanical Strength of Inflorescence Stem in Herbaceous Peony  

PubMed Central

Herbaceous peony (Paeonia lactiflora Pall.) is a traditional famous flower, but its poor inflorescence stem quality seriously constrains the development of the cut flower. Mechanical strength is an important characteristic of stems, which not only affects plant lodging, but also plays an important role in stem bend or break. In this paper, the mechanical strength, morphological indices and microstructure of P. lactiflora development inflorescence stems were measured and observed. The results showed that the mechanical strength of inflorescence stems gradually increased, and that the diameter of inflorescence stem was a direct indicator in estimating mechanical strength. Simultaneously, with the development of inflorescence stem, the number of vascular bundles increased, the vascular bundle was arranged more densely, the sclerenchyma cell wall thickened, and the proportion of vascular bundle and pith also increased. On this basis, cellulose and lignin contents were determined, PlCesA3, PlCesA6 and PlCCoAOMT were isolated and their expression patterns were examined including PlPAL. The results showed that cellulose was not strictly correlated with the mechanical strength of inflorescence stem, and lignin had a significant impact on it. In addition, PlCesA3 and PlCesA6 were not key members in cellulose synthesis of P. lactiflora and their functions were also different, but PlPAL and PlCCoAOMT regulated the lignin synthesis of P. lactiflora. These data indicated that PlPAL and PlCCoAOMT could be applied to improve the mechanical strength of P. lactiflora inflorescence stem in genetic engineering. PMID:22606025

Zhao, Daqiu; Han, Chenxia; Tao, Jun; Wang, Jing; Hao, Zhaojun; Geng, Qingping; Du, Bei

2012-01-01

55

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

56

Twisting of glycosidic bonds by hydrolases  

Technology Transfer Automated Retrieval System (TEKTRAN)

Patterns of scissile bond twisting have been found in crystal structures of glycoside hydrolases (GHs) that are complexed with substrates and inhibitors. To estimate the increased potential energy in the substrates that results from this twisting, we have plotted torsion angles for the scissile bond...

57

A new sterol glycoside from Securidaca inappendiculata.  

PubMed

From the roots of Securidaca inappendiculata, one new sterol glycoside securisteroside (1) has been isolated, along with two known sterols, spinasterol (2) and 3-O-beta-D-glucopyranosyl-spinasterol (3). The new sterol was characterized by chemical and spectrometric methods, including EIMS, FABMS and one- and two-dimensional NMR experiments. PMID:16087640

Zhang, Li-Jie; Yang, Xue-Dong; Xu, Li-Zhen; Zou, Zhong-Mei; Yang, Shi-Lin

2005-08-01

58

New xanthone glycosides from Securidaca inappendiculata.  

PubMed

Three new xanthone glycosides, securixanside A (1), securixanside B (2), and securixanside C (3) were isolated from the stems of Securidaca inappendiculata. These compounds were characterized by spectrometric and chemical methods, including FABMS and one- and two-dimensional NMR experiments. PMID:12067160

Yang, Xue-Dong; An, Ning; Xu, Li-Zhen; Yang, Shi-Lin

2002-06-01

59

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

60

Steroidal glycosides from tubers of Ophiopogon japonicus.  

PubMed

A new steroidal saponin, named ophiopogonin E (1), has been isolated from the tubers of Ophiopogon japonicus, along with five known steroidal saponins (2-6). The structure of the new steroidal glycoside was characterized by spectroscopic analysis and acid-catalyzed hydrolysis as pennogenin 3-O-beta-D-xylopyranosyl (1 --> 4)-beta-D-glucopyranoside (1). PMID:16931432

Cheng, Z-H; Wu, T; Yu, B-Y

2006-09-01

61

ALTERNANSUCRASE ACCEPTOR REACTIONS WITH METHYL GLYCOSIDES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alternansucrase (EC 2.4.1.140) is a D-glucansucrase that synthesizes an alternating alpha-(1-3), (1-6)-linked D-glucan from sucrose. It also synthesizes oligosaccharides via D-glucopyranosyl transfer to various acceptor sugars. We have studied the acceptor products arising from methyl glycosides a...

62

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

63

New acylated flavone glycoside from Gnaphalium uliginosum  

Microsoft Academic Search

A new acylated flavone glycoside has been isolated for the first time from the herb marsh cudweed, and for it the structure of 6?-caffeyl-7-ß-D-glucopyranosyloxy-4',5-dihydroxy-3',6'dimethoxyflavone has been established. In addition, the aglycone, identified as 4',5,7-trihydroxy-3',6-dimethoxyflavone has been isolated. The identifications were made on the basis of UV, IR, PMR, and mass spectra, the products of alkaline and acid hydrolyses, and the

M. M. Konopleva; L. P. Smirnova; V. T. Glyzin; V. L. Shelyuto

1979-01-01

64

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

65

?-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

66

Flavonol glycoside production in callus cultures of Epimedium diphyllum.  

PubMed

Callus cultures of Epimedium diphyllum produced a large amount of epimedoside A in addition to a small amount of diphylloside B, ikarisoside C, epimedoside E, diglycosides of des-O-methylanhydroicaritin (8-gamma, gamma-dimethylallylkaempfero). Icariin, epimedins A-C, which are glycosides of anhydroicaritin, were also produced in the callus cultures. Contents of the flavonol glycosides in callus tissue were higher than those of mother plants, but the composition of each flavonol glycoside mixture in the callus cultures was different from that of the original plants. The time-course experiments showed that an inverse relationship existed between cell growth and flavonol glycoside production. Effects of hormonal factors on cell growth and flavonol glycoside production indicated that 2,4-dichlorophenoxyacetic acid was needed for the production of flavonol glycosides. PMID:1368039

Yamamoto, H; Ieda, K; Tsuchiya, S; Yan, K; Tanaka, T; Iinuma, M; Mizuno, M

1992-03-01

67

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

68

Physical mapping of ribosomal RNA genes in peonies (Paeonia, Paeoniaceae) by fluorescent in situ hybridization: implications for phylogeny and concerted evolution.  

PubMed

Physical maps of the 18S-5.8S-26S ribosomal RNA genes (rDNA) were generated by fluorescent in situ hybridization for five diploid Paeonia species, P. delavayi and P. rockii of section Moutan, and P. emodi, P. tenuifolia, and P. veitchii of section Paeonia. Of five pairs of mitotic chromosomes, rDNA loci were mapped near the telomeres of chromosomes 3, 4, and 5 of P. rockii and P. tenuifolia, chromosomes 2, 3, 4, and 5 of P. delavayi, and all five pairs of chromosomes of P. emodi and P. veitchii. Combining this information with the previously obtained rDNA maps of P. brownii and P. californica of section Oneapia, we hypothesized that the most recent common ancestor of extant peony species had three rDNA loci located on chromosomes 3, 4, and 5. Increase in number of rDNA loci occurred later in each of the three sections, and the increase from three to four loci represents a parallel gain of an rDNA locus on chromosome 2 in P. delavayi of section Moutan and P. brownii of section Oneapia. The increase in number of rDNA loci likely resulted from the translocation of rDNA repeats from chromosomes bearing rDNA loci to chromosomes without them; such translocation is probably facilitated by the telomeric location of rDNA loci. For allotetraploid peony species lacking polymorphism in sequences of the internal transcribed spacers (ITS) of rDNA, the rDNAs derived from divergent diploid parents may have been homogenized through concerted evolution among at least six rDNA loci in the allotetraploids. Chromosomal location of rDNA loci has a more substantial impact on the tempo of concerted evolution than the number of loci. PMID:10330077

Zhang, D; Sang, T

1999-05-01

69

Facile access to new C-glycosides and C-glycoside scaffolds incorporating functionalised aromatic moieties.  

PubMed

The tandem ene/intramolecular Sakurai cyclisation (IMSC) reaction has been successfully applied to the synthesis of a range of C-glycosides, with key intermediates offering opportunities for functionalisation of the glycon moiety. To demonstrate the versatility of the approach to access the 2-deoxy-C-glycoside series, we synthesised diastereomerically pure C-glucoside and galactoside derivatives incorporating functionalised aromatic, heteroaromatic and bicyclic aromatic moieties, in addition to the C-homologue of (±)-?-2-deoxy-glucose 6-phosphate. PMID:25486220

Redpath, Philip; Ness, Kerry A; Rousseau, Joanne; Macdonald, Simon J F; Migaud, Marie E

2015-01-30

70

Glycosides from the aerial parts of Patrinia villosa.  

PubMed

An investigation of the Korean medicinal plant Patrinia villosa (THUNB.) JUSS. (Valerianaceae) led to the isolation of two new flavonoid glycosides, patrivilosides 1 (1) and 2 (2), a new iridoid glycoside, patrinovalerosidate (3), and two new saponins, patrinovilosides A (4) and B (5), along with six known compounds including three flavonoid glycosides and three iridoid glycosides. The structures of the new compounds were elucidated based on analysis of their one dimensional (1D)- and 2D-NMR spectra along with their mass spectrometric data and the results of acid hydrolysis. PMID:23800854

Lee, Joo Young; Kim, Ju Sun; Kim, Yeong Shik; Kang, Sam Sik

2013-01-01

71

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

PubMed

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

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

2002-04-01

72

Triterpene glycosides of Patrinia scabiosofolia . I  

Microsoft Academic Search

Conclusions  From the fraction of the feebly polar saponins ofPatrinia scabiosofolia Fisch. et Link oleanolic acid, hederagenin, ?-sitosterol, ?-D-glucopyranoside, and hederagenin 3-?-L-arabopyranoside have\\u000a been isolated.\\u000a \\u000a The polar fraction has yielded two triterpene glycosides. It has been established that one of them is oleanolic acid 3-O-?-D-glucopyranosyl-(1\\u000a ? 4)-?-L-arabinopyranoside, and the other is hederagenin 3-O-?-D-glucopyranosyl-(1 ? 4)-?-L-arabopyranoside.

V. G. Bukharov; V. V. Karlin; T. N. Sidorovich

1970-01-01

73

Triterpene glycosides of Patrinia scabiosofolia ; II  

Microsoft Academic Search

The triterpene glycosides scabiosides D, E, F, and G have been isolated from the roots ofPatrinia scabiosofolia Fisch. et Link. It has been established that scabioside D is O-ß-D-glucopyranosyl-(1 ? 4)-O-a-L-arabopyranosyl-(1 ? 3)-O-oleanoloyl-(28 ? 1)-ß-D-xylopyranose, and scabioside E is O-ß-D-glucopyranosyl-(1 ? 4)-O-a-L-arabopyranosyl-(1 ? 3)-O-oleanoloyl-(28 ? 1)-O-ß-D-xylopyranosyl-(4 ? 1)-a-L-rhamnopyranose.

V. G. Bukharov; V. V. Karlin

1970-01-01

74

Additional minor diterpene glycosides from Stevia rebaudiana.  

PubMed

From the commercial extract of the leaves of Stevia rebaudiana, two additional new diterpenoid glycosides were isolated and their structures were characterized as 13-[(2-O-beta-glucopyranosyl-3-O-beta-D-xylopyranosyl-beta-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid beta-D-glucopyranosyl ester (1) and 13-[(2-O-beta-D-xylopyranosyl-beta-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid beta-D-glucopyranosyl ester (2) on the basis of extensive spectral data (NMR and MS) and chemical studies. PMID:21922898

Chaturvedula, Venkata Sai Prakash; Prakash, Indra

2011-08-01

75

Acylated flavonol glycosides from Eugenia jambolana leaves.  

PubMed

Two acylated flavonol glycosides and 15 known polyphenols have been isolated and identified from the leaves of Eugenca jambolana Lam. The structures of the new compounds were identified as 3-O-(4"-O-acetyl)-alpha-L-rhamnopyranoside of mearnsetin (myricetin 4'-methyl ether) and myricetin 3-O-(4"-O-acetyl-2"-O-galloyl)-alpha-L-rhamnopyranoside. The complete structure elucidation of all isolated metabolites based on chemical and spectroscopic methods of analysis (UV, 1D and 2D NMR) as well as negative ESI-MS with and without CID in-source fragmentation. PMID:11738415

Mahmoud, I I; Marzouk, M S; Moharram, F A; El-Gindi, M R; Hassan, A M

2001-12-01

76

Leishmanicidal cycloartane-type triterpene glycosides from Astragalus oleifolius  

E-print Network

Leishmanicidal cycloartane-type triterpene glycosides from Astragalus oleifolius Meltem O¨ zipek a oleifoliosides A (1) and B (2) were isolated from the lower stem parts of Astragalus oleifo- lius rights reserved. Keywords: Astragalus oleifolius; Leguminosae; Cycloartane-type glycoside; Oleifoliosides

Rüedi, Peter

77

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

78

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

79

Original article Effect of anaerobic fungi on glycoside hydrolase  

E-print Network

Original article Effect of anaerobic fungi on glycoside hydrolase and polysaccharide depolymerase; the cellulolytic bacteria and fungi established popula- tions in the 4 lambs that were similar to those observed in conventional animals. The presence of fungi led to an increase in the activity of most of the glycoside

Paris-Sud XI, Université de

80

Binding of the cardiac glycoside ouabain to intact cells  

PubMed Central

1. Measurements were made of the binding of [3H]ouabain to a variety of cell types. 2. Two components of binding could usually be distinguished: a component that saturated at low glycoside concentrations and a component that increased up to the highest ouabain concentrations examined. 3. Detailed studies with HeLa cells and kidney slices from guinea-pigs showed that the saturable component is probably associated with inhibition of the Na pump. The main evidence for this is (a) at low concentrations of ouabain there is a close correspondence between the concentration of ouabain giving half-maximum binding and the concentration giving half-maximum inhibition of the Na pump; (b) at low glycoside concentrations, binding precedes inhibition of the Na pump; (c) the rate of binding is very sensitive to external K ions, being highest in the absence of K; (d) binding is reversible and the release of ouabain is associated with reactivation of the Na pump, (e) binding is reduced in the absence of Na ions and in the presence of metabolic inhibitors; (f) binding has a Q10 of about 4; and (g) in the presence of Na and ATP, lysed HeLa cells bind a similar amount of ouabain and the binding is sensitive to K ions. 4. The linear component of binding does not seem to involve the Na pump and it may reflect uptake of ouabain into the cell interior. It has a Q10 of 2·5 and is unaffected by K concentrations which have a large effect on the saturable component. 5. Bound ouabain could be removed from HeLa cells by low pH, trichloroacetic acid, urea, high temperatures and 100% ethanol. These agents did not distinguish between the two components of binding. 6. Criteria are developed for estimating the number of Na pumping sites in cells and the data for ouabain-binding to a number of cells is compared with the activity of the (Na + K)-activated ATPase in the same tissues. Although the number of pumping sites varies from less than 1/?2 to 1500/?2 of membrane, the turnover at these sites seems to be fairly constant between 3,500 and 15,000 min-1 at 35° C. PMID:4262774

Baker, P. F.; Willis, J. S.

1972-01-01

81

[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

82

HPLC-PDA method for quinovic acid glycosides assay in Cat's claw (Uncaria tomentosa) associated with UPLC/Q-TOF-MS analysis.  

PubMed

Uncaria tomentosa (Willd.) is a medicinal plant largely used in folk medicine due to its wide range of biological activities, many of which are usually ascribed to the two main classes of secondary metabolites, namely, alkaloids and quinovic acid glycosides. In this work, a reversed phase HPLC-PDA method was developed and validated for the assay of quinovic acid glycosides in crude and dried extracts of Uncaria tomentosa (Cat's claw) bark. The validation comprised tests of specificity, accuracy, linearity, intermediate precision, repeatability and limits of detection and of quantification. Alpha-hederin was used as the external standard. High coefficients of determination with lower R.S.D. were achieved for both external standard and crude extract. The structural characterization of the main quinovic acid glycosides presented in the crude extract was carried out through UPLC/Q-TOF-MS. The identities of the compounds were obtained through the comparison of their fragmentation patterns with those reported in the literature. The analytical method was successfully applied for quantifying quinovic acid glycosides in two different dried extracts from U. tomentosa and in one quinovic acid glycosides purified fraction. PMID:22296654

Pavei, Cabral; Kaiser, Samuel; Verza, Simone Gasparin; Borre, Gustavo Luis; Ortega, George Gonzalez

2012-03-25

83

Neuroprotective polyhydroxypregnane glycosides from Cynanchum otophyllum.  

PubMed

Five new polyhydroxypregnane glycosides, namely cynanotosides A-E (1-5), together with two known analogues, deacetylmetaplexigenin (6) and cynotophylloside H (7), were isolated from the roots of Cynanchum otophyllum. Their structures were established by spectroscopic methods and acid hydrolysis. The neuroprotective effects of compounds 1-7 against glutamate-, hydrogen peroxide-, and homocysteic acid (HCA)-induced cell death were tested by MTT assay in a hippocampal neuronal cell line HT22. Compounds 1, 2, and 7 exhibited protective activity against HCA-induced cell death in a dose-dependent manner ranging from 1 to 30?M, which may explain the Traditional Chinese Medicine (TCM) use of this plant for the treatment of epilepsy. PMID:23831785

Zhao, Zhi-Min; Sun, Zhang-Hua; Chen, Mei-Hui; Liao, Qiong; Tan, Ming; Zhang, Xin-Wen; Zhu, Han-Dong; Pi, Rong-Biao; Yin, Sheng

2013-10-01

84

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

85

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

86

Cytotoxic triterpene glycosides from the sea cucumber Pseudocolochirus violaceus.  

PubMed

A new triterpene glycoside (1) along with the known intercedenside B (2) was isolated from the sea cucumber Pseudocolochirus violaceus. Glycoside 1 was elucidated as 3-O-{6-O-sodiumsulfate-3-O-methyl-beta-D-glucopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-[beta-D-xylopyranosyl(1-->2)]-beta-D-quinovopyranosyl-(1-->2)-4-O-sodiumsulfate-beta-D-xylopyranosyl}-16beta-acetoxy-holosta-7, 24-diene-3beta-ol on the basis of extensive spectral studies and chemical evidence. Both the glycosides exhibited significant cytotoxicity against cancer cell lines MKN-45 and HCT-116. PMID:17493770

Zhang, Shu-Yu; Tang, Hai-Feng; Yi, Yang-Hua

2007-06-01

87

Cytotoxic triterpene glycosides from the sea cucumber Pseudocolochirus violaceus  

Microsoft Academic Search

A new triterpene glycoside (1) along with the known intercedenside B (2) was isolated from the sea cucumber Pseudocolochirus violaceus. Glycoside 1 was elucidated as 3-O-{6-O-sodiumsulfate-3-O-methyl-?-d-glucopyranosyl-(1?3)-?-d-xylopyranosyl-(1?4)-[?-d-xylopyranosyl(1?2)]-?-d-quinovopyranosyl-(1?2)-4-O-sodiumsulfate-?-d-xylopyranosyl}-16?-acetoxy-holosta-7, 24-diene-3?-ol on the basis of extensive spectral studies and chemical evidence. Both the glycosides exhibited significant cytotoxicity against cancer cell lines MKN-45 and HCT-116.

Shu-Yu Zhang; Hai-Feng Tang; Yang-Hua Yi

2007-01-01

88

Documentation of reticulate evolution in peonies (Paeonia) using internal transcribed spacer sequences of nuclear ribosomal DNA: implications for biogeography and concerted evolution.  

PubMed Central

The internal transcribed spacers (ITS) of nuclear ribosomal DNA of 33 species of genus Paeonia (Paeoniaceae) were sequenced. In section Paeonia, different patterns of nucleotide additivity were detected in 14 diploid and tetraploid species at sites that are variable in the other 12 species of the section, suggesting that reticulate evolution has occurred. Phylogenetic relationships of species that do not show additivity, and thus ostensibly were not derived through hybridization, were reconstructed by parsimony analysis. The taxa presumably derived through reticulate evolution were then added to the phylogenetic tree according to additivity from putative parents. The study provides an example of successfully using ITS sequences to reconstruct reticulate evolution in plants and further demonstrates that the sequence data could be highly informative and accurate for detecting hybridization. Maintenance of parental sequences in the species of hybrid origin is likely due to slowing of concerted evolution caused by the long generation time of peonies. The partial and uneven homogenization of parental sequences displayed in nine species of putative hybrid origin may have resulted from gradients of gene conversion. The documented hybridizations may have occurred since the Pleistocene glaciations. The species of hybrid origin and their putative parents are now distantly allopatric. Reconstruction of reticulate evolution with sequence data, therefore, provides gene records for distributional histories of some of the parental species. Images Fig. 1 PMID:7624325

Sang, T; Crawford, D J; Stuessy, T F

1995-01-01

89

New benzophenone and quercetin galloyl glycosides from Psidium guajava L.  

PubMed

New benzophenone and flavonol galloyl glycosides were isolated from an 80% MeOH extract of Psidium guajava L. (Myrtaceae) together with five known quercetin glycosides. The structures of the novel glycosides were elucidated to be 2,4,6-trihydroxybenzophenone 4-O-(6''-O-galloyl)-beta-D: -glucopyranoside (1, guavinoside A), 2,4,6-trihydroxy-3,5-dimethylbenzophenone 4-O-(6''-O-galloyl)-beta-D: -glucopyranoside (2, guavinoside B), and quercetin 3-O-(5''-O-galloyl)-alpha-L: -arabinofuranoside (3, guavinoside C) by NMR, MS, UV, and IR spectroscopies. Isolated phenolic glycosides showed significant inhibitory activities against histamine release from rat peritoneal mast cells, and nitric oxide production from a murine macrophage-like cell line, RAW 264.7. PMID:20354804

Matsuzaki, Keiichi; Ishii, Rie; Kobiyama, Kaori; Kitanaka, Susumu

2010-07-01

90

Iridal glycosides from Iris spuria (Zeal), cultivated in Egypt  

Microsoft Academic Search

Several iridal and isoiridal glycosides (e.g. 6a) were isolated from Iris spuria (Zeal), cultivated in Egypt. The structures of the compounds were elcucidated by NMR and mass spectroscopy, sugar analysis and ozonolysis.

Franz-Josef Marner; Abdel Nasser Badawi Singab; Mohamed Mohamed Al-Azizi; Nasr Ahmed El-Emary; Mathias Schäfer

2002-01-01

91

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

92

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

93

Two new triterpenoidal glycosides from Medicago polymorpha L.  

PubMed

Two new triterpenoid glycosides called medicago-saponins P1 (1) and P2 (2) were isolated together with five known glycosides from the aerial parts of Medicago polymorpha L. (Leguminosae). The structures of 1 and 2 were determined to be 3-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl caulophyllogenin 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside and the desglucoside of 1. PMID:8069980

Kinjo, J; Uemura, H; Nakamura, M; Nohara, T

1994-06-01

94

Fully acetylated carbamate and hypotensive thiocarbamate glycosides from Moringa oleifera.  

PubMed

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. Thiocarbamates showed hypotensive activity. PMID:7766390

Faizi, S; Siddiqui, B S; Saleem, R; Siddiqui, S; Aftab, K; Gilani, A H

1995-03-01

95

Phenylethanoid glycosides from the roots of Phlomis umbrosa.  

PubMed

The phytochemical study of the roots of Phlomis umbrosa Turcz. afforded three new phenylethanoid glycosides, 3'''-acetyl-O-betonyoside D (1), 2''', 3'''-di-acetyl-O- betonyoside D (2), and 3''', 4'''-di-acetyl-O-betonyoside D (3), along with five known phenylethanoid glycosides. Their structures were elucidated on the basis of spectroscopic data. The antitumor activity of the isolated compounds was investigated. PMID:19177241

Liu, Pu; Deng, Rui-Xue; Duan, Hong-Quan; Yin, Wei-Ping; Zhao, Tian-Zeng

2009-01-01

96

Indole Alkaloid Glycosides from the Aerial Parts of Strobilanthes cusia.  

PubMed

Three indole alkaloid glycosides, strobilanthosides A-C (1-3), two known indole alkaloid glucosides (4 and 5), and five phenylethanoid glycosides (8-10) were isolated from the aerial parts of Strobilanthes cusia. The structures of the new compounds were elucidated by spectrometric analysis, and the absolute configurations of 1 and 2 were established by ECD spectrocsopy. N'-?-d-Glucopyranosylindirubin (5) showed weak antibacterial activity (MIC 62.5-125 ?M) against Staphylococcus aureus. PMID:25427242

Gu, Wei; Zhang, Yu; Hao, Xiao-Jiang; Yang, Fu-Mei; Sun, Qian-Yun; Morris-Natschke, Susan L; Lee, Kuo-Hsiung; Wang, Yue-Hu; Long, Chun-Lin

2014-12-26

97

Stability of steviol glycosides in several food matrices.  

PubMed

As steviol glycosides are now allowed as a food additive in the European market, it is important to assess the stability of these steviol glycosides after they have been added to different food matrices. We analyzed and tested the stability of steviol glycosides in semiskimmed milk, soy drink, fermented milk drink, ice cream, full-fat and skimmed set yogurt, dry biscuits, and jam. The fat was removed by centrifugation from the dairy and soy drink samples. Proteins were precipitated by the addition of acetonitrile and also removed by centrifugation. Samples of jam were extracted with water. Dry biscuits were extracted with ethanol. The resulting samples were concentrated with solid-phase extraction and analyzed by high-performance liquid chromatography on a C18 stationary phase and a gradient of acetonitrile/aqueous 25 mM phosphoric acid. The accuracy was checked using a standard addition on some samples. For assessing the stability of the steviol glycosides, samples were stored in conditions relevant to each food matrix and analyzed periodically. The results indicate that steviol glycosides can be analyzed with good precision and accuracy in these food categories. The recovery was between 96 and 103%. The method was also validated by standard addition, which showed excellent agreement with the external calibration curve. No sign of decomposition of steviol glycosides was found in any of the samples. PMID:23020306

Jooken, Etienne; Amery, Ruis; Struyf, Tom; Duquenne, Barbara; Geuns, Jan; Meesschaert, Boudewijn

2012-10-24

98

Structure and absolute configuration of clerodane diterpene glycosides and a rearranged cadinane sesquiterpene glycoside from the stems of Tinospora sinensis.  

PubMed

Three new clerodane diterpene glycosides, tinosposinensides A-C ( 1- 3), and a new rearranged cadinane sesquiterpene glycoside, tinosinenside ( 4), were isolated from the stems of Tinospora sinensis. The structure including the relative configuration was elucidated on the basis of spectroscopic analysis. The absolute configuration was determined by application of the modified Mosher's method and chemical transformation. The inhibitory activities of the isolated compounds against alpha-glucosidase are also described. PMID:18020421

Li, Wei; Wei, Kun; Fu, Hongwei; Koike, Kazuo

2007-12-01

99

Resin Glycosides from the Morning Glory Family  

NASA Astrophysics Data System (ADS)

Resin glycosides are part of a very extensive family of secondary metabolites known as glycolipids or lipo-oligosaccharides and are constituents of complex resins (glycoresins) (1) unique to the morning glory family, Convolvulaceae (2). These active principles are responsible for the drastic purgative action of all the important Convolvulaceous species used in traditional medicine throughout the world since ancient times. Several commercial purgative crude drugs can be prepared from the roots of different species of Mexican morning glories. Their incorporation as therapeutic agents in Europe is an outstanding example of the assimilation of botanical drugs from the Americas as substitutes for traditional Old World remedies (3). Even though phytochemical investigations on the constituents of these drugs were initiated during the second half of the nineteenth century, the structure of their active ingredients still remains poorly known for some examples of these purgative roots. During the last two decades, the higher resolution capabilities of modern analytical isolation techniques used in conjunction with powerful spectroscopic methods have facilitated the elucidation of the active principles of these relevant herbal products.

Pereda-Miranda, Rogelio; Rosas-Ramírez, Daniel; Castañeda-Gómez, Jhon

100

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

101

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

102

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

103

Structures of Some Novel ?-Glucosyl Diterpene Glycosides from the Glycosylation of Steviol Glycosides.  

PubMed

Four new minor diterpene glycosides with a rare ?-glucosyl linkage were isolated from a cyclodextrin glycosyltransferase glucosylated stevia extract containing more than 98% steviol glycosides. The new compounds were identified as 13-[(2-O-?-D-glucopyranosyl-3-O-(4-O-?-D-glucopyranosyl)-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(4-O-?-D-glucopyranosyl-?-D-glucopyranosyl) ester] (1), 13-[(2-O-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(4-O-(4-O-(4-O-?-D-glucopyranosyl)-?-D-glucopyranosyl)-?-D-glucopyranosyl)-?-D-glucopyranosyl ester] (2), 13-[(2-O-?-D-glucopyranosyl-3-O-(4-O-(4-O-(4-O-?-D-glucopyranosyl)-?-D-glucopyranosyl)-?-D-glucopyranosyl)-?-D-glucopyranosyl-?-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid ?-D-glucopyranosyl ester (3), and 13-[(2-O-?-D-glucopyranosyl-3-O-(4-O-(4-O-(4-O-?-D-glucopyranosyl)-?-D-glucopyranosyl)-?-D-glucopyranosyl)-?-D-glucopyranosyl- ?-D-glucopyranosyl)oxy] ent-kaur-16-en-19-oic acid-[(4-O-?-D-glucopyranosyl-?-D-glucopyranosyl) ester] (4) on the basis of extensive NMR and mass spectral (MS) data as well as hydrolysis studies. PMID:25486243

Prakash, Indra; Chaturvedula, Venkata Sai Prakash

2014-01-01

104

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

105

Five years patenting time frame concerning enzymatic preparation of glycosides.  

PubMed

Carbohydrates are important molecules in various technological fields. The regio- and stereoselective synthesis of oligosaccharides for food and pharmaceutical molecular design and the selective glycosylation of peptides, proteins and drugs, as well as the selective hydrolysis of natural abundant saccharidic materials affording low molecular weight high value- added products, can be all considered significant aspects. Advance in the chemical synthesis of glycosidic bond represents one of the most successful topic in organic synthetic chemistry in the last half century for the intrinsic difficulties chemists have to face dealing with carbohydrates: yields and selectivity. Biocatalytic strategies selected for high-yield and stereospecific construction of glycosidic bonds are based principally on the action of two classes of enzymes, namely glycoside hydrolases (endo- and exo-glycosidases) and glycosyltransferases although only enzymes of the second class are devoted to synthetic action in nature. Reviewing patents on the preparation of glycosides is hard to manage, here a five years time frame for this review is set, considering it a suitable compromise in terms of amount of innovation and numbers of patents to analyze. Interest of researchers for the natural sources of biocatalysts, with particular emphasis on modified enzymes and lists of the most innovative patents in cosmetic, fine chemicals and food fields will be commented. Biomolecular asset of selected patents related to glycosides will be expressly considered. Large number of enzymes will be required in future in order to realize more sustainable new enzymatic processes to answer human needs. PMID:20201801

Trincone, Antonio

2010-01-01

106

ISOFLAVONE CONJUGATES AND MINOR GLYCOSIDES EXTRACTED FROM PEANUT HEARTS USING HPLC-MS  

Technology Transfer Automated Retrieval System (TEKTRAN)

High performance liquid chromatography and electrospray mass spectrometry (ESI) was used to characterize isoflavone glycosidic conjugates and minor glycosides extracted from peanut meal. The selected extraction method combined the removal of isoflavones and their conjugates with an alcoholic solvent...

107

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

108

Anticancer diarylheptanoid glycosides from the inner bark of Betula papyrifera.  

PubMed

Phytochemical investigations of the MeOH extract of Betula papyrifera inner bark led to the isolation of ten phenolic compounds of the following types: diarylheptanoid glycosides (1-4), a diarylheptanoid (5), a lignan (6), flavonoids (7-8) and chavicol glycosides (9-10). Among them, the diarylheptanoid glycoside, (S)-1,7-bis-(4-hydroxyphenyl)-heptan-3-one-5-O-alpha-L-arabinofuranosyl-(1-->6)-beta-D-glucopyranoside, papyriferoside A (1), was isolated and its structure was determined on the basis of 1D and 2D NMR, HPLC-MS, as well as high resolution mass spectroscopic data. Platyphylloside (4) exerted the strongest cytotoxic activity of all isolated compounds with IC(50) values ranging from 10.3 to 13.8 microM. PMID:17599372

Mshvildadze, Vakhtang; Legault, Jean; Lavoie, Serge; Gauthier, Charles; Pichette, André

2007-10-01

109

Selective hydrolysis of flavonoid glycosides by Curvularia lunata.  

PubMed

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

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

2013-11-01

110

Cytotoxic sulfated triterpene glycosides from the sea cucumber Pseudocolochirus violaceus.  

PubMed

Bioassay-guided fractionation of the active BuOH extract of the sea cucumber Pseudocolochirus violaceus resulted in the isolation of three new sulfated triterpene glycosides, i.e., violaceusides I, II, and III (1-3, resp.), as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Their structures were elucidated by spectroscopic methods including 2D-NMR and MS experiments, as well as chemical evidence. Compounds 1-3 exhibit the same structural features, i.e., the presence of a 16-oxo group in the holostane-type triterpene aglycone with the C(7)=C(8) bond, but differ in the side chains and the tetrasaccharide moieties. Compound 1 possesses one sulfate group, while 2 and 3 are disulfated glycosides. All the glycosides showed significant in vitro cytotoxicities against human gastric cancer MKN-45 and human colon cancer HCT-116 cells. PMID:17193313

Zhang, Shu-Yu; Yi, Yang-Hua; Tang, Hai-Feng

2006-07-01

111

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

PubMed

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

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

2013-01-01

112

Cytotoxic cardenolide glycosides from the seeds of Antiaris toxicaria.  

PubMed

Bioassay-guided fractionation of the ethanolic extract from the seeds of Antiaris toxicaria led to the isolation of three new cardiac glycosides named toxicarioside J, toxicarioside K, and toxicarioside L, together with a known glucostrophalloside. The structures of the new compounds were elucidated by spectroscopic methods including HRESIMS, UV, IR, and 1D, 2D NMR techniques. The cytotoxic activities of these cardiac glycosides against human gastric (SGC-7901) and human hepatoma (SMMC-7721) cell lines were evaluated, and all of them exhibited significant cytotoxicity. PMID:21509716

Dong, Wen-Hua; Mei, Wen-Li; Zhao, You-Xing; Zeng, Yan-Bo; Zuo, Wen-Jian; Wang, Hui; Li, Xiao-Na; Dai, Hao-Fu

2011-10-01

113

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

114

New anthraquinone glycosides from the roots of Morinda citrifolia  

Microsoft Academic Search

Six new anthraquinone glycosides: digiferruginol-1-methylether-11-O-?-gentiobioside (1); digiferruginol-11-O-?-primeveroside (2); damnacanthol-11-O-?-primeveroside (3); 1-methoxy-2-primeverosyloxymethyl-anthraquinone-3-olate (4); 1-hydroxy-2-primeverosyloxymethyl-anthraquinone-3-olate (5); and 1-hydroxy-5,6-dimethoxy-2-methyl-7-primeverosyloxyanthraquinone (6) were isolated from Morinda citrifolia (Rubiaceae) roots together with four known anthraquinone glycosides. The structures of the new compounds were established using spectral methods. For five of the new compounds, the sugar is attached via the hydroxymethyl group of the anthraquinone C-2 carbon.

Kohei Kamiya; Wakako Hamabe; Shogo Tokuyama; Toshiko Satake

2009-01-01

115

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

Microsoft Academic Search

A sensitive and specific liquid chromatography tandem mass spectrometry (HPLC–ESI+-MS\\/MS) procedure was developed and validated for the identification and quantification of thevetin B and further cardiac glycosides in human serum. The seeds of Yellow Oleander (Thevetia peruviana) contain cardiac glycosides that can cause serious intoxication. A mixture of six thevetia glycosides was extracted from these seeds and characterized. Thevetin B,

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

116

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

Microsoft Academic Search

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

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

2010-01-01

117

Reverse Osmosis  

NSDL National Science Digital Library

Reverse Osmosis: In reverse osmosis, the idea is to use the membrane to act like an extremely fine filter to create drinkable water from salty (or otherwise contaminated) water. A complete explanation is here along with helpful diagrams.

2008-09-22

118

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

119

Glycosides of marine invertebrates. XV. A new triterpene glycoside — Holothurin A 1 — From Caribbean holothurians of the family Holothuriidae  

Microsoft Academic Search

A glycoside, holothurin A1 has been isolated from the polar glyosidic fractions of the holothuriansH. floridana andH. grisea. The complete structure of the glycoside has been established; it is: 3?-[0-(3-0-methyl-?-D-glucopyranosyl)-(1 ? 3)-0-?-D-glucopyranosyl-(1\\u000a ? 4)-0-?-D-quinovopyranosyl-(1 ? 2)-(4-sulfato-?-D-xylopyranosyl)oxy]holosta-9(11)-ene-12?,17?,22?-triol. Details of the IR\\u000a and1H and13C NMR spectra of the compounds obtained are given.

G. K. Oleinikova; T. A. Kuznetsova; N. S. Ivanova; A. I. Kalinovskii; N. V. Rovnykh; G. B. Elyakov

1982-01-01

120

A new dinorclerone diterpenoid glycoside from Tinospora sinensis.  

PubMed

A new dinorclerone diterpenoid glycoside, named 1-deacetyltinosposide A (1), was isolated from the stem of Tinospora sinensis together with 10 known compounds. Their structures were elucidated on the basis of extensive spectroscopic techniques (MS, IR, 1D and 2D NMR experiments). PMID:20013467

Dong, Lang-Ping; Chen, Chang-Xiang; Ni, Wei; Xie, Bai-Bo; Li, Jun-Zhu; Liu, Hai-Yang

2010-01-01

121

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

122

Glycosidation of Methanol with Ribose: An Interdisciplinary Undergraduate Laboratory Experiment  

ERIC Educational Resources Information Center

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

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

2010-01-01

123

Hydrolytical instability of hydroxyanthraquinone glycosides in pressurized liquid extraction.  

PubMed

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

Wianowska, Dorota

2014-05-01

124

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

125

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

126

Computational analysis of the phylogeny and thermodynamics of glycoside hydrolases  

Microsoft Academic Search

My research has focused on using computation by means of phylogenetic analysis and molecular mechanics docking studies to further extend knowledge of glycoside hydrolases (GHs). Phylogenetic analysis was used to crystallize the fundamental differences between specific types of cellulases in GH family 6 (GH6). Cellulase enzymes were then examined for functional divergence in order to determine the cause of substrate

John Blakely Mertz

2008-01-01

127

A New Flavanonol Glycoside from Adansonia digitata Roots.  

PubMed

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

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

1984-02-01

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

A new tomato pregnane glycoside from the overripe fruits.  

PubMed

A new pregnane glycoside has been isolated from the overripe fruits of Cherry tomato (Mini tomato), Lycopersicon esculentum var. cerasiforme (DUNAL) ALEF. The structure was determined to be 3-O-beta-lycotetraosyl 3beta-hydroxy-5alpha-pregn-16-en-20-one on the basis of spectroscopic analysis. The seasonal variation of the tomato saponin is discussed. PMID:15863937

Fujiwara, Yukio; Yoshizaki, Miho; Matsushita, Sayaka; Yahara, Shoji; Yae, Emiko; Ikeda, Tsuyoshi; Ono, Masateru; Nohara, Toshihiro

2005-05-01

130

Two new dammarane-type glycosides from Phlomis umbrosa.  

PubMed

Two new dammarane-type glycosides, phlomisumbroside A (1) and phlomisumbroside B (2), together with 15 known compounds (3-17) were isolated from the leaves of Phlomis umbrosa Turcz. Their structures were established by the spectroscopic methods including 2D NMR techniques. PMID:23972014

Ding, Ming-Ming; Yan, Fu-Lin; Tan, Jing; Bai, Yi-Xiao; Wang, Xiang; Yang, Yan-Xia

2014-01-01

131

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

132

Jalapinoside, a Macrocyclic Bisdesmoside from the Resin Glycosides of Ipomea purga, as a Modulator of Multidrug Resistance in Human Cancer Cells.  

PubMed

The first macrocyclic bisdesmoside resin glycoside, jalapinoside (4), was purified by preparative-scale recycling HPLC from the MeOH-soluble extracts of Ipomoea purga roots, the officinal jalap. Purgic acid C (3), a new glycosidic acid of ipurolic acid, was identified as 3-O-?-d-quinovopyranoside, 11-O-?-d-quinovopyranosyl-(1?2)-O-?-d-glucopyranosyl-(1?3)-O-[?-d-fucopyranosyl-(1?4)]-O-?-l-rhamnopyranosyl-(1?2)-O-?-d-glucopyranosyl-(1?2)-O-?-d-quinovopyranoside (3S,11S)-dihydroxytetradecanoic acid. The acylating residues of this core were acetic, (+)-(2S)-methylbutanoic, and dodecanoic acids. The site of lactonization was defined as C-3 of the second saccharide moiety. Reversal of multidrug resistance by this noncytotoxic compound was evaluated in vinblastine-resistant human breast carcinoma cells. PMID:25536852

Bautista, Elihú; Fragoso-Serrano, Mabel; Pereda-Miranda, Rogelio

2015-01-23

133

Antiviral phenylpropanoid glycosides from the medicinal plant Markhamia lutea.  

PubMed

Three new phenylpropanoid glycosides, named luteoside A (3), luteoside B (4), and luteoside C (5), were isolated together with the known compounds verbascoside (1) and isoverbascoside (2) from the roots of the medicinal plant Markhamia lutea. The structures of the new compounds were determined to be 1-O-(3, 4-dihydroxyphenyl)ethyl beta-D-apiofuranosyl(1-->2)-alpha-l-rhamnopyranosyl(1-->3)-4-O- caffeo yl-6-acetyl-beta-d-glucopyranoside, 1-O-(3,4-dihydroxyphenyl)ethyl beta-d-apiofuranosyl(1-->2)-alpha-l-rhamnopyranosyl(1-->3)-6-O- caffeo yl-beta-d-glucopyranoside, and 1-O-(3,4-dihydroxyphenyl)ethyl beta-D-apiofuranosyl(1-->2)-alpha-l-rhamnopyranosyl(1-->3)-6-O- ferulo yl-beta-d-glucopyranoside, respectively, on the basis of chemical and spectroscopic data. All five phenylpropanoid glycosides exhibited potent in vitro activity against respiratory syncytial virus. PMID:9599250

Kernan, M R; Amarquaye, A; Chen, J L; Chan, J; Sesin, D F; Parkinson, N; Ye, Z; Barrett, M; Bales, C; Stoddart, C A; Sloan, B; Blanc, P; Limbach, C; Mrisho, S; Rozhon, E J

1998-05-01

134

A glycoside of Nicotina tabacum affects mouse dopaminergic behavior.  

PubMed

Climbing in the forced swimming test is considered a dopaminergic-specific behavior. A substance of Nicotina tabacum affecting dopamine neuronal activity was investigated using the mouse behavioral system. The substance was found to be a glycoside with the peripheral sugar chain structures Fuc alpha 1-2Gal, Gal beta 1-4GlcNAc and GalNAc alpha 1-3GalNAc and with basic polymannoses. The glycoside dose-dependently increased behavior via D2 neuronal activity, but not D1 activity. This suggests that smoking can affect human brain function not only via the nicotinic cholinergic neuron, but also via the D2 neuron. PMID:12690705

Masuda, Y; Ohnuma, S; Kawagoe, M; Sugiyama, T

2003-01-01

135

A new antioxidant flavone glycoside from Scutellaria baicalensis Georgi.  

PubMed

A new flavone glycoside, wogonin 7-O-?-D-ethylglucuronide (1), together with a new natural flavone glycoside baicalein 7-O-?-D-ethylglucuronide (2) and four known analogues, wogonoside (3), wogonin (4), oroxylin A 7-O-?-D-methylglucuronide (5) and oroxylin A (6), was isolated from the roots of Scutellaria baicalensis Georgi. The structure elucidation of the new compound was primarily based on HR-ESI-MS, 1D and 2D NMR analyses. Compounds 1 and 3 inhibited FeSO4-Cys-induced liver homogenate lipid peroxidation with IC50 at 18.2 ?M and 24.9 ?M, respectively, and exhibited strong cytoprotective effects against H2O2-induced oxidative damage in human umbilical vein endothelial cells at low concentrations of 10.0 ?M and 3.0 ?M. PMID:24995563

Wang, Meng-Hua; Li, Lin-Zhen; Sun, Jian-Bo; Wu, Fei-Hua; Liang, Jing-Yu

2014-01-01

136

Cytotoxic triterpene glycosides from the roots of Sanguisorba officinalis.  

PubMed

Phytochemical investigation of the ethanol extract of the roots of Sanguisorba officinalis resulted in the isolation of three new triterpene glycosides, 3?-[(?-L-arabinopyranosyl)oxy]-19?,23-dihydroxyolean-12-en-28-oic acid 28-[6-O-acetyl-?-D-glucopyranosyl] ester (1), 2?,3?,19?,23-tetrahydroxyurs-12-en-28-oic acid 28-[6-O-acetyl-?-D-glucopyranosyl] ester (2), and 3?-[(?-L-arabinopyranosyl)oxy]-19?-hydroxyurs-12,20(30)-dien-28-oic acid 28-[6-O-acetyl-?-D-glucopyranosyl] ester (3). All the triterpene glycosides exhibited the significant cytotoxic potential with low IC50 values (IC50 < 5.0 ?M) against six tumor cell lines (MCF-7, HeLa, HepG2, SGC-7901, NCI-H460, and BGC-823). PMID:25193625

Hu, Jiang; Song, Yan; Li, Hui; Yang, Benshou; Mao, Xia; Zhao, Yongmao; Shi, Xiaodong

2014-09-01

137

New antimicrobial pregnane glycosides from the stem of Ecdysanthera rosea.  

PubMed

Phytochemical investigation on the stem of Ecdysanthera rosea led to the isolation of eight new C-21 pregnane glycoside ecdysosides A-H (1-8), together with one known pregnane glycoside ecdysantheroside A (9). Their structures were elucidated based on extensive spectroscopic data (MS, IR, 1D and 2D NMR) analysis, as well as comparison with the reported literature data. Antimicrobial activities of all the compounds were evaluated against bacteria and yeasts. Compounds 1, 9, 3 and 5 exhibited moderate antibacterial activities against respective Enterococcus faecalis and Providensia smartii, with MIC value of 12.5 ?g/mL. Compound 8 showed significant anti-yeast activity against Cryptococcus neoformans with MIC value of 12.5 ?g/mL. PMID:25454459

Song, Chang-Wei; Lunga, Paul-Keilah; Qin, Xu-Jie; Cheng, Gui-Guang; Gu, Jian-Long; Liu, Ya-Ping; Luo, Xiao-Dong

2014-12-01

138

New terpenoid glycosides obtained from Rosmarinus officinalis L. aerial parts.  

PubMed

Five new terpenoid glycosides, named as officinoterpenosides A1 (1), A2 (2), B (3), C (4), and D (5), together with 11 known ones, (1S,4S,5S)-5-exo-hydrocamphor 5-O-?-d-glucopyranoside (6), isorosmanol (7), rosmanol (8), 7-methoxyrosmanol (9), epirosmanol (10), ursolic acid (11), micromeric acid (12), oleanolic acid (13), niga-ichigoside F1 (14), glucosyl tormentate (15), and asteryunnanoside B (16), were obtained from the aerial parts of Rosmarinus officinalis L. Their structures were elucidated by chemical and spectroscopic methods (UV, IR, HRESI-TOF-MS, 1D and 2D NMR). Among the new ones, 1 and 2, 3 and 4 are diterpenoid and triterpenoid glycosides, respectively; and 5 is a normonoterpenoid. For the known ones, 6 was isolated from the Rosmarinus genus first, and 15, 16 were obtained from this species for the first time. PMID:25200369

Zhang, Yi; Adelakun, Tiwalade Adegoke; Qu, Lu; Li, Xiaoxia; Li, Jian; Han, Lifeng; Wang, Tao

2014-12-01

139

The triterpene glycosides of patrinia intermedia roem et schult  

Microsoft Academic Search

Conclusions  1. It has been found that the trisaccharide residues attached to the carboxyl of the aglycone in patrinosides C and D have\\u000a identical structures and configurations, the middle monosaccharide being glucofuranose.\\u000a \\u000a 2. The complete structures of patrinosides C and D have been established and the configurations of their glycosidic centers\\u000a have been determined.

V. G. Bukharov; V. V. Karlin; V. A. Talan

1969-01-01

140

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

141

Two New Phloroglucinol Glycosides from Lysidice rhodostega Hance  

Microsoft Academic Search

Two new phloroglucinol glycosides, lysidiciside A (1) and lysidiciside B (2), were isolated from the roots of Lysidice rhodostega Hance. Their structures were determined as 1-((3-methylbutyryl)phloroglucinol)-? -D- glucopyranoside (1), 1- ((3-methylbutyryl)phloro- glucinol)-? -D-glucopyranosyl-5-O-? -D-glucopyranoside (2) on the basis of chemical and spectral analysis . Lysidice rhodostega Hance is widely distributed in Guangxi, Guangdong, Yunnan and Guizhou province of China. It

Song GAO; Shi Shan YU; De Quan YU

142

Phenylpropanoid glycosides from the leaves of Paulownia coreana.  

PubMed

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

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

2008-02-15

143

Two antigenotoxic chalcone glycosides from Mentha longifolia subsp. longifolia.  

PubMed

Abstract Context: Mentha L. (Labiatae) species (mint) with their flavoring properties have been used in food industries for centuries. Besides they have a great importance in drug development and medicinal applications due to various bioactive compounds of several members of the genus. Objective: The aim of this study was to isolate bioactive compounds with antimutagenic potential by bio-guided fractionation and determine their structures by spectroscopic methods. Materials and methods: The structural elucidation of the isolated compounds was done based on spectroscopic methods, including MALDI-MS, UV, IR, and 2D NMR experiments, and the bio-guided fractionation process was done by using the Ames/Salmonella test system. Henceforth, solely genotoxic and antigenotoxic potential of the new compounds were also confirmed up to 2?µM/plate by using the same test system. Results: Two new chalcone glycosides: (?R)-?,3,2',6'-tetrahydroxy-4-methoxy-4'-O-rutinosyldihydrochalcone and (?R)-?,4,2',6'-tetrahydroxy-4'-O-rutinosyldihydrochalcone, were isolated from Mentha longifolia (L.) Hudson subsp. longifolia, together with known six flavonoid glycosides and one phenolic acid: apigenin-7-O-glucoside, luteolin-7-O-glucoside, apigenin-7-O-rutinoside, luteolin-7-O-rutinoside, apigenin-7-O-glucuronide, luteolin-7-O-glucuronide, rosmarinic acid. According to the antimutagenicity results, both new test compounds significantly inhibited the mutagenic activity of 9-aminoacridine in a dose-dependent manner at the tested concentrations from 0.8 to 2?µM/plate. (?R)-?,4,2',6'-Tetrahydroxy-4'-O-rutinosyldihydrochalcone showed the maximum inhibition rate as 75.94% at 2?µM/plate concentration. Conclusions: This is the first report that two new chalcone glycosides were isolated from Mentha longifolia subsp. longifolia and their antimutagenic potentials by using mutant bacterial tester strains. In conclusion, the two new chalcone glycosides showed a significant antigenotoxic effect on 9-aminoacridine-induced mutagenesis at tested concentrations. PMID:25429992

Guvenalp, Zuhal; Ozbek, Hilal; Karadayi, Mehmet; Gulluce, Medine; Kuruuzum-Uz, Ayse; Salih, Bekir; Demirezer, Omur

2014-11-28

144

Two new monoterpenoid glycosides from Mentha spicata L  

Microsoft Academic Search

Two new monoterpenoid glycosides, spicatoside A and spicatoside B, were isolated from the whole herbs of Mentha spicata L. which have anti-inflammatory and hemostatic activities. Their structures have been determined on the basis of spectral and chemical analysis. They are (+)-5-[1-(g -D-glucopyranosyloxymethyl)ethenyl]-2-methyl-2-cyclohexen-1-one (1), and (m )-5-{[2-( g -D-glucopyranosyloxy)-1-hydroxy-1-methyl]ethyl}-2-methyl-2-cyclohexen-1-one (2).

Jian Zheng; Li-Jun Wu; Lu Zheng; Bin Wu; Ai-Hua Song

2003-01-01

145

Inhibitory effects of Thai plants ?-glycosides on Trichomonas vaginalis  

Microsoft Academic Search

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

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

2008-01-01

146

Antiinflammatory activity of naturally occurring flavone and flavonol glycosides  

Microsoft Academic Search

Our previous report demonstrated that certain flavonoid aglycones such as apigenin (flavone), quercetin, morin (flavonols),\\u000a and biochanin A (isoflavone) showedin vivo antiinflammatory activityvia topical and oral routes of administration. As a continual study, the various flavonoid glycosides have been evaluated in\\u000a mouse ear edema assay using archidonic acid or crotonoil as a inflammagen. Flavonoids were orally administered (2 mg\\/mouse)\\u000a and

Song Jin Lee; Kun Ho Son; Hyeun Wook Chang; Jae Chul Do; Keun Young Jung; Sam Sik Kang; Hyun Pyo Kim

1993-01-01

147

Iridal glycosides from Iris spuria (Zeal), cultivated in Egypt  

Microsoft Academic Search

Fractionation of a methanol extract obtained from rhizomes of I. spuria (Zeal) resulted in the isolation of seven iridalglycosides 5a,b, 6a-c, 7, 8. The structures of the aglycons and the position of the glycosidic bonds were elucidated by spectroscopic analyses. The nature of the sugar moieties was determined as glucose from capillary GC and GC\\/MS analyses after hydrolysis of the

Franz-Josef Marnera; Abdel Nasser Badawi Singab; Mohamed Mohamed Al-Azizi; Nasr Ahmed El-Emary; Mathias Schafer

148

Toxicological evaluation of the isoflavone puerarin and its glycosides  

Microsoft Academic Search

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

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

2009-01-01

149

Ent -kaurane diterpenoids and glycosides: Isolation, properties, and chemical transformations  

Microsoft Academic Search

This review is devoted to ent-kaurane diterpenoids and related glycosides, which represent two naturally occurring groups of compounds with interesting\\u000a structures and properties. Much useful information about the biogenesis and biological activities of these compounds is presented;\\u000a however, the greatest part of the review covers various aspects of the chemical transformations of native ent-kaurane diterpenoids, namely, their reactions via COOH,

E. Kataev; R. N. Khaybullin; R. R. Sharipova; I. Yu. Strobykina

2011-01-01

150

Enzymatic Biosynthesis of Novel Resveratrol Glucoside and Glycoside Derivatives.  

PubMed

A uridine diphosphate glucosyltransferase from Bacillus licheniformis was overexpressed, purified and incubated with nucleotide diphosphate (NDP) d- and l-sugars to produce glucose, galactose, 2-deoxyglucose, viosamine, rhamnose, and fucose sugar-conjugated resveratrol glycosides. A significantly higher (90%) bioconversion of resveratrol was achieved with ?d-glucose as the sugar donor to produce four different glucosides of resveratrol, resveratrol 3-O-?-d-glucoside, resveratrol 4?-O-?-d-glucoside, resveratrol 3,5-O-?-d-diglucoside, and resveratrol 3,5,4?-O-?-d-triglucoside. The conversion rates and number of products formed were found to vary with the other NDP-sugar donors. Resveratrol 3-O-?-d-2-deoxyglucoside, resveratrol 3,5-O-?-d-di-2-deoxyglucoside were found to be produced while using TDP-2-deoxyglucose as donor, however, monoglycosides resveratrol 4?-O-?-d-galactoside, resveratrol 4?-O-?-d-viosaminoside, resveratrol 3-O-?-l-rhamnoside, resveratrol 3-O-?-l-fucoside were produced from respective sugar donors. Altogether ten diverse glycoside derivatives of medicinally important resveratrol were generated; demonstrating the capacity for YjiC to produce structurally diverse resveratrol glycosides. PMID:25239890

Pandey, Ramesh Prasad; Parajuli, Prakash; Shin, Ju Yong; Lee, Jisun; Lee, Seul; Hong, Young-Soo; Park, Yong Il; Kim, Joong Su; Sohng, Jae Kyung

2014-09-19

151

Development and application of a screening assay for glycoside phosphorylases.  

PubMed

Glycoside phosphorylases (GPs) are interesting enzymes for the glycosylation of chemical molecules. They require only a glycosyl phosphate as sugar donor and an acceptor molecule with a free hydroxyl group. Their narrow substrate specificity, however, limits the application of GPs for general glycoside synthesis. Although an enzyme's substrate specificity can be altered and broadened by protein engineering and directed evolution, this requires a suitable screening assay. Such a screening assay has not yet been described for GPs. Here we report a screening procedure for GPs based on the measurement of released inorganic phosphate in the direction of glycoside synthesis. It appeared necessary to inhibit endogenous phosphatase activity in crude Escherichia coli cell extracts with molybdate, and inorganic phosphate was measured with a modified phosphomolybdate method. The screening system is general and can be used to screen GP enzyme libraries for novel donor and acceptor specificities. It was successfully applied to screen a residue E649 saturation mutagenesis library of Cellulomonas uda cellobiose phosphorylase (CP) for novel acceptor specificity. An E649C enzyme variant was found with novel acceptor specificity toward alkyl beta-glucosides and phenyl beta-glucoside. This is the first report of a CP enzyme variant with modified acceptor specificity. PMID:20188057

De Groeve, M R M; Tran, G H; Van Hoorebeke, A; Stout, J; Desmet, T; Savvides, S N; Soetaert, W

2010-06-01

152

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

153

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

154

Effects of the isoflavone puerarin and its glycosides on melanogenesis in B16 melanocytes  

Microsoft Academic Search

We investigated the effects of puerarin (8-C-glucosyl-7,4?-dihydroxy isoflavone), an isoflavone found in Kudzu roots (Pueraria lobata), and its glycosides (enzymatically synthesised, water-soluble derivatives of puerarin) on melanogenesis in vitro. Puerarin\\u000a and its glycosides reduced mushroom tyrosinase activity by 88 and 67% at 4.8 mM, respectively, in a concentration-dependent\\u000a manner. The puerarin glycosides were less effective than puerarin at the same concentration

Young-Mi Choi; Hee-jin Jun; Kevin Dawson; Raymond L. Rodriguez; Mi Ran Roh; Jungae Jun; Chung-Hyo Choi; Jae-Hoon Shim; ChoongHwan Lee; Sang Jun Lee; Kwan-Hwa Park; Sung-Joon Lee

2010-01-01

155

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

156

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

157

MATE2 Mediates Vacuolar Sequestration of Flavonoid Glycosides and Glycoside Malonates in Medicago truncatula[C][W][OA  

PubMed Central

The majority of flavonoids, such as anthocyanins, proanthocyanidins, and isoflavones, are stored in the central vacuole, but the molecular basis of flavonoid transport is still poorly understood. Here, we report the functional characterization of a multidrug and toxin extrusion transporter (MATE2), from Medicago truncatula. MATE 2 is expressed primarily in leaves and flowers. Despite its high similarity to the epicatechin 3?-O-glucoside transporter MATE1, MATE2 cannot efficiently transport proanthocyanidin precursors. In contrast, MATE2 shows higher transport capacity for anthocyanins and lower efficiency for other flavonoid glycosides. Three malonyltransferases that are coexpressed with MATE2 were identified. The malonylated flavonoid glucosides generated by these malonyltransferases are more efficiently taken up into MATE2-containing membrane vesicles than are the parent glycosides. Malonylation increases both the affinity and transport efficiency of flavonoid glucosides for uptake by MATE2. Genetic loss of MATE2 function leads to the disappearance of leaf anthocyanin pigmentation and pale flower color as a result of drastic decreases in the levels of various flavonoids. However, some flavonoid glycoside malonates accumulate to higher levels in MATE2 knockouts than in wild-type controls. Deletion of MATE2 increases seed proanthocyanidin biosynthesis, presumably via redirection of metabolic flux from anthocyanin storage. PMID:21467581

Zhao, Jian; Huhman, David; Shadle, Gail; He, Xian-Zhi; Sumner, Lloyd W.; Tang, Yuhong; Dixon, Richard A.

2011-01-01

158

Reversing vasectomy.  

PubMed

Advances in surgical techniques have made the reversal of vasectomy a realistic prospect. Currently, some 3% of patients request the reversal of vasectomy. Reversal techniques include macroscopic vasovasostomy, vasovasostomy with optical loupe magnification, and microsurgical methods. All of these methods have demonstrated acceptable rates of patency and pregnancy. Common to the success of these methods is the accurate apposition of mucosa to mucosa. The results of uniting the straight segments of the vas are better than those obtained with vasoepididymostomy. Recent reports indicate up to 80% patency and 30% pregnancy rates after macrosurgical anastomosis and up to 90% patency and 40% pregnancy rates after microsurgery. Operation failure could result from the following: poor anastomotic surgical technique, infection leading to fibrosis, formation of anastomotic sperm and suture granulomas, more than 10 years elapsing between the vasectomy and the reversal, and the removal of either too long a portion of the vas or part of the convoluted portion of the vas during the initial vasectomy. Although uncommon, some complications during the reversal procedure have been reported. As the reports indicate, pregnancy and patency differ significantly. Several explanations exist: 1) semen quality after reversal may be poor; 2) a secondary anastomotic stricture in the vas may gradually develop; 3) pressure mediated local changes may affect the testis and epididymis; 4) there might be a an injury to the sympathetic nerve fibers in the vas sheath; 5) antibodies to sperm may be present. While reversal is possible, the article cautions that the public should not consider vasectomy a reversible method of birth control. PMID:1392787

Banerjee, A K; Simpson, A

1992-05-01

159

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

160

Immunomodulatory action of triterpene glycosides isolated from the sea cucumber Actinocucumis typica. Structure-activity relationships.  

PubMed

Stimulation of lysosomal activity and ROS formation in mouse peritoneal macrophages by five triterpene glycosides, typicosides A1 (1), A2 (2), B1 (3), C1 (4) and C2 (5) has been studied and compared with their cytotoxic activities. Glycosides 1-3 possess moderate activities, but the most cytotoxic glycoside 5 is not active. Typicoside C1 (4), with low toxicity, was proved to be the most active concerning stimulation of ROS formation. This is the first example of a triterpene glycoside from sea cucumbers with low cytotoxicity, but which demonstrates a strong immunostimulatory effect on mouse peritoneal macrophages in vitro. PMID:25115075

Pislyagin, Evgeny A; Aminin, Dmitry L; Silchenko, Alexandra S; Avilov, Sergey A; Andryjashchenko, Pelageya V; Kalinin, Vladimir I; Padmakumar, Krishna

2014-06-01

161

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

162

Glycosides from marine sponges (Porifera, Demospongiae): structures, taxonomical distribution, biological activities and biological roles.  

PubMed

Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

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

2012-08-01

163

Anti-acetylcholinesterase and anti-amnesic activities of a pregnane glycoside, cynatroside B, from Cynanchum atratum.  

PubMed

We previously reported that seven pregnane glycosides including cynatroside B isolated from the roots of Cynanchum atratum significantly inhibited acetylcholinesterase (AChE) activity. In the present study, we have characterized the mode of AChE inhibition of cynatroside B, the most potent of these isolated pregnane glycoside inhibitors. We have also examined the anti-amnesic activity of cynatroside B. Cynatroside B inhibited AChE activity in a dose-dependent manner and its IC50 value was 3.6 microM. The mode of AChE inhibition by cynatroside B was reversible and non-competitive in nature. Moreover, cynatroside B (1.0 mg/kg body weight i.p.) significantly ameliorated memory impairments induced in mice by scopolamine (1.0 mg/kg body weight s.c.) as measured in the passive avoidance and the Morris water maze tests. We suggest, therefore, that cynatroside B has both anti-AChE and anti-amnesic activities that may ultimately hold significant therapeutic value in alleviating certain memory impairments observed in Alzheimer's disease. PMID:15678366

Lee, Ki Yong; Yoon, Jeong Seon; Kim, Eun Sil; Kang, So Young; Kim, Young Choong

2005-01-01

164

Beta-D-glucosyl and alpha-D-galactosyl Yariv reagents: syntheses from p-nitrophenyl-D-glycosides by transfer reduction using ammonium formate.  

PubMed

Yariv beta-D-glucosyl (4a) and Yariv alpha-d-galactosyl (4b) reagents are multivalent phenylglycosides. The beta-D-glucosyl reagent is considered diagnostic for arabinogalactan proteins (AGPs) to which it can reversibly bind, stain, and precipitate. The alpha-D-galactosyl reagent does not bind AGPs and is used as a control. In a new strategy, we accomplished the large scale synthesis of the Yariv reagents in one continuous step by a transfer reduction method and without a need for any specialized apparatus. As the starting material, p-nitrophenyl-D-glycosides (1) were reduced to p-aminophenyl-D-glycosides (2) using ammonium formate as the hydrogen donor. The excess formate was converted to formic acid and ammonia, which then were removed from the reaction by simple distillation. Without isolation, p-aminophenyl-D-glycosides were diazotized (3) and coupled to phloroglucinol to give the Yariv reagents in approximately 40% yield. AGPs are a major component of gum arabic, an emulsifying agent widely used in the food and pharmaceutical industries. Increasing interest in AGPs prompted the development of a relatively easy and inexpensive method for the synthesis of these reagents. PMID:15675787

Basile, Dominick V; Ganjian, Iraj

2004-12-15

165

Quantitative determination of flavonoids and cycloartanol glycosides from aerial parts of Sutherlandia frutescens (L.) R. BR. by using LC-UV\\/ELSD methods and confirmation by using LC–MS method  

Microsoft Academic Search

This paper describes the first analytical method for the determination of four flavonoids (sutherlandins A–D) and four cycloartanol glycosides (sutherlandiosides A–D) from the aerial parts of Sutherlandia frutescens (L.) R. Br. A separation by HPLC was achieved by using a reversed phase (RP-18) column, PDA with ELS detection, and a water\\/acetonitrile gradient as the mobile phase. The wavelength used for

Bharathi Avula; Yan-Hong Wang; Troy J. Smillie; Xiang Fu; Xing Cong Li; Wilfred Mabusela; James Syce; Quinton Johnson; William Folk; Ikhlas A. Khan

2010-01-01

166

Separation and characterization of soluble esterified and glycoside-bound phenolic compounds in dry-blanched peanut skins by liquid chromatography-electrospray ionization mass spectrometry.  

PubMed

A large variety of soluble phenolic compounds, including phenolic acids (hydroxybenzoic acids, ethyl protocatechuate, and hydroxycinnamic acids, as well as phenylacetic acid and phenyllactic acid), stilbenes (trans-piceatannol and trans-3,3',5,5'-tetrahydroxy-4'-methoxystilbene), flavan-3-ols (e.g., (-)-epicatechin, (+)-catechin, (-)-epiafzelechin, and their polymers (the proanthocyanidins, PACs)), other flavonoids (e.g., isoflavones, flavanols, and flavones), and biflavonoids, were released from esters and glycosides by base/acid hydrolysis and identified in acetonic extracts of dry-blanched peanut skins (PS). Reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with electrospray ionization mass spectrometry (ESI-MS(n)) was applied to separate and identify the phenolic constituents. Tentative identification of the separated phenolics was based on molecular ions and MS(n) fragmentation patterns acquired by ESI-MS in the negative-ion mode. Identification of free phenolic acids, stilbenes, and flavonoids was also achieved by commercial standards and by published literature data. Quantification was performed on the basis of peak areas of the UV signals from the HPLC chromatograms and calibration curves of the commercial standards. The flavonoids of PS exist mostly in glycoside-bound forms, but the aglycones can be liberated upon acid hydrolysis. PS contain significantly more PACs compared to free phenolic compounds: PAC monomers to tetramers constituted 92.0% of esterified phenolic compounds. The PAC monomer ((+)-catechin) and dimers are the main phenolics released from glycosides and account for 31.7 and 59.1%, respectively, of the total glycoside-bound phenolic compounds. PMID:25354220

Ma, Yuanyuan; Kosi?ska-Cagnazzo, Agnieszka; Kerr, William L; Amarowicz, Ryszard; Swanson, Ruthann B; Pegg, Ronald B

2014-11-26

167

Hyperosmotic hemolysis and antihemolytic activity of the saponin fraction and triterpene glycosides from Panax ginseng C. A. Meyer.  

PubMed

A saponin fraction and triterpene glycosides Rb1, Rb2 and Rg1 from Panax ginseng C. A. Meyer (saponins) were shown to inhibit the hyperosmotic hemolysis of erythrocytes. Using scanning electron microscopy and light scattering, saponins were found to restore the shape of the cells by inhibiting their contraction and the formation of echinocytes and microspherocytes. Scanning microcalorimetry demonstrated that an increase in osmomolarity and ionic strength of the medium eliminated structural transitions of erythrocyte ghost membranes. The hyperosmotic conditions were shown to cause the destruction of the erythrocyte membrane skeleton, except for the cytoplasmic and membrane domains of band 3 proteins. Saponins changed the parameters of all membrane structural transitions, induced new reversible transitions in the membranes and eliminated the ripple phase of dipalmitoylphosphatidylcholine. The mechanism of the antihemolytic action is discussed based on the bilayer couple model hypothesis. PMID:11093585

Kim YuA; Akoev, V R; Elemesov, R E

2000-01-01

168

Two new flavonoid glycosides from the halophyte Limonium franchetii.  

PubMed

Two new flavonoid glycosides, named quercetin-3-O-(2?-O-tigloyl)-?-L-rhamnopyranoside (1) and quercetin-3-O-(3?-O-tigloyl)-?-L-rhamnopyranoside (2), together with 10 known flavonoids (3-12), were isolated from the whole plant of the halophyte Limonium franchetii. Their structures were elucidated on the basis of extensive spectroscopic analysis including 2D NMR and HR-EI-MS. In addition, primary bioassays showed that compound 1 had moderate cytotoxic activity against rat C6 glioma cell lines. PMID:24597719

Kong, Na-Na; Fang, Sheng-Tao; Wang, Jian-Hua; Wang, Zhen-Hua; Xia, Chuan-Hai

2014-01-01

169

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

170

A first new antimalarial pregnane glycoside from Gongronema napalense  

PubMed Central

As a part of the UIC-based ICBG project in Laos, plants were collected based on ethnomedical interviews and evaluated for antimalarial activity. A CHCl3 extract from the vine of Gongronema napalense (Wall.) Decne. (Asclepiadaceae) showed promising anti-malarial activity while exhibiting low levels of cytotoxicity and was thus followed up with further fractionation and biological evaluation. Bioassay-guided fractionation led to the isolation of a new steroidal glycoside, gongroneside A, which showed antimalarial activity in vitro with an IC50 value of 1.60 and 1.39 ?M against the Plasmodium falciparum D6 and W2 clones, respectively. PMID:23653676

Libman, Amey; Zhang, Hongjie; Ma, Cuiying; Southavong, Bounhong; Sydara, Kongmany; Bouamanivong, Somsanith; Tan, Ghee T.; Fong, Harry H. S.; Soejarto, D. Doel

2010-01-01

171

[New flavonoid-glycosides from Crataegus monogyna and Crataegus pentagyna].  

PubMed

From the leaves and flowers of Crataegus monogyna and C. Pentagyna six new flavonoid-C- and O-glycosides respectively have been isolated and identified as 2''-O-rhamnosyl-orientin, 2''-O-rhamnosyl-isoorientin, 2''-O-rhamnosyl-isovitexin, rutin, spiraeosid, 8-methoxy-kämpferol and 8-methoxy-kämpferol-3-O-glucoside. The structure of O-rhamnosyl-vitexin and O-acetyl-O-rhamnosyl-vitexin isolated previously, have been elucidated unambigiously mainly by NMR- and MS-spectroscopy. PMID:17402083

Nikolov, N; Seligmann, O; Wagner, H; Horowitz, R M; Gentili, B

1982-01-01

172

Additional new minor cucurbitane glycosides from Siraitia grosvenorii.  

PubMed

Continuous phytochemical studies of the crude extract of Luo Han Guo (Siraitia grosvenorii) furnished three additional new cucurbitane triterpene glycosides, namely 11-deoxymogroside V, 11-deoxyisomogroside V, and 11-deoxymogroside VI. The structures of all the isolated compounds were characterized on the basis of extensive NMR and mass spectral data as well as hydrolysis studies. The complete ¹H- and ¹³C-NMR spectral assignments of the three unknown compounds are reported for the first time based on COSY, TOCSY, HSQC, and HMBC spectroscopic data. PMID:24662081

Prakash, Indra; Chaturvedula, Venkata Sai Prakash

2014-01-01

173

A new phenanthrene glycoside and other constituents from Dioscorea opposita.  

PubMed

Phytochemical investigation of the rhizome of Dioscorea opposita has led to the isolation of a new phenanthrene glycoside, 3,4,6-trihydroxyphenanthrene-3-O-beta-D-glucopyranoside (1), and five known compounds, soyacerebroside I (2), adenosine (3), beta-sitosterol (4), palmitic acid (5) and palmitoyloleoylphosphatidylcholine (6). Their structures were determined by spectroscopic methods, including 1D- and 2D-NMR. Compounds 1-6 exhibited no antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata and C. tropicalis. PMID:15467243

Sautour, Marc; Mitaine-Offer, Anne-Claire; Miyamoto, Tomofumi; Wagner, Hildebert; Lacaille-Dubois, Marie-Aleth

2004-10-01

174

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

175

Triterpenoids and a triterpene glycoside from Schefflera bodinieri leaves  

Microsoft Academic Search

Two novel triterpenoids and a triterpene glycoside have been isolated from the leaves of Schefflera bodinieri. They are 3-oxo-20-demethylisoaleuritolic-14(15)-ene-28,29-dioic acid, 28-O-[?-l-rhamnopyranosyl(1?4)-O-?- d-glucopyranosyl(1?6)-]-O-?-d-glucopyranoside of 3-oxo-20-demethylisoaleuritic-14(15)-ene-28,29-dioic acid and 3?-hydroxyl-20-demethylisoaleuritolic-14(15)-ene-28,30-dioic acid. The known compounds, d-sorbitol, stigmasterol-3-O-?-d-glucose and two trisaccharides, were also isolated from the leaves. The structures were established on the basis of chemical and spectral evidence.

Min Zhu; J. David Phillipson; Pam M. Greengrass; Norman G. Bowery

1996-01-01

176

Flavonoid Glycosides from Arnica montana and Arnica chamissonis.  

PubMed

Five flavonoid glycosides were identified from flowers of ARNICA MONTANA, four from A. CHAMISSONIS subsp. FOLIOSA var. INCANA. The structures were established on the basis of total acid hydrolysis and spectral data (UV, (1)H-NMR, (13)C-NMR, MS) as hispidulin 7- O-beta-glucoside, isorhamnetin 3- O-beta-glucoside, 3- O-beta- D-glucopyranosides of spinacetin, 6-methoxykaempferol and patuletin and querectin 3- O-(6''- O-acetyl)-beta- D-glucopyranoside. The latter compound can serve as distinctive marker between these two ARNICA species. The (1)H-NMR spectra in CD (3)OD are discussed. PMID:17269063

Merfort, I; Wendisch, D

1987-10-01

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

Triterpenoid glycosides from the leaves of two cultivars of Medicago polymorpha L.  

PubMed

The saponin composition of leaves from the Medicago polymorpha cultivars 'Santiago' and 'Anglona' belonging to the botanical varieties brevispina and vulgaris, respectively, was investigated by a combination of chromatographic, spectroscopic, and spectrometric techniques. Several compounds were detected and quantitated by HPLC analysis using the external standard method. Twelve triterpene saponins (1-12) were purified by reverse-phase chromatography and their structures elucidated by spectroscopic (1D and 2D NMR, ESI-MS/MS) and chemical methods. They were identified as glycosides of echinocystic acid, hederagenin, caulophyllogenin, bayogenin, and soyasapogenol B. Two of them (2, 10) were previously reported in M. polymorpha; five of them (4, 6, 7, 9, 12) were already identified in other Medicago species; and three of them (1, 8, 11) were found in other plant genera. The two saponins identified as 3-O-?-L-arabinopyranosyl-28-O-[?-D-glucopyranosyl(1?6)?-D-glucopyranoside] echinocystic acid (3) and 3-O-?-L-arabinopyranosyl-28-O-?-D-glucopyranoside echinocystic acid (5) are newly identified natural compounds. The presence of echinocystic acid is reported here for the first time in the genus Medicago. Saponins from the cultivar 'Anglona' were characterized by a higher amount of echinocystic acid glycosydes, whereas saponins from the cultivar 'Santiago' were characterized by a higher amount of hederagenin glycosydes. PMID:21526796

Tava, Aldo; Pecetti, Luciano; Romani, Massimo; Mella, Mariella; Avato, Pinarosa

2011-06-01

180

Molecular cloning of glycoside hydrolase family 45 cellulase genes from brackish water clam Corbicula japonica.  

PubMed

We previously reported endogenous Glycoside Hydrolase Family (GHF) 9 beta-1,4-glucanase gene, CjCel9A, from common Japanese freshwater clam Corbicula japonica. Here we identified another endogenous beta-1,4-glucanase genes which belong to GHF45 (CjCel45A, CjCel45B). Both genes encode ORF of 627 bp corresponding to 208 amino acids. CjCel45A and CjCel45B are different in 5' and 3'-untranslated regions and six nucleotides in the ORF. CjCEL45 has only one GHF45 catalytic domain without any carbohydrate binding modules as is the case with other molluskan GHF45 enzymes. Phylogenetic analysis and genomic structure of CjCel45 gene implies that this gene is likely to be acquired from fungi by common ancestor of mollusks. Reverse transcription (RT)-PCR analysis and in situ hybridization revealed that CjCel45A is likely to be expressed in the secretory cells in the digestive gland, suggesting that this cellulase is produced in the same site as CjCEL9A. CjCEL45A was successfully expressed in E. coli cells and zymographic analysis of the recombinant CjCEL45A showed that CjCEL45A is a functional beta-1,4-glucanase. The finding of multiple cellulase genes in C. japonica strongly supports our hypothesis that this species function as a cellulose decomposer in estuarine environments. PMID:19266619

Sakamoto, Kentaro; Toyohara, Haruhiko

2009-04-01

181

Two new nor-triterpene glycosides from peruvian "Uña de Gato" (Uncaria tomentosa).  

PubMed

Two new 27-nor-triterpene glycosides, tomentosides A (1) and B (2), were isolated from Peruvian "Uña de Gato" (cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis and chemical interconversions. This is the first report of naturally occurring pyroquinovic acid glycosides. PMID:12608878

Kitajima, Mariko; Hashimoto, Ken-Ichiro; Yokoya, Masashi; Takayama, Hiromitsu; Sandoval, Manuel; Aimi, Norio

2003-02-01

182

Probing Electrostatic Interactions along the Reaction Pathway of a Glycoside Hydrolase: Histidine Characterization by NMR Spectroscopy  

E-print Network

Probing Electrostatic Interactions along the Reaction Pathway of a Glycoside Hydrolase: Histidine in this model glycoside hydrolase. Dissecting the complex network of electrostatic interac- tions within for directly interrogating the electrostatic interactions within a protein involves the measurement of the site

McIntosh, Lawrence P.

183

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

184

Antiproliferative, Cytotoxic and Hemolytic Activities of a Triterpene Glycoside from Psolus patagonicus and Its Desulfated Analog  

Microsoft Academic Search

Background: The major triterpene glycoside of the sea cucumber Psolus patagonicus and its desulfated analog were tested for their antiproliferative, cytotoxic and hemolytic activities, and their effect on NF-?B activation. Methods: The antiproliferative action of glycosides 1 and 2 were determined on 3 tumor cell lines. Their effect on the activation of NF-?B was evaluated by indirect immunofluorescence assay staining

Valeria P. Careaga; Carlos Bueno; Claudia Muniain; Laura Alché; Marta S. Maier

2009-01-01

185

Philinopsides E and F, two new sulfated triterpene glycosides from the sea cucumber Pentacta quadrangularis.  

PubMed

Two new sulfated triterpene glycosides, philinopside E (1) and F (2), have been isolated from the sea cucumber Pentacta quadrangularis. Their structures have been established by extensive spectral analysis (NMR and MS) and chemical evidence. Glycoside 1 showed significant cytotoxicity (Ed(50) 0.75-3.50 microg mL(-1)) against ten tumor cell lines. PMID:16644536

Zhang, Shi-Long; Li, Ling; Yi, Yang-Hua; Sun, Peng

2006-04-01

186

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

187

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

188

Acylated-oxypregnane glycosides from the roots of Araujia sericifera.  

PubMed

Twenty-three new acylated-oxypregnane glycosides were obtained from the roots of Araujia sericifera. (Asclepiadaceae). These glycosides were confirmed to be tetraglycosides possessing twelve known compounds, 12-O-benzoyllineolon, 12-O-benzoyldeacylmetaplexigenin, ikemagenin, kidjolanin, cynanchogenin, caudatin, rostratamine, penupogenin, 12-O-benzoylisolineolon, 12-O-tigloyldecylmetaplexigenin (incisagenin), 12-O-benzoyl-20-O-acetylsarcostin, 20-O-benzoyl-12-O-(E)-cinnamoyl-3 beta,5 alpha,8 beta,12 beta,14 beta,17 beta,20-heptahydroxy-(20S)-pregn-6-ene and ten new acylated-oxypregnanes, 12-O-benzoyl-20S-hydroxyisolineolon, 12-O-tigloyllineolon, 12-O-salicyloyllineolon, 12-O-salicyloyldeacylmetplexigenin, 12-O-benzoyl-3 beta,5 alpha,8 beta,12 beta,14 beta,17 beta-hexahydroxypregn-6-en-20-one, 12-O-benzoyl-19-benzoyloxydeacylmetapleligenin, 12-O-benzoyl-19-benzoyloxy-20-O-acetylsarcostin, 12-O-benzoyl-19-salicyloyloxy-20-O-acetylsarcostin, 12-O-benzoyl-5 alpha,6 alpha-epoxydeacylmetaplexigenin, and 12-O-benzoyl-5 alpha,6 alpha-epoxylineolon as their aglycones, using both spectroscopic and chemical methods. PMID:12951444

Warashina, Tsutomu; Noro, Tadakata

2003-09-01

189

Recovering glycoside hydrolase genes from active tundra cellulolytic bacteria.  

PubMed

Bacteria responsible for cellulose hydrolysis in situ are poorly understood, largely because of the relatively recent development of cultivation-independent methods for their detection and characterization. This study combined DNA stable-isotope probing (DNA-SIP) and metagenomics for identifying active bacterial communities that assimilated carbon from glucose and cellulose in Arctic tundra microcosms. Following DNA-SIP, bacterial fingerprint analysis of gradient fractions confirmed isotopic enrichment. Sequenced fingerprint bands and clone library analysis of 16S rRNA genes identified active bacterial taxa associated with cellulose-associated labelled DNA, including Bacteroidetes (Sphingobacteriales), Betaproteobacteria (Burkholderiales), Alphaproteobacteria (Caulobacteraceae), and Chloroflexi (Anaerolineaceae). We also compared glycoside hydrolase metagenomic profiles from bulk soil and heavy DNA recovered from DNA-SIP incubations. Active populations consuming [(13)C]glucose and [(13)C]cellulose were distinct, based on ordinations of light and heavy DNA. Metagenomic analysis demonstrated a ?3-fold increase in the relative abundance of glycoside hydrolases in DNA-SIP libraries over bulk-soil libraries. The data also indicate that multiple displacement amplification introduced bias into the resulting metagenomic analysis. This research identified DNA-SIP incubation conditions for glucose and cellulose that were suitable for Arctic tundra soil and confirmed that DNA-SIP enrichment can increase target gene frequencies in metagenomic libraries. PMID:24983351

Pinnell, Lee J; Dunford, Eric; Ronan, Patrick; Hausner, Martina; Neufeld, Josh D

2014-07-01

190

A new glycosidic flavonoid from Jwarhar mahakashay (antipyretic) Ayurvedic preparation  

PubMed Central

The aqueous extract of Jwarhar mahakashay Ayurvedic preparation (from the roots of Hemidesmus indicus R. Br., Rubia cordifolia L., Cissampelos pareira L.; fruits of Terminalia chebula Retz., Emblica officinalis Gaertn., Terminalia bellirica Roxb., Vitis vinifera L., Grewia asiatica L., Salvadora persica L. and granules of Saccharum officinarum L.) has been used as a traditional antipyretic. Experimental studies confirmed its antipyretic–analgesic effect with very low ulcerogenicity and toxicity. Flavonoids, glycosides and tannins were later found to be present in the extract. Detailed chemical investigations were undertaken after hydrolysis of extract using spectroscopic and chromatography methods to determine its active chemical constituent. UV-Visible spectroscopy showed absorbance maxima at 220 and 276 nm, while fourier transform infra-red investigations indicated an end carboxylic O–H structure at 2940 cm?1 suggesting the presence of glycoside-linked flavonoids. Thin layer chromatography and high performance liquid chromatography also confirmed the possibility of at least one major and two minor compounds in this abstract. Detailed examination using gas chromatography-mass spectrometry led to the identification of the principal component as 2-(1-oxopropyl)-benzoic acid, which is quite similar to the active compound found in the standard drug Aspirin (2-acetyl-oxybenzoic acid). PMID:20814525

Gupta, Mradu; Shaw, B. P.; Mukherjee, A.

2010-01-01

191

Steviol Glycosides Modulate Glucose Transport in Different Cell Types  

PubMed Central

Extracts from Stevia rebaudiana Bertoni, a plant native to Central and South America, have been used as a sweetener since ancient times. Currently, Stevia extracts are largely used as a noncaloric high-potency biosweetener alternative to sugar, due to the growing incidence of type 2 diabetes mellitus, obesity, and metabolic disorders worldwide. Despite the large number of studies on Stevia and steviol glycosides in vivo, little is reported concerning the cellular and molecular mechanisms underpinning the beneficial effects on human health. The effect of four commercial Stevia extracts on glucose transport activity was evaluated in HL-60 human leukaemia and in SH-SY5Y human neuroblastoma cells. The extracts were able to enhance glucose uptake in both cellular lines, as efficiently as insulin. Our data suggest that steviol glycosides could act by modulating GLUT translocation through the PI3K/Akt pathway since treatments with both insulin and Stevia extracts increased the phosphorylation of PI3K and Akt. Furthermore, Stevia extracts were able to revert the effect of the reduction of glucose uptake caused by methylglyoxal, an inhibitor of the insulin receptor/PI3K/Akt pathway. These results corroborate the hypothesis that Stevia extracts could mimic insulin effects modulating PI3K/Akt pathway. PMID:24327825

Rizzo, Benedetta; Zambonin, Laura; Leoncini, Emanuela; Vieceli Dalla Sega, Francesco; Prata, Cecilia; Fiorentini, Diana; Hrelia, Silvana

2013-01-01

192

Prenylflavonol, acylated flavonol glycosides and related compounds from Epimedium sagittatum.  

PubMed

Chemical examination of the n-BuOH extract from the aerial parts of Epimedium sagittatum led to isolation of three prenylated flavonol glycosides sagittasine A-C, two acylated flavonol glycosides kaempferol-3-O-(2''-E-p-coumaroyl,4''-Z-p-coumaroyl)-alpha-l-rhamnopyranoside and kaempferol-3-O-(3''-Z-p-coumaroyl,4''-E-p-coumaroyl)-alpha-l-rhamnopyranoside, together with known flavonoids, flavonolignans, 2-phenoxychromones, a lignan, and aromatic acid derivatives. Flavonolignans were identified for the first time in this plant. The vasorelaxing properties of the n-BuOH extract of E. sagittatum and 13 isolated compounds were tested using pre-contracted rat aorta rings in an organ bath apparatus. The results indicated that the n-BuOH extract of E. sagittatum produced a partial endothelial nitric oxide-dependent vasorelaxation, with EC(50) of 0.16+/-0.03 mg/ml. However, the 13 compounds tested, generated only a mild or moderate relaxation, and did not possess significant vasorelaxing effect individually. PMID:17618659

Wang, Guei-Jane; Tsai, Tung-Hu; Lin, Lie-Chwen

2007-10-01

193

Reverse Osmosis  

NSDL National Science Digital Library

North Dakota State University presents the theories behind reverse osmosis and how it affects household water supplies. The site addresses the impurities which are removed by this process. It also speaks of testing, the process itself and even the disadvantages of this process. A fairly encompassing site is what amounts from the work done by the University, it gives a clear and concise viewpoint of this process.

2008-10-13

194

Evaluation of the content variation of anthraquinone glycosides in rhubarb by UPLC-PDA  

PubMed Central

Background Rhubarb is an important Chinese medicinal herb with a long history of over 2000 years and has been commonly used as a laxative. It is the radix and rhizome of Rheum officinale Baill., R. palmatum L. and R. tanguticum Maxim, all of which are mainly distributed in a broad region in the Tibetan plateau. Anthraquinone glycosides are a series of major active ingredients found in all three species. They are key intermediates in the anthraquinone secondary metabolism and the sennnoside biosynthesis. The variation of the anthraquinone glycoside content in rhubarb in response to specific factors remains an attractive topic. Results A simple and sensitive Ultra Performance Liquid Chromatography with Photo-Diode Array (UPLC-PDA) detector was developed for the simultaneous determination of six anthraquinone glycosides in rhubarb, i.e., aloeemodin-8-O-glucoside, rhein-8-O-glucoside, chrysophanol-1-O-glucoside, emodin-1-O-glucoside, chrysophanol-8-O-glucoside, emodin-8-O-glucoside. Twenty-seven batches from three species were submitted to the multi-component analysis. The results showed that the anthraquinone glycoside content varied significantly even within the same species. The results showed that the anthraquinone glycoside content varied significantly within the same species but not between different species. The PCA and content analysis results confirmed that the plant species has no obvious effect on the content variation. Neither was any significant correlation observed between the anthraquinone glycoside content and the geographic distribution of the rhubarb. Through correlational analysis, altitude was found to be the main factor that affects the anthraquinone glycoside content in rhubarb. Rhubarb grown at higher altitude has higher anthraquinone glycoside content. Conclusions This work provides a rapid, sensitive and accurate UPLC-PDA method for the simultaneous determination of six anthraquinone glycosides in rhubarb. The anthraquinone glycoside content varied significantly within the same species. The relationship of the anthraquinone glycoside content with plant species, geographic distribution and altitude were studied using correlational analysis, principal component analysis and spatial autocorrelation analysis through SPSS and ArcGIS. Plant species and geographic distribution were found not to affect the content of the six anthraquinone glycosides in rhubarb. The variations in the anthraquinone glycoside content were primarily due to the different altitude where the plant was grown. PMID:24160332

2013-01-01

195

Vasectomy reversal.  

PubMed

A vasovasostomy may be performed on an outpatient basis with local anesthesia, but also may be performed on an outpatient basis with epidural or general anesthesia. Local anesthesia is preferred by most of my patients, the majority of whom choose this technique. With proper preoperative and intraoperative sedation, patients sleep lightly through most of the procedure. Because of the length of time often required for bilateral microsurgical vasoepididymostomy, epidural or general anesthesia and overnight hospitalization are usually necessary. Factors influencing the preoperative choice for vasovasostomy or vasoepididymostomy in patients undergoing vasectomy reversal are considered. The preoperative planned choice of vasovasostomy or vasoepididymostomy for patients having vasectomy reversal described herein does not have the support of all urologists who regularly perform these procedures. My present approach has evolved as the data reported in Tables 1 and 2 have become available, but it may change as new information is evaluated. However, it offers a logical method for planning choices of anesthesia and inpatient or outpatient status for patients undergoing vasectomy reversal procedures. PMID:3811050

Belker, A M

1987-02-01

196

A comparison of sample preparation techniques for quantifying iridoid glycosides sequestered by lepidopteran larvae.  

PubMed

This study compared different methods of tissue preparation for extraction of iridoid glycosides sequestered by three species 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 of Plantago lanceolata, which produces two primary iridoid glycosides, aucubin and catalpol. Three methods of preparing the specimens before extraction in methanol were compared in all three species: 1) larvae were flash-frozen in liquid nitrogen, 2) larvae were macerated fresh in boiling methanol, or 3) larvae were macerated fresh in room temperature methanol. A set of J. coenia larvae was oven-dried before maceration as an additional treatment for this species only. Junonia coenia sequestered the most iridoid glycosides, while E. acrea sequestered the least, and S. congrua was intermediate. Estigmene acrea was poor at sequestering catalpol. Tissue preparation method only significantly influenced iridoid glycoside recovery from S. congrua, with maceration in room-temperature methanol being the most effective of the three methods. This study shows that treatment of insects prior to iridoid glycoside extraction can influence recovery of the compounds, and that the effects of treatment may vary among different species. PMID:21475987

Lampert, Evan C; Bowers, M Deane

2011-05-01

197

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

198

Phenolic Glycosides from the Twigs of Salix glandulosa.  

PubMed

As a part of an ongoing search for bioactive constituents from Korean medicinal plants, the phytochemical investigations of the twigs of Salix glandulosa afforded 12 new phenolic glycosides (1-12) and a known analogue (13). The structures of 1-13 were characterized by a combination of NMR methods ((1)H and (13)C NMR, (1)H-(1)H COSY, HMQC, and HMBC), chemical hydrolysis, and GC/MS. The absolute configuration of 13 [(1R,2S)-2-hydroxycyclohexyl-2'-O-trans-p-coumaroyl-?-d-glucopyranoside] was determined for the first time. Compounds 1-3, 6, and 7 exhibited inhibitory effects on nitric oxide production in lipopolysaccharide-activated murine microglial cells (IC50 values in the range 6.6-20.5 ?M). PMID:25098650

Kim, Chung Sub; Kwon, Oh Wook; Kim, Sun Yeou; Choi, Sang Un; Kim, Jae Yoon; Han, Ji Young; Choi, Soo Im; Choi, Jong Gil; Kim, Ki Hyun; Lee, Kang Ro

2014-08-01

199

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

200

Flavonol glycosides from the south African medicinal plant Sutherlandia frutescens.  

PubMed

Phytochemical investigation of the leaves of Sutherlandia frutescens led to the isolation of four new 3-hydroxy-3-methylglutaroyl-containing flavonol glycosides, sutherlandins A-D ( 1- 4). Their structures were elucidated by chemical and spectroscopic methods as quercetin 3- O- beta- D-xylopyranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 1), quercetin 3- O- beta- D-apiofuranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 2), kaempferol 3- O- beta- D-xylopyranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 3), and kaempferol 3- O- beta- D-apiofuranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 4). PMID:19670162

Fu, Xiang; Li, Xing-Cong; Wang, Yan-Hong; Avula, Bharathi; Smillie, Troy J; Mabusela, Wilfred; Syce, James; Johnson, Quinton; Folk, William; Khan, Ikhlas A

2010-02-01

201

Aromatic glycosides from the flower buds of Lonicera japonica.  

PubMed

Six new glycosides (1-6) have been isolated from the flower buds of Lonicera japonica. Their structures including the absolute configurations were determined by spectroscopic and chemical methods as ( - )-2-hydroxy-5-methoxybenzoic acid 2-O-?-d-(6-O-benzoyl)-glucopyranoside (1), ( - )-4-hydroxy-3,5-dimethoxybenzoic acid 4-O-?-d-(6-O-benzoyl)-glucopyranoside (2), ( - )-(E)-3,5-dimethoxyphenylpropenoic acid 4-O-?-d-(6-O-benzoyl)-glucopyranoside (3), ( - )-(7S,8R)-(4-hydroxyphenylglycerol 9-O-?-d-[6-O-(E)-4-hydroxy-3,5-dimethoxyphenylpropenoyl]-glucopyranoside (4), ( - )-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol 9-O-?-d-[6-O-(E)-4-hydroxy-3,5-dimethoxyphenylpropenoyl]-glucopyranoside (5), and ( - )-4-hydroxy-3-methoxyphenol ?-d-{6-O-[4-O-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (6), respectively. PMID:23614462

Wang, Fang; Jiang, Yue-Ping; Wang, Xiao-Liang; Wang, Su-Juan; Bu, Peng-Bin; Lin, Sheng; Zhu, Cheng-Gen; Shi, Jian-Gong

2013-01-01

202

Two new lignan glycosides from the seeds of Cuscuta chinensis.  

PubMed

Two new lignan glycosides, 2'-hydroxyl asarinin 2'-O-?-D-glucopyranoside (cuscutoside C, 1) and 2'-hydroxyl asarinin 2'-O-?-D-apiofuranosyl-(1 ? 2)-[?-D-glucopyranosyl-(1 ? 6)]-?-D-glucopyranoside (cuscutoside D, 2), were isolated from the seeds of Cuscuta chinensis Lam., along with six known compounds, 2'-hydroxyl asarinin 2'-O-?-D-glucopyranosyl-(1 ? 6)-?-D-glucopyranoside (3), 2'-hydroxyl asarinin 2'-O-?-D-apiofuranosyl-(1 ? 2)-?-D-glucopyranoside (cuscutoside A, 4), kaempferol 3,7-di-O-?-D-glucopyranoside (5), 5-caffeoyl quinic acid (6), 4-caffeoyl quinic acid (7), and cinnamic acid (8). Their structures were elucidated on the basis of spectroscopic analyses including HR-ESI-MS, ESI-MS/MS, (1)H and (13)C NMR, HSQC, HMBC, and TOCSY. PMID:21061214

He, Xiang-Hui; Yang, Wen-Zhi; Meng, A-Hui; He, Wen-Ni; Guo, De-An; Ye, Min

2010-11-01

203

A new hemiterpene glycoside from the ripe tomatoes.  

PubMed

[Figure: see text]A new hemiterpene glycoside (1) was isolated from ripe tomatoes (the fruit of Lycopersicon esculentum, Solanaceae) along with eight known compounds. The chemical structure of 1 was determined to be 2-methylbutan-1-ol ?-d-glucopyranosyl-(1 ? 6)-?-d-glucopyranoside, based on spectroscopic data as well as chemical evidence. In addition, the radical-scavenging activities of the isolated compounds on the free radical of 1,1-diphenyl-2-picrylhydrazyl were examined. Among the tested compounds, tryptophan, 4-O-?-d-glucopyranosyl caffeic acid and dihydro-p-coumaryl alcohol ?-O-?-d-glucopyranoside demonstrated 42.0%, 50.1% and 76.0% scavenging activities, respectively, at a concentration of 0.5 mM. PMID:25421719

Ono, Masateru; Yasuda, Shin; Shiono, Yuki; Furusawa, Chisato; Inaba, Shinya; Tanaka, Takayuki; Ikeda, Tsuyoshi; Nohara, Toshihiro

2015-02-01

204

Two new anthraquinone glycosides from the roots of Rheum palmatum.  

PubMed

Two new anthraquinone glycosides, named 1-methyl-8-hydroxyl-9,10-anthraquinone-3-O-?-D-(6'-O-cinnamoyl)glucopyranoside (1) and rhein-8-O-?-D-[6'-O-(3''-methoxyl malonyl)]glucopyranoside (2), have been isolated from the roots of Rheum palmatum, together with seven known compounds, rhein-8-O-?-D-glucopyranoside (3), physcion-8-O-?-D-glucopyranoside (4), chrysophanol-8-O-?-D-glucopyranoside (5), aleo-emodin-8-O-?-D-glucopyranoside (6), emodin-8-O-?-D-glucopyranoside (7), aleo-emodin-?-O-?-D-glucopyranoside (8), and emodin-1-O-?-D-glucopyranoside (9). Their structures were elucidated on the basis of chemical and spectral analysis. PMID:21128142

Zhang, Cun; Li, Li; Xiao, Yong-Qing; Tian, Guo-Fang; Chen, Dong-Dong; Wang, Yun; Li, Yu-Tian; Huang, Wen-Qian

2010-12-01

205

Two new anthraquinone glycosides from the roots of Rheum palmatum  

Microsoft Academic Search

Two new anthraquinone glycosides, named 1-methyl-8-hydroxyl-9,10-anthraquinone-3-O-?-d-(6?-O-cinnamoyl)glucopyranoside (1) and rhein-8-O-?-d-[6?-O-(3?-methoxyl malonyl)]glucopyranoside (2), have been isolated from the roots of Rheum palmatum, together with seven known compounds, rhein-8-O-?-d-glucopyranoside (3), physcion-8-O-?-d-glucopyranoside (4), chrysophanol-8-O-?-d-glucopyranoside (5), aleo-emodin-8-O-?-d-glucopyranoside (6), emodin-8-O-?-d-glucopyranoside (7), aleo-emodin-?-O-?-d-glucopyranoside (8), and emodin-1-O-?-d-glucopyranoside (9). Their structures were elucidated on the basis of chemical and spectral analysis.

Cun Zhang; Li Li; Yong-Qing Xiao; Guo-Fang Tian; Dong-Dong Chen; Yun Wang; Yu-Tian Li; Wen-Qian Huang

2010-01-01

206

New Flavonoid Glycosides from Arnicae Flos DAB 91.  

PubMed

Five flavonoid glycosides were identified from flowers of Arnica montana, ten from A. CHAMISSONIS subsp. FOLIOSA var. INCANA. The structures were established on the basis of acid hydrolysis and spectral data (UV, NMR, MS) as the 7-beta-glucosides of pectolinarigenin, apigenin, and chrysoeriol; luteolin 3'- O-beta-glucoside; the 3-beta-glucuronides of kaempferol, isorhamnetin, and 6-methoxykaempferol; the 3,7-di-beta-glucosides of quercetin and patuletin; the 3-beta-glucosides of betuletol and quercetagetin 6,3',4'-trimethyl ether; and the 7-[6''- O-(2-methylbutyryl)]=glucosides of luteolin and eupafolin. The latter four are new natural compounds. Differences between these two ARNICA species are discussed. PMID:17226484

Merfort, I; Wendisch, D

1992-08-01

207

Triterpene glycosides from the leaves of Pittosporum angustifolium.  

PubMed

Phytochemical investigation of the leaves of Pittosporum angustifolium resulted in the isolation and structural elucidation of nine new triterpene saponins, named pittangretosides A-I (1-9), together with a known compound (10). Mainly by NMR and HRESIMS experiments, eight compounds were identified as A1-barrigenol glycosides (1-7, 10), whereas two compounds exhibited an unusual 17,22-seco-backbone of oleanolic acid (8, 9). All compounds were evaluated for their in vitro cytotoxicities against human urinary bladder carcinoma cells (5637). Only compounds with an angeloyl-residue at C-22 of the aglycone (1-4 and 10) showed antiproliferative effects with IC50 values of 4.1, 5.2, 2.1, 17.9, and 2.4 µM, respectively. PMID:24046217

Bäcker, Christian; Jenett-Siems, Kristina; Siems, Karsten; Wurster, Martina; Bodtke, Anja; Chamseddin, Chamseddin; Crüsemann, Max; Lindequist, Ulrike

2013-10-01

208

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

209

Steroidal glycosides from the underground parts of Yucca glauca and their cytotoxic activities.  

PubMed

Six steroidal glycosides and 14 known compounds were isolated from the underground parts of Yucca glauca (Agavaceae). Their structures were determined from extensive spectroscopic analysis, including analysis of two-dimensional NMR data, and from chemical transformations. The compounds were also evaluated for cytotoxic activities against HL-60 human leukemia cells and A549 human lung adenocarcinoma cells. Four spirostanol glycosides and three furostanol glycosides exhibited cytotoxic activities against both HL-60 and A549 cells. Two of the compounds induced apoptosis in HL-60 cells. PMID:24612536

Yokosuka, Akihito; Suzuki, Tomoka; Tatsuno, Satoru; Mimaki, Yoshihiro

2014-05-01

210

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

211

Two new cytotoxic triterpene glycosides from the sea cucumber Holothuria scabra.  

PubMed

Two new triterpene glycosides, scabraside A (1) and B (2), and a structurally known compound (3), were isolated from the sea cucumber Holothuria scabra (Holothuriidae) collected from the South China Sea. Structure of these compounds was elucidated by spectroscopic and chemical methods. The glycosides 1 and 2 exhibit the same common structural features, i. e., the presence of 12- and 17-hydroxy groups in the holostane-type triterpene aglycone with a 9(11)-ene bond, but are different in the side chains of the triterpene aglycone. The glycosides 1 and 2 had significant in vitro cytotoxicity against four human tumor cell lines in comparison to 10-hydroxycamptothecin. PMID:19598081

Han, Hua; Yi, Yanghua; Xu, Qiangzhi; La, Mingping; Zhang, Hongwei

2009-12-01

212

Analysis of supercooling-facilitating (anti-ice nucleation) activity of flavonol glycosides.  

PubMed

Deep supercooling xylem parenchyma cells (XPCs) of katsura tree (Cercidiphyllum japonicum) contain four kinds of flavonol glycosides with high supercooling-facilitating (anti-ice nucleation) activities. These flavonol glycosides have very similar structures, but their supercooling-facilitating activities are very different. In this study, we analyzed the supercooling-facilitating activities of 12 kinds of flavonol glycosides in order to determine the chemical structures that might affect supercooling-facilitating activity. All of the flavonol glycosides tested showed supercooling-facilitating activity, although the magnitudes of activity differed among the compounds. It was clear that the combination of the position of attachment of the glycosyl moiety, the kind of attached glycosyl moiety and the structure of aglycone determined the magnitude of anti-ice nucleation activity. However, there is still some ambiguity preventing the exact identification of features that affect the magnitude of supercooling-facilitating activity. PMID:20040364

Kasuga, Jun; Fukushi, Yukiharu; Kuwabara, Chikako; Wang, Donghui; Nishioka, Atsushi; Fujikawa, Emiko; Arakawa, Keita; Fujikawa, Seizo

2010-04-01

213

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

214

Resin glycosides from the yellow-skinned variety of sweet potato (Ipomoea batatas).  

PubMed

Native to tropical America, Ipomoea batatas has been cultivated for over 5000 years in Mexico. The yellow-skinned tuber crop variety, with an orange flesh, has a higher nutritional value than potato. Raw sweet potato can cause a purge due to its resin glycoside content. Purification of the chloroform-soluble resin glycosides from the roots of this variety was accomplished by preparative-scale HPLC, which allowed for the collection of six oligosaccharides, batatin VII (1) and batatinosides VII-IX (2-4), all of novel structure, together with the known resin glycosides pescaprein I and batatinoside IV. High-field NMR spectroscopy and FAB mass spectrometry were used to characterize each structure, identifying operculinic acid A for compounds 2 and 4, and simonic acid B for 3, as their pentasaccharide glycosidic cores. Batatin VII (1) represents a dimer of the know batatinoside IV, consisting of two units of simonic acid B. PMID:24053411

Rosas-Ramírez, Daniel; Pereda-Miranda, Rogelio

2013-10-01

215

Cytotoxic holostane-type triterpene glycosides from the sea cucumber Pentacta quadrangularis.  

PubMed

Two new holostane-type triterpene glycosides, named pentactasides I (1) and II (2), and a new natural product, pentactaside III (3), together with two known glycosides, philinopsides A (4) and B (5), were isolated from the sea cucumber Pentacta quadrangularis. Their structures were elucidated by extensive spectroscopic analysis and chemical evidences. Compounds 1 and 2 possess the same trisaccharide moiety which is a rare structural feature among naturally occurring sea cucumber glycosides and has been infrequently reported, while 3 is a sulfated diglycoside. All the glycosides showed significant in vitro cytotoxicities against six tumor cell lines (P-388, A-549, MCF-7, MKN-28, HCT-116, and U87MG) with IC(50) in the range of 0.60-3.95 µM. PMID:20425691

Han, Hua; Xu, Qiang-Zhi; Tang, Hai-Feng; Yi, Yang-Hua; Gong, Wei

2010-11-01

216

A novel flavonoid C-glycoside from Sphaeranthus indicus L. (family Compositae).  

PubMed

A novel flavonoid C-glycoside, 5-hydroxy-7-methoxy-6-C-glycosylflavone (1), was isolated from the aerial part of Sphaeranthus indicus. Its structure was elucidated by spectroscopic methods. PMID:17978758

Mishra, Bhuwan B; Yadav, S B; Singh, Rakesh K; Tripathi, Vyasji

2007-01-01

217

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

218

Direct and correlated responses to selection on iridoid glycosides in Plantago lanceolata L  

Microsoft Academic Search

Plantago lanceolata L. (ribwort plantain) produces two costly terpenoid secondary plant compounds, the iridoid glycosides aucubin and catalpol. We performed an artificial selection experiment to investigate direct and correlated responses to selection on the constitutive level of iridoid glycosides in the leaves for four generations. Estimated realized heritabilities (+\\/-SE) were 0.23 +\\/- 0.07 and 0.23 +\\/- 0.04 for upward and

H. B. Marak; A. Biere; J. M. M. Van Damme

2000-01-01

219

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

220

Components of the ether-insoluble resin glycoside-like fraction from Cuscuta chinensis  

Microsoft Academic Search

A trisaccharide and four new glycosidic acids, named cuscutic acids A-D, along with known organic acids, acetic acid, propionic acid, (2S)-2-methylbutyric acid, tiglic acid, (2R, 3R)-nilic acid, (11S) convolvulinolic acid and (11S)-jalapinolic acid have been isolated from the alkaline hydrolysate of the ether-insoluble resin glycoside-like fraction of the seeds of Cuscuta chinensis. The compounds were characterized on the basis of

Xiao-Ming Du; Toshio Kawasaki; Yong-Tian Guo; Kazumoto Miyahara

1998-01-01

221

A new biologically active flavonol glycoside from the seeds of Abrus precatorius Linn  

Microsoft Academic Search

A new flavonol glycoside m.f. C 29 H 34 O 16 , m.p. 260-262°C, [M] + 638 (EIMS) was separated from the chloroform soluble fraction of the concentrated 80% methanolic extract of the seeds of Abrus precatorius (Linn). It was characterised as a new biologically active flavonol glycoside 7,3',5'-trimethoxy-4'-hydroxy flavone-3- O - g - d -galactosyl-(1 M 4)- f -

R. N. Yadava; V. Madhu Sudhan Reddy

2002-01-01

222

Free and Glycosidically Bound Volatiles of Mentha longifolia Growing in Croatia  

Microsoft Academic Search

The glycosides of volatile compounds and the essential oil were isolated from wild Mentha longifolia. After the enzymatic hydrolysis of glycosides, fourteen volatile aglycones were identified by GC\\/MS. The main aglycones were eugenol, 2-phenylethanol, benzyl alcohol, lavandulol, trans- and cis-carveol, 3-octanol, and 3-hexen-1-ol. The content of aglycones was 40.85 mg kg-1 of dried plant material. The main components of the

J. Mastelic; I. Jerkovic

2002-01-01

223

Cyanogenic glycosides content in two edible leaves of tree spinach ( Cnidoscolus spp.)  

Microsoft Academic Search

The cyanogenic glycosides content (ranging from 0.79±0.2 to 14.79±0.4?g HCN equivalent\\/g fresh wt) of two edible tree spinach (Cnidoscolus chayamansa McVaugh and C. aconitifolius (P. Mill.) I.M. Johnston) leaves was quantitatively analyzed using enzymatic assay and UV-vis spectrum techniques. Both techniques equally show efficiency and reliability in assessing cyanogen content in tree spinach vegetable tissues. Cyanogenic glycoside concentration was significantly

Joseph O. Kuti; Hima B. Konoru

2006-01-01

224

Deglycosylation of flavonoid and isoflavonoid glycosides by human small intestine and liver ?-glucosidase activity  

Microsoft Academic Search

Flavonoid and isoflavonoid glycosides are common dietary phenolics which may be absorbed from the small intestine of humans. The ability of cell-free extracts from human small intestine and liver to deglycosylate various (iso)flavonoid glycosides was investigated. Quercetin 4?-glucoside, naringenin 7-glucoside, apigenin 7-glucoside, genistein 7-glucoside and daidzein 7-glucoside were rapidly deglycosylated by both tissue extracts, whereas quercetin 3,4?-diglucoside, quercetin 3-glucoside, kaempferol

Andrea J Day; M. Susan DuPont; Saxon Ridley; Mike Rhodes; Michael J. C Rhodes; Michael R. A Morgan; Gary Williamson

1998-01-01

225

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

PubMed

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 their dry weight. Eight different iridoid glycosides, acetylharpagide, ajugol, aucubin, catalpol, 8-epi-loganic acid, gardoside, geniposidic acid, and harpagide could be identified in the host plants, yet only aucubin and catalpol are sequestered by the beetles. No iridoid glycosides could be detected in the beetles if neither aucubin nor catalpol were present in the host plant, as in L. minusculus on Stachys recta (acetylharpagide only) and in L. salviae on Salvia pratensis (no iridoid glycosides). In one beetle species, L. luridus, we could not detect any iridoid glycosides although its field host, Plantago lanceolata, had considerable amounts of aucubin and catalpol plus two further iridoids. The five sequestering Longitarsus species differ in their capacity to store the compounds and in their affinity for catalpol relative to aucubin. PMID:11182483

Willinger, G; Dobler, S

2001-04-01

226

Comparison of three thermostable ?-glucosidases for application in the hydrolysis of soybean isoflavone glycosides.  

PubMed

A novel thermostable ?-glucosidase (Te-BglA) from Thermoanaerobacter ethanolicus JW200 was cloned, characterized and compared for its activity against isoflavone glycosides with two ?-glucosidases (Tm-BglA, Tm-BglB) from Thermotoga maritima. Te-BglA exhibited maximum hydrolytic activity toward pNP-?-d-glucopyranoside (pNPG) at 80 °C and pH 7.0, was stable for a pH range of 4.6-7.8 and at 65 °C for 3 h, and had the lowest K(m) for the natural glycoside salicin and the highest relative substrate specificity (k(cat)/K(m))((salicin))/(k(cat)/K(m))((pNPG)) among the three enzymes. It converted isoflavone glycosides, including malonyl glycosides, in soybean flour to their aglycons more efficiently than Tm-BglA and Tm-BglB. After 3 h of incubation at 65 °C, Te-BglA produced complete hydrolysis of four isoflavone glycosides (namely, daidzin, genistin and their malonylated forms), exhibiting higher productivity of genistein and daidzein than the other two ?-glucosidases. Our results suggest that Te-BglA is preferable to Tm-BglA and Tm-BglB, but all three enzymes have great potential applications in converting isoflavone glycosides into their aglycons. PMID:21294581

Song, Xiangfei; Xue, Yemin; Wang, Qilei; Wu, Xixi

2011-03-01

227

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, ?ukasz; Marsza?ek, Krystian; Sk?pska, Sylwia

2014-11-19

228

CHARMM Additive All-Atom Force Field for Glycosidic Linkages between Hexopyranoses.  

PubMed

We present an extension of the CHARMM hexopyranose monosaccharide additive all-atom force field to enable modeling of glycosidic-linked hexopyranose polysaccharides. The new force field parameters encompass 1?1, 1?2, 1?3, 1?4, and 1?6 hexopyranose glycosidic linkages, as well as O-methylation at the C(1) anomeric carbon, and are developed to be consistent with the CHARMM all-atom biomolecular force fields for proteins, nucleic acids, and lipids. The parameters are developed in a hierarchical fashion using model compounds containing the key atoms in the full carbohydrates, in particular O-methyl-tetrahydropyran and glycosidic-linked dimers consisting of two molecules of tetrahyropyran or one of tetrahydropyran and one of cyclohexane. Target data for parameter optimization include full two-dimensional energy surfaces defined by the ?/? glycosidic dihedral angles in the disaccharide analogs as determined by quantum mechanical MP2/cc-pVTZ single point energies on MP2/6-31G(d) optimized structures (MP2/cc-pVTZ//MP2/6-31G(d)). In order to achieve balanced, transferable dihedral parameters for the ?/? glycosidic dihedral angles, surfaces for all possible chiralities at the ring carbon atoms involved in the glycosidic linkages are considered, resulting in over 5000 MP2/cc-pVTZ//MP2/6-31G(d) conformational energies. Also included as target data are vibrational frequencies, pair interaction energies and distances with water molecules, and intramolecular geometries including distortion of the glycosidic valence angle as a function of the glycosidic dihedral angles. The model-compound optimized force field parameters are validated on full disaccharides through comparison of molecular dynamics results to available experimental data. Good agreement is achieved with experiment for a variety of properties including crystal cell parameters and intramolecular geometries, aqueous densities, and aqueous NMR coupling constants associated with the glycosidic linkage. The newly-developed parameters allow for the modeling of linear, branched, and cyclic hexopyranose glycosides both alone and in heterogenous systems including proteins, nucleic acids and/or lipids when combined with existing CHARMM biomolecular force fields. PMID:20161005

Guvench, Olgun; Hatcher, Elizabeth R; Venable, Richard M; Pastor, Richard W; Mackerell, Alexander D

2009-08-20

229

A simple determination of steroidal alkaloid glycosides by thin-layer chromatography immunostaining using monoclonal antibody against solamargine  

Microsoft Academic Search

A method of determination for solasodine glycosides by using thin-layer chromatography (TLC) immunostaining was investigated. Solasodine glycosides separated by silica gel TLC were transferred to a polyvinylidene difluoride membrane. The membrane was treated with sodium periodate solution followed by bovine serum albumin (BSA), resulting in a solasodine glycoside-BSA conjugate. Conjugation was confirmed by matrix-assisted laser desorption\\/ionization mass spectrometry. Individual spots

Hiroyuki Tanaka; Waraporn Putalun; Chiyumi Tsuzaki; Yukihiro Shoyama

1997-01-01

230

Antioxidative iridoid glycosides from the sky flower (Duranta repens Linn).  

PubMed

Phytochemical investigations were performed on the EtOAc-soluble fraction of the whole plant of the sky flower (Duranta repens) which led to the isolation of the iridoid glycosides 1-6. Their structures were elucidated by both 1D and 2D NMR spectroscopic analysis. All the compounds showed potent antioxidative scavenging activity in four different tests, with half maximal inhibitory concentration (IC(50)) values in the range 0.481-0.719 mM against DPPH radicals, 4.07-17.21 ?M for the hydroxyl radical (·OH) inhibitory activity test, 43.3-97.37 ?M in the total reactive oxygen species (ROS) inhibitory activity test, and 3.39-18.94 ?M in the peroxynitrite (ONOO(-)) scavenging activity test. Duranterectoside A (1) displayed the strongest scavenging potential with IC(50) values of (0.481 ± 0.06 mM, 4.07 ± 0.03, 43.30 ± 0.05, 3.39 ± 0.02 ?M) for the DPPH radicals, ·OH inhibitory activity test, total ROS inhibitory activity test and the ONOO(-) scavenging activity test, respectively. PMID:21299433

Ijaz, Fozia; Ul Haq, Azhar; Ahmad, Ijaz; Ahmad, Nisar; Hussain, Javid; Chen, Sibao

2011-02-01

231

Cytotoxicity of cardenolides and cardenolide glycosides from Asclepias curassavica.  

PubMed

A new cardenolide, 12beta,14beta-dihydroxy-3beta,19-epoxy-3alpha-methoxy-5alpha-card-20(22)-enolide (6), and a new doubly linked cardenolide glycoside, 12beta-hydroxycalotropin (13), together with eleven known compounds, coroglaucigenin (1), 12beta-hydroxycoroglaucigenin (2), calotropagenin (3), desglucouzarin (4), 6'-O-feruloyl-desglucouzarin (5), calotropin (7), uscharidin (8), asclepin (9), 16alpha-hydroxyasclepin (10), 16alpha-acetoxycalotropin (11), and 16alpha-acetoxyasclepin (12), were isolated from the aerial part of ornamental milkweed, Asclepias curassavica and chemically elucidated through spectral analyses. All the isolates were evaluated for their cytotoxic activity against HepG2 and Raji cell lines. The results showed that asclepin (9) had the strongest cytotoxic activity with an IC(50) value of 0.02 microM against the two cancer cell lines and the new compound 13 had significant cytotoxic activity with IC(50) values of 0.69 and 1.46 microM, respectively. PMID:19251412

Li, Jun-Zhu; Qing, Chen; Chen, Chang-Xiang; Hao, Xiao-Jiang; Liu, Hai-Yang

2009-04-01

232

Thermus thermophilus Glycoside Hydrolase Family 57 Branching Enzyme  

PubMed Central

Branching enzyme (EC 2.4.1.18; glycogen branching enzyme; GBE) catalyzes the formation of ?1,6-branching points in glycogen. Until recently it was believed that all GBEs belong to glycoside hydrolase family 13 (GH13). Here we describe the cloning and expression of the Thermus thermophilus family GH57-type GBE and report its biochemical properties and crystal structure at 1.35-? resolution. The enzyme has a central (?/?)7-fold catalytic domain A with an inserted domain B between ?2 and ?5 and an ?-helix-rich C-terminal domain, which is shown to be essential for substrate binding and catalysis. A maltotriose was modeled in the active site of the enzyme which suggests that there is insufficient space for simultaneously binding of donor and acceptor substrates, and that the donor substrate must be cleaved before acceptor substrate can bind. The biochemical assessment showed that the GH57 GBE possesses about 4% hydrolytic activity with amylose and in vitro forms a glucan product with a novel fine structure, demonstrating that the GH57 GBE is clearly different from the GH13 GBEs characterized to date. PMID:21097495

Palomo, Marta; Pijning, Tjaard; Booiman, Thijs; Dobruchowska, Justyna M.; van der Vlist, Jeroen; Kralj, Slavko; Planas, Antoni; Loos, Katja; Kamerling, Johannis P.; Dijkstra, Bauke W.; van der Maarel, Marc J. E. C.; Dijkhuizen, Lubbert; Leemhuis, Hans

2011-01-01

233

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

234

Host dependent iridoid glycoside sequestration patterns in Cionus hortulanus.  

PubMed

Weevils of the genus Cionus (Curculionidae, Mecininae) sequester the iridoid glycosides (IGs) aucubin and catalpol from their host plants Scrophularia or Verbascum (Scrophulariaceae). Cionus hortulanus is the only member of the genus that feeds on both plant genera. We previously showed that sequestration patterns in C. hortulanus depend on the local host. To investigate whether IG patterns are driven by their availability in the hosts or genetic differences between populations, we collected C. hortulanus from S. nodosa in the field and reared them either on S. nodosa or on V. nigrum. The differences in IG concentrations were specific for the host plant upon which the weevils developed. Similar to monophagous species of the Cionini, individuals from S. nodosa had more aucubin than catalpol and mirrored the concentrations of their host plants. Specimens from V. nigrum, on the other hand, had higher concentrations of aucubin and of catalpol than their host. On V. nigrum, the ratio of catalpol to aucubin differed significantly between plant and beetle samples due to much higher catalpol concentrations in the weevils. Our data thus contradict genetically fixed differences between populations living on either plant but rather document the host plants' influence on the beetles' metabolism. PMID:23846185

Baden, Christian Ulrich; Franke, Stephan; Dobler, Susanne

2013-08-01

235

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

236

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

237

Identification of flavone aglycones and glycosides in soybean pods by liquid chromatography-tandem mass spectrometry.  

PubMed

High-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry was used to identify flavone aglycones and glycosides in soybean pods. Tandem mass spectrometry (MS-MS and MS-MS-MS) and photodiode array detection were also utilized in flavone characterization. A total of seven flavone aglycones and glycosides were identified. Among them three flavone aglycones--apigenin, 7,4'-dihydroxyflavone, and luteolin--and two flavone glycosides--apigenin-7-O-beta-D-glucoside, and luteolin-7-O-beta-D-glucoside--were unambiguously identified based on their abundant (M+H)+ ions, UV spectra, retention time, and tandem mass spectrometric analysis compared with authentic standards. The tentative identification of two flavone glycosides as 7,4'-dihydroxyflavone-7-O-beta-D-glucoside and apigenin-7-O-beta-D-glucoside-6"-O-malonate was based on UV spectra, (M+H)+ ions, and tandem mass spectrometry. This is the first report identifying flavone aglycones and glycosides in soybean pods. PMID:12703901

Boué, Stephen M; Carter-Wientjes, Carol H; Shih, Betty Y; Cleveland, Thomas E

2003-03-28

238

Gold-catalyzed glycosidation for the synthesis of trisaccharides by applying the armed-disarmed strategy.  

PubMed

The synthesis of oligosaccharides is still a challenging task as there is no universal glycosyl donor for the synthesis of all oligosaccharides. The gold catalysis for glycosidation reactions, in which alkynylated glycosides are used, has emerged as one of the versatile options in this regard. A cleavage of the interglycosidic bond that was thought to be due to the higher reaction temperature and the acidic medium was observed during the synthesis of trisaccharides. In addition, a very little percentage of deprotection of benzyl protecting groups at the C-6 position was observed and no deprotection of benzyl ethers in aliphatic molecules was noticed. In order to overcome this fact, a collection of leaving groups that contain an alkynyl moiety were screened. It was found that 1-ethynylcyclohexanyl (Ech) glycosides are suitable for carrying out the glycosidation at 25 °C in the presence of 5 mol % each of AuCl3 and AgSbF6. Subsequently, Ech-glycosides were observed to be suitable for the synthesis of trisaccharides under gold catalysis conditions. PMID:24204427

Kayastha, Abhijeet K; Hotha, Srinivas

2013-01-01

239

Gold-catalyzed glycosidation for the synthesis of trisaccharides by applying the armed–disarmed strategy  

PubMed Central

Summary The synthesis of oligosaccharides is still a challenging task as there is no universal glycosyl donor for the synthesis of all oligosaccharides. The gold catalysis for glycosidation reactions, in which alkynylated glycosides are used, has emerged as one of the versatile options in this regard. A cleavage of the interglycosidic bond that was thought to be due to the higher reaction temperature and the acidic medium was observed during the synthesis of trisaccharides. In addition, a very little percentage of deprotection of benzyl protecting groups at the C-6 position was observed and no deprotection of benzyl ethers in aliphatic molecules was noticed. In order to overcome this fact, a collection of leaving groups that contain an alkynyl moiety were screened. It was found that 1-ethynylcyclohexanyl (Ech) glycosides are suitable for carrying out the glycosidation at 25 °C in the presence of 5 mol % each of AuCl3 and AgSbF6. Subsequently, Ech-glycosides were observed to be suitable for the synthesis of trisaccharides under gold catalysis conditions. PMID:24204427

Kayastha, Abhijeet K

2013-01-01

240

Two new anti-plasmodial flavonoid glycosides from Duranta repens.  

PubMed

The CHCl(3)-soluble fraction of the whole plant of Duranta repens showed anti-plasmodial activity against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum, with IC(50) values of 8.5?±?0.9 and 10.2?±?1.5??g/mL, respectively. From this fraction, two new flavonoid glycosides, 7-O-?-d-glucopyranosyl-3,4'-dihydroxy-3'-(4-hydroxy-3-methylbutyl)-5,6-dimethoxyflavone (1) and 7-O-?-d-glucopyranosyl(6'''-p-hydroxcinnamoyl)-3,4'-dihydroxy-3'-(4-hydroxy-3-methylbutyl)-5,6-dimethoxyflavone (2), along with five known flavonoids, 3,7,4'-trihydroxy-3'-(4-hydroxy-3-methylbutyl)-5,6-dimethoxyflavone (3), 3,7-dihydroxy-3'-(4-hydroxy-3-methylbutyl)-5,6,4'-trimethoxyflavone (4), 5,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-3,6,4'-trimethoxyflavone (5), 3,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-buten-yl)-5,6,4'-trimethoxyflavone (6), and 7-O-?-d-glucopyranosyl-3,5-dihydroxy-3'-(4''-acetoxy-3''-methylbutyl)-6,4'-dimethoxyflavone (7), have been isolated as anti-plasmodial principles. Their structures were deduced by spectroscopic analysis including 1D and 2D NMR techniques. The compounds (1-7) showed potent anti-plasmodial activities against D6 and W2 strains of Plasmodium falciparum, with IC(50) values in the range of 5.2-13.5??M and 5.9-13.1??M, respectively. PMID:20565340

Ijaz, Fozia; Ahmad, Nisar; Ahmad, Ijaz; ul Haq, Azhar; Wang, Fanghai

2010-12-01

241

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

242

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

243

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

244

[Flavonol glycosides of apples (Malus silvestris Mill.). 10. Phenolics of fruits (author's transl)].  

PubMed

The flavonol glycosides of apple skin (Malus silvestris Mill. cv. Golden Delicious) were separated by means of cellulose column chromatography and paper chromatography, and the following compounds were obtained crystalline and identified by usual procedures: quercetin 3-O-alpha-D-galactoside, quercetin 3-O-xyloside, quercetin 3-O-alpha-L-arabinofuranoside, quercetin 3-O-rhamnoside and rutin. Quercetin 3-O-beta-D-glucoside also was identified, but could not be obtained crystallin. A comparison by TLC of 10 very different varieties of apples namely Golden Delicious, Cox Orange, Roter Berlepsch, Cortland, Ingrid Marie, Jonathan, Boskoop, Laxtons Superb, Gloster, and James Grieve demonstrated the same flavonol glycosides and thus showed no distinctions in glycosid pattern between the different varieties of these apples. PMID:636663

Teuber, H; Herrmann, K

1978-02-24

245

Organosolv pretreatment of Sitka spruce wood: conversion of hemicelluloses to ethyl glycosides.  

PubMed

A range of Organosolv pretreatments, using ethanol:water mixtures with dilute sulphuric acid, were applied to Sitka spruce sawdust with the aim of generating useful co-products as well as improving saccharification yield. The most efficient of the pretreatment conditions, resulting in subsequent saccharification yields of up to 86%, converted a large part of the hemicellulose sugars to their ethyl glycosides as identified by GC/MS. These conditions also reduced conversion of pentoses to furfural, the ethyl glycosides being more stable to dehydration than the parent pentoses. Through comparison with the behaviour of model compounds under the same reaction conditions it was shown that the anomeric composition of the products was consistent with a predominant transglycosylation reaction mechanism, rather than hydrolysis followed by glycosylation. The ethyl glycosides have potential as intermediates in the sustainable production of high-value chemicals. PMID:24269088

Bouxin, Florent P; David Jackson, S; Jarvis, Michael C

2014-01-01

246

Inhibition of free radical initiated peroxidation of human erythrocyte ghosts by flavonols and their glycosides.  

PubMed

The in vitro peroxidation of human erythrocyte ghosts was used as a model to study the free radical-induced damage of biological membranes and the protective effect of flavonols and their glycosides, i.e., quercetin (Q), quercetin galactopyranoside (QG), quercetin rhamnopyranoside (QR), rutin (R), morin (MO), kaempferol (K) and kaempferol glucoside (KG). The peroxidation was initiated by a water-soluble free radical initiator 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AMPAD) at physiological temperature, and monitored by oxygen uptake. Kinetic analysis of the peroxidation process demonstrates that these flavonols and their glycosides are effective antioxidants against AMPAD-initiated oxidative damage of human erythrocyte ghosts, and that the flavonols bearing ortho-dihydroxyl groups possess significantly higher antioxidant activity than those bearing no such functionalities and the glycosides are less active than their parent aglycones. PMID:15105935

Hou, Lifen; Zhou, Bo; Yang, Li; Liu, Zhong-Li

2004-05-01

247

Inhibition of human low density lipoprotein oxidation by flavonols and their glycosides.  

PubMed

Antioxidative effects of the flavonols and their glycosides, i.e., quercetin (Q), quercetin galactopyranoside (QG), quercetin rhamnolpyranoside (QR), rutin (R), morin (MO), myrecetin (MY), kaempferol (K) and kaempferol glucoside (KG), against free radical initiated peroxidation of human low density lipoprotein (LDL) were studied. The peroxidation was initiated either by a water-soluble initiator 2,2'-azobis(2-amidino propane hydrochloride) (AAPH), or by cupric ion (Cu2+). The reaction kinetics were monitored either by the uptake of oxygen and the depletion of alpha-tocopherol (TOH) presented in the native LDL, or by the formation of thiobarbituric acid reactive substances (TBARS). Kinetic analysis of the antioxidation process demonstrates that these flavonols and their glycosides are effective antioxidants against AAPH- and Cu(2+)-initiated LDL peroxidation, the flavonols bearing ortho-dihydroxyl groups possess significantly higher antioxidant activity than those bearing no such functionalities, and the glycosides are less active than their parent aglycones. PMID:15081861

Hou, Lifen; Zhou, Bo; Yang, Li; Liu, Zhong-Li

2004-05-01

248

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

249

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

250

Two new bioactive triterpene glycosides from the sea cucumber Pseudocolochirus violaceus.  

PubMed

By activity-guided fractionation, two new triterpene glycosides, violaceusides A (1) and B (2), were isolated from the sea cucumber Pseudocolochirus violaceus as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. By extensive 2D NMR techniques and chemical evidence, the structures of the two new glycosides were established as 16beta-acetoxy-3-O-[3-O-methyl-beta-D-glucopyranosyl-(1 --> 3)-beta-D-xylopyranosyl-(1 --> 4)-beta-D-quinovopyranosyl-(1 --> 2)-4-O-sodiumsulphate-beta-D-xylopyranosyl]-holosta-7,24-diene-3beta-ol (1) and 16beta-acetoxy-3-O-[3-O-methyl-beta-D-glucopyranosyl-(1 --> 3)-beta-D-xylopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 2)-4-O-sodiumsulphate-beta-D-xylopyranosyl]-holosta-7,24-diene-3beta-ol (2), respectively. The two glycosides also exhibited significant cytotoxicity against HL-60 and BEL-7402 cancer cell lines. PMID:16753775

Zhang, Shu-Yu; Yi, Yang-Hua; Tang, Hai-Feng; Li, Ling; Sun, Peng; Wu, Jun

2006-01-01

251

Two new quinochalcone C-glycosides from the florets of Carthamus tinctorius.  

PubMed

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

252

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

PubMed Central

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.; Koeppen, B. H.

1965-01-01

253

Leaf variation in iridoid glycoside content of Plantago lanceolata (Plantaginaceae) and oviposition of the buckeye, Junonia coenia (Nymphalidae)  

Microsoft Academic Search

Summary Chemical analysis of each individual leaf of fivePlantago lanceolata (Plantaginaceae) plants showed that iridoid glycoside content increased from undetectable in the oldest photosynthetic leaves to over 9% dry weight in the youngest leaves. The relative proportion of the two iridoid glycosides inP. lanceolata also changed with leaf age: older leaves had significantly more aucubin, whereas the youngest leaves had

Gretchen K. Klockars; M. Deane Bowers; Barbara Cooney

1993-01-01

254

Antioxidant efficacy of iridoid and phenylethanoid glycosides from the medicinal plant Teucrium chamaedris in cell-free systems  

Microsoft Academic Search

Twelve glycosides, seven iridoids and five phenylethanoids, have been isolated from leaf and root methanolic extracts of Wall Germander (Teucrium chamaedrys), a Mediterranean species historically used as a medicinal plant. Among them, three iridoid and one phenylethanoid glycosides have been isolated and characterized for the first time. All of the structures have been elucidated on the basis of their spectral

Severina Pacifico; Brigida D’Abrosca; Maria Teresa Pascarella; Marianna Letizia; Piera Uzzo; Vincenzo Piscopo; Antonio Fiorentino

2009-01-01

255

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.; Hernández-Gay, José Juan; Cañada, F. Javier; Jiménez-Barbero, Jesús; Mootoo, David R.

2007-01-01

256

Synthesis of phenylazonaphtol-?-D-O-glycosides, evaluation as substrates for beta-glycosidase activity and molecular studies  

PubMed Central

Background Phenylazonaphtol-?-D-O-glycosides are alternative substrates for the detection of enzymatic activity of ?-glycosidases which are involved in various important processes. These azoic compounds are currently exploited as prodrugs for colonic disease due the presence of ?-glycosidase activity in the gut flora and therefore allowing the release of the drug at the specific site. Results Phenylazonaphtol-?-D-O-glucoside 3a and galactoside 3b were prepared via diazonium salt conditions under weak acidic conditions which do not compromise the O-glycosidic bond stability, by coupling reaction between 2-naphtol sodium salt with aminoglycosides 1a and 1b. The resulting phenylazonaphtol glycosides 2a and 2b were deprotected affording the phenylazonaphtol glycosides 3a and 3b in quantitative yield. The galactoside glycoside 3b was assayed as substrate for in vitro ?-galactosidase enzymatic activity showing strong absorbance after releasing of the azoic chromophore. Also, docking studies were performed to determine the best pose as well as the interactions between the ligand and the residues located at the active site. Conclusions The methodology developed for synthesizing the phenylazonaphtol glycosides described proved to be convenient for generating azoic functionalities in the presence of glycosidic bonds and the glycosides suitable as alternative substrates and potentially useful prodrugs in the treatment of colonic diseases. PMID:24995152

2014-01-01

257

Synthesis of C-2 methylene glycosides from C-2 propargyloxymethyl glycals exploiting the alkynophilicity of AuCl 3  

Microsoft Academic Search

C-2 Methylene glycosides were synthesized from C-2 propargyloxymethyl glycals in a stereoselective manner using a catalytic quantity of AuCl3. The Au-catalyzed reaction was explored using various aglycones. The current protocol enables the preparation of C-2 methylene glycosides, tolerates diverse functional groups and is fast, catalytic and mild.

Sudhir Kashyap; Srinivasa Rao Vidadala; Srinivas Hotha

2007-01-01

258

Differential EI Fragmentation Pathways for Peracetylated C-Glycoside Ketones as a Consequence of Bicyclic Ketal Ring Structures  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several C-glycoside ketones and peracetylated C-glycoside ketones have been synthesized from 13 structurally-diverse aldoses sugars (including isotope labeled [1-**13C]Glc, [U-**13C]Glc, and [6,6’-**2H2]Glc) via an aqueous-based Knoevanagel condensation with aliphatic 1,3-diketones. Sodium adduct m...

259

Angiotensin-converting enzyme inhibitory and antioxidant activities of enzymatically synthesized phenolic and vitamin glycosides.  

PubMed

Amyloglucosidase from Rhizopus mould and beta-glucosidase from sweet almond were employed for the preparation of phenolic and vitamin glycosides of vanillin, N-vanillylnonanamide, DL-dopa, dopamine, curcumin, alpha-tocopherol (vitamin E), pyridoxine (vitamin B(6)), ergocalciferol (vitamin D(2)), thiamin (vitamin B(1)) and riboflavin (vitamin B(2)). Approx. 20 enzymatically prepared phenolic and vitamin glycosides were subjected to ACE (angiotensin-converting enzyme) inhibition activity measurements, and 14 glycosides were tested for antioxidant activities. Both phenolic and vitamin glycosides exhibited IC(50) values for ACE inhibition in the 0.52+/-0.03-3.33+/-0.17 mM range and antioxidant activities ranging from 0.8+/-0.04 to 1.18+/-0.06 mM. Comparable ACE inhibition values were observed between free phenols and vitamin glycosides. However, antioxidant activities of glycosides were, in general, lesser than those of free phenols. Best IC(50) value for ACE inhibition were observed for 11-O-(D-fructofuranosyl)thiamin (0.52+/-0.03 mM), 3-hydroxy-4-O-(6-D-sorbitol)phenylalanine (0.56+/-0.03 mM), 4-O-(beta-D-glucopyranosyl)vanillin (0.61+/-0.03 mM), 4-O-(D-galactopyranosyl)vanillin (0.61+/-0.03 mM) and pyridoxine-D-glucoside (0.84+/-0.04 mM). Similarly, best IC(50) values for antioxidant activity were observed for 1,7-O-(bis-beta-D-glucopyranosyl)curcumin (0.8+/-0.04 mM), 4-O-(beta-D-glucopyranosyl)vanillin (0.9+/-0.05 mM), 3-hydroxy-4-O-(beta-D-galactopyranosyl-(1'-->4)beta-D-glucopyranosyl)phenylalanine (0.9+/-0.05 mM), 20-O-(D-glucopyranosyl)ergocalciferol (0.9+/-0.05 mM) and dopamine-D-galactoside (0.93+/-0.05 mM). PMID:18547170

Charles, Rajachristu Einstein; Ponrasu, Thangavel; Sivakumar, Ramaiah; Divakar, Soundar

2009-03-01

260

Triterpene and steroidal glycosides from the genus Melilotus and their genins  

Microsoft Academic Search

Three new triterpene oleanane glycosides, melilotosides A1, B1, and C1, and non-glycosylated soyasapogenol B were isolated from Melilotus officinalis (L.) Pall. (Fabaceae) roots. The structures\\u000a of the glycosides were proved using chemical transformations and spectral data. Melilotoside A1 is soyasapogenol B 3-O-?-Dxylopyranoside; melilotoside B1, soyasapogenol B 3-O-[?-D-galactopyranosyl-(1-2)-f-D-xylopyranoside]; melilotoside C1, soyasapogenol B 3-O-[?-L-rhamnopyranosyl-(1-2)-?-D-galactopyranosyl(1-2)-?-Dxylopyranoside].

G. V. Khodakov

2010-01-01

261

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

262

Potential anti-inflammatory phenolic glycosides from the medicinal plant Moringa oleifera fruits  

Microsoft Academic Search

Bioassay-guided isolation and purification of the ethyl acetate extract of Moringa oleifera fruits yielded three new phenolic glycosides; 4-[(2?-O-acetyl-?-l-rhamnosyloxy) benzyl]isothiocyanate (1), 4-[(3?-O-acetyl-?-l-rhamnosyloxy)benzyl]isothiocyanate (2), and S-methyl-N-{4-[(?-l-rhamnosyloxy)benzyl]}thiocarbamate (3), together with five known phenolic glycosides (4–8). The structures of the new metabolites were determined on the basis of spectroscopic analyses including 1D- and 2D-NMR and mass spectrometry. The anti-inflammatory activity of isolated compounds

Sarot Cheenpracha; Eun-Jung Park; Wesley Y. Yoshida; Chaz Barit; Marisa Wall; John M. Pezzuto; Leng Chee Chang

2010-01-01

263

Flavone-di- C-glycosides in citrus juices from Southern Italy  

Microsoft Academic Search

6,8-Di-C-glucopyranosylapigenin and 6,8-di-C-glucopyranosyldiosmetin were detected by HPLC–DAD–ESI–MS–MS in a variety of Southern Italian Citrus juices (orange, lemon, bergamot, citron, mandarin, clementine). In some juices, the amounts of C-glycosides detected were significant. 6,8-Di-C-glucopyranosylapigenin is characteristic of orange juice, while 6,8-di-C-glucopyranosyldiosmetin is the most important C-glycoside in lemon and citron juice. In bergamot juice the concentrations of 6,8-di-C-glucopyranosylapigenin and 6,8-di-C-glucopyranosyldiosmetin are similar.

Corrado Caristi; Ersilia Bellocco; Claudia Gargiulli; Giovanni Toscano; Ugo Leuzzi

2006-01-01

264

Oplopanphesides A-C, three new phenolic glycosides from the root barks of Oplopanax horridus.  

PubMed

Three new phenolic glycosides, named oplopanphesides A-C (1-3), have been isolated from the root barks of Oplopanax horridus. Their structures were elucidated by a combination of spectroscopic analyses, including 1D- and 2D-NMR techniques. These phenolic glycosides possess a novel feature in their sugar moieties that a 3-hydroxy-3-methylglutaryl moiety was connected with C-6 of the ?-D-glucopyranosyl group. Those compounds showed no cytotoxic effects against human cancer cell lines (MDA-231 and MCF-7) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. PMID:21532210

Huang, Wei-Hua; Zhang, Qing-Wen; Meng, Lan-Zhen; Yuan, Chun-Su; Wang, Chong-Zhi; Li, Shao-Ping

2011-01-01

265

Stereoselective synthesis of ?-linked 2-deoxy glycosides enabled by visible-light-mediated reductive deiodination.  

PubMed

2-Deoxy sugars and their derivatives occur abundantly in many pharmaceutically important natural products. However, the construction of specific 2-deoxy-glycosidic bonds remains as a challenge. Herein, we report an efficient way to prepare 2-deoxy-?-glycosides by glycosylation of 2-iodo-glycosyl acetate and subsequent visible-light-mediated tin-free reductive deiodination. We have successfully applied the postglycosylational-deiodination strategy in the synthesis of more than 30 mono-, di-, tri-, tetra- and pentadeoxysaccharides with excellent stereoselectivity and efficiency. This method has also been applied to the synthesis of a 2-deoxy-tetrasaccharide containing four ?-linkages. PMID:25377922

Wang, Hao; Tao, Jinyi; Cai, Xinpei; Chen, Wei; Zhao, Yueqi; Xu, Yang; Yao, Wang; Zeng, Jing; Wan, Qian

2014-12-22

266

Microwave-assisted efficient synthesis of aryl ketone ?-C-glycosides from unprotected aldoses.  

PubMed

Condensation between unprotected aldoses and dibenzoylmethane catalyzed by NaHCO(3) in the cosolvents EtOH and H(2)O (4:1) under microwave irradiation gave aryl ketone ?-C-glycosides 6b-i in higher yields (from 50% with C-riboside 6g up to 99% with C-glucoside 6b) and better anomeric selectivities (?-configuration >95%) in a shorter reaction time (90 min), compared with previous conventional methodologies. This method provides an attractive alternative to the existing means for the preparation of high value ketone ?-C-glycosides. PMID:21185012

Feng, Weiwei; Fang, Zhijie; Yang, Jingmei; Zheng, Baohui; Jiang, Yuhua

2011-02-01

267

Cordifolide A, a Sulfur-containing Clerodane Diterpene Glycoside from Tinospora cordifolia  

PubMed Central

Cordifolide A (1), a novel unprecedented sulfur-containing clerodane diterpene glycoside, together with other two new diterpene glycosides, cordifolides B (2) and C (3), and four known analogues, was isolated from a methanol-soluble extract of the stems of Tinospora cordifolia. The structures of the new compounds were determined on the basis of spectroscopic data interpretation, with that of cordifolide A (1) confirmed by a single-crystal X-ray crystallographic analysis. All isolates were evaluated for their in vitro immunomodulatory activity using mouse bone marrow-derived dentritic cells (BMDCs). PMID:22497272

Pan, Li; Terrazas, Cesar; Lezama-Davila, Claudio M.; Rege, Nirmala; Gallucci, Judith C.; Satoskar, Abhay R.; Kinghorn, A. Douglas

2012-01-01

268

Pseudocnoside A, a new cytotoxic and antiproliferative triterpene glycoside from the sea cucumber Pseudocnus dubiosus leoninus.  

PubMed

A new triterpene glycoside, pseudocnoside A (1), was isolated from the sea cucumber Pseudocnus dubiosus leoninus. The structure of the new compound was established on the basis of extensive NMR spectroscopic analysis ((1)H and (13)C NMR, (1)H,(1)H-COSY, HMBC, HSQC, TOCSY and NOESY), HR-ESI-MS data and chemical transformations. In addition, the cytotoxicity and antiproliferative activities of 1 and structurally related triterpene glycosides isolated from the sea cucumbers Psolus patagonicus and Hemioedema spectabilis were evaluated against cancer cell lines A-549 and HeLa. PMID:23244698

Careaga, Valeria P; Bueno, Carlos; Muniain, Claudia; Alché, Laura; Maier, Marta S

2014-01-01

269

Novel indole C-glycosides from Isatis indigotica and their potential cytotoxic activity  

Microsoft Academic Search

Two novel indole C-glycosides, which were the first reported alkaloids C-glycosides from Isatis indigotica, together with five known alkaloids were isolated. The novel alkaloids were elucidated to be indole-3-acetonitrile-4-methoxy-2-C-?-D-glucopyranoside (1) and N-methoxy-indole-3-acetonitrile-2-C-?-D-glucopyranoside (2) on the basis of spectroscopic analysis. 1 exhibited significant cytotoxic activities against human myeloid leukemia HL-60 and human liver cancer HepG2 cells with the IC50 of 1.3±0.1

Yixuan Wu; Zhen-Xue Zhang; Hui Hu; Dongmei Li; Guofu Qiu; Xianming Hu; Xiangjiu He

2011-01-01

270

A new steroidal glycoside from the Ophiopogon japonicus Ker-Gawler (Liliaceae).  

PubMed

A new steroidal glycoside (1), (25R)-14?, 17?-hydroxyspirost-5-en-3?-yl 3-O-?-L-rhamnpyranosyl-(1 ? 2)-?-D-glucopyranosyl-(1 ? 3)-?-D-glucopyranoside, together with three known steroidal glycosides, (25R)-3?-hydroxyspirost-5-en-1?-yl-3-O-?-L-rhamnopyranosyl-(1 ? 2)-O-?-D-xylopyranosyl-(1 ? 3)-?-L-arabinopyranoside (2), Cixi-ophiopogon B (3) and Cixi-ophiopogon A (4), were obtained from the tuberous roots of Ophiopogon japonicus (Liliaceae). Compound 2 was isolated from the Ophiopogon genus for the first time. Their structures were identified on the basis of extensive mass and nuclear magnetic resonance spectroscopic analysis. PMID:21240758

Wang, Yongyi; Xu, Jinzhong; Zhang, Lei; Qu, Haibin

2011-01-01

271

Isolation and structure elucidation of new nitrile and mustard oil glycosides from Moringa oleifera and their effect on blood pressure.  

PubMed

Bioassay-guided analysis of an EtOH extract of Moringa oleifera leaves showing hypotensive activity led to the isolation of two nitrile glycosides, niazirin [1] and niazirinin [2], and three mustard oil glycosides, 4-[(4'-O-acetyl-alpha-L-rhamnosyloxy)benzyl]isothiocyanate [4], niaziminin A, and niaziminin B. Glycoside 2 is a new compound. Niaziminins A and B have previously been obtained from the left extract as a mixture, while compound 4 is new from this source. Structural determination was accomplished by means of spectroscopic methods including appropriate 2D nmr experiments and chemical reactions. This is the first report of the isolation of nitriles, an isothiocyanate, and thiocarbamates from the same plant species. Isothiocyanate 4 and the thiocarbamate glycosides niaziminin A and B showed hypotensive activity while nitrile glycosides 1 and 2 were found to be inactive in this regard. PMID:7798960

Faizi, S; Siddiqui, B S; Saleem, R; Siddiqui, S; Aftab, K; Gilani, A H

1994-09-01

272

Antioxidative and hypocholesterolemic activities of water-soluble puerarin glycosides in HepG2 cells and in C57 BL\\/6J mice  

Microsoft Academic Search

Puerarin is an isoflavone derived from Kudzu roots and has antioxidant and hypocholesterolemic effects; however, its insolubility often limits its biological availability in vivo. Using a novel transglycosylation process, the solubility of puerarin glycosides was increased >100-fold, but it was not known whether these modified puerarin glycosides maintained biological activities. We found that water-soluble puerarin glycosides fully maintained antioxidant activities

Mi Ja Chung; Nak-Ju Sung; Cheon-Seok Park; Dong-Keon Kweon; Alberto Mantovani; Tae-Wha Moon; Sung-Joon Lee; Kwan-Hwa Park

2008-01-01

273

Overview: The history, technical function and safety of rebaudioside A, a naturally occurring steviol glycoside, for use in food and beverages  

Microsoft Academic Search

Rebaudioside A is a sweet tasting steviol glycoside extracted and purified from Stevia rebaudiana (Bertoni). Steviol glycosides can currently be used as a food ingredient in only a handful of countries. Questions on specifications, safety and special population effects have prevented steviol glycosides from obtaining a legal status permitting their use as a sweetener in most countries. A set of

M. C. Carakostas; L. L. Curry; A. C. Boileau; D. J. Brusick

2008-01-01

274

Flavonoid glycoside variations in the progeny of wild specimens of Centaurea montana and comments on the origin of their natural diversity  

Microsoft Academic Search

From a series of wild accessions of Centaurea montana displaying markedly dissimilar flavonoid phenotypes (notably C-glycosides vs. O-glycosides) different experimental breeding operations were performed. Variation was observed in individual glycosidic profiles of progeny, the importance of which depended on the parental phenotypes and the genetic proximity of the partners employed (combinations of wild specimens, inbred, plants or backcrosses operations). Most

Jean-François Gonnet

1996-01-01

275

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

276

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

277

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

278

Highly active ß-xylosidases of glycoside hydrolase family 43 operating on natural and artificial substrates  

Technology Transfer Automated Retrieval System (TEKTRAN)

The hemicellulose xylan constitutes a major portion of plant biomass, a renewable feedstock available for conversion to biofuels and other bioproducts. ß-xylosidase operates in the deconstruction of the polysaccharide to fermentable sugars. Glycoside hydrolase family 43 has been identified as a so...

279

Versatile Synthesis and Mechanism of Activation of S-Benzoxazolyl (SBox) Glycosides  

PubMed Central

As a part of a program for developing new efficient procedures for stereoselective glycosylation, a range of S-benzoxazolyl (SBox) glycosides have been synthesized. The mechanistic aspects of the SBox moiety activation for glycosylation via a variety of conceptually different pathways in the presence of thiophilic, electrophilic, or metal-based promoters have been investigated. PMID:17676918

Kamat, Medha N.; Rath, Nigam P.; Demchenko, Alexei V.

2008-01-01

280

Degradation of cyanogenic glycosides by Lactobacillus plantarum strains from spontaneous cassava fermentation and other microorganisms  

Microsoft Academic Search

Strains of Lactobacillus plantarum, Leuconostoc mesenteroides, Candida tropicalis and Penicillium sclerotiorum were screened for 19 enzymatic activities using the commercial kit API zym (Bio Mérieux). This activity was compared to the ability of degrading the toxic cyanogenic glycosides amygdalin, linamarin, and linseed cyanogens (a mixture of linustatin and neolinustatin). Good correlation between the ?-glucosidase activity found in the API zym

Vicki Lei; Wisdom Kofi Asa Amoa-Awua; Leon Brimer

1999-01-01

281

Patterns of Iridoid Glycoside Production and Induction in Plantago lanceolata and the Importance of Plant Age  

Microsoft Academic Search

Induction of allelochemicals is one way that plants efficiently deploy defenses against herbivory. In two separate experiments we investigated the time course of this inductive response and the importance of the timing of herbivory for Plantago lanceolata (Plantaginaceae). We found a localized induced response of catalpol and the ratio of catalpol to total iridoid glycosides in damaged leaves that was

Alexander Fuchs; M. Deane Bowers

2004-01-01

282

An anti-inflammatory and anti-microbial flavone glycoside from flowers of Cleome viscosa  

PubMed Central

Background Natural products isolated from plant sources have been demonstrated as potential candidates against several ailments. The scientific investigations on the underlying principles of phytotherapy can pave way for the convergence of traditional medicines and modern science and technologies. Results Quercetin 3-O-(2??-acetyl)-glucoside obtained from ethyl acetate fraction of Cleome viscosa is studied against inflammatory of carrageenan-induced rat paw edema ( in vivo) and microbial activity on ( in vitro). The structure of the glycoside is confirmed by means of hydrogen-1 nuclear magnetic resonance spectroscopy, carbon nuclear magnetic resonance spectroscopy, attached proton test, and mass spectrum. The flavonoid glycoside showed significant anti-inflammatory activity of on carrageenan-induced rat paw edema ( in vivo) and anti-microbial activity ( in vitro) on Staphylococcus aureus (gram positive) and Escherichia coli (gram negative). The anti-inflammatory effect of the flavonoid glycoside may be due to the inhibition of prostaglandin synthesis. Selective toxicity with flavonoid glycoside towards the gram-positive bacteria was found on S. aureus. Conclusions The present study reveals the anti-inflammatory and antimicrobial activities of an isolated quercetin 3-O-(2??-acetyl)-glucoside from a natural source ( C. viscosa). PMID:22613049

2012-01-01

283

Rehabilitation of faulty kinetic determinations and misassigned glycoside hydrolase family of retaining mechanism ß-xylosidases  

Technology Transfer Automated Retrieval System (TEKTRAN)

We obtained Cx1 from a commercial supplier, whose catalog listed it as a ß-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...

284

Clerodane and Ent-kaurane Diterpene Glycosyl and Glycoside Derivatives from the Leaves of Casearia sylvestris  

Technology Transfer Automated Retrieval System (TEKTRAN)

Five new clerodane diterpene glycosides caseariasides A-E (1-4) and three new ent-kaurane diterpene glucosides sylvestrisides C-E (6-8) were isolated from the leaves of Casearia sylvestris. Their structures were determined on the basis of chemical and spectroscopic analyses....

285

A New ent-Labdane Diterpene Glycoside form the Leaves of Casearia sylvestris  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sylvestin (1), a new ent-labdane glycoside, was isolated from the leaves of Casearia sylvestris. The structure was determined on the basis of 1D and 2 D NMR and HR-ESI-MS analyses. The diterpenoid of ent-labdane type was isolated for the first time from C. sylvestris....

286

Potential anti-inflammatory phenolic glycosides from the medicinal plant Moringa oleifera fruits  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bioassay-guided isolation and purification of the ethyl acetate extract of Moringa oleifera fruits yielded three new phenolic glycosides; 4-[(2'-O-acetyl-a-L-rhamnosyloxy) benzyl]isothiocyanate (1), 4-[(3'-O-acetyl-a-L-rhamnosyloxy)benzyl]isothiocyanate (2), and S-methyl-N-{4-[(a-L-rhamnosyloxy)benz...

287

New oleanan-type triterpene and cincholic acid glycosides from Peruvian "Uña de Gato" (Uncaria tomentosa).  

PubMed

A new oleanan-type triterpene and three new cincholic acid glycosides were isolated from Peruvian "Una de Gato" (Cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis. PMID:15467250

Kitajima, Mariko; Hashimoto, Ken-Ichiro; Sandoval, Manuel; Aimi, Norio; Takayama, Hiromitsu

2004-10-01

288

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

E-print Network

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

Hazen, Terry

289

Theoretical Calculation of Electronic Circular Dichroism of a Hexahydroxydiphenoyl-Containing Flavanone Glycoside  

Technology Transfer Automated Retrieval System (TEKTRAN)

Time-dependent density functional theory (TDDFT) was employed for theoretical calculation of electronic circular dichroism (ECD) of a hexahydroxydiphenoyl (HHDP)-containing flavanone glycoside, mattucinol-7-O-[4'',6''-O-(aS)-hexahydroxydiphenoyl]-ß-d-glucopyranoside (2). It identified the roles of t...

290

IDENTIFICATION OF FLAVONE AGLYCONES AND GLYCOSIDES IN SOYBEAN PODS BY LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY  

Technology Transfer Automated Retrieval System (TEKTRAN)

High-performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (HPLC-APCI-MS) was used to identify flavone aglycones and glycosides in soybean pods. Tandem mass spectrometry (MS/MS and MS3) and photodiode array detection were also utilized in flavone characterizat...

291

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

292

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

293

Enzymatic synthesis of salicin glycosides through transglycosylation catalyzed by amylosucrases from Deinococcus geothermalis and Neisseria polysaccharea.  

PubMed

Amylosucrase (ASase, EC 2.4.1.4) is a member of family 13 of the glycoside hydrolases that catalyze the synthesis of an alpha-(1-->4)-linked glucan polymer from sucrose instead of an expensive activated sugar, such as ADP- or UDP-glucose. Transglycosylation reactions mediated by the ASases of Deinococcus geothermalis (DGAS) and Neisseria polysaccharea (NPAS) were applied to the synthesis of salicin glycosides with sucrose serving as the glucopyranosyl donor and salicin as the acceptor molecule. Two salicin glycoside transfer products were detected by TLC and HPLC analyses. The synthesis of salicin glycosides was very efficient with NPAS with a yield of over 90%. In contrast, DGAS specifically synthesized only one salicin transglycosylation product. The transglycosylation products were identified as alpha-d-glucopyranosyl-(1-->4)-salicin (glucosyl salicin) and alpha-D-glucopyranosyl-(1-->4)-alpha-D-glucopyranosyl-(1-->4)-salicin (maltosyl salicin) by NMR analysis. The ratio between donor and acceptor had a significant effect on the type of product that resulted from the transglycosylation reaction. With more acceptors present in the reaction, more glucosyl salicin and less maltosyl salicin were synthesized. PMID:19482267

Jung, Jong-Hyun; Seo, Dong-Ho; Ha, Suk-Jin; Song, Myoung-Chong; Cha, Jaeho; Yoo, Sang-Ho; Kim, Tae-Jip; Baek, Nam-In; Baik, Moo-Yeol; Park, Cheon-Seok

2009-09-01

294

Phenolic glycosides govern the food selection pattern of willow feeding leaf beetles  

Microsoft Academic Search

The relationship between the food selection of four leaf beetle species (Phratora vitellinae, Plagiodera versicolora, Lochmaea capreae, Galerucella lineola) and the phenolic glycosides of willow (Salix spp.) leaves was tested in laboratory food choice experiments. Four willow species native to the study area (Eastern Finland) and four introduced, cultivated willows were tested.

J. Tahvanainen; R. Julkunen-Tiitto; J. Kettunen

1985-01-01

295

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

296

Flavonol glycosides from Epimedium sagittatum and their neurite outgrowth activity on PC12h cells.  

PubMed

The MeOH extract of Epimedium sagittatum was found to show neurite outgrowth activity on cultured PC12h cells. Bioassay-guided fractionation of the MeOH extract yielded six prenylated flavonol glycosides, ikarisoside A (1), icarisid II (2), epimedoside A (3), icariin (4), epimedin B (5), and epimedokoreanoside-I (6) as the active ingredients. PMID:10985091

Kuroda, M; Mimaki, Y; Sashida, Y; Umegaki, E; Yamazaki, M; Chiba, K; Mohri, T; Kitahara, M; Yasuda, A; Naoi, N; Xu, Z W; Li, M R

2000-08-01

297

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

298

Supplementing with Non-Glycoside Hydrolase Proteins Enhances Enzymatic Deconstruction of Plant Biomass  

PubMed Central

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

299

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

300

Reversible logic for supercomputing  

Microsoft Academic Search

This paper is about making reversible logic a reality for supercomputing. Reversible logic offers a way to exceed certain basic limits on the performance of computers, yet a powerful case will have to be made to justify its substantial development expense. This paper explores the limits of current, irreversible logic for supercomputers, thus forming a threshold above which reversible logic

Erik P. DeBenedictis; Erik P

2005-01-01

301

Fatsioside A, a rare baccharane-type glycoside inhibiting the growth of glioma cells from the fruits of Fatsia japonica.  

PubMed

A novel baccharane-type triterpenoid glycoside named fatsioside A (1), together with ten oleanane glycosides, were isolated from the fruits of Fatsia japonica. The structure of fatsioside A was assigned as 3?,15?,18?-trihydroxy-18,19-secolupane-12,19-dione 3-O-?-D-glucopyranosyl-(1 ? 2)-?-D-glucopyranoside by extensive NMR and HRESIMS analyses. F. japonica is the third baccharane glycoside-containing species reported to date in the plant kingdom, while fatsioside A represents the first baccharane glycoside found in the Araliaceae family. Fatsioside A inhibited the growth of rat glioma C6 cells and human glioma U251 cells with IC50 values of 33.48 ± 2.01 µM and 77.58 ± 6.19 µM, respectively. Further investigation indicated that fatsioside A induced apoptosis and necrosis in glioma cells, and arrested the cell cycle at the G0/G1 phase. PMID:24549925

Yu, Siran; Ye, Xuewei; Xin, Wenxiu; Xu, Kangning; Lian, Xiao-Yuan; Zhang, Zhizhen

2014-03-01

302

A simple method of synthesis of triterpene glycosides similar to glycyrrhizic acid and their hepatoprotective activity in vitro  

Microsoft Academic Search

A simplified method of synthesis of triterpene 1,2-trans-glycosides was developed using the glycosylation of glycyrrhetic acid (GLA) and 18,19-dehydro-GLA by ?-pyranose peracetates\\u000a in the presence of SnCl4 and molecular sieves 4 Å. The synthesized glycosides exhibited hepatoprotective activity toward the human hepatoma HepG2\\u000a cell line on the model of alcohol hepatitis and decreased the level of TNF-[alpha] protein.

L. R. Mikhailova; L. A. Baltina Jr; R. M. Kondratenko; S. A. Nepogodiev; R. A. Field; O. Kunert; M. Ch. Yin

2009-01-01

303

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

304

Identification of the Catalytic Residues in Family 52 Glycoside Hydrolase, a  Xylosidase from Geobacillus stearothermophilus T-6  

Microsoft Academic Search

-D-Xylosidases (EC 3.2.1.37) are exo-type glycoside hy- drolases that hydrolyze short xylooligosaccharides to xylose units. The enzymatic hydrolysis of the glycosidic bond involves two carboxylic acid residues, and their identification, together with the stereochemistry of the reaction, provides crucial information on the catalytic mechanism. Two catalytic mutants of a -xylosidase from Geobacillus stearothermophilus T-6 were subjected to detailed kinetic analysis

Tsafrir Bravman; Valery Belakhov; Dmitry Solomon; Gil Shoham; Bernard Henrissat; Timor Baasov; Yuval Shoham

2003-01-01

305

Reversible logic for supercomputing.  

SciTech Connect

This paper is about making reversible logic a reality for supercomputing. Reversible logic offers a way to exceed certain basic limits on the performance of computers, yet a powerful case will have to be made to justify its substantial development expense. This paper explores the limits of current, irreversible logic for supercomputers, thus forming a threshold above which reversible logic is the only solution. Problems above this threshold are discussed, with the science and mitigation of global warming being discussed in detail. To further develop the idea of using reversible logic in supercomputing, a design for a 1 Zettaflops supercomputer as required for addressing global climate warming is presented. However, to create such a design requires deviations from the mainstream of both the software for climate simulation and research directions of reversible logic. These deviations provide direction on how to make reversible logic practical

DeBenedictis, Erik P.

2004-12-01

306

Reversible logic for supercomputing.  

SciTech Connect

This paper is about making reversible logic a reality for supercomputing. Reversible logic offers a way to exceed certain basic limits on the performance of computers, yet a powerful case will have to be made to justify its substantial development expense. This paper explores the limits of current, irreversible logic for supercomputers, thus forming a threshold above which reversible logic is the only solution. Problems above this threshold are discussed, with the science and mitigation of global warming being discussed in detail. To further develop the idea of using reversible logic in supercomputing, a design for a 1 Zettaflops supercomputer as required for addressing global climate warming is presented. However, to create such a design requires deviations from the mainstream of both the software for climate simulation and research directions of reversible logic. These deviations provide direction on how to make reversible logic practical.

DeBenedictis, Erik P.

2005-05-01

307

Flavonol glycosides from Montcalm dark red kidney bean: implications for the genetics of seed coat color in Phaseolus vulgaris L.  

PubMed

Three flavonol glycosides were isolated and identified from the commercial dark red kidney bean (Phaseolus vulgaris L.) cultivar Montcalm. In order of highest to lowest concentration these compounds were 3',4',5,7-tetrahydroxyflavonol 3-O-beta-D-glucopyranosyl (2-->1) O-beta-D-xylopyranoside (compound 1), quercetin 3-O-beta-D-glucopyranoside (compound 2), and kaempferol 3-O-beta-D-glucopyranoside (compound 3). Compound 1 is a flavonol glycoside that has not been reported before in P. vulgaris L. These three flavonol glycosides were yellow compounds that do not contribute to the garnet red color of Montcalm seed coats. Red-colored compounds which tested positive for proanthocyanidins are most likely responsible for the red seed coat color of Montcalm. Previous work on the chemistry of the compounds produced from the multi-allelic seed coat gene series C-C(r)()-c(u) indicated that neither anthocyanins nor flavonol glycosides were detected from seed coat extracts in the presence of the c(u)() locus. However, the seed coat color genotype of Montcalm is c(u) J g B v rk(d) and three flavonol glycosides were found. Technological advances such as modern HPLC analysis of seed coat extracts may allow for detection of small amounts of compounds which previously could not be seen using paper chromatography. Alternatively, the change of the Rk allele to rk(d) may allow for the synthesis of flavonol glycosides in the presence of c(u). PMID:10552769

Beninger, C W; Hosfield, G L

1999-10-01

308

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

309

The uptake of cardiac glycosides by intestinal smooth muscle of the guinea-pig in relation to digitalis receptors  

PubMed Central

1. The accumulation and release of 3H-digitoxin, 3H-digoxin and 3H-ouabain by isolated guinea-pig intestinal smooth muscle has been studied and compared with a pharmacological action due to inhibition of the sodium pump. 2. The uptake of labelled cardiac glycosides can be described by means of an exponential function. The t of uptake was similar for the three compounds and did not depend on the concentration. 3. Analysis of the curve relating the uptake of cardiac glycosides at equilibrium to the bath concentration enabled a non-saturable and a saturable binding site to be distinguished. 4. In contrast to the uptake observations, the onset of the pharmacological effect was dependent on the concentration, and furthermore the t½ for this effect was shorter. 5. The release of cardiac glycosides proceeded more slowly than the uptake. 6. The uptake of a labelled glycoside was reduced in the presence of another glycoside. The amount of displaceable glycoside was nearly equivalent to the capacity of the saturable binding site. 7. The significance of these results is discussed. PMID:5417857

Godfraind, T.; Lesne, M.

1970-01-01

310

Synthesis of quercetin glycosides and their melanogenesis stimulatory activity in B16 melanoma cells.  

PubMed

4'-O-?-d-Glucopyranosyl-quercetin-3-O-?-d-glucopyranosyl-(1?4)-?-d-glucopyra-noside (3) was isolated from Helminthostachys zeylanica root extract as a melanogenesis acceleration compound and was synthesized using rutin as the starting material. Related compounds were also synthesized to understand the structure-activity relationships in melanin biosynthesis. Melanogenesis activities of the glycosides were determined by measuring intracellular melanin content in B16 melanoma cells. Among the synthesized quercetin glycosides, quercetin-3-O-?-d-glucopyranoside (1), quercetin-3-O-?-d-glucopyranosyl-(1?4)-?-d-glucopyranoside (2), and 3 showed more potent intracellular melanogenesis acceleration activities than theophyline used as positive control in a dose-dependent manner with no cytotoxic effect. PMID:24433966

Yamauchi, Kosei; Mitsunaga, Tohru; Batubara, Irmanida

2014-02-01

311

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

312

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

313

A phytochemical screening procedure for sweet ent-kaurene glycosides in the genus Stevia.  

PubMed

Altogether, 110 species of the genus Stevia, comprising both herbarium and fresh leaf samples, were screened for the presence of sweet ent-kaurene glycosides, using a combination of tlc and hplc, followed by gc/ms. Stevioside and rebaudiosides A and C were detected in a Stevia rebaudiana herbarium specimen collected in Paraguay in 1919, and stevioside was observed as a constituent of a Stevia phlebophylla herbarium specimen collected in Mexico in 1889. Steviol glycosides were not detected in any of the other 108 Stevia species studied. The phytochemical results obtained in this study are correlated with those of preliminary organoleptic tests on the sweetness of these Stevia samples, and the chemotaxonomic implications of the present findings are discussed. PMID:6481357

Kinghorn, A D; Soejarto, D D; Nanayakkara, N P; Compadre, C M; Makapugay, H C; Hovanec-Brown, J M; Medon, P J; Kamath, S K

1984-01-01

314

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

315

Cardenolides and bufadienolide glycosides from Kalanchoe tubiflora and evaluation of cytotoxicity.  

PubMed

Two new cardenolides, kalantubolide A (1) and kalantubolide B (2), and two bufadienolide glycosides, kalantuboside A (3) and kalantuboside B (4), as well as eleven known compounds were isolated and characterized from the EtOH extract of Kalanchoe tubiflora. The structures of compounds were assigned based on 1D and 2D NMR spectroscopic analyses including HMQC, HMBC, and NOESY. Biological evaluation indicated that cardenolides (1-2) and bufadienolide glycosides (3-7) showed strong cytotoxicity against four human tumor cell lines (A549, Cal-27, A2058, and HL-60) with IC50 values ranging from 0.01 µM to 10.66 µM. Cardenolides (1-2) also displayed significant cytotoxicity toward HL-60 tumor cell line. In addition, compounds 3, 4, 5, 6, and 7 blocked the cell cycle in the G2/M-phase and induced apoptosis in HL-60 cells. PMID:23877916

Huang, Hui-Chi; Lin, Ming-Kuem; Yang, Hsin-Ling; Hseu, You-Cheng; Liaw, Chih-Chuang; Tseng, Yen-Hsueh; Tsuzuki, Minoru; Kuo, Yueh-Hsiung

2013-09-01

316

Identification of a novel glycoside, leptosin, as a chemical marker of manuka honey.  

PubMed

As a preliminary study, we have found that honey from manuka (Leptospermum scoparium) in New Zealand inhibits myeloperoxidase (MPO) activity. In this study, using a chromatographic technique, we isolated two active compounds for MPO-inhibition from manuka honey. One is methyl syringate (MSYR), and the other was identified as a novel glycoside of MSYR, methyl syringate 4-O-?-D-gentiobiose, which has been named "leptosin" after the genus Leptospermum . The amount of the glycoside ranged from 0.2 to 1.2 ?mol/g honey. Leptosin was only found in honeys from the Oceania region, and abundantly in manuka honey including jelly bush honey from Leptospermum polygalifolium in Australia. Therefore, leptosin may be a good chemical marker for manuka honey. Interestingly, the concentration of leptosin in manuka honey was positively correlated with the unique manuka factor (UMF) value, which is expressed as phenol equivalents of its bactericidal activity. PMID:22409307

Kato, Yoji; Umeda, Natsuki; Maeda, Asuna; Matsumoto, Daiki; Kitamoto, Noritoshi; Kikuzaki, Hiroe

2012-04-01

317

Intercedensides A-C, three new cytotoxic triterpene glycosides from the sea cucumber Mensamaria intercedens Lampert.  

PubMed

Three new triterpene glycosides, intercedensides A (1), B (2), and C (3), were isolated from the sea cucumber Mensamria intercedens Lampert, which is found in the South China Sea, and their structures have been elucidated by spectroscopic analysis (NMR and ESIMS) and chemical transformations. Intercedensides A (1) and C (3) have a conjugated double bond (22E,24-diene) in the side chain of the aglycon. Intercedenside B (2) has two beta-D-xylose and two sulfate groups in the carbohydrate chain. All three glycosides showed significant cytotoxicity against 10 human tumor cell lines with ED(50) in the range 0.6-4.0 microg/mL. Intercedenside A (1) exhibited significant in vivo antineoplastic activity against mouse Lewis lung cancer and mouse S180 sarcoma. On the basis of these initially promising results, intercedensides A-C merit further study as potential anticancer agents. PMID:12932123

Zou, Zheng-Rong; Yi, Yang-Hua; Wu, Hou-Ming; Wu, Jiu-Hong; Liaw, Chih-Chaung; Lee, Kuo-Hsiung

2003-08-01

318

Quantitative analysis of flavonol glycosides in Ginkgo biloba: a comparison of two analytical methods.  

PubMed

A comparison of testing methods for constituents of Ginkgo biloba was performed as part of the process for determining which of the many available analytical methods was most appropriate for inclusion in the American Herbal Pharmacopoeia (AHP). Three primary methods were reviewed: those adopted by the European Pharmacopoeia, the National Science Foundation-Institute for Nutraceutical Advancement (NSF-INA) and the United States Pharmacopeia. Methods were compared by evaluating sample preparation and hydrolysis, precision and methods of total flavonol glycoside calculation by two independent laboratories. The AHP adopted the method of NSF-INA for inclusion in the AHP monograph owing to observed superiority of this method in terms of precision, glycoside calculation, ease of sample preparation and chromatographic parameters. PMID:16454477

Gray, D E; Upton, R; Chandra, A; Porter, A; Harris, R K

2006-01-01

319

Novel indole C-glycosides from Isatis indigotica and their potential cytotoxic activity.  

PubMed

Two novel indole C-glycosides, which were the first reported alkaloids C-glycosides from Isatis indigotica, together with five known alkaloids were isolated. The novel alkaloids were elucidated to be indole-3-acetonitrile-4-methoxy-2-C-?-D-glucopyranoside (1) and N-methoxy-indole-3-acetonitrile-2-C-?-D-glucopyranoside (2) on the basis of spectroscopic analysis. 1 exhibited significant cytotoxic activities against human myeloid leukemia HL-60 and human liver cancer HepG2 cells with the IC(50) of 1.3 ± 0.1 and 2.1 ± 0.3 ?M, respectively. 2 showed potential cytotoxic activities against HL-60 and human myeloid leukemia Mata cells with the IC(50) of 5.1 ± 0.4 and 12.1 ± 0.8 ?M, respectively. PMID:20971167

Wu, Yixuan; Zhang, Zhen-Xue; Hu, Hui; Li, Dongmei; Qiu, Guofu; Hu, Xianming; He, Xiangjiu

2011-03-01

320

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

321

Characterization of alkyl polyglycosides by both reversed-phase and normal-phase modes of high-performance liquid chromatography.  

PubMed

Alkyl polyglycosides today represent the most important sugar surfactant. Nonionic sugar surfactants produced via different synthetic routes are mixtures of alkyl homologues, oligomers, anomers and isomers. Alkyl homologues and oligomers of alkyl mono- and diglucosides were separated by reversed-phase high-performance liquid chromatography (HPLC) with methanol-water as the mobile phase using a gradient elution. The gradient was optimized in respect to a simultaneous separation of alkyl glycosides according to their alkyl chain length and alkyl polyoxyethylene glucosides with regard to their length of the polyoxyethylene spacer. The separation of alkyl glycosides into alpha- and beta-anomers was carried out by normal-phase HPLC with isooctane-ethyl acetate (60:40, v/v)-2-propanol in the gradient mode. Light scattering detection was used. Matrix-assisted laser desorption ionization time-of-flight mass spectra of alkyl glucosides and dodecyl glucosides with oxyethylene spacer groups are presented. PMID:11833644

Czichocki, Gunther; Fiedler, Harald; Haage, Klaus; Much, Helmut; Weidner, Steffen

2002-01-18

322

Steviol and steviol-glycoside: glucosyltransferase activities in Stevia rebaudiana Bertoni--purification and partial characterization.  

PubMed

The leaves of Stevia rebaudiana Bertoni contain sweet compounds which are glycosides of diterpene derivative steviol (ent-13-hydroxykaur-16-en-19-oic acid). Its main constituents are stevioside (triglucosylated steviol; 13-O-beta-sophorosyl-19-O-beta-glucosyl-steviol) and rebaudioside-A (tetraglucosylated steviol; 2'-O-beta-glucosyl-13-O-beta-sophorosyl-19-O-beta-glucosyl-stev iol). From the extracts of S. rebaudiana Bertoni, two glucosyltransferases (GTases I and IIB) acting on steviol and steviol-glycosides were isolated, and another distinct activity (GTase IIA) acting on steviol was detected. Purified GTase I (subunit M(r) 24,600) catalyzed glucose transfer from UDP-glucose to steviol and steviolmonoside (steviol-13-O-glucopyranoside), but not to other steviol-glycosides. Apparent Km values were 71.4 microM for steviol and 360 microM for UDP-glucose. GTase IIB (subunit M(r) 30,700) showed a broad substrate specificity, acting on steviol, steviolmonoside, steviolbioside (13-O-beta-sophorosyl-steviol), and stevioside. Apparent Km values were 182 microM for steviol, 44 microM for steviolbioside, 95 microM for stevioside, and 385 microM for UDP-glucose. The two enzymes had a similar optimum pH at 6.5. They also acted effectively on ubiquitous flavonol aglycones, quercetin, and kaempferol and utilized kaempferol at a higher rate than steviol and steviol-glycosides. The apparent Km values of GTase I and IIB for kaempferol were 12 and 31 microM, respectively. PMID:7646064

Shibata, H; Sawa, Y; Oka, T; Sonoke, S; Kim, K K; Yoshioka, M

1995-08-20

323

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

324

Simultaneous Estimation of Glycosidic Isoflavones in Fermented and Unfermented Soybeans by TLC-Densitometric Method.  

PubMed

A simple, accurate and rapid high-performance thin-layer chromatographic (HPTLC) method for the simultaneous quantification of three glycosidic isoflavones (daidzin, genistin and glycitin) in soybean (Glycine max L.) has been established and validated. Chromatography was performed on aluminum foil-backed silica gel 60 F254 HPTLC plates and found compact spots for daidzin, genistin and glycitin (Rf value of 0.39, 0.51 and 0.32, respectively) with mobile phase toluene : ethyl acetate : formic acid : acetic acid in the ratio of 1 : 8 : 1 : 0.5, v/v/v/v. Ultraviolet detection was performed densitometrically at the maximum absorbance wavelength, 260 nm. The method was validated for precision, recovery, robustness, specificity, limit of detection (LOD) and limit of quantification (LOQ), in accordance with the ICH guidelines. The LOD (2.9, 19.3 and 3.5 µg mL(-1)), LOQ (9.03, 58.6 and 10.7 µg mL(-1)), recovery (95.9-106.66, 86.97-106.56 and 98.54-105.65%) and precision (?2.12, ?0.722 and ?0.066) were satisfactory for glycosidic form of isoflavones daidzin, genistin and glycitin, respectively. Soybean variety Kh-09 bragg was found to have relatively higher amount of glycosidic isoflavones, namely daidzin, genistin and glycitin 278, 597.5 and 109.4 µg g(-1), respectively, and after fermentation the glycosidic isoflavones concentration in soybean fermented with Bacillus subtilis strain were decreased significantly after 24 h of incubation; conversely, aglycone isoflavones were increased significantly. The method for quantification of isoflavones in unfermented and fermented soybeans, with good resolution has been developed. PMID:24872524

Puri, Alka; Panda, Bibhu P

2015-02-01

325

Synthesis and evaluation of cardiac glycoside mimics as potential anticancer drugs.  

PubMed

The cardiac glycoside digitoxin, consisting of a steroid core linked to a labile trisaccharide, has been used for centuries for the treatment of congestive heart failure. The well known pharmacological effect is a result of the ability of cardiac glycosides to inhibit the Na(+), K(+)-ATPase. Within recent years cardiac glycosides have furthermore been suggested to possess valuable anticancer activity. To mimic the labile trisaccharide of digitoxin with a stabile carbohydrate surrogate, we have used sulfur linked ethylene glycol moieties of varying length (mono-, di-, tri- or tetra-ethylene glycol), and furthermore used these linkers as handles for the synthesis of bivalent steroids. The prepared compounds were evaluated for their potencies to inhibit the Na(+), K(+)-ATPase and for their cytotoxic effect on cancerous MCF-7 cells. A clear trend is observed in both inhibition and cytotoxic effect, where the bioactivity decreases as the size increases. The most potent Na(+), K(+)-ATPase inhibitors are the compounds with the shortest ethylene glycol chain (K(app) 0.48 ?M) and thiodigitoxigenin (K(app) 0.42 ?M), which both are comparable with digitoxigenin (K(app) 0.52 ?M). For the cancer cell viability assay the shortest mimics were found to have highest efficacy, with the best ligand having a monoethylene glycol unit (IC(50) 0.24 ?M), which was slightly better than digitoxigenin (IC(50) 0.64 ?M), while none of the novel cardiac glycoside mimics display an in vitro effect as high as digitoxin (IC(50) 0.02 ?M). PMID:21421322

Jensen, Marie; Schmidt, Steffen; Fedosova, Natalya U; Mollenhauer, Jan; Jensen, Henrik H

2011-04-01

326

Cardiac glycosides as novel inhibitors of human ether-a-go-go-related gene channel trafficking.  

PubMed

Direct block of the cardiac potassium channel human ether-a-go-go-related gene (hERG) by a large, structurally diverse group of therapeutic compounds causes drug-induced QT prolongation and torsades de pointes arrhythmias. In addition, several therapeutic compounds have been identified more recently that prolong the QT interval by inhibition of hERG trafficking to the cell surface. We used a surface expression assay to identify novel compounds that interfere with hERG trafficking and found that cardiac glycosides are potent inhibitors of hERG expression at the cell surface. Further investigation of digitoxin, ouabain, and digoxin revealed that all three cardiac glycosides reduced expression of the fully glycosylated cell surface form of hERG on Western blots, indicating that channel exit from the endoplasmic reticulum is blocked. Likewise, hERG currents were reduced with nanomolar affinity on long-term exposure. hERG trafficking inhibition was initiated by cardiac glycosides through direct block of Na(+)/K(+) pumps and not via off-target interactions with hERG or another closely associated protein in its processing or export pathway. In isolated guinea pig myocytes, long-term exposure to 30 nM of the clinically used drugs digoxin or digitoxin reduced hERG/rapidly activating delayed rectifier K(+) current (I(Kr)) currents by approximately 50%, whereas three other cardiac membrane currents--inward rectifier current, slowly activating delayed rectifier K(+) current, and calcium current--were not affected. Importantly, 100 nM digitoxin prolonged action potential duration on long-term exposure consistent with a reduction in hERG/I(Kr) channel number. Thus, cardiac glycosides are able to delay cardiac repolarization at nanomolar concentrations via hERG trafficking inhibition, and this may contribute to the complex electrocardiographic changes seen with compounds such as digitoxin. PMID:17095614

Wang, Lu; Wible, Barbara A; Wan, Xiaoping; Ficker, Eckhard

2007-02-01

327

Inhibition of human low density lipoprotein oxidation by flavonols and their glycosides  

Microsoft Academic Search

Antioxidative effects of the flavonols and their glycosides, i.e., quercetin (Q), quercetin galactopyranoside (QG), quercetin rhamnolpyranoside (QR), rutin (R), morin (MO), myrecetin (MY), kaempferol (K) and kaempferol glucoside (KG), against free radical initiated peroxidation of human low density lipoprotein (LDL) were studied. The peroxidation was initiated either by a water-soluble initiator 2,2?-azobis(2-amidino propane hydrochloride) (AAPH), or by cupric ion (Cu2+).

Lifen Hou; Bo Zhou; Li Yang; Zhong-Li Liu

2004-01-01

328

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

329

Anti-Inflammatory Activity of a Novel Flavonol Glycoside from the Bauhinia Variegata Linn  

Microsoft Academic Search

Bauhinia variegata Linn. (Leguminosae) is commonly known as 'Kachnar' in Hindi. It is distributed almost throught India. Its powdered bark is traditionally used for tonic, astrain, ulcers. It is also useful in skin diseases. The roots are used as antidote to snake poison. The present article deals with the isolation and structural elucidation of a novel flavonol glycoside 5,7,3',4'-tetrahydroxy-3-methoxy-7- O

R. N. Yadava; V. Madhu Sudhan Reddy

2003-01-01

330

Two New Triterpene Glycosides from the Vietnamese Sea Cucumber Holothuria scabra  

Microsoft Academic Search

Two new triterpene glycosides, namely holothurin A3 (1) and A4 (2) were isolated from the methanol extract of the sea cucumber,Holothuria scabra, with their structures elucidated from the spectroscopic evidence (1D NMR, 2D NMR, ESI-MS and HRESI-MS). Compounds1 and2 were found to be strongly cytotoxic to both cancer cell lines, KB and Hep-G2, with 50% inhibitory concentrations (IC50) of 0.87

Nguyen Hai Dang; Nguyen Van Thanh; Phan Van Kiem; Le Mai Huong; Chau Van Minh; Young Ho Kim

2007-01-01

331

A critical review of the genetic toxicity of steviol and steviol glycosides  

Microsoft Academic Search

Extracts of the leaves of the stevia plant (Stevia rebaudiana Bertoni) are used to sweeten food and beverages in South America, Japan and China. The components responsible for the sweet properties of the plant are glycosides of steviol, primary stevioside (ent-13-hydroxykaur-16-en-18-oic acid), which is 250–300 times sweeter than sucrose and rebaudiosides A and C. Stevioside and steviol have been subjected

D. J. Brusick

2008-01-01

332

Detailed Kinetic Analysis of a Family 52 Glycoside Hydrolase:  A ?-Xylosidase from Geobacillus stearothermophilus †  

Microsoft Academic Search

Geobacillus stearothermophilusT-6 encodes for a ‚-xylosidase (XynB2) from family 52 of glycoside hydrolases that was previously shown to hydrolyze its substrate with net retention of the anomeric configuration. XynB2 significantly prefers substrates with xylose as the glycone moiety and exhibits a typical bell-shaped pH dependence curve. Binding properties of xylobiose and xylotriose to the active site were measured using isothermal

Tsafrir Bravman; Gennady Zolotnitsky; Valery Belakhov; Gil Shoham; Bernard Henrissat; Timor Baasov; Yuval Shoham

2003-01-01

333

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

334

Positive selection of three chitinase genes of the family 18 of glycoside hydrolases in mammals  

Microsoft Academic Search

The digestive enzyme chitinase degrades chitin, and is found in a wide range of organisms, from prokaryotes to eukaryotes.\\u000a Although mammals cannot synthesize or assimilate chitin, several proteins of the glycoside hydrolase (GH) chitinase family\\u000a GH18, including some with enzymatic activity, have recently been identified from mammalian genomes. Consequently, there is\\u000a growing interest in molecular evolution of this family of

Beibei He; Li Wang; Jinhong Wang; Gang Li; Shuyi Zhang

2009-01-01

335

A novel ?-xylosidase structure from Geobacillus thermoglucosidasius: the first crystal structure of a glycoside hydrolase family GH52 enzyme reveals unpredicted similarity to other glycoside hydrolase folds.  

PubMed

Geobacillus thermoglucosidasius is a thermophilic bacterium that is able to ferment both C6 and C5 sugars to produce ethanol. During growth on hemicellulose biomass, an intracellular ?-xylosidase catalyses the hydrolysis of xylo-oligosaccharides to the monosaccharide xylose, which can then enter the pathways of central metabolism. The gene encoding a G. thermoglucosidasius ?-xylosidase belonging to CAZy glycoside hydrolase family GH52 has been cloned and expressed in Escherichia coli. The recombinant enzyme has been characterized and a high-resolution (1.7 Å) crystal structure has been determined, resulting in the first reported structure of a GH52 family member. A lower resolution (2.6 Å) structure of the enzyme-substrate complex shows the positioning of the xylobiose substrate to be consistent with the proposed retaining mechanism of the family; additionally, the deep cleft of the active-site pocket, plus the proximity of the neighbouring subunit, afford an explanation for the lack of catalytic activity towards the polymer xylan. Whilst the fold of the G. thermoglucosidasius ?-xylosidase is completely different from xylosidases in other CAZy families, the enzyme surprisingly shares structural similarities with other glycoside hydrolases, despite having no more than 13% sequence identity. PMID:24816105

Espina, Giannina; Eley, Kirstin; Pompidor, Guillaume; Schneider, Thomas R; Crennell, Susan J; Danson, Michael J

2014-05-01

336

Antibacterial and antiparasitic activity of oleanolic acid and its glycosides isolated from marigold (Calendula officinalis).  

PubMed

The antibacterial and antiparasitic activities of free oleanolic acid and its glucosides and glucuronides isolated from marigold (Calendula officinalis) were investigated. The MIC of oleanolic acid and the effect on bacterial growth were estimated by A600 measurements. Oleanolic acid's influence on bacterial survival and the ability to induce autolysis were measured by counting the number of cfu. Cell morphology and the presence of endospores were observed under electron and light microscopy, respectively. Oleanolic acid inhibited bacterial growth and survival, influenced cell morphology and enhanced the autolysis of Gram-positive bacteria suggesting that bacterial envelopes are the target of its activity. On the other hand, glycosides of oleanolic acid inhibited the development of L3 Heligmosomoides polygyrus larvae, the infective stage of this intestinal parasitic nematode. In addition, both oleanolic acid and its glycosides reduced the rate of L3 survival during prolonged storage, but only oleanolic acid glucuronides affected nematode infectivity. The presented results suggest that oleanolic acid and its glycosides can be considered as potential therapeutic agents. PMID:18951335

Szakiel, Anna; Ruszkowski, Dariusz; Grudniak, Anna; Kurek, Anna; Wolska, Krystyna I; Doligalska, Maria; Janiszowska, Wirginia

2008-11-01

337

Coping with toxic plant compounds--the insect's perspective on iridoid glycosides and cardenolides.  

PubMed

Specializing on host plants with toxic secondary compounds enforces specific adaptation in insect herbivores. In this review, we focus on two compound classes, iridoid glycosides and cardenolides, which can be found in the food plants of a large number of insect species that display various degrees of adaptation to them. These secondary compounds have very different modes of action: Iridoid glycosides are usually activated in the gut of the herbivores by ?-glucosidases that may either stem from the food plant or be present in the gut as standard digestive enzymes. Upon cleaving, the unstable aglycone is released that unspecifically acts by crosslinking proteins and inhibiting enzymes. Cardenolides, on the other hand, are highly specific inhibitors of an essential ion carrier, the sodium pump. In insects exposed to both kinds of toxins, carriers either enabling the safe storage of the compounds away from the activating enzymes or excluding the toxins from sensitive tissues, play an important role that deserves further analysis. To avoid toxicity of iridoid glycosides, repression of activating enzymes emerges as a possible alternative strategy. Cardenolides, on the other hand, may lose their toxicity if their target site is modified and this strategy has evolved multiple times independently in cardenolide-adapted insects. PMID:21620425

Dobler, Susanne; Petschenka, Georg; Pankoke, Helga

2011-09-01

338

Inhibition of aldose reductase by phenylethanoid glycoside isolated from the seeds of Paulownia coreana.  

PubMed

Aldose reductase (AR) inhibitors have considerable therapeutic potential against diabetic complications and do not increase the risk of hypoglycemia. Through bioassay-guided fractionation of the 70% acetone extract obtained from Paulownia coreana seeds, phenylpropanoid glycosides (compounds 1-4) and 5 phenolic compounds were isolated (compounds 5-9). Their structures were determined on the basis of spectroscopic analysis and comparison with reported data. All the isolates were subjected to in vitro bioassays to evaluate their inhibitory activities against recombinant human aldose reductase (rhAR) and sorbitol formation in human erythrocytes. Phenylethanoid glycosides showed more effective than the phenolic compounds in inhibiting rhAR. Among the compounds, isocampneoside II (3) was found to significantly inhibit rhAR with an IC(50) value of 9.72 µM. In kinetic analyses performed using Lineweaver-Burk plots of 1/velocity and 1/concentration of substrate, isocampneoside II (3) showed uncompetitive inhibition against rhAR. Furthermore, it inhibited sorbitol formation in a rat lens incubated with a high concentration of glucose; this finding indicated that isocampneoside II (3) may effectively prevent osmotic stress in hyperglycemia. Thus, the P. coreana-derived phenylethanoid glycoside isocampneoside II (3) may have a potential therapeutics against diabetic complications. PMID:21212537

Kim, Jin Kyu; Lee, Yeon Sil; Kim, Seon Ha; Bae, Young Soo; Lim, Soon Sung

2011-01-01

339

Release of adenine nucleotide metabolites by toxic concentrations of cardiac glycosides.  

PubMed

In isolated perfused guinea-pig hearts the effect of toxic concentrations of cardiac glycosides on the release of the adenine nucleotide metabolites adenosine, inosine, hypoxanthine, xanthine, and uric acid was investigated. Digoxin concentrations of 0.03-1 mumol.l-1 produced moderate to severe tachyarrhythmias. Large amounts of metabolites were released by concentrations of 0.1 mumol.l-1, and higher. Occurrence of glycoside-induced ventricular fibrillation was associated with a particularly high release. Metabolite release was also obtained when fibrillation was elicited electrically in normal control hearts, or in hearts receiving simultaneously a marginally toxic digoxin concentration (0.03 mumol.l-1). Digoxin-induced tachyarrhythmias and metabolite release were almost completely prevented by a high potassium concentration in the coronary perfusion fluid (8.1 mmol.l-1). The antiarrhythmic effect was also obtained with lidocaine (60 mumol.l-1), but the release was only partially antagonized. Similar results concerning arrhythmias and metabolite release as with digoxin were obtained with ouabain. The findings suggest that the decrease in myocardial ATP observed in glycoside-intoxicated heart preparations is partly due to the loss of nucleotide precursor substances. Moreover, it appears likely that liberated adenosine in the interstitium of severely intoxicated heart preparations reaches pharmacologically effective concentrations. PMID:7826306

Bernauer, W

1994-01-01

340

A male gift to its partner? Cyanogenic glycosides in the spermatophore of longwing butterflies (Heliconius)  

NASA Astrophysics Data System (ADS)

Males of several insect species transfer nuptial gifts to females during mating, typically in the form of a protein-rich spermatophore. In chemically defended species, males could potentially enhance such a gift with chemicals that help protect the female, her eggs, or both. This was shown for lepidopteran species that accumulate pyrrolizidine alkaloids. Most Heliconius butterflies are presumably protected from predators by virtue of de novo synthesized and/or sequestered cyanogenic glycosides. Males of Heliconius species are known to transfer nutritional gifts to the females but whether defensive chemicals could also be transferred is not known. To ascertain whether transfer of cyanogens occurs, we dissected freshly mated females from nine different Heliconius species and analyzed spermatophores for cyanogenic glycosides. We found cyanogens in the spermatophores of all nine species. This is the first time cyanogenic glycosides are reported in the spermatophores of arthropods. We discuss the implications of these findings for Heliconius biology and for other cyanogenic insects as well. We suggest that chemically defended species commonly lace their nuptial gifts with defensive chemicals to improve gift quality.

Cardoso, Márcio Zikán; Gilbert, Lawrence E.

2007-01-01

341

Inhibitory effects of Thai plants beta-glycosides on Trichomonas vaginalis.  

PubMed

Trichomoniasis is now an important health problem in developing countries. Although metronidazole has so far been widely used to treat this disease, the prevalence of metronidazole-resistant protozoa and unpleasant adverse effects have been found. In this study, natural products purified from Thai plants were, therefore, investigated for their effectiveness against Trichomonas vaginalis. The minimal inhibitory concentrations for all beta-glycosides against Trichomonas vaginalis at 24 h were in a range of 6.25-12.5 microM. In addition, torvoside A and H were found to be more potent than their corresponding aglycones, deglucosylated torvoside A and H, while other beta-glycosides were generally as active as their corresponding aglycones. The cytotoxicity of these compounds was also determined. Except for dalcochinin, none of the tested compounds showed cytotoxicity against Vero and cancer cell lines (KB and MCF-7), having IC(50) values greater than 50 microg/ml. In conclusion, beta-glycosides and several aglycones showed selective inhibition against Trichomonas vaginalis without harmful effect to mammalian cells. PMID:18463895

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

2008-07-01

342

Variegatusides: new non-sulphated triterpene glycosides from the sea cucumber Stichopus variegates semper.  

PubMed

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 B?. 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

2014-04-01

343

[Residues affecting hydrolysis of soy isoflavone glycosides, stability and catalytic properties of Thermotoga maritime ?-glucosidase].  

PubMed

The thermostable ?-glucosidase A (TmBglA) from Thermotoga maritime is a promising biocatalyst for production of isoflavone aglycones. Use of enzymes with high specificity for soy isoflavone conjugates is however essential for efficient hydrolysis. The effect of the amino acids located in the aglycone binding pocket with non-conserved residues between specificity groups in family 1 glycoside hydrolase (GH1) was studied using wild-type TmBglA and 3 exchange mutants (MI-TmBglA, M2-TmBglA, M1M2-TmBglA). Three mutants were expressed in Escherichia coli, purified and characterized. They had shifts in both optimum tem- perature and thermal stability, and their narrowing pH-activity curve caused by removing the ionized side chain in mutation. All mutants demonstrated the decreased catalytic efficiency more effectively revealed with natural glycoside, salicin, than with artificial substrate, p-nitrophenyl-?-D-glucopyranoside, suggesting that' these amino acids are the key residues to determine aglycone specificity. A lower hydrolysis of genistin and daidzin for M2-TmBglA than M1-TmBglA indicated that L400, A407 and E408 being preferable to V170, A171, V173, G 174 and H180 residues of Tm-BglA could be essential for soy isoflavone glycoside binding and catalysis. PMID:25508647

2013-01-01

344

[Residues affecting hydrolysis of soy isoflavone glycosides, stability and catalytic properties of Thermotoga maritime ?-glucosidase].  

PubMed

The thermostable ?-glucosidase A (TmBglA) from Thermotoga maritime is a promising biocatalyst for production of isoflavone aglycones. Use of enzymes with high specificity for soy isoflavone conjugates is however essential for efficient hydrolysis. The effect of the amino acids located in the aglycone binding pocket with non-conserved residues between specificity groups in family 1 glycoside hydrolase (GH1) was studied using wild-type TmBglA and 3 exchange mutants (MI-TmBglA, M2-TmBglA, M1M2-TmBglA). Three mutants were expressed in Escherichia coli, purified and characterized. They had shifts in both optimum tem- perature and thermal stability, and their narrowing pH-activity curve caused by removing the ionized side chain in mutation. All mutants demonstrated the decreased catalytic efficiency more effectively revealed with natural glycoside, salicin, than with artificial substrate, p-nitrophenyl-?-D-glucopyranoside, suggesting that' these amino acids are the key residues to determine aglycone specificity. A lower hydrolysis of genistin and daidzin for M2-TmBglA than M1-TmBglA indicated that L400, A407 and E408 being preferable to V170, A171, V173, G 174 and H180 residues of Tm-BglA could be essential for soy isoflavone glycoside binding and catalysis. PMID:25474868

Xue, Y; Song, X; Sun, H; Cao, Z

2013-01-01

345

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

346

GH97 is a new family of glycoside hydrolases, which is related to the ?-galactosidase superfamily  

PubMed Central

Background As a rule, about 1% of genes in a given genome encode glycoside hydrolases and their homologues. On the basis of sequence similarity they have been grouped into more than ninety GH families during the last 15 years. The GH97 family has been established very recently and initially included only 18 bacterial proteins. However, the evolutionary relationship of the genes encoding proteins of this family remains unclear, as well as their distribution among main groups of the living organisms. Results The extensive search of the current databases allowed us to double the number of GH97 family proteins. Five subfamilies were distinguished on the basis of pairwise sequence comparison and phylogenetic analysis. Iterative sequence analysis revealed the relationship of the GH97 family with the GH27, GH31, and GH36 families of glycosidases, which belong to the ?-galactosidase superfamily, as well as a more distant relationship with some other glycosidase families (GH13 and GH20). Conclusion The results of this study show an unexpected sequence similarity of GH97 family proteins with glycoside hydrolases from several other families, that have (?/?)8-barrel fold of the catalytic domain and a retaining mechanism of the glycoside bond hydrolysis. These data suggest a common evolutionary origin of glycosidases representing different families and clans. PMID:16131397

Naumoff, Daniil G

2005-01-01

347

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

348

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.

2012-08-03

349

Content determination of the flavonoids in the different parts and different species of Abelmoschus esculentus L. by reversed phase-high performance liquid chromatograph and colorimetric method  

PubMed Central

Background: This research will establish the ultraviolet colorimetric method to determine the total flavonoid content in different species and different parts of Abelmoschus esculentus L. Materials and Methods: We establish the reversed-phase high-performance liquid chromatograph (RP-HPLC) method to determine the content of the three flavonoid glycosides in different species and different parts of the A. esculentus. Adopt the NaNO2-Al (NO3)3-NaOH colorimetric method to determine the total flavonoid content; at the same time, adopt the RP-HPLC method to determine the contents of the three flavonoid glycosides. Using the methods of ultraviolet colorimetry and RP-HPLC, we determined and analyzed the total flavonoid content and the content of the three flavonoid glycosides in different species and different parts of A. esculentus. Results: There are great distribution differences of the total flavonoids and the three flavonoid glycosides in different species and parts of A. esculentus. Among them, the content of the effective constituents in the flower is relatively high, next is in the fruit. In the different species of A. esculentus, the content of the flavonoids of finger relatively high. The HPLC method established in this research is simple and convenient and its results are accurate and reliable. In addition, it has a very good repeatability. Conclusion: The results provided the reference data for the medicinal use of A. esculentus and it can be used in quality analyzing of its effective constituents. PMID:25210315

Lin, Yin; Lu, Min-feng; Liao, Hai-bing; Li, Yu-xian; Han, Wei; Yuan, Ke

2014-01-01

350

Quantitative determination of flavonoids and cycloartanol glycosides from aerial parts of Sutherlandia frutescens (L.) R. BR. by using LC-UV/ELSD methods and confirmation by using LC–MS method  

PubMed Central

This paper describes the first analytical method for the determination of four flavonoids (sutherlandins A–D) and four cycloartanol glycosides (sutherlandiosides A–D) from the aerial parts of Sutherlandia frutescens (L.) R. Br. A separation by HPLC was achieved by using a reversed phase (RP-18) column, PDA with ELS detection, and a water/acetonitrile gradient as the mobile phase. The wavelength used for quantification of four flavonoids with the diode array detector was 260 nm. Owing to their low UV absorption, the cycloartanol glycosides were detected by evaporative light scattering. The method was validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). The limits of detection and limits of quantification of eight compounds were found to be in the range from 0.1 to 7.5 µg/mL and 0.5 to 25 µg/mL, respectively. The analysis of products showed considerable variation of 1.099–5.224 mg/average weight for the major compound, sutherlandioside B. The eight compounds in plant sample and products of S. frutescens were further confirmed by LC–ESI-TOF. This method involved the use of the [M+H]+ and [M+Na]+ ions in the positive ion mode with extractive ion monitoring (EIM). PMID:20122811

Avula, Bharathi; Wang, Yan-Hong; Smillie, Troy J.; Fu, Xiang; Li, Xing Cong; Mabusela, Wilfred; Syce, James; Johnson, Quinton; Folk, William; Khan, Ikhlas A.

2012-01-01

351

Quantitative determination of flavonoids and cycloartanol glycosides from aerial parts of Sutherlandia frutescens (L.) R. BR. by using LC-UV/ELSD methods and confirmation by using LC-MS method.  

PubMed

This paper describes the first analytical method for the determination of four flavonoids (sutherlandins A-D) and four cycloartanol glycosides (sutherlandiosides A-D) from the aerial parts of Sutherlandia frutescens (L.) R. Br. A separation by HPLC was achieved by using a reversed phase (RP-18) column, PDA with ELS detection, and a water/acetonitrile gradient as the mobile phase. The wavelength used for quantification of four flavonoids with the diode array detector was 260 nm. Owing to their low UV absorption, the cycloartanol glycosides were detected by evaporative light scattering. The method was validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). The limits of detection and limits of quantification of eight compounds were found to be in the range from 0.1 to 7.5 microg/mL and 0.5 to 25 microg/mL, respectively. The analysis of products showed considerable variation of 1.099-5.224 mg/average weight for the major compound, sutherlandioside B. The eight compounds in plant sample and products of S. frutescens were further confirmed by LC-ESI-TOF. This method involved the use of the [M+H](+) and [M+Na](+) ions in the positive ion mode with extractive ion monitoring (EIM). PMID:20122811

Avula, Bharathi; Wang, Yan-Hong; Smillie, Troy J; Fu, Xiang; Li, Xing Cong; Mabusela, Wilfred; Syce, James; Johnson, Quinton; Folk, William; Khan, Ikhlas A

2010-06-01

352

Force-field parameters of the Psi and Phi around glycosidic bonds to oxygen and sulfur atoms.  

PubMed

The Psi and Phi torsion angles around glycosidic bonds in a glycoside chain are the most important determinants of the conformation of a glycoside chain. We determined force-field parameters for Psi and Phi torsion angles around a glycosidic bond bridged by a sulfur atom, as well as a bond bridged by an oxygen atom as a preparation for the next study, i.e., molecular dynamics free energy calculations for protein-sugar and protein-inhibitor complexes. First, we extracted the Psi or Phi torsion energy component from a quantum mechanics (QM) total energy by subtracting all the molecular mechanics (MM) force-field components except for the Psi or Phi torsion angle. The Psi and Phi energy components extracted (hereafter called "the remaining energy components") were calculated for simple sugar models and plotted as functions of the Psi and Phi angles. The remaining energy component curves of Psi and Phi were well represented by the torsion force-field functions consisting of four and three cosine functions, respectively. To confirm the reliability of the force-field parameters and to confirm its compatibility with other force-fields, we calculated adiabatic potential curves as functions of Psi and Phi for the model glycosides by adopting the Psi and Phi force-field parameters obtained and by energetically optimizing other degrees of freedom. The MM potential energy curves obtained for Psi and Phi well represented the QM adiabatic curves and also these curves' differences with regard to the glycosidic oxygen and sulfur atoms. Our Psi and Phi force-fields of glycosidic oxygen gave MM potential energy curves that more closely represented the respective QM curves than did those of the recently developed GLYCAM force-field. PMID:19396813

Saito, Minoru; Okazaki, Isao

2009-12-01

353

Reversal of momentum relaxation.  

PubMed

A new phenomenon of momentum relaxation reversal has been discovered experimentally and explained theoretically for dipolar spin waves in magnetic garnet films. It is shown that the process of momentum relaxation, caused by the scattering of a signal wave on defects, can be reversed, and the signal can be restituted after it left the scattering region. The reversal of momentum relaxation is achieved by frequency-selective parametric amplification of a narrow band of scattered waves having low group velocities and frequencies close to the frequency of the original signal wave. The phenomenon can be used for the development of a new type of active microwave delay lines. PMID:11384381

Melkov, G A; Kobljanskyj, Y V; Serga, A A; Tiberkevich, V S; Slavin, A N

2001-05-21

354

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

355

Effects of pregnane glycosides on food intake depend on stimulation of the melanocortin pathway and BDNF in an animal model.  

PubMed

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

2013-02-27

356

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

357

Tektites and Geomagnetic Reversals  

Microsoft Academic Search

THE microscopic glassy objects which occur in sediments deposited in the Australasian area during and shortly after the last magnetic polarity reversal are apparently tektites (see succeeding communication). The last reversal occurred 0.7 × 106 yr ago: potassium-argon dates1 indicate that the Australasian tektites were formed 0.7 × 106 yr ago. The tektites were formed and deposited at the same

Bill Glass; Bruce C. Heezen

1967-01-01

358

Structural and Functional Analysis of a Glycoside Hydrolase Family 97 Enzyme from Bacteroides thetaiotaomicron*  

PubMed Central

SusB, an 84-kDa ?-glucoside hydrolase involved in the starch utilization system (sus) of Bacteroides thetaiotaomicron, belongs to glycoside hydrolase (GH) family 97. We have determined the enzymatic characteristics and the crystal structures in free and acarbose-bound form at 1.6Å resolution. SusB hydrolyzes the ?-glucosidic linkage, with inversion of anomeric configuration liberating the ?-anomer of glucose as the reaction product. The substrate specificity of SusB, hydrolyzing not only ?-1,4-glucosidic linkages but also ?-1,6-, ?-1,3-, and ?-1,2-glucosidic linkages, is clearly different from other well known glucoamylases belonging to GH15. The structure of SusB was solved by the single-wavelength anomalous diffraction method with sulfur atoms as anomalous scatterers using an in-house x-ray source. SusB includes three domains as follows: the N-terminal, catalytic, and C-terminal domains. The structure of the SusB-acarbose complex shows a constellation of carboxyl groups at the catalytic center; Glu532 is positioned to provide protonic assistance to leaving group departure, with Glu439 and Glu508 both positioned to provide base-catalyzed assistance for inverting nucleophilic attack by water. A structural comparison with other glycoside hydrolases revealed significant similarity between the catalytic domain of SusB and those of ?-retaining glycoside hydrolases belonging to GH27, -36, and -31 despite the differences in catalytic mechanism. SusB and the other retaining enzymes appear to have diverged from a common ancestor and individually acquired the functional carboxyl groups during the process of evolution. Furthermore, sequence comparison of the active site based on the structure of SusB indicated that GH97 included both retaining and inverting enzymes. PMID:18981178

Kitamura, Momoyo; Okuyama, Masayuki; Tanzawa, Fumiko; Mori, Haruhide; Kitago, Yu; Watanabe, Nobuhisa; Kimura, Atsuo; Tanaka, Isao; Yao, Min

2008-01-01

359

Biological and taxonomic perspective of triterpenoid glycosides of sea cucumbers of the family Holothuriidae (Echinodermata, Holothuroidea).  

PubMed

Since the discovery of saponins in sea cucumbers, more than 150 triterpene glycosides have been described for the class Holothuroidea. The family Holothuriidae has been increasingly studied in search for these compounds. With many species awaiting recognition and formal description this family currently consists of five genera and the systematics at the species-level taxonomy is, however, not yet fully understood. We provide a bibliographic review of the triterpene glycosides that has been reported within the Holothuriidae and analyzed the relationship of certain compounds with the presence of Cuvierian tubules. We found 40 species belonging to four genera and 121 compounds. Holothurin A and B are the most common saponins for Actinopyga, Holothuria, and Pearsonothuria. The genus Bohadschia presents mainly bivittoside C and D. Actinopyga has only sulfated saponins mainly oxidized, Bohadschia non-sulfated ones mainly non-oxidized, Holothuria and Pearsonothuria contain both types of compounds, mainly oxidized. Within the genus Holothuria, the subgenus Panningothuria only has non-sulfated saponins. The presence of sulfated and non-sulfated compounds seemingly relates to the expellability or the absence of Cuvierian tubules and the temporal or permanent concealing habits of the species. Our study concludes that better insights into the systematic distribution of saponins in Holothuriidae will only be possible if the identifications of the investigated species are confirmed by a taxonomist, especially in this group wherein cryptic species and variation between life-history stages are common and yet poorly understood. Understanding of saponin distribution within the Holothuriidae would also benefit from a stabilization of triterpene glycoside nomenclature. PMID:25263252

Honey-Escandón, Magali; Arreguín-Espinosa, Roberto; Solís-Marín, Francisco Alonso; Samyn, Yves

2015-02-01

360

Octopus glycosides: multivalent molecular platforms for testing carbohydrate recognition and bacterial adhesion.  

PubMed

Multivalency of carbohydrate-protein interactions is critical for cell adhesion, including attachment of bacteria to their host cells. To investigate specific parameters of multivalency effects, a variety of multivalent glycoconjugates has been designed according to different mimetic approaches. Some 15years ago, carbohydrates were elaborated as multivalent scaffold molecules for the preparation of carbohydrate-centred 'octopus glycosides' as well as of other carbohydrate-centred glycoconjugates. The beginning of this research is reported from a historical perspective and a selection of interesting applications is highlighted. PMID:25104394

Lindhorst, Thisbe K; Dubber, Michael

2014-07-01

361

A New Benzofuran Glycoside and Indole Alkaloids from a Sponge-Associated Rare Actinomycete, Amycolatopsis sp.  

PubMed Central

Three new secondary metabolites, amycofuran (1), amycocyclopiazonic acid (2), and amycolactam (3), were isolated from the sponge-associated rare actinomycete Amycolatopsis sp. Based on combined spectroscopic analyses, the structures of 1–3 were determined to be a new benzofuran glycoside and new indole alkaloids related to cyclopiazonic acids, a class that has previously only been reported in fungi. The absolute configurations of 1 and 3 were deduced by ECD calculations, whereas that of 2 was determined using the modified Mosher method. Amycolactam (3) displayed significant cytotoxicity against the gastric cancer cell line SNU638 and the colon cancer cell line HCT116. PMID:24759001

Kwon, Yun; Kim, Seong-Hwan; Shin, Yoonho; Bae, Munhyung; Kim, Byung-Yong; Lee, Sang Kook; Oh, Ki-Bong; Shin, Jongheon; Oh, Dong-Chan

2014-01-01

362

A trinorsesterterpene glycoside from the North American fern Woodwardia virginica (L.) Smith.  

PubMed

A new trinorsesterterpene glycoside was isolated from the ethanol extract of the American fern Woodwardia virginica having a 3-[6-(4,8-dimethyl-nona-1,3,7-trienyl)-4-hydroxy-2,6-dimethyl-cyclohex-1-enyl]-3-hydroxypropionic acid, as the aglycone and a saccharide moiety linked at C-4 to glucoses, xylose or arabinofuranose. The structure was elucidated using extensive spectroscopic analysis (1D and 2D NMR, MS, IR and UV) including determination of absolute stereochemistry by means of the MTPA and PGME derivatives and also by chemical methods. PMID:12895532

Hanus, Lumír O; Rezanka, Tomás; Dembitsky, Valery M

2003-08-01

363

Glomerxanthones A-C, three xanthonolignoid C-glycosides from Polygala glomerata Lour.  

PubMed

Three novel xanthonolignoid C-glycosides, glomexanthones A-C, with a trans-dihydrobenzofuran on B ring and a 2-hydroxymethyl-5-hydroxyl-2-pentenoic acid moiety in the sugar chain were isolated from an ethanol extract of Polygala glomerata. Their structures and absolute configurations were characterized by extensive NMR, MS, and CD spectroscopic studies. Screening results indicated that compounds 1-3 showed moderate neuroprotective effects on L-Glutamic acid-induced cellular damage in human neuroblastoma SK-N-SH cells. PMID:24369310

Li, Chuang-Jun; Yang, Jing-Zhi; Yu, Shi-Shan; Zhao, Chun-Yang; Peng, Ying; Wang, Xiao-Liang; Zhang, Dong-Ming

2014-03-01

364

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

365

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

366

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

367

Steroidal saponins obtained by biotransformation of total furostanol glycosides from Dioscorea zingiberensis with Absidia coerulea.  

PubMed

Five new steroidal saponins (1-5) were isolated from the fermentation broth of total furostanol glycosides from tubers of Dioscorea zingiberensis C.H. Wright incubated with a fungal, Absidia coerulea AS 3.3389, along with known saponins, zingiberensis new saponin (6), deltonin (7), prosapogenin A of dioscin (8), and protobioside (9), and their structures were established by NMR spectroscopy and mass spectrometry as well as by comparison with previously reported spectral data in the literatures. The induced effects in vitro on rat platelet aggregation of all compounds were evaluated. PMID:25498025

Pang, Xu; Wen, Di; Zhao, Yang; Xiong, Cheng-Qi; Wang, Xiao-Qin; Yu, Li-Yan; Ma, Bai-Ping

2015-01-30

368

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

2014-01-01

369

Ginsenoside Rg 5 , a genuine dammarane glycoside from Korean red ginseng  

Microsoft Academic Search

A genuine dammarane glycoside, named ginsenoside Rg5, has been isolated by repeated column chromatography and preparative HPLC from the MeOH extract of Korean red ginseng (Panax ginseng C.A. Meyer). The chemical structure of ginsenoside Rg5 was determined as 3-O-[?-D-glucopyranosyl (1?2)-?-D-glucopyranosyl] dammar-20(22),24-diene-3?,12?-diol by spectral and chemical\\u000a methods. The stereostructure of a double bond at C-20(22) of ginsenoside Rg5 was characterized as

Shin Il Kim; Jeong Hill Park; Jae-Ha Ryu; Jong Dae Park; You Hui Lee; Jae-Hyun Park; Tae-Hee Kim; Jong Moon Kim; Nam-In Baek

1996-01-01

370

Teucrium polium Phenylethanol and Iridoid Glycoside Characterization and Flavonoid Inhibition of Biofilm-Forming Staphylococcus aureus.  

PubMed

The chemical composition and biofilm regulation of 15 metabolites from Teucrium polium are reported. Compounds were isolated from a CH2Cl2-MeOH extract of the aerial parts of the plant and included iridoid and phenylethanol glycosides and a monoterpenoid, together with nine known compounds. The structures were elucidated based on standard spectroscopic (UV, (1)H and (13)C NMR), 2D NMR ((1)H-(1)H COSY, HMQC, HMBC, and NOESY), and/or LC-ESIMS/MS data analyses. Inhibition of the biofilm-forming strain Staphylococcus aureus was observed with exposure to compounds 7 and 8. PMID:25524452

Elmasri, Wael A; Yang, Tianjiao; Tran, Phat; Hegazy, Mohamed-Elamir F; Hamood, Abdul N; Mechref, Yehia; Paré, Paul W

2015-01-23

371

A new phenolic glycoside from Chamaecyparis obtusa var. breviramea f. crippsii.  

PubMed

A new phenolic glycoside, 3-methoxyphenol 1-O-?-L-rhamnopyranosyl-(1?6)- O-?-D-glucopyranoside (1), was isolated from the 90% acetone extract of the branches and leaves of Chamaecyparis obtusa var. breviramea f. crippsii along with another 10 known phenolics 2-11. Their structures were determined mainly by means of MS, 1D- and 2D-NMR data. Cytotoxicities of compounds 3 and 5-11 were tested on BGC-823, Hela and A549 cancer cell lines, the results showed that compound 8 was bioactive and its IC(50) values were 6.9, 29.7 and 52.9 ?M, respectively. PMID:23334571

Zhang, Yu-Mei; Xu, Jian; Xiao, Lin; Zeng, Guang-Zhi; Sun, Zhang-Hua; Tan, Ning-Hua

2013-01-01

372

Two new flavonol glycosides from the leaves of Cleome chelidonii L.f.  

PubMed

From the leaves of Cleome chelidonii L.f., two new flavonol glycosides, named cleomesides A (1) and B (2), and four known compounds, quercetin 3-O-?-glucopyranosyl(1 ? 2)-?-rhamnoside-7-O-?-rhamnoside (3), ethyl ?-galactopyranoside (4), adenine (5) and glycerol monostearate (6), were isolated. The structures of all isolated compounds (1-6) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3-6) were further compared with the reported data for these compounds. PMID:25367696

Minh, Phan Nhat; Dinh Tri, Mai; Tan Phat, Nguyen; Dat, Bui Trong; Hanh, Nguyen Ngoc; Luan, Ngo Quoc; Thanh, Ma Thi Thu; Huynh, Chung Hoang

2014-11-01

373

Three new phenolic glycosides from the Tibetan medicinal plant Aconitum tanguticum.  

PubMed

Three new phenolic glycosides, such as (Z)-sinapic acid-4-O-?-d-allopyranoside (1), 3,4-dihydroxyphenethoxy-8-O-?-d-[6-O-(4-O-?-d-glucopyranosyl)-feruloyl]-glucopyranoside (2), and 4-dihydroxyphenethoxy-8-O-?-d-[6-O-(4-O-?-d-glucopyranosyl)-feruloyl]-glucopyranoside (3) were isolated from the EtOH extract of whole plant of Aconitum tanguticum (Maxim.) Stapf. The structures of the new compounds were elucidated by spectroscopic methods, and the total (1)H NMR and (13)C NMR chemical shifts were assigned. PMID:23768043

Xu, Lu; Luo, Ming; Lin, Li-Me; Zhang, Xiao; Li, Chun; Wang, Zhi-Min; Luo, Yong-Ming

2013-07-01

374

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

375

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

376

Effect of Morinda citrifolia fruit extract and its iridoid glycosides on blood fluidity.  

PubMed

The aim of this study was to investigate the effect of Morinda citrifolia fruit on blood fluidity. M. citrifolia fruit extract (MCF-ext) was investigated for its influence on blood aggregation and fibrinolysis. MCF-ext inhibited polybrene-induced erythrocyte aggregation and thrombin activity. The fibrinolytic activity of MCF-ext, in the euglobulin lysis time test and fibrin plate assay, is reported here for the first time. One of the active compounds was an iridoid glycoside, asperulosidic acid. The results indicated that MCF-ext is a potentially useful health food which is capable of improving blood flow and preventing lifestyle-related diseases. PMID:24604344

Murata, Kazuya; Abe, Yumi; Futamura-Masuda, Megumi; Uwaya, Akemi; Isami, Fumiyuki; Deng, Shixin; Matsuda, Hideaki

2014-07-01

377

Molecular cloning of glycoside hydrolase family 45 cellulase genes from brackish water clam Corbicula japonica  

Microsoft Academic Search

We previously reported endogenous Glycoside Hydrolase Family (GHF) 9 ?-1,4-glucanase gene, CjCel9A, from common Japanese freshwater clam Corbicula japonica. Here we identified another endogenous ?-1,4-glucanase genes which belong to GHF45 (CjCel45A, CjCel45B). Both genes encode ORF of 627 bp corresponding to 208 amino acids. CjCel45A and CjCel45B are different in 5? and 3?-untranslated regions and six nucleotides in the ORF. CjCEL45

Kentaro Sakamoto; Haruhiko Toyohara

2009-01-01

378

A new lignan glycoside from Chamaecyparis obtusa var. breviramea f. crippsii.  

PubMed

A new lignan glycoside, (-)-(8S, 8'R)-thujastandin-4-O-beta-D-glucopyranoside (1), together with fourteen known lignanoids (2-15) and one coumarin (16) were isolated from the branches and leaves of Chamaecyparis obtusa var. breviramea f. crippsii. Their structures were elucidated by extensive spectroscopic and spectrometric analysis. Compound 16 exhibited cytotoxicity against A549, BGC-823 and Hela cell lines with IC50 values of 25.9, 20.9 and 18.5 microM, respectively. PMID:24689293

Xu, Jian; Zeng, Guang-Zhi; Chen, Ke-Li; Liu, Yi-Mei; Sun, Zhang-Hua; Tan, Ning-Hua; Zhang, Yu-Mei

2014-02-01

379

Detection and Isolation of New Glycosides in Culture Broths of Streptomyces hygroscopicus1  

PubMed Central

Elbein, A. D. (Purdue University, Lafayette, Ind.) J. A. Holowczak, Henry Koffler, and H. R. Garner. Detection and ìsolation of new glycosides in culture broths of Streptomyces hygroscopicus. J. Bacteriol. 91:604–608. 1966.—Four new compounds not previously reported have been isolated and purified from the culture broths of Streptomyces hygroscopicus. The data presented suggest that these compounds may be structurally related to hygromycin A, having similar aglycons but differing in their sugar moieties. Two of the compounds apparently contain d-glucose or l-fucose as their sugar components. The others, like hygromycin A, form crystalline 2,4-dinitrophenylhydrazones, and may contain unusual keto sugars. PMID:5883099

Elbein, A. D.; Holowczak, J. A.; Koffler, Henry; Garner, H. R.

1966-01-01

380

Patagonicosides B and C, two Antifungal Sulfated Triterpene Glycosides from the Sea Cucumber Psolus patagonicus  

PubMed Central

Two new triterpene glycosides, patagonicosides B (2) and C (3), together with the known patagonicoside A (1), have been isolated from the ethanolic extract of the sea cucumber Psolus patagonicus. The structures of the new compounds were established on the basis of extensive NMR spectroscopy (1H and13C NMR,1H–1H COSY, HMBC, HSQC, TOCSY, and NOESY), HRESIMS, and chemical transformations. Compounds 1–3 and their desulfated analogs showed antifungal activity against the phytopathogenic fungus Cladosporium cladosporoides in a dose dependent activity. PMID:21404430

Careaga, Valeria P.; Muniain, Claudia; Maier, Marta S.

2013-01-01

381

Two new triterpene glycosides from the Vietnamese sea cucumber Holothuria scabra.  

PubMed

Two new triterpene glycosides, namely holothurin A3 (1) and A4 (2) were isolated from the methanol extract of the sea cucumber, Holothuria scabra, with their structures elucidated from the spectroscopic evidence (1D NMR, 2D NMR, ESI-MS and HRESI-MS). Compounds 1 and 2 were found to be strongly cytotoxic to both cancer cell lines, KB and Hep-G2, with 50% inhibitory concentrations (IC50) of 0.87 and 0.32 microg/mL (for compound 1) and of 1.12 and 0.57 microg/mL (for compound 2), respectively. PMID:18087805

Dang, Nguyen Hai; Thanh, Nguyen Van; Kiem, Phan Van; Huong, Le Mai; Minh, Chau Van; Kim, Young Ho

2007-11-01

382

New diterpene glycosides of the fungus Acremonium striatisporum isolated from a sea cucumber.  

PubMed

Three new diterpene glycosides, virescenosides O (1), P (2), and Q (3), have been isolated from a marine strain of Acremonium striatisporum KMM 4401 associated with the holothurian Eupentacta fraudatrix. Their structures were determined on the basis of HRMALDIMS and NMR data as beta-D-altropyranosido-19-isopimara-8(14),15-diene-7alpha,3beta-diol (1), beta-D-altropyranosido-19-7-oxoisopimara-8(9),15-diene-3beta-ol (2), and beta-D-mannopyranosido-19-isopimara-7,15-diene-3beta-ol (3). The cytotoxic activity of the virescenosides was examined. PMID:12027733

Afiyatullov, Shamil Sh; Kalinovsky, Anatoly I; Kuznetsova, Tatyana A; Isakov, Vladimir V; Pivkin, Mikhail V; Dmitrenok, Pavel S; Elyakov, George B

2002-05-01

383

[Mechanism of the contraceptive action of the triterpene glycosides from the rock jasmine Androsace septentrionalis L].  

PubMed

The sum of triterpene glycosides of Androsace septentrionalis L. (a plant of genus Primula) was shown to change the concentrations of lutropin and follitropin in the hypophysis and plasma and the ratio of these hormones in the blood plasma in the active phase of the cycle. This leads to the change of the ovarian hormonal activity in the direction of predominance of the estrogenic action and an increase of the uterine contractile activity that can be of certain significance in manifestation of the contraceptive effect. PMID:3086118

Mats, M N; Savchenko, O N

1986-01-01

384

Triterpene glycosides from Androsace septentrionalis . The structure of androseptosides C 1 and D 1  

Microsoft Academic Search

When androseptosides C, and D, were methylated by Hakomori's method [3], followed by methanolysis of the permethylated androseptosides with 72% perchloric acid in methanol (I: i0), methyl 2,3,4-tri-O-methyl-L-arabinopyranoside, methyl 3,4-di-O-methyl-L-arabinoside, and methyl 2,3,6-tri-O-methyl-D-glucopyranoside were obtained. The methyl glycosides were identified with the aid of GLC in the presence of markers (3.2-m column filled with 5% of XE 60 on Chromaton

P. K. Kintya; N. M. Pirozhkova

1982-01-01

385

Microphynolides A and B, new spiro-?-lactone glycosides from Thymelaea microphylla.  

PubMed

Two new spiro-?-lactone glycosides named microphynolide A (1) and microphynolide B (2), together with twelve known compounds including five biflavonoids namely neochamaejasmin A, neochamaejasmin B, daphnodorin B, genkwanol A and stelleranol, one bis-coumarin daphnoretin, two lignans called pinoresinol and matairesinol, one flavonoid glucoside, tiliroside, a sinapyl alcohol glucoside, syringin, and two phytosterols, ?-sitosterol and ?-sitosterol-3-O-glucoside, were isolated from ethyl acetate extracts of the aerial parts and roots of the plant Thymelaea microphylla Coss. and Dur. All the isolated compounds were characterised by using spectroscopic methods and comparison with the literature data. PMID:25076123

Ghanem, Hasna; Haba, Hamada; Marcourt, Laurence; Benkhaled, Mohammed; Wolfender, Jean-Luc

2014-01-01

386

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

387

Ophiopojaponin D, a new phenylpropanoid glycoside from Ophiopogon japonicus Ker-Gawl.  

PubMed

A new phenolic glycoside, ophiopojaponin D (1), together with two known compounds, was isolated from the tubers of a famous traditional Chinese herb-Ophiopogon japonicus Ker-Gawl. The spectroscopic and chemical data revealed their structures to be 3-tetradecyloxy-4-hydroxy-allylbenzene-4-O-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside (1), 3, 4-dihydroxy-allylbenzene-4-O-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside (2) and L-pyroglutamic acid (3). PMID:16350848

Dai, Hao Fu; Mei, Wen Li

2005-11-01

388

Two new furostanol glycosides from the fibrous root of Ophiopogon japonicus (Thunb.) Ker-Gawl.  

PubMed

Two new furostanol glycosides, ophiopogonins H (1) and I (2), were isolated from the fibrous root of Ophiopogon japonicus. The structures of 1 and 2 were established as (25R)-26-[(O-?-D-glucopyranosyl-(1?2)-?-D-glucopyranosyl)]-22?-hydroxyfurost-5-ene-3-O-[?-L-rhamnopyranosyl-(1?2)]-?-D-glucopyranoside and (25R)-26-[(O-?-D-glucopyranosyl-(1?2)-?-D-glucopyranosyl)]-20?-hydroxyfurost-5,22-diene-3-O-[?-L-rhamnopyranosyl-(1?2)]-?-D-glucopyranoside on the basis of spectroscopic means including HR-ESI-MS, 1D and 2D NMR experiments. PMID:20839120

Duan, Chang-Ling; Ma, Xiao-Feng; Jiang, Yong; Liu, Jian-Xun; Tu, Peng-Fei

2010-09-01

389

A novel steroidal glycoside, ophiofurospiside A from Ophiopogon japonicus (Thunb.) Ker-Gawl.  

PubMed

A new furospirostanol saponin, ophiofurospiside A (1), was isolated together with the known steroidal glycosides 2, 3, and 4 from the tubers of Ophiopogon japonicus (Thunb.) Ker-Gawl. Using chemical and spectral analyses (IR, MS, 1D NMR, and 2D NMR), the structure of 1 was established as 26-O-beta-d-glucopyranosyl-(22S, 25R)-furospirost-5-ene-3beta, 17alpha, 26-triol-3-O-[alpha-l-rhamnopyranosyl-(1 --> 2)]-[beta-d-xylopyranosyl-(1 --> 4)]-glucopyranoside (1). Three known steroidal saponins 2-4 were identified on the basis of spectroscopic data. PMID:18464079

Xu, Tun-Hai; Xu, Ya-Juan; Xie, Sheng-Xu; Zhao, Hong-Feng; Han, Dong; Li, Yu; Niu, Jian-Zhao; Xu, Dong-Ming

2008-01-01

390

Design and synthesis of nuclear localization sequence peptidomimetics utilizing glycoside scaffolding  

E-print Network

debenzylation yielding the tetra-aminopropyl glycosides 4a - 4e at a high level of purity (Scheme 2. 2). 's Scheme 2. 2 OH HO HO OMe OH 1a CN KOH(aq), DMF 40cC, 6 hr. OR RO RO OMe OR 2a R = CHzCHzCN 720/ 1. Hz, 600 psi, 70 C Raney cobalt, Hz... career path in synthetic organic I medicinal chemistry. TABLE OF CONTENTS ABSTRACT. DEDICATION. ACKNOWLEDGMENTS TABLE OF CONTENTS. LIST OF FIGURES LIST OF TABLES CHAPTER I INTRODUCTION AND BACKGROUND. 1. 1 Introduction. 1. 2 Background. 1. 3...

Schiller, Shawn Earle Richard

1999-01-01

391

Addition of electrophilic radicals to 2-benzyloxyglycals: synthesis and functionalization of fluorinated ?-C-glycosides and derivatives.  

PubMed

A new method for the synthesis of fluorinated ?-C-glycosides is described. The reactions between highly electrophilic radicals (fluorinated or unfluorinated) and a 2-benzyloxyglucal or galactal provide 2-keto-D-arabino- or 2-keto-D-lyxo-hexopyranosides through an addition/fragmentation process. Sodium borohydride mediated or Meerwein-Ponndorf-Verley (MPV) reduction of these compounds provides ?-C-glycosides that feature appropriate anchoring groups for further synthetic elaboration. The presence of CF2 CO2 iPr or CF2 Br groups at the pseudo-anomeric position allows efficient reduction/olefination or Br/Li-exchange/nucleophilic-addition sequences. These transformations open the way for the synthesis of fluorinated C-glycosidic analogues of glycoconjugates. PMID:23955898

Colombel, Sophie; Van Hijfte, Nathalie; Poisson, Thomas; Leclerc, Eric; Pannecoucke, Xavier

2013-09-16

392

Simultaneous separation and determination of four phenylethanoid glycosides in rat plasma sample after oral administration of Cistanche salsa extract by microemulsion liquid chromatography.  

PubMed

A simple, rapid and specific method was developed to separate as well as to determine the four phenylethanoid glycosides (PhGs) (echinacoside, tubuloside B, acteoside and isoacteoside) in rat plasma after oral administration of Cistanche salsa extract by reversed phase high performance liquid chromatography using a microemulsion as the mobile phase. The separations were performed on a Zorbax Extend-C18 column at 25°C. Photodiode-array detector was conducted at 322nm and with a flow rate of 0.8mLmin(-1). The optimized microemulsion mobile phase consisted of 0.3% triethylamine in 20mM phosphoric acid at pH 6.0, 0.8% (v/v) ethyl acetate as oil phase, 1.5% (v/v) Genapol X-080 as surfactant, 2.5% (v/v) n-propanol as co-surfactant. Under the optimal conditions, the calibration curve for four PhGs was linear in the range of 10-1000ngmL(-1) with the correlation coefficients greater than 0.9994. The intra-day and inter-day precision (RSD) were below 8.64% and the limits of detection (LOD) for the four PhGs were 0.4-1.3ngmL(-1) (S/N=3). The microemulsion liquid chromatography (MELC) method was successfully applied to separate and determine the four PhGs in rat plasma after oral administration of C. salsa extract. PMID:24508672

Zhou, Jun; Zhang, Qiong; Sun, Jiang Bing; Wang, Feng Qiao; Zeng, Ping

2014-03-01

393

Effects of hesperidin, a flavanone glycoside interaction on the conformation, stability, and aggregation of lysozyme: multispectroscopic and molecular dynamic simulation studies?  

PubMed

Hesperidin (HESP), a flavanone glycoside, shows high antioxidant properties and posses ability to go through the blood-brain barrier. Therefore, it could be a potential drug molecule against aggregation based diseases such as Alzheimer's, Parkinson's, and systemic amyloidoses. In this work, we investigated the potential of HESP to interact with hen egg-white lysozyme (HEWL) monomer and prevent its aggregation. The HESP-HEWL binding studies were performed using a fluorescence quenching technique, molecular docking and molecular dynamics simulations. We found a strong interaction of HESP with the lysozyme monomer (Ka, ~ 5 × 10(4) M(-1)) mainly through hydrogen bonding, water bridges, and hydrophobic interactions. We showed that HESP molecule spanned the highly aggregation prone region (amino acid residues 48-101) of HEWL and prevented its fibrillar aggregation. Further, we found that HESP binding completely inhibited amorphous aggregation of the protein induced by disulfide-reducing agent tries-(2-carboxyethyl) phosphine. Conformational and stability studies as followed by various tertiary and secondary structure probes revealed that HESP binding only marginally affected the lysozyme monomer conformation and increased both stability and reversibility of the protein against thermal denaturation. Future studies should investigate detail effects of HESP on solvent dynamics, structure, and toxicity of various aggregates. The answers to these questions will not only target the basic sciences, but also have application in biomedical and biotechnological sciences. PMID:25301518

Ratnaparkhi, Aditi; Muthu, Shivani A; Shiriskar, Sonali M; Pissurlenkar, Raghuvir R S; Choudhary, Sinjan; Ahmad, Basir

2014-11-01

394

Effect of harvest timing on leaf production and yield of diterpene glycosides in Stevia rebaudiana Bert: a specialty perennial crop for Mississippi  

Technology Transfer Automated Retrieval System (TEKTRAN)

Stevia rebaundiana (Bertoni), a perennial shrub of the Asteraceae, is one of the most important sources of non-caloric natural sweeteners. Stevia’s plant extracts and glycosides have been used for several years in Paraguay and Brazil. Several studies suggest that Stevia and its glycosides exert ben...

395

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

396

Comparison of chemical composition and free radical scavenging ability of glycosidically bound and free volatiles from Bosnian pine (Pinus heldreichii Christ. var. leucodermis).  

PubMed

The results obtained show that Bosnian pine is rich in glycosidically bound volatile compounds with strong free radical scavenging properties. Since volatiles can be released from nonvolatile glycoside precursors, these compounds can be considered as a hidden potential source of antioxidant substances and may contribute to the total free radical scavenging ability of Bosnian pine. PMID:17851386

Maric, Stanislava; Jukic, Mila; Katalinic, Visnja; Milos, Mladen

2007-01-01

397

Flavonoid Glycosides and Naphthodianthrones in the Sawfly Tenthredo zonula and its Host-Plants, Hypericum perforatum and H. hirsutum  

PubMed Central

Larvae of the sawfly Tenthredo zonula are specialized on Hypericum. Whether the sawfly is able to sequester plant metabolites was unknown. Aerial materials of Hypericum perforatum and H. hirsutum, as well as dissected larvae and prepupae of T. zonula, were analyzed by HPLC to determine the presence and content of flavonoid glycosides (rutin, hyperoside, isoquercitrin, and quercitrin) and naphthodianthrones (pseudohypericin and hypericin). All flavonoid glycosides were detected in both Hypericum species, with hyperoside as major compound in H. perforatum (ca. 1.7 ?mol/g fresh weight, FW) and isoquercitrin in H. hirsutum (0.7 ?mol/g FW). Naphthodianthrones were present at low concentrations (0.02 ?mol/g FW) in the former, and almost undetected in the latter species. In the body parts (i.e., hemolymph, digestive tract, salivary glands, or miscellaneous organs) of T. zonula, the surveyed compounds were detected more frequently in prepupae than in larvae. The compounds were not present in every sample, and flavonoid glycosides especially occurred in highly variable amounts, with maximal concentrations of 41 ?g rutin/prepupa in salivary glands, 8 ?g hyperoside/prepupa in hemolymph (= 0.36 ?mol/g FW), 32 ?g isoquercitrin/prepupa in salivary glands, and 63 ?g quercitrin/larva in miscellaneous organs (mainly composed of the integument). We conclude that flavonoid glycosides are sequestered since they were detected in organs other than the digestive tract of larvae, and because prepupae are a non-feeding stage. The naphthodianthrone pseudohypericin, but not hypericin, occurred generally in the digestive tract (up to 0.25 ?g/larva). Both naphthodianthrones and related unidentified compounds, but not flavonoid glycosides, were found in the larval excrement. The highly variable distributions of flavonoid glycosides and naphthodianthrones in T. zonula larvae and prepupae make it difficult to determine the ecological significance of these metabolites. PMID:21814831

2012-01-01

398

Anti-inflammatory activity and percutaneous absorption of quercetin and its polymethoxylated compound and glycosides: the relationships to chemical structures.  

PubMed

The potential of quercetin-related compounds for topical application has not previously been systematically investigated. To better elucidate relationships of the structure and activity with skin permeation, some quercetin compounds were used as permeants, including aglycone, a polymethoxylated compound (quercetin 3,5,7,3',4'-pentamethylether, QM), and seven glycosides. Quercetin and the glycoside with glucopyranuronic acid (Q4) at a dose of 30 ?M completely inhibited superoxide anion activated neutrophils. QM also potentially suppressed superoxide by 90%. Both quercetin and QM showed inhibitory activity on elastase release with respective IC(50) values of 6.25 and 15.76 ?M. Glycosylation significantly diminished this activity. Both an infinite concentration and saturated solubility in pH 7 buffer were used as permeant doses for the in vitro permeation experiments. The flux or permeability coefficient, which is the indicator for total absorption of dermal delivery due to the use of nude mouse skin, was the greatest for QM, followed by the glycosides and quercetin. QM showed 26× greater flux compared to quercetin. No penetration of quercetin occurred at the dose of saturated solubility. Rutin generally exhibited the highest skin permeation among the glycosides. It was found that the glycoside enantiomers (Q2 and Q3) revealed completely different permeation profiles. The stratum corneum was the principal penetration barrier for quercetin and its glycosides but not QM. Rutin provoked some skin redness and inflammation after a 5-day administration in nude mouse. QM caused no irritation, suggesting that it is a superior candidate for topical delivery. PMID:22609526

Lin, Chwan-Fwu; Leu, Yann-Lii; Al-Suwayeh, Saleh A; Ku, Ming-Chuan; Hwang, Tsong-Long; Fang, Jia-You

2012-12-18

399

Conformation of the glycosidic linkage in a disaccharide investigated by double-quantum solid-state NMR.  

PubMed

Double-quantum heteronuclear local field NMR is performed on a sample of a 13C2-labeled disaccharide, in which the two 13C spins are located on opposite sides of the glycosidic linkage. The evolution of the double-quantum coherences is found to be consistent with the solid-state conformation of the molecule, as previously determined by X-ray diffraction. The dependence of the double-quantum evolution on the glycosidic torsional angles is examined by using a graphical molecular manipulation program interfaced to a numerical spin simulation module. PMID:11444948

Ravindranathan, S; Karlsson, T; Lycknert, K; Widmalm, G; Levitt, M H

2001-07-01

400

Triterpene glycosides from the sea cucumber Eupentacta fraudatrix. Structure and biological activity of cucumariosides B1 and B2, two new minor non-sulfated unprecedented triosides.  

PubMed

Two new minor triterpene glycosides, cucumariosides B1 (1) and B2 (2) have been isolated from the Far Eastern sea cucumber Eupentacta fraudatrix. Structures of the glycosides were elucidated by 2D NMR spectroscopy and MS. Glycosides 1 and 2 belong to the cucumariosides B group and have unprecedented trisaccharide carbohydrate moieties without sulfate groups. Glycosides 1 and 2 differ from each other in side chain structures in the aglycone moieties. These minor substances are probably intermediate metabolites in the biosynthesis of triterpene pentaosides. Cytotoxic activities of glycosides 1 and 2 against mouse spleen lymphocytes and the cells of the ascite form of mouse Ehrlich carcinoma were studied, along with hemolytic activity against mouse erythrocytes and antifungal activity. Cucumarioside B1 (1) was not active in any of the tests, while cucumarioside B2 (2) demonstrated moderate hemolytic activity and low cytotoxic action against Ehrlich carcinoma cells. PMID:23074895

Silchenko, Alexandra S; Kalinovsky, Anatoly I; Avilov, Sergey A; Andryjaschenko, Pelageya V; Dmitrenok, Pavel S; Martyyas, Ekaterina A; Kalinin, Vladimir I

2012-09-01

401

Sequential Polarity-Reversing Circuit  

NASA Technical Reports Server (NTRS)

Proposed circuit reverses polarity of electric power supplied to bidirectional dc motor, reversible electro-mechanical actuator, or other device operating in direction depending on polarity. Circuit reverses polarity each time power turned on, without need for additional polarity-reversing or direction signals and circuitry to process them.

Labaw, Clayton C.

1994-01-01

402

Production of oleanolic acid glycosides by hairy root established cultures of Calendula officinalis L.  

PubMed

In order to initiate hairy root culture initiation cotyledons and hypocotyls of Calendula officinalis L. were infected with Agrobacterium rhizogenes strain ATCC 15834 or the same strain containing pCAMBIA 1381Z vector with ?-glucuronidase reporter gene under control of promoter of NIK (Nematode Induced Kinase) gene. The efficiency of induction of hairy roots reached 33.8% for cotyledons and 66.6% for hypocotyls together for both transformation experiments. Finally, eight control and nine modified lines were established as a long-term culture. The hairy root cultures showed the ability to synthesize oleanolic acid mainly (97%) as glycosides; control lines contained it at the average 8.42 mg ? g(-1) dry weight in tissue and 0.23 mg ? dm(-3) in medium; modified lines: 4.59 mg ? g(-1) for the tissue, and 0.48 mg ? dm(-3) for the medium. Additionally lines showed high positive correlation between dry/fresh weight and oleanolic acid concentration in tissue. Using the Killiani mixture in acidic hydrolysis of oleanolic acid glycosides released free aglycones that were partially acetylated in such conditions. PMID:24040627

D?ugosz, Marek; Wiktorowska, Ewa; Wi?niewska, Anita; P?czkowski, Cezary

2013-01-01

403

PARADOXICAL RESPONSES TO NEUROTOXIC STERYL GLYCOSIDES: INSIGHTS FROM A CELLULAR MODEL OF ALSPDC  

PubMed Central

The causes of many sporadic neurodegenerative diseases remain unknown making prevention difficult, if not impossible. One clue comes from the study of amyotrophic lateral sclerosis-parkinsonism dementia complex (ALS-PDC) of Guam which shares many similarities with amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease seen in other parts of the world. This disorder may provide a unique opportunity to study the cause and progression of neurodegenerative diseases. Epidemiological and experimental findings indicate that dietary consumption of cycad seeds is an underlying cause of ALS-PDC. Our laboratory provided evidence that a family of compounds called steryl glycosides are the active ingredients that may be responsible for producing the neurodegenerative outcome in ALS-PDC. Here, we review some of our work on the chronic toxicity of steryl glycosides in neuronal cells maintained in cell culture and in an in vivo mouse model. The current studies indicate some mechanisms about how neuronal cells respond to this class of toxins. PMID:21869879

Shaw, Christopher A.; Pelech, Steven; Ly, Philip T.T.

2010-01-01

404

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

PubMed Central

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. Small-subunit (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, ?10% were putative cellulases mostly 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 50°C 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. PMID:20098679

Allgaier, Martin; Reddy, Amitha; Park, Joshua I.; Ivanova, Natalia; D'haeseleer, Patrik; Lowry, Steve; Sapra, Rajat; Hazen, Terry C.; Simmons, Blake A.; VanderGheynst, Jean S.; Hugenholtz, Philip

2010-01-01

405

Production of a Novel Quercetin Glycoside through Metabolic Engineering of Escherichia coli  

PubMed Central

Most flavonoids exist as sugar conjugates. Naturally occurring flavonoid sugar conjugates include glucose, galactose, glucuronide, rhamnose, xylose, and arabinose. These flavonoid glycosides have diverse physiological activities, depending on the type of sugar attached. To synthesize an unnatural flavonoid glycoside, Actinobacillus actinomycetemcomitans gene tll (encoding dTDP-6-deoxy-l-lyxo-4-hexulose reductase, which converts the endogenous nucleotide sugar dTDP-4-dehydro-6-deoxy-l-mannose to dTDP-6-deoxytalose) was introduced into Escherichia coli. In addition, nucleotide-sugar dependent glycosyltransferases (UGTs) were screened to find a UGT that could use dTDP-6-deoxytalose. Supplementation of this engineered strain of E. coli with quercetin resulted in the production of quercetin-3-O-(6-deoxytalose). To increase the production of quercetin 3-O-(6-deoxytalose) by increasing the supplement of dTDP-6-deoxytalose in E. coli, we engineered nucleotide biosynthetic genes of E. coli, such as galU (UTP-glucose 1-phosphate uridyltransferase), rffA (dTDP-4-oxo-6-deoxy-d-glucose transaminase), and/or rfbD (dTDP-4-dehydrorahmnose reductase). The engineered E. coli strain produced approximately 98 mg of quercetin 3-O-(6-deoxytalose)/liter, which is 7-fold more than that produced by the wild-type strain, and the by-products, quercetin 3-O-glucose and quercetin 3-O-rhamnose, were also significantly reduced. PMID:22492444

Yoon, Jeong-A; Kim, Bong-Gyu; Lee, Woo Ju; Lim, Yoongho; Chong, Youhoon

2012-01-01

406

In vivo metabolism of Talosin A, new isoflavonol glycoside from Kitasatospora kifunensis, in rats  

PubMed Central

The isoflavonol glycoside Talosin A, genistein (GT)-7-?-L-6-deoxy talopyranose (GT-Tal), was first isolated from the culture broth of Kitasatospora kifunensis MJM341. The aim of the present study was to evaluate the oral absorption and metabolism of the newly isolated isoflavonol glycoside, GT-Tal compared to genistin (GT-7-O-?-D-glucopyranoside; GT-Glu). Free GT-Glu and GT-Tal could not be detected prior to enzymatic hydrolysis of the corresponding conjugates in rat plasma. Following oral administration of GT-Tal (15 min), GT-Tal was rapidly absorbed through the gastrointestinal tract and metabolized into GT-Tal conjugates with a mean Cmax of 2.74 µg/mL. GT-Tal was further metabolized to its aglycone, free GT and conjugated GT. After oral administration, GT-Glu was absorbed after being convereted to its aglycone and then further metabolized into its conjugate metabolites (free GT with a mean Cmax of 0.24 mg/mL at 1.25 h; conjugated GT with a mean Cmax of 1.31 mg/mL at 2.00 h). Significant differences in absorption and metabolism of GT-Tal and GT-Glu were observed. GT-Tal was metabolized into its corresponding conjugates or underwent deglycosylation to form GT, whereas GT-Glu was metabolized into its aglycone, GT. PMID:21586869

Lim, Jong-Hwan; Song, In-Bae; Hwang, Youn-Hwan; Kim, Myoung-Seok; Kim, Jong-Woo; Kim, Jin-Yong

2011-01-01

407

In vivo metabolism of Talosin A, new isoflavonol glycoside from Kitasatospora kifunensis, in rats.  

PubMed

The isoflavonol glycoside Talosin A, genistein (GT)-7-?-L-6-deoxy talopyranose (GT-Tal), was first isolated from the culture broth of Kitasatospora kifunensis MJM341. The aim of the present study was to evaluate the oral absorption and metabolism of the newly isolated isoflavonol glycoside, GT-Tal compared to genistin (GT-7-O-?-D-glucopyranoside; GT-Glu). Free GT-Glu and GT-Tal could not be detected prior to enzymatic hydrolysis of the corresponding conjugates in rat plasma. Following oral administration of GT-Tal (15 min), GT-Tal was rapidly absorbed through the gastrointestinal tract and metabolized into GT-Tal conjugates with a mean C(max) of 2.74 µg/mL. GT-Tal was further metabolized to its aglycone, free GT and conjugated GT. After oral administration, GT-Glu was absorbed after being converted to its aglycone and then further metabolized into its conjugate metabolites (free GT with a mean C(max) of 0.24 mg/mL at 1.25 h; conjugated GT with a mean C(max) of 1.31 mg/mL at 2.00 h). Significant differences in absorption and metabolism of GT-Tal and GT-Glu were observed. GT-Tal was metabolized into its corresponding conjugates or underwent deglycosylation to form GT, whereas GT-Glu was metabolized into its aglycone, GT. PMID:21586869

Lim, Jong-Hwan; Song, In-Bae; Hwang, Youn-Hwan; Kim, Myoung-Seok; Kim, Jong-Woo; Kim, Jin-Yong; Suh, Joo Won; Yun, Hyo-In

2011-06-01

408

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. Small-subunit (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, {approx}10% were putative cellulases mostly 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 50 C 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.

Allgaier, M.; Reddy, A.; Park, J. I.; Ivanova, N.; D'haeseleer, P.; Lowry, S.; Sapra, R.; Hazen, T.C.; Simmons, B.A.; VanderGheynst, J. S.; Hugenholtz, P.

2009-11-15

409

Discovery of selective small-molecule activators of a bacterial glycoside hydrolase.  

PubMed

Fragment-based approaches are used routinely to discover enzyme inhibitors as cellular tools and potential therapeutic agents. There have been few reports, however, of the discovery of small-molecule enzyme activators. Herein, we describe the discovery and characterization of small-molecule activators of a glycoside hydrolase (a bacterial O-GlcNAc hydrolase). A ligand-observed NMR screen of a library of commercially available fragments identified an enzyme activator which yielded an approximate 90?% increase in kcat /KM ?values (kcat =catalytic rate constant; KM =Michaelis constant). This compound binds to the enzyme in close proximity to the catalytic center. Evolution of the initial hits led to improved compounds that behave as nonessential activators effecting both KM ?and Vmax ?values (Vmax =maximum rate of reaction). The compounds appear to stabilize an active "closed" form of the enzyme. Such activators could offer an orthogonal alternative to enzyme inhibitors for perturbation of enzyme activity in?vivo, and could also be used for glycoside hydrolase activation in many industrial processes. PMID:25291993

Darby, John F; Landström, Jens; Roth, Christian; He, Yuan; Davies, Gideon J; Hubbard, Roderick E

2014-12-01

410

Pretreatment of baicalin and wogonoside with glycoside hydrolase: a promising approach to enhance anticancer potential.  

PubMed

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, 50?C, 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

2013-11-01

411

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

412

Identification, Quantification, and Sensory Characterization of Steviol Glycosides from Differently Processed Stevia rebaudiana Commercial Extracts.  

PubMed

Stevia rebaudiana is known for its sweet-tasting ent-kaurene diterpenoid glycosides. Several manufacturing strategies are currently employed to obtain Stevia sweeteners with the lowest possible off-flavors. The chemical composition of four commercial S. rebaudiana extracts, obtained by different technologies, was characterized using UHPLC-ESI-MS(n). The composition of one of the ethanol-crystallized extracts (EC2) was entirely rebaudioside A, whereas the enzymatically modified (EM) extract contained the lowest concentration of this compound (2.7 mg/100 mg). The membrane-purified (MP) extract had the highest content of minor natural steviol glycosides (23.7 mg/100 mg total extract) versus an average of 2.4 mg/100 mg total extract for the EC samples. Thirteen trained panelists evaluated sweetness, bitterness, licorice, and metallic attributes of all four extracts. The highest licorice intensity (p ? 0.05) was found for MP. Both samples EC1 and EC2, despite their different chemical compositions, showed no significant differences in sensory perception. PMID:25393842

Espinoza, María Inés; Vincken, Jean-Paul; Sanders, Mark; Castro, Cristian; Stieger, Markus; Agosin, Eduardo

2014-12-10

413

Two new flavonol glycosides from the Tibetan medicinal plant Aconitum tanguticum.  

PubMed

Two new flavonol glycosides characterized as quercetin 3-O-?-l-rhamnopyranosyl-(1 ? 2)-[?-d-glucopyranosyl-(1 ? 3)-?-l-(4-O-trans-p-coumaroylrhamnopyranosyl)-(1 ? 6)]-?-d-galactopyranoside-7-O-?-l-rhamnopyranoside (1) and kaempferol 3-O-?-l-rhamnopyranosyl-(1 ? 2)-[?-d-glucopyranosyl-(1 ? 3)-?-l-(4-O-trans-p-coumaroyl rhamnopyranosyl)-(1 ? 6)]-?-d-galactopyranoside-7-O-?-l-rhamnopyranoside (2), together with two known flavonol glycosides quercetin 3-O-?-l-rhamnopyranosyl-(1 ? 2)- [?-l-rhamnopyranosyl-(1 ? 6)]-?-d-galactopyranoside-7-O-?-l-rhamnopyranoside (3) and kaempferol 3-O-?-l-rhamnopyranosyl-(1 ? 2)-[?-l-rhamnopyranosyl-(1 ? 6)]-?-d-galactopyranoside-7-O-?-l-rhamnopyranoside (4), were isolated from the whole plant of Aconitum tanguticum (Maxim.) Stapf. The structures of the new compounds were elucidated by spectroscopic methods, and the total (1)H and (13)C NMR chemical shifts were assigned. PMID:23767974

Xu, Lu; Zhang, Xiao; Lin, Li-Mei; Li, Chun; Wang, Zhi-Min; Luo, Yong-Ming

2013-07-01

414

Changes in volatiles and glycosides during fruit maturation of two contrasted tomato ( Solanum lycopersicum ) lines.  

PubMed

The relationship between fruit maturation and volatile contents was investigated in two contrasted Cervil (CER) and Levovil (LEV) tomato ( Solanum lycopersicum ) lines. As fruits ripened, their volatile contents mainly increased. Although some compounds displayed contrasting patterns, overall, volatiles were clearly more abundant and conferred stronger aromas to CER than to LEV fruits. This intervarietal difference in volatile contents yielding much lower volatile contents in LEV was further investigated to determine whether it is due to a higher capacity of volatile glycosylation within LEV as compared to CER. Again, glycosides mainly increased during fruit maturation and were more abundant within CER than within LEV. Overall glycoside findings were indicative of a superior capacity to biosynthesize rather than an inferior capacity to glycosylate volatiles of CER. Eugenol and 2-methoxyphenol volatiles were exceptional compounds as they remained at higher levels in maturing LEV than in CER. 2-Methylthioacetaldehyde was for the first time identified as putatively related to differences of aroma between lines, as it was abundant in Cervil but absent in Levovil. Considering the described odor value of these three products, they should contribute differently to the particular olfactive features of LEV and CER fruits. PMID:19154163

Birti?, Simona; Ginies, Christian; Causse, Mathilde; Renard, Catherine M G C; Page, David

2009-01-28

415

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

416

Glycosides and amino acyl esters of carbohydrates as potent inhibitors of angiotensin converting enzyme.  

PubMed

About 12 glycosides prepared through amyloglucosidase catalysis and 23 amino acyl esters of carbohydrates prepared through lipase catalysis in organic solvents showed angiotensin converting enzyme (ACE) inhibition activity. Both amino acyl esters of carbohydrates and glycosides exhibited IC50 values for ACE inhibition in the 0.5 mM to 15.7 mM range. Eugenyl-D-glucoside (IC50: 0.5+/-0.04 mM), L-isoleucyl-D-glucose (IC50: 0.7+/-0.067 mM), vanillyl-D-sorbitol (IC50: 0.8+/-0.09 mM), L-histidyl-D-fructose (IC50: 0.9+/-0.087 mM), L-tryptophanyl-D-fructose (IC50: 0.9+/-0.092 mM), octyl-D-glucoside (IC50: 1.0+/-0.093 mM), vanillyl-D-mannoside (IC50: 1.0+/-0.089 mM), L-valyl-D-mannitol (IC50: 1.0+/-0.092 mM) and L-phenylalanyl-D-glucose (IC50: 1.0+/-0.089 mM) were the compounds, which showed the best ACE inhibitory activities. PMID:16730392

Lohith, K; Vijayakumar, G R; Somashekar, B R; Sivakumar, R; Divakar, S

2006-09-01

417

Differential Recognition and Hydrolysis of Host Carbohydrate Antigens by Streptococcus pneumoniae Family 98 Glycoside Hydrolases  

SciTech Connect

The presence of a fucose utilization operon in the Streptococcus pneumoniae genome and its established importance in virulence indicates a reliance of this bacterium on the harvesting of host fucose-containing glycans. The identities of these glycans, however, and how they are harvested is presently unknown. The biochemical and high resolution x-ray crystallographic analysis of two family 98 glycoside hydrolases (GH98s) from distinctive forms of the fucose utilization operon that originate from different S. pneumoniae strains reveal that one enzyme, the predominant type among pneumococcal isolates, has a unique endo-{beta}-galactosidase activity on the LewisY antigen. Altered active site topography in the other species of GH98 enzyme tune its endo-{beta}-galactosidase activity to the blood group A and B antigens. Despite their different specificities, these enzymes, and by extension all family 98 glycoside hydrolases, use an inverting catalytic mechanism. Many bacterial and viral pathogens exploit host carbohydrate antigens for adherence as a precursor to colonization or infection. However, this is the first evidence of bacterial endoglycosidase enzymes that are known to play a role in virulence and are specific for distinct host carbohydrate antigens. The strain-specific distribution of two distinct types of GH98 enzymes further suggests that S. pneumoniae strains may specialize to exploit host-specific antigens that vary from host to host, a factor that may feature in whether a strain is capable of colonizing a host or establishing an invasive infection.

Higgins, M.; Whitworth, G; El Warry, N; Randriantsoa, M; Samain, E; Burke, R; Vocadlo, D; Boraston, A

2009-01-01

418

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

419

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

420

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

421

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

422

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

423

Biosynthesis of (+)-catechin glycosides using recombinant amylosucrase from Deinococcus geothermalis DSM 11300.  

PubMed

Amylosucrase (ASase, EC 2.4.1.4) is a glucosyltransferase that hydrolyzes sucrose into glucose and fructose and produces amylose-like glucan polymers from the released glucose. (+)-Catechin is a plant polyphenolic metabolite having skin-whitening and antioxidant activities. In this study, the ASase gene from Deinococcus geothermalis (dgas) was expressed in Escherichia coli, while the recombinant DGAS enzyme was purified using a glutathione S-transferase fusion system. The (+)-catechin glycoside derivatives were synthesized from (+)-catechin using DGAS transglycosylation activity. We confirmed the presence of two major transglycosylation products using TLC. The (+)-catechin transglycosylation products were isolated using silica gel open column chromatography and recycling-HPLC. Two (+)-catechin major transfer products were determined through (1)H and (13)C NMR to be (+)-catechin-3'-O-?-D-glucopyranoside with a glucose molecule linked to (+)-catechin and (+)-catechin-3'-O-?-D-maltoside with a maltose linked to (+)-catechin. The presence of (+)-catechin maltooligosaccharides in the DGAS reaction was also confirmed via recycling-HPLC and enzymatic analysis. The effects of various reaction conditions (temperature, enzyme concentration, and molar ratio of acceptor and donor) on the yield and type of (+)-catechin glycosides were investigated. PMID:22112416

Cho, Hyun-Kug; Kim, Hee-Hang; Seo, Dong-Ho; Jung, Jong-Hyun; Park, Ji-Hae; Baek, Nam-In; Kim, Myo-Jeong; Yoo, Sang-Ho; Cha, Jaeho; Kim, Young-Rok; Park, Cheon-Seok

2011-07-10

424

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

PubMed

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

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

2001-06-01

425

Structural Elucidation of Dextran Degradation Mechanism by Streptococcus mutans Dextranase Belonging to Glycoside Hydrolase Family 66*  

PubMed Central

Dextranase is an enzyme that hydrolyzes dextran ?-1,6 linkages. Streptococcus mutans dextranase belongs to glycoside hydrolase family 66, producing isomaltooligosaccharides of various sizes and consisting of at least five amino acid sequence regions. The crystal structure of the conserved fragment from Gln100 to Ile732 of S. mutans dextranase, devoid of its N- and C-terminal variable regions, was determined at 1.6 Å resolution and found to contain three structural domains. Domain N possessed an immunoglobulin-like ?-sandwich fold; domain A contained the enzyme's catalytic module, comprising a (?/?)8-barrel; and domain C formed a ?-sandwich structure containing two Greek key motifs. Two ligand complex structures were also determined, and, in the enzyme-isomaltotriose complex structure, the bound isomaltooligosaccharide with four glucose moieties was observed in the catalytic glycone cleft and considered to be the transglycosylation product of the enzyme, indicating the presence of four subsites, ?4 to ?1, in the catalytic cleft. The complexed structure with 4?,5?-epoxypentyl-?-d-glucopyranoside, a suicide substrate of the enzyme, revealed that the epoxide ring reacted to form a covalent bond with the Asp385 side chain. These structures collectively indicated that Asp385 was the catalytic nucleophile and that Glu453 was the acid/base of the double displacement mechanism, in which the enzyme showed a retaining catalytic character. This is the first structural report for the enzyme belonging to glycoside hydrolase family 66, elucidating the enzyme's catalytic machinery. PMID:22337884

Suzuki, Nobuhiro; Kim, Young-Min; Fujimoto, Zui; Momma, Mitsuru; Okuyama, Masayuki; Mori, Haruhide; Funane, Kazumi; Kimura, Atsuo

2012-01-01

426

Comparative analysis of glycoside hydrolases activities from phylogenetically diverse marine bacteria of the genus Arenibacter.  

PubMed

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

2013-06-01

427

Expression and crystallization of a bacterial glycoside hydrolase family 116 ?-glucosidase from Thermoanaerobacterium xylanolyticum.  

PubMed

The Thermoanaerobacterium xylanolyticum gene product TxGH116, a glycoside hydrolase family 116 protein of 806 amino-acid residues sharing 37% amino-acid sequence identity over 783 residues with human glucosylceramidase 2 (GBA2), was expressed in Escherichia coli. Purification by heating, immobilized metal-affinity and size-exclusion chromatography produced >90% pure TxGH116 protein with an apparent molecular mass of 90?kDa on SDS-PAGE. The purified TxGH116 enzyme hydrolyzed the p-nitrophenyl (pNP) glycosides pNP-?-D-glucoside, pNP-?-D-galactoside and pNP-N-acetyl-?-D-glucopyranoside, as well as cellobiose and cellotriose. The TxGH116 protein was crystallized using a precipitant consisting of 0.6?M sodium citrate tribasic, 0.1?M Tris-HCl pH 7.0 by vapour diffusion with micro-seeding to form crystals with maximum dimensions of 120 × 25 × 5?µm. The TxGH116 crystals diffracted X-rays to 3.15?Å resolution and belonged to the monoclinic space group P21. Structure solution will allow a structural explanation of the effects of human GBA2 mutations. PMID:25615966

Sansenya, Sompong; Mutoh, Risa; Charoenwattanasatien, Ratana; Kurisu, Genji; Ketudat Cairns, James R

2015-01-01

428

Reversible Chemical Kinetics Model  

NSDL National Science Digital Library

The Reversible Chemical Kinetics Model illustrates the time evolution of a reversible chemical reaction, from a given set of initial reactants concentration until chemical equilibrium is reached. The concentrations are plotted against time and the respective numerical values are periodically displayed at the data Table. As chemical equilibrium is attained, the concentrations become constant, the reaction quotient (Q) equalizes the equilibrium constant and Gibbs's energy change (G/RT) approaches zero. The Reversible Chemical Kinetics Model was developed using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the jar file will run the program if Java is installed. You can modify this simulation if you have EJS installed by right-clicking within the map and selecting "Open Ejs Model" from the pop-up menu item.

Fernandes, Fernando S.

2012-10-20

429

Dynamics of magnetization reversal  

NASA Astrophysics Data System (ADS)

Advanced magnetic recording systems are designed for extremely high areal densities and data rate. These two aspects require both magnetization reversal at very short times (< 1 ns) and long term ( ~ 5-10 years) stability against thermal fluctuations. There are two basic physics problems associated with these requirements. The first is a characterization of thermal-dynamic reversal over very wide time range. The second is an understanding of the physics of the relaxation mechanisms. Both these subjects will be reviewed in this talk. Thermal dynamic reversal requires solution of the Landau-Lifshitz equation with fluctuations. We have solved this problem in terms of the ``random walk" dynamics of a nonlinear oscillator [1,2]. The expressions for the switching field versus pulse time are analytic and show good agreement with measurements on CrO_2. Our studies of fundamental relaxation mechanisms have involved a two step approach. First the results of computer simulations of magnetization reversal without phenomenological damping will be discussed. In this case coherent rotation of the magnetization excites spin waves during which an excess of Zeeman energy is transformed to anisotropy and exchange energies. However, for fine grains whose size is sufficiently small so that the grain magnetization is virtually uniform, non-linear spin waves cannot assist reversal [3]. A new analytic model of reversal that couples coherent rotation to impurity ions by an anisotropic exchange mechanism will be discussed. These impurity ions are assumed to relax at a very high rate to the lattice. [1] V.L.Safonov, JMMM 195, 523 (1999); J.Appl.Phys. 85, 4370 (1999). [2] V.L.Safonov, H.N.Bertram, MMM'99, CU-09. [3] V.L.Safonov, H.N.Bertram, J.Appl.Phys. 85, 5072 (1999); MMM'99, CD-11.

Safonov, Vladimir L.

2000-03-01

430

Reverse Cholesterol Transport  

Microsoft Academic Search

Atherosclerosis, the accumulation of cholesterol in the arteries resulting in heart attacks and strokes, is the leading cause of death in the USA and most other industrialized countries in the world. Plasma levels of high-density lipoprotein (HDL) cholesterol are invariably found to be inversely associated with the risk of atherosclerosis. This protective effect has classically been ascribed to HDL-mediated reverse

Jim Burgess; P HILIP A. SINCLAIR; Christophe Chretien; Jonathon Boucher; DANIEL L. SPARKS

431

Reversible Thermoelectric Nanomaterials  

Microsoft Academic Search

Irreversible effects in thermoelectric materials limit their efficiency and economy for applications in power generation and refrigeration. While electron transport is unavoidably irreversible in bulk materials, here we derive conditions under which reversible diffusive electron transport can be achieved in nanostructured thermoelectric materials. We provide a fundamental thermodynamic explanation for why the optimum density of states in a thermoelectric material

T. E. Humphrey; H. Linke

2005-01-01

432

Time reversal communication system  

DOEpatents

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

433

[Carotinoid retinopathy. III. Reversibility].  

PubMed

Twenty-five patients (erythropoietic protoporphyria 23, polymorphous light eruption 1, "cosmetics" 1) were re-examined 2-10 months after therapy with beta-carotene and canthaxanthine was discontinued. Dark adaptation and ERG parameters had normalized, whereas crystalline retinopathy and pigment epithelial defects showed no signs of reversibility. PMID:3959472

Weber, U; Goerz, G

1986-01-01

434

Reversible Barrel Shifters  

Microsoft Academic Search

Data shifting is required in many key computer operations from address decoding to computer arithmetic. Full barrel shifters are often on the critical path, which has led most research to be directed toward speed optimizations. With the advent of quantum computer and reversible logic, design and implementation of all devices in this logic has received more attention. This paper proposes

Saeid Gorgin; Amir Kaivani

2007-01-01

435

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

436

Unlike Quercetin Glycosides, Cyanidin Glycoside in Red Leaf Lettuce Responds More Sensitively to Increasing Low Radiation Intensity before than after Head Formation Has Started  

PubMed Central

This study investigated the effect of low-level photosynthetic photon flux density (PPFD; 43–230 ?mol m–2 s–1) on the major phenolic compounds of red leaf lettuce in three growth stages, before, during, and after head formation, using HPLC-DAD-ESI-MS2 and evaluating via multiple regression analysis. Generally, the light-related increase of flavonoid glycosides was structure and growth stage-dependent. In detail, an interaction was detected between plant age and PPFD regarding cyanidin-3-O-(6?-O-malonyl)-glucoside concentration: the increase was strongest before head formation. The relationship between PPFD and quercetin-3-O-(6?-O-malonyl)-glucoside concentration was linear, whereas the increase of quercetin-3-O-glucoside and -3-O-glucuronide concentrations abated with increasing PPFD. Independent of growth stage, the caffeic acid derivatives concentration was not related to PPFD. All major phenolic compounds decreased with plant age. These results show the differential regulation of cyanidin, quercetin, and caffeic acid derivatives in lettuce, although closely connected biosynthetically, and emphasize the importance of ontogeny in the study of plant physiology. PMID:24382136

2014-01-01

437

Studies on the constituents of Tinospora sinensis; I. Separation and structure of the new phenolic glycoside tinosinen.  

PubMed

A new phenolic glycoside, tinosinen (1), was isolated from the fresh stems of Tinospora sinensis Merr. The structure was established on the basis of acid hydrolysis and spectral data (IR, NMR, mass) as (E)-1-(3-hydroxy-1-propenyl)-3,5-dimethoxyphenyl 4-O-beta-D-apiofuranosyl-(1-->3)-beta-D-glucopyranoside. PMID:8302956

Yonemitsu, M; Fukuda, N; Kimura, T

1993-12-01

438

The functions of steryl glycosides come to those who wait: Recent advances in plants, fungi, bacteria and animals  

Microsoft Academic Search

The attachment of a sugar moiety to the 3-hydroxy group of a sterol drastically increases the size of the hydrophilic part of the lipid. It is obvious that the glycosylation of a considerable fraction of membrane-bound free sterols alters the biophysical properties of the membrane. However, the consequences of such changes in the proportions of free sterols and steryl glycosides

Sandra Grille; Anna Zaslawski; Swantje Thiele; Jogchum Plat; Dirk Warnecke

2010-01-01

439

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 that O3 scavenging by direct reactions with reduced AA was very limited. In regard to phenolics, O3 of sinapoyl malate. However, modelling of O3 scavenging in the apoplast indicated that sinapoyl malate

Jones, Alan M.

440

Biochem. J. (1989) 262, 541-548 (Printed in Great Britain) Kinetic analysis of the interaction of alkyl glycosides  

E-print Network

substrates. INTRODUCTION Human visceral organs such as liver, spleen and kidney contain two prominent ,JBiochem. J. (1989) 262, 541-548 (Printed in Great Britain) Kinetic analysis of the interaction of alkyl glycosides with two human fl-glucosidases Venkatakrishnan GOPALAN,* Lydia B. DANIELS,* Robert H

Gopalan, Venkat

441

Validation of HPLC-UV method for determination of minor glycosides contained in Stevia rebaudiana Bertoni leaves.  

PubMed

Leaves of Stevia rebaudiana contain glycosides with sweetness and biological activity. However besides the major glycosides, there are other glycosides within extracts that may contribute to its activity, and therefore it is important to quantify them. In this work, an isocratic HPLC method was validated for determination of dulcoside A, steviolbioside, rebaudioside C and rebaudioside B. An HPLC method was performed using a C18 column (250?×?4.6?mm, particle size 5?µm) and a UV detector set at 210?nm. The mobile phase consisted of a 32:68 (v/v) mixture of acetonitrile and sodium phosphate buffer (10?mmol/L, pH?2.6), set to a flow rate of 1.0?mL/min. The calculated parameters were: sensitivity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy and precision. The calibration curves were linear over the working range 25-150?µg/mL, with coefficient of correlation of ?0.99 and coefficient of determination of ?0.98. The LOD was 5.68-8.81?µg/mL, while the LOQ was 17.21-26.69?µg/mL. The percentage recoveries of fortified samples were 100?±?10% and precision, relative standard deviation, was <10%. The method validation showed accuracy, linearity and precision; therefore this method can be applied for quantitative analysis of minor steviol glycosides in S. rebaudiana leaves. Copyright © 2014 John Wiley & Sons, Ltd. PMID:25296637

Aranda-González, Irma; Moguel-Ordoñez, Yolanda; Betancur-Ancona, David

2014-10-01

442

INFLUENCE OF GLYCOSIDIC LINKAGES AND MOLECULAR WEIGHT ON THE FERMENTATION OF MALTOSE-BASED OLIGOSACCHARIDES BY GUT BACTERIA  

Technology Transfer Automated Retrieval System (TEKTRAN)

A structure-function study was carried out to increase knowledge of how glycosidic linkages and molecular weight of carbohydrates contribute towards the selectivity of fermentation by gut bacteria. Oligosaccharides with maltose as the common carbohydrate source were used. Potentially prebiotic alt...

443

Protective effects of flavonols and their glycosides against free radical-induced oxidative hemolysis of red blood cells  

Microsoft Academic Search

The in vitro oxidative hemolysis of human red blood cells (RBCs) was used as a model to study the free radical-induced damage of biological membranes and the protective effect of flavonols and their glycosides (FOHs), i.e., myricetin (MY), quercetin (Q), morin (MO), kaempferol (K), rutin (R), quercetin galactopyranoside (QG), quercetin rhamnopyranoside (QR), and kaempferol glucopyranoside (KG). The hemolysis of RBCs

Fang Dai; Qing Miao; Bo Zhou; Li Yang; Zhong-Li Liu

2006-01-01

444

Evaluation of anti-HIV-1 activity of a new iridoid glycoside isolated from Avicenna marina, in vitro.  

PubMed

This study was carried out to check the efficacy of methanol seed extract of Avicenna marina and its column chromatographic fractions on Peripheral Blood Mono nuclear Cells (PBMCs) toxicity and HIV-1 replication. The anti-HIV-1 activities of crude methanol extract and its fractions were performed by use of real-time polymerase chain reaction (PCR) assay and HIV-1 p24 antigen kit. A time of drug addiction approach was also done to identify target of anti-HIV compound. The activity of the extracts on CD4, CD3, CD19 and CD45 expression in lymphocytes population was performed by use of flow cytometry. The most active anti-HIV agent was detected by spectroscopic analysis as 2'-O-(4-methoxycinnamoyl) mussaenosidic acid. The apparent effective concentrations for 50% virus replication (EC50) of methanol extract and iridoid glycoside were 45 and 0.1?g/ml respectively. The iridoid glycoside also did not have any observable effect on the proportion of CD4, CD3, CD19 and CD45 cells or on the intensity of their expressions on PBMCs. In addition, the expression level of C-C chemokine receptor type 5 (CCR5) and chemokine receptor type 4 (CXCR4) on CD4(+) T cells were decreased in cells treated with this iridoid glycoside. The reduction of these two HIV coreceptors and the result of time of addition study demonstrated that this iridoid glycoside restricts HIV-1 replication on the early stage of HIV infection. PMID:25239814

Behbahani, Mandana

2014-09-16

445

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

446

Substrate Specificity in Glycoside Hydrolase Family 10 STRUCTURAL AND KINETIC ANALYSIS OF THE STREPTOMYCES LIVIDANS XYLANASE 10A*  

E-print Network

OF THE STREPTOMYCES LIVIDANS XYLANASE 10A* Received for publication, January 7, 2000, and in revised form, March 24. The Streptomyces lividans xylanase Xyl10A is a family 10 enzyme, the native structure of which has previously been, shed new light on substrate specificity in glycoside hydrolase family 10. Endo-xylanases (EC 3

447

A general approach to quantification of hydroxycinnamic acid derivatives and flavones, flavonols, and their glycosides by UV spectrophotometry  

Technology Transfer Automated Retrieval System (TEKTRAN)

A general method was developed for the quantification of hydroxycinnamic acid derivatives and flavones, flavonols, and their glycosides based on the UV molar relative response factors (MRRF) of the standards. Each of these phenolic compounds contains a cinnamoyl structure and has a maximum absorban...

448

Purification and characterization of a glycoside hydrolase family 43 Beta-xylosidase from Geobacillus thermoleovorans IT-08  

Technology Transfer Automated Retrieval System (TEKTRAN)

The gene encoding a glycoside hydrolase family 43 enzyme termed deAX was isolated and subcloned from a culture seeded with a compost starter mixed bacterium population, expressed with a C-terminal His6-tag, and purified to apparent homogeneity. deAX was monomeric in solution, and had a broad pH maxi...

449

2724 J. Org. Chem. 1994,59, 2724-2728 Boronic Acids Mediate Glycoside Transport through a Liquid  

E-print Network

2724 J. Org. Chem. 1994,59, 2724-2728 Boronic Acids Mediate Glycoside Transport through a Liquid of Notre Dame, Notre Dame, Indiana 46556 Received December 29, 1993 The ability of phenylboronic acid and 3-xylopyranoside (xyloside) through a liquid dichloroethane membrane in the presence and absence of trioctyl- methylammonium

Smith, Bradley D.

450

Enzymatic synthesis of L-DOPA alpha-glycosides by reaction with sucrose catalyzed by four different glucansucrases from four strains of Leuconostoc mesenteroides.  

PubMed

L-DOPA alpha-glycosides were synthesized by reaction of L-DOPA with sucrose, catalyzed by four different glucansucrases from Leuconostoc mesenteroides B-512FMC, B-742CB, B-1299A, and B-1355C. The glucansucrases catalyzed the transfer of d-glucose from sucrose to the phenolic hydroxyl position-3 and -4 of L-DOPA. The glycosides were fractionated and purified by Bio-Gel P-2 column chromatography, and the structures were determined by (1)H NMR spectroscopy. The major glycoside was 4-O-alpha-d-glucopyranosyl L-DOPA, and the minor glycoside was 3-O-alpha-D-glucopyranosyl L-DOPA. The two glycosides were formed by all four of the glucansucrases. The ratio of the 4-O-alpha-glycoside to the 3-O-alpha-glycoside produced by the B-512FMC dextransucrase was higher than that for the other three glucansucrases. The glycosylation of L-DOPA significantly reduced the oxidation of the phenolic hydroxyl groups, which prevents their methylation, potentially increasing the use of L-DOPA in the treatment of Parkinson's disease. The use of one enzyme, glucansucrase, and sucrose as the D-glucosyl donor makes the synthesis considerably simpler and cheaper than the formerly published procedure using cyclomaltodextrin and cyclomaltodextrin glucanyltransferase, followed by glucoamylase, and beta-amylase hydrolysis. PMID:20579635

Yoon, Seung-Heon; Fulton, D Bruce; Robyt, John F

2010-08-16

451

Flavonoid glycosides from Chromolaena odorata leaves and their in vitro cytotoxic activity.  

PubMed

Two new flavonoid glycosides, (1, 2), and eleven known compounds, (3-13), were isolated from from a 70% EtOH extract of the leaves of Chromolaena odorata (Asteraceae). Their structures were elucidated by 1D and 2D NMR spectroscopic interpretation as well as by chemical studies. The newly isolated compounds were tested in vitro for their cytotoxic activities against the LLC and HL-60 cancer cell lines. Compound 1 showed cytotoxicity against LLC and HL-60 cancer cell lines with IC(50) values of 28.2 and 11.6 µM, respectively. Compound 2 exhibited significant cytotoxic activity in the inhibition of HL-60 cancer cell lines with IC(50) value of 10.8 µM. PMID:21212562

Hung, Tran Manh; Cuong, To Dao; Dang, Nguyen Hai; Zhu, Shu; Long, Pham Quoc; Komatsu, Katsuko; Min, Byung Sun

2011-01-01

452

Potent airway smooth muscle relaxant effect of cynatratoside B, a steroidal glycoside isolated from Cynanchum stauntonii.  

PubMed

The dried roots of Cynanchum stauntonii in having cough-relieving efficacy are commonly included in traditional antitussive formulas. The active components in a C. stauntonii root extract responsible for airway relaxation were isolated using an ex vivo bioassay-guided fractionation method, in which subfractions were evaluated for their inhibitory effects on the contraction of isolated rat tracheal rings by isometric tension measurements. A steroidal glycoside, cynatratoside B (1), identified by LC-MS and NMR spectroscopic analysis, was shown to have potent inhibition on acetylcholine- and carbachol-induced tracheal contractions. The present data provide scientific evidence to support the traditional use of C. stauntonii as an antitussive herbal medicine. PMID:24761833

Yue, Grace Gar-Lee; Chan, Kar-Man; To, Ming-Ho; Cheng, Ling; Fung, Kwok-Pui; Leung, Ping-Chung; Lau, Clara Bik-San

2014-04-25

453

Additional antiprotozoal flavonol glycosides of the aerial parts of Helianthemum glomeratum.  

PubMed

Bioassay-guided fractionation of the methanol extract of aerial parts from Helianthemum glomeratum afforded five antiprotozoal flavonol glycosides: tiliroside, kaempferol-3-O-(3'',6''di-O-E-p-coumaroyl)-betad-glucopyranoside, astragalin, quercitrin and isoquercitrin. The in vitro antiprotozoal assay showed that tiliroside was the most potent antiamoebic and antigiardial compound with IC(50) values of 17.5 microg/mL for Entamoeba histolytica and 17.4 microg/mL for G. lamblia. Isoquercitrin showed selectivity against E. histolytica (IC(50) 14.7 microg/mL) and quercitrin toward G. lamblia (IC(50) 24.3 microg/mL). All isolated compounds were less active than metronidazole and emetine, two antiprotozoal drugs used as positive controls. PMID:17094176

Calzada, Fernando; Alanís, Alma Delia

2007-01-01

454

Neuroprotective benzyl benzoate glycosides from Disporum viridescens roots in HT22 hippocampal neuronal cells.  

PubMed

Bioassay-guided fractionation of the EtOAc extract from Disporum viridescens roots led to the isolation of five new benzyl benzoate glycosides, BBGs (1-5). The neuroprotective activities of the BBGs were screened using neuronal HT22 hippocampal cells. BBG-D (4) significantly protected murine hippocampal HT22 cells against glutamate-induced neurotoxicity by maintaining the antioxidative defense systems such as superoxide dismutase, glutathione reductase, glutathione peroxidase, and the glutathione content. BBG-D, in a dose-and time-dependent manner, increased HO-1 expression through the selective activation of pERK signaling among the MAPK pathways. These results suggest that BBG-D could be a promising candidate for the treatment of neurodegenerative diseases related to glutamate-induced oxidative neuronal cytotoxicity. PMID:24246008

Cho, Namki; Yang, Heejung; Lee, Mina; Huh, Jungmoo; Kim, Hyeon-Woo; Kim, Hong-Pyo; Sung, Sang-Hyun

2013-12-27

455

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, Maurício R. V.; Dillon, Rod J.; Genta, Fernando A.

2014-01-01

456

Cycloartane-type triterpene glycosides from the rhizomes of Cimicifuga heracleifolia and their anticomplementary activity.  

PubMed

Seven known triterpene glycosides, 23-O-acetylshengmanol 3-O-?-L-arabinopyranoside (1), 23-O-acetylshengmanol 3-O-?-D-xylopyranoside (2), 24-epi-24-O-acetylhydroshengmanol 3-O-?-D-xylopyranoside (3), cimiaceroside B (4), (23R,24S)-cimigenol 3-O-?-D-xylopyranoside (5), (23R,24R)-25-O-acetylcimigenol 3-O-?-D-xylopyranoside (6) and (23R,24S)-25-O-anhydrocimigenol 3-O-?-D-xylopyranoside (7) were isolated from the rhizomes of Cimicifuga heracleifolia. Their chemical structures were determined on the basis of spectroscopic analyses including 2D NMR. All isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 6 showed strong inhibitory activity with an IC?? value of 7.7 µM while compound 3 was moderately active with an IC?? value of 195.6 µM. PMID:22753039

Lee, Jung Hoon; Cuong, To Dao; Kwack, Seung Jun; Seok, Ji Hyeon; Lee, Jong Kwon; Jeong, Ja Young; Woo, Mi-Hee; Choi, Jae Sue; Lee, Hyeong Kyu; Min, Byung Sun

2012-08-01

457

Studies on the phenylethanoid glycosides with anti-complement activity from Paulownia tomentosa var. tomentosa wood.  

PubMed

Four epimeric phenylethanoid glycosides, including a new one, R,S-beta-ethoxy-beta-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl(1-->3)-beta-D-(6-O-E-caffeoyl)-glucopyranoside named isoilicifolioside A (1), and three known compounds, ilicifolioside A (2), campneoside II (3), and isocampneoside II (4), were isolated from Paulownia tomentosa var. tomentosa wood. The structures of the four compounds were elucidated by the interpretation of 1D and 2D NMR and MS spectra. This is the first report of the chemical profile of this tree. Compounds 1-4 exhibited excellent anti-complement activity with IC(50) values less than 74 microM, compared with tiliroside (IC(50) = 104 microM) and rosmarinic acid (IC(50) = 182 microM) that were used as positive controls. PMID:19031237

Si, Chuan-Ling; Deng, Xiao-Juan; Liu, Zhong; Kim, Jin-Kyu; Bae, Young-Soo

2008-01-01

458

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

PubMed

A method is described for determining the duration of action of cardiac glycosides and aglycones in the guinea-pig. It is based on their property of potentiating the cardiac response to adenosine. The method is particularly suitable for those drugs with a short duration of action, whereas previous methods are more suitable for those drugs with longer durations of action. The duration of action of one-fifth of the lethal dose has been found for: digoxigenin, lanatoside C, ouabain, digitoxigenin-3-one, digitoxin, 3-acetyldigitoxigenin, digoxin, digitoxigenin, lanatoside A; these drugs are arranged in order of increasing duration of action. The possible relationship between the elimination of these drugs and their duration of action can provide an estimate of their rates of elimination. PMID:13662569

RAND, M; STAFFORD, A

1959-06-01

459

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

PubMed Central

A method is described for determining the duration of action of cardiac glycosides and aglycones in the guinea-pig. It is based on their property of potentiating the cardiac response to adenosine. The method is particularly suitable for those drugs with a short duration of action, whereas previous methods are more suitable for those drugs with longer durations of action. The duration of action of one-fifth of the lethal dose has been found for: digoxigenin, lanatoside C, ouabain, digitoxigenin-3-one, digitoxin, 3-acetyldigitoxigenin, digoxin, digitoxigenin, lanatoside A; these drugs are arranged in order of increasing duration of action. The possible relationship between the elimination of these drugs and their duration of action can provide an estimate of their rates of elimination. PMID:13662569

Rand, M.; Stafford, Anne

1959-01-01

460

New chalcanonol glycoside from the seeds of saw palmetto: antiproliferative and antioxidant effects.  

PubMed

A new chalcanonol glycoside dimer, bis-O-[(I-4') ? (II-6')]-?-hydroxyphloretin-2'-O-?-glucoside (1), in addition to six known compounds, namely ( - )-epicatechin (2) and ( - )-epiafzelechin (3), 4-hydroxybenzoic acid (4), protocatechuic acid (5), methylgallate (6), ?-sitosterol (7) and ?-sitosterol-3-O-glucoside (8), was isolated from the seeds of saw palmetto. The structures of the isolated compounds were established from the analysis of their MS and 1D and 2D NMR spectroscopic data. The antiproliferative activities of the isolated compounds towards PC3, the human prostate cancer cells were investigated. Amongst the isolated compounds, the new compound and the sterolic derivatives showed antiproliferative effects. Screening of the antioxidant effects of the isolated compounds by 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid radical assay revealed that the isolated phenolics were active free radical scavengers. PMID:25230777

Abdel Bar, Fatma M

2014-09-18

461

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

462

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

463

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

464

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

465

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

466

Local site selectivity and conformational structures in the glycosidic bond scission of cellobiose.  

PubMed

Car-Parrinello molecular dynamics combined with metadynamics simulations were used to study the acid-catalyzed hydrolysis of cellobiose (CB) in aqueous solution. The hydrolysis was studied in two steps. Step 1 involves the proton transfer from solvent to CB and dissociation of the glycosidic bond to ?-glucose and oxacarbenium ion species. Step 2 involves the formation of ?-glucose from oxacarbenium and regeneration of the acid proton species. Step 1 is endothermic, while Step 2 is exothermic. The overall activation free energy of CB hydrolysis is 32.5 kcal mol(-1), and the overall reaction free energy is -5.9 kcal mol(-l), consistent with available experimental data. We observe that a stepwise mechanism generally described in the literature for Step 1 is not significantly favored relative to a concerted ?-1,4' linkage dissociation process. PMID:21800820

Liang, Xiao; Montoya, Alejandro; Haynes, Brian S

2011-09-15

467

Paeoniflorin, a monoterpene glycoside, attenuates lipopolysaccharide-induced neuronal injury and brain microglial inflammatory response.  

PubMed

Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Paeoniflorin (PF), a water-soluble monoterpene glycoside found in the root of Paeonia lactiflora Pall, has a wide range of pharmacological functions, such as anti-oxidant, anti-inflammatory, and anti-cancer effects. Neuroprotective potential of PF has also been demonstrated in animal models of neuropathologies. Here, we have examined the efficacy of PF in the repression of inflammation-induced neurotoxicity and microglial inflammatory response. In organotypic hippocampal slice cultures, PF significantly blocked lipopolysaccharide (LPS)-induced hippocampal cell death and productions of nitric oxide (NO) and interleukin (IL)-1?. PF also inhibited the LPS-stimulated productions of NO, tumor necrosis factor-?, and IL-1? from primary microglial cells. These results suggest that PF possesses neuroprotective activity by reducing the production of proinflammatory factors from activated microglial cells. PMID:23559368

Nam, Kyong-Nyon; Yae, Che Gyem; Hong, Joung-Woo; Cho, Dong-Hyung; Lee, Joon H; Lee, Eunjoo H

2013-08-01

468

cis-Eudesmane sesquiterpene glycosides from Liriope muscari and Ophiopogon japonicus.  

PubMed

Two new cis-eudesmane sesquiterpene glycosides, liriopeoside A (1) and ophiopogonoside A (2), were extracted and purified from tubers of Liriope muscari and Ophiopogon japonicus, respectively, along with three known compounds. Their structures were elucidated as 1beta,6beta-dihydroxy-cis-eudesm-3-ene-6-O-beta-D-glucopyranoside (1) and 1beta,4beta,6beta-trihydroxy-cis-eudesmane-6-O-beta-D-glucopyranoside (2) by spectral data analysis. The structure and the relative configuration of compound 1 were confirmed by X-ray crystallographic analysis. This is the first time that cis-eudesmane-type sesquiterpenes have been reported from the genera Ophiopogon and Liriope. PMID:15497959

Cheng, Zhi-Hong; Wu, Tao; Bligh, S W Annie; Bashall, Alan; Yu, Bo-Yang

2004-10-01

469

Characterisation of free and glycosidically bound aroma compounds of La Mancha Verdejo white wines.  

PubMed

The aroma of Verdejo La Mancha white wines was studied by instrumental and sensory analysis across five consecutive vintages to determine their typicity and quality. Free and glycosidically-bound aroma compounds were isolated by solid phase extraction (SPE) to later be analysed using gas chromatography-mass spectrometry (GC/MS). Seventy-four (74) free aroma compounds and thirty-six (36) bound aroma compounds were identified and quantified in La Mancha Verdejo wines oven this five year period. Based on the result, Verdejo white wines presents a complex chemical profile with a wealth of aromas in its aromatic composition. The sensory profile of Verdejo wines was evaluated by experienced wine-tasters and was characterised by fresh, citric, green apple, fruity and tropical fruit aroma descriptors. This study shows the first complete aromatic characterisation of La Mancha Verdejo white wines, also the data suggest that these wines present a great aromatic potential. PMID:25466143

Sánchez-Palomo, E; Alonso-Villegas, R; González Viñas, M A

2015-04-15

470

Reversible Aggregation of Albumin  

NASA Astrophysics Data System (ADS)

We explore the interactions in synovial fluid involving the polyelectrolyte sodium hyaluronate (NaHA) and plasma proteins in their native state (albumin and globulins). Rheological measurements on synovial fluid show it to be highly viscoelastic and also rheopectic (stress increases with time in steady shear). Equilibrium dialysis confirms the findings of Ogston and Dubin that there is no association between NaHA and albumin at physiological pH and salt. What we find instead is a reversible aggregation of albumin, with an association energy of order 3kT and commensurate association lifetime of order microseconds. Certain anti-inflammatory drugs are shown to prevent this reversible aggregation. The implications of these findings for synovial fluid and blood rheology are discussed.

Colby, Ralph H.; Oates, Katherine M. N.; Krause, Wendy E.; Jones, Ronald L.

2004-03-01

471

Reversed field pinch diagnostics  

SciTech Connect

The Reversed Field Pinch (RFP) is a toroidal, axisymmetric magnetic confinement configuration characterized by a magnetic field configuration in which the toroidal magnetic field is of similar strength to the poloidal field, and is reversed at the edge compared to the center. The RFP routinely operates at high beta, and is a strong candidate for a compact fusion device. Relevant attributes of the configuration will be presented, together with an overview of present and planned experiments and their diagnostics. RFP diagnostics are in many ways similar to those of other magnetic confinement devices (such as tokamaks); these lectures will point out pertinent differences, and will present some diagnostics which provide special insights into unique attributes of the RFP.

Weber, P.G.

1986-01-01

472

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

473

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

474

Inhibition of epidermal growth factor signaling by the cardiac glycoside ouabain in medulloblastoma  

PubMed Central

Epidermal growth factor (EGF) signaling regulates cell growth, proliferation, and differentiation. Upon receptor binding, EGF triggers cascades of downstream signaling, including the MAPK and phosphoinositide-3-kinase (PI3K)/Akt signaling pathways. Aberrant expression/activation of EGFR is found in multip