Sample records for plant glycosides chemistry
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Nectar chemistry mediates the behavior of parasitized bees: consequences for plant fitness.
Richardson, Leif L; Bowers, M Deane; Irwin, Rebecca E
2016-02-01
Plants produce an array of secondary metabolites that play important ecological roles as anti-herbivore and anti-pathogen defenses. Many herbivores experience physiological costs when they consume secondary metabolites, yet some also benefit, for example when these chemicals confer resistance to parasites and predators. Secondary metabolites are often present in nectar and pollen, which is paradoxical given that floral rewards are important in the attraction of mutualists rather than deterrence of antagonists. Motivated by studies of interactions among plants, herbivores, and parasites, as well as research showing that secondary metabolites can reduce bee disease, we characterized the occurrence of two iridoid glycosides, aucubin and catalpol, in floral rewards and other tissues of the bee pollinated plant, Chelone glabra. We then experimentally investigated effects of nectar iridoid glycoside concentrations on the foraging behavior of bumble bee pollinators naturally afflicted by a parasitoid fly and a protozoan intestinal parasite, and subsequent effects on an estimate of plant reproduction. We found that floral nectar had lower iridoid glycoside concentrations than leaves, pollen, and corollas, and that, compared to those plant parts, the relative ratio of the two primary iridoid glycosides, aucubin and catalpol, was reversed in nectar. Whether bees carried parasitoid fly larvae did not affect their response to nectar chemistry; however, there was a significant interaction between protozoan parasite infection and nectar treatment, with infected bees foraging longer at flowers with high compared to low nectar iridoid glycoside concentrations. Parasitized bees were also more likely to return to inflorescences with high iridoid glycoside nectar. Consequently, flowers in the high iridoid glycoside nectar treatment donated significantly more pollen to conspecific stigmas than did flowers in the low iridoid glycoside treatment, suggesting an increase in male plant fitness. Taken together, these results demonstrate that nectar secondary metabolites can mediate the behavior of pollinators with subsequent benefits for estimates of plant reproduction.
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Xue, Zhenzhen; Yang, Bin
2016-07-29
Phenylethanoid glycosides (PhGs) are widely distributed in traditional Chinese medicines as well as in other medicinal plants, and they were characterized by a phenethyl alcohol (C₆-C₂) moiety attached to a β-glucopyranose/β-allopyranose via a glycosidic bond. The outstanding activity of PhGs in diverse diseases proves their importance in medicinal chemistry research. This review summarizes new findings on PhGs over the past 10 years, concerning the new structures, their bioactivities, including neuroprotective, anti-inflammatory, antioxidant, antibacterial and antivirus, cytotoxic, immunomodulatory, and enzyme inhibitory effects, and pharmacokinetic properties.
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Miehe-Steier, Annegret; Roscher, Christiane; Reichelt, Michael; Gershenzon, Jonathan; Unsicker, Sybille B.
2015-01-01
A few studies in the past have shown that plant diversity in terms of species richness and functional composition can modify plant defense chemistry. However, it is not yet clear to what extent genetic differentiation of plant chemotypes or phenotypic plasticity in response to diversity-induced variation in growth conditions or a combination of both is responsible for this pattern. We collected seed families of ribwort plantain (Plantago lanceolata) from six-year old experimental grasslands of varying plant diversity (Jena Experiment). The offspring of these seed families was grown under standardized conditions with two levels of light and nutrients. The iridoid glycosides, catalpol and aucubin, and verbascoside, a caffeoyl phenylethanoid glycoside, were measured in roots and shoots. Although offspring of different seed families differed in the tissue concentrations of defensive metabolites, plant diversity in the mothers' environment did not explain the variation in the measured defensive metabolites of P. lanceolata offspring. However secondary metabolite levels in roots and shoots were strongly affected by light and nutrient availability. Highest concentrations of iridoid glycosides and verbascoside were found under high light conditions, and nutrient availability had positive effects on iridoid glycoside concentrations in plants grown under high light conditions. However, verbascoside concentrations decreased under high levels of nutrients irrespective of light. The data from our greenhouse study show that phenotypic plasticity in response to environmental variation rather than genetic differentiation in response to plant community diversity is responsible for variation in secondary metabolite concentrations of P. lanceolata in the six-year old communities of the grassland biodiversity experiment. Due to its large phenotypic plasticity P. lanceolata has the potential for a fast and efficient adjustment to varying environmental conditions in plant communities of different species richness and functional composition. PMID:26336100
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Calder, W John; Horn, Kevin J; St Clair, Samuel B
2011-06-01
Disturbance patterns strongly influence plant community structure. What remains less clear, particularly at a mechanistic level, is how changes in disturbance cycles alter successional outcomes in plant communities. There is evidence that fire suppression is resulting in longer fire return intervals in subalpine forests and that these lengthened intervals increase competitive interactions between aspen and conifer species. We conducted a field and greenhouse study to compare photosynthesis, growth and defense responses of quaking aspen and subalpine fir regeneration under light reductions and shifts in soil chemistry that occur as conifers increase in dominance. The studies demonstrated that aspen regeneration was substantially more sensitive to light and soil resource limitations than that of subalpine fir. For aspen, light reductions and/or shifts in soil chemistry limited height growth, biomass gain, photosynthesis and the production of defense compounds (phenolic glycosides and condensed tannins). Biomass gain and phenolic glycoside concentrations were co-limited by light reduction and changes in soil chemistry. In contrast, subalpine fir seedlings tended to be more tolerant of low light conditions and showed no sensitivity to changes in soil chemistry. Unlike aspen, subalpine fir increased its root to shoot ratio on conifer soils, which may partially explain its maintenance of growth and defense. The results suggest that increasing dominance of conifers in subalpine forests alters light conditions and soil chemistry in a way that places greater physiological and growth constraints on aspen than subalpine fir, with a likely outcome being more successful recruitment of conifers and losses in aspen cover.
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Novel application of 2-[(18)F]fluoro-2-deoxy-D-glucose to study plant defenses.
Ferrieri, Abigail P; Appel, Heidi; Ferrieri, Richard A; Schultz, Jack C
2012-11-01
Since its first use in humans in 1976, 2-[¹⁸F]fluoro-2-deoxy-d-glucose (¹⁸FDG) continues to serve as a tracer to measure tissue glucose metabolism in medical imaging. Here we demonstrate a novel use for this tracer to study glycoside biosynthesis in plants as a measure of plant response to defense induction. Coupling autoradiography with radio high-performance liquid chromatography analysis of tissue extracts, we examined the combined effects of leaf wounding and treatment using the potent plant defense hormone, methyl jasmonate (MeJA), to measure tracer distribution and tracer use in secondary defense chemistry in Arabidopsis thaliana. We hypothesized that competing sinks like roots and reproductive tissues, as well as vascular architecture, would impact the induction of phenolic defenses of the plant that make use of glucose in glycoside formation by altering distribution and metabolic utilization of ¹⁸FDG. Our studies showed that leaf orthostichy defined the major route of ¹⁸FDG transport in both vegetative and reproductive plants when a single petiole was cut as the entry point for tracer introduction. However, when nonorthostichous leaves were damaged and treated with MeJA, ¹⁸FDG was transported in its intact form to these leaves 3 h later, where it was incorporated into phenolic glycosides. Our work demonstrates a new use for ¹⁸FDG in plant science with insights into carbohydrate allocation that contradict conclusions of previous studies showing transport of resources away from damaged sites. Copyright © 2012 Elsevier Inc. All rights reserved.
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NASA Astrophysics Data System (ADS)
Augustin, Line A.
This thesis is the account of two research works. The first part reports the synthesis of O- and C- and aza-C-glycosides of beta-Galactosylceramide (GalCer) that contain simple ceramide substitutes, and the initial results of their binding with gp120 of HIV-1. The O-glycosides were prepared via an established procedure. The C- and aza-C-glycosides originated from a central C1-substituted galactal precursor, and their synthesis is illustrative of a potentially general method for pairs of C- and aza-C-beta-galactosides. They aza-C-glycoside with a simple C-17 hydrocarbon chain exhibited significant higher affinity than GalCer, whereas the corresponding C-glycoside was as active as GalCer. The second part describes the ethnographic study of the enactment of the chemistry knowledge of a high school student at a summer program and the influence of a cultural practice, othermothering, on her ability to perform well on her chemistry Regents Exams. Kelly, an 11th grade student exhibited very good understanding of the chemistry curriculum in the classroom, the laboratory period and the tutoring sessions where she plays a caring role for her peers. The same level of understanding was not reflected on the paper pencil exams taken during the summer program.
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Annotation and comparative analysis of the glycoside hydrolase genes in Brachypodium distachyon
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyler, Ludmila; Bragg, Jennifer; Wu, Jiajie
2010-01-01
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 hydrolasemore » 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.« less
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Pregnane glycosides from Sansevieria trifasciata.
Mimaki, Y; Inoue, T; Kuroda, M; Sashida, Y
1997-01-01
Phytochemical analysis of the whole plant of Sansevieria trifasciata, one of the most common Agavaceae plants, has resulted in the isolation of four new pregnane glycosides. Their structures have been determined by spectroscopic analysis and acid- and alkaline-catalysed hydrolysis to be 1 beta,3 beta-dihydroxypregna-5,16-dien-20-one glycosides. This is believed to be the first report of the isolation of the pregnane glycosides from a plant of the family Agavaceae.
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Lankin, David C.; Cisowska, Tamara; Chen, Shao-Nong; Pauli, Guido F.; van Breemen, Richard B.
2016-01-01
The roots/rhizomes of black cohosh (Actaea racemosa L. syn. Cimicifuga racemosa [L]. Nutt., Ranunculaceae) have been used traditionally by Native Americans to treat colds, rheumatism, and a variety of conditions related to women’s health. In recent years black cohosh preparations have become popular dietary supplements among women seeking alternative treatments for menopausal complaints. The popularity of the plant has led to extensive phytochemical and biological investigations, including several clinical trials. Most of the phytochemical and biological research has focused on two abundant classes of compounds: the triterpene glycosides and phenolic acids. A third group of phytoconstituents that has received far less attention consists of the alkaloids and related compounds that contain nitrogen. This chapter summarizes the current state of knowledge of the chemistry and biological activities associated with this group of constituents and provides some perspective on their significance for future research on this interesting plant. PMID:27795590
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Seki, Hikaru; Tamura, Keita; Muranaka, Toshiya
2018-06-01
Increased public awareness of negative health effects associated with excess sugar consumption has triggered increasing interest in plant-derived natural sweeteners. Steviol glycosides are a group of highly sweet diterpene glycosides contained in the leaves of stevia (Stevia rebaudiana). Mogrosides, extracted from monk fruit (Siraitia grosvenorii), are a group of cucurbitane-type triterpenoid glycosides. Glycyrrhizin is an oleanane-type triterpenoid glycoside derived from the underground parts of Glycyrrhiza plants (licorice). This review focuses on the natural isoprenoid sweetening agents steviol glycosides, mogrosides, and glycyrrhizin, and describes recent progress in gene discovery and elucidation of the catalytic functions of their biosynthetic enzymes. Recently, remarkable progress has been made in engineering the production of various plant-specialized metabolites in microbial hosts such as Saccharomyces cerevisiae via the introduction of biosynthetic enzyme genes. Perspectives on the microbial production of plant-derived natural sweeteners are also discussed.
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Okoye, Festus B C; Sawadogo, Wamtinga Richard; Sendker, Jandirk; Aly, Amal H; Quandt, Bettina; Wray, Victor; Hensel, Andreas; Esimone, Charles O; Debbab, Abdessamad; Diederich, Marc; Proksch, Peter
2015-12-24
Olax mannii Oliv. (Olacaceae) is among the many medicinal plants used in Nigeria for the ethnomedicinal management of both cancer and inflammation. Such plants represent potential sources of innovative therapeutic agents for the treatment of cancer and other malignant disorders. While the majority of medicinal plants exert their anticancer effects by direct cytotoxicity on tumor cells, it is important that other mechanisms through which these plants can exhibit anticancer effects are investigated. Preliminary studies indicated that Olax mannii leaves are rich sources of novel flavonoid glycosides. The detailed chemistry as well the mechanisms through which these flavonoid constituents may exert their cancer chemo-preventive and therapeutic effects are, however, not yet investigated. The aim of this study is to carry out a detailed chemical investigation of Olax mannii leaves and the effects of the isolated constituents on the nuclear factor kappa B (NF-κB) pathway. A methanol leaf extract was subjected to various chromatographic separations to achieve isolation of flavonoid glycosides and the structures of the isolated compounds were elucidated by a combination of 1D and 2D NMR and high resolution mass spectrometry. Biological activities were assessed by measurement of cellular viability and proliferation using quantitative IncuCyte videomicroscopy, trypan blue staining and by quantification of the number of metabolically active K562 cells based on quantitation of ATP. The effect of the compounds on the inhibition of the NF-κB pathway as well as toxicity towards peripheral blood mononuclear cells to evaluate differential toxicity was also assayed. Chemical investigation of the methanol leaf extract of the plant material led to the isolation of three new flavonoid triglycosides, kaempferol 3-O-[α-D-apiofuranosyl-(1 → 2)-α-L-arabinofuranoside]-7-O-α-L-rhamnopyranoside (1), kaempferol 3-O-[β-D-glucopyranosyl-(1 → 2)-α-L-arabinofuranoside]-7-O-α-L-rhamnopyranoside (2), kaempferol 3-O-[β-D-arabinopyranosyl-(1→4)-α-L-rhamnopyranoside]-7-O-α-L-rhamnopyranoside (3), in addition to fourteen known flavonoid glycosides (4-17). Of all the tested compounds, only compound 9 (kaempferol 3-O-α-L-rhamnopyranoside) exhibited promising and specific antiproliferative activity on human K562 chronic myelogenous leukemia cells and dose-dependently inhibited NF-κB transactivation. The presence of this flavonoid glycoside and derivatives may account for the reported efficacy of Olax mannii leaf extract in the ethnomedicinal management of cancer and inflammation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
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Pankoke, Helga; Buschmann, Torsten; Müller, Caroline
2013-10-01
The typical defense compounds of Plantaginaceae are the iridoid glycosides, which retard growth and/or enhance mortality of non-adapted herbivores. In plants, glycosidic defense compounds and hydrolytic enzymes often form a dual defense system, in which the glycosides are activated by the enzymes to exert biological effects. Yet, little is known about the activating enzymes in iridoid glycoside-containing plants. To examine the role of plant-derived β-glucosidases in the dual defense system of two common plantain species, Plantago lanceolata and Plantago major, we determined the concentration of iridoid glycosides as well as the β-glucosidase activity in leaves of different age. To investigate the presence of other leaf metabolites potentially involved in plant defense, we used a metabolic fingerprinting approach with ultra-high performance liquid chromatography coupled with time-of-flight-mass spectrometry. According to the optimal defense hypothesis, more valuable parts such as young leaves should be better protected than less valuable parts. Therefore, we expected that both, the concentrations of defense compounds as well as the β-glucosidase activity, should be highest in younger leaves and decrease with increasing leaf age. Both species possessed β-glucosidase activity, which hydrolyzed aucubin, one of the two most abundant iridoid glycosides in both plant species, with high activity. In line with the optimal defense hypothesis, the β-glucosidase activity in both Plantago species as well as the concentration of defense-related metabolites such as iridoid glycosides correlated negatively to leaf age. When leaf extracts were incubated with bovine serum albumin and aucubin, SDS-PAGE revealed a protein-denaturing effect of the leaf extracts of both plantain species, suggesting that iridoid glycosides and plant β-glucosidase interact in a dual defense system. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Deng, Kai; Takasuka, Taichi E; Heins, Richard; Cheng, Xiaoliang; Bergeman, Lai F; Shi, Jian; Aschenbrener, Ryan; Deutsch, Sam; Singh, Seema; Sale, Kenneth L; Simmons, Blake A; Adams, Paul D; Singh, Anup K; Fox, Brian G; Northen, Trent R
2014-07-18
Glycoside hydrolases (GHs) are critical to cycling of plant biomass in the environment, digestion of complex polysaccharides by the human gut microbiome, and industrial activities such as deployment of cellulosic biofuels. High-throughput sequencing methods show tremendous sequence diversity among GHs, yet relatively few examples from the over 150,000 unique domain arrangements containing GHs have been functionally characterized. Here, we show how cell-free expression, bioconjugate chemistry, and surface-based mass spectrometry can be used to study glycoside hydrolase reactions with plant biomass. Detection of soluble products is achieved by coupling a unique chemical probe to the reducing end of oligosaccharides in a stable oxime linkage, while the use of (13)C-labeled monosaccharide standards (xylose and glucose) allows quantitation of the derivatized glycans. We apply this oxime-based nanostructure-initiator mass spectrometry (NIMS) method to characterize the functional diversity of GHs secreted by Clostridium thermocellum, a model cellulolytic organism. New reaction specificities are identified, and differences in rates and yields of individual enzymes are demonstrated in reactions with biomass substrates. Numerical analyses of time series data suggests that synergistic combinations of mono- and multifunctional GHs can decrease the complexity of enzymes needed for the hydrolysis of plant biomass during the production of biofuels.
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Chlorophyll Catabolites in Senescent Leaves of the Plum Tree (Prunus domestica).
Erhart, Theresia; Mittelberger, Cecilia; Vergeiner, Clemens; Scherzer, Gerhard; Holzner, Barbara; Robatscher, Peter; Oberhuber, Michael; Kräutler, Bernhard
2016-11-01
In cold extracts of senescent leaves of the plum tree (Prunus domestica ssp. domestica), six colorless non-fluorescent chlorophyll catabolites (NCCs) were characterized, named Pd-NCCs. In addition, several minor NCC fractions were tentatively classified. The structure of the most polar one of the NCCs, named Pd-NCC-32, featured an unprecedented twofold glycosidation pattern. Three of the NCCs are also functionalized at their 3 2 -position by a glucopyranosyl group. In addition, two of these glycosidated NCCs carry a dihydroxyethyl group at their 18-position. In the polar Pd-NCC-32, the latter group is further glycosidated at the terminal 18 2 -position. Four other major Pd-NCCs and one minor Pd-NCC were identified with five NCCs from higher plants known to belong to the 'epi'-series. In addition, tentative structures were derived for two minor fractions, classified as yellow chlorophyll catabolites, which represented (formal) oxidation products of two of the observed Pd-NCCs. The chlorophyll catabolites in leaves of plum feature the same basic structural pattern as those found in leaves of apple and pear trees. © 2016 The Authors. Chemistry & Biodiversity Published by Wiley-VHCA AG, Zurich, Switzerland.
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New lignan glycosides from Justicia procumbens.
Jin, Hong; Yang, Shu; Dong, Jun-Xing
2017-01-01
Four new lignan glycosides (1-4), named procumbenosides I, K, L, and M, together with cleistanthin B (5) reported for the first time in the genus Justicia, and 5 other known arylnaphthalene lignan glycosides (6-10) were isolated from the whole plant of Justicia procumbens. The structures of the new compounds were elucidated by extensive one-dimensional (1D) and two-dimensional (2D) NMR experiments and mass spectrometry. Procumbenoside M (4) was a rare sesquilignan glycoside never previously reported in the species of Justicia. The paper also provided insight into the conformational equilibria existing in the lignan glycosides of the plant.
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The pharmacological activity of medical herbs after microbiological decontamination by irradiation
NASA Astrophysics Data System (ADS)
Owczarczyk, H. B.; Migdał, W.; K ȩdzia, B.
2000-03-01
In the Institute of Nuclear Chemistry and Technology research on microbiological decontamination of medicinal herbs by irradiation has been carried out since 1996. It was shown that using ionizing radiation (a dose of 10 kGy) can obtain satisfactory results of microbiological decontamination of these products. The content of essential biologically active substances such as essential oils, flavonoids, glycosides, anthocyans, antra-compounds, poliphenoloacids, triterpene saponins, oleanosides and plants mucus did not change significantly after irradiation. Pharmacological activity of medicinal herbs has been found satisfactory after microbiological decontamination by irradiation.
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Janssen, Hans-Gerd; Swindells, Chris; Gunning, Philip; Wang, Weijun; Grün, Christian; Mahabir, Krishna; Maharaj, Vinesh J; Apps, Peter J
2008-06-09
High-performance liquid chromatography (HPLC)-UV and HPLC-Mass Spectrometry (MS) methods were developed for the quantitative analysis of the family of Hoodia gordonii steroid glycosides with appetite suppressing properties in dried plant material, in purified and enriched extracts and in various prototype food-products fortified with H. gordonii extracts. For solid materials, e.g. dried plants or for non-fatty foods, extraction of the steroid glycosides is performed using methanol. For products where the steroid glycosides are present in an oil matrix, direct injection of the oil after dilution in tetrahydrofuran is applied. The HPLC separation is performed on an octyl-modified reversed-phase column in the gradient mode with UV detection at lambda = 220 nm. Quantification is performed against an external calibration line prepared using either one of the pure steroid glycosides or geranyl-tiglate. Short- and long-term repeatabilities of the methods are better than 3 and 6%, respectively. Recoveries are better than 85%, even in the analysis of the least abundant steroid glycosides in a complex yoghurt drink. Linearity is better than 3-4 orders of magnitude and the detection limits are below approximately 2 microg g(-1) for the individual steroid glycosides in dried plant material and food products. HPLC-MS is used to confirm that the steroid glycosides contain the characteristic steroid core, the carbohydrate chain and the tigloyl group.
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Hostplant suitability and defensive chemistry of the Catalpa sphinx, Ceratomia catalpae.
Bowers, M Deane
2003-10-01
The growth and survival of the Catalpa sphinx, Ceratomia catalpae (Sphingidae), were measured on five different species of Catalpa: C. bignonioides, C. bungeii, C. fargeseii, C. ovata, and C. speciosa. Larval growth varied significantly among these host plant species; however, survival did not differ. Quantification of the iridoid glycoside content of larvae, pupae, adults, larval frass, and leaves of the larval host plant, C. bignonioides, by gas chromatography showed that leaves contained both catalpol and catalposide; larvae, pupae, and frass contained only catalpol; and the adults contained no detectable iridoid glycosides. Amounts were highest in the larvae and declined in the pupal stage. Very small amounts of catalpol were detected in adults of the parasitoid, Cotesia congregata, and in the silken cocoons. The hemolymph in which the parasitoid larvae grew contained over 50% dry weight catalpol. Larvae of C. catalpae often regurgitate when disturbed. This may serve as a defense against predators. A comparison of the growth of larvae pinched with forceps to induce regurgitation with those that were not so treated showed that larvae that were pinched, and usually regurgitated, grew significantly more slowly than those that were not.
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Cistanches Herba: An overview of its chemistry, pharmacology, and pharmacokinetics property.
Fu, Zhifei; Fan, Xiang; Wang, Xiaoying; Gao, Xiumei
2018-06-12
Cistanches Herba is an Orobanchaceae parasitic plant. As a commonly used Traditional Chinese Medicine (TCM), its traditional functions include treating kidney deficiency, impotence, female infertility and senile constipation. Chemical analysis of Cistanches Herba revealed that phenylethanoid glycosides, iridoids, lignans, oligosaccharides, and polysaccharides were the main constituents. Pharmacological studies demonstrated that Cistanches Herba exhibited neuroprotective, immunomodulatory, hormonal balancing, anti-fatigue, anti-inflammatory, hepatoprotection, anti-oxidative, anti-bacterial, anti-viral, and anti-tumor effects, etc. The aim of this review is to provide updated, comprehensive and categorized information on the phytochemistry, pharmacological research and pharmacokinetics studies of the major constituents of Cistanches Herba. The literature search was conducted by systematic searching multiple electronic databases including SciFinder, ISI Web of Science, PubMed, Google Scholar and CNKI. Information was also collected from journals, local magazines, books, monographs. To date, more than 100 compounds have been isolated from this genus, include phenylethanoid glycosides, carbohydrates, lignans, iridoids, etc. The crude extracts and isolated compounds have exhibited a wide range of in vitro and in vivo pharmacologic effects, such as neuroprotective, immunomodulatory, anti-inflammatory, hepatoprotection, anti-oxidative, anti-bacterial, and anti-tumor effects. The phenylethanoid glycosides, echinacoside and acteoside have attracted the most attention for their significantly neuropharmacology effects. Pharmacokinetic studies of echinacoside and acteoside also have also been summarized. Phenylethanoid glycosides have demonstrated wide pharmacological actions and have great clinical value if challenges such as poor bioavailability, fast and extensive metabolism are addressed. Apart from phenylethanoid glycosides, other constituents of Cistanches Herba, their pharmacological activities and underlying mechanisms are also need to be studied further. Copyright © 2017. Published by Elsevier B.V.
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A review of chemistry and biological activities of the genus Aerva--a desert plant.
Chawla, Payal; Chawla, Amit; Vasudeva, Neeru; Sharma, Surendra Kumar
2012-01-01
There are approximately 28 species of Aerva genus, but only a few species are medicinal of which A. persica, A. lanata and A. javanica are of great value. A number of flavonol glycosides (e.g., aervanone, kaempferol-3-galactoside, isorhamnetin-3-O-β-D-glucoside) have been reported from Aerva persica as major phytoconstituents and the minor constituents are β-cyanins (glycine betaine and trigonelline), sterols and carbohydrates. This plant is used as medicinal herb in several traditional systems of medicine all over the world, like diuretic, demulcent, purgative, emetic and tinder. Aerva plants are used to cure ulcer, lithiasis, dropsical affections, eye affection, toothache, headache, in disorders of abdomen and inflammation of internal organs. Roots and flowers are reported to possess hypoglycemic, antioxidant, anthelmintic, analgesic, antimalarial, antivenin activities and medicinal properties against rheumatism and kidney troubles.
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Prudic, Kathleen L; Khera, Smriti; Sólyom, Anikó; Timmermann, Barbara N
2007-06-01
The viceroy-monarch and viceroy-queen butterfly associations are classic examples of mimicry. These relationships were originally classified as Batesian, or parasitic, but were later reclassified as Müllerian, or mutalistic, based on predator bioassays. The Müllerian reclassification implies that viceroy is unpalatable because it too is chemically defended like the queen and the monarch. However, unlike the queen and the monarch, the viceroy defensive chemistry has remained uncharacterized. We demonstrate that the viceroy butterfly (Limenitis archippus, Nymphalidae) not only sequesters nonvolatile defensive compounds from its larval host-plant, the Carolina willow (Salix caroliniana, Salicaceae), but also secretes volatile defensive compounds when disturbed. We developed liquid chromatography-mass spectrometry-mass spectrometry methods to identify a set of phenolic glycosides shared between the adult viceroy butterfly and the Carolina willow, and solid phase microextraction and gas chromatography-mass spectrometry methods to identify volatile phenolic compounds released from stressed viceroy butterflies. In both approaches, all structures were characterized based on their mass spectral fragmentation patterns and confirmed with authentic standards. The phenolics we found are known to deter predator attack in other prey systems, including other willow-feeding insect species. Because these compounds have a generalized defensive function at the concentrations we described, our results are consistent with the Müllerian reclassification put forth by other researchers based on bioassay results. It seems that the viceroy butterfly possesses chemical defenses different from its monarch and queen butterfly counterparts (phenolic glycosides vs. cardiac glycosides, respectively), an unusual phenomenon in mimicry warranting future study.
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Jaworska, Karolina; Krynitsky, Alexander J; Rader, Jeanne I
2012-01-01
Simultaneous separation of steviol and steviol glycosides is challenging because of differences in their polarity and chemical structure. In this study, simultaneous analysis of steviol and steviol glycosides was achieved by LC with UV detection using a mixed-mode RP weak anion exchange chromatography column. Steviol and seven steviol glycosides were analyzed on an Acclaim Mixed-Mode Wax-1 (Dionex) column with a linear gradient of deionized water adjusted to pH 3.00 with phosphoric acid and acetonitrile. The extraction was performed by sonicating dry plant material at 40 degreesC in acetonitrile-water (30 + 70, v/v). LOQ values (mg/g dry weight of plant material) were rebaudioside B, 0.50; steviol, 0.70, dulcoside A, 1.0; steviolbioside, 1.2; stevioside and rebaudioside C, 2.0; rebaudioside D, 3.3; and rebaudioside A, 5.0. The method demonstrated suitable performance for all analytes tested with respect to accuracy (mean recoveries 95-99%), intraday and interday precision for retention times (0.070-0.28% and 0.33-1.0% RSD, respectively), and linearity. The method was used to authenticate steviol glycosides in several samples of Stevia plant material as well as to quantitate steviol glycosides in dietary supplements containing Stevia.
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Warashina, Tsutomu; Miyase, Toshio
2018-01-01
Previously, phytochemical investigation of the roots of Asclepias tuberosa (Asclepiadaceae) led to the isolation of some 8,12;8,20-diepoxy-8,14-secopregnane tri-, tetra-, and penta-glycosides. An additional eight new minor 8,12;8,20-diepoxy-8,14-secopregnane glycosides were afforded in the recent investigation of this plant. These glycosides consisted of six or seven 2,6-dideoxy-hexopyranoses together with the aglycone, tuberogenin. The structures of each of these compounds were established using NMR, mass spectroscopic analysis and chemical evidence. As 8,12;8,20-diepoxy-8,14-secopregnane-type glycosides were observed only in A. tuberosa, these compounds were considered to be characteristic phytochemicals of this plant.
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ERIC Educational Resources Information Center
Sall, Eri; And Others
1978-01-01
Describes an undergraduate biological chemistry laboratory experiment which provides students with an example of pseudo-first-order kinetics with the cardiac glycoside inhibition of mammalism sodium and potassium transport. (SL)
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Kohl, Kevin D; Samuni-Blank, Michal; Lymberakis, Petros; Kurnath, Patrice; Izhaki, Ido; Arad, Zeev; Karasov, William H; Dearing, M Denise
2016-01-01
Plant secondary compounds (PSCs) have profound influence on the ecological interaction between plants and their consumers. Glycosides, a class of PSC, are inert in their intact form and become toxic on activation by either plant β-glucosidase enzymes or endogenous β-glucosidases produced by the intestine of the plant-predator or its microbiota. Many insect herbivores decrease activities of endogenous β-glucosidases to limit toxin exposure. However, such an adaptation has never been investigated in nonmodel mammals. We studied three species of spiny mice (Acomys spp.) that vary in their feeding behavior of the glycoside-rich fruit of Ochradenus baccatus. Two species, the common (Acomys cahirinus) and Crete (Acomys minous) spiny mice, behaviorally avoid activating glycosides, while the golden spiny mouse (Acomys russatus) regularly consumes activated glycosides. We fed each species a nontoxic diet of inert glycosides or a toxic diet of activated fruit toxins and investigated the responses of intestinal and microbial β-glucosidase activities. We found that individuals feeding on activated toxins had lower intestinal β-glucosidase activity and that the species that behaviorally avoid activating glycosides also had lower intestinal β-glucosidase activity regardless of treatment. The microbiota represented a larger source of toxin liberation, and the toxin-adapted species (golden spiny mouse) exhibited almost a fivefold increase in microbial β-glucosidase when fed activated toxins, while other species showed slight decreases. These results are contrary to those in insects, where glycoside-adapted species have lower β-glucosidase activity. The glycoside-adapted golden spiny mouse may have evolved tolerance mechanisms such as enhanced detoxification rather than avoidance mechanisms.
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Khan, Haroon; Saeedi, Mina; Nabavi, Seyed Mohammad; Mubarak, Mohammad S; Bishayee, Anupam
2018-04-03
Cancer continues to be a global burden, despite the advancement of various technological and pharmaceutical improvements over the past two decades. Methods for treating cancer include surgery, radiotherapy and chemotherapy in addition to other specialized techniques. On the other hand, medicinal plants have been traditionally employed either as the complementary medicine or dietary agents in the treatment and management of cancer. Medicinal plants are a rich source of secondary metabolites with interesting biological and pharmacological activities. Among these metabolites, glycosides are naturally occurring substances and have outstanding therapeutic potential and clinical utility. Different medical research engines such GoogleScholar, PubMed, SpringerLink, ScienceDirect were used to collect related literature on the subject matter. In this regard, only peer reviewed journals were considered. Emerging results showed that numerous glycosides isolated from various plants possessed marked anticancer activity against a variety of cancer cell lines. Accordingly, the aim of the present review is to shed light on the anticancer effects of glycosides, analyze possible mechanisms of action, and highlight the role of these natural agents as complementary and alternative medicine in combating and managing cancer. The glycosides isolated from different plants demonstrated potent cytotoxic effects against various cancer cell lines in initial preclinical studies. The anticancer effect was mediated through multiple mechanisms; however further detail studies are needed to understand the full potential of glycosides for clinical utility. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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Wu, Lun; Chen, Zhi-Li; Su, Yang; Wang, Qiu-Hong; Kuang, Hai-Xue
2015-02-01
The constituents of Cimicifuga plants have been extensively investigated, and the principal metabolites are 9,19-cyclolanostane triterpenoid glycosides, which are distributed widely in Cimicifuga plants, but not in other members of the Ranunculaceae family, and are considered to be characteristics of the Cimicifuga genus. This type of triterpenoid glycoside possesses several important biological activities. More than 120 cycloartane triterpene glycosides have been isolated from Cimicifuga simplex Wormsk. The aim of this review article is to summarize all the major findings based on the available scientific literatures on C. simplex, with a focus on the identified 9,19-cyclolanostane triterpenoid glycosides. Biological studies of cycloartane triterpene glycosides from Cimicifuga spp. are also discussed. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.
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Barnes, Curtis C; Smalley, Mary K; Manfredi, Kirk P; Kindscher, Kelly; Loring, Hillary; Sheeley, Douglas M
2003-11-01
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.
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Lampert, Evan C; Dyer, Lee A; Bowers, M Deane
2010-09-01
Sequestration of plant compounds by herbivorous insects as a defense against predators is well documented; however, few studies have examined the effectiveness of sequestration as a defense against parasitoids. One assumption of the "nasty host" hypothesis is that sequestration of plant defense compounds is deleterious to parasitoid development. We tested this hypothesis with larvae of the sequestering sphingid Ceratomia catalpae, which is heavily parasitized by the endoparasitoid Cotesia congregata, despite sequestering high concentrations of the iridoid glycoside catalpol from their catalpa host plants. We collected C. catalpae and catalpa leaves from six populations in the Eastern US, and allowed any C. congregata to emerge in the lab. Leaf iridoid glycosides and caterpillar iridoid glycosides were quantified, and we examined associations between sequestered caterpillar iridoid glycosides and C. congregata performance. Caterpillar iridoid glycosides were not associated with C. congregata field parasitism or number of offspring produced. Although wasp survival was over 90% in all populations, there was a slight negative relationship between caterpillar iridoid glycosides and wasp survival. Iridoid glycosides were present in caterpillars at levels that are deterrent to a variety of vertebrate and invertebrate predators. Thus, our results support the alternative hypothesis that unpalatable, chemically defended hosts are "safe havens" for endoparasitoids. Future trials examining the importance of catalpol sequestration to potential natural enemies of C. congregata and C. catalpae are necessary to strengthen this conclusion.
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Carbohydrate Green Chemistry: C-Glycoside Ketones as Potential Chiral Building Blocks
USDA-ARS?s Scientific Manuscript database
"Green chemistry" methods to produce new chemicals from renewable agricultural feedstocks will decrease our dependence on imported petroleum feedstocks and lower the environmental impact of consumer products. Our current research focuses on development of new carbohydrate-based derivatives, "locked...
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Frequency of Cyanogenesis in Tropical Rainforests of Far North Queensland, Australia
MILLER, REBECCA E.; JENSEN, RIGEL; WOODROW, IAN E.
2006-01-01
• Background and Aims Plant cyanogenesis is the release of toxic cyanide from endogenous cyanide-containing compounds, typically cyanogenic glycosides. Despite a large body of phytochemical, taxonomic and ecological work on cyanogenic species, little is known of their frequency in natural plant communities. This study aimed to investigate the frequency of cyanogenesis in Australian tropical rainforests. Secondary aims were to quantify the cyanogenic glycoside content of tissues, to investigate intra-plant and intra-population variation in cyanogenic glycoside concentration and to appraise the potential chemotaxonomic significance of any findings in relation to the distribution of cyanogenesis in related taxa. • Methods All species in six 200 m2 plots at each of five sites across lowland, upland and highland tropical rainforest were screened for cyanogenesis using Feigl–Anger indicator papers. The concentrations of cyanogenic glycosides were accurately determined for all cyanogenic individuals. • Key Results Over 400 species from 87 plant families were screened. Overall, 18 species (4·5 %) were cyanogenic, accounting for 7·3 % of total stem basal area. Cyanogenesis has not previously been reported for 17 of the 18 species, 13 of which are endemic to Australia. Several species belong to plant families or orders in which cyanogenesis has been little reported, if at all (e.g. Elaeocarpaceae, Myrsinaceae, Araliaceae and Lamiaceae). A number of species contained concentrations of cyanogenic glycosides among the highest ever reported for mature leaves—up to 5·2 mg CN g−1 d. wt, for example, in leaves of Elaeocarpus sericopetalus. There was significant variation in cyanogenic glycoside concentration within individuals; young leaves and reproductive tissues typically had higher cyanogen content. In addition, there was substantial variation in cyanogenic glycoside content within populations of single species. • Conclusions This study expands the limited knowledge of the frequency of cyanogenesis in natural plant communities, includes novel reports of cyanogenesis among a range of taxa and characterizes patterns in intra-plant and intra-population variation of cyanogensis. PMID:16520340
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Modi, Arpan; Kumar, Nitish; Narayanan, Subhash
2016-01-01
Stevia (Stevia rebaudiana Bertoni) is a medicinal plant having sweet, diterpenoid glycosides known as steviol glycosides which are 200-300 times sweeter than sucrose (0.4 % solution). They are synthesized mainly in the leaves via plastid localized 2-C-methyl-D-erythrose-4-phosphate pathway (MEP pathway). Fifteen genes are involved in the formation of these glycosides. In the present protocol, a method for the quantification of transcripts of these genes is shown. The work involves RNA extraction and cDNA preparation, and therefore, procedures for the confirmation of DNA-free cDNA preparation have also been illustrated. Moreover, details of plant treatments are not mentioned as this protocol may apply to relative gene expression profile in any medicinal plant with any treatment. The treatments are numbered as T0 (Control), T1, T2, T3, and T4.
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Kahrizi, Danial; Ghaheri, Matin; Yari, Zahra; Yari, Khirollah; Bahraminejad, Sohbat
2018-02-10
Stevia rebaudiana Bertoni is one of two species that contains steviol glycosides. Among steviol glycosides that extracted from leaves, stevioside and rebaudioside A are the two major and the sweetest glycosides that are about 200-300 times sweeter than sucrose with zero calories. The best method for stevia propagation is tissue culture. So, for investigation of nutrients in medium, we studied the effect of different concentrations of MS media (MS, 0.5 MS, 0.25 MS, 0 MS) on morphological traits, UGT74G1 and UGT76G1 genes expression and accumulation of steviol glycosides in stevia leaves. The best growth rate (0.472 mm/d) has occurred in plants grown in MS media. Also, the highest gene expression of UGT74G1 gene (1.000 Total lab unit) was seen under MS treatment. However, the highest expression level of UGT76G1 gene (1.701 Total lab unit) was observed at plants grown in 0 MS. The highest amount of both Stevioside and Rebaudioside A (14.23 and 8.12, respectively) were accumulated in plants under MS treatment. Obviously, dilution of MS media associated with decreasing in both expression of the intended genes and accumulation of steviol glycosides.
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Synthesis and characterization of nanoparticles capped with medicinal plant extracts
NASA Astrophysics Data System (ADS)
Rekulapally, Sujith R.
In this study, synthesis, characterization and biological application of series nanometal (silver, Ag) and nanometal oxide (titania, TiO2) were carried out. These nanomaterials were prepared using wet-chemistry method and then coated using natural plant extract. Three medicinal plants, namely Zingiber officinale (Ginger), Allium sativum (Garlic) and Capsicum annuum (Chili) were chosen as grafting agent to decrease the side-effects and increase the efficiency of NPs towards living organism. Extraction conditions were controlled under 60-100 °C for 8 hrs. Ag and TiO2 NPs were fabricated using colloidal chemistry and variables were controlled at ambient condition. The band gap of TiO2 NPs used as disinfectant was also modified through coating the medicinal plant extracts. The medicinal plant extracts and coated NPs were measured using spectroscopic methods. Ultraviolet-visible spectra indicated the Ag NPs were formed. The peak at 410 nm resulted from the electrons transferred from their ground to the excited state. The broadened full width at half maximum (FWHM) suggested the ultrafine particles were obtained. The lipid soluble compounds, phenols, tri-terpenoids, flavanoids, capsaicinoids, flavonoids, carotenoids, steroids steroidal glycosides, and vitamins were determined from the high performance liquid chromatographical analyses. X-ray powder diffraction indicated that the face-centered cubic Ag (PDF: 00-004-0783, a = 4.0862A, a = 90°) and anatase TiO2 (PDF: 01-08-1285, a = 3.7845, c = 9.5143A, a = 90°) were obtained using colloidal chemistry. Bactericidal activity indicated that these core-shelled TiO 2 were effective (MBC=0.6 ppm, within 30 mins) at inactivating Gram-positive and Gram-negative bacteria. It is proposed that the medicinal extracts enhanced the potency of NPs against bacteria. From our previous study, the Ag NPs were highly effective at inactivating both bacteria.
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Wan, Qun; Parks, Jerry M; Hanson, B Leif; Fisher, Suzanne Zoe; Ostermann, Andreas; Schrader, Tobias E; Graham, David E; Coates, Leighton; Langan, Paul; Kovalevsky, Andrey
2015-10-06
Glycoside hydrolase (GH) enzymes apply acid/base chemistry to catalyze the decomposition of complex carbohydrates. These ubiquitous enzymes accept protons from solvent and donate them to substrates at close to neutral pH by modulating the pKa values of key side chains during catalysis. However, it is not known how the catalytic acid residue acquires a proton and transfers it efficiently to the substrate. To better understand GH chemistry, we used macromolecular neutron crystallography to directly determine protonation and ionization states of the active site residues of a family 11 GH at multiple pD (pD=pH+0.4) values. The general acid glutamate (Glu) cycles between two conformations, upward and downward, but is protonated only in the downward orientation. We performed continuum electrostatics calculations to estimate the pKa values of the catalytic Glu residues in both the apo- and substrate-bound states of the enzyme. The calculated pKa of the Glu increases substantially when the side chain moves down. The energy barrier required to rotate the catalytic Glu residue back to the upward conformation, where it can protonate the glycosidic oxygen of the substrate, is 4.3 kcal/mol according to free energy simulations. These findings shed light on the initial stage of the glycoside hydrolysis reaction in which molecular motion enables the general acid catalyst to obtain a proton from the bulk solvent and deliver it to the glycosidic oxygen.
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Wan, Qun; Parks, Jerry M.; Hanson, B. Leif; Fisher, Suzanne Zoe; Ostermann, Andreas; Schrader, Tobias E.; Graham, David E.; Coates, Leighton; Langan, Paul; Kovalevsky, Andrey
2015-01-01
Glycoside hydrolase (GH) enzymes apply acid/base chemistry to catalyze the decomposition of complex carbohydrates. These ubiquitous enzymes accept protons from solvent and donate them to substrates at close to neutral pH by modulating the pKa values of key side chains during catalysis. However, it is not known how the catalytic acid residue acquires a proton and transfers it efficiently to the substrate. To better understand GH chemistry, we used macromolecular neutron crystallography to directly determine protonation and ionization states of the active site residues of a family 11 GH at multiple pD (pD = pH + 0.4) values. The general acid glutamate (Glu) cycles between two conformations, upward and downward, but is protonated only in the downward orientation. We performed continuum electrostatics calculations to estimate the pKa values of the catalytic Glu residues in both the apo- and substrate-bound states of the enzyme. The calculated pKa of the Glu increases substantially when the side chain moves down. The energy barrier required to rotate the catalytic Glu residue back to the upward conformation, where it can protonate the glycosidic oxygen of the substrate, is 4.3 kcal/mol according to free energy simulations. These findings shed light on the initial stage of the glycoside hydrolysis reaction in which molecular motion enables the general acid catalyst to obtain a proton from the bulk solvent and deliver it to the glycosidic oxygen. PMID:26392527
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Wan, Qun; Parks, Jerry M.; Hanson, B. Leif
Glycoside hydrolase (GH) enzymes apply acid/base chemistry to catalyze the decomposition of complex carbohydrates. These ubiquitous enzymes accept protons from solvent and donate them to substrates at close to neutral pH by modulating the pK a values of key side chains during catalysis. However, it is not known how the catalytic acid residue acquires a proton and transfers it efficiently to the substrate. To better understand GH chemistry, we used macromolecular neutron crystallography to directly determine protonation and ionization states of the active site residues of a family 11 GH at multiple pD (pD = pH + 0.4) values. Themore » general acid glutamate (Glu) cycles between two conformations, upward and downward, but is protonated only in the downward orientation. We performed continuum electrostatics calculations to estimate the pK a values of the catalytic Glu residues in both the apo- and substrate-bound states of the enzyme. The calculated pK a of the Glu increases substantially when the side chain moves down. The energy barrier required to rotate the catalytic Glu residue back to the upward conformation, where it can protonate the glycosidic oxygen of the substrate, is 4.3 kcal/mol according to free energy simulations. Lastly, these findings shed light on the initial stage of the glycoside hydrolysis reaction in which molecular motion enables the general acid catalyst to obtain a proton from the bulk solvent and deliver it to the glycosidic oxygen.« less
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Wan, Qun; Parks, Jerry M.; Hanson, B. Leif; ...
2015-09-21
Glycoside hydrolase (GH) enzymes apply acid/base chemistry to catalyze the decomposition of complex carbohydrates. These ubiquitous enzymes accept protons from solvent and donate them to substrates at close to neutral pH by modulating the pK a values of key side chains during catalysis. However, it is not known how the catalytic acid residue acquires a proton and transfers it efficiently to the substrate. To better understand GH chemistry, we used macromolecular neutron crystallography to directly determine protonation and ionization states of the active site residues of a family 11 GH at multiple pD (pD = pH + 0.4) values. Themore » general acid glutamate (Glu) cycles between two conformations, upward and downward, but is protonated only in the downward orientation. We performed continuum electrostatics calculations to estimate the pK a values of the catalytic Glu residues in both the apo- and substrate-bound states of the enzyme. The calculated pK a of the Glu increases substantially when the side chain moves down. The energy barrier required to rotate the catalytic Glu residue back to the upward conformation, where it can protonate the glycosidic oxygen of the substrate, is 4.3 kcal/mol according to free energy simulations. Lastly, these findings shed light on the initial stage of the glycoside hydrolysis reaction in which molecular motion enables the general acid catalyst to obtain a proton from the bulk solvent and deliver it to the glycosidic oxygen.« less
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NASA Astrophysics Data System (ADS)
Sahu, N. P.; Banerjee, S.; Mondal, N. B.; Mandal, D.
The medicinal activities of plants are generally due to the secondary metabolites (1) which often occur as glycosides of steroids, terpenoids, phenols etc. Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution. The cardiac glycosides also possess this, property but are classified separately because of their specific biological activity. Unlike the cardiac glycosides, saponins generally do not affect the heart. These are classified as steroid or triterpenoid saponins depending on the nature of the aglycone. Steroidal glycosides are naturally occurring sugar conjugates of C27 steroidal compounds. The aglycone of a steroid saponin is usually a spirostanol or a furostanol. The glycone parts of these compounds are mostly oligosaccharides, arranged either in a linear or branched fashion, attached to hydroxyl groups through an acetal linkage (2, 3). Another class of saponins, the basic steroid saponins, contain nitrogen analogues of steroid sapogenins as aglycones.
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Xu, Maojun; Dong, Jufang; Wang, Huizhong; Huang, Luqi
2009-08-01
The antagonistic action between jasmonic acid (JA) and salicylic acid (SA) in plant defence responses has been well documented. However, their relationship in secondary metabolite production is largely unknown. Here, we report that PB90, a protein elicitor from Phytophthora boehmeriae, triggers JA generation, SA accumulation and flavonol glycoside production of Ginkgo biloba cells. JA inhibitors suppress not only PB90-triggered JA generation, but also the elicitor-induced flavonol glycoside production. However, the elicitor can still enhance flavonol glycoside production even though the JA generation is totally inhibited. Over-expression of SA hydrolase gene NahG not only abolishes SA accumulation, but also suppresses the elicitor-induced flavonol glycoside production when JA signalling is inhibited. Interestingly, expression of NahG does not inhibit the elicitor-induced flavonol glycoside accumulation in the absence of JA inhibitors. Moreover, JA levels are significantly enhanced when SA accumulation is impaired in the transgenic cells. Together, the data suggest that both JA and SA are involved in PB90-induced flavonol glycoside production. Furthermore, we demonstrate that JA signalling might be enhanced to substitute for SA to mediate the elicitor-induced flavonol glycoside accumulation when SA signalling is impaired, which reveals an unusual complementary relationship between JA and SA in mediating plant secondary metabolite production.
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Yokosuka, Akihito; Sano, Tomoe; Hashimoto, Ken; Sakagami, Hiroshi; Mimaki, Yoshihiro
2009-12-01
Three new triterpene glycosides (1-3), together with eight known triterpene glycosides (4-11), were isolated from the whole plant of Anemone hupehensis var. japonica (Ranunculaceae). The structures of the new compounds were determined on the basis of spectroscopic analysis and the results of hydrolytic cleavage experiments. The isolated compounds were evaluated for their cytotoxic activities against HL-60 human leukemia cells, HSC-2 human oral squamous carcinoma cells, HSC-4 human oral squamous carcinoma cells, and A549 human lung adenocarcinoma cells.
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NASA Astrophysics Data System (ADS)
Rožman, Marko
2016-01-01
Glycosphingolipid fragmentation behavior was investigated by combining results from analysis of a series of negative ion tandem mass spectra and molecular modeling. Fragmentation patterns extracted from 75 tandem mass spectra of mainly acidic glycosphingolipid species (gangliosides) suggest prominent cleavage of the glycosidic bonds with retention of the glycosidic oxygen atom by the species formed from the reducing end (B and Y ion formation). Dominant product ions arise from dissociation of sialic acids glycosidic bonds whereas product ions resulting from cleavage of other glycosidic bonds are less abundant. Potential energy surfaces and unimolecular reaction rates of several low-energy fragmentation pathways leading to cleavage of glycosidic bonds were estimated in order to explain observed dissociation patterns. Glycosidic bond cleavage in both neutral (unsubstituted glycosyl group) and acidic glycosphingolipids was the outcome of the charge-directed intramolecular nucleophilic substitution (SN2) mechanism. According to the suggested mechanism, the nucleophile in a form of carboxylate or oxyanion attacks the carbon at position one of the sugar ring, simultaneously breaking the glycosidic bond and yielding an epoxide. For gangliosides, unimolecular reaction rates suggest that dominant product ions related to the cleavage of sialic acid glycosidic bonds are formed via direct dissociation channels. On the other hand, low abundant product ions related to the dissociation of other glycosidic bonds are more likely to be the result of sequential dissociation. Although results from this study mainly contribute to the understanding of glycosphingolipid fragmentation chemistry, some mechanistic findings regarding cleavage of the glycosidic bond may be applicable to other glycoconjugates.
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Profiling and Quantification of Phenolics in Stevia rebaudiana Leaves.
Karaköse, Hande; Müller, Anja; Kuhnert, Nikolai
2015-10-21
Stevia rebaudiana (Bertoni) is a plant from the Asteraceae family with significant economic value because of the steviol glycoside sweeteners in its leaves. Chlorogenic acids and flavonoid glycosides of S. rebaudiana from seven different botanical varieties cultivated over two years and harvested three times a year in eight European locations were profiled and quantified in a total of 166 samples. Compounds quantified include chlorogenic acids as well as flavonoid glycosides and aglycons. All phenolic concentration profiles show a perfect Gaussian distribution. Principal component analyses allow distinction between varieties of different geographical origin and distinction between different plant varieties. Although concentrations of all chlorogenic acids showed a positive correlation, no correlation was observed for flavonoid glycosides. Conclusions from these findings with respect to the biosynthesis and functional role of phenolics in S. rebaudiana are discussed.
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Photochemistry and pharmacology of 9, 19-cyclolanostane glycosides isolated from genus Cimicifuga.
Su, Yang; Chi, Wen-Cheng; Wu, Lun; Wang, Qiu-Hong; Kuang, Hai-Xue
2016-10-01
The constituents of Cimicifuga plants have been extensively investigated, and the principal metabolites are 9, 19-cyclolanostane triterpenoid glycosides, which often exhibit extensive pharmacological activities. 9, 19-Cyclolanostane triterpenoid glycosides are distributed widely in genus Cimicifuga rather than in other members of the Ranunculaceae family. So far, more than 140 cycloartane triterpene glycosides have been isolated from Cimicifuga spp.. The aim of this review was to summarize all 9, 19-cyclolanostane triterpenoid glycosides based on the available relevant scientific literatures from 2000 to 2014. Biological studies of cycloartane triterpene glycosides from Cimicifuga spp. are also discussed. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.
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Quantification of sterol lipids in plants by quadrupole time-of-flight mass spectrometry
Wewer, Vera; Dombrink, Isabel; vom Dorp, Katharina; Dörmann, Peter
2011-01-01
Glycerolipids, sphingolipids, and sterol lipids constitute the major lipid classes in plants. Sterol lipids are composed of free and conjugated sterols, i.e., sterol esters, sterol glycosides, and acylated sterol glycosides. Sterol lipids play crucial roles during adaption to abiotic stresses and plant-pathogen interactions. Presently, no comprehensive method for sterol lipid quantification in plants is available. We used nanospray ionization quadrupole-time-of-flight mass spectrometry (Q-TOF MS) to resolve and identify the molecular species of all four sterol lipid classes from Arabidopsis thaliana. Free sterols were derivatized with chlorobetainyl chloride. Sterol esters, sterol glycosides, and acylated sterol glycosides were ionized as ammonium adducts. Quantification of molecular species was achieved in the positive mode after fragmentation in the presence of internal standards. The amounts of sterol lipids quantified by Q-TOF MS/MS were validated by comparison with results obtained with TLC/GC. Quantification of sterol lipids from leaves and roots of phosphate-deprived A. thaliana plants revealed changes in the amounts and molecular species composition. The Q-TOF method is far more sensitive than GC or HPLC. Therefore, Q-TOF MS/MS provides a comprehensive strategy for sterol lipid quantification that can be adapted to other tandem mass spectrometers. PMID:21382968
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Prakash, Indra; Campbell, Mary; Chaturvedula, Venkata Sai Prakash
2012-11-16
Catalytic hydrogenation of rebaudioside B, rebaudioside C, and rebaudioside D; the three ent-kaurane diterpene glycosides isolated from Stevia rebaudiana was carried out using Pd(OH)(2). Reduction of steviol glycosides was performed using straightforward synthetic chemistry with the catalyst Pd(OH)(2) and structures of the corresponding dihydro derivatives were characterized on the basis of 1D and 2D nuclear magnetic resonance (NMR) spectral data indicating that all are novel compounds being reported for the first time. Also, the taste properties of all reduced compounds were evaluated against their corresponding original steviol glycosides and sucrose.
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Synthesis of ent-kaurane diterpene monoglycosides.
Chaturvedula, Venkata Sai Prakash; Klucik, Josef; Upreti, Mani; Prakash, Indra
2011-10-03
Synthesis of two ent-kaurane diterpene glycosides, steviol 19-O-β-D-glucopyranosiduronic acid (steviol glucuronide, 5), and 13-hydroxy ent-kaur-16-en-19-oic acid-β-D-glucopyranosyl ester (7) has been achieved from a common starting material, steviol, using phase transfer catalyst. Also, synthesis of an additional 17-nor-ent-kaurane glycoside, namely 13-methyl-16-oxo-17-nor-ent-kauran-19-oic acid-β-D-glucopyranosyl ester (10) was performed using the starting material isosteviol and similar synthetic methodology. Synthesis of all three steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR as well as mass spectral (MS) data.
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Prakash, Indra; Campbell, Mary; Chaturvedula, Venkata Sai Prakash
2012-01-01
Catalytic hydrogenation of rebaudioside B, rebaudioside C, and rebaudioside D; the three ent-kaurane diterpene glycosides isolated from Stevia rebaudiana was carried out using Pd(OH)2. Reduction of steviol glycosides was performed using straightforward synthetic chemistry with the catalyst Pd(OH)2 and structures of the corresponding dihydro derivatives were characterized on the basis of 1D and 2D nuclear magnetic resonance (NMR) spectral data indicating that all are novel compounds being reported for the first time. Also, the taste properties of all reduced compounds were evaluated against their corresponding original steviol glycosides and sucrose. PMID:23203115
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Triterpenoidal Saponins: Bioactive Secondary Metabolites from Zygophyllum coccineum
2011-01-22
isolation of nine ursane-type triterpene saponins (1?9), including the new one; zygophylloside S (1), together with a known flavonoid glycoside (10) and a...1–9), including the new one; zygophylloside S (1), to- gether with a known flavonoid glycoside (10) and a sterol glyco- side (11).The isolated...Moghazy AM. Zygophyllum coccineum. V. The chemistry of the leaf and stem. J Pharm Sci 1960; 1: 135 4 Eskander EF, Won JH. Hypoglycaemic and
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USDA-ARS?s Scientific Manuscript database
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...
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Molina-Calle, M; Sánchez de Medina, V; Delgado de la Torre, M P; Priego-Capote, F; Luque de Castro, M D
2016-07-01
Stevia is a currently well-known plant thanks to the presence of steviol glycosides, which are considered as sweeteners obtained from a natural source. In this research, a method based on LC-MS/MS by using a triple quadrupole detector was developed for quantitation of 8 steviol glycosides in extracts from Stevia leaves. The ionization and fragmentation parameters for selected reaction monitoring were optimized. Detection and quantitation limits ranging from 0.1 to 0.5ng/mL and from 0.5 to 1ng/mL, respectively, were achieved: the lowest attained so far. The steviol glycosides were quantified in extracts from leaves of seven varieties of Stevia cultivated in laboratory, greenhouse and field. Plants cultivated in field presented higher concentration of steviol glycosides than those cultivated in greenhouse. Thus, the way of cultivation clearly influences the concentration of these compounds. The inclusion of branches together with leaves as raw material was also evaluated, showing that this inclusion modifies, either positively or negatively, the concentration of steviol glycosides. Copyright © 2016 Elsevier B.V. All rights reserved.
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Puttick, G M; Bowers, M D
1988-01-01
The behavioral and physiological effects of plant allelochemicals have been difficult to demonstrate; it is not often clear whether the compounds are deterrent, toxic, or both. In this study, we compared the qualitative and quantitative effects of several iridoid glycosides on a generalist lepidopteran herbivore,Spodoptera eridania (Noctuidae). Larval growth and survivorship and larval preference or avoidance were measured on artificial diets containing different iridoid glycosides at different concentrations. We also tested the toxicity/deterrence of these compounds. We found that iridoid glycosides retarded larval growth significantly at relatively low concentrations and that they were usually avoided in preference tests. The toxicity/ deterrence test did not always reflect the results of these other tests. The merits of using a variety of methods for determining deterrence and/or toxicity of plant allelochemicals are discussed.
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Mass spectrometric imaging of flavonoid glycosides and biflavonoids in Ginkgo biloba L.
Beck, Sebastian; Stengel, Julia
2016-10-01
Ginkgo biloba L. is known to be rich in flavonoids and flavonoid glycosides. However, the distribution within specific plant organs (e.g. within leaves) is not known. By using HPLC-MS and MS/MS we have identified a number of previously known G. biloba flavonoid glycosides and biflavonoids from leaves. Namely, kaempferol, quercetin, isorhamnetin, myricetin, laricitrin/mearnsetin and apigenin glycosides were identified. Furthermore, biflavonoids like ginkgetin/isoginkgetin were also detected. The application of MALDI mass spectrometric imaging, enabled the compilation of concentration profiles of flavonoid glycosides and biflavonoids in G. biloba L. leaves. Both, flavonoid glycosides and biflavonoids show a distinct distribution in leaf thin sections of G. biloba L. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Groenbaek, Marie; Jensen, Sidsel; Neugart, Susanne; Schreiner, Monika; Kidmose, Ulla; Kristensen, Hanne L
2016-04-15
We investigated how concentrations of sensory relevant compounds: glucosinolates (GLSs), flavonoid glycosides, hydroxycinnamic acid derivatives and sugars in kale responded to split dose and reduced nitrogen (N) fertilization, plant age and controlled frost exposure. In addition, frost effects on sensory properties combined with N supply were assessed. Seventeen week old kale plants showed decreased aliphatic GLSs at split dose N fertilization; whereas reduced N increased aliphatic and total GLSs. Ontogenetic effects were demonstrated for all compounds: sugars, aliphatic and total GLSs increased throughout plant development, whereas kaempferol and total flavonoid glycosides showed higher concentrations in 13 week old plants. Controlled frost exposure altered sugar composition slightly, but not GLSs or flavonoid glycosides. Reduced N supply resulted in less bitterness, astringency and pungent aroma, whereas frost exposure mainly influenced aroma and texture. N treatment explained most of the sensory variation. Producers should not rely on frost only to obtain altered sensory properties. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Mishra, Manoj K; Singh, Gaurav; Tiwari, Shalini; Singh, Ruchi; Kumari, Nishi; Misra, Pratibha
2015-01-01
Sterol glycosyltransferases regulate the properties of sterols by catalyzing the transfer of carbohydrate molecules to the sterol moiety for the synthesis of steryl glycosides and acyl steryl glycosides. We have analyzed the functional role of TTG15/UGT80B1 gene of Arabidopsis thaliana in freeze/thaw and heat shock stress using T-DNA insertional sgt knockout mutants. Quantitative study of spatial as well as temporal gene expression showed tissue-specific and dynamic expression patterns throughout the growth stages. Comparative responses of Col-0, TTG15/UGT80B1 knockout mutant and p35S:TTG15/UGT80B1 restored lines were analyzed under heat and freeze stress conditions. Heat tolerance was determined by survival of plants at 42°C for 3 h, MDA analysis and chlorophyll fluorescence image (CFI) analysis. Freezing tolerance was determined by survival of the plants at -1°C temperature in non-acclimatized (NA) and cold acclimatized (CA) conditions and also by CFI analysis, which revealed that, p35S:TTG15/UGT80B1 restored plants were more adapted to freeze stress than TTG15/UGT80B1 knockout mutant under CA condition. HPLC analysis of the plants showed reduced sterol glycoside in mutant seedlings as compared to other genotypes. Following CA condition, both β-sitosterol and sitosterol glycoside quantity was more in Col-0 and p35S:TTG15/UGT80B1 restored lines, whereas it was significantly less in TTG15/UGT80B1 knockout mutants. From these results, it may be concluded that due to low content of free sterols and sterol glycosides, the physiology of mutant plants was more affected during both, the chilling and heat stress. PMID:26382564
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Quantitation of sweet steviol glycosides by means of a HILIC-MS/MS-SIDA approach.
Well, Caroline; Frank, Oliver; Hofmann, Thomas
2013-11-27
Meeting the rising consumer demand for natural food ingredients, steviol glycosides, the sweet principle of Stevia rebaudiana Bertoni (Bertoni), have recently been approved as food additives in the European Union. As regulatory constraints require sensitive methods to analyze the sweet-tasting steviol glycosides in foods and beverages, a HILIC-MS/MS method was developed enabling the accurate and reliable quantitation of the major steviol glycosides stevioside, rebaudiosides A-F, steviolbioside, rubusoside, and dulcoside A by using the corresponding deuterated 16,17-dihydrosteviol glycosides as suitable internal standards. This quantitation not only enables the analysis of the individual steviol glycosides in foods and beverages but also can support the optimization of breeding and postharvest downstream processing of Stevia plants to produce preferentially sweet and least bitter tasting Stevia extracts.
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Advance on the Flavonoid C-glycosides and Health Benefits.
Xiao, Jianbo; Capanoglu, Esra; Jassbi, Amir Reza; Miron, Anca
2016-07-29
The dietary flavonoids, especially their glycosides, are the most vital phytochemicals in diets and are of great general interest due to their diverse bioactivity. Almost all natural flavonoids exist as their O-glycoside or C-glycoside forms in plants. The dietary flavonoid C-glycosides have received less attention than their corresponding O-glycosides. This review summarizes current knowledge regarding flavonoid C-glycosides and their influence on human health. Among the flavonoid C-glycosides, flavone C-glycosides, especially vitexin, isoorientin, orientin, isovitexin and their multiglycosides are more frequently mentioned than others. Flavonoid C-monoglycosides are poorly absorbed in human beings with very few metabolites in urine and blood and are deglycosylated and degraded by human intestinal bacteria in colon. However, flavonoid C-multiglycosides are absorbed unchanged in the intestine and distributed to other tissues. Flavonoid C-glycosides showed significant antioxidant activity, anticancer and antitumor activity, hepatoprotective activity, anti-inflammatory activity, anti-diabetes activity, antiviral activity, antibacterial and antifungal activity, and other biological effects. It looks like that the C-glycosylflavonoids in most cases showed higher antioxidant and anti-diabetes potential than their corresponding O-glycosylflavonoids and aglycones. However, there is a lack of in vivo data on the biological benefits of flavonoid C-glycosides. It is necessary to investigate more on how flavonoid C-glycosides prevent and handle the diseases.
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Jaramillo Jaramillo, Carmita; Jaramillo Espinoza, Anyi; D'Armas, Haydelba; Troccoli, Luis; Rojas de Astudillo, Luisa
2016-09-01
Alkaloids, polyphenols, cyanogenic glycosides and saponins are among the main chemical compounds synthesized by plants but not considered essential for their basic metabolism. These compounds have different functions in plants, and have been recognized with medicinal and pharmacological properties. In this research, concentrations of the mentioned secondary metabolites were determined in the medicinal plants Artemisia absinthium, Cnidoscolus aconitifolius, Parthenium hysterophorus, Piper carpunya and Taraxacum officinale, from Ecuador, and related with cytotoxic effects against Artemia salina. Alcoholic and aqueous extracts from leaves of these selected plants were prepared at different concentrations. To assess cytotoxicity of these extracts, different bioassays with A. salina were undertaken, and the mortality rates and LC50 were obtained. Besides, concentrations of alkaloids, cyanogenic glycosides, phenols, tannins and saponins were determined by spectrophotometric methods; this constituted the first report of quantification of secondary metabolites in the selected plants from Ecuador. T. officinale had the highest concentration of total phenols (22.30 ± 0.23 mg/g) and tannins (11.70 ± 0.10 mg/g), C. aconitifolius of cyanogenic glycosides (5.02 ± 0.37 µg/g) and P. hysterophorus of saponins (6.12 ± 0.02 mg/g). Tannins values obtained were not adverse to their consumption. Alcoholic and aqueous extracts of selected plants had hemolytic activity depending on the concentration of saponins. Although the values of cyanogenic glycosides were permissible, it was necessary to monitor the presence of this metabolite in plants to minimize health problems. LC50 values ranged from extremely toxic (3.37 µg/mL) to highly toxic (274.34 μg/mL), in P. carpunya and T. officinale, respectively. From correlation analysis, it was observed that increase values of alkaloids concentrations had highly significant (p<0.001) acute toxicity against A. salina, while at a higher polyphenol concentration the level of plants cytotoxicity decreased significantly (p<0.001). The results of principal component analysis showed that saponins apparently were in synergy with polyphenols to decrease cytotoxicity, but antagonize with alkaloids and cyanogenic glycosides, indicating that these secondary metabolites present variability in the mechanisms of action against A. salina, as cytotoxic compounds. These results also demonstrate that polyphenols and saponins can be lethal at low concentrations, demonstrating the potential of brine shrimp bioassay as a model to evaluate plant extracts containing low concentrations of chemical compounds with high polarities. The significant positive correlation between cytotoxicity and concentration of alkaloids confirmed by the bioassay of brine shrimp can be useful to identify promising sources of antitumor compounds, and to evaluate tolerable limits not affecting other benign cells. Contents of secondary metabolites found in the selected plants confer them great pharmacologic values.
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Martemyanov, Vyacheslav V; Dubovskiy, Ivan M; Rantala, Markus J; Salminen, Juha-Pekka; Belousova, Irina A; Pavlushin, Sergey V; Bakhvalov, Stanislav A; Glupov, Victor V
2012-03-01
We tested the effects of defoliation-induced changes in silver birch, Betula pendula, foliar chemistry (delayed induced resistance, DIR) on the fitness and immune defense of the gypsy moth, Lymantria dispar. We measured larval developmental time, pupal weight, rate of survival to the adult stage, and five characteristics of larval immune defense: (1) encapsulation response; (2) phenoloxidase activity; (3) hemocyte concentration and (4) lysozyme-like activity in the hemolymph; and (5) resistance to infection by L. dispar nucleopolyhedrovirus (LdMNPV). The latter is an entomopathogenic baculovirus that often causes epizootics during outbreaks of L. dispar. We also measured the involvement of foliage non-tannin phenolic compounds in resistance of B. pendula to herbivory as well as the relationship between the compounds we identified and L. dispar development, growth, and survival. Leaves of B. pendula with previous defoliation history contained increased levels of myricetin glycoside, two flavonoid aglycones (acacetin and tetrahydroxy-flavone dimethyl ether), as well as one unidentified simple phenolic. The concentrations of two glycosides of quercetin, as well as the content of one unidentified flavonoid glycoside were significantly decreased under defoliation treatment. DIR of B. pendula retarded larval growth rate and increased lysozyme-like activity in the hemolymph, but did not affect encapsulation response, phenoloxidase activity, or hemocyte count. We did not find any DIR-mediated tritrophic interactions among birch, gypsy moth, and LdMNPV. After viral inoculation, the mean hemocyte counts in larvae reared on an individual tree correlated significantly with the survival of larvae reared on that same tree, indicating that hemocyte density in hemolymph might be associated with resistance to viral infection. We found a strong positive correlation between the concentration of 1-(4″-hydroxyphenyl)-3'-oxopropyl-β-D-glucopyranose and L. dispar survival rate, which may indicate an unlikely role of this dominant non-tannin phenolic in B. pendula defense against L. dispar. Our study also shows that several immune characteristics of insects that function as barriers against different groups of parasites are differently affected by plant induced defenses. This underscores the importance of considering multiple factors when characterizing barriers to insect immunity.
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Roberts, Shirley M; Davies, Gideon J
2012-01-01
The three-dimensional (3-D) structures of cellulases, and other glycoside hydrolases, are a central feature of research in carbohydrate chemistry and biochemistry. 3-D structure is used to inform protein engineering campaigns, both academic and industrial, which are typically used to improve the stability or activity of an enzyme. Examples of classical protein engineering goals include higher thermal stability, reduced metal-ion dependency, detergent and protease resistance, decreased product inhibition, and altered specificity. 3-D structure may also be used to interpret the behavior of enzyme variants that are derived from screening or random mutagenesis approaches, with a view to establishing an iterative design process. In other areas, 3-D structure is used as one of the many tools to probe enzymatic catalysis, typically dovetailing with physical organic chemistry approaches to provide complete reaction mechanisms for enzymes by visualizing catalytic site interactions at different stages of the reaction. Such mechanistic insight is not only fundamentally important, impacting on inhibitor and drug design approaches with ramifications way beyond cellulose hydrolysis, but also provides the framework for the design of enzyme variants to use as biocatalysts for the synthesis of bespoke oligosaccharides. Here we review some of the strategies and tactics that may be applied to the X-ray structure solution of cellulases (and other carbohydrate-active enzymes). The general approach is first to decide why you are doing the work, then to establish correct domain boundaries for truncated constructs (typically the catalytic domain only), and finally to pursue crystallization of pure, homogeneous, and monodisperse protein with appropriate ligand and additive combinations. Cellulase-specific strategies are important for the delineation of domain boundaries, while glycoside hydrolases generally also present challenges and opportunities for the selection and optimization of ligands to both aid crystallization, and also provide structural and mechanistic insight. As the many roles for plant cell wall degrading enzymes increase, so does the need for rapid high-quality structure determination to provide a sound structural foundation for understanding mechanism and specificity, and for future protein engineering strategies. Copyright © 2012 Elsevier Inc. All rights reserved.
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Chobot, Vladimir; Kubicova, Lenka; Bachmann, Gert; Hadacek, Franz
2013-01-01
Some antioxidants have been shown to possess additional pro-oxidant effects. Diverse methodologies exist for studying redox properties of synthetic and natural chemicals. The latter are substantial components of our diet. Exploration of their contribution to life-extending or -compromising effects is mandatory. Among reactive oxygen species (ROS), hydroxyl radical (•OH) is the most damaging species. Due to its short half-life, the assay has to contain a specific generation system. Plants synthesize flavonoids, phenolic compounds recognized as counter-agents to coronary heart disease. Their antioxidant activities are affected by their hydroxylation patterns. Moreover, in the plant, they mainly occur as glycosides. We chose three derivatives, quercetin, luteolin, and rutin, in attempts to explore their redox chemistry in contrasting hydrogen peroxide environments. Initial addition of hydrogen peroxide in high concentration or gradual development constituted a main factor affecting their redox chemical properties, especially in case of quercetin. Our study exemplifies that a combination of a chemical assay (deoxyribose degradation) with an electrochemical method (square-wave voltammetry) provides insightful data. The ambiguity of the tested flavonoids to act either as anti- or pro-oxidant may complicate categorization, but probably contributed to their evolution as components of a successful metabolic system that benefits both producer and consumer. PMID:23736691
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Chemistry, Pharmacology, and Toxicology of Khat (Catha Edulis Forsk): A Review
Wabe, Nasir Tajure
2011-01-01
Catha edulis (khat) is a plant grown commonly in the horn of Africa. The leaves of khat are chewed by the people for its stimulant action. Its young buds and tender leaves are chewed to attain a state of euphoria and stimulation. Khat is an evergreen shrub, which is cultivated as a bush or small tree. The leaves have an aromatic odor. The taste is astringent and slightly sweet. The plant is seedless and hardy, growing in a variety of climates and soils. Many different compounds are found in khat including alkaloids, terpenoids, flavonoids, sterols, glycosides, tannins, amino acids, vitamins and minerals. The phenylalkylamines and the cathedulins are the major alkaloids which are structurally related to amphetamine. The major effects of khat include those on the gastro-intestinal system and on the nervous system. Constipation, urine retention and acute cardiovascular effects may be regarded as autonomic (peripheral) nervous system effects; increased alertness, dependence, tolerance and psychiatric symptoms as effects on the central nervous system. The main toxic effects include increased blood pressure, tachycardia, insomnia, anorexia, constipation, general malaise, irritability, migraine and impaired sexual potency in men. Databases such as Pubmed, Medline, Hinary, Google search, Cochrane and Embase were systematically searched for literature on the different aspects of khat to summarize chemistry, pharmacology, toxicology of khat (Catha edulis Forsk). PMID:24494129
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Saracoglu, I; Inoue, M; Calis, I; Ogihara, Y
1995-10-01
Ten known glycosidic compounds, betulalbuside A (1), 8-hydroxylinaloyl,3-O-beta-D-glucopyranoside (2) (monoterpen glycosides), ipolamide (3) (iridoid glycoside), acteoside (verbascoside) (4), leucosceptoside A (5), martynoside (6), forsythoside B (7), phlinoside B (8), phlinoside C (9), and teuerioside (10) (phenylpropanoid glycosides) were isolated from methanolic extracts of Phlomis armeniaca and Scutellaria salviifolia (Labiatae). Structure elucidations were carried out using 1H-, 13C-NMR and FAB-MS spectra, as well as chemical evidence. The cytotoxic and cytostatic activities of isolated compounds were investigated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) method. Among the glycosides obtained here, caffeic acid-containing phenylpropanoid (or phenethyl alcohol, or phenylethanoid) glycosides were found to show activity against several kinds of cancer cells. However, they didn't affect the growth and viability of primary-cultured rat hepatocytes. Study of the structure-activity relationship indicated that ortho-dihydroxy aromatic systems of phenylpropanoid glycosides are necessary for their cytotoxic and cytostatic activities.
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A Review on the Pharmacology and Toxicology of Steviol Glycosides Extracted from Stevia rebaudiana.
Momtazi-Borojeni, Amir Abbas; Esmaeili, Seyed-Alireza; Abdollahi, Elham; Sahebkar, Amirhossein
2017-01-01
Stevia rebaudiana Bertoni is a sweet and nutrient-rich plant belonging to the Asteraceae family. Stevia leaves contain steviol glycosides including stevioside, rebaudioside (A to F), steviolbioside, and isosteviol, which are responsible for the plant's sweet taste, and have commercial value all over the world as a sugar substitute in foods, beverages and medicines. Among the various steviol glycosides, stevioside, rebaudioside A and rebaudioside C are the major metabolites and these compounds are on average 250-300 times sweeter than sucrose. Steviol is the final product of Stevia metabolism. The metabolized components essentially leave the body and there is no accumulation. Beyond their value as sweeteners, Stevia and its glycosdies possess therapeutic effects against several diseases such as cancer, diabetes mellitus, hypertension, inflammation, cystic fibrosis, obesity and tooth decay. Studies have shown that steviol glycosides found in Stevia are not teratogenic, mutagenic or carcinogenic and cause no acute and subacute toxicity. The present review provides a summary on the biological and pharmacological properties of steviol glycosides that might be relevant for the treatment of human diseases. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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Matsuo, Yosuke
2017-01-01
In recent years, plant polyphenols have attracted great attention due to their wide range of biological activities. Certain kinds of polyphenols have complex structures; therefore, it is difficult to elucidate their total structure, including stereochemistry. In this study, we reinvestigated the stereostructures of two major C-glycosidic ellagitannins contained in Quercus plants, vescalagin and castalagin, and revised their stereostructures based on theoretical calculations of spectroscopic data. We also determined the structures of quercusnins A and B, isolated from the sapwood of Quercus crispula, based on theoretical calculations of NMR data. The oxidation mechanism of polyphenols has not been entirely elucidated. Therefore, we have also studied the oxidation mechanism of tea catechins during black tea production. Our investigation of the oxidation mechanism of black tea pigment theaflavins revealed that the difference in the position of the galloyl ester affords different oxidation products of theaflavins. In addition, oxidation products of pyrogallol-type catechins could be classified into three types-dehydrotheasinensins, theacitrins, and proepitheaflagallins; their detailed production and degradation mechanisms were also examined.
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A new cinnamic acid glycoside from roots of Heracleum dissectum.
Wang, Zhi-Gang; Mi, Jie; Wang, Xin-Rui; Huo, Ya-Yu; Peng, Ya-Jie; Zhang, Hai-Min; Gao, Yang; Zhang, Hai-Long
2018-01-01
From the roots of Heracleum dissectum Lebb., one new cinnamic acid glycoside derivative named dissectumoside (1), together with eight known compounds including three phenolics, three phenolic glycosides and two phenylpropanoic glycoside were isolated using various chromatographic methods. Among them compound 2-9 was isolated from the plant for the first time. Their structures were elucidated and identified on the basis of their physicochemical properties and by extensive analyses of NMR spectroscopy and high-resolution mass spectrometry. The results of triglyceride accumulation screening in 3T3-L1 cells showed that compounds 1, 5 and 9 exhibited significantly accelerating activities of adipogenesis in adipocytes.
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Rechner, Ole; Neugart, Susanne; Schreiner, Monika; Wu, Sasa; Poehling, Hans-Michael
2017-01-01
Light of different wavelengths is essential for plant growth and development. Short-wavelength radiation such as UV can shift the composition of flavonoids, glucosinolates, and other plant metabolites responsible for enhanced defense against certain herbivorous insects. The intensity of light-induced, metabolite-based resistance is plant- and insect species-specific and depends on herbivore feeding guild and specialization. The increasing use of light-emitting diodes (LEDs) in horticultural plant production systems in protected environments enables the creation of tailor-made light scenarios for improved plant cultivation and induced defense against herbivorous insects. In this study, broccoli (Brassica oleracea var. italica) plants were grown in a climate chamber under broad spectra photosynthetic active radiation (PAR) and were additionally treated with the following narrow-bandwidth light generated with LEDs: UV-A (365 nm), violet (420 nm), blue (470 nm), or green (515 nm). We determined the influence of narrow-bandwidth light on broccoli plant growth, secondary plant metabolism (flavonol glycosides and glucosinolates), and plant-mediated light effects on the performance and behavior of the specialized cabbage aphid Brevicoryne brassicae. Green light increased plant height more than UV-A, violet, or blue LED treatments. Among flavonol glycosides, specific quercetin and kaempferol glycosides were increased under violet light. The concentration of 3-indolylmethyl glucosinolate in plants was increased by UV-A treatment. B. brassicae performance was not influenced by the different light qualities, but in host-choice tests, B. brassicae preferred previously blue-illuminated plants (but not UV-A-, violet-, or green-illuminated plants) over control plants.
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Neugart, Susanne; Schreiner, Monika; Wu, Sasa; Poehling, Hans-Michael
2017-01-01
Light of different wavelengths is essential for plant growth and development. Short-wavelength radiation such as UV can shift the composition of flavonoids, glucosinolates, and other plant metabolites responsible for enhanced defense against certain herbivorous insects. The intensity of light-induced, metabolite-based resistance is plant- and insect species-specific and depends on herbivore feeding guild and specialization. The increasing use of light-emitting diodes (LEDs) in horticultural plant production systems in protected environments enables the creation of tailor-made light scenarios for improved plant cultivation and induced defense against herbivorous insects. In this study, broccoli (Brassica oleracea var. italica) plants were grown in a climate chamber under broad spectra photosynthetic active radiation (PAR) and were additionally treated with the following narrow-bandwidth light generated with LEDs: UV-A (365 nm), violet (420 nm), blue (470 nm), or green (515 nm). We determined the influence of narrow-bandwidth light on broccoli plant growth, secondary plant metabolism (flavonol glycosides and glucosinolates), and plant-mediated light effects on the performance and behavior of the specialized cabbage aphid Brevicoryne brassicae. Green light increased plant height more than UV-A, violet, or blue LED treatments. Among flavonol glycosides, specific quercetin and kaempferol glycosides were increased under violet light. The concentration of 3-indolylmethyl glucosinolate in plants was increased by UV-A treatment. B. brassicae performance was not influenced by the different light qualities, but in host-choice tests, B. brassicae preferred previously blue-illuminated plants (but not UV-A-, violet-, or green-illuminated plants) over control plants. PMID:29190278
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Flavonol Glycosides from Gaura Biennis
USDA-ARS?s Scientific Manuscript database
Phytochemical investigation of the native American plant Gaura biennis led to the isolation of three new flavonol glycosides (1-3), along with eight known ones. Their structures were established primarily by spectroscopic data as quercetin 3-O-(2"-O-a-L-rhamnopyranosyl-6"-O-E-p-coumaroyl)-ß-D- gluco...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lindroth, R.L.; Kinney, K.K.
1998-10-01
Elevated concentrations of atmospheric CO{sub 2} are likely to interact with other factors affecting plant physiology to alter plant chemical profiles and plant-herbivore interactions. The authors evaluated the independent and interactive effects of enriched CO{sub 2} and artificial defoliation on foliar chemistry of quaking aspen (Populus tremuloides) and sugar maple (Acer saccharum), and the consequences of such changes for short-term performance of the gypsy moth (Lymantria dispar). They grew aspen and maple seedlings in ambient and enriched CO{sub 2} environments at the University of wisconsin Biotron. Seven weeks after budbreak, trees in half of the rooms were subjected to 50%more » defoliation. Afterwards, foliage was collected for chemical analyses, and feeding trials were conducted with fourth-stadium gypsy moths. Enriched CO{sub 2} altered foliar levels of water, nitrogen, carbohydrates, and phenolics, and responses generally differed between the two tree species. Defoliation induced chemical changes only in aspen. They found no significant interactions between CO{sub 2} and defoliation for levels of carbon-based defenses (phenolic glycosides and tannins). CO{sub 2} treatment altered the performance of larvae fed aspen, but not maple, whereas defoliation had little effect on performance on insects. In general, results from this experimental system do not support the hypothesis that induction of carbon-based chemical defenses, and attendant effects on insects, will be stronger in a CO{sub 2}-enriched world.« less
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Plant community diversity influences allocation to direct chemical defence in Plantago lanceolata.
Mraja, Anne; Unsicker, Sybille B; Reichelt, Michael; Gershenzon, Jonathan; Roscher, Christiane
2011-01-01
Forecasting the consequences of accelerating rates of changes in biodiversity for ecosystem functioning requires a mechanistic understanding of the relationships between the structure of biological communities and variation in plant functional characteristics. So far, experimental data of how plant species diversity influences the investment of individual plants in direct chemical defences against herbivores and pathogens is lacking. We used Plantago lanceolata as a model species in experimental grasslands differing in species richness and composition (Jena Experiment) to investigate foliar concentrations of the iridoid glycosides (IG), catalpol and its biosynthetic precursor aucubin. Total IG and aucubin concentrations decreased, while catalpol concentrations increased with increasing plant diversity in terms of species or functional group richness. Negative plant diversity effects on total IG and aucubin concentrations correlated with increasing specific leaf area of P. lanceolata, suggesting that greater allocation to light acquisition reduced the investment into these carbon-based defence components. In contrast, increasing leaf nitrogen concentrations best explained increasing concentrations of the biosynthetically more advanced IG, catalpol. Observed levels of leaf damage explained a significant proportion of variation in total IG and aucubin concentrations, but did not account for variance in catalpol concentrations. Our results clearly show that plants growing in communities of varying species richness and composition differ in their defensive chemistry, which may modulate plant susceptibility to enemy attack and consequently their interactions with higher trophic level organisms.
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[Sugar Chain Construction of Functional Natural Products Using Plant Glucosyltransferases].
Mizukami, Hajime
2015-01-01
Plant secondary product glycosyltransferases belong to family 1 of the glycosyltransferase superfamily and mediate the transfer of a glycosyl residue from activated nucleotide sugars to lipophilic small molecules, thus affecting the solubility, stability and pharmacological activities of the sugar-accepting compounds. The biotechnological application of plant glycosyltransferases in glycoside synthesis has attracted attention because enzymatic glycosylation offers several advantages over chemical methods, including (1) avoiding the use of harsh conditions and toxic catalysts, (2) providing strict control of regio-and stereo-selectivity and (3) high efficiency. This review describes the in vivo and in vitro glycosylation of natural organic compounds using glycosyltransferases, focusing on our investigation of enzymatic synthesis of curcumin glycosides. Our current efforts toward functional characterization of some glycosyltransferases involved in the biosynthesis of iridoids and crocin, as well as in the sugar chain elongation of quercetin glucosides, are described. Finally, I describe the relationship of the structure of sugar chains and the intestinal absorption which was investigated using chemoenzymatically synthesized quercetin glycosides.
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Fecalase: a model for activation of dietary glycosides to mutagens by intestinal flora
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tamura, G.; Gold, C.; Ferro-Luzzi, A.
1980-08-01
Many substances in the plant kingdom and in man's diet occur as glycosides. Recent studies have indicated that many glycosides that are not mutagenic in tests such as the Salmonella test become mutagenic upon hydrolysis of the glycosidic linkages. The Salmonella test utilizes a liver homogenate to approximate mammalian metabolism but does not provide a source of the enzymes present in intestinal bacterial flora that hydrolyze the wide variety of glycosides present in nature. We describe a stable cell-free extract of human feces, fecalase, which is shown to contain various glycosidases that allow the in vitro activation of many naturalmore » glycosides to mutagens in the Salmonella/liver homogenate test. Many beverages, such as red wine (but apparently not white wine) and tea, contain glycosides of the mutagen quercetin. Red wine, red grape juice, and teas were mutagenic in the test when fecalase was added, and red wine contained considerable direct mutagenic activity in the absence of fecalase. The implications of quercetin mutagenicity and carcinogenicity are discussed.« less
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Hjelmeland, Anna K; Zweigenbaum, Jerry; Ebeler, Susan E
2015-08-05
In this work we present a novel approach for the identification of plant metabolites using ultrahigh performance liquid chromatography coupled to accurate mass time-of-flight mass spectrometry. The workflow involves developing an in-house compound database consisting of exact masses of previously identified as well as putative compounds. The database is used to screen accurate mass spectrometry (MS) data to identify possible compound matches. Subsequent tandem MS data is acquired for possible matches and used for structural elucidation. The methodology is applied to profile monoterpene glycosides in Vitis vinifera cv. Muscat of Alexandria grape berries over three developmental stages. Monoterpenes are a subclass of terpenes, the largest class of plant secondary metabolites, and are found in two major forms in the plant, "bound" to one or more sugar moieties or "free" of said sugar moieties. In the free form, monoterpenes are noted for their fragrance and play important roles in plant defense and as attractants for pollinators. However, glycoconjugation renders these compounds odorless, and it is this form that the plant uses for monoterpene storage. In order to gain insight into monoterpene biochemistry and their fate in the plant an analysis of intact glycosides is essential. Eighteen monoterpene glycosides were identified including a monoterpene trisaccharide glycoside, which is tentatively identified here for this first time in any plant. Additionally, while previous studies have identified monoterpene malonylated glucosides in other grapevine tissue, we tentatively identify them for the first time in grape berries. This analytical approach can be readily applied to other plants and the workflow approach can also be used for other classes of compounds. This approach, in general, provides researchers with data to support the identification of putative compounds, which is especially useful when no standard is available. Copyright © 2015 Elsevier B.V. All rights reserved.
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Luck, Katrin; Jia, Qidong; Huber, Meret; Handrick, Vinzenz; Wong, Gane Ka-Shu; Nelson, David R; Chen, Feng; Gershenzon, Jonathan; Köllner, Tobias G
2017-09-01
Conifers contain P450 enzymes from the CYP79 family that are involved in cyanogenic glycoside biosynthesis. Cyanogenic glycosides are secondary plant compounds that are widespread in the plant kingdom. Their biosynthesis starts with the conversion of aromatic or aliphatic amino acids into their respective aldoximes, catalysed by N-hydroxylating cytochrome P450 monooxygenases (CYP) of the CYP79 family. While CYP79s are well known in angiosperms, their occurrence in gymnosperms and other plant divisions containing cyanogenic glycoside-producing plants has not been reported so far. We screened the transcriptomes of 72 conifer species to identify putative CYP79 genes in this plant division. From the seven resulting full-length genes, CYP79A118 from European yew (Taxus baccata) was chosen for further characterization. Recombinant CYP79A118 produced in yeast was able to convert L-tyrosine, L-tryptophan, and L-phenylalanine into p-hydroxyphenylacetaldoxime, indole-3-acetaldoxime, and phenylacetaldoxime, respectively. However, the kinetic parameters of the enzyme and transient expression of CYP79A118 in Nicotiana benthamiana indicate that L-tyrosine is the preferred substrate in vivo. Consistent with these findings, taxiphyllin, which is derived from L-tyrosine, was the only cyanogenic glycoside found in the different organs of T. baccata. Taxiphyllin showed highest accumulation in leaves and twigs, moderate accumulation in roots, and only trace accumulation in seeds and the aril. Quantitative real-time PCR revealed that CYP79A118 was expressed in plant organs rich in taxiphyllin. Our data show that CYP79s represent an ancient family of plant P450s that evolved prior to the separation of gymnosperms and angiosperms. CYP79A118 from T. baccata has typical CYP79 properties and its substrate specificity and spatial gene expression pattern suggest that the enzyme contributes to the formation of taxiphyllin in this plant species.
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Gu, L; Gu, W
2001-01-01
HPLC combined with electrospray ionisation (ESI)-MS and photodiode array detection has been employed to study the isoflavone components of soy. All of the known soy isoflavones separated by HPLC were identified and characterised, and three novel isoflavones were detected and screened out. These minor isoflavones were deduced to be isomers of 6"-O-malonyl isoflavone glycosides, based on the ESI-MS and UV data, in which the malonyl group is attached at a position other than the 6" position of the glycosyl moiety of the molecule. These novel malonyl glycosides are as thermally labile as the 6"-O-malonyl glycosides, being converted into known isoflavone glycosides after heating in aqueous ethanol. The advantages of HPLC-ESI-MS in detection of novel isoflavones from plant extracts are reviewed.
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Biosynthesis and regulation of cyanogenic glycoside production in forage plants.
Sun, Zhanmin; Zhang, Kaixuan; Chen, Cheng; Wu, Yanmin; Tang, Yixiong; Georgiev, Milen I; Zhang, Xinquan; Lin, Min; Zhou, Meiliang
2018-01-01
The natural products cyanogenic glycosides (CNglcs) are present in various forage plant species including Sorghum spp., Trifolium spp., and Lotus spp. The release of toxic hydrogen cyanide (HCN) from endogenous CNglcs, which is known as cyanogenesis, leads to a serious problem for animal consumption while as defensive secondary metabolites, CNglcs play multiple roles in plant development and responses to adverse environment. Therefore, it is highly important to fully uncover the molecular mechanisms of CNglc biosynthesis and regulation to manipulate the contents of CNglcs in forage plants for fine-tuning the balance between defensive responses and food safety. This review summarizes recent studies on the production, function, polymorphism, and regulation of CNglcs in forage plants, aiming to provide updated knowledge on the ways to manipulate CNglcs for further beneficial economic effects.
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Plant-derived cardiac glycosides: Role in heart ailments and cancer management.
Patel, Seema
2016-12-01
Cardiac glycosides, the cardiotonic steroids such as digitalis have been in use as heart ailment remedy since ages. They manipulate the renin-angiotensin axis to improve cardiac output. However; their safety and efficacy have come under scrutiny in recent times, as poisoning and accidental mortalities have been observed. In order to better understand and exploit them as cardiac ionotropes, studies are being pursued using different cardiac glycosides such as digitoxin, digoxin, ouabain, oleandrin etc. Several cardiac glycosides as peruvoside have shown promise in cancer control, especially ovary cancer and leukemia. Functional variability of these glycosides has revealed that not all cardiac glycosides are alike. Apart from their specific affinity to sodium-potassium ATPase, their therapeutic dosage and behavior in poly-morbidity conditions needs to be considered. This review presents a concise account of the key findings in recent years with adequate elaboration of the mechanisms. This compilation is expected to contribute towards management of cardiac, cancer, even viral ailments. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
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Saffron: An Old Medicinal Plant and a Potential Novel Functional Food.
José Bagur, María; Alonso Salinas, Gonzalo Luis; Jiménez-Monreal, Antonia M; Chaouqi, Soukaina; Llorens, Silvia; Martínez-Tomé, Magdalena; Alonso, Gonzalo L
2017-12-23
The spice saffron is made from the dried stigmas of the plant Crocus sativus L. The main use of saffron is in cooking, due to its ability to impart colour, flavour and aroma to foods and beverages. However, from time immemorial it has also been considered a medicinal plant because it possesses therapeutic properties, as illustrated in paintings found on the island of Santorini, dated 1627 BC. It is included in Catalogues of Medicinal Plants and in the European Pharmacopoeias, being part of a great number of compounded formulas from the 16th to the 20th centuries. The medicinal and pharmaceutical uses of this plant largely disappeared with the advent of synthetic chemistry-produced drugs. However, in recent years there has been growing interest in demonstrating saffron's already known bioactivity, which is attributed to the main components-crocetin and its glycosidic esters, called crocins, and safranal-and to the synergy between the compounds present in the spice. The objective of this work was to provide an updated and critical review of the research on the therapeutic properties of saffron, including activity on the nervous and cardiovascular systems, in the liver, its antidepressant, anxiolytic and antineoplastic properties, as well as its potential use as a functional food or nutraceutical.
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Potential anti-inflammatory phenolic glycosides from the medicinal plant Moringa oleifera fruits
USDA-ARS?s Scientific Manuscript database
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...
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A new withanolide glycoside from physalis peruviana
Ahmad; Malik; Afza; Yasmin
1999-03-01
A new withanolide glycoside, 17beta-hydroxy-14, 20-epoxy-1-oxo-[22R]-3beta-[O-beta-D-glucopyranosyl]-witha-5, 24-dienolide (1), has been isolated from the whole plant of Physalis peruviana. Its identity was determined using a combination of spectroscopic data including 2D NMR techniques and chemical transformations.
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Negm, S; El-Shabrawy, O; Arbid, M; Radwan, A S
1980-03-01
The acute toxicity of the alcoholic extracts of seeds, roots stems and leaves of the fully mature Corchorus olitorius L. plant was determined in mice by intraperitoneal injection. The cardiac glycosides content of each extract was estimated and the correlation between the two investigated parameters was established. The chronic toxicity of the alcoholic extract of the seeds was determined in term of its haematological and symptomatical effects on mice upon intraperitoneal injection for a period of two months.
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Chaturvedula, Venkata Sai Prakash; Prakash, Indra
2013-01-01
Catalytic hydrogenation of the exocyclic double bond present between C16 and C17 carbons of the four ent-kaurane diterpene glycosides namely rebaudioside A, rebaudioside B, rebaudioside C, and rebaudioside D isolated from Stevia rebaudiana has been carried out using Pt/C, Pd(OH)2, Rh/C, Raney Ni, PtO2, and 5% Pd/BaCO3 to their corresponding dihydro derivatives with 17α and 17β methyl group isomers. Reactions were performed using the above-mentioned catalysts with the solvents methanol, water, and ethanol/water (8:2) under various conditions. 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, including a comparison with reported spectral data. PMID:23896597
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Su, Xianming; Zhang, Jian; Li, Changkang; Li, Fenghua; Wang, Hongqing; Gu, Haifeng; Li, Baoming; Chen, Ruoyun; Kang, Jie
2018-05-11
Eight previously undescribed naphthohydroquinone glycosides, namely morindaparvins H-O, together with four known anthraquinone glycosides were isolated from the n-BuOH extract of the aerial parts of Morinda parvifolia Bartl. ex DC (Rubiaceae). The structures of morindaparvins H-O were elucidated on the basis of spectroscopic analysis. To our knowledge, this is the first isolation of quinone glycosides from the plant M. parvifolia. The results showed that all 12 compounds at the concentration of 50 μM significantly increased p53 mRNA expression in A2780 cells compared with the blank control group. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Putalun, Waraporn
2011-03-01
Single chain fragment-variable (scFv) enhanced solasodine glycoside accumulation in Solanum khasianum hairy root cultures transformed by the ScFv solamargine (As)-scFv gene. The scFv protein was expressed at a high level in inclusion bodies of E. coli. After being renatured, the scFv protein was purified in a one-step manner by metal chelate affinity chromatography. The yield of refolded and purified scFv was 12.5 mg per 100 ml of cell culture. The characteristics of the As-scFv expressed in E. coli and transgenic hairy roots were similar to those of the parent monoclonal antibody (MAb). The expression of scFv protein provides a low cost and a high yield of functional scFv antibody against solamargine. The full linear range of the ELISA assay using scFv was extended from 1.5-10 µg/ml. The expressed anti-solamargine scFv protein could be useful for determination of total solasodine glycoside content in plant samples by ELISA. Solasodine glycoside levels in the transgenic hairy root were 2.3-fold higher than that in the wild-type hairy root based on the soluble protein level and binding activities. The As-scFv expressed in S. khasianum hairy roots enhanced solasodine glycosides accumulation and provide a novel medicinal plant breeding methodology that can produce a high yield of secondary metabolites.
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Li, Yong; Wu, Xianfu; Li, Jianbei; Wang, Yinghong; Yu, Shishan; Lv, Haining; Qu, Jing; Abliz, Zeper; Liu, Jing; Liu, Yuanyan; Du, Dan
2010-02-01
Cardiac glycosides are a class of naturally occurring compounds that are characterized by some interesting biological activities and are widely distributed in the plant kingdom and can also be found in some animals. There is an interest in the chemical characterization of these molecules due to their toxicity and their use in medicines. In the study reported here, a combination of electrospray ionization tandem mass spectrometry with high-performance liquid chromatography equipped with diode-array detector (HPLC-DAD/ESI-MS(n)), and hyphenation to both liquid chromatography and nuclear magnetic resonance spectroscopy (HPLC/NMR) were utilized for the on-line analyses of cardiac glycosides from Periploca forrestii. The fragmentation patterns and (1)H NMR spectra of nine isolated cardiac glycosides were investigated; their fragmentation rules and (1)H NMR spectral characteristics were summarized and applied to the structural identification of similar constituents in fractions from P. forrestii. As a result, a total of nine trace cardiac glycosides were tentatively determined by analyses of accurate molecular masses, representative fragment ions and characteristic (1)H NMR signals provided by HPLC/high-resolution mass spectrometry (HRMS), HPLC-DAD/ESI-MS(n) and HPLC/(1)H NMR experiments, respectively. Of these, eight (2-9) are new compounds and one (1) is reported from P. forrestii for the first time. Results of the present study can benefit the rapid identification and targeted isolation of new cardiac glycosides from crude plant extracts. 2009 Elsevier B.V. All rights reserved.
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Jaiswal, Rakesh; Müller, Heiko; Müller, Anja; Karar, Mohamed Gamaleldin Elsadig; Kuhnert, Nikolai
2014-12-01
The chlorogenic acids, chlorogenic acid glycosides and flavonoids of the leaves of Lonicera henryi L. (Caprifoliaceae) were investigated qualitatively by liquid chromatography tandem mass spectrometry. Thirty-one chlorogenic acids and their glycosides were detected and characterized to their regioisomeric level on the basis of their unique fragmentation pattern in the negative ion mode tandem MS spectra. All of them were extracted for the first time from this source and thirteen of them were not reported previously in nature. For the positive identification of chlorogenic acid glycosides by LC-MS(n), multiple reaction monitoring and targeted MS(n) experiments were performed. We have developed an LC-MS(n) method for the systematic identification of chlorogenic acid glycosides and were also able to discriminate between chlorogenic acids and their isobaric glycosides. It was also possible to discriminate between 5-O-(3'-O-caffeoyl glucosyl)quinic acid and 5-O-(4'-O-caffeoyl glucosyl)quinic acid by LC-MS(n). This method can be applied for the rapid and positive identification of chlorogenic acids and their glycosides in plant materials, food and beverages. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Cai, Wenqing; Jiang, Linlin; Xie, Yafei; Liu, Yuqiang; Liu, Wei; Zhao, Guilong
2015-01-01
A brief history of the design of sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors is reviewed. The design of O-glucoside SGLT2 inhibitors by structural modification of phlorizin, a naturally occurring O-glucoside, in the early stage was a process mainly driven by biology with anticipation of improving SGLT2/SGLT1 selectivity and increasing metabolic stability. Discovery of dapagliflozin, a pioneering C-glucoside SGLT2 inhibitor developed by Bristol-Myers Squibb, represents an important milestone in this history. In the second stage, the design of C-glycoside SGLT2 inhibitors by modifications of the aglycone and glucose moiety of dapagliflozin, an original structural template for almost all C-glycoside SGLT2 inhibitors, was mainly driven by synthetic organic chemistry due to the challenge of designing dapagliflozin derivatives that are patentable, biologically active and synthetically accessible. Structure-activity relationships (SAR) of the SGLT2 inhibitors are also discussed.
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Orians, Colin M.; Fritz, Robert S.; Hochwender, Cris G.; Albrectsen, Benedicte R.; Czesak, Mary Ellen
2013-01-01
Background and Aims Selective feeding by herbivores, especially at the seedling or juvenile phase, has the potential to change plant traits and ultimately the susceptibility of surviving plants to other enemies. Moreover, since hybridization is important to speciation and can lead to introgression of traits between plant species, differential feeding (herbivore-induced mortality) can influence the expression of resistance traits of hybrids and ultimately determine the consequences of hybridization. While it would be expected that herbivore-induced mortality would lead to greater resistance, there may be trade-offs whereby resistance to one herbivore increases susceptibility to others. The hypothesis was tested that the exotic slug, Arion subfuscus, causes non-random survival of hybrid willows and alters plant: (1) susceptibility to slugs; (2) secondary and nutritional chemistry, and growth; and (3) susceptibility to other phytophages. Methods Two populations of plants, control and selected, were created by placing trays of juvenile willows in the field and allowing slugs access to only some. When ≤10 individuals/tray remained (approx. 85 % mortality), ‘selected’ and undamaged ‘control’ trays were returned to a common area. Traits of these populations were then examined in year 1 and in subsequent years. Key Results The selected population was less palatable to slugs. Surprisingly, foliar concentrations of putative defence traits (phenolic glycosides and tannins) did not differ between treatments, but the selected population had higher foliar nitrogen and protein, lower carbon to nitrogen ratio and greater above-ground biomass, indicating that vigorously growing plants were inherently more resistant to slugs. Interestingly, selected plants were more susceptible to three phytophages: an indigenous pathogen (Melampsora epitea), a native herbivorous beetle (Chrysomela knabi) and an exotic willow leaf beetle (Plagiodera versicolora). Conclusions This exotic slug changed the population structure of F2 hybrid willows in unanticipated ways. Defence expression remained unchanged, while nutritional and growth traits changed. These changes caused plants to be more susceptible to other plant enemies. Other exotic herbivore species are anticipated to have similar direct and indirect effects on native plant populations. PMID:23475954
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Jiao, Lijin; Tao, Yanduo; Wang, Weidong; Shao, Yun; Mei, Lijuan; Wang, Qilan; Dang, Jun
2017-10-01
An offline preparative two-dimensional reversed-phase liquid chromatography/hydrophilic interaction liquid chromatography coupled with hydrophilic interaction solid-phase extraction method was developed for the preparative isolation of flavonoid glycosides from a crude sample of Sphaerophysa salsula. First, the non-flavonoids were removed using an XAmide solid-phase extraction cartridge. Based on the separation results of three different chromatographic stationary phases, the first-dimensional preparation was performed on an XAqua C18 prep column, and 15 fractions were obtained from the 5.2 g target sample. Then, three representative fractions were selected for additional purification on an XAmide preparative column to further isolate the flavonoid glycosides. In all, eight flavonoid glycosides were isolated in purities over 97%. The results demonstrated that the two-dimensional liquid chromatography method used in this study was effective for the preparative separation of flavonoid glycosides from Sphaerophysa salsula. Additionally, this method showed great potential for the separation of flavonoid glycosides from other plant materials. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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USDA-ARS?s Scientific Manuscript database
Glycosylation often mediates important biological processes through the interaction of carbohydrates with complementary proteins. Most chemical tools for the functional analysis of glycans are highly dependent upon various linkage chemistries that involve the reducing-terminus of carbohydrates. Ho...
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Identification of natural products with neuronal and metabolic benefits through autophagy induction.
Fan, Yuying; Wang, Nan; Rocchi, Altea; Zhang, Weiran; Vassar, Robert; Zhou, Yifa; He, Congcong
2017-01-02
Autophagy is a housekeeping lysosomal degradation pathway important for cellular survival, homeostasis and function. Various disease models have shown that upregulation of autophagy may be beneficial to combat disease pathogenesis. However, despite several recently reported small-molecule screens for synthetic autophagy inducers, natural chemicals of diverse structures and functions have not been included in the synthetic libraries, and characterization of their roles in autophagy has been lacking. To discover novel autophagy-regulating compounds and study their therapeutic mechanisms, we used analytic chemistry approaches to isolate natural phytochemicals from a reservoir of medicinal plants used in traditional remedies. From this pilot plant metabolite library, we identified several novel autophagy-inducing phytochemicals, including Rg2. Rg2 is a steroid glycoside chemical that activates autophagy in an AMPK-ULK1-dependent and MTOR-independent manner. Induction of autophagy by Rg2 enhances the clearance of protein aggregates in a cell-based model, improves cognitive behaviors in a mouse model of Alzheimer disease, and prevents high-fat diet-induced insulin resistance. Thus, we discovered a series of autophagy-inducing phytochemicals from medicinal plants, and found that one of the compounds Rg2 mediates metabolic and neurotrophic effects dependent on activation of the autophagy pathway. These findings may help explain how medicinal plants exert the therapeutic functions against metabolic diseases.
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Neugart, Susanne; Fiol, Michaela; Schreiner, Monika; Rohn, Sascha; Zrenner, Rita; Kroh, Lothar W; Krumbein, Angelika
2014-05-07
Kale has a high number of structurally different flavonol glycosides and hydroxycinnamic acid derivatives. In this study we investigated the interaction of moderate UV-B radiation and temperature on these compounds. Kale plants were grown at daily mean temperatures of 5 or 15 °C and were exposed to five subsequent daily doses (each 0.25 kJ m(-2) d(-1)) of moderate UV-B radiation at 1 d intervals. Of 20 phenolic compounds, 11 were influenced by an interaction of UV-B radiation and temperature, e.g., monoacylated quercetin glycosides. Concomitantly, enhanced mRNA expression of flavonol 3'- hydroxylase showed an interaction of UV-B and temperature, highest at 0.75 kJ m(-2) and 15 °C. Kaempferol glycosides responded diversely and dependent on, e.g., the hydroxycinnamic acid residue. Compounds containing a catechol structure seem to be favored in the response to UV-B. Taken together, subsequent exposure to moderate UV-B radiation is a successful tool for enhancing the flavonoid profile of plants, and temperature should be considered.
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Sweet Poisons: Honeys Contaminated with Glycosides of the Neurotoxin Tutin.
Larsen, Lesley; Joyce, Nigel I; Sansom, Catherine E; Cooney, Janine M; Jensen, Dwayne J; Perry, Nigel B
2015-06-26
Poisonings due to consumption of honeys containing plant toxins have been reported widely. One cause is the neurotoxin tutin, an oxygenated sesquiterpene picrotoxane, traced back to honeybees (Apis mellifera) collecting honeydew produced by passionvine hoppers (Scolypopa australis) feeding on sap of the poisonous shrub tutu (Coriaria spp.). However, a pharmacokinetic study suggested that unidentified conjugates of tutin were also present in such honeys. We now report the discovery, using ion trap LC-MS, of two tutin glycosides and their purification and structure determination as 2-(β-d-glucopyranosyl)tutin (4) and 2-[6'-(α-d-glucopyranosyl)-β-d-glucopyranosyl]tutin (5). These compounds were used to develop a quantitative triple quadrupole LC-MS method for honey analysis, which showed the presence of tutin (3.6 ± 0.1 μg/g honey), hyenanchin (19.3 ± 0.5), tutin glycoside (4) (4.9 ± 0.4), and tutin diglycoside (5) (4.9 ± 0.1) in one toxic honey. The ratios of 4 and 5 to tutin varied widely in other tutin-containing honeys. The glycosidation of tutin may represent detoxification by one or both of the insects involved in the food chain from plant to honey.
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Sarvin, Boris; Fedorova, Elizaveta; Shpigun, Oleg; Titova, Maria; Nikitin, Mikhail; Kochkin, Dmitry; Rodin, Igor; Stavrianidi, Andrey
2018-03-30
In this paper, the ultrasound assisted extraction method for isolation of steroidal glycosides from D. deltoidea plant cell suspension culture with a subsequent HPLC-MS determination was developed. After the organic solvent was selected via a two-factor experiment the optimization via Latin Square 4 × 4 experimental design was carried out for the following parameters: extraction time, organic solvent concentration in extraction solution and the ratio of solvent to sample. It was also shown that the ultrasound assisted extraction method is not suitable for isolation of steroidal glycosides from the D. deltoidea plant material. The results were double-checked using the multiple successive extraction method and refluxing extraction. Optimal conditions for the extraction of steroidal glycosides by the ultrasound assisted extraction method were: extraction time, 60 min; acetonitrile (water) concentration in extraction solution, 50%; the ratio of solvent to sample, 400 mL/g. Also, the developed method was tested on D. deltoidea cell suspension cultures of different terms and conditions of cultivation. The completeness of the extraction was confirmed using the multiple successive extraction method. Copyright © 2018 Elsevier B.V. All rights reserved.
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Esmaeili, Fatemeh; Ghaheri, Matin; Kahrizi, Danial; Mansouri, Mohsen; Safavi, Seyed Mehdi; Ghorbani, Tayebeh; Muhammadi, Sarre; Rahmanian, Elham; Vaziri, Siavash
2018-02-10
Stevia rebaudiana Bertoni is one of the most important biologically sourced and low-calorie sweeteners that contains a lots of Steviol glycosides. Tissue culture is the best method for propagation of stevia and micro nutrients can affect both morphological traits and steviol glycosides production. In the present study, we investigated the effect of different concentrations of glutamine (10, 20, 30 and 40 g/l) on expression of UGT74G1 and UGT76G1 genes and stevioside and rebaudioside A accumulation in the leaves of stevia under in vitro conditions. The highest level of expression for UGT74G1 (1.000 Total lab unit) was seen at plants grown in MS media without glutamine and the highest gene expression level for UGT76G1 (1.321 Total lab unit) was observed at plants grown in 2% glutamine. Based on HPLC results, the highest amount of stevioside (22.74) was accumulated in plants which were under 3% glutamine treatment and the lowest production level of stevioside (16.19) was resulted under MS (0 glutamine) medium. The highest rebaudioside A (12.19) accumulation was observed under 2% glutamine treatment and the lowest accumulation of rebaudioside A (8.41) was seen at plants grown in MS medium.
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Resin glycoside constituents of Ipomoea pes-caprae (beach morning glory).
Tao, Hongwen; Hao, Xiaojiang; Liu, Jinggen; Ding, Jian; Fang, Yuchun; Gu, Qianqun; Zhu, Weiming
2008-12-01
Eight new resin glycosides, pescapreins X-XVII (1-8), were isolated from a lipophilic fraction of an ethanol extract of the entire plant of beach morning glory, Ipomoea pes-caprae. Their structures were elucidated by spectroscopic data analysis and by chemical transformation. These compounds were evaluated biologically in terms of cancer cell line cytotoxicity, antibacterial and antifungal activity, and effects on the mu-opioid receptor.
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Cytotoxic cardiac glycosides and other compounds from Asclepias syriaca.
Araya, Juan J; Kindscher, Kelly; Timmermann, Barbara N
2012-03-23
Phytochemical investigation of the dried biomass of Asclepias syriaca afforded five new compounds (1-5), along with 19 known structures. Overall, the secondary metabolites isolated and identified from this plant showed a wide structural diversity including pentacyclic triterpenes, cardiac glycosides, flavonoid glycosides, lignans, a phenylethanoid, and a glycosylated megastigmane. In addition, the isolates were tested against the cancer breast cell line Hs578T, and those showing IC(50) values lower than 50 μM (1 and 6-9) were further investigated in three additional breast cancer cell lines (MCF-7, T47D, and Sk-Br-3) and the normal breast cell line Hs578Bst.
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Warashina, Tsutomu; Umehara, Kaoru; Miyase, Toshio; Noro, Tadataka
2011-10-01
A pregnane glycoside fraction from the roots of Asclepias tuberosa L. caused normal human skin fibroblasts to proliferate. This fraction contained 21 pregnane glycosides whose structures were established using NMR spectroscopic analysis and chemical evidence. The aglycones of most of these compounds were identified as 8,12;8,20-diepoxy-8,14-secopregnanes, such as tuberogenin or 5,6-didehydrotuberogenin, the same aglycones as constituents of the aerial parts of this plant. Some of these compounds also caused proliferation of skin fibroblasts. Copyright © 2011 Elsevier Ltd. All rights reserved.
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The occurrence of tricin and its derivatives in plants
Li, Mi; Pu, Yunqiao; Yoo, Chang Geun; ...
2016-02-02
Our understanding of the structure and biosynthetic pathway of lignin, a phenylpropanoid heteropolymer, continues to evolve, especially with the discovery of new lignin monomers/structural moieties such as monolignol acetate, hydroxycinnamyl aldehyde/alcohol, and p-hydroxybenzoate in the past decades. Recently, tricin has been reported as a component incorporated into monocot lignin. As a flavonoid compound widely distributed in herbaceous plants, tricin has been extensively studied due to its biological significance in plant growth as well as its potential for pharmaceutical importance. Tricin is biosynthesized as a constituent of plant secondary metabolites through a combination of phenylpropanoid and polyketide pathways. Tricin occurs inmore » plants in either free or conjugated forms such as tricin-glycosides, tricin-lignans, and tricin-lignan-glycosides.The emergence of tricin covalently incorporated with lignin biopolymer implies the possible association of lignification and tricin biosynthesis. This review summarizes the occurrence of tricin and its derivatives in plants. Additionally, synthesis, potential application, and characterization of tricin are discussed.« less
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The occurrence of tricin and its derivatives in plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Mi; Pu, Yunqiao; Yoo, Chang Geun
Our understanding of the structure and biosynthetic pathway of lignin, a phenylpropanoid heteropolymer, continues to evolve, especially with the discovery of new lignin monomers/structural moieties such as monolignol acetate, hydroxycinnamyl aldehyde/alcohol, and p-hydroxybenzoate in the past decades. Recently, tricin has been reported as a component incorporated into monocot lignin. As a flavonoid compound widely distributed in herbaceous plants, tricin has been extensively studied due to its biological significance in plant growth as well as its potential for pharmaceutical importance. Tricin is biosynthesized as a constituent of plant secondary metabolites through a combination of phenylpropanoid and polyketide pathways. Tricin occurs inmore » plants in either free or conjugated forms such as tricin-glycosides, tricin-lignans, and tricin-lignan-glycosides.The emergence of tricin covalently incorporated with lignin biopolymer implies the possible association of lignification and tricin biosynthesis. This review summarizes the occurrence of tricin and its derivatives in plants. Additionally, synthesis, potential application, and characterization of tricin are discussed.« less
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Quantification of flavonol glycosides in Camellia sinensis by MRM mode of UPLC-QQQ-MS/MS.
Wu, Yahui; Jiang, Xiaolan; Zhang, Shuxiang; Dai, Xinlong; Liu, Yajun; Tan, Huarong; Gao, Liping; Xia, Tao
2016-04-01
Phenolic compounds are major components of tea flavour, in which catechins and flavonol glycosides play important roles in the astringent taste of tea infusion. However, the flavonol glycosides are difficult to quantify because of the large variety, as well as the inefficient seperation on chromatography. In this paper, a total of 15 flavonol glycosides in the tea plant (Camellia sinensis) were identified by the high performance liquid chromatography (HPLC) coupled to a time-of-flight mass spectrometer (TOF-MS), and a quantitative method was established based on multiple reaction monitoring (MRM) mode of ultra-high performance liquid chromatography (UPLC) coupled to a triple quadrupole mass spectrometer (QQQ-MS/MS). It provided the limit of detection and quantification to the order of picogram, which was more sensitive than the HPLC detection of the order of nanogram. The relative standard deviations of the intra- and inter-day variations in retention time and signal intensity (peak area) of six analytes were less than 0.26% and 4%, respectively. The flavonol glycosides of four tea cultivars were relatively quantified using the signal intensity (peak area) of product ion, in which six flavonol glycosides were quantified by the authentic standards. The results showed that the flavonol mono-, di- and tri-glycoside mostly accumulated in young leaves of the four tea cultivars. Notably, the myricetin 3-O-galactoside was the major component among the six flavonol glycosides detected. Copyright © 2016 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Stone, Bruce A.; Svensson, Birte; Collins, Michelle E.; Rastall, Robert A.
An overview of current and potential enzymes used to degrade polysaccharides is presented. Such depolymerases are comprised of glycoside hydrolases, glycosyl transferases, phosphorylases and lyases, and their classification, active sites and action patterns are discussed. Additionally, the mechanisms that these enzymes use to cleave glycosidic linkages is reviewed as are inhibitors of depolymerase activity; reagents which react with amino acid residues, glycoside derivatives, transition state inhibitors and proteinaceous inhibitors. The characterization of various enzymes of microbial, animal or plant origin has led to their widespread use in the production of important oligosaccharides which can be incorporated into food stuffs. Sources of polysaccharides of particular interest in this chapter are those from plants and include inulin, dextran, xylan and pectin, as their hydrolysis products are purported to be functional foods in the context of gastrointestinal health. An alternative use of degraded polysaccharides is in the treatment of disease. The possibility exists to treat bacterial exopolysaccharide with lyases from bacteriophage to produce oligosaccharides exhibiting bioactive sequences. Although this area is currently in its infancy the knowledge is available to investigate further.
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Tiberti, Luciana A; Yariwake, Janete H; Ndjoko, Karine; Hostettmann, Kurt
2007-02-01
A comparative analysis of the flavonoid components of the leaves of two medicinal plants known in Brazil as "espinheira santa", namely, Maytenus ilicifolia Mart. ex Reiss. and M. aquifolium Mart. (Celastraceae), and a hybrid plant, M. aquifoliumxM. ilicifolia, has been carried out using high-performance liquid chromatography coupled with photodiode array UV detection and mass spectrometry. One methoxyflavonoid glycoside and 18 flavonol-3-O-glycosides were identified in the extracts on the basis of their on-line UV spectra (measured in the absence and presence of shift reagents) and multiple stage mass spectral data. Fingerprint analysis of the flavonoid extracts revealed significant differences in the profiles of the two Maytenus species, while the hybrid plant contained flavonoids found in both parent species.
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Morikawa, Toshio; Zhang, Yi; Nakamura, Seikou; Matsuda, Hisashi; Muraoka, Osamu; Yoshikawa, Masayuki
2007-03-01
Six new megastigmane glycosides, sedumosides E1, E2, E3, F1, F2, and G, were isolated from the whole plant of Sedum sarmentosum (Crassulaceae). The structures of new constituents including the absolute configuration were elucidated on the basis of chemical and physicochemical evidence.
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Degradations and Rearrangement Reactions
NASA Astrophysics Data System (ADS)
Zhang, Jianbo
This section deals with recent reports concerning degradation and rearrangement reactions of free sugars as well as some glycosides. The transformations are classified in chemical and enzymatic ways. In addition, the Maillard reaction will be discussed as an example of degradation and rearrangement transformation and its application in current research in the fields of chemistry and biology.
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Kim, Min Kyoung; Yun, Kwang Jun; Lim, Da Hae; Kim, Jinju; Jang, Young Pyo
2016-01-01
The chemical components and biological activity of Camellia mistletoe, Korthalsella japonica (Loranthaceae) are relatively unknown compared to other mistletoe species. Therefore, we investigated the phytochemical properties and biological activity of this parasitic plant to provide essential preliminary scientific evidence to support and encourage its further pharmaceutical research and development. The major plant components were chromatographically isolated using high-performance liquid chromatography and their structures were elucidated using tandem mass spectrometry and nuclear magnetic resonance anlysis. Furthermore, the anti-inflammatory activity of the 70% ethanol extract of K. japonica (KJ) and its isolated components was evaluated using a nitric oxide (NO) assay and western blot analysis for inducible NO synthase (iNOS) and cyclooxygenase (COX)-2. Three flavone di-C-glycosides, lucenin-2, vicenin-2, and stellarin-2 were identified as major components of KJ, for the first time. KJ significantly inhibited NO production and reduced iNOS and COX-2 expression in lipopolysaccharide-stimulated RAW 264.7 cells at 100 μg/mL while similar activity were observed with isolated flavone C-glycosides. In conclusion, KJ has a simple secondary metabolite profiles including flavone di-C-glycosides as major components and has a strong potential for further research and development as a source of therapeutic anti-inflammatory agents. PMID:27302962
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Yoshida, Takashi; Amakura, Yoshiaki; Yoshimura, Morio
2010-01-01
Plant tannins, including hydrolysable and condensed varieties, are well known antioxidants in medicinal plants, foods, and edible fruits. Their diverse biological properties and potential for disease prevention have been demonstrated by various in vitro and in vivo assays. A number of ellagitannins, the largest group of hydrolysable tannins, have been isolated from dicotyledoneous angiosperms and characterized. This diverse class of tannins is sub-grouped into simple ellagitannins, C-glycosidic ellagitannins, complex tannins (condensates of C-glycosidic tannins with flavan-3-ol), and oligomers up to pentamers. This review outlines and describes the chemotaxonomic significance of structural features in various types of ellagitannins found in plants belonging to the Myrtaceae, Onagraceae, and Melastomataceae families, which are all included in the order Myrtales. Any biological activities that have been reported, including antitumor and antibacterial effects as well as enzyme inhibition, are also reviewed. PMID:20162003
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Biological and Phytopharmacological Descriptions of Litchi Chinensis.
Kilari, Eswar Kumar; Putta, Swathi
2016-01-01
Plants remain a vital source of drugs and at present, much emphasis is given to nutraceuticals. Herbal medicines have been the basis of treatment and cure for various diseases and physiological conditions in the traditional methods practiced such as ayurveda and homeopathy. Litchi chinensis belongs to the Sapindaceae family and is well-known in the Indian traditional system for its traditional uses. The parts of the plant used are leaves, flowers, fruits, seed, pulp, and pericarp. All parts of the plant are rich sources of phytochemicals--epicatechin; procyanidin A2 and procyanidin B2; leucocyanidin; cyanidin glycoside, malvidin glycoside, and saponins; butylated hydroxytoluene; isolariciresinol; kaempferol; rutin; and stigmasterol. In the present review, we explore the lychee's description, traditional medicinal uses, and phytoconstituents, and investigate the pharmacological activities in various parts of the lychee to show its importance in ethanopharmacology. This is so that this review can serve as a ready-to-use material for further research on the plant.
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Zhou, Li; Xu, Jin-Di; Zhou, Shan-Shan; Shen, Hong; Mao, Qian; Kong, Ming; Zou, Ye-Ting; Xu, Ya-Yun; Xu, Jun; Li, Song-Lin
2017-12-29
Exploring processing chemistry, in particular the chemical transformation mechanisms involved, is a key step to elucidate the scientific basis in traditional processing of herbal medicines. Previously, taking Rehmanniae Radix (RR) as a case study, the holistic chemome (secondary metabolome and glycome) difference between raw and processed RR was revealed by integrating hyphenated chromatographic techniques-based targeted glycomics and untargeted metabolomics. Nevertheless, the complex chemical transformation mechanisms underpinning the holistic chemome variation in RR processing remain to be extensively clarified. As a continuous study, here a novel strategy by combining chemomics-based marker compounds mining and mimetic processing is proposed for further exploring the chemical mechanisms involved in herbal processing. First, the differential marker compounds between raw and processed herbs were rapidly discovered by untargeted chemomics-based mining approach through multivariate statistical analysis of the chemome data obtained by integrated metabolomics and glycomics analysis. Second, the marker compounds were mimetically processed under the simulated physicochemical conditions as in the herb processing, and the final reaction products were chemically characterized by targeted chemomics-based mining approach. Third, the main chemical transformation mechanisms involved were clarified by linking up the original marker compounds and their mimetic processing products. Using this strategy, a set of differential marker compounds including saccharides, glycosides and furfurals in raw and processed RR was rapidly found, and the major chemical mechanisms involved in RR processing were elucidated as stepwise transformations of saccharides (polysaccharides, oligosaccharides and monosaccharides) and glycosides (iridoid glycosides and phenethylalcohol glycosides) into furfurals (glycosylated/non-glycosylated hydroxymethylfurfurals) by deglycosylation and/or dehydration. The research deliverables indicated that the proposed strategy could advance the understanding of RR processing chemistry, and therefore may be considered a promising approach for delving into the scientific basis in traditional processing of herbal medicines. Copyright © 2017 Elsevier B.V. All rights reserved.
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Potential Health Risks Posed by Plant-Derived Cumulative Neurotoxic Bufadienolides in South Africa.
Botha, Christo
2016-03-16
Bufadienolide-type cardiac glycosides have a worldwide distribution and are mainly synthesized by plants, but there are also animal sources. In South Africa, members of three genera of the Crassulaceae (Cotyledon, Tylecodon and Kalanchoe) cause a unique chronic form of cardiac glycoside poisoning, predominantly in small stock. This paretic/paralytic condition is referred to as "krimpsiekte", cotyledonosis or "nenta". "Krimpsiekte" is a plant poisoning only reported from South Africa and is regarded as the most important plant poisoning of small stock in the semi-arid Little Karoo and southern fringes of the Great Karoo. The toxicosis is caused by cumulative bufadienolides which have neurotoxic properties. Four types of cumulative neurotoxic bufadienolides, namely cotyledoside, and the tyledosides, orbicusides and lanceotoxins, have been isolated. Based on the structure activity relationships and certain toxicokinetic parameters possible reasons for their accumulation are presented. Consumption of edible tissues from animals that have ingested these plants poses a potential risk to humans.
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Tothiam, Charinrat; Phrompittayarat, Watoo; Putalun, Waraporn; Tanaka, Hiroyuki; Sakamoto, Seiichi; Khan, Ikhlas A; Ingkaninan, Kornkanok
2011-01-01
In Ayurvedic medicines, Bacopa monnieri (L.) Wettst. (brahmi) is known as a medicinal plant used for memory enhancement. Its active compounds are classified as pseudojujubogenin and jujubogenin glycosides. Owing to the lack of chromophore in the saponin glycoside structures, HPLC-UV-vis gives low sensitivity for determination of such compounds. In the case of the detection of small amounts of saponin glycosides, immunological assay could be a suitable method. To develop and validate a sensitive enzyme-linked immunosorbant assay (ELISA) using monoclonal antibody (MAb) against bacoside A₃, the major jujubogenin glycoside found in brahmi. An immunogen was prepared by conjugating bacoside A₃ with a bovine serum albumin (BSA). To determine its immunogenicity, the ratio of hapten in bacoside A₃-BSA conjugate was determined by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). After immunisation in mice, hybridomas secreting MAbs against bacoside A₃ were produced by fusing the immunised splenocytes with SP2/0- Ag14 myeloma cells. The antibody was raised specifically against jujubogenin glycosides. The ELISA using anti-bacoside A₃ MAb was developed. Bacoside A₃ in the range of 3.05-97.70 ng mL⁻¹ could be detected by ELISA using anti-bacoside A₃ MAb. The assay showed a detection limit of 0.48 ng mL⁻¹ (0.517 nm). The validation study showed that the method was precise, accurate and sensitive. Interestingly, the MAb showed cross-reactivity with the other jujubogenin glycosides, bacopaside X and IV. However, it did not show cross-reactivity with any of pseudojujubogenin glycosides. The study demonstrated that ELISA using anti-bacoside A₃ MAb can be used for determination of total jujubogenin glycosides in brahmi. Copyright © 2011 John Wiley & Sons, Ltd.
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Natural toxins of plant origin (phytotoxins)
USDA-ARS?s Scientific Manuscript database
Over 100,000 secondary compounds have been identified in plants including alkaloids, glycosides, proteins, polypeptides, amines and non-protein amino acids, organic acids, alcohols, polyacetylenes, resinous toxins and mineral toxins. For thousands of years man has used some of these compounds as fl...
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ERIC Educational Resources Information Center
Periyannan, Gopal R.; Lawrence, Barbara A.; Egan, Annie E.
2015-01-01
A [superscript 1]H NMR spectroscopy-based laboratory experiment explores mono- and disaccharide structural chemistry, and the enzyme-substrate specificity of glycosidic bond cleavage by ß-glucosidase towards cellobiose (ß-linked gluco-disaccharide) and maltose (a-linked gluco-disaccharide). Structural differences between cellobiose, maltose, and…
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USDA-ARS?s Scientific Manuscript database
In natural product chemistry, it is often crucial to determine sugar composition as well as the absolute configuration of each monosaccharide in glycosides. An ultra-performance liquid chromatography method using both photodiode array (PDA) and mass spectrometry detectors (UPLC-UV/MS) was developed....
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USDA-ARS?s Scientific Manuscript database
Phytosterols (plant sterols) occur in the cells of all plants. They are important structural components that stabilize the biological membranes of plants. Sterols can occur in the “free” unbound form or they can be covalently bound via an ester or glycosidic bond. Since our previous 2002 review o...
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USDA-ARS?s Scientific Manuscript database
Introduction- Mycorrhizae symbiosis is a universal phenomenon in nature that promotes plant growth and food quality in most plants, especially, under phosphorus deficiency and water stress. Objective- The objective of this study was to assess the effects of mycorrhizal symbiosis on changes in the le...
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Two new phenylpropanoid glycosides with interesterification from Scrophularia dentata Royle ex Benth
NASA Astrophysics Data System (ADS)
Zhang, Liuqiang; Yang, Zhuo; Jia, Qi; Dorje, Gaawe; Zhao, Zhili; Guo, Fujiang; Li, Yiming
2013-10-01
Two new phenylpropanoid glycosides (1-2), along with seven known ones (3-9), were isolated from the whole plant of Scrophularia dentata Royle ex Benth. Their structures were elucidated by spectroscopic methods. Among them, compounds 1 and 2 failed to separated, because they can easily transform into each other by acyl migrant reaction. In this paper, the interesterification mechanism was discussed firstly and the rule can be used in the similar structure elucidation in future.
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Dynamic changes in plant secondary metabolites during UV acclimation in Arabidopsis thaliana.
Hectors, Kathleen; Van Oevelen, Sandra; Geuns, Jan; Guisez, Yves; Jansen, Marcel A K; Prinsen, Els
2014-10-01
Plants respond to environmental stress by synthesizing a range of secondary metabolites for defense purposes. Here we report on the effect of chronic ultraviolet (UV) radiation on the accumulation of plant secondary metabolites in Arabidopsis thaliana leaves. In the natural environment, UV is a highly dynamic environmental parameter and therefore we hypothesized that plants are continuously readjusting levels of secondary metabolites. Our data show distinct kinetic profiles for accumulation of tocopherols, polyamines and flavonoids upon UV acclimation. The lipid-soluble antioxidant α-tocopherol accumulated fast and remained elevated. Polyamines accumulated fast and transiently. This fast response implies a role for α-tocopherol and polyamines in short-term UV response. In contrast, an additional sustained accumulation of flavonols took place. The distinct accumulation patterns of these secondary metabolites confirm that the UV acclimation process is a dynamic process, and indicates that commonly used single time-point analyses do not reveal the full extent of UV acclimation. We demonstrate that UV stimulates the accumulation of specific flavonol glycosides, i.e. kaempferol and (to a lesser extent) quercetin di- and triglycosides, all specifically rhamnosylated at position seven. All metabolites were identified by Ultra Performance Liquid Chromatography (UPLC)-coupled tandem mass spectrometry. Some of these flavonol glycosides reached steady-state levels in 3-4 days, while concentrations of others are still increasing after 12 days of UV exposure. A biochemical pathway for these glycosides is postulated involving 7-O-rhamnosylation for the synthesis of all eight metabolites identified. We postulate that this 7-O-rhamnosylation has an important function in UV acclimation. © 2014 Scandinavian Plant Physiology Society.
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Antioxidant constituents of the aerial parts of Globularia alypum growing in Morocco.
Es-Safi, Nour-Eddine; Khlifi, Samira; Kerhoas, Lucien; Kollmann, Albert; El Abbouyi, Ahmed; Ducrot, Paul-Henri
2005-08-01
Three new phenolic compounds were isolated from the aerial parts of Globularia alypum. Their structures were determined as 6-hydroxyluteolin 7-O-laminaribioside (1), eriodictyol 7-O-sophoroside (2), and 6'-O-coumaroyl-1'-O-[2-(3,4-dihydroxyphenyl)ethyl]-beta-D-glucopyranoside (3). In addition, three phenylethanoid glycosides (acteoside, isoacteoside, and forsythiaside) and two flavonoid glycosides (6-hydroxyluteolin 7-O-beta-D-glucopyranoside and luteolin 7-O-sophoroside) were also isolated and are reported here for the first time in this plant. The structures of compounds 1-3 were established on the basis of their spectroscopic data analysis. Evaluation of the antioxidative activity, conducted in vitro, showed that the isolated phenylethanoids and flavonoid glycosides possess strong effects of this type.
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Agati, Giovanni; Stefano, Giovanni; Biricolti, Stefano; Tattini, Massimiliano
2009-10-01
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. 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. 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. 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.
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Agati, Giovanni; Stefano, Giovanni; Biricolti, Stefano; Tattini, Massimiliano
2009-01-01
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
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Beg, Sarwar; Swain, Suryakanta; Hasan, Hameed; Barkat, M Abul; Hussain, Md Sarfaraz
2011-01-01
Many synthetic drugs reported to be used for the treatment of inflammatory disorders are of least interest now a days due to their potential side effects and serious adverse effects and as they are found to be highly unsafe for human assistance. Since the last few decades, herbal drugs have regained their popularity in treatment against several human ailments. Herbals containing anti-inflammatory activity (AIA) are topics of immense interest due to the absence of several problems in them, which are associated with synthetic preparations. The primary objective of this review is to provide a deep overview of the recently explored anti-inflammatory agents belonging to various classes of phytoconstituents like alkaloids, glycosides, terpenoids, steroids, polyphenolic compounds, and also the compounds isolated from plants of marine origin, algae and fungi. Also, it enlists a distended view on potential interactions between herbals and synthetic preparations, related adverse effects and clinical trials done on herbals for exploring their AIA. The basic aim of this review is to give updated knowledge regarding plants which will be valuable for the scientists working in the field of anti-inflammatory natural chemistry. PMID:22279370
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Phenylpropanoid Scent Compounds in Petunia x hybrida Are Glycosylated and Accumulate in Vacuoles
Cna'ani, Alon; Shavit, Reut; Ravid, Jasmin; Aravena-Calvo, Javiera; Skaliter, Oded; Masci, Tania; Vainstein, Alexander
2017-01-01
Floral scent has been studied extensively in the model plant Petunia. However, little is known about the intracellular fate of scent compounds. Here, we characterize the glycosylation of phenylpropanoid scent compounds in Petunia x hybrida. This modification reduces scent compounds' volatility, reactivity, and autotoxicity while increasing their water-solubility. Gas chromatography–mass spectrometry (GC–MS) analyses revealed that flowers of petunia cultivars accumulate substantial amounts of glycosylated scent compounds and that their increasing level parallels flower development. In contrast to the pool of accumulated aglycones, which drops considerably at the beginning of the light period, the collective pool of glycosides starts to increase at that time and does not decrease thereafter. The glycoside pool is dynamic and is generated or catabolized during peak scent emission, as inferred from phenylalanine isotope-feeding experiments. Using several approaches, we show that phenylpropanoid scent compounds are stored as glycosides in the vacuoles of petal cells: ectopic expression of Aspergillus niger β-glucosidase-1 targeted to the vacuole resulted in decreased glycoside accumulation; GC–MS analysis of intact vacuoles isolated from petal protoplasts revealed the presence of glycosylated scent compounds. Accumulation of glycosides in the vacuoles seems to be a common mechanism for phenylpropanoid metabolites. PMID:29163617
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A new pregnane glycoside from Rubus phoenicolasius and its antiproliferative activity.
Liu, Chao; Liao, Zhi-Xin; Liu, Shi-Jun; Sun, Jin-Yue; Yao, Gui-Yang; Wang, Heng-Shan
2014-01-01
Chemical investigations of the whole plant ethanol extract of Rubus phoenicolasius led to the isolation and identification of a new pregnane glycoside, 3-O-β-glucopyranosyl-3β,15β-dihydroxypregn-5-en-20-one (1), along with other nine known compounds (2-10). All the isolates were reported from this plant for the first time. The structure of compound 1 was determined by detailed analysis of its spectral data including 1D and 2D NMR. In vitro anti-proliferative activities of compounds 1-3 on MCF-7 and NCI-H460 tumour cell lines were evaluated, and compound 1 was active against the two cell lines with IC50 values of 15.6 and 13.5 μM, respectively.
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A new aurone glycoside with antifungal activity from marine-derived fungus Penicillium sp. FJ-1.
Song, Yan-xia; Ma, Qiang; Li, Jie
2015-03-01
Endophytic fungi which reside in the tissue of mangrove plants seem to play an important role in the discovery of new biologically active substances. During the course of screening for the antimicrobial metabolites from the endophytic fugus Penicillium sp. FJ-1 of mangrove plant Avicennia marina, a new aurone glycoside (1) was isolated by repeated column chromatography on silica gel and recrystallization methods. The structure of 1 was elucidated as (Z)-7,4'-dimethoxy-6-hydroxy-aurone-4-O-β-glucopyranoside, on the basis of spectroscopic analysis. Compound 1 exhibited antifungal activity against Candida sp., with the potency comparable to amphotericin B and much better than fluconazole. Compound 1 can also inhibit extracellular phospholipase secretion in a concentration-dependent manner.
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Yadava, R N; Saurabh, K
1998-01-01
Tridax procumbens Linn. (N.O. Compositae) is commonly known as Tikki Kasa in Hindi. It is distributed throughout in India up to 2400 m above sea level and in all hot countries. The present paper deals with the isolation and identification of a new flavone glycoside, 5,7,4'-trihydroxy-6,3'-dimethoxy-flavone 5-O-alpha-L-rhamnopyranoside 1, from the leaves of this plant.
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Emerging roles for conjugated sterols in plants.
Ferrer, Albert; Altabella, Teresa; Arró, Montserrat; Boronat, Albert
2017-07-01
In plants, sterols are found in free form (free sterols, FSs) and conjugated as steryl esters (SEs), steryl glycosides (SGs) and acyl steryl glycosides (ASGs). Conjugated sterols are ubiquitously found in plants but their relative contents highly differ among species and their profile may change in response to developmental and environmental cues. SEs play a central role in membrane sterol homeostasis and also represent a storage pool of sterols in particular plant tissues. SGs and ASGs are main components of the plant plasma membrane (PM) that specifically accumulate in lipid rafts, PM microdomains known to mediate many relevant cellular processes. There are increasing evidences supporting the involvement of conjugated sterols in plant stress responses. In spite of this, very little is known about their metabolism. At present, only a limited number of genes encoding enzymes participating in conjugated sterol metabolism have been cloned and characterized in plants. The aim of this review is to update the current knowledge about the tissue and cellular distribution of conjugated sterols in plants and the enzymes involved in their biosynthesis. We also discuss novel aspects on the role of conjugated sterols in plant development and stress responses recently unveiled using forward- and reverse-genetic approaches. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Phytochemical constituents of some Indian medicinal plants.
Dhandapani, R; Sabna, B
2008-04-01
Alkaloids, tannins, saponins, steroid, terpenoid, flavonoids, phlobatannin and cardie glycoside distribution in seven medicinal plants belonging to different families were assessed and compared. The medicinal plants investigated were Aegle marmelos, Cynodon dactylon, Eclipta prostrata, Moringa pterygosperma, Pongamia pinnata, Sida acuta and Tridax procumbens. The significance of the plants in traditional medicine and the importance of the distribution of these chemical constituents were discussed with respect to the role of these plants in ethnomedicine in India.
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Mark Scriber, J
1978-01-01
Two genotypes (one cyanogenic and the other acyanogenic) of birds-foot trefoil, Lotus corniculatus L., were used to study the effects of cyanogenic glycosides in leaf tissues upon a polyphagous herbivore, the southern armyworm, Spodoptera eridania Cram. (Lepidoptera). No differences were observed in consumption rate, assimilation efficiency, utilization of plant biomass, or metabolic costs in terms of expended calories between larvae fed acyanogenic or cyanogenic leaves. Similarly no differences were seen in the nitrogen or caloric utilization efficiencies, or in the nitrogen accumulation rate or growth rate of larvae on cyanogenic versus acyanogenic plants. Larval performance and growth on 20-week old plants was generally poorer than on 4 week old plants, however. This was reflected in slower growth, smaller pupal weights, lower nitrogen utilization efficiencies (N.U.E.) and biomass assimilation efficiencies (A.D.) on both the cyanogenic and acyanogenic plants.Although useful as a deterrent to some herbivores, cyanogenesis does not seem to provide an effective defense against this "adapted" herbivore. This study supports current hypotheses of insect/plant coevolution, and suggests that the metabolic costs of processing cyanogenic plant biomass are small in comparison to those imposed by the nutritional status of the plant leaves.
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Brulc, Jennifer M; Antonopoulos, Dionysios A; Miller, Margret E Berg; Wilson, Melissa K; Yannarell, Anthony C; Dinsdale, Elizabeth A; Edwards, Robert E; Frank, Edward D; Emerson, Joanne B; Wacklin, Pirjo; Coutinho, Pedro M; Henrissat, Bernard; Nelson, Karen E; White, Bryan A
2009-02-10
The complex microbiome of the rumen functions as an effective system for the conversion of plant cell wall biomass to microbial protein, short chain fatty acids, and gases. As such, it provides a unique genetic resource for plant cell wall degrading microbial enzymes that could be used in the production of biofuels. The rumen and gastrointestinal tract harbor a dense and complex microbiome. To gain a greater understanding of the ecology and metabolic potential of this microbiome, we used comparative metagenomics (phylotype analysis and SEED subsystems-based annotations) to examine randomly sampled pyrosequence data from 3 fiber-adherent microbiomes and 1 pooled liquid sample (a mixture of the liquid microbiome fractions from the same bovine rumens). Even though the 3 animals were fed the same diet, the community structure, predicted phylotype, and metabolic potentials in the rumen were markedly different with respect to nutrient utilization. A comparison of the glycoside hydrolase and cellulosome functional genes revealed that in the rumen microbiome, initial colonization of fiber appears to be by organisms possessing enzymes that attack the easily available side chains of complex plant polysaccharides and not the more recalcitrant main chains, especially cellulose. Furthermore, when compared with the termite hindgut microbiome, there are fundamental differences in the glycoside hydrolase content that appear to be diet driven for either the bovine rumen (forages and legumes) or the termite hindgut (wood).
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ERIC Educational Resources Information Center
Herdman, Chelsea; Diop, Lamine; Dickman, Michael
2013-01-01
Carbohydrate analysis is an excellent way to expose second-year biochemistry majors to the subtlety and nuance of sugar chemistry. In one, 3-h practical period, students must identify an unknown mono- or disaccharide from a collection of three hexoses (glucose, galactose, and mannose), two pentoses (ribose and arabinose), and three disaccharides…
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Phytochemical constituents of some Indian medicinal plants
Dhandapani, R.; Sabna, B.
2008-01-01
Alkaloids, tannins, saponins, steroid, terpenoid, flavonoids, phlobatannin and cardie glycoside distribution in seven medicinal plants belonging to different families were assessed and compared. The medicinal plants investigated were Aegle marmelos, Cynodon dactylon, Eclipta prostrata, Moringa pterygosperma, Pongamia pinnata, Sida acuta and Tridax procumbens. The significance of the plants in traditional medicine and the importance of the distribution of these chemical constituents were discussed with respect to the role of these plants in ethnomedicine in India. PMID:22557280
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Munafo, John P; Gianfagna, Thomas J
2011-06-08
Botrytis cinerea Pers. Fr. is a plant pathogenic fungus and the causal organism of blossom blight of Easter lily (Lilium longiflorum Thunb.). Easter lily is a rich source of steroidal glycosides, compounds which may play a role in the plant-pathogen interaction of Easter lily. Five steroidal glycosides, including two steroidal glycoalkaloids and three furostanol saponins, were isolated from L. longiflorum and evaluated for fungal growth inhibition activity against B. cinerea, using an in vitro plate assay. All of the compounds showed fungal growth inhibition activity; however, the natural acetylation of C-6''' of the terminal glucose in the steroidal glycoalkaloid, (22R,25R)-spirosol-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→2)-[6-O-acetyl-β-D-glucopyranosyl-(1→4)]-β-D-glucopyranoside (2), increased antifungal activity by inhibiting the rate of metabolism of the compound by B. cinerea. Acetylation of the glycoalkaloid may be a plant defense response to the evolution of detoxifying mechanisms by the pathogen. The biotransformation of the steroidal glycoalkaloids by B. cinerea led to the isolation and characterization of several fungal metabolites. The fungal metabolites that were generated in the model system were also identified in Easter lily tissues infected with the fungus by LC-MS. In addition, a steroidal glycoalkaloid, (22R,25R)-spirosol-5-en-3β-yl O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (6), was identified as both a fungal metabolite of the steroidal glycoalkaloids and as a natural product in L. longiflorum for the first time.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Walker, Johnnie A.; Pattathil, Sivakumar; Bergeman, Lai F.
Glycoside hydrolases (GHs) are enzymes that hydrolyze polysaccharides into simple sugars. To better understand the specificity of enzyme hydrolysis within the complex matrix of polysaccharides found in the plant cell wall, we studied the reactions of individual enzymes using glycome profiling, where a comprehensive collection of cell wall glycan-directed monoclonal antibodies are used to detect polysaccharide epitopes remaining in the walls after enzyme treatment and quantitative nanostructure initiator mass spectrometry (oxime-NIMS) to determine soluble sugar products of their reactions. Single, purified enzymes from the GH5_4, GH10, and GH11 families of glycoside hydrolases hydrolyzed hemicelluloses as evidenced by the loss ofmore » specific epitopes from the glycome profiles in enzyme-treated plant biomass. The glycome profiling data were further substantiated by oxime-NIMS, which identified hexose products from hydrolysis of cellulose, and pentose-only and mixed hexose-pentose products from the hydrolysis of hemicelluloses. The GH10 enzyme proved to be reactive with the broadest diversity of xylose-backbone polysaccharide epitopes, but was incapable of reacting with glucose-backbone polysaccharides. In contrast, the GH5 and GH11 enzymes studied here showed the ability to react with both glucose- and xylose-backbone polysaccharides. The identification of enzyme specificity for a wide diversity of polysaccharide structures provided by glycome profiling, and the correlated identification of soluble oligosaccharide hydrolysis products provided by oxime-NIMS, offers a unique combination to understand the hydrolytic capabilities and constraints of individual enzymes as they interact with plant biomass.« less
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Walker, Johnnie A.; Pattathil, Sivakumar; Bergeman, Lai F.; ...
2017-02-02
Glycoside hydrolases (GHs) are enzymes that hydrolyze polysaccharides into simple sugars. To better understand the specificity of enzyme hydrolysis within the complex matrix of polysaccharides found in the plant cell wall, we studied the reactions of individual enzymes using glycome profiling, where a comprehensive collection of cell wall glycan-directed monoclonal antibodies are used to detect polysaccharide epitopes remaining in the walls after enzyme treatment and quantitative nanostructure initiator mass spectrometry (oxime-NIMS) to determine soluble sugar products of their reactions. Single, purified enzymes from the GH5_4, GH10, and GH11 families of glycoside hydrolases hydrolyzed hemicelluloses as evidenced by the loss ofmore » specific epitopes from the glycome profiles in enzyme-treated plant biomass. The glycome profiling data were further substantiated by oxime-NIMS, which identified hexose products from hydrolysis of cellulose, and pentose-only and mixed hexose-pentose products from the hydrolysis of hemicelluloses. The GH10 enzyme proved to be reactive with the broadest diversity of xylose-backbone polysaccharide epitopes, but was incapable of reacting with glucose-backbone polysaccharides. In contrast, the GH5 and GH11 enzymes studied here showed the ability to react with both glucose- and xylose-backbone polysaccharides. The identification of enzyme specificity for a wide diversity of polysaccharide structures provided by glycome profiling, and the correlated identification of soluble oligosaccharide hydrolysis products provided by oxime-NIMS, offers a unique combination to understand the hydrolytic capabilities and constraints of individual enzymes as they interact with plant biomass.« less
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Cyanogenic glycosides in plant-based foods available in New Zealand.
Cressey, Peter; Saunders, Darren; Goodman, Janet
2013-01-01
Cyanogenic glycosides occur in a wide range of plant species. The potential toxicity of cyanogenic glycosides arises from enzymatic degradation to produce hydrogen cyanide, which may result in acute cyanide poisoning and has also been implicated in the aetiology of several chronic diseases. One hundred retail foods were sampled and analysed for the presence of total hydrocyanic acid using an acid hydrolysis-isonicotinic/barbituric acid colourimetric method. Food samples included cassava, bamboo shoots, almonds and almond products, pome fruit products, flaxseed/linseed, stone fruit products, lima beans, and various seeds and miscellaneous products, including taro leaves, passion fruit, spinach and canned stuffed vine leaves. The concentrations of total hydrocyanic acid (the hydrocyanic acid equivalents of all cyanogenic compounds) found were consistent with or lower than concentrations reported in the scientific literature. Linseed/flaxseed contained the highest concentrations of total hydrocyanic acid of any of the analysed foods (91-178 mg kg(-1)). Linseed-containing breads were found to contain total hydrocyanic acid at concentrations expected from their linseed content, indicating little impact of processing on the total hydrocyanic acid content. Simulation modelling was used to assess the risk due to the total hydrocyanic acid in fruit juice and linseed-containing bread.
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Nhiem, Nguyen Xuan; Yen, Pham Hai; Ngan, Nguyen Thi Thanh; Quang, Tran Hong; Kiem, Phan Van; Minh, Chau Van; Tai, Bui Huu; Cuong, Nguyen Xuan; Song, Seok Bean
2012-01-01
Abstract Momordica charantia: is used to treat various diseases, including inflammatory conditions. Previous reports indicated that the extract of this plant inhibits activation of nuclear transcription factor-κB (NF-κB) but activates peroxisome proliferator-activated receptor (PPAR). Additionally, cucurbitane-type triterpene glycosides are the main bioactive components of the fruit of M. charantia. Therefore, we investigated the anti-inflammatory activity of 17 cucurbitane-type triterpene glycosides (1–17) isolated from this plant. Their inhibition of NF-κB and activation of PPAR activities in HepG2 cells were measured using luciferase reporter and PPAR subtype transactivation assays. Compounds 6 and 8 were found to inhibit NF-κB activation stimulated by tumor necrosis factor-α (TNFα) in a dose-dependent manner. With 50% inhibition concentration (IC50) values of 0.4 μM, compounds 6 and 8 were more potent inhibitors than the positive control, sulfasalazine (IC50=0.9 μM). Compounds 4, 6, and 8 also inhibited TNFα-induced expressions of inducible nitric oxide synthase and cyclooxygenase-2 mRNA. However, only compound 13 significantly increased PPARγ transactivation. PMID:22248180
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NASA Astrophysics Data System (ADS)
Aranda-González, Irma; Betancur-Ancona, David; Chel-Guerrero, Luis; Moguel-Ordóñez, Yolanda
2017-01-01
Drying techniques can modify the composition of certain plant compounds. Therefore, the aim of the study was to assess the effect of different drying methods on steviol glycosides in Stevia rebaudiana Bertoni leaves. Four different drying methods were applied to Stevia rebaudiana Bertoni leaves, which were then subjected to aqueous extraction. Radiation or convection drying was performed in stoves at 60°C, whereas shade or sun drying methods were applied at 29.7°C and 70% of relative humidity. Stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, dulcoside A, and steviolbioside were quantified by a validated HPLC method. Among steviol glycosides, the content (g 100 g-1 dry basis) of stevioside, rebaudioside A, rebaudioside B, and rebaudioside C varied according to the drying method. The total glycoside content was higher in sun-dried samples, with no significant differences compared to shade or convection drying, whereas radiation drying adversely affected the content of rebaudioside A and rebaudioside C (p <0.01) and was therefore a method lowering total glycoside content. The effect of the different drying methods was also reflected in the proportion of the sweetener profile. Convection drying could be suitable for modern food processing industries while shadow or sun drying may be a low-cost alternative for farmers.
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Knittel, Diana N; Stintzing, Florian C; Kammerer, Dietmar R
2015-06-10
Sea squill (Drimia maritima L.) extracts have been used for centuries for the medical treatment of heart diseases. A procedure for the preparation of Drimia extracts applied for such purposes comprising a fermentation step is described in the German Homoeopathic Pharmacopoeia (GHP). However, little is known about the secondary metabolite profile of such extracts and the fate of these components upon processing and storage. Thus, in the present study sea squill extracts were monitored during fermentation and storage by HPLC-DAD-MS(n) and GC-MS to characterise and quantitate individual cardiac glycosides and phenolic compounds. For this purpose, a previously established HPLC method for the separation and quantitation of pharmacologically relevant cardiac glycosides (bufadienolides) was validated. Within 12 months of storage, total bufadienolide contents decreased by about 50%, which was attributed to microbial and plant enzyme activities. The metabolisation and degradation rates of individual bufadienolide glycosides significantly differed, which was attributed to differing structures of the aglycones. Further degradation of bufadienolide aglycones was also observed. Besides reactions well known from human metabolism studies, dehydration of individual compounds was monitored. Quantitatively predominating flavonoids were also metabolised throughout the fermentation process. The present study provides valuable information about the profile and stability of individual cardiac glycosides and phenolic compounds in fermented Drimia extracts prepared for medical applications, and expands the knowledge of cardiac glycoside conversion upon microbial fermentation. Copyright © 2015 Elsevier B.V. All rights reserved.
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Barnaba, C; Dellacassa, E; Nicolini, G; Nardin, T; Serra, M; Larcher, R
2018-07-06
Many metabolites naturally occur as glycosides, since sugar moieties can be crucial for their biological activity and increase their water solubility. In the plant kingdom they may occur as glycosides or sugar esters, depending on precursor chemical structure, and in wine they have traditionally attracted attention due to their organoleptic properties, such as astringency and bitterness, and because they affect the colour and aroma of wines. A new approach directed at detailed description of glycosides in a large selection of monovarietal wines (8 samples each of Pinot Blanc, Muller Thurgau, Riesling, Traminer, Merlot, Pinot Noir and Cabernet Sauvignon) was developed by combining high performance liquid chromatography with high resolution tandem mass spectrometry. Analytical separation was performed on an Accucore™ Polar Premium LC column, while mass analysis was performed in negative ion mode with an non-targeted screening approach, using a Full MS/AIF/NL dd-MS 2 experiment at a resolving power of 140,000 FWHM. Over 280 glycoside-like compounds were detected, of which 133 (including low-molecular weight phenols, flavonoids and monoterpenols) were tentatively identified in the form of pentose (6), deoxyhexose (17), hexose (73), hexose-pentose (16), hexose-deoxyhexose (7), dihexose (5) and hexose ester (9) derivatives. It was not possible to univocally define the corresponding chemical structure for the remaining 149 glycosides. Non-parametric statistical analysis showed it was possible to well characterise the glycosylated profile of all red and Traminer wines, while the identified glycosides were almost entirely lacking in Pinot Blanc, Riesling and Muller Thurgau wines. Also Tukey's Honestly Significant Difference test (p < 0.05) and Principal Component Analysis confirmed that it was possible to almost entirely distinguish the selected red wines from each other according to their glycosylated profile. Copyright © 2018 Elsevier B.V. All rights reserved.
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Host plant associated enhancement of immunity and survival in virus infected caterpillars.
Smilanich, Angela M; Langus, Tara C; Doan, Lydia; Dyer, Lee A; Harrison, Joshua G; Hsueh, Jennifer; Teglas, Mike B
2018-01-01
Understanding the interaction between host plant chemistry, the immune response, and insect pathogens can shed light on host plant use by insect herbivores. In this study, we focused on how interactions between the insect immune response and plant secondary metabolites affect the response to a viral pathogen. Based upon prior research, we asked whether the buckeye caterpillar, Junonia coenia (Nymphalidae), which specializes on plants containing iridoid glycosides (IGs), is less able to resist the pathogenic effects of a densovirus infection when feeding on plants with high concentrations of IGs. In a fully factorial design, individuals were randomly assigned to three treatments, each of which had two levels: (1) exposed to the densovirus versus control, (2) placed on a plant species with high concentrations of IGs (Plantago lanceolata, Plantaginaceae) versus low concentrations of IGs (P. major), and (3) control versus surface sterilized to exclude surface microbes that may contribute to viral resistance. We measured phenoloxidase (PO) activity, hemocyte counts, and gut bacterial diversity (16S ribosomal RNA) during the fourth larval instar, as well as development time, pupal weight, and survival to adult. Individuals infected with the virus were immune-suppressed (as measured by PO response and hemocyte count) and developed significantly faster than virus-free individuals. Contrary to our predictions,mortality was significantly less for virus challengedindividuals reared on the high IG plant compared to the low IG plant.This suggests that plant secondary metabolites can influence survival from viral infection and may be associated with activation of PO. Removing egg microbes did not affect the immune response or survival of the larvae. In summary, these results suggest that plant secondary metabolites are important for survival against a viral pathogen. Even though the PO response was better on the high IG plant, the extent to which this result contributes to survival against the virus needs further investigation. Copyright © 2017 Elsevier Inc. All rights reserved.
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First Report of Peronospora digitalidis causing downy mildew disease on foxglove in Oregon
USDA-ARS?s Scientific Manuscript database
Foxglove (Digitalis purpurea) is a biennial plant in the Plantaginaceae family. Widely cultivated as a striking flowering ornamental plant, foxglove is also a source of toxic cardiac glycosides that may be fatal if ingested at high doses, or used pharmaceutically to treat human heart failure. In the...
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Lin, Long-Ze; Sun, Jianghao; Chen, Pei; Harnly, James
2013-01-01
An UHPLC-PDA-ESI/HRMS/MSn profiling method was used for a comprehensive study of the phenolic components of red mustard greens (Brassica juncea Coss variety) and identified 67 anthocyanins, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives. The glycosylation patterns of the flavonoids were assigned on the basis of direct comparison of the parent flavonoid glycosides with reference compounds. The putative identifications were obtained from tandem mass data analysis and confirmed by the retention time, elution order, and UV–vis and high-resolution mass spectra. Further identifications were made by comparing the UHPLC-PDA-ESI/HRMS/MSn data with those of reference compounds in the polyphenol database and in the literature. Twenty-seven acylated cyanidin 3-sophoroside-5-diglucosides, 24 acylated cyanidin 3-sophoroside-5- glucosides, 3 acylated cyanidin triglucoside-5-glucosides, 37 flavonol glycosides, and 10 hydroxycinnamic acid derivatives were detected for the first time in brassica vegetables. At least 50 of them are reported for the first time in any plant materials. PMID:21970730
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Foxglove poisoning most often occurs from sucking the flowers or eating the seeds, stems, or leaves of ... The poisonous substances are found in: Flowers, leaves, stems, and seeds of the foxglove plant Heart medicine (digitalis glycoside)
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2011-01-01
Background Lignocellulosic materials have been moved towards the forefront of the biofuel industry as a sustainable resource. However, saccharification and the production of bioproducts derived from plant cell wall biomass are complex and lengthy processes. The understanding of termite gut biology and feeding strategies may improve the current state of biomass conversion technology and bioproduct production. Results The study herein shows comprehensive functional characterization of crude body extracts from Coptotermes gestroi along with global proteomic analysis of the termite's digestome, targeting the identification of glycoside hydrolases and accessory proteins responsible for plant biomass conversion. The crude protein extract from C. gestroi was enzymatically efficient over a broad pH range on a series of natural polysaccharides, formed by glucose-, xylose-, mannan- and/or arabinose-containing polymers, linked by various types of glycosidic bonds, as well as ramification types. Our proteomic approach successfully identified a large number of relevant polypeptides in the C. gestroi digestome. A total of 55 different proteins were identified and classified into 29 CAZy families. Based on the total number of peptides identified, the majority of components found in the C. gestroi digestome were cellulose-degrading enzymes. Xylanolytic enzymes, mannan- hydrolytic enzymes, pectinases and starch-degrading and debranching enzymes were also identified. Our strategy enabled validation of liquid chromatography with tandem mass spectrometry recognized proteins, by enzymatic functional assays and by following the degradation products of specific 8-amino-1,3,6-pyrenetrisulfonic acid labeled oligosaccharides through capillary zone electrophoresis. Conclusions Here we describe the first global study on the enzymatic repertoire involved in plant polysaccharide degradation by the lower termite C. gestroi. The biochemical characterization of whole body termite extracts evidenced their ability to cleave all types of glycosidic bonds present in plant polysaccharides. The comprehensive proteomic analysis, revealed a complete collection of hydrolytic enzymes including cellulases (GH1, GH3, GH5, GH7, GH9 and CBM 6), hemicellulases (GH2, GH10, GH11, GH16, GH43 and CBM 27) and pectinases (GH28 and GH29). PMID:22081966
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Apoptotic activities of cardenolide glycosides from Asclepias subulata.
Rascón-Valenzuela, L A; Velázquez, C; Garibay-Escobar, A; Vilegas, W; Medina-Juárez, L A; Gámez-Meza, N; Robles-Zepeda, R E
2016-12-04
Asclepias subulata Decne. (Apocynaceae) is a shrub occurring in Sonora-Arizona desert. The ethnic groups of Sonora, Mexico, Seris and Pimas, use this plant for the treatment of sore eyes, gastrointestinal disorders and cancer. To determine the cell death pathways that the cardenolide glycosides with antiproliferative activity found in the methanol extract of A. subulata are able to activate. The effect of cardenolide glycosides isolated of A. subulata on induction of apoptosis in cancer cells was evaluated through the measuring of several key events of apoptosis. A549 cells were treated for 12h with doses of 3.0, 0.2, 3.0 and 1.0µM of 12, 16-dihydroxicalotropin, calotropin, corotoxigenin 3-O-glucopyranoside and desglucouzarin, respectively. Apoptotic and necrotic cell levels were measured by double staining with annexin V-FITC/PI. Mitochondrial membrane depolarization was examined through JC-1 staining. Apoptosis cell death and the apoptosis pathways activated by cardenolide glycosides isolated of A. subulata were further characterized by the measurement of caspase-3, caspase-8 and caspase-9 activity. Apoptotic assays showed that the four cardenolide glycosides isolated of A. subulata induced apoptosis in A549 cells, which was evidencing by phosphatidylserine externalization in 18.2%, 17.0%, 23.9% and 22.0% for 12, 16-dihydroxicalotropin, calotropin, corotoxigenin 3-O-glucopyranoside and desglucouzarin, respectively, compared with 4.6% of control cells. Cell death was also associated with a decrease in mitochondrial membrane potential, which was more than 75% in the treated cultures respect to control. The activation of caspase-3 was observed in all cardenolide glycosides-treated cancer cells indicating the caspase-dependent apoptosis of A549 cells. Extrinsic and intrinsic apoptosis pathways were activated by cardenolide glycosides treatment at the doses tested. In this study was found that cardenolide glycosides, 12, 16-dihydroxicalotropin, calotropin, corotoxigenin 3-O-glucopyranoside and desglucouzarin, isolated from A. subulata induced the cell death trough caspase-dependent apoptosis, which was activated, preferably, by extrinsic pathway. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
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Exploring the functional significance of sterol glycosyltransferase enzymes.
Singh, Gaurav; Dhar, Yogeshwar Vikram; Asif, Mehar Hasan; Misra, Pratibha
2018-01-01
Steroidal alkaloids (SAs) are widely synthesized and distributed in plants manifesting as natural produce endowed with potential for medicinal, pesticidal and other high-value usages. Glycosylation of these SAs raises complex and diverse glycosides in plant cells that indeed govern numerous functional aspects. During the glycosylation process of these valuable metabolites, the addition of carbohydrate molecule(s) is catalyzed by enzymes known as sterol glycosyltransferases (SGTs), commonly referred to as UGTs, leading to the production of steryl glycosides (SGs). The ratio of SGs and nonglyco-conjugated SAs are different in different plant species, however, their biosynthesis in the cell is controlled by different environmental factors. The aim of this review is to evaluate the current SGT enzyme research and the functional consequences of glycomodification of SAs on the physiology and plant development, which together are associated with the plant's primary processes. Pharmaceutical, industrial, and other potential uses of saponins have also been discussed and their use in therapeutics has been unveiled by in silico analysis. The field of biotransformation or conversion of nonglycosylated to glycosylated phytosterols by the activity of SGTs, making them soluble, available and more useful for humankind is the new field of interest towards drug therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Cationized Carbohydrate Gas-Phase Fragmentation Chemistry
NASA Astrophysics Data System (ADS)
Bythell, Benjamin J.; Abutokaikah, Maha T.; Wagoner, Ashley R.; Guan, Shanshan; Rabus, Jordan M.
2017-04-01
We investigate the fragmentation chemistry of cationized carbohydrates using a combination of tandem mass spectrometry, regioselective labeling, and computational methods. Our model system is D-lactose. Barriers to the fundamental glyosidic bond cleavage reactions, neutral loss pathways, and structurally informative cross-ring cleavages are investigated. The most energetically favorable conformations of cationized D-lactose were found to be similar. In agreement with the literature, larger group I cations result in structures with increased cation coordination number which require greater collision energy to dissociate. In contrast with earlier proposals, the B n -Y m fragmentation pathways of both protonated and sodium-cationized analytes proceed via protonation of the glycosidic oxygen with concerted glycosidic bond cleavage. Additionally, for the sodiated congeners our calculations support sodiated 1,6-anhydrogalactose B n ion structures, unlike the preceding literature. This affects the subsequent propensity of formation and prediction of B n /Y m branching ratio. The nature of the anomeric center (α/β) affects the relative energies of these processes, but not the overall ranking. Low-energy cross-ring cleavages are observed for the metal-cationized analytes with a retro-aldol mechanism producing the 0,2 A 2 ion from the sodiated forms . Theory and experiment support the importance of consecutive fragmentation processes, particularly for the protonated congeners at higher collision energies.
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Dietary flavonoid aglycones and their glycosides: Which show better biological significance?
Xiao, Jianbo
2017-06-13
The dietary flavonoids, especially their glycosides, are the most vital phytochemicals in diets and are of great general interest due to their diverse bioactivity. The natural flavonoids almost all exist as their O-glycoside or C-glycoside forms in plants. In this review, we summarized the existing knowledge on the different biological benefits and pharmacokinetic behaviors between flavonoid aglycones and their glycosides. Due to various conclusions from different flavonoid types and health/disease conditions, it is very difficult to draw general or universally applicable comments regarding the impact of glycosylation on the biological benefits of flavonoids. It seems as though O-glycosylation generally reduces the bioactivity of these compounds - this has been observed for diverse properties including antioxidant activity, antidiabetes activity, anti-inflammation activity, antibacterial, antifungal activity, antitumor activity, anticoagulant activity, antiplatelet activity, antidegranulating activity, antitrypanosomal activity, influenza virus neuraminidase inhibition, aldehyde oxidase inhibition, immunomodulatory, and antitubercular activity. However, O-glycosylation can enhance certain types of biological benefits including anti-HIV activity, tyrosinase inhibition, antirotavirus activity, antistress activity, antiobesity activity, anticholinesterase potential, antiadipogenic activity, and antiallergic activity. However, there is a lack of data for most flavonoids, and their structures vary widely. There is also a profound lack of data on the impact of C-glycosylation on flavonoid biological benefits, although it has been demonstrated that in at least some cases C-glycosylation has positive effects on properties that may be useful in human healthcare such as antioxidant and antidiabetes activity. Furthermore, there is a lack of in vivo data that would make it possible to make broad generalizations concerning the influence of glycosylation on the benefits of flavonoids for human health. It is possible that the effects of glycosylation on flavonoid bioactivity in vitro may differ from that seen in vivo. With in vivo (oral) treatment, flavonoid glycosides showed similar or even higher antidiabetes, anti-inflammatory, antidegranulating, antistress, and antiallergic activity than their flavonoid aglycones. Flavonoid glycosides keep higher plasma levels and have a longer mean residence time than those of aglycones. We should pay more attention to in vivo benefits of flavonoid glycosides, especially C-glycosides.
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Plant Sterols: Diversity, Biosynthesis, and Physiological Functions.
Valitova, J N; Sulkarnayeva, A G; Minibayeva, F V
2016-08-01
Sterols, which are isoprenoid derivatives, are structural components of biological membranes. Special attention is now being given not only to their structure and function, but also to their regulatory roles in plants. Plant sterols have diverse composition; they exist as free sterols, sterol esters with higher fatty acids, sterol glycosides, and acylsterol glycosides, which are absent in animal cells. This diversity of types of phytosterols determines a wide spectrum of functions they play in plant life. Sterols are precursors of a group of plant hormones, the brassinosteroids, which regulate plant growth and development. Furthermore, sterols participate in transmembrane signal transduction by forming lipid microdomains. The predominant sterols in plants are β-sitosterol, campesterol, and stigmasterol. These sterols differ in the presence of a methyl or an ethyl group in the side chain at the 24th carbon atom and are named methylsterols or ethylsterols, respectively. The balance between 24-methylsterols and 24-ethylsterols is specific for individual plant species. The present review focuses on the key stages of plant sterol biosynthesis that determine the ratios between the different types of sterols, and the crosstalk between the sterol and sphingolipid pathways. The main enzymes involved in plant sterol biosynthesis are 3-hydroxy-3-methylglutaryl-CoA reductase, C24-sterol methyltransferase, and C22-sterol desaturase. These enzymes are responsible for maintaining the optimal balance between sterols. Regulation of the ratios between the different types of sterols and sterols/sphingolipids can be of crucial importance in the responses of plants to stresses.
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Santos Pimenta, Lúcia P; Schilthuizen, Menno; Verpoorte, Robert; Choi, Young Hae
2014-01-01
Prunus serotina is native to North America but has been invasively introduced in Europe since the seventeenth century. This plant contains cyanogenic glycosides that are believed to be related to its success as an invasive plant. For these compounds, chromatographic- or spectrometric-based (targeting on HCN hydrolysis) methods of analysis have been employed so far. However, the conventional methods require tedious preparation steps and a long measuring time. To develop a fast and simple method to quantify the cyanogenic glycosides, amygdalin and prunasin in dried Prunus serotina leaves without any pre-purification steps using (1) H-NMR spectroscopy. Extracts of Prunus serotina leaves using CH3 OH-d4 and KH2 PO4 buffer in D2 O (1:1) were quantitatively analysed for amygdalin and prunasin using (1) H-NMR spectroscopy. Different internal standards were evaluated for accuracy and stability. The purity of quantitated (1) H-NMR signals was evaluated using several two-dimensional NMR experiments. Trimethylsilylpropionic acid sodium salt-d4 proved most suitable as the internal standard for quantitative (1) H-NMR analysis. Two-dimensional J-resolved NMR was shown to be a useful tool to confirm the structures and to check for possible signal overlapping with the target signals for the quantitation. Twenty-two samples of P. serotina were subsequently quantitatively analysed for the cyanogenic glycosides prunasin and amygdalin. The NMR method offers a fast, high-throughput analysis of cyanogenic glycosides in dried leaves permitting simultaneous quantification and identification of prunasin and amygdalin in Prunus serotina. Copyright © 2013 John Wiley & Sons, Ltd.
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Diphenamid metabolism in pepper and an ozone effect. II. Herbicide metabolite characterization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hodgson, R.H.; Hoffer, B.L.
Metabolites of diphenamid (N,N-dimethyl-2,2-diphenyl-acetamide) were purified from extracts of pepper plants (Capsicum frutescens L. Early Calwonder) treated via nutrient solution with the herbicide or several of its analogs. The major metabolites were characterized. Diphenamid was metabolized partially via a previously unreported pathway to N,N-dimethyl-2-phenyl-2-((hydroxyphenyl)-..beta..-0-D-glucosyl) acetamide and its monomethyl analog, and to N-hydroxy-methyl glycosides previously reported in other species. Ozone fumigation stimulated the production of both types of glycoside-conjugates. Leaves of plants that had been treated with 30 ..mu..M diphenamid and fumigated with ozone for 146 to 149 h contained 304 and 560 nmoles per gram of fresh weight of themore » hydroxyphenyl and N-hydroxymethyl conjugates, respectively. 7 references, 1 figure, 3 tables.« less
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Eckey-Kaltenbach, H.; Ernst, D.; Heller, W.; Sandermann, H.
1994-01-01
Parsley (Petroselinum crispum L.) is known to respond to ultraviolet irradiation by the synthesis of flavone glycosides, whereas fungal or elicitor stress leads to the synthesis of furanocoumarin phytoalexins. We tested how these defensive pathways are affected by a single ozone treatment (200 nL L-1; 10 h). Assays were performed at the levels of transcripts, for enzyme activities, and for secondary products. The most rapid transcript accumulation was maximal at 3 h, whereas flavone glycosides and furanocoumarins were maximally induced at 12 and 24 h, respectively, after the start of ozone treatment. Ozone acted as a cross-inducer because the two distinct pathways were simultaneously induced. These results are consistent with the previously observed ozone induction of fungal and viral defense reactions in tobacco, spruce, and pine. PMID:12232062
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Engineering cyanogen synthesis and turnover in cassava (Manihot esculenta).
Siritunga, Dimuth; Sayre, Richard
2004-11-01
Cassava is the major root crop for a quarter billion subsistence farmers in sub-Saharan Africa. It is valued for its ability to grow in adverse environments and the food security it provides. Cassava contains potentially toxic levels of cyanogenic glycosides (linamarin) which protect the plant from herbivory and theft. The cyanogens, including linamarin and its deglycosylated product, acetone cyanohydrin, can be efficiently removed from the root by various processing procedures. Short-cuts in processing, which may occur during famines, can result in only partial removal of cyanogens. Residual cyanogens in cassava foods may cause neurological disorders or paralysis, particularly in nutritionally compromised individuals. To address this problem and to further understand the function of cyanogenic glycosides in cassava, we have generated transgenic cassava in which cyanogenic glycoside synthesis has been selectively inhibited in leaves and roots by antisense expression of CYP79D1/D2 gene fragments. The CYP79D1/D2 genes encode two highly similar cytochrome P450s that catalyze the first-dedicated step in cyanogenic glycoside synthesis. Transgenic plants in which the expression of these genes was selectively inhibited in leaves had substantially reduced (60- 94% reduction) linamarin leaf levels. Surprisingly, these plants also had a greater than a 99% reduction in root linamarin content. In contrast, transgenic plants in which the CYP79D1/D2 transcripts were reduced to non-detectable levels in roots had normal root linamarin levels. These results demonstrate that linamarin synthesized in leaves is transported to the roots and accounts for nearly all of the root linamarin content. Importantly, transgenic plants having reduced leaf and root linamarin content were unable to grow in the absence of reduced nitrogen (NH3) . Cassava roots have previously been demonstrated to have an active cyanide assimilation pathway leading to the synthesis of amino acids. We propose that cyanide derived from linamarin is a major source of reduced nitrogen for cassava root protein synthesis. Disruption of linamarin transport from leaves in CYP79D1/D2 anti-sense plants prevents the growth of cassava roots in the absence of an alternate source of reduced nitrogen. An alternative strategy for reducing cyanogen toxicity in cassava foods is to accelerate cyanogenesis and cyanide volatilization during food processing. To achieve this objective, we have expressed the leaf-specific enzyme hydroxynitrile lyase (HNL) in roots. HNL catalyzes the breakdown of acetone cyanohydrin to cyanide. Expression of HNL in roots accelerated cyanogenesis by more than three-fold substantially reducing the accumulation of acetone cyanohydrin during processing relative to wild-type roots.
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Preliminary Phytochemical Studies.
2016-01-01
Plants are the natural producers of medicinal agents like alkaloids, flavonoids, tannins, and phenolics. These phytocompounds alone or in combination act as a therapeutic agent in various disease complications. Various chemical reagents are used to determine the major phytochemicals present in plant parts. Protocols involved in screening of alkaloids, carbohydrates, glycosides, saponins, phytosterols, fixed oils, and fats are shown in this chapter.
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USDA-ARS?s Scientific Manuscript database
Inulins are polysaccharides that belong to an important class of carbohydrates known as fructans and are used by many plants as a means of storing energy. Inulins contain 20 to several thousand fructose units joined by ß-2,1 glycosidic bonds, typically with a terminal glucose unit. Plants with high ...
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Mahrwald, R
2015-09-21
The aggressive and strong development of organocatalysis provides several protocols for the convenient utilization of the carbonyl function of unprotected carbohydrates in C-C-bond formation processes. These amine-catalyzed mechanisms enable multiple cascade-protocols for the synthesis of a wide range of carbohydrate-derived compound classes. Several, only slightly different protocols, have been developed for the application of 1,3-dicarbonyl compounds in the stereoselective chain-elongation of unprotected carbohydrates and the synthesis of highly functionalized C-glycosides of defined configuration. In addition, C-glycosides can also be accessed by amine-catalyzed reactions with methyl ketones. By a one-pot cascade reaction of isocyanides with unprotected aldoses and amino acids access to defined configured glycopeptide mimetics is achieved. Depending on the reaction conditions different origins to control the installation of configuration during the bond-formation process were observed.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Reindl, W.; Deng, K.; Gladden, J.M.
2011-05-01
The enzymatic hydrolysis of long-chain polysaccharides is a crucial step in the conversion of biomass to lignocellulosic biofuels. The identification and characterization of optimal glycoside hydrolases is dependent on enzyme activity assays, however existing methods are limited in terms of compatibility with a broad range of reaction conditions, sample complexity, and especially multiplexity. The method we present is a multiplexed approach based on Nanostructure-Initiator Mass Spectrometry (NIMS) that allowed studying several glycolytic activities in parallel under diverse assay conditions. Although the substrate analogs carried a highly hydrophobic perfluorinated tag, assays could be performed in aqueous solutions due colloid formation ofmore » the substrate molecules. We first validated our method by analyzing known {beta}-glucosidase and {beta}-xylosidase activities in single and parallel assay setups, followed by the identification and characterization of yet unknown glycoside hydrolase activities in microbial communities.« less
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ISOLATION OF GLYCOSIDES FROM THE BARKS OF ILEX ROTUNDA BY HIGH-SPEED COUNTER-CURRENT CHROMATOGRAPHY.
Wang, Chun; Chao, Zhimao; Sun, Wen; Wu, Xiaoyi; Ito, Yoichiro
2014-04-01
Semi-preparative and preparative high-speed counter-current chromatography (HSCCC) were successfully used for isolation of glycosides from 50% ethanol extract of the dried barks of Ilex rotunda Thunb. (Aquifoliaceae) by using a two-phase solvent system composed of ethyl acetate-n-butanol-water (1:6:7, v/v/v). From 1.0 g of the extract, syringaresinol 4',4"-di-o-β-d-glucopyranoside ( I , 20.2 mg),, syringin ( II , 56.8 mg), sinapaldehyde glucoside ( III , 26.2 mg),, syringaresinol 4'-o-β-d-glucopyranoside ( IV , 20.4 mg), and pedunculoside ( V , 45.1 mg) were obtained by one run of TBE-1000A HSCCC instrument with 1000 mL of column volume. Their structures were identified by IR, MS, and 1 H and 13 C NMR studies. Glycoside I was isolated from this plant for the first time.
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ISOLATION OF GLYCOSIDES FROM THE BARKS OF ILEX ROTUNDA BY HIGH-SPEED COUNTER-CURRENT CHROMATOGRAPHY
Wang, Chun; Chao, Zhimao; Sun, Wen; Wu, Xiaoyi; Ito, Yoichiro
2013-01-01
Semi-preparative and preparative high-speed counter-current chromatography (HSCCC) were successfully used for isolation of glycosides from 50% ethanol extract of the dried barks of Ilex rotunda Thunb. (Aquifoliaceae) by using a two-phase solvent system composed of ethyl acetate-n-butanol-water (1:6:7, v/v/v). From 1.0 g of the extract, syringaresinol 4',4"-di-o-β-d-glucopyranoside (I, 20.2 mg),, syringin (II, 56.8 mg), sinapaldehyde glucoside (III, 26.2 mg),, syringaresinol 4'-o-β-d-glucopyranoside (IV, 20.4 mg), and pedunculoside (V, 45.1 mg) were obtained by one run of TBE-1000A HSCCC instrument with 1000 mL of column volume. Their structures were identified by IR, MS, and 1H and 13C NMR studies. Glycoside I was isolated from this plant for the first time. PMID:25132792
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New phenethyl alcohol glycosides from Stachys parviflora.
Ahmad, Viqar Uddin; Arshad, Saima; Bader, Sadia; Ahmed, Amir; Iqbal, Shazia; Tareen, Rasool Buksh
2006-01-01
Phytochemical investigations of the whole plant of Stachys parviflora (Lamiaceae) resulted in the isolation of two new phenethyl alcohol glycosides. The structures of the new compounds named parviflorosides A and B were established as 2-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl-(1 --> 2)-4-O-E-caffeoyl-beta-D-glucopyranoside (1) and 2-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl-(1 --> 2)-6-O-E-caffeoyl-beta-D-glucopyranoside (2), respectively. The structure elucidation of the new compounds was based primarily on 1D and 2D NMR analysis, including COSY, HMBC and HMQC correlations.
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Verticillosides A-M: Polyoxygenated pregnane glycosides from Asclepias verticillata L.
Araya, Juan J; Binns, Franklin; Kindscher, Kelly; Timmermann, Barbara N
2012-06-01
As part of our ongoing effort to explore the chemical diversity of plants of the United States Midwest region, the isolation and identification of 13 pregnane glycosides named verticillosides A-M from Asclepias verticillata L. are reported. The structures of these compounds were elucidated by various spectroscopic techniques, including 1D and 2D NMR, IR, UV, and HRMS. The cytotoxicity of the isolates was evaluated against paired breast cell lines Hs578T (cancer) and Hs578Bst (normal), however, no significant growth inhibition was observed. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Milani, Paula G; Formigoni, Maysa; Dacome, Antonio S; Benossi, Livia; Costa, Cecília E M DA; Costa, Silvio C DA
2017-01-01
The aim of this study was to determine the composition and antioxidant potential of leaves of a new variety of Stevia rebaudiana (Stevia UEM-13). Stevia leaves of UEM-13 contain rebaudioside A as the main glycoside, while most wild Stevia plants contain stevioside. Furthermore can be multiplied by seed, which reduces the cost of plant culture techniques as other clonal varieties are multiplied by buds, requiring sophisticated and expensive seedling production systems. Ethanol and methanol were used in the extraction to determine the bioactive compounds. The methanolic extract was fractionated sequentially with hexane, chloroform, ethyl acetate and isobutanol, and the highest concentration of phenolic compounds and flavonoids was obtained in the ethyl acetate fraction (524.20 mg galic acid equivalent/g; 380.62 µg quercetin equivalent/g). The glycoside content varied greatly among the fractions (0.5% - 65.3%). Higher antioxidant potential was found in the methanol extract and the ethyl acetate fraction with 93.5% and 97.32%, respectively. In addition to being an excellent source for obtaining of extracts rich in glycoside, this new variety can also be used as raw material for the production of extracts or fractions with a significant amount of antioxidant activity and potential to be used as additives in food.
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De Capite, Annette; Lancaster, Tyler; Puthoff, David
2016-01-01
Black cohosh (Actaea racemosa) serves as the host plant for the Appalachian azure butterfly, Celastrina neglectamajor. Overharvesting of Black cohosh for the dietary supplement industry may result in its extirpation, and may also cause the elimination of the dependent butterfly. One way to increase or maintain the number of host plants in forested environments would be to reduce the number harvested, for example by increasing the levels of the desired metabolites in Black cohosh rhizomes. The secondary metabolites actein and deoxyactein are triterpene glycosides and are among the compounds associated with the putative activity of Black cohosh extracts. Acetein and deoxyacetein are used to standardize Black cohosh supplements. To gain an understanding of mechanisms that may control actein and deoxyactein accumulation, Black cohosh rhizomes were treated with exogenous salicylic acid, jasmonic acid, or ethylene, or were mechanically wounded. Salicylic acid treatment significantly increased the levels of actein and deoxyactein in the rhizome of Black cohosh, suggesting that the synthesis of triterpene glycosides is controlled in part by salicylic acid. Using salicylic acid or related chemicals to increase the levels of actein and deoxyactein in rhizomes may help supply the supplement industry and, simultaneously, help conserve Black cohosh and species dependent upon it.
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Structual Effects of Cytidine 2^' Ribose Modifications as Determined by Irmpd Action Spectroscopy
NASA Astrophysics Data System (ADS)
Hamlow, Lucas; He, Chenchen; Fan, Lin; Wu, Ranran; Yang, Bo; Rodgers, M. T.; Berden, Giel; Oomens, J.
2015-06-01
Modified nucleosides, both naturally occurring and synthetic play an important role in understanding and manipulating RNA and DNA. Naturally occurring modified nucleosides are commonly found in functionally important regions of RNA and also affect antibiotic resistance or sensitivity. Synthetic modifications of nucleosides such as fluorinated and arabinosyl nucleosides have found uses as anti-virals and chemotherapy agents. Understanding the effect that modifications have on structure and glycosidic bond stability may lend insight into the functions of these modified nucleosides. Modifications such as the naturally occurring 2^'-O-methylation and the synthetic 2^'-fluorination are believed to help stabilize the nucleoside through the glycosidic bond stability and intramolecular hydrogen bonding. Changing the sugar from ribose to arabinose alters the stereochemistry at the 2^' position and thus shifts the 3D orientation of the 2^'-hydroxyl group, which also affects intramolecular hydrogen bonding and glycosidic bond stability. The structures of 2^'-deoxy-2^'-fluorocytidine, 2^'-O-methylcytidine and cytosine arabinoside are examined in the current work by measuring the infrared spectra in the IR fingerprint region using infrared multiple photon dissociation (IRMPD) action spectroscopy. The structures accessed in the experiments were determined via comparison of the measured IRMPD action spectra to the theoretical linear IR spectra determined by density functional theory and molecular modeling for the stable low-energy structures. Although glycosidic bond stability cannot be quantitatively determined from this data, complementary TCID studies will establish the effect of these modifications. Comparison of these modified nucleosides with their RNA and DNA analogues will help elucidate differences in their intrinsic chemistry.
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Pan, Huiqin; Yang, Wenzhi; Zhang, Yibei; Yang, Min; Feng, Ruihong; Wu, Wanying; Guo, Dean
2015-08-01
The exploration of new chemical entities from herbal medicines may provide candidates for the in silico screening of drug leads. However, this significant work is hindered by the presence of multiple classes of plant metabolites and many re-discovered structures. This study presents an integrated strategy that uses ultrahigh-performance liquid chromatography/linear ion-trap quadrupole/Orbitrap mass spectrometry (UHPLC/LTQ-Orbitrap-MS) coupled with in-house library data for the systematic characterization and discovery of new potentially bioactive molecules. Exploration of the indole alkaloids from Uncaria rhynchophylla (UR) is presented as a model study. Initially, the primary characterization of alkaloids was achieved using mass defect filtering and neutral loss filtering. Subsequently, phytochemical isolation obtained 14 alkaloid compounds as reference standards, including a new one identified as 16,17-dihydro-O-demethylhirsuteine by NMR analyses. The direct-infusion fragmentation behaviors of these isolated alkaloids were studied to provide diagnostic structural information facilitating the rapid differentiation and characterization of four different alkaloid subtypes. Ultimately, after combining the experimental results with a survey of an in-house library containing 129 alkaloids isolated from the Uncaria genus, a total of 92 alkaloids (60 free alkaloids and 32 alkaloid O-glycosides) were identified or tentatively characterized, 56 of which are potential new alkaloids for the Uncaria genus. Hydroxylation on ring A, broad variations in the C-15 side chain, new N-oxides, and numerous O-glycosides, represent the novel features of the newly discovered indole alkaloid structures. These results greatly expand our knowledge of UR chemistry and are useful for the computational screening of potentially bioactive molecules from indole alkaloids. Graphical Abstract A four-step integrated strategy for the systematic characterization and efficient discovery of new indole alkaloids from Uncaria rhynchophylla.
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Chen, Si; Li, Meihong; Zheng, Gongyu; Wang, Tingting; Lin, Jun; Wang, Shanshan; Wang, Xiaxia; Chao, Qianlin; Cao, Shixian; Yang, Zhenbiao; Yu, Xiaomin
2018-01-24
Wuyi Rock tea, well-recognized for rich flavor and long-lasting fragrance, is a premium subcategory of oolong tea mainly produced in Wuyi Mountain and nearby regions of China. The quality of tea is mainly determined by the chemical constituents in the tea leaves. However, this remains underexplored for Wuyi Rock tea cultivars. In this study, we investigated the leaf metabolite profiles of 14 major Wuyi Rock tea cultivars grown in the same producing region using UPLC-QTOF MS and UPLC-QqQ MS with data processing via principal component analysis and cluster analysis. Relative quantitation of 49 major metabolites including flavan-3-ols, proanthocyanidins, flavonol glycosides, flavone glycosides, flavonone glycosides, phenolic acid derivatives, hydrolysable tannins, alkaloids and amino acids revealed clear variations between tea cultivars. In particular, catechins, kaempferol and quercetin derivatives were key metabolites responsible for cultivar discrimination. Information on the varietal differences in the levels of bioactive/functional metabolites, such as methylated catechins, flavonol glycosides and theanine, offers valuable insights to further explore the nutritional values and sensory qualities of Wuyi Rock tea. It also provides potential markers for tea plant fingerprinting and cultivar identification.
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Ullah, Nazif; Haq, Ihsan-Ul; Mirza, Bushra
2015-05-01
This work examines the crude methanolic extracts of three medicinally important plants native to Pakistan for potent phytotoxic activities and important phytochemicals. These plants include Euphorbia wallichii, Bergenia ciliata and Phytolacca latbenia. The phytotoxic effects were checked at 10,000, 1000, and 100 µg/ml against two economically important standard target species, Triticum aestivum (monocot representative) and Brassica napus (dicot representative). The phytotoxicity effects on seed germination, seedling growth and seedling weight were checked. A simple, cost-effective in vitro phytotoxicity assay (that uses petri plates) was used to evaluate the allelopathic properties of crude extracts. At highest concentration, extracts from all the three plants showed phytotoxic activities such that P. latbenia > E. wallichii > B. ciliata. In seedling growth, root length was affected more than shoot length, whereas among the target species B. napus was found to be more sensitive towards extracts when compared with T. aestivum. Phytochemical analysis showed that P. latbenia is rich in saponins and terpenoids, while E. wallichii and B. ciliata are rich in tannins, terpenoids and cardiac glycoside. P. latbenia also carries a moderate amount of cardiac glycosides. © The Author(s) 2012.
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Gonzales, Gerard Bryan; Raes, Katleen; Coelus, Sofie; Struijs, Karin; Smagghe, Guy; Van Camp, John
2014-01-03
In this paper, a strategy for the detection and structural elucidation of flavonoid glycosides from a complex matrix in a single chromatographic run using U(H)PLC-ESI-IMS-HDMS/MS(E) is presented. This system operates using alternative low and high energy voltages that is able to perform the task of conventional MS/MS in a data-independent way without re-injection of the sample, which saves analytical time. Also, ion mobility separation (IMS) was employed as an additional separation technique for compounds that are co-eluting after U(H)PLC separation. First, the fragmentation of flavonoid standards were analyzed and criteria was set for structural elucidation of flavonoids in a plant extract. Based on retention times, UV spectra, exact mass, and MS fragment characteristics, such as abundances of daughter ions and the presence of radical ions ([Y0-H](-)), a total 19 flavonoid glycosides, of which 8 non-acylated and 11 acylated, were detected and structurally characterized in a cauliflower waste extract. Kaempferol and quercetin were the main aglycones detected while sinapic and ferulic acid were the main phenolic acids. C-glycosides were also found although their structure could not be elucidated. The proposed method can be used as a rapid screening test for flavonoid identification and for routine analysis of plant extracts, such as these derived from cauliflower waste. The study also confirms that agroindustrial wastes, such as cauliflower leaves, could be seen as a valuable source of different bioactive phenolic compounds. Copyright © 2013 Elsevier B.V. All rights reserved.
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The Chemistry and Pharmacology of Citrus Limonoids.
Gualdani, Roberta; Cavalluzzi, Maria Maddalena; Lentini, Giovanni; Habtemariam, Solomon
2016-11-13
Citrus limonoids (CLs) are a group of highly oxygenated terpenoid secondary metabolites found mostly in the seeds, fruits and peel tissues of citrus fruits such as lemons, limes, oranges, pumellos, grapefruits, bergamots, and mandarins. Represented by limonin, the aglycones and glycosides of CLs have shown to display numerous pharmacological activities including anticancer, antimicrobial, antioxidant, antidiabetic and insecticidal among others. In this review, the chemistry and pharmacology of CLs are systematically scrutinised through the use of medicinal chemistry tools and structure-activity relationship approach. Synthetic derivatives and other structurally-related limonoids from other sources are include in the analysis. With the focus on literature in the past decade, the chemical classification of CLs, their physico-chemical properties as drugs, their biosynthesis and enzymatic modifications, possible ways of enhancing their biological activities through structural modifications, their ligand efficiency metrics and systematic graphical radar plot analysis to assess their developability as drugs are among those discussed in detail.
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Saifi, Monica; Nasrullah, Nazima; Ahmad, Malik Mobeen; Ali, Athar; Khan, Jawaid A; Abdin, M Z
2015-09-01
miRNAs are emerging as potential regulators of the gene expression. Their proven promising role in regulating biosynthetic pathways related gene networks may hold the key to understand the genetic regulation of these pathways which may assist in selection and manipulation to get high performing plant genotypes with better secondary metabolites yields and increased biomass. miRNAs associated with genes of steviol glycosides biosynthetic pathway, however, have not been identified so far. In this study miRNAs targeting genes of steviol glycosides biosynthetic pathway were identified for the first time whose precursors were potentially generated from ESTs and nucleotide sequences of Stevia rebaudiana. Thereafter, stem-loop coupled real time PCR based expressions of these miRNAs in different tissues of Stevia rebaudiana were investigated and their relationship pattern was analysed with the expression levels of their target mRNAs as well as steviol glycoside contents. All the miRNAs investigated showed differential expressions in all the three tissues studied, viz. leaves, flowers and stems. Out of the eleven miRNAs validated, the expression levels of nine miRNAs (miR319a, miR319b, miR319c, miR319d, miR319e, miR319f, miR319h, miRstv_7, miRstv_9) were found to be inversely related, while expression levels of the two, i.e. miR319g and miRstv_11 on the contrary, showed direct relation with the expression levels of their target mRNAs and steviol glycoside contents in the leaves, flowers and stems. This study provides a platform for better understanding of the steviol glycosides biosynthetic pathway and these miRNAs can further be employed to manipulate the biosynthesis of these metabolites to enhance their contents and yield in S. rebaudiana. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
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Colombo, Renata; Lanças, Fernando M; Yariwake, Janete H
2006-01-20
A high-performance liquid chromatography (HPLC) method with photo-diode array (DAD) detection was developed to separate and quantify flavonoids in sugarcane leaves and bagasse (= the crushed sugarcane refuse from juice extraction), and in sugarcane juice. Sugarcane flavonoids consist of a complex mixture of aglycones and glycosides (including flavonolignan glycosides), and the HPLC-UV method herein proposed is suitable for their quantification as total flavonoids. This method was applied to analyze samples of cultivated sugarcane, commercial juice and transgenic sugarcane leaves. Sugarcane leaves proved a promising source of flavonoids: an average of 1.10 mg of total flavonoids/g plant material was found in fresh leaves. Moreover, the flavonoid content of sugarcane juice (0.6 mg/mL) is comparable to other food sources of flavonoids previously reported. Transgenic sugarcane leaves ("Bowman-Birk" and "Kunitz") were compared with non-modified ("control") plant samples using the proposed HPLC-UV method, which indicated that the content of total flavonoids in transgenic plants is different from that in non-modified sugarcane.
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The substances of plant origin that inhibit protein biosynthesis.
Gałasiński, W; Chlabicz, J; Paszkiewicz-Gadek, A; Marcinkiewicz, C; Gindzieński, A
1996-01-01
Some plants were used for a long time in folk medicine as sources of anti-tumour remedies. Their effects on protein biosynthesis in vitro have been examined and described. The separate features of the peptide elongation system, isolated from tumoural cells, have been demonstrated. Some elongation factors or ribosomes have been shown to be a target site for the inhibition of protein biosynthesis caused by the substances isolated from various sources. The glycoside and caffeic acid, isolated from Melissa officinalis leaves, inhibited protein biosynthesis by direct influence the elongation factor eEF-2. The activity of this factor was also inhibited by aloin and aloeemodin. Saponin glycoside and its aglycon, isolated from Verbascum thapsiforme flowers, as well as digoxin, emetine and cepheline directly inactivated ribosomes. "Chagi" fraction, isolated from Inonotus obliquus, is responsible for the inhibitory effect caused by the aqueous tannin--less extract from this fungus. The target site for quercetin has been found to be the subunit form EF-1 alpha. It may be supposed that, the plant inhibitors of protein biosynthesis could be utilized for searching specific antitumoural preparations.
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Flavone C-glycosides from Anthurium andraeanum
USDA-ARS?s Scientific Manuscript database
Anthurium andraeanum is a popular ornamental plant that produces modified leaf structures known as spathes that are brightly colored due to accumulation of anthocyanins. While anthocyanin pigments of the Anthurium genus have been investigated, their other flavonoid constituents have received little ...
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Elmasri, Wael A; Yang, Tianjiao; Tran, Phat; Hegazy, Mohamed-Elamir F; Hamood, Abdul N; Mechref, Yehia; Paré, Paul W
2015-01-23
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.
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USDA-ARS?s Scientific Manuscript database
A variety of saponin glycosides and aglycones from seven different plant families (Aquifoliaceae, Asparagaceae, Caryophyllaceae, Dioscoreaceae, Leguminosae, Rosaceae, Sapindaceae) were tested against the corn earworm, Helicoverpa zea, and the fall armyworm, Spodoptera frugiperda. The corn earworm fe...
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Senica, Mateja; Stampar, Franci; Veberic, Robert; Mikulic-Petkovsek, Maja
2017-06-01
Elderberry (Sambucus nigra L.) possesses high antioxidant activity and has been used to treat numerous medicinal disorders. In addition to their antioxidant properties, elderberry parts accumulate toxic cyanogenic glycosides (CGG). It has been proven that altitude influences the biosynthesis of many secondary metabolites. In the present study we investigated the change of phenolics and CGG in elder leaves, flowers, and berries induced by different altitudes and locations. The data indicate that the accumulation of CGG and phenolics is affected by the altitude of the growing site. An increase of anthocyanin content was recorded in elder berries collected at higher elevations in both locations. Fruit collected at the foothills of location 2 contained 3343 µg g -1 anthocyanins as opposed to fruit from the hilltop, which contained 7729 µg g -1 . Elder berries contained the lowest levels of harmful CGG compared to other analysed plant parts. However, more cyanogenic glycosides were always present in plant parts collected at the hilltop. Accordingly, berries accumulated 0.11 µg g -1 CGG at the foothills and 0.59 µg g -1 CGG at the hilltop. Elder berries and flowers collected at the foothill were characterised by the lowest levels of both beneficial (phenolics) and harmful compounds (CGG) and are suitable for moderate consumption. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
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The Biochemistry, Chemistry and Physiology of the Isoflavones in Soybeans and their Food Products
2010-01-01
Abstract In this review of the chemistry, absorption, metabolism, and mechanisms of action of plant isoflavones, emphasis is placed on the isoflavones in soy and the food products derived from them. Soybeans have been part of food history in Asia for several millennia but did not reach the Americas and Europe until the eighteenth century. In the twentieth century, there was a tremendous increase in the cultivation of soybeans in the United States and more recently in South America. Soy foods have entered the U.S. food supply in ever-increasing amounts both in the form of traditional products (soy milk, tofu) and in more subtle ways in dairy and bread/cake products. The isoflavones in non-fermented foods are for the most part in the form of glycoside conjugates. These undergo changes due to different processing procedures. Isoflavones and their metabolites are well absorbed and undergo an enterohepatic circulation. They are often termed phytoestrogens because they bind to the estrogen receptors although weakly compared to physiologic estrogens. This estrogenicity is not the only mechanism by which isoflavones may have bioactivity—they inhibit tyrosine kinases, have antioxidant activity, bind to and activate peroxisome proliferator regulators α and γ, inhibit enzymes in steroid biosynthesis, strongly influence natural killer cell function and the activation of specific T-cell subsets, and inhibit metastasis. These various properties may explain the much lower incidence of hormonally-dependent breast cancer in Asian populations compared to Americans and Europeans. PMID:20235891
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Characterization of Stevia leaves by LC-QTOF MS/MS analysis of polar and non-polar extracts.
Molina-Calle, M; Priego-Capote, F; Luque de Castro, M D
2017-03-15
Stevia is currently a well-known plant thanks to its sweeting power. Numerous studies that elucidate its composition were exclusively focused on determination of steviol and its glycosides. Untargeted analysis was applied to obtain a profile of main compounds present in extracts from Stevia (Stevia rebaudiana Bertoni) leaves using LC-MS in high resolution mode with a quadrupole-time of flight analyzer. Eighty-nine compounds were tentatively identified and classified into different families: flavonoids; quinic and caffeic acids and derivatives; diterpenoids (including steviol and glycosides); sesquiterpenoids; amino acids and derivatives; fatty amides and derivatives; fatty acids and derivatives; oligosaccharides; glycerolipids; purines; and retinoids. New steviol glycosides were tentatively identified and their possible structures proposed. Other compounds were tentatively identified in Stevia for the first time, such as fatty acid amides. These results reveal the wide range of compounds present in Stevia, which could be responsible for the nutraceutical effects ascribed to their leaves. Copyright © 2016 Elsevier Ltd. All rights reserved.
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López, Víctor; Pérez, Sergio; Vinuesa, Arturo; Zorzetto, Christian; Abian, Olga
2016-04-01
Steviol glycosides are currently being used as natural sweeteners by the food industry and Stevia rebaudiana has long been used as a sweet plant in South America for patients suffering from diabetes. In this study, a Stevia rebaudiana ethanolic extract (SREE) was prepared, analysed and tested for antioxidant activity in terms of free radical scavenging properties and antiproliferative effects in cervix (HeLa), pancreatic (MiaPaCa-2) and colonic (HCT116) cancer cells. The antiproliferative mechanism was confirmed by testing the effects on cyclin D1-CDK4. Bioassays were also performed for the diterpene glycoside stevioside. Our results demonstrate that the extract acts as an antioxidant being able to scavenge free radicals, but this activity was not due to stevioside. The extract also induced cell death in the three cell lines, being more active against cervix cancer cells (HeLa); however, the concentration of stevioside needed to produce antiproliferative effects was higher than the amount of steviol glycosides found in a lower dose of extract inducing cell death. In addition, the extract clearly inhibited CDK4 whereas stevioside did not, concluding that the antiproliferative activity of stevia may be due to inhibition of cyclin-dependent kinases performed by other compounds of the extract.
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Cantabella, Daniel; Piqueras, Abel; Acosta-Motos, José Ramón; Bernal-Vicente, Agustina; Hernández, José A; Díaz-Vivancos, Pedro
2017-06-01
In order to cope with challenges linked to climate change such as salinity, plants must develop a wide spectrum of physiological and molecular mechanisms to rapidly adapt. Stevia rebaudiana Bertoni plants are a case in point. According to our findings, salt stress has no significant effect on plant growth in these plants, which accumulate sodium (Na + ) in their roots, thus avoiding excessive Na + accumulation in leaves. Furthermore, salt stress (NaCl stress) increases the potassium (K + ), calcium (Ca 2+ ), chloride ion (Cl - ) and proline concentrations in Stevia leaves, which could contribute to osmotic adjustment. We also found that long-term NaCl stress does not produce changes in chlorophyll concentrations in Stevia leaves, reflecting a mechanism to protect the photosynthesis process. Interestingly, an increase in chlorophyll b (Chlb) content occured in the oldest plants studied. In addition, we found that NaCl induced reactive oxygen species (ROS) accumulation in Stevia leaves and that this accumulation was more evident in the presence of 5 g/L NaCl, the highest concentration used in the study. Nevertheless, Stevia plants are able to induce (16 d) or maintain (25 d) antioxidant enzymes to cope with NaCl-induced oxidative stress. Low salt levels did not affect steviolbioside and rebaudioside A contents. Our results suggest that Stevia plants induce tolerance mechanisms in order to minimize the deleterious effects of salt stress. We can thus conclude that saline waters can be used to grow Stevia plants and for Steviol glycosides (SGs) production. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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Effect of sucrose concentrations on Stevia rebaudiana Bertoni tissue culture and gene expression.
Ghorbani, T; Kahrizi, D; Saeidi, M; Arji, I
2017-08-30
Stevia rebaudiana (Bert.) Bertoni is known as sweet plant which it contains a high level of steviol glycosides in the leaves. This plant has been used from centuries ago as a sweetener for tea. One of the most important steviol glycosides is stevioside that is attractive for diabetic persons. Tissue culture is the only rapid process for the mass propagation of stevia. One of the most important factors in the medium is sucrose that is a necessary for plant growth. In the present study, we use nodal segments of the stem as explants in mediums with different sucrose concentration (50 mM, 100mM and 150mM). Several morphological traits were measured in a 28 day period. Results analysis showed a significant variation between treatments. The highest growth rate, rooting and leaf production was obtained in medium with 100mM sucrose. The correlation between measured traits was significant at the 0.01 level. To investigation of UGT74G1, UGT76G1, UGT85C2 and KS genes expression that are involved in the synthesis of SGs, RT- PCR was done with the housekeeping gene of as internal control. There were significant differences between all media. The results showed thatsucrose 100 mM containing media was more desirable than others for expression of UGT76G1 and UGT85C2 genes. Whereas, the best medium for expression of UGT74G1 was sucrose 150 mM and sucrose 50 mM for KS gene. Totally, it seems that sucrose at a concentration of 100 mMprovides the best condition for stevia growth and steviol glycosides production.
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Gleadow, Roslyn M; Evans, John R; McCaffery, Stephanie; Cavagnaro, Timothy R
2009-11-01
Global food security in a changing climate depends on both the nutritive value of staple crops as well as their yields. Here, we examined the direct effect of atmospheric CO(2) on cassava (Manihot esculenta Cranz., manioc), a staple for 750 million people worldwide. Cassava is poor in nutrients and contains high levels of cyanogenic glycosides that break down to release toxic hydrogen cyanide when damaged. We grew cassava at three concentrations of CO(2) (C(a): 360, 550 and 710 ppm) supplied together with nutrient solution containing either 1 mM or 12 mM nitrogen. We found that total plant biomass and tuber yield (number and mass) decreased linearly with increasing C(a). In the worst-case scenario, tuber mass was reduced by an order of magnitude in plants grown at 710 ppm compared with 360 ppm CO(2). Photosynthetic parameters were consistent with the whole plant biomass data. It is proposed that since cassava stomata are highly sensitive to other environmental variables, the decrease in assimilation observed here might, in part, be a direct effect of CO(2) on stomata. Total N (used here as a proxy for protein content) and cyanogenic glycoside concentrations of the tubers were not significantly different in the plants grown at elevated CO(2). By contrast, the concentration of cyanogenic glycosides in the edible leaves nearly doubled in the highest C(a). If leaves continue to be used as a protein supplement, they will need to be more thoroughly processed in the future. With increasing population density, declining soil fertility, expansion into marginal farmland, together with the predicted increase in extreme climatic events, reliance on robust crops such as cassava will increase. The responses to CO(2) shown here point to the possibility that there could be severe food shortages in the coming decades unless CO(2) emissions are dramatically reduced, or alternative cultivars or crops are developed.
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Yang, Da-Hai; Baldwin, Ian T; Wu, Jianqiang
2013-06-01
The brassinosteroid (BR) receptor, BR insensitive 1 (BRI1), plays a critical role in plant development, but whether BRI1-mediated BR signaling is involved in plant defense responses to herbivores was largely unknown. Here, we examined the function of BRI1 in the resistance of Nicotiana attenuata (Solanaceae) to its specialist insect herbivore Manduca sexta. Jasmonic acid (JA) and JA-isoleucine conjugate (JA-Ile) are important hormones that mediate resistance to herbivores and we found that after wounding or simulated herbivory NaBRI1 had little effect on JA levels, but was important for the induction of JA-Ile. Further experiments revealed that decreased JAR (the enzyme for JA-Ile production) activity and availability of Ile in NaBRI1-silenced plants were likely responsible for the low JA-Ile levels. Consistently, M. sexta larvae gained more weight on NaBRI1-silenced plants than on the control plants. Quantification of insect feeding-induced secondary metabolites revealed that silencing NaBRI1 resulted in decreased levels of carbon-rich defensive secondary metabolites (hydroxygeranyllinalool diterpene glycosides, chlorogenic acid, and rutin), but had little effect on the nitrogen-rich ones (nicotine and trypsin proteinase inhibitors). Thus, NaBRI1-mediated BR signaling is likely involved in plant defense responses to M. sexta, including maintaining JA-Ile levels and the accumulation of several carbon-rich defensive secondary metabolites. © 2013 Institute of Botany, Chinese Academy of Sciences.
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Zhao, Xiao-Hui; Han, Fa; Li, Yu-Lin; Yue, Hui-Lan
2013-02-01
Stilbene glycosides are the primary constituents of Rheum tanguticum Maxim. ex Balf., to which different bioactivities has been attributed, including: anti-HIV, anti-oxidant, anti-tumour, anti-malarial, and anti-allergy activity. However, effective methods for the isolation and purification of stilbene glycosides, such as trans-rhapontin, cis-rhapontin and trans-desoxyrhaponticin, from this herb are not currently available. To develop an efficient method for the preparative isolation and purification of three stilbene glycosides from Rheum tanguticum Maxim. ex Balf. via high-speed counter-current chromatography (HSCCC). A solvent system composed of chloroform:n-butanol:methanol:water (4:1:3:2, v/v/v/v) was developed for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. The flow rate was 1.8 mL/min. The apparatus was controlled at 800 rpm and 25 °C, and the effluent was monitored at 280 nm. Chemical constituents were analysed by high-performance liquid chromatography (HPLC), and their structures were identified by ¹H- and ¹³C-NMR. Under the optimised conditions, 25.5 mg trans-rhapontin, 16.0 mg cis-rhapontin and 20.5 mg trans-desoxyrhaponticin were separated from 80 mg crude sample; the isolates had purities of 99.6, 97.2 and 99.2%, respectively. A simple and efficient HSCCC method has been optimised for the preparative separation of stilbene glycosides from Rheum tanguticum Maxim. ex Balf. Copyright © 2012 John Wiley & Sons, Ltd.
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Nuengchamnong, Nitra; Sookying, Sontaya; Ingkaninan, Kornkanok
2016-09-10
Bacopa monnieri (L.) Wettst. (Scrophulariaceae) is an Ayurvedic medicinal plant used as a memory enhancer. Its major chemical constituents are Bacopa saponins consisting of jujubogenin and pseudojujubogenin glycosides. These two aglycones are isomers different at the positions of prenyl substitution i.e., at C-23 for jujubogenin and at C-22 for pseudojujubogenin. In this study, we demonstrate the rapid and comprehensive characterization of saponin glycosides in B. monnieri using liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometer (LC-ESI-QTOF-MS). This shows that ESI-QTOF-MS in positive-ion mode, jujubogenin and pseudojujubogenin glycosides could be discriminated by the peak abundance ratio of m/z 455 [Aglycone+H-H2O](+) to m/z of 473 [Aglycone+H](+). Furthermore, the sequence of sugar moieties can be observed. In a similar manner, the isomeric saponins; deoxyjujubogenin and deoxypseudojujubogenin glycosides can be distinguished using the m/z 437[Aglycone+H-H2O](+) and m/z 455[Aglycone+H](+) peak ratio. Use of the negative-ion mode with MS/MS fragmentation can provide information about the type of sugar linked to the aglycone i.e., at m/z 633 (aglycone+glucose) or at m/z 603 (aglycone+arabinose). With our method, 62 chemical constituents in B. monnieri including saponin glycosides, flavonoids, and alkaloids were identified. This is the first systematic study in structural characterization on isomeric saponins and other metabolites in B. monnieri using ESI-QTOF-MS. Copyright © 2016 Elsevier B.V. All rights reserved.
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Won, Yu-Mi; Seong, Zuh-Kyung; Kim, Jae-Lim; Kim, Hui-Seong; Song, Hyuk-Hwan; Kim, Doo-Young; Kim, Jung-Hee; Oh, Sei-Ryang; Cho, Hyun-Woo; Cho, Jung-Hee; Lee, Hyeong-Kyu
2015-08-01
Three new triterpene glycosides (Lonicerosides K, L and M) and 11 known compounds were isolated from the aerial parts of Weigela subsessilis. Among the known isolated compounds, loniceroside A, sweroside, kaempferol-3-O-glucopyranoside 6″-(3-hydroxy-3-methylglutarate), kaempferol-3-O-acetylglucoside and grandifloroside were reported for the first time in a Weigela genus plant. Their chemical structures were identified using extensive spectroscopic analysis including two-dimensional (2D)-NMR experiments, HR-ESI-QTOF-MS and comparison with reported data. Among these compounds, lonicerosides A and L had potent melanogenesis stimulatory activity in murine B16F0 melanoma cells. The structural relationship of active compounds was discussed.
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Levels of a terpenoid glycoside (blumenin) and cell wall-bound phenolics in some cereal mycorrhizas.
Maier, W; Peipp, H; Schmidt, J; Wray, V; Strack, D
1995-01-01
Four cereals, Hordeum vulgare (barley), Triticum aestivum (wheat), Secale cereal (rye), and Avena sativa (oat), were grown in a defined nutritional medium with and without the arbuscular mycorrhizal fungus Glomus intraradices. Levels of soluble and cell wall-bound secondary metabolites in the roots of mycorrhizal and nonmycorrhizal plants were determined by high-performance liquid chromatography during the first 6 to 8 weeks of plant development. Whereas there was no difference in the levels of the cell wall-bound hydroxycinnamic acids, 4-coumaric and ferulic acids, there was a fungus-induced change of the soluble secondary root metabolites. The most obvious effect observed in all four cereals was the induced accumulation of a terpenoid glycoside. This compound was isolated and identified by spectroscopic methods (nuclear magnetic resonance, mass spectrometry) to be a cyclohexenone derivative, i.e. blumenol C 9-O-(2'-O-beta-glucuronosyl)-beta-glucoside. The level of this compound was found to be directly correlated with the degree of root colonization. PMID:7480342
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Wang, Wei; Fu, Xi-Wen; Dai, Xin-Long; Hua, Fang; Chu, Gang-Xiu; Chu, Ming-Jie; Hu, Feng-Lin; Ling, Tie-Jun; Gao, Li-Ping; Xie, Zhong-Wen; Wan, Xiao-Chun; Bao, Guan-Hu
2017-12-15
Zijuan tea is a special cultivar of Yunnan broad-leaf tea (Camellia sinensis var. assamica) with purple buds, leaves, and stems. Phytochemical study on this tea led to the discovery of three hydroxycinnamoylated catechins (HCCs) (1-3), seven other catechins (4-10), three proanthocyanidins (11-13), five flavones and flavone glycosides (14-18), two alkaloids (19, 20), one steroid (21), and one phenylpropanoid glycoside (22). The isolation and structural elucidation of the caffeoylated catechin (1) by means of spectroscopic techniques were described. We also provide the first evidence that 1 is synthesized via a two-step pathway in tea plant. The three HCCs (1-3) were investigated on their bioactivity through molecular modeling simulation and biochemical experiments. Our results show that they bind acetylcholinesterase (AChE) tightly and have strong AChE inhibitory activity with IC 50 value at 2.49, 11.41, 62.26μM, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Perner, Henrike; Rohn, Sascha; Driemel, Gregor; Batt, Natalie; Schwarz, Dietmar; Kroh, Lothar W; George, Eckhard
2008-05-28
The aim of the present study was to test whether variations in the root environment affect the content of health-related organosulfur compounds, total phenolic compounds, and flavonol glycoside concentrations in onions. For this purpose, greenhouse-grown onions ( Allium cepa L.) were either inoculated with a commercial arbuscular mycorrhizal inoculum or a sterile inoculum and were provided with two NH(4)(+):NO(3)(-) ratios as a nitrogen source. Onion growth, arbuscular mycorrhizal colonization rate, sugars, and nutrient element concentrations were also quantified. The plant antioxidant activity and quercetin monoglucoside and organosulfur compound concentrations increased with dominant nitrate supply. Furthermore, mycorrhizal colonization increased the antioxidant activity and also concentrations of the major quercetin glucosides. The present study provides clear evidence that antioxidant activity, quercetin glycosides, and organosulfur compounds can be increased in sufficiently supplied onion plants by dominant nitrate supply or application of arbuscular mycorrhizal fungi. This was probably due to increased precursor production and induced defense mechanisms.
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Paganga, G; Miller, N; Rice-Evans, C A
1999-02-01
Analysis of the major flavone, flavonol, anthocyanidin and hydroxycinnamic acid constituents (and their glycosides) of onion, tomato, egg plant and apple has been undertaken and the antioxidant activities of the phenolic extracts determined. The major phenolic antioxidant components of egg plant are chlorogenic acid in the flesh and a delphinidin conjugate in the skin. In the case of apple, the major phenolic antioxidants detected are chlorogenic acid, procyanidins/catechin compounds, rutin and phloridzin. Quercetin glycosides are well-known to be the major phenolic components of onion. Assessment of the antioxidant activities of a serving of 100g fresh weight fruit, vegetable and comparison with previously reported findings for 150 ml beverage (500 ml portion in the case of beer), expressed in micromol Trolox equivalents show that the antioxidant activities of 1 glass (150 ml) red wine equivalent to 12 glasses white wine equivalent to 2 cups of tea equivalent to 4 apples equivalent to 5 portions of onion equivalent to 5.5 portions egg plant equivalent to 3.5 glasses of blackcurrant juice equivalent to 3.5 (500 ml) glasses of beer equivalent to 7 glasses of orange juice equivalent to 20 glasses of apple juice (long life).
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ent-Kaurane Glycosides from Tricalysia okelensis
USDA-ARS?s Scientific Manuscript database
Tricalysia is a genus of the plant family Rubiaceae, with approximately 50 species distributed in subtropical and tropical areas in Asia and Africa, some of these used as folk medicine.1,2) Extensive phytochemical studies on Tricalysia dubia led to the isolation of a number of structurally diverse d...
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Identification of the phenolic components of collard greens, kale, and Chinese broccoli
USDA-ARS?s Scientific Manuscript database
An LC-MS profiling method was used to comprehensively study the phenolic components of collard greens, kale, and Chinese broccoli. This study led to the identification of 45 flavonoids and 13 hydroxycinnamic acid derivatives. All three plant materials contained kaempferol glycosides and acylgentio...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Donohoe, Bryon S.; Wei, Hui; Mittal, Ashutosh
In planta expression of a thermophilic endoglucanase (AcCel5A) reduces recalcitrance by creating voids and other irregularities in cell walls of Arabidopsis thaliana that increase enzyme accessibility without negative impacts on plant growth or cell wall composition. Furthermore, our results suggest that cellulose β-1–4 linkages can be cut sparingly in the assembling wall and that these minimal changes, made at the proper time, have an impact on plant cell wall recalcitrance without negative effects on overall plant development.
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Donohoe, Bryon S.; Wei, Hui; Mittal, Ashutosh; ...
2017-06-29
In planta expression of a thermophilic endoglucanase (AcCel5A) reduces recalcitrance by creating voids and other irregularities in cell walls of Arabidopsis thaliana that increase enzyme accessibility without negative impacts on plant growth or cell wall composition. Furthermore, our results suggest that cellulose β-1–4 linkages can be cut sparingly in the assembling wall and that these minimal changes, made at the proper time, have an impact on plant cell wall recalcitrance without negative effects on overall plant development.
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Lignans and aromatic glycosides from Piper wallichii and their antithrombotic activities.
Shi, Yan-Ni; Shi, Yi-Ming; Yang, Lian; Li, Xing-Cong; Zhao, Jin-Hua; Qu, Yan; Zhu, Hong-Tao; Wang, Dong; Cheng, Rong-Rong; Yang, Chong-Ren; Xu, Min; Zhang, Ying-Jun
2015-03-13
Piper wallichii (Miq.) Hand.-Mazz. is a medicinal plant used widely for the treatment of rheumatoid arthritis, inflammatory diseases, cerebral infarction and angina in China. Previous study showed that lignans and neolignans from Piper spp. had potential inhibitory activities on platelet aggregation. In the present study, we investigated the chemical constituents of Piper wallichii and their antithrombotic activities, to support its traditional uses. The methanolic extract of the air-dried stems of Piper wallichii was separated and purified using various chromatographic methods, including semi-preparative HPLC. The chemical structures of the isolates were determined by detailed spectroscopic analysis, and acidic hydrolysis in case of the new glycoside 2. Determination of absolute configurations of the new compound 1 was facilitated by calculated electronic circular dichroism using time-dependent density-functional theory. All compounds were tested for their inhibitory effects on platelet aggregation induced by platelet activating factor (PAF) in rabbits׳ blood model, from which the active ones were further evaluated the in vivo antithrombotic activity in zebrafish model. A new neolignan, piperwalliol A (1), and four new aromatic glycosides, piperwalliosides A-D (2-5) were isolated from the stems of Piper wallichii, along with 25 known compounds, including 13 lignans, six aromatic glycosides, two phenylpropyl aldehydes, and four biphenyls. Five known compounds (6-10) showed in vitro antiplatelet aggregation activities. Among them, (-)-syringaresinol (6) was the most active compound with an IC50 value of 0.52 mM. It is noted that in zebrafish model, the known lignan 6 showed good in vivo antithrombotic effect with a value of 37% at a concentration of 30 μM, compared with the positive control aspirin with the inhibitory value of 74% at a concentration of 125μM. This study demonstrated that lignans, phenylpropanoid and biphenyl found in Piper wallichii may be responsible for antithrombotic effect of the titled plant. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
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Tu, Xijuan; Ma, Shuangqin; Gao, Zhaosheng; Wang, Jing; Huang, Shaokang; Chen, Wenbin
2017-11-01
Flavonoids are frequently found as glycosylated derivatives in plant materials. To determine contents of flavonoid aglycones in these matrices, procedures for the extraction and hydrolysis of flavonoid glycosides are required. The current sample preparation method is both labour and time consuming. Develop a modified matrix solid phase dispersion (MSPD) procedure as an alternative methodology for the one-step extraction and hydrolysis of flavonoid glycosides. HPLC-DAD was applied for demonstrating the one-step extraction and hydrolysis of flavonoids in rape bee pollen. The obtained contents of flavonoid aglycones (quercetin, kaempferol, isorhamnetin) were used for the optimisation and validation of the method. The extraction and hydrolysis were accomplished in one step. The procedure completes in 2 h with silica gel as dispersant, a 1:2 ratio of sample to dispersant, and 60% aqueous ethanol with 0.3 M hydrochloric acid as the extraction solution. The relative standard deviations (RSDs) of repeatability were less than 5%, and the recoveries at two fortified levels were between 88.3 and 104.8%. The proposed methodology is simple and highly efficient, with good repeatability and recovery. Compared with currently available methods, the present work has advantages of using less time and labour, higher extraction efficiency, and less consumption of the acid catalyst. This method may have applications for the one-step extraction and hydrolysis of bioactive compounds from plant materials. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
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Qiu, Jian; Sun, Shuquan; Luo, Shiqiao; Zhang, Jichuan; Xiao, Xianzhou; Zhang, Liqun; Wang, Feng; Liu, Shizhong
2014-04-01
This study developed a new purple coloured Taraxacum brevicorniculatum plant through genetic transformation using the Arabidopsis AtPAP1 gene, which overproduced anthocyanins in its vegetative tissues. Rubber-producing Taraxacum plants synthesise high-quality natural rubber (NR) in their roots and so are a promising alternative global source of this raw material. A major factor in its commercialization is the need for multipurpose exploitation of the whole plant. To add value to the aerial tissues, red/purple plants of the rubber-producing Taraxacum brevicorniculatum species were developed through heterologous expression of the production of anthocyanin pigment 1 (AtPAP1) transcription factor from Arabidopsis thaliana. The vegetative tissue of the transgenic plants showed an average of a 48-fold increase in total anthocyanin content over control levels, but with the exception of pigmentation, the transgenic plants were phenotypically comparable to controls and displayed similar growth vigor. Southern blot analysis confirmed that the AtPAP1 gene had been integrated into the genome of the high anthocyanin Taraxacum plants. The AtPAP1 expression levels were estimated by quantitative real-time PCR and were highly correlated with the levels of total anthocyanins in five independent transgenic lines. High levels of three cyanidin glycosides found in the purple plants were characterized by high performance liquid chromatography-mass spectrum analysis. The presence of NR was verified by NMR and infrared spectroscopy, and confirmed that NR biosynthesis had not been affected in the transgenic Taraxacum lines. In addition, other major phenylpropanoid products such as chlorogenic acid and quercetin glycosides were also enhanced in the transgenic Taraxacum. The red/purple transgenic Taraxacum lines described in this study would increase the future application of the species as a rubber-producing crop due to its additional health benefits.
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Salminen, Juha-Pekka; Roslin, Tomas; Karonen, Maarit; Sinkkonen, Jari; Pihlaja, Kalevi; Pulkkinen, Pertti
2004-09-01
Oaks have been one of the classic model systems in elucidating the role of polyphenols in plant-herbivore interactions. This study provides a comprehensive description of seasonal variation in the phenolic content of the English oak (Quercus robur). Seven different trees were followed over the full course of the growing season, and their foliage repeatedly sampled for gallic acid, 9 individual hydrolyzable tannins, and 14 flavonoid glycosides, as well as for total phenolics, total proanthocyanidins, carbon, and nitrogen. A rare dimeric ellagitannin, cocciferin D2, was detected for the first time in leaves of Q. robur, and relationships between the chemical structures of individual tannins were used to propose a biosynthetic pathway for its formation. Overall, hydrolyzable tannins were the dominant phenolic group in leaves of all ages. Nevertheless, young oak leaves were much richer in hydrolyzable tannins and flavonoid glycosides than old leaves, whereas the opposite pattern was observed for proanthocyanidins. However, when quantified as individual compounds, hydrolyzable tannins and flavonoid glycosides showed highly variable seasonal patterns. This large variation in temporal trends among compounds, and a generally weak correlation between the concentration of any individual compound and the total concentration of phenolics, as quantified by the Folin-Ciocalteau method, leads us to caution against the uncritical use of summary quantifications of composite phenolic fractions in ecological studies.
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Fu, Bo; Ji, Xiaoming; Zhao, Mingqin; He, Fan; Wang, Xiaoli; Wang, Yiding; Liu, Pengfei; Niu, Lu
2016-09-01
Flavonoids are important secondary metabolites in plants regulated by the environment. To analyze the effect of light quality on the accumulation of flavonoids, we performed a rapid analysis of flavonoids in extracts of tobacco leaves using UHPLC-QTOF. A total of 12 flavonoids were detected and identified in tobacco leaves, which were classified into flavonoid methyl derivatives and flavonoid glycoside derivatives according to the groups linked to the flavonoid core. Correlation analysis was further conducted to investigate the effect of different wavelengths of light on their accumulation. The content of flavonoid methyl derivatives was positively correlated with the proportions of far-red light (FR; 716-810nm) and near-infrared light (NIR; 810-2200nm) in the sunlight spectrum and negatively correlated with the proportion of ultraviolet (UV-A; 350-400nm) and the red/far-red ratio (R/FR). By contrast, the content of flavonoid glycoside derivatives was positively correlated with the proportion of UV-A and the R/FR, and negatively correlated with FR and NIR. The results indicated that light quality with higher proportions of FR and NIR increases the activity of flavonoid methyltransferases but suppresses the activity of flavonoid glycoside transferases. While a high proportion of UV-A and a high R/FR can increase flavonoid glycoside transferase activity but suppress flavonoid methyltransferase activity. Copyright © 2016 Elsevier B.V. All rights reserved.
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The impact of pollen consumption on honey bee digestive physiology and carbohydrate metabolism
USDA-ARS?s Scientific Manuscript database
Carbohydrate-active enzymes play an important role in the honey bee (Apis mellifera) due to its dietary specialization on plant-based nutrition. Secretory glycoside hydrolases (GHs) produced in worker head glands aid in the processing of floral nectar into honey and are expressed in accordance with ...
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Effect of Fermentation on Compositional Changes of Cinnamomum osmophloeum Kaneh Leaves
NASA Astrophysics Data System (ADS)
Kurniawati, AD; Huang, TC; Kusnadi, J.
2017-04-01
Cinnamomum osmophloeum Kaneh is known as “indigenous cinnamon” with the chemical constituents of its leave’s essential oil are similar to the famous C. cassia inner bark oil. Its oil has long been used as a medicinal plant. Fermentation is one of the processes in tea production, which could change the compound’s composition. This research aims to study the compositional changes of C. osmophloeum leaves during fermentation compared to unfermented leaves and commercial tea leaves. The main bioactive secondary metabolites in C. osmophloeum leaves extract are two flavonol glycosides. Both of this glycosides changed into aglycone during fermentation. By using HPLC and LC-MS analysis the major components and their derivative were identified. The retention time of kaempferol aglycone was 35.21 minute and the concentration showed increased from 0.46 to 46.8 µg. mL-1 after fermentation. There are 3 major groups lactic acid bacteria isolated from fermented C. osmophloeum Kaneh leaves, Bacillus coagulans, Lactobacillus plantarum, and Pediococcus pentosaceus, which it plays the key role during the compositional changes of glycosides into aglycone.
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Secondary metabolites in floral nectar reduce parasite infections in bumblebees.
Richardson, Leif L; Adler, Lynn S; Leonard, Anne S; Andicoechea, Jonathan; Regan, Karly H; Anthony, Winston E; Manson, Jessamyn S; Irwin, Rebecca E
2015-03-22
The synthesis of secondary metabolites is a hallmark of plant defence against herbivores. These compounds may be detrimental to consumers, but can also protect herbivores against parasites. Floral nectar commonly contains secondary metabolites, but little is known about the impacts of nectar chemistry on pollinators, including bees. We hypothesized that nectar secondary metabolites could reduce bee parasite infection. We inoculated individual bumblebees with Crithidia bombi, an intestinal parasite, and tested effects of eight naturally occurring nectar chemicals on parasite population growth. Secondary metabolites strongly reduced parasite load, with significant effects of alkaloids, terpenoids and iridoid glycosides ranging from 61 to 81%. Using microcolonies, we also investigated costs and benefits of consuming anabasine, the compound with the strongest effect on parasites, in infected and uninfected bees. Anabasine increased time to egg laying, and Crithidia reduced bee survival. However, anabasine consumption did not mitigate the negative effects of Crithidia, and Crithidia infection did not alter anabasine consumption. Our novel results highlight that although secondary metabolites may not rescue survival in infected bees, they may play a vital role in mediating Crithidia transmission within and between colonies by reducing Crithidia infection intensities. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
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Secondary metabolites in floral nectar reduce parasite infections in bumblebees
Richardson, Leif L.; Adler, Lynn S.; Leonard, Anne S.; Andicoechea, Jonathan; Regan, Karly H.; Anthony, Winston E.; Manson, Jessamyn S.; Irwin, Rebecca E.
2015-01-01
The synthesis of secondary metabolites is a hallmark of plant defence against herbivores. These compounds may be detrimental to consumers, but can also protect herbivores against parasites. Floral nectar commonly contains secondary metabolites, but little is known about the impacts of nectar chemistry on pollinators, including bees. We hypothesized that nectar secondary metabolites could reduce bee parasite infection. We inoculated individual bumblebees with Crithidia bombi, an intestinal parasite, and tested effects of eight naturally occurring nectar chemicals on parasite population growth. Secondary metabolites strongly reduced parasite load, with significant effects of alkaloids, terpenoids and iridoid glycosides ranging from 61 to 81%. Using microcolonies, we also investigated costs and benefits of consuming anabasine, the compound with the strongest effect on parasites, in infected and uninfected bees. Anabasine increased time to egg laying, and Crithidia reduced bee survival. However, anabasine consumption did not mitigate the negative effects of Crithidia, and Crithidia infection did not alter anabasine consumption. Our novel results highlight that although secondary metabolites may not rescue survival in infected bees, they may play a vital role in mediating Crithidia transmission within and between colonies by reducing Crithidia infection intensities. PMID:25694627
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Hiras, Jennifer; Wu, Yu-Wei; Deng, Kai
ABSTRACT Glycoside hydrolases (GHs) are key enzymes in the depolymerization of plant-derived cellulose, a process central to the global carbon cycle and the conversion of plant biomass to fuels and chemicals. A limited number of GH families hydrolyze crystalline cellulose, often by a processive mechanism along the cellulose chain. During cultivation of thermophilic cellulolytic microbial communities, substantial differences were observed in the crystalline cellulose saccharification activities of supernatants recovered from divergent lineages. Comparative community proteomics identified a set of cellulases from a population closely related to actinobacteriumThermobispora bisporathat were highly abundant in the most active consortium. Among the cellulases fromT. bispora,more » the abundance of a GH family 12 (GH12) protein correlated most closely with the changes in crystalline cellulose hydrolysis activity. This result was surprising since GH12 proteins have been predominantly characterized as enzymes active on soluble polysaccharide substrates. Heterologous expression and biochemical characterization of the suite ofT. bisporahydrolytic cellulases confirmed that the GH12 protein possessed the highest activity on multiple crystalline cellulose substrates and demonstrated that it hydrolyzes cellulose chains by a predominantly random mechanism. This work suggests that the role of GH12 proteins in crystalline cellulose hydrolysis by cellulolytic microbes should be reconsidered. IMPORTANCECellulose is the most abundant organic polymer on earth, and its enzymatic hydrolysis is a key reaction in the global carbon cycle and the conversion of plant biomass to biofuels. The glycoside hydrolases that depolymerize crystalline cellulose have been primarily characterized from isolates. In this study, we demonstrate that adapting microbial consortia from compost to grow on crystalline cellulose generated communities whose soluble enzymes exhibit differential abilities to hydrolyze crystalline cellulose. Comparative proteomics of these communities identified a protein of glycoside hydrolase family 12 (GH12), a family of proteins previously observed to primarily hydrolyze soluble substrates, as a candidate that accounted for some of the differences in hydrolytic activities. Heterologous expression confirmed that the GH12 protein identified by proteomics was active on crystalline cellulose and hydrolyzed cellulose by a random mechanism, in contrast to most cellulases that act on the crystalline polymer in a processive mechanism.« less
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Goodger, Jason Q D; Woodrow, Ian E
2011-12-01
The glycosylation of lipophilic small molecules produces many important plant secondary metabolites. The majority of these are O-glycosides with relatively fewer occurring as glucose esters of aromatic or aliphatic acids. In particular, monoterpene acid glucose esters have much lower structural diversity and distribution compared to monoterpene glycosides. Nevertheless, there have been over 20 monoterpene acid glucose esters described from trees in the genus Eucalyptus (Myrtaceae) in recent years, all based on oleuropeic acid, menthiafolic acid or both. Here we review all of the glucose esters containing these monoterpenoids identified in plants to date. Many of the compounds contain phenolic aglycones and all contain at least one α,β-unsaturated carbonyl, affording a number of important potential therapeutic reactivities such as anti-tumor promotion, carcinogenesis suppression, and anti-oxidant and anti-inflammatory activities. Additional properties such as cytotoxicity, bitterness, and repellency are suggestive of a role in plant defence, but we also discuss their localization to the exterior of foliar secretory cavity lumina, and suggest they may also protect secretory cells from toxic terpenes housed within these structures. Finally we discuss how the use of a recently developed protocol to isolate secretory cavities in a functional state could be used in conjunction with systems biology approaches to help characterize their biosynthesis and roles in plants. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Zhang, Qunfeng; Liu, Meiya; Ruan, Jianyun
2017-03-20
As the predominant secondary metabolic pathway in tea plants, flavonoid biosynthesis increases with increasing temperature and illumination. However, the concentration of most flavonoids decreases greatly in light-sensitive tea leaves when they are exposed to light, which further improves tea quality. To reveal the metabolism and potential functions of flavonoids in tea leaves, a natural light-sensitive tea mutant (Huangjinya) cultivated under different light conditions was subjected to metabolomics analysis. The results showed that chlorotic tea leaves accumulated large amounts of flavonoids with ortho-dihydroxylated B-rings (e.g., catechin gallate, quercetin and its glycosides etc.), whereas total flavonoids (e.g., myricetrin glycoside, epigallocatechin gallate etc.) were considerably reduced, suggesting that the flavonoid components generated from different metabolic branches played different roles in tea leaves. Furthermore, the intracellular localization of flavonoids and the expression pattern of genes involved in secondary metabolic pathways indicate a potential photoprotective function of dihydroxylated flavonoids in light-sensitive tea leaves. Our results suggest that reactive oxygen species (ROS) scavenging and the antioxidation effects of flavonoids help chlorotic tea plants survive under high light stress, providing new evidence to clarify the functional roles of flavonoids, which accumulate to high levels in tea plants. Moreover, flavonoids with ortho-dihydroxylated B-rings played a greater role in photo-protection to improve the acclimatization of tea plants.
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Hoogenboom, Jorin; Lutz, Martin; Zuilhof, Han; Wennekes, Tom
2016-10-07
Starting from a chiral furanone, the nitrone-olefin [3 + 2] cycloaddition can be used to obtain bicyclic isoxazolidines for which we report a set of reactions to selectively modify each functional position. These synthetically versatile bicyclic isoxazolidines allowed us to obtain complex glycomimetic building blocks, like iminosugars, via multicomponent chemistry. For example, a library of 20 pipecolic acid derivatives, a recurring motif in various prescription drugs, could be obtained via a one-pot Staudinger/aza-Wittig/Ugi three-component reaction of a bicyclic isoxazolidine-derived azido-hemiacetal. Notably, specific pipecolic acids in this library were obtained via hydrolysis of an unique tricyclic imidate side product of the Ugi reaction. The azido-hemiacetal was also converted into an aza-C-glycoside iminosugar via an unprecendented one-pot Staudinger/aza-Wittig/Mannich reaction.
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Chaouali, Nadia; Dorra, Amira; Khelifi, Fathia; Nouioui, Anouer; Masri, Wafa; Belwaer, Ines; Ghorbel, Hayet; Hedhili, Abderazzek
2013-01-01
Under normal environmental conditions, many plants synthesize cyanogenic glycosides, which are able to release hydrogen cyanide upon hydrolysis. Each year, there are frequent livestock and occasional human victims of cyanogenic plants consumption. The present work aims to determine the hydrocyanic acid content in different samples of cyanogenic plants, selected from the Tunisian flora, and in the almond syrup. In order to evaluate their toxicity and their impact on the consumer health in the short term as well as in the long term, using the ISO 2164-1975 NT standard, relating to the determination of cyanogenic heterosides in leguminous plants. PMID:24171123
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Chaouali, Nadia; Gana, Ines; Dorra, Amira; Khelifi, Fathia; Nouioui, Anouer; Masri, Wafa; Belwaer, Ines; Ghorbel, Hayet; Hedhili, Abderazzek
2013-01-01
Under normal environmental conditions, many plants synthesize cyanogenic glycosides, which are able to release hydrogen cyanide upon hydrolysis. Each year, there are frequent livestock and occasional human victims of cyanogenic plants consumption. The present work aims to determine the hydrocyanic acid content in different samples of cyanogenic plants, selected from the Tunisian flora, and in the almond syrup. In order to evaluate their toxicity and their impact on the consumer health in the short term as well as in the long term, using the ISO 2164-1975 NT standard, relating to the determination of cyanogenic heterosides in leguminous plants.
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O'Neill, Bridget F; Zangerl, Arthur R; Dermody, Orla; Bilgin, Damla D; Casteel, Clare L; Zavala, Jorge A; DeLucia, Evan H; Berenbaum, May R
2010-01-01
Atmospheric levels of carbon dioxide (CO2) have been increasing steadily over the last century. Plants grown under elevated CO2 conditions experience physiological changes, particularly in phytochemical content, that can influence their suitability as food for insects. Flavonoids are important plant defense compounds and antioxidants that can have a large effect on leaf palatability and herbivore longevity. In this study, flavonoid content was examined in foliage of soybean (Glycine max Linnaeus) grown under ambient and elevated levels of CO2 and subjected to damage by herbivores in three feeding guilds: leaf skeletonizer (Popillia japonica Newman), leaf chewer (Vanessa cardui Linnaeus), and phloem feeder (Aphis glycines Matsumura). Flavonoid content also was examined in foliage of soybean grown under ambient and elevated levels of O3 and subjected to damage by the leaf skeletonizer P. japonica. The presence of the isoflavones genistein and daidzein and the flavonols quercetin and kaempferol was confirmed in all plants examined, as were their glycosides. All compounds significantly increased in concentration as the growing season progressed. Concentrations of quercetin glycosides were higher in plants grown under elevated levels of CO2. The majority of compounds in foliage were induced in response to leaf skeletonization damage but remained unchanged in response to non-skeletonizing feeding or phloem-feeding. Most compounds increased in concentration in plants grown under elevated levels of O3. Insects feeding on G. max foliage growing under elevated levels of CO2 may derive additional antioxidant benefits from their host plants as a consequence of the change in ratios of flavonoid classes. This nutritional benefit could lead to increased herbivore longevity and increased damage to soybean (and perhaps other crop plants) in the future.
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Rehana, Dilaveez; Mahendiran, D; Kumar, R Senthil; Rahiman, A Kalilur
2017-05-01
Copper oxide (CuO) nanoparticles were synthesized by green chemistry approach using different plant extracts obtained from the leaves of Azadirachta indica, Hibiscus rosa-sinensis, Murraya koenigii, Moringa oleifera and Tamarindus indica. In order to compare their efficiency, the same copper oxide nanoparticles was also synthesized by chemical method. Phytochemical screening of the leaf extracts showed the presence of carbohydrates, flavonoids, glycosides, phenolic compounds, saponins, tannins, proteins and amino acids. FT IR spectra confirmed the possible biomolecules responsible for the formation of copper oxide nanoparticles. The surface plasmon resonance absorption band at 220-235nm in the UV-vis spectra also supports the formation of copper oxide nanoparticles. XRD patterns revealed the monoclinic phase of the synthesized copper oxide nanoparticles. The average size, shape and the crystalline nature of the nanoparticles were determined by SEM, TEM and SAED analysis. EDX analysis confirmed the presence of elements in the synthesized nanoparticles. The antioxidant activity was evaluated by three different free radical scavenging assays. The cytotoxicity of copper oxide nanoparticles was evaluated against four cancer cell lines such as human breast (MCF-7), cervical (HeLa), epithelioma (Hep-2) and lung (A549), and one normal human dermal fibroblast (NHDF) cell line. The morphological changes were evaluated using Hoechst 33258 staining assay. Copper oxide nanoparticles synthesized by green method exhibited high antioxidant and cytotoxicity than that synthesized by chemical method. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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Fan, Shi-Qi; Li, Sen; Liu, Jin-Ling; Yang, Jiao; Hu, Chao; Zhu, Jun-Ping; Xiao, Xiao-Qin; Liu, Wen-Long; He, Fu-Yuan
2017-01-01
The molecular connectivity index was adopted to explore the characteristics of supramolecular imprinting template of herbs distributed to liver meridian, in order to provide scientific basis for traditional Chinese medicines(TCMs) distributed to liver meridian. In this paper, with "12th five-year plan" national planning textbooks Science of Traditional Chinese Medicine and Chemistry of Traditional Chinese Medicine as the blueprint, literatures and TCMSP sub-databases in TCM pharmacology of northwest science and technology university of agriculture and forestry were retrieved to collect and summarize active constituents of TCM distributed to liver meridian, and calculate the molecular connectivity index. The average molecular connectivity index of ingredients distributed to liver meridian was 9.47, which was close to flavonoid glycosides' (9.17±2.11) and terpenes (9.30±3.62). Therefore, it is inferred that template molecule of liver meridian is similar to physicochemical property of flavonoid glycosides and terpenes, which could be best matched with imprinting template of liver meridian. Copyright© by the Chinese Pharmaceutical Association.
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Ruthes, Andrea Caroline; Smiderle, Fhernanda Ribeiro; Iacomini, Marcello
2015-03-06
D-Glucans from edible mushrooms present diversified chemical structures. The most common type consists of a backbone of β-D-glucose (1→3)-linked frequently branched at O-6 by β-D-glucose residues as side chains. However it is possible to distinguish α-, β- and mixed D-glucans. Further discrimination could be made on the basis of glycosidic bond position in a pyranoid ring, distribution of specific glycosidic bonds along the chain, branching and molecular weight. The present manuscript reviews the processes of extraction, purification and chemical characterization of D-glucans, such as NMR studies, methylation analysis, Smith degradation, and some other methodologies employed in carbohydrate chemistry characterization. In addition, these polysaccharides are important because they can provide many therapeutic benefits related to their biological activity in animals and humans, either immunostimulatory activity, inhibiting tumor growth, as well as exerting antinociceptive and anti-inflammatory action, among others, which are usually attached to their structure, molecular weight and degree of branching. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Qi, Lu-Ming; Zuo, Zhi-Tian
2017-01-01
Gentiana rigescens Franch (Gentianaceae) is a famous medicinal plant for treatments of rheumatism, convulsion, and jaundice. Comprehensive investigation of different parts and cultivation years of this plant has not yet been conducted. This study presents the quantitative and qualitative characterization of iridoid glycosides from G. rigescens performed by HPLC and FTIR spectroscopy techniques. The accumulations of loganic acid, swertiamarin, gentiopicroside, and sweroside were determined. Results indicated that their content and distribution in different parts and cultivation years exhibit great variations. Gentiopicroside was identified as the most abundant compound among iridoid glycosides and its highest level was observed in the root of 2-year-old plant. With respect to qualitative variation of metabolic profile, the 1800–800 cm−1 band of FTIR spectra successfully discriminated different parts and cultivation years with the aid of PLS-DA. In addition, combined with PLSR, the feasibility of FTIR spectroscopy for determination of gentiopicroside was investigated by selecting characteristic wavelengths (1800–800 cm−1), which presented a good performance with a residual predictive deviation (RPD) of 3.646. Our results suggested that HPLC and FTIR techniques can complement each other and could be simultaneously applied for comparing and analyzing different parts and cultivation years of G. rigescens. PMID:28656121
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USDA-ARS?s Scientific Manuscript database
O-Glycosides of the cytokinin zeatin are found in many plant tissues. They provide protection against degradative enzymes and may serve as cytokinin reserves. Two zeatin glycosyltransferase (GT) genes, an O-glucosyltransferase (ZOG1) from Phaseolus lunatus and an O-xylosyltransferase (ZOX1) from P. ...
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Chemical structures of constituents from the whole plant of Bacopa monniera.
Ohta, Tomoe; Nakamura, Seikou; Nakashima, Souichi; Oda, Yoshimi; Matsumoto, Takahiro; Fukaya, Masashi; Yano, Mamiko; Yoshikawa, Masayuki; Matsuda, Hisashi
2016-07-01
Two new dammarane-type triterpene oligoglycosides, bacomosaponins A and B, and three new phenylethanoid glycosides, bacomosides A, B1, and B2, were isolated from the whole plant of Bacopa monniera Wettst. The chemical structures of the new constituents were characterized on the basis of chemical and physicochemical evidence. In the present study, bacomosaponins A and B with acyl groups were obtained from the whole plant of B. monniera. This is the first report of acylated dammarane-type triterpene oligoglycosides isolated from B. monniera. In addition, dammarane-type triterpene saponins significantly inhibited the aggregation of 42-mer amyloid β-protein.
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Marques, Rita; Sousa, Micaela M; Oliveira, Maria C; Melo, Maria J
2009-02-27
The natural dyes, and dye sources, in two seventeenth century Arraiolos carpets from the National Museum of Machado de Castro were analysed by high-performance liquid chromatography with UV-vis diode array detection (HPLC-DAD) and HPLC-mass spectrometry (LC-MS). Weld (Reseda luteola L.), indigo and spurge flax (Daphne gnidium L.) were found to be the dye sources, in agreement with original dyeing recipes collected during the nineteenth century. In order to fully characterize the plant sources, LC-MS conditions were optimized with plant extracts and the chromatographic separation and mass detection were enhanced. Extraction of the dyes, in the Arraiolos carpet samples, was performed using mild conditions that avoid glycoside decomposition. For the blues a dimethylformamide solution proved to be efficient for indigotin recovery. For all the other colours, an improved mild extraction method (with oxalic acid, methanol, acetone and water) was used, enabling to obtain the full dye source fingerprint, namely the flavonoid glycosides in the yellow dyes.
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Flavonoids modify root growth and modulate expression of SHORT-ROOT and HD-ZIP III.
Franco, Danilo Miralha; Silva, Eder Marques; Saldanha, Luiz Leonardo; Adachi, Sérgio Akira; Schley, Thayssa Rabelo; Rodrigues, Tatiane Maria; Dokkedal, Anne Ligia; Nogueira, Fabio Tebaldi Silveira; Rolim de Almeida, Luiz Fernando
2015-09-01
Flavonoids are a class of distinct compounds produced by plant secondary metabolism that inhibit or promote plant development and have a relationship with auxin transport. We showed that, in terms of root development, Copaifera langsdorffii leaf extracts has an inhibitory effect on most flavonoid components compared with the application of exogenous flavonoids (glycosides and aglycones). These compounds alter the pattern of expression of the SHORT-ROOT and HD-ZIP III transcription factor gene family and cause morpho-physiological alterations in sorghum roots. In addition, to examine the flavonoid auxin interaction in stress, we correlated the responses with the effects of exogenous application of auxin and an auxin transport inhibitor. The results show that exogenous flavonoids inhibit primary root growth and increase the development of lateral roots. Exogenous flavonoids also change the pattern of expression of specific genes associated with root tissue differentiation. These findings indicate that flavonoid glycosides can influence the polar transport of auxin, leading to stress responses that depend on auxin. Copyright © 2015 Elsevier GmbH. All rights reserved.
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Tian, Ye; Liimatainen, Jaana; Alanne, Aino-Liisa; Lindstedt, Anni; Liu, Pengzhan; Sinkkonen, Jari; Kallio, Heikki; Yang, Baoru
2017-04-01
Phenolic compounds of berries and leaves of thirteen various plant species were extracted with aqueous ethanol and analyzed with UPLC-DAD-ESI-MS, HPLC-DAD, and NMR. The total content of phenolics was consistently higher in leaves than in berries (25-7856 vs. 28-711mg/100g fresh weight). Sea buckthorn leaves were richest in phenolic compounds (7856mg/100g f.w.) with ellagitannins as the dominant compound class. Sea buckthorn berries contained mostly isorhamnetin glycosides, whereas quercetin glycosides were typically abundant in most samples investigated. Anthocyanins formed the dominating group of phenolics in most dark-colored berries but phenolic acid derivatives were equally abundant in saskatoon and chokeberry berries. Caffeoylquinic acids constituted 80% of the total phenolic content (1664mg/100g f.w.) in bilberry leaves. B-type procyanidins and caffeoylquinic acids were the major phenolic compounds in hawthorn and rowanberry, respectively. Use of leaves of some species with prunasin, tyramine and β-p-arbutin, may be limited in food applications. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Pons, T; Hernández, L; Batista, F R; Chinea, G
2000-11-01
The three-dimensional (3D) structure of fructan biosynthetic enzymes is still unknown. Here, we have explored folding similarities between reported microbial and plant enzymes that catalyze transfructosylation reactions. A sequence-structure compatibility search using TOPITS, SDP, 3D-PSSM, and SAM-T98 programs identified a beta-propeller fold with scores above the confidence threshold that indicate a structurally conserved catalytic domain in fructosyltransferases (FTFs) of diverse origin and substrate specificity. The predicted fold appeared related to that of neuraminidase and sialidase, of glycoside hydrolase families 33 and 34, respectively. The most reliable structural model was obtained using the crystal structure of neuraminidase (Protein Data Bank file: 5nn9) as template, and it is consistent with the location of previously identified functional residues of bacterial levansucrases (Batista et al., 1999; Song & Jacques, 1999). The sequence-sequence analysis presented here reinforces the recent inclusion of fungal and plant FTFs into glycoside hydrolase family 32, and suggests a modified sequence pattern H-x (2)-[PTV]-x (4)-[LIVMA]-[NSCAYG]-[DE]-P-[NDSC][GA]3 for this family.
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Pons, T.; Hernández, L.; Batista, F. R.; Chinea, G.
2000-01-01
The three-dimensional (3D) structure of fructan biosynthetic enzymes is still unknown. Here, we have explored folding similarities between reported microbial and plant enzymes that catalyze transfructosylation reactions. A sequence-structure compatibility search using TOPITS, SDP, 3D-PSSM, and SAM-T98 programs identified a beta-propeller fold with scores above the confidence threshold that indicate a structurally conserved catalytic domain in fructosyltransferases (FTFs) of diverse origin and substrate specificity. The predicted fold appeared related to that of neuraminidase and sialidase, of glycoside hydrolase families 33 and 34, respectively. The most reliable structural model was obtained using the crystal structure of neuraminidase (Protein Data Bank file: 5nn9) as template, and it is consistent with the location of previously identified functional residues of bacterial levansucrases (Batista et al., 1999; Song & Jacques, 1999). The sequence-sequence analysis presented here reinforces the recent inclusion of fungal and plant FTFs into glycoside hydrolase family 32, and suggests a modified sequence pattern H-x (2)-[PTV]-x (4)-[LIVMA]-[NSCAYG]-[DE]-P-[NDSC][GA]3 for this family. PMID:11305239
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Behar, Hila; Graham, Sean W; Brumer, Harry
2018-06-22
Carbohydrate-active enzymes (CAZymes) are central to the biosynthesis and modification of the plant cell wall. An ancient clade of bifunctional plant endo-glucanases (EG16 members) was recently revealed and proposed to represent a transitional group uniting plant xyloglucan endo-transglycosylase/hydrolase (XTH) gene products and bacterial mixed-linkage endo-glucanases in the phylogeny of Glycoside Hydrolase Family 16 (GH16). To gain broader insights into the distribution and frequency of EG16 and other GH16 members in plants, the Phytozome, Plaza, NCBI, and 1000 Plants databases were mined to build a comprehensive census among 1289 species spanning the broad phylogenetic diversity of multiple algae through recent plant lineages. EG16, newly identified EG16-2, and XTH members appeared first in the green algae. Extant EG16 members represent the early adoption of the β-jelly-roll protein scaffold from a bacterial or early-lineage eukaryotic GH16 gene, which is characterized by loop deletion and extension of the N-terminus (in EG16-2 members) or C-terminus (in XTH members). Maximum-likelihood phylogenetic analysis of EG16 and EG16-2 sequences are directly concordant with contemporary estimates of plant evolution. The lack of expansion of EG16 members into multi-gene families across green plants may point to a core metabolic role under tight control, in contrast to XTH genes that have undergone extensive duplications typical of cell-wall CAZymes. The present census will underpin future studies to elucidate the physiological role of EG16 members across plant species, and serve as roadmap for delineating the closely related EG16 and XTH gene products in bioinformatic analyses of emerging genomes and transcriptomes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
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Villalba, Juan J; Burritt, Elizabeth A; St Clair, Samuel B
2014-10-01
Aspen (Populus tremuloides Michx.) has evolved a chemical defense system comprised of phenolic glycosides (PG), which effectively deter insect herbivory. However, much less is known about the role of PG and the nutritional quality of the associated plant community on aspen browse susceptibility to mammalian herbivores. In three successive periods during the growing season, we conducted experiments with sheep by offering leaves from two aspen stands with different concentrations of PG (LOW, HIGH) or aspen leaves vs. leaves from a forb (Utah pea, Lathyrus pauciflorus) or a grass (smooth brome, Bromus inermis Leyss.) growing in an aspen understory. Intake of aspen (19 to 35 % PG) was low in all periods (1 to 6 g/Kg(0.75) in 2 hr) supporting the notion that aspen's defense system may contribute to its ecological success. However, lambs ate larger amounts of LOW than of HIGH suggesting that sheep could discriminate between aspen stands with different concentrations of PG, even when both stands were relatively well defended. Concentration of nutrients and chemical defenses in aspen leaves remained fairly stable across the growing season, and preference for aspen increased over the growing season. In contrast, preference for the forb and the grass decreased across the growing season in concert with a decline in the nutritional quality of these plants. The data suggest that nutritional context of aspen and associated forage species drove preference more than contrasts in defense chemistry of aspen. There may be periods of "susceptibility" of aspen use by mammalian herbivores, despite high concentrations of chemical defenses, which can potentially be targeted by management to reduce aspen herbivory.
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Gupta, Pratibha; Sharma, Satyawati; Saxena, Sanjay
2014-03-01
Steviol glycosides are natural non-caloric sweeteners which are extracted from the leaves of Stevia rebaudiana plant. Present study deals the effect of salts (NaCl and Na2CO3) on callus and suspension culture of Stevia plant for steviol glycoside (SGs) production. Yellow-green and compact calli obtained from in vitro raised Stevia leaves sub-cultured on MS medium supplemented with 2.0 mg l(-1) NAA and different concentrations of NaCl (0.05-0.20%) and Na2CO3 (0.0125-0.10%) for 2 weeks, and incubated at 24 ± 1 °C and 22.4 μmol m(-2) s(-1) light intensity provided by white fluorescent tubes for 16 h. Callus and suspension biomass cultured on salts showed less growth as well as browning of medium when compared with control. Quantification of SGs content in callus culture (collected on 15th day) and suspension cultures (collected at 10th and 15th days) treated with and without salts were analyzed by HPLC. It was found that abiotic stress induced by the salts increased the concentration of SGs significantly. In callus, the quantity of SGs got increased from 0.27 (control) to 1.43 and 1.57% with 0.10% NaCl, and 0.025% Na2CO3, respectively. However, in case of suspension culture, the same concentrations of NaCl and Na2CO3 enhanced the SGs content from 1.36 (control) to 2.61 and 5.14%, respectively, on the 10th day.
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Ruby; Santosh Kumar, R J; Vishwakarma, Rishi K; Singh, Somesh; Khan, Bashir M
2014-07-01
Health related benefits of isoflavones such as genistein are well known. Glycosylation of genistein yields different glycosides like genistein 7-O-glycoside (genistin) and genistein 4'-O-glycoside (sophoricoside). This is the first report on isolation, cloning and functional characterization of a glycosyltransferase specific for genistein 4'-O-glucoside from Bacopa monniera, an important Indian medicinal herb. The glycosyltransferase from B. monniera (UGT74W1) showed 49% identity at amino acid level with the glycosyltransferases from Lycium barbarum. The UGT74W1 sequence contained all the conserved motifs present in plant glycosyltransferases. UGT74W1 was cloned in pET-30b (+) expression vector and transformed into E. coli. The molecular mass of over expressed protein was found to be around 52 kDa. Functional characterization of the enzyme was performed using different substrates. Product analysis was done using LC-MS and HPLC, which confirmed its specificity for genistein 4'-O-glucoside. Immuno-localization studies of the UGT74W1 showed its localization in the vascular bundle. Spatio-temporal expression studies under normal and stressed conditions were also performed. The control B. monniera plant showed maximum expression of UGT74W1 in leaves followed by roots and stem. Salicylic acid treatment causes almost tenfold increase in UGT74W1 expression in roots, while leaves and stem showed decrease in expression. Since salicylic acid is generated at the time of injury or wound caused by pathogens, this increase in UGT74W1 expression under salicylic acid stress might point towards its role in defense mechanism.
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Application of LC-MS to the analysis of dyes in objects of historical interest
NASA Astrophysics Data System (ADS)
Zhang, Xian; Laursen, Richard
2009-07-01
High-performance liquid chromatography (HPLC) with photodiode array and mass spectrometric detection permits dyes extracted from objects of historical interest or from natural plant or animal dyestuffs to be characterized on the basis of three orthogonal properties: HPLC retention time, UV-visible spectrum and molecular mass. In the present study, we have focused primarily on yellow dyes, the bulk of which are flavonoid glycosides that would be almost impossible to characterize without mass spectrometric detection. Also critical for this analysis is a method for mild extraction of the dyes from objects (e.g., textiles) without hydrolyzing the glycosidic linkages. This was accomplished using 5% formic acid in methanol, rather than the more traditional 6 M HCl. Mass spectroscopy, besides providing the molecular mass of the dye molecule, sometimes yields additional structural data based on fragmentation patterns. In addition, coeluting compounds can often be detected using extracted ion chromatography. The utility of mass spectrometry is illustrated by the analysis of historical specimens of silk that had been dyed yellow with flavonoid glycosides from Sophora japonica (pagoda tree) and curcumins from Curcuma longa (turmeric). In addition, we have used these techniques to identify the dye type, and sometimes the specific dyestuff, in a variety of objects, including a yellow varnish from a 19th century Tibetan altar and a 3000-year-old wool mortuary textiles, from Xinjiang, China. We are using HPLC with diode array and mass spectrometric detection to create a library of analyzed dyestuffs (>200 so far; mostly plants) to serve as references for identification of dyes in objects of historical interest.
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Pandey, Madan Mohan; Khatoon, Sayyada; Rastogi, Subha; Rawat, Ajay Kumar Singh
2016-11-01
Tephrosia purpurea (Linn · ) Pers. is widely used in traditional medicine to treat liver disorders, febrile attacks, enlargement and obstruction of liver, spleen, and kidney. In the present study, investigations were carried out to determine the seasonal impact on the content of flavonoid glycosides and on antioxidant activities so as to identify the optimal time of harvesting. The plant materials were collected in different seasons during 2013-2014. Air-dried, powdered plant materials were extracted with 95% ethanol and ethanol: water (1:1) by ultrasound-assisted extraction process. Their chemical composition in terms of total polyphenol and flavonoid contents (TPCs and TFCs) was determined using modified colorimetric Folin-Ciocalteu method and aluminum chloride colorimetric assay respectively. To determine the in vitro antioxidant activity, diphenyl-picryl hydrazyl (DPPH) radical-scavenging assay and total antioxidant capacity by phosphomolybdate antioxidant assay were carried out. High-performance liquid chromatography (HPLC)/photo-diode array (PDA) analysis was used to quantify the flavonoid glycosides in the samples collected in different seasons. Correlation studies were also carried out between antioxidant activities and TPCs. The highest TPC and TFC were found to be in the 95% ethanolic extract of the August sample and the lowest in the 50% hydro-alcoholic extract of the plant sample collected in winter season. It was observed that in both the assays used to determine the antioxidant activity, the 95% ethanolic extracts in all the seasons showed a higher activity than their respective 50% hydro-alcoholic extracts with an increase in activity as we go from cold to hot to rainy seasons. Based on correlation analysis, DPPH radical-scavenging activities as well as the spectrophotometrically measured phosphomolybdenum complex were also strongly correlated with TPC of the extracts. The most abundant flavonoid glycoside was quercetin-3-O-rhamnoglucoside in all the seasons. The content of all flavonoids was observed highest in the 95% ethanolic extract of the plant collected in August (TP-3). The 50% hydro-alcoholic extract of the plant collected in December (TP-6) showed the lowest amount of flavonoids and antioxidant activity. The findings of this study confirmed that the metabolism and production of flavonoids in T. purpurea are vigorously affected by seasonal factors. Significant differences were observed in the TPC, TFC and flavonoid glycoside composition in the 95% ethanolic as well as 50% hydro-alcoholic extracts of T · purpurea collected in different seasons. Since the 95% ethanolic extract of the August sample (TP-3), which also happens to be its flowering season, exhibited the highest TPC, TFC and antioxidant activities in both DPPH and phosphomolybdate assays as well as contained the highest content of all flavonoids, it could be recommended as the optimal season of harvesting T · purpurea with respect to its pharmaceutically important constituents, i.e., flavonoids.
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Cardiac Glycoside Constituents of Streblus asper with Potential Antineoplastic Activity.
Ren, Yulin; Chen, Wei-Lun; Lantvit, Daniel D; Sass, Ellen J; Shriwas, Pratik; Ninh, Tran Ngoc; Chai, Hee-Byung; Zhang, Xiaoli; Soejarto, Djaja D; Chen, Xiaozhuo; Lucas, David M; Swanson, Steven M; Burdette, Joanna E; Kinghorn, A Douglas
2017-03-24
Three new (1-3) and two known (4 and 5) cytotoxic cardiac glycosides were isolated and characterized from a medicinal plant, Streblus asper Lour. (Moraceae), collected in Vietnam, with six new analogues and one known derivative (5a-g) synthesized from (+)-strebloside (5). A preliminary structure-activity relationship study indicated that the C-10 formyl and C-5 and C-14 hydroxy groups and C-3 sugar unit play important roles in the mediation of the cytotoxicity of (+)-strebloside (5) against HT-29 human colon cancer cells. When evaluated in NCr nu/nu mice implanted intraperitoneally with hollow fibers facilitated with either MDA-MB-231 human breast or OVCAR3 human ovarian cancer cells, (+)-strebloside (5) showed significant cell growth inhibitory activity in both cases, in the dose range 5-30 mg/kg.
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Phytopharmacology of Tribulus terrestris.
Shahid, M; Riaz, M; Talpur, M M A; Pirzada, T
2016-01-01
Tribulus terrestris is an annual herb which belongs to the Zygophyllaceae family. This plant has been used in traditional medicine for the treatment of various diseases for hundreds of decades. The main active phytoconstituents of this plant include flavonoids, alkaloids, saponins, lignin, amides, and glycosides. The plant parts have different pharmacological activities including aphrodisiac, antiinflammatory, antimicrobial and antioxidant potential. T. terrestris is most often used for infertility and loss of libido. It has potential application as immunomodulatory, hepatoprotective, hypolipidemic, anthelmintic and anticarcinogenic activities. The aim of the present article is to create a database for further investigation of the phytopharmacological properties of this plant to promote research. This study will definitely help to confirm its traditional use along with its value-added utility, eventually leading to higher revenues from the plant.
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Muhammad, Asim; Guerrero-Analco, Jose A; Martineau, Louis C; Musallam, Lina; Madiraju, Padma; Nachar, Abir; Saleem, Ammar; Haddad, Pierre S; Arnason, John T
2012-07-27
Through ethnobotanical surveys, the CIHR Team in Aboriginal Antidiabetic Medicines identified 17 boreal forest plants stemming from the pharmacopeia of the Cree First Nations of Eeyou Istchee (James Bay region of Northern Quebec) that were used traditionally against diabetes symptoms. The leaves of Sarracenia purpurea (pitcher plant), one of the identified Cree plants, exhibited marked antidiabetic activity in vitro by stimulating glucose uptake in C2C12 mouse muscle cells and by reducing glucose production in H4IIE rat liver cells. Fractionation guided by glucose uptake in C2C12 cells resulted in the isolation of 11 compounds from this plant extract, including a new phenolic glycoside, flavonoid glycosides, and iridoids. Compounds 6 (isorhamnetin-3-O-glucoside), 8 [kaempferol-3-O-(6″-caffeoylglucoside], and 11 (quercetin-3-O-galactoside) potentiated glucose uptake in vitro, which suggests they represent active principles of S. purpurea (EC(50) values of 18.5, 13.8, and 60.5 μM, respectively). This is the first report of potentiation of glucose uptake by compounds 6 and 8, while compound 11 (isolated from Vaccinium vitis) was previously shown to enhance glucose uptake. Treatment of H4IIE liver cells with the new compound 1, 6'-O-caffeoylgoodyeroside, decreased hepatic glucose production by reducing glucose-6-phosphatase enzymatic activity (IC(50) = 13.6 μM), which would contribute to lowering glycemia and to the antidiabetic potential of S. purpurea.
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Jin, Yu; Xiao, Yuan-sheng; Zhang, Fei-fang; Xue, Xing-ya; Xu, Qing; Liang, Xin-miao
2008-02-13
The traditional Chinese medicine (TCM) is a complex system, which always consists of numerous compounds with significant difference in the content and physical and chemical properties. In this paper, a screening method based on target molecular weights was developed to characterize the flavonoid glycosides in the flower of Carthamus tinctorius L. The screening tables of aglycone and glycan were designed, respectively, in order to select and combine freely. The multiple reaction monitoring (MRM) scan mode with higher sensitivity and selectivity was adopted in the screening, which benefit the characterization for the minor components. Seventy-seven flavonoid glycosides were screened out finally, and their structures were characterized by tandem mass spectrometric method in both positive and negative ion modes. The glycosylation mode, aglycone, sequence and/or the interglycosidic linkages of the glycan portion and glycosylation position were elucidated by the fragmentation rule in the MS. Numerous compounds screened out with this method showed the structure variety in secondary plant metabolites, and the purposeful screening systemically and subsequent structure characterization offered more information about the chemical constitutions of TCM.
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Dietary flavonoids: intake, health effects and bioavailability.
Hollman, P C; Katan, M B
1999-01-01
Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin. Over 4000 different flavonoids have been described. They may have beneficial health effects because of their antioxidant properties and their inhibitory role in various stages of tumour development in animal studies. An estimation of the total flavonoid intake is difficult, because only limited data on food contents are available. It is estimated that humans ingest a few hundreds of milligram per day. The average intake of the subclasses of flavonols and flavones in The Netherlands was 23 mg/day. The intake of flavonols and flavones was inversely associated with subsequent coronary heart disease in most but not all prospective epidemiological studies. A protective effect of flavonols on cancer was found in only one prospective study. Flavonoids present in foods were considered non-absorbable because they are bound to sugars as beta-glycosides. However, we found that human absorption of the quercetin glycosides from onions (52%) is far better than that of the pure aglycone (24%). Flavonol glycosides might contribute to the antioxidant defences of blood. Dietary flavonols and flavones probably do not explain the cancer-protective effect of vegetables and fruits; a protective effect against cardiovascular disease is not conclusive.
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Plants and Chemistry: A Teaching Course Based on the Chemistry of Substances of Plant Origin
NASA Astrophysics Data System (ADS)
Andreoli, Katia; Calascibetta, Franco; Campanella, Luigi; Favero, Gabriele; Occhionero, Francesca
2002-08-01
Over the past few years, we developed an idea about the teaching of chemistry by determining the links between theory and the real world. The principles, concepts, and experimental procedures of chemistry were illustrated through an original approach based on useful substances obtained from plants. The starting point was substances that have always been obtained from trees and vegetables. The approach was implemented during many refresher courses for secondary school teachers of chemistry. The courses were divided into sections, each called "Plants and ...", dedicated to colors, odors, tastes, medicines and drugs, fibers, soaps, and alcoholic beverages. Each section consisted of a theoretical lesson followed by a laboratory session.
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Jiwei Zhang; Gerald N. Presley; Kenneth E. Hammel; Jae-San Ryu; Jon R. Menke; Melania Figueroa; Dehong Hu; Galya Orr; Jonathan S. Schilling
2016-01-01
Wood-degrading brown rot fungi are essential recyclers of plant biomass in forest ecosystems. Their efficient cellulolytic systems, which have potential biotechnological applications, apparently depend on a combination of two mechanisms: lignocellulose oxidation (LOX) by reactive oxygen species (ROS) and polysaccharide hydrolysis by a limited set of glycoside...
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USDA-ARS?s Scientific Manuscript database
Maize ChitA chitinase is composed of a small, hevein-like domain attached to a carboxy-terminal chitinase domain. During fungal ear rot, the hevein-like domain is cleaved by secreted fungal proteases to produce truncated forms of ChitA. Here, we report a structural and biochemical characterization o...
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Traditional uses, phytochemistry, pharmacology and toxicology of the genus Cimicifuga: A review.
Guo, Yaqing; Yin, Tong; Wang, Xiaoming; Zhang, Fan; Pan, Guixiang; Lv, Hong; Wang, Xianrui; Owoicho Orgah, John; Zhu, Yan; Wu, Honghua
2017-09-14
Plants of the genus Cimicifuga have long been used as an ethnomedicine in China, Europe, and North America for its high medicinal value and health benefits. Their dried rhizomes are widely used for treating wind-heat headache, toothache, aphtha, sore throat, measles, spot poison, archoptosis, and uterine prolapse. In addition, it is used as a dietary supplement for preventing women menopausal symptoms and osteoporosis. This paper aims to provide up-to-date information on the genus Cimicifuga, including botanical characterization, medicinal resources, traditional medicinal uses, phytochemistry, quality control, pharmacological research as well as the toxicology. The possible structural-activity relationships and molecular mechanisms of the bioactive constituents are discussed in ways that contribute to the structural optimization and preclinical safety assessment for further drug design. The relevant information on Cimicifuga was collected from scientific databases (such as Google Scholar, PubMed, SciFinder Scholar, Science Direct, CNKI, Baidu Scholar, Web of Science, China Knowledge Resource Integrated Database), Chinese herbal classics, ethnobotanical books, PhD and MSc dissertations, Chinese Pharmacopoeia, published articles in peer-reviewed journals, local magazines, and unpublished materials. In addition, the Plant List (TPL, www.theplantlist.org) was also used to validate the scientific names and synonyms of this plant. The literature cited in this review dated from 1953 to 2017. The majority of chemical constituents of this plant include triterpenoid glycosides, phenylpropanoids, nitrogenous compounds, chromones, flavonoids and 4α-methyl steroid. Among them, the primary bioactive constituents are believed to be present in the triterpene glycoside fraction. To date, investigation of seven Cimicifuga spp. plants led to the identification of more than 457 compounds. Years of pharmacological research proved that the crude extracts and certain pure compounds obtained from Cimicifuga exhibited menopausal syndrome-treatment, anti-osteoporosis, antiviral, antitumor, antioxidant and antiangiogenic activities. On the other hand, Cimicifuga plant-induced toxicities of liver, cardiovascular, central and peripheral nervous systems have also been reported. Therefore, safety consideration should be placed into a high priority for herbal medicine Cimicifuga therapy in the early stages of development and clinical trials. This review presents information on botany, medicinal resources, and traditional medicinal history of some Cimicifuga plants. Modern pharmacology researchers have validated many traditional uses of Cimicifuga species. As the quality control and safety assessment of Cimicifuga plants is still incomplete, only a small part of the plant is permitted to be used as medicines. Expansion of medicinal resources in Cimicifuga is urgently needed to enable its full use. Currently research primarily focuses on the triterpenoid glycosides but there are many other types of compounds which may possess new biological activities however the systematic studies of these compounds are lacking. Extensive study is required on Cimicifuga plant before it can be fully used in clinics as a potent drug candidate. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
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Munafo, John P; Gianfagna, Thomas J
2011-02-09
The bulbs of the Easter lily ( Lilium longiflorum Thunb.) are regularly consumed in Asia as both food and medicine, and the beautiful white flowers are appreciated worldwide as an attractive ornamental. The Easter lily is a rich source of steroidal glycosides, a group of compounds that may be responsible for some of the traditional medicinal uses of lilies. Since the appearance of recent reports on the role steroidal glycosides in animal and human health, there is increasing interest in the concentration of these natural products in plant-derived foods. A LC-MS/MS method performed in multiple reaction monitoring (MRM) mode was used for the quantitative analysis of two steroidal glycoalkaloids and three furostanol saponins, in the different organs of L. longiflorum. The highest concentrations of the total five steroidal glycosides were 12.02 ± 0.36, 10.09 ± 0.23, and 9.36 ± 0.27 mg/g dry weight in flower buds, lower stems, and leaves, respectively. The highest concentrations of the two steroidal glycoalkaloids were 8.49 ± 0.3, 6.91 ± 0.22, and 5.83 ± 0.15 mg/g dry weight in flower buds, leaves, and bulbs, respectively. In contrast, the highest concentrations of the three furostanol saponins were 4.87 ± 0.13, 4.37 ± 0.07, and 3.53 ± 0.06 mg/g dry weight in lower stems, fleshy roots, and flower buds, respectively. The steroidal glycoalkaloids were detected in higher concentrations as compared to the furostanol saponins in all of the plant organs except the roots. The ratio of the steroidal glycoalkaloids to furostanol saponins was higher in the plant organs exposed to light and decreased in proportion from the aboveground organs to the underground organs. Additionally, histological staining of bulb scales revealed differential furostanol accumulation in the basal plate, bulb scale epidermal cells, and vascular bundles, with little or no staining in the mesophyll of the bulb scale. An understanding of the distribution of steroidal glycosides in the different organs of L. longiflorum is the first step in developing insight into the role these compounds play in plant biology and chemical ecology and aids in the development of extraction and purification methodologies for food, health, and industrial applications. In the present study, (22R,25R)-spirosol-5-en-3β-yl O-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranoside, (22R,25R)-spirosol-5-en-3β-yl O-α-l-rhamnopyranosyl-(1→2)-[6-O-acetyl-β-d-glucopyranosyl-(1→4)]-β-d-glucopyranoside, (25R)-26-O-(β-d-glucopyranosyl)furost-5-ene-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranoside, (25R)-26-O-(β-d-glucopyranosyl)furost-5-ene-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyl-(1→3)-β-d-glucopyranoside, and (25R)-26-O-(β-d-glucopyranosyl)furost-5-ene-3β,22α,26-triol 3-O-α-l-rhamnopyranosyl-(1→2)-α-l-xylopyranosyl-(1→3)-β-d-glucopyranoside were quantified in the different organs of L. longiflorum for the first time.
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Steviol glycosides in purified stevia leaf extract sharing the same metabolic fate.
Purkayastha, Sidd; Markosyan, Avetik; Prakash, Indra; Bhusari, Sachin; Pugh, George; Lynch, Barry; Roberts, Ashley
2016-06-01
The safety of steviol glycosides is based on data available on several individual steviol glycosides and on the terminal absorbed metabolite, steviol. Many more steviol glycosides have been identified, but are not yet included in regulatory assessments. Demonstration that these glycosides share the same metabolic fate would indicate applicability of the same regulatory paradigm. In vitro incubation assays with pooled human fecal homogenates, using rebaudiosides A, B, C, D, E, F and M, as well as steviolbioside and dulcoside A, at two concentrations over 24-48 h, were conducted to assess the metabolic fate of various steviol glycoside classes and to demonstrate that likely all steviol glycosides are metabolized to steviol. The data show that glycosidic side chains containing glucose, rhamnose, xylose, fructose and deoxy-glucose, including combinations of α(1-2), β-1, β(1-2), β(1-3), and β(1-6) linkages, were degraded to steviol mostly within 24 h. Given a common metabolite structure and a shared metabolic fate, safety data available for individual steviol glycosides can be used to support safety of purified steviol glycosides in general. Therefore, steviol glycosides specifications adopted by the regulatory authorities should include all steviol glycosides belonging to the five groups of steviol glycosides and a group acceptable daily intake established. Copyright © 2016 Elsevier Inc. All rights reserved.
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Triterpenoid saponins from Anemone flaccida induce apoptosis activity in HeLa cells.
Han, Lin-Tao; Li, Juan; Huang, Fang; Yu, Shang-Gong; Fang, Nian-Bai
2009-01-01
Five triterpenoid saponins were isolated from Anemone flaccida Fr. Schmidt. Their structures were identified as glycoside St-I4a (1), glycoside St-J (2), anhuienoside E (3), hederasaponin B (4), and flaccidoside II (5). Compounds 1-2 were isolated from Anemone family for the first time, and compounds 3-4 were isolated from this plant for the first time. The inhibitory effects of saponins on proliferation of HeLa cells were studied by MTT assay, the apoptosis-induction activity was observed by cell-cycle analysis and caspase-3 expression assay. The antitumor activities of the saponins were ranked in the following order: 5 > 3 > 4 > 1 > 2. The data presented here indicated that naturally occurring triterpenoid saponins can be regarded as excellent structures for the potential development of new anticancer agents.
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[Study on Megastigmane Glycosides and Lignan Constituents from Leaves of Psidium littorale].
Peng, Cai-ying; Liu, Jian-qun; Shu, Ji-cheng; Zhang, Rui
2014-12-01
To study the chemical constituents of the leaves of Psidium littorale. The constituents were isolated with silica gel column chromatography and the structures of these compounds were elucidated on the basis of spectral analysis. Four megastigmane glycosides and three lignans were isolated and their structures were identified as Bridelionoside B(1), Euodinoside E(2), (3S,5R,6R,7E,9S)-Megastignan-7-ene-3,5,6,9-tetrol 9-O-β-D-glucopyranoside (3), Bridelionoside C(4), (--)-Isolaricires-inol 3-α-O-β-D-glucopyranoside (5), (--)-5'-methoxy-Isolariciresinol 3-α-O-β-D-glucopyranoside (6) and dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside(7). Compounds 1-7 are isolated from this plant for the first time. The results have provided the scientific basis for further exploitation of Psidium littoratle.
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Yang, Yongheng; Huang, Suzhen; Han, Yulin; Yuan, Haiyan; Gu, Chunsun; Wang, Zhongwei
2015-01-01
Plant growth and secondary metabolism are commonly regulated by external cues such as light, temperature and water availability. In this study, the influences of low and high temperatures, dehydration, photoperiods, and different growing stages on the changes of steviol glycosides (SGs) contents and transcription levels of fifteen genes involved in SGs biosynthesis of Stevia rebaudiana Bertoni were examined using HPLC and RT-PCR. The observations showed that the transcript levels of all the fifteen genes were maximum under 25 °C treatment, and the transcription of SrDXS, SrDXR, SrMCT, SrCMK, SrMDS, SrHDS, SrHDR, SrIDI, SrGGDPS, SrCPPS1, SrUGT85C2 and SrUGT76G1 were restrained both in low temperature (15 °C) and high temperature (35 °C). Most genes in SGs biosynthesis pathway exhibited down-regulation in dehydration. To elucidate the effect of photoperiods, the plants were treated by different simulated photoperiods (8 L/16 D, 1 0L/14 D, 14 L/10 D and 16 L/8 D), but no significant transcription changes were observed. In the study of growing stages, there were evident changes of SGs contents, and the transcript levels of all the fifteen genes were minimal in fast growing period, and exhibited evident increase both in flower-bud appearing stage and flowering stage. The obtained results strongly suggest that the effect of environmental cues on steviol glycosides contents and transcription of corresponding biosynthetic genes in S. rebaudiana is significant. It is worth to study deeply. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
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Ichinose, Hitomi; Fujimoto, Zui; Honda, Mariko; Harazono, Koichi; Nishimoto, Yukifumi; Uzura, Atsuko; Kaneko, Satoshi
2009-09-11
Arabinogalactan proteins (AGPs) are a family of plant cell surface proteoglycans and are considered to be involved in plant growth and development. Because AGPs are very complex molecules, glycoside hydrolases capable of degrading AGPs are powerful tools for analyses of the AGPs. We previously reported such enzymes from Streptomyces avermitilis. Recently, a beta-l-arabinopyranosidase was purified from the culture supernatant of the bacterium, and its corresponding gene was identified. The primary structure of the protein revealed that the catalytic module was highly similar to that of glycoside hydrolase family 27 (GH27) alpha-d-galactosidases. The recombinant protein was successfully expressed as a secreted 64-kDa protein using a Streptomyces expression system. The specific activity toward p-nitrophenyl-beta-l-arabinopyranoside was 18 micromol of arabinose/min/mg, which was 67 times higher than that toward p- nitrophenyl-alpha-d-galactopyranoside. The enzyme could remove 0.1 and 45% l-arabinose from gum arabic or larch arabinogalactan, respectively. X-ray crystallographic analysis reveals that the protein had a GH27 catalytic domain, an antiparallel beta-domain containing Greek key motifs, another antiparallel beta-domain forming a jellyroll structure, and a carbohydrate-binding module family 13 domain. Comparison of the structure of this protein with that of alpha-d-galactosidase showed a single amino acid substitution (aspartic acid to glutamic acid) in the catalytic pocket of beta-l-arabinopyranosidase, and a space for the hydroxymethyl group on the C-5 carbon of d-galactose bound to alpha-galactosidase was changed in beta-l-arabinopyranosidase. Mutagenesis study revealed that the residue is critical for modulating the enzyme activity. This is the first report in which beta-l-arabinopyranosidase is classified as a new member of the GH27 family.
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Douché, Thibaut; San Clemente, Hélène; Burlat, Vincent; Roujol, David; Valot, Benoît; Zivy, Michel; Pont-Lezica, Rafael; Jamet, Elisabeth
2013-08-01
Polysaccharides make up about 75% of plant cell walls and can be broken down to produce sugar substrates (saccharification) from which a whole range of products can be obtained, including bioethanol. Cell walls also contain 5-10% of proteins, which could be used to tailor them for agroindustrial uses. Here we present cell wall proteomics data of Brachypodium distachyon, a model plant for temperate grasses. Leaves and culms were analyzed during active growth and at mature stage. Altogether, 559 proteins were identified by LC-MS/MS and bioinformatics, among which 314 have predicted signal peptides. Sixty-three proteins were shared by two organs at two developmental stages where they could play housekeeping functions. Differences were observed between organs and stages of development, especially at the level of glycoside hydrolases and oxidoreductases. Differences were also found between the known cell wall proteomes of B. distachyon, Oryza sativa, and the Arabidopsis thaliana dicot. Three glycoside hydrolases could be immunolocalized in cell walls using polyclonal antibodies against proteotypic peptides. Organ-specific expression consistent with proteomics results could be observed as well as cell-specific localization. Moreover, the high number of proteins of unknown function in B. distachyon cell wall proteomes opens new fields of research for monocot cell walls. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ito, Tasuku; Saikawa, Kyo; Kim, Seonah
2014-04-25
Graphical abstract: - Highlights: • HypBA1 β-L-arabinofuranosidase belongs to glycoside hydrolase family 127. • Crystal structure of HypBA1 was determined. • HypBA1 consists of a catalytic barrel and two additional β-sandwich domains. • The active site contains a Zn{sup 2+} coordinated by glutamate and three cysteines. • A possible reaction mechanism involving cysteine as the nucleophile is proposed. - Abstract: Enzymes acting on β-linked arabinofuranosides have been unknown until recently, in spite of wide distribution of β-L-arabinofuranosyl oligosaccharides in plant cells. Recently, a β-L-arabinofuranosidase from the glycoside hydrolase family 127 (HypBA1) was discovered in the newly characterized degradation system ofmore » hydroxyproline-linked β-L-arabinooligosaccharides in the bacterium Bifidobacterium longum. Here, we report the crystal structure of HypBA1 in the ligand-free and β-L-arabinofuranose complex forms. The structure of HypBA1 consists of a catalytic barrel domain and two additional β-sandwich domains, with one β-sandwich domain involved in the formation of a dimer. Interestingly, there is an unprecedented metal-binding motif with Zn{sup 2+} coordinated by glutamate and three cysteines in the active site. The glutamate residue is located far from the anomeric carbon of the β-L-arabinofuranose ligand, but one cysteine residue is appropriately located for nucleophilic attack for glycosidic bond cleavage. The residues around the active site are highly conserved among GH127 members. Based on biochemical experiments and quantum mechanical calculations, a possible reaction mechanism involving cysteine as the nucleophile is proposed.« less
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Hughes, Stephen R; Qureshi, Nasib; López-Núñez, Juan Carlos; Jones, Marjorie A; Jarodsky, Joshua M; Galindo-Leva, Luz Ángela; Lindquist, Mitchell R
2017-04-01
Inulins are polysaccharides that belong to an important class of carbohydrates known as fructans and are used by many plants as a means of storing energy. Inulins contain 20 to several thousand fructose units joined by β-2,1 glycosidic bonds, typically with a terminal glucose unit. Plants with high concentrations of inulin include: agave, asparagus, coffee, chicory, dahlia, dandelion, garlic, globe artichoke, Jerusalem artichoke, jicama, onion, wild yam, and yacón. To utilize inulin as its carbon and energy source directly, a microorganism requires an extracellular inulinase to hydrolyze the glycosidic bonds to release fermentable monosaccharides. Inulinase is produced by many microorganisms, including species of Aspergillus, Kluyveromyces, Penicillium, and Pseudomonas. We review various inulinase-producing microorganisms and inulin feedstocks with potential for industrial application as well as biotechnological efforts underway to develop sustainable practices for the disposal of residues from processing inulin-containing crops. A multi-stage biorefinery concept is proposed to convert cellulosic and inulin-containing waste produced at crop processing operations to valuable biofuels and bioproducts using Kluyveromyces marxianus, Yarrowia lipolytica, Rhodotorula glutinis, and Saccharomyces cerevisiae as well as thermochemical treatments.
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Ishisaki, Kana; Honda, Yuji; Taniguchi, Hajime; Hatano, Naoya; Hamada, Tatsuro
2012-03-01
A class IV chitinase belonging to the glycoside hydrolase 19 family from Nepenthes alata (NaCHIT1) was expressed in Escherichia coli. The enzyme exhibited weak activity toward polymeric substrates and significant activity toward (GlcNAc)(n) [β-1,4-linked oligosaccharide of GlcNAc with a polymerization degree of n (n = 4-6)]. The enzyme hydrolyzed the third and fourth glycosidic linkages from the non-reducing end of (GlcNAc)(6). The pH optimum of the enzymatic reaction was 5.5 at 37°C. The optimal temperature for activity was 60°C in 50 mM sodium acetate buffer (pH 5.5). The anomeric form of the products indicated that it was an inverting enzyme. The k(cat)/K(m) of the (GlcNAc)(n) hydrolysis increased with an increase in the degree of polymerization. Amino acid sequence alignment analysis between NaCHIT1 and a class IV chitinase from a Picea abies (Norway spruce) suggested that the deletion of four loops likely led the enzyme to optimize the (GlcNAc)(n) hydrolytic reaction rather than the hydrolysis of polymeric substrates.
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A new flavonol glycoside and other flavonoids from the aerial parts of Taverniera aegyptiaca.
Hassan, Ahmed R; Amer, Khadiga F; El-Toumy, Sayed A; Nielsen, John; Christensen, Søren Brøgger
2018-04-17
Isolation of flavonoids from the aerial parts of Taverniera aegyptiaca Bioss. (Fabaceae) led to identification of one new flavonol glycoside, isorhamnetin-3-O-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside (1), along with eleven compounds, which previously have not been isolated from this plant quercetin-3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)-β-d-galactopyranoside] (2), isorhamnetin-3-O-α-l-arabinopyranoside (3), quercetin-3-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (4), isorhamnetin-3-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (7), isorhamnetin 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)-β-d-galactopyranoside] (8), isorhamnetin 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside] (9), kaempferol 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)-β-d-galactopyranoside] (10), isorhamnetin (11), 4,4'-dihydroxy-2'-methoxychalcone (12), formononetin (13) and calycosin (15)] and some compounds already known from this plant [quercetin-3-O-robinobioside (5), isorhamnetin-3-O-robinobioside (6), afrormosin (14) and odoratin (16)].
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Flavonoid C- and O-glycosides from the Mongolian medicinal plant Dianthus versicolor Fisch.
Obmann, Astrid; Werner, Ingrid; Presser, Armin; Zehl, Martin; Swoboda, Zita; Purevsuren, Sodnomtseren; Narantuya, Samdan; Kletter, Christa; Glasl, Sabine
2011-09-27
Eighteen flavonoids were identified from an aqueous extract of the aerial parts of Dianthus versicolor, a plant used in traditional Mongolian medicine against liver diseases. The flavonoid C- and O-glycosides isoorientin-7-O-rutinoside, isoorientin-7-O-rhamnosyl-galactoside, isovitexin-7-O-rutinoside, isovitexin-7-O-rhamnosyl-galactoside, isoscoparin-7-O-rutinoside, isoscoparin-7-O-rhamnosyl-galactoside, isoscoparin-7-O-galactoside, and isoorientin-7-O-galactoside were isolated and structurally elucidated. Their structures were established on the basis of extensive spectroscopic techniques including LC-UV-DAD, LC-MS(n), LC-HRMS, 1D and 2D NMR spectroscopy, and by GC-MS analysis after hydrolysis. Flavonoids with such a high glycosylation pattern are rare within the genus Dianthus. Furthermore, isovitexin-7-O-glucoside (saponarin), isovitexin-2″-O-rhamnoside, apigenin-6-glucoside (isovitexin), luteolin-7-O-glucoside, apigenin-7-O-glucoside, as well as the aglycons luteolin, apigenin, chrysoeriol, diosmetin, and acacetin were identified by TLC and LC-DAD-MS(n) in comparison to reference substances or literature data. The NMR data of seven structures have not been reported in the literature to date. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Quercetin-3-O-glucuronide induces ABCA1 expression by LXRα activation in murine macrophages
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ohara, Kazuaki, E-mail: Kazuaki_Ohara@kirin.co.jp; Wakabayashi, Hideyuki; Taniguchi, Yoshimasa
Highlights: •The major circulating quercetin metabolite (Q3GA) activated LXRα. •Q3GA induced ABCA1 via LXRα activation in macrophages. •Nelumbo nucifera leaf extracts contained quercetin glycosides. •N. nucifera leaf extract feeding elevated HDLC in mice. -- Abstract: Reverse cholesterol transport (RCT) removes excess cholesterol from macrophages to prevent atherosclerosis. ATP-binding cassette, subfamily A, member 1 (ABCA1) is a crucial cholesterol transporter involved in RCT to produce high density lipoprotein-cholesterol (HDLC), and is transcriptionally regulated by liver X receptor alpha (LXRα), a nuclear receptor. Quercetin is a widely distributed flavonoid in edible plants which prevented atherosclerosis in an animal model. We found thatmore » quercetin-3-O-glucuronide (Q3GA), a major quercetin metabolite after absorption from the digestive tract, enhanced ABCA1 expression, in vitro, via LXRα in macrophages. In addition, leaf extracts of a traditional Asian edible plant, Nelumbo nucifera (NNE), which contained abundant amounts of quercetin glycosides, significantly elevated plasma HDLC in mice. We are the first to present experimental evidence that Q3GA induced ABCA1 in macrophages, and to provide an alternative explanation to previous studies on arteriosclerosis prevention by quercetin.« less
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Ammar, N M; El-Hawary, S S; Mohamed, D A; El-Halawany, A M; El-Anssary, A A; El-Kassem, L T Abou; Hussein, R A; Jaleel, G A Abdel; El-Dosoky, A H
2016-05-01
Luteolin-7-O-glycoside (LG), an abundant component in many edible plants, was found to be one of the major constituents of the aqueous methanol extract of Trifolium alexandrinum L. family Fabaceae, a fodder plant widely cultivated in Egypt. The estrogenic activity of LG concerning the effect on uterotrophy, lipid profile, weight gain and bone enhancement activity was determined in ovariectomized rat model at a dose of 5 mg/kg. Luteolin-7-O-glycoside showed significant estrogenic effect through the preservation of normal uterine weight and plasma estradiol level. It also significantly inhibited the bone turnover markers plasma bone-specific alkaline phosphatase, plasma osteocalsin, type I procollagen N-terminal, and C-telopeptide of type II collagen levels. It induced a significant improvement in plasma lipid profile. The effect of LG was comparable with estradiol with lower effect on uterine weight. Liver and kidney functions revealed a wide safety of LG at this dose level. The present study revealed that LG may be a promising hormone replacement therapy after being examined thoroughly on human. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
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Ma, Lifeng; Yi, Xiaoyun; Ruan, Jianyun
2014-01-01
To investigate the effect of light intensity and temperature on the biosynthesis and accumulation of quality-related metabolites, field grown tea plants were shaded by Black Net and Nano-insulating Film (with additional 2–4°C cooling effect) with un-shaded plants as a control. Young shoots were subjected to UPLC-Q-TOF MS followed by multivariate statistical analysis. Most flavonoid metabolites (mainly flavan-3-ols, flavonols and their glycosides) decreased significantly in the shading treatments, while the contents of chlorophyll, β-carotene, neoxanthin and free amino acids, caffeine, benzoic acid derivatives and phenylpropanoids increased. Comparison between two shading treatments indicated that the lower temperature under Nano shading decreased flavonols and their glycosides but increased accumulation of flavan-3-ols and proanthocyanidins. The comparison also showed a greater effect of temperature on galloylation of catechins than light intensity. Taken together, there might be competition for substrates between the up- and down-stream branches of the phenylpropanoid/flavonoid pathway, which was influenced by light intensity and temperature. PMID:25390340
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Zhang, Qunfeng; Shi, Yuanzhi; Ma, Lifeng; Yi, Xiaoyun; Ruan, Jianyun
2014-01-01
To investigate the effect of light intensity and temperature on the biosynthesis and accumulation of quality-related metabolites, field grown tea plants were shaded by Black Net and Nano-insulating Film (with additional 2-4°C cooling effect) with un-shaded plants as a control. Young shoots were subjected to UPLC-Q-TOF MS followed by multivariate statistical analysis. Most flavonoid metabolites (mainly flavan-3-ols, flavonols and their glycosides) decreased significantly in the shading treatments, while the contents of chlorophyll, β-carotene, neoxanthin and free amino acids, caffeine, benzoic acid derivatives and phenylpropanoids increased. Comparison between two shading treatments indicated that the lower temperature under Nano shading decreased flavonols and their glycosides but increased accumulation of flavan-3-ols and proanthocyanidins. The comparison also showed a greater effect of temperature on galloylation of catechins than light intensity. Taken together, there might be competition for substrates between the up- and down-stream branches of the phenylpropanoid/flavonoid pathway, which was influenced by light intensity and temperature.
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Lipoxygenase-inhibiting phenolic glycosides and monoterpene glycosides from Paeonia lactiflora.
Zou, Liang; Hu, Lin-Feng; Guo, Yi-Dong; Song, Yu; Fu, Qiang
2015-01-01
The EtOH extract of the roots of Paeonia lactiflora afforded a new phenolic glycoside paenoside A (1) and a new monoterpene glycoside paeonin D (2), and five known monoterpene glycosides. Their structures were elucidated on the basis of spectroscopic means and hydrolysis products. All compounds displayed inhibitory potential against enzyme lipoxygenase.
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Plant Chemistry and Local Adaptation of a Specialized Folivore
Laukkanen, Liisa; Leimu, Roosa; Muola, Anne; Lilley, Marianna; Salminen, Juha-Pekka; Mutikainen, Pia
2012-01-01
Local adaptation is central for creating and maintaining spatial variation in plant-herbivore interactions. Short-lived insect herbivores feeding on long-lived plants are likely to adapt to their local host plants, because of their short generation time, poor dispersal, and geographically varying selection due to variation in plant defences. In a reciprocal feeding trial, we investigated the impact of geographic variation in plant secondary chemistry of a long-lived plant, Vincetoxicum hirundinaria, on among-population variation in local adaptation of a specialist leaf-feeding herbivore, Abrostola asclepiadis. The occurrence and degree of local adaptation varied among populations. This variation correlated with qualitative and quantitative differences in plant chemistry among the plant populations. These findings provide insights into the mechanisms driving variation in local adaptation in this specialized plant-herbivore interaction. PMID:22666493
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Das, Sarita; Devaraj, S Niranjali
2006-09-01
For centuries, indigenous plants have been used against enteritis but their molecular targets and mode of action remain obscure. The present study was carried out to elucidate the protective and therapeutic role, if any, of glycosides from Hemidesmus indicus against S. typhimurium-induced pathogenesis. Studies were carried out in a human intestinal cell line (Int 407) and a murine macrophage cell line (P388D1) in order to evaluate its potency in local as well as systemic infections. The inhibitory role of the glycosides present in Hemidesmus indicus root extract (GHI) were tested by pre-coating the cells (both Int 407 and P388D1) with GHI prior to infection, and by neutralizing the wild-type bacteria with GHI before cell infection. In both cases, GHI protected the host cells from the cytotoxic effects of the wild S. typhimurium. This suggests that the biologically significant sugars (hexose, hexosamine, fucose and sialic acid etc) present in GHI might be mimicking host cell receptor saccharides and thereby blocking the bacterial ligands from binding to the host cells. Int 407 cells infected with wild-type bacteria had a diffused adherence pattern after 4 h incubation, but this typical character was not observed in cells infected with GHI-treated bacteria and the cells were normal in appearance at 4 h. After 18 h cells infected with wild-type bacteria were hypertrophoid with a disintegrated membrane and wrapped in a bacterial coat, whereas cells infected with treated bacteria had comparatively less morphological changes and few defective shrunken rods adhered locally. This suggests that the glycosides can change the adherence pattern of S. typhimurium from diffused to local. Treated bacteria had less adherence and invasion capability in Int 407 as well as P388D1 cells. The results show the decreased ability of adherence of GHI-treated S. typhimurium was due to a loss of surface hydrophobicity. A nonspecific binding between S. typhimurium and the glycosides was confirmed using ELISA. In summary, the glycosides of H. indicus root inhibited S. typhimurium induced pathogenesis nonspecifically, by reducing bacterial surface hydrophobicity and perhaps also by mimicking host cell receptors, thereby blocking its attachment to host cell and further pathological effects. Copyright (c) 2006 John Wiley & Sons, Ltd.
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Yao, Xin; Shang, Erxin; Zhou, Guisheng; Tang, Yuping; Guo, Sheng; Su, Shulan; Jin, Chun; Qian, Dawei; Qin, Yong; Duan, Jin-Ao
2012-01-01
The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years) are ignored and become obsolete after fruit harvest season (November). In this paper, we expand the tree age range (from one to 300 years) and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars. PMID:22949862
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Steviol Glycosides Modulate Glucose Transport in Different Cell Types
Rizzo, Benedetta; Zambonin, Laura; Leoncini, Emanuela; Vieceli Dalla Sega, Francesco; Prata, Cecilia; Fiorentini, Diana; Hrelia, Silvana
2013-01-01
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
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Kahrizi, D; Ghari, S M; Ghaheri, M; Fallah, F; Ghorbani, T; Beheshti Ale Agha, A; Kazemi, E; Ansarypour, Z
2017-08-15
Stevia rebaudiana is one of the most important biologically sourced and low-calorie sweeteners Bertoni that has a lot of steviol glycosides. Tissue culture is the best for propagation of stevia and micro nutrients can affect both morphological traits and steviol glycosides production. Therefore, the effect of different concentrations of KH2PO4on stevia growth factors and gene expression had been studied by tissue culture methods, RT-PCR and HPLC. According the results, bud numbers had increased significantly in MS + 0.034 mMKH2PO4 media and the highest measured length was seen in plants grown under MS + 0.034 mM KH2PO4 treatment. Also, the highest growth rate (1.396 mm/d) was observed in MS + 0.034 mMKH2PO4.The best concentration of KH2PO4 for expression of UGT74G1 was 0.00425mMand the best one for UGT76G1 expression was 0.017mM. Interestingly, the best media for both stevioside and rebaudioside A accumulation was 0.017mM KH2PO4containing media. There was positive correlation between the best media for gene expression and the best one for steviol glycosides production.
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Yang, Yong-Heng; Huang, Su-Zhen; Han, Yu-Lin; Yuan, Hai-Yan; Gu, Chun-Sun; Zhao, Yan-Hai
2014-07-01
Steviol glycosides, extracted from the leaves of Stevia rebaudiana (Bert) Bertoni, are calorie-free sugar substitute of natural origin with intensely sweet (Boileau et al., 2012). Stevioside and rebaudioside A are the two main kinds of the diterpenic glycosides. We analyzed the concentration of stevioside and rebaudioside A in Stevia leaves of about 500 samples (hybrid progenies) and discovered a mutation plant "Z05" with very low levels of rebaudioside A. Because UGT76G1, a uridinediphosphate-dependent glycosyltransferases, is responsible for the conversion from stevioside to rebaudioside A (Richman et al., 2005), so mutation identification was done by sequencing the candidate gene, UGT76G1. In this study molecular analysis of two strains revealed a heterozygotic nonsense mutation of c.389T > G (p.L121X) in UGT76G1. Meanwhile, we found some amino acid substitutions significant change the protein structure. And the difference of enzyme activity between two strains proved the lack of functionality of UGT76G1 of the mutation "Z05". So the nonsense mutation and amino acid substitution mutation resulted in the low levels of rebaudioside A. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
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Liu, Can; Dai, Longhai; Liu, Yueping; Rong, Long; Dou, Dequan; Sun, Yuanxia; Ma, Lanqing
2016-06-13
Colorectal cancer and throat cancer are the world's most prevalent neoplastic diseases, and a serious threat to human health. Plant triterpene glycosides have demonstrated antitumor activity. In this study, we investigated potential anticancer effects of mogroside IVe, a triterpenoid glycoside from monk fruit, using in vitro and in vivo models of colorectal and laryngeal cancer. The effects of mogroside IVe on the proliferation of colorectal cancer HT29 cells and throat cancer Hep-2 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the expression levels of p53, phosphorylated ERK1/2, and MMP-9 were analyzed by western blotting and immunohistochemistry. The results indicated that mogroside IVe inhibited, in a dose-dependent manner, the proliferation of HT29 and Hep-2 cells in culture and in xenografted mice, which was accompanied by the upregulation of tumor suppressor p53, and downregulation of matrix metallopeptidase 9 (MMP-9) and phosphorylated extracellular signal-regulated kinases (ERK)1/2. This study revealed the suppressive activity of mogroside IVe towards colorectal and throat cancers and identified the underlying mechanisms, suggesting that mogroside IVe may be potentially used as a biologically-active phytochemical supplement for treating colorectal and throat cancers.
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Health effects and bioavailability of dietary flavonols.
Hollman, P C; Katan, M B
1999-12-01
Flavonoids are polyphenolic compounds that are ubiquitously present in foods of plant origin. Flavonoids are categorised into flavonols, flavones, catechins, flavanones, anthocyanidins, and isoflavonoids. They may have beneficial health effects because of their antioxidant properties and their inhibitory role in various stages of tumour development in animal studies. It is estimated that the human intake of all flavonoids is a few hundreds of milligram per day. Flavonoids present in foods used to be considered non-absorbable because they are bound to sugars as beta-glycosides. However, we found that human absorption of the quercetin glycosides from onions (52%) is far better than that of the pure aglycone (24%). The sugar moiety is an important determinant of their absorption and bioavailability. Flavonol glycosides might contribute to the antioxidant defences of blood. The average intake of the flavonols quercetin, myricetin and kaempferol and the flavones luteolin and apigenin in the Netherlands was 23 mg/day. The intake of these flavonols and flavones was inversely associated with subsequent coronary heart disease in some but not all prospective epidemiological studies. A protective effect of flavonols on cancer was found in one prospective study; two others showed no association. Thus the epidemiological evidence does not yet allow a decision on the involvement of flavonols in the etiology of either cardiovascular diseases or cancer.
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Microscopic characterization of Scoparia dulcis Linn.(Scrophulariaceae)
Mishra, Manas Ranjan; Mishra, Ashutosh; Pradhan, Dusmanta Kumar; Behera, Rajani Kanta; Jha, Shivesh; Panda, Ashok Kumar; Choudhary, Punit Ram
2012-01-01
This manuscript covers a detailed pharmacognostic evaluation of Scoparia dulcis Linn. whole plant (Scrophulariaceae), including morphology, microscopy, physicochemical, and phytochemical screening. Microscopy of different plant part was done by performing transverse sections and longitudinal sections, which were identified by the different staining reagents and dyes. Physicochemical constants were done for whole plant; it includes ash value, extractive value and moisture content. Phytochemical screening was done for aqueous and methanolic extract in maceration and soxhletion, results revealed the presence of alkaloids, glycosides, carbohydrates, phenolic compound, flavonoids, saponins, proteins, and amino acids. These study includes parameters to establish the authenticity of S. dulcis and can possibly help to differentiate the drug from its other species. PMID:23929991
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Microscopic characterization of Scoparia dulcis Linn.(Scrophulariaceae).
Mishra, Manas Ranjan; Mishra, Ashutosh; Pradhan, Dusmanta Kumar; Behera, Rajani Kanta; Jha, Shivesh; Panda, Ashok Kumar; Choudhary, Punit Ram
2012-07-01
This manuscript covers a detailed pharmacognostic evaluation of Scoparia dulcis Linn. whole plant (Scrophulariaceae), including morphology, microscopy, physicochemical, and phytochemical screening. Microscopy of different plant part was done by performing transverse sections and longitudinal sections, which were identified by the different staining reagents and dyes. Physicochemical constants were done for whole plant; it includes ash value, extractive value and moisture content. Phytochemical screening was done for aqueous and methanolic extract in maceration and soxhletion, results revealed the presence of alkaloids, glycosides, carbohydrates, phenolic compound, flavonoids, saponins, proteins, and amino acids. These study includes parameters to establish the authenticity of S. dulcis and can possibly help to differentiate the drug from its other species.
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Plant litter chemistry and mycorrhizal roots promote a nitrogen feedback in a temperate forest.
Nina Wurzburger; Ronald L. Hendrick
2009-01-01
1. Relationships between mycorrhizal plants and soil nitrogen (N) have led to the speculation that the chemistry of plant litter and the saprotrophy of mycorrhizal symbionts can function together to...
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Measurement of food flavonoids by high-performance liquid chromatography: A review.
Merken, H M; Beecher, G R
2000-03-01
The flavonoids are plant polyphenols found frequently in fruits, vegetables, and grains. Divided into several subclasses, they include the anthocyanidins, pigments chiefly responsible for the red and blue colors in fruits, fruit juices, wines, and flowers; the catechins, concentrated in tea; the flavanones and flavanone glycosides, found in citrus and honey; and the flavones, flavonols, and flavonol glycosides, found in tea, fruits, vegetables, and honey. Known for their hydrogen-donating antioxidant activity as well as their ability to complex divalent transition metal cations, flavonoids are propitious to human health. Computer-controlled high-performance liquid chromatography (HPLC) has become the analytical method of choice. Many systems have been developed for the detection and quantification of flavonoids across one, two, or three subclasses. A summary of the various HPLC and sample preparation methods that have been employed to quantify individual flavonoids within a subclass or across several subclasses are tabulated in this review.
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Philippaert, Koenraad; Pironet, Andy; Mesuere, Margot; Sones, William; Vermeiren, Laura; Kerselaers, Sara; Pinto, Sílvia; Segal, Andrei; Antoine, Nancy; Gysemans, Conny; Laureys, Jos; Lemaire, Katleen; Gilon, Patrick; Cuypers, Eva; Tytgat, Jan; Mathieu, Chantal; Schuit, Frans; Rorsman, Patrik; Talavera, Karel; Voets, Thomas; Vennekens, Rudi
2017-01-01
Steviol glycosides (SGs), such as stevioside and rebaudioside A, are natural, non-caloric sweet-tasting organic molecules, present in extracts of the scrub plant Stevia rebaudiana, which are widely used as sweeteners in consumer foods and beverages. TRPM5 is a Ca2+-activated cation channel expressed in type II taste receptor cells and pancreatic β-cells. Here we show that stevioside, rebaudioside A and their aglycon steviol potentiate the activity of TRPM5. We find that SGs potentiate perception of bitter, sweet and umami taste, and enhance glucose-induced insulin secretion in a Trpm5-dependent manner. Daily consumption of stevioside prevents development of high-fat-diet-induced diabetic hyperglycaemia in wild-type mice, but not in Trpm5−/− mice. These results elucidate a molecular mechanism of action of SGs and identify TRPM5 as a potential target to prevent and treat type 2 diabetes. PMID:28361903
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Lin, Long-Ze; Mukhopadhyay, Sudarsan; Robbins, Rebecca J.; Harnly, James M.
2013-01-01
LC-DAD-ESI/MS was used to identify 23 flavonoids in the extract of Mexican oregano (Lippia graveolens H.B.K.), a spice and herb, used in the USA and Mexico. The identification of luteolin-7-O-glucoside, apigenin 7-O-glucoside, phloridzin, taxifolin, eriodictyol, scutellarein, luteolin, quercetin, naringenin, pinocembrin and galangin was confirmed by direct comparison with standards. Identification of 6-hydroxyluteolin, two 6-hydroxyluteolin 7-O-glycosides, three pentahydroxyflavanone hexosides, scutellarein 7-O-hexoside, 3-hydroxyphloretin hexoside, and three other flavones, was made by detailed analysis of their UV and mass spectral data. The identification of the flavonoid glycosides was further confirmed through detection of their aglycones following hydrolysis of the samples. The concentration of the identified flavonoids in three samples was also estimated. This is the first report of detection of over 20 flavonoids, including chalcones, in this plant material. PMID:24812440
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Potential hypoglycaemic activity phenolic glycosides from Moringa oleifera seeds.
Wang, Fang; Zhong, Huan-Huan; Chen, Wei-Ke; Liu, Qing-Pu; Li, Cun-Yu; Zheng, Yun-Feng; Peng, Guo-Ping
2017-08-01
Moringa oleifera seed has remarkable curative effects on reducing blood pressure, blood sugar and enhancing human immunity. In this study, one novel phenolic glycoside (1) together with four known compounds 2-5 were isolated from the macroporous resin adsorption extract of M. oleifera seeds, and the compound 3 was reported for the first time from this plant. The structure of the new crystalline compound was determined on the basis of spectroscopic analyses including mass spectrometry, 1D and 2D NMR experiments. The hypoglycaemic activity of isolated compounds was investigated with HepG2 cell and STZ-induced mice. It was found that compound 1, 4 and 5 could promote the glucose consumption of insulin resistance cells and reduce blood glucose levels of STZ-induced mice. This study concludes that compound 1, 4 and 5 may be developed as new and safe hypoglycaemic drugs.
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Bio- and chemical syntheses of mangiferin and congeners.
Ehianeta, Teddy Stephen; Laval, Stéphane; Yu, Biao
2016-09-10
Mangiferin (2C-β-d-glucopyranosyl-1,3,6,7-tetrahydroxyxanthone) is a xanthone C-glycoside occurring in many plant species. Composed of a glucose unit C1→2 linked to a 1,3,6,7-tetrahydroxyxanthone aglycone, mangiferin exhibits a wide range of biological activities, which recently renewed its interest as a potential pharmacophore. Mangiferin is mainly isolated after extraction procedures from natural sources alongside with its isoforms isomangiferin, homomangiferin, and neomangiferin. However, enzymatic and chemical approaches have been developed to access these phytochemicals, which address the challenging construction of the C-glycosidic linkage. In addition, both approaches have been exploited to modify the aglycone and the sugar moiety in order to afford analogues with specific and improved pharmacological activities. Herein, we provide a comprehensive review on the biosynthesis and chemical synthesis of mangiferin and its congeners. © 2016 BioFactors, 42(5):445-458, 2016. © 2016 International Union of Biochemistry and Molecular Biology.
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USDA-ARS?s Scientific Manuscript database
In the arms race between plants, herbivores, and their natural enemies, specialized herbivores may use plant defenses for their own benefit. In such cases, variation in secondary chemistry among host plants may affect the benefits that herbivores derive from these defenses. Caterpillars of Pieris br...
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Truchado, Pilar; Vit, Patricia; Ferreres, Federico; Tomas-Barberan, Francisco
2011-10-21
The analysis of the phytochemicals present in stingless bee honey samples has been a difficult task due to the small amounts of samples available and to the complexity of the phytochemical composition that often combines flavonoid glycosides and aglycones. Honey samples produced in Venezuela from Melipona species were analyzed using a combination of solid-phase extraction and HPLC-DAD-MSn/ESI methodologies with specific study of the fragment ions produced from flavonoid glycosides. The analyses revealed that flavonoid glycosides were the main constituents. The honey samples analyzed contained a consistent flavonoid pattern composed of flavone-C-glycosides, flavonol-O-glycosides and flavonoid aglycones. The HPLC-DAD-MSn/ESI analysis and the study of the fragment ions obtained allowed the characterization and quantification for the first time of five apigenin-di-C-glycosides, and ten quercetin, kaempferol and isorhamnetin O-glycosides (di- and tri- glycosides), and the aglycones pinobanksin, quercetin, kaempferol and isorhamnetin in the different samples. This is the first report of flavonoid-C-glycosides in honey. The results show that the content of flavonoid-glycosides (mean values of 2712 μg/100 g) in stingless bee honeys is considerably higher than the content of flavonoid aglycones (mean values of 315 μg/100 g). This differs from previous studies on Apis mellifera honeys that consistently showed much higher aglycone content and smaller flavonoid glycoside content. The occurrence of relevant amounts of flavonoid glycosides, and particularly C-glycosides, in stingless bee honeys could be associated with their putative anticataract properties. Copyright © 2011 Elsevier B.V. All rights reserved.
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Mehrabi, Zia; Bell, Thomas; Lewis, Owen T
2015-06-01
Intraspecific negative feedback effects, where performance is reduced on soils conditioned by conspecifics, are widely documented in plant communities. However, interspecific feedbacks are less well studied, and their direction, strength, causes, and consequences are poorly understood. If more closely related species share pathogens, or have similar soil resource requirements, plants may perform better on soils conditioned by more distant phylogenetic relatives. There have been few empirical tests of this prediction across plant life stages, and none of which attempt to account for soil chemistry. Here, we test the utility of phylogeny for predicting soil feedback effects on plant survival and performance (germination, seedling survival, growth rate, biomass). We implement a full factorial experiment growing species representing five families on five plant family-specific soil sources. Our experiments exploit soils that have been cultured for over 30 years in plant family-specific beds at Oxford University Botanic Gardens. Plant responses to soil source were idiosyncratic, and species did not perform better on soils cultured by phylogenetically more distant relatives. The magnitude and sign of feedback effects could, however, be explained by differences in the chemical properties of "home" and "away" soils. Furthermore, the direction of soil chemistry-related plant-soil feedbacks was dependent on plant life stage, with the effects of soil chemistry on germination success and accumulation of biomass inversely related. Our results (1) suggest that the phylogenetic distance between plant families cannot predict plant-soil feedbacks across multiple life stages, and (2) highlight the need to consider changes in soil chemistry as an important driver of population responses. The contrasting responses at plant life stages suggest that studies focusing on brief phases in plant demography (e.g., germination success) may not give a full picture of plant-soil feedback effects.
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[Studies on the flavonoids from Dendranthema lavandulifolium].
Shen, Y X; Quan, L H; Guan, L; Chen, J M
1997-06-01
From the whole plant of Dendranthema lavandulifolium, two flavonoides (I, II) and two flavone glycosides (III, IV) were isolated. They were identified as luteolin (I), apigenin (II), 5-hydroxy-4'-methoxy-flavone-7-O-alpha-L-rhamnopyranosyl(1-->6)-beta- D-glucopyranosyl (acaciin III) and 5-hydroxy-4'-methoxy-flavone-7-O-alpha-L-rhamnopyranosyl (1-->6) [2-O-acetyl-beta-D-glucopyranosyl(1-->2)]-beta-D-glucopyranoside (IV) by means of IR, UV, 1H-NMR, 13C-NMR, EI-MS, HRFAB, etc. Among these four compounds, I, II were isolated for the first time from this plant, IV is a new compound.
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Schmidt, Susanne; Zietz, Michaela; Schreiner, Monika; Rohn, Sascha; Kroh, Lothar W; Krumbein, Angelika
2010-07-30
Kale is a member of the Brassicaceae family and has a complex profile of flavonoid glycosides. Therefore, kale is a suitable matrix to discuss in a comprehensive study the different fragmentation patterns of flavonoid glycosides. The wide variety of glycosylation and acylation patterns determines the health-promoting effects of these glycosides. The aim of this study is to investigate the naturally occurring flavonoids in kale. A total of 71 flavonoid glycosides of quercetin, kaempferol and isorhamnetin were identified using a high-performance liquid chromatography diode-array detection/electrospray ionization multi-stage mass spectrometry (HPLC-DAD/ESI-MS(n)) method. Of these 71 flavonol glycosides, 27 were non-acylated, 30 were monoacylated and 14 were diacylated. Non-acylated flavonol glycosides were present as mono-, di-, tri- and tetraglycosides. This is the first time that the occurrence of four different fragmentation patterns of non-acylated flavonol triglycosides has been reported in one matrix simultaneously. In addition, 44 flavonol glycosides were acylated with p-coumaric, caffeic, ferulic, hydroxyferulic or sinapic acid. While monoacylated glycosides existed as di-, tri- and tetraglycosides, diacylated glycosides occurred as tetra- and pentaglycosides. To the best of our knowledge, 28 compounds in kale are reported here for the first time. These include three acylated isorhamnetin glycosides (isorhamnetin-3-O-sinapoyl-sophoroside-7-O-D-glucoside, isorhamnetin-3-O-feruloyl-sophoroside-7-O-diglucoside and isorhamnetin-3-O-disinapoyl-triglucoside-7-O-diglucoside) and seven non-acylated isorhamnetin glycosides. Copyright 2010 John Wiley & Sons, Ltd.
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Perspectives for the industrial enzymatic production of glycosides.
de Roode, B Mattheus; Franssen, Maurice C R; van der Padt, Albert; Boom, Remko M
2003-01-01
Glycosides are of commercial interest for industry in general and specifically for the pharmaceutical and food industry. Currently chemical preparation of glycosides will not meet EC food regulations, and therefore chemical preparation of glycosides is not applicable in the food industry. Thus, enzyme-catalyzed reactions are a good alternative. However, until now the low yields obtained by enzymatic methods prevent the production of glycosides on a commercial scale. Therefore, high yields should be established by a combination of optimum reaction conditions and continuous removal of the product. Unfortunately, a bioreactor for the commercial scale production of glycosides is not available. The aim of this article is to discuss the literature with respect to enzymatic production of glycosides and the design of an industrially viable bioreactor system.
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Barbet-Massin, Claire; Giuliano, Simon; Alletto, Lionel; Daydé, Jean; Berger, Monique
2015-01-01
The need for medicinal and aromatic plants for industrial uses creates an opportunity for farmers to produce alternative crops. Stevia rebaudiana Bertoni, a perennial shrub originating from Paraguay, is of increasing interest as a source of zero-calorie natural sweeteners: the steviol glycosides (SVglys). The aim of this study was to investigate the relevance of nitrogen (N) supply for leaf yield and for SVgly concentrations in leaves, which are the two major components of S. rebaudiana productivity. In this regard, the relationship between leaf N concentration, CO2 assimilation, leaf production and SVgly accumulation was investigated. The experiments were conducted consecutively in growth-chamber (CC: controlled conditions), in greenhouse (SCC: semi-controlled conditions) and in field conditions (FC) on two genotypes. In CC and SCC, three levels of N fertilization were applied. Plants were grown on four locations in the FC experiment. Both N supply (CC and SCC) and location (FC) had a significant effect on N content in leaves. When light was not limiting (SCC and FC) N content in leaves was positively correlated with CO2 assimilation rate and biomass accumulation. Irrespective of the growth conditions, N content in leaves was negatively correlated with SVgly content. However, increased SVgly content was correlated with a decreased ratio of rebaudioside A over stevioside. The evidence that the increased SVgly accumulation compensates for the negative effect on biomass production suggests that adequate SVgly productivity per plant may be achieved with relatively low fertilization. PMID:26192921
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Snapshot of the Eukaryotic Gene Expression in Muskoxen Rumen—A Metatranscriptomic Approach
O'Toole, Nicholas; Barboza, Perry S.; Ungerfeld, Emilio; Leigh, Mary Beth; Selinger, L. Brent; Butler, Greg; Tsang, Adrian; McAllister, Tim A.; Forster, Robert J.
2011-01-01
Background Herbivores rely on digestive tract lignocellulolytic microorganisms, including bacteria, fungi and protozoa, to derive energy and carbon from plant cell wall polysaccharides. Culture independent metagenomic studies have been used to reveal the genetic content of the bacterial species within gut microbiomes. However, the nature of the genes encoded by eukaryotic protozoa and fungi within these environments has not been explored using metagenomic or metatranscriptomic approaches. Methodology/Principal Findings In this study, a metatranscriptomic approach was used to investigate the functional diversity of the eukaryotic microorganisms within the rumen of muskoxen (Ovibos moschatus), with a focus on plant cell wall degrading enzymes. Polyadenylated RNA (mRNA) was sequenced on the Illumina Genome Analyzer II system and 2.8 gigabases of sequences were obtained and 59129 contigs assembled. Plant cell wall degrading enzyme modules including glycoside hydrolases, carbohydrate esterases and polysaccharide lyases were identified from over 2500 contigs. These included a number of glycoside hydrolase family 6 (GH6), GH48 and swollenin modules, which have rarely been described in previous gut metagenomic studies. Conclusions/Significance The muskoxen rumen metatranscriptome demonstrates a much higher percentage of cellulase enzyme discovery and an 8.7x higher rate of total carbohydrate active enzyme discovery per gigabase of sequence than previous rumen metagenomes. This study provides a snapshot of eukaryotic gene expression in the muskoxen rumen, and identifies a number of candidate genes coding for potentially valuable lignocellulolytic enzymes. PMID:21655220
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Taiwo, Bamigboye J; Olubiyi, Olujide O; van Heerden, Fanie R
2018-03-20
Nigerian medicinal plants have been demonstrated to be veritable source of lead compounds for drug discovery efforts. One such example is mangiferin. Mangiferin was originally isolated from the Nigerian plant Ceiba pentandra (Mombacaceae), after which its structure was elucidated with the aid of spectroscopy. Mangiferin, a xanthone glycoside, has also been reported in certain other plant families including Gentianaceae and Anacardiaceae. In certain other climes and different parts of the world, folkloric and traditional medicine has extensively employed Mangifera indica (another source of mangiferin) in treating different diseases. For many of such cultural uses carefully designed experimental investigations have been conducted confirming mangiferin's efficacies in those different pathologies which have included but not limited to cytotoxic as well as chemopreventive properties in selected cancer cell lines. In this study, computational techniques were employed to profile the interaction of the xanthone glycoside at the atomistic level against nine selected molecular targets with clinical relevance in tumorigenesis. In attempt to investigate the potential of the mangiferin structure as a viable starting point for synthetic exploration of mangiferin-based analogs, extensive structural modifications were performed. By analyzing the resulting structure-energetic pattern, critical points capable of improving mangiferin interaction with the profiled targets were identified. The outcome of this study provides both direction and impetus for synthetic derivitization of the mangiferin molecule into novel optimized inhibitors for anticancer lead development. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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Agrawal, Anurag A; Weber, Marjorie G
2015-10-01
Species comparisons are a cornerstone of biology and there is a long tradition of using the comparative framework to study the ecology and evolution of plant defensive traits. Early comparative studies led to the hypothesis that plant chemistry plays a central role in plant defence, and the evolution of plant secondary chemistry in response to insect herbivory remains a classic example of coevolution. However, recent comparative work has disagreed with this paradigm, reporting little connection between plant secondary chemicals and herbivory across distantly related plant taxa. One conclusion of this new work is that the importance of secondary chemistry in plant defence may have been generally overstated in earlier research. Here, we attempt to reconcile these contradicting viewpoints on the role of plant chemistry in defence by critically evaluating the use and interpretation of species correlations as a means to study defence-herbivory relationships. We conclude that the notion that plant primary metabolites (e.g. leaf nitrogen content) are the principal determinants of herbivory (or the target of natural selection by herbivores) is not likely to be correct. Despite the inference of recent community-wide studies of herbivory, strong evidence remains for a prime role of secondary compounds in plant defence against herbivores. © 2015 John Wiley & Sons Ltd/CNRS.
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Direct and indirect effects of invasive plants on soil chemistry and ecosystem function.
Weidenhamer, Jeffrey D; Callaway, Ragan M
2010-01-01
Invasive plants have a multitude of impacts on plant communities through their direct and indirect effects on soil chemistry and ecosystem function. For example, plants modify the soil environment through root exudates that affect soil structure, and mobilize and/or chelate nutrients. The long-term impact of litter and root exudates can modify soil nutrient pools, and there is evidence that invasive plant species may alter nutrient cycles differently from native species. The effects of plants on ecosystem biogeochemistry may be caused by differences in leaf tissue nutrient stoichiometry or secondary metabolites, although evidence for the importance of allelochemicals in driving these processes is lacking. Some invasive species may gain a competitive advantage through the release of compounds or combinations of compounds that are unique to the invaded community—the “novel weapons hypothesis.” Invasive plants also can exert profound impact on plant communities indirectly through the herbicides used to control them. Glyphosate, the most widely used herbicide in the world, often is used to help control invasive weeds, and generally is considered to have minimal environmental impacts. Most studies show little to no effect of glyphosate and other herbicides on soil microbial communities. However, herbicide applications can reduce or promote rhizobium nodulation and mycorrhiza formation. Herbicide drift can affect the growth of non-target plants, and glyphosate and other herbicides can impact significantly the secondary chemistry of plants at sublethal doses. In summary, the literature indicates that invasive species can alter the biogeochemistry of ecosystems, that secondary metabolites released by invasive species may play important roles in soil chemistry as well as plant-plant and plant-microbe interactions, and that the herbicides used to control invasive species can impact plant chemistry and ecosystems in ways that have yet to be fully explored.
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The logic of automated glycan assembly.
Seeberger, Peter H
2015-05-19
Carbohydrates are the most abundant biopolymers on earth and part of every living creature. Glycans are essential as materials for nutrition and for information transfer in biological processes. To date, in few cases a detailed correlation between glycan structure and glycan function has been established. A molecular understanding of glycan function will require pure glycans for biological, immunological, and structural studies. Given the immense structural complexity of glycans found in living organisms and the lack of amplification methods or expression systems, chemical synthesis is the only means to access usable quantities of pure glycan molecules. While the solid-phase synthesis of DNA and peptides has become routine for decades, access to glycans has been technically difficult, time-consuming and confined to a few expert laboratories. In this Account, the development of a comprehensive approach to the automated synthesis of all classes of mammalian glycans, including glycosaminoglycans and glycosylphosphatidyl inositol (GPI) anchors, as well as bacterial and plant carbohydrates is described. A conceptual advance concerning the logic of glycan assembly was required in order to enable automated execution of the synthetic process. Based on the central glycosidic bond forming reaction, a general concept for the protecting groups and leaving groups has been developed. Building blocks that can be procured on large scale, are stable for prolonged periods of time, but upon activation result in high yields and selectivities were identified. A coupling-capping and deprotection cycle was invented that can be executed by an automated synthesis instrument. Straightforward postsynthetic protocols for cleavage from the solid support as well as purification of conjugation-ready oligosaccharides have been established. Introduction of methods to install selectively a wide variety of glycosidic linkages has enabled the rapid assembly of linear and branched oligo- and polysaccharides as large as 30-mers. Fast, reliable access to defined glycans that are ready for conjugation has given rise to glycan arrays, glycan probes, and synthetic glycoconjugate vaccines. While an ever increasing variety of glycans are accessible by automated synthesis, further methodological advances in carbohydrate chemistry are needed to make all possible glycans found in nature. These tools begin to fundamentally impact the medical but also materials aspects of the glycosciences.
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USDA-ARS?s Scientific Manuscript database
Two new prenylated flavonol glycosides, epimedigrandiosides A and B (1 and 2), and 28 previously known compounds including prenylated flavonol derivatives, flavonol glycoside, megastigmanes, phenyl alkanoids, sesquiterpenoid glycoside, lignan, and hexene glucoside were isolated from the methanol ext...
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Sea Cucumber Glycosides: Chemical Structures, Producing Species and Important Biological Properties.
Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Rahman, M Aminur; Islam, Mohamad Tofazzal
2017-10-17
Sea cucumbers belonging to echinoderm are traditionally used as tonic food in China and other Asian countries. They produce abundant biologically active triterpene glycosides. More than 300 triterpene glycosides have been isolated and characterized from various species of sea cucumbers, which are classified as holostane and nonholostane depending on the presence or absence of a specific structural unit γ(18,20)-lactone in the aglycone. Triterpene glycosides contain a carbohydrate chain up to six monosaccharide units mainly consisting of d-xylose, 3-O-methy-d-xylose, d-glucose, 3-O-methyl-d-glucose, and d-quinovose. Cytotoxicity is the common biological property of triterpene glycosides isolated from sea cucumbers. Besides cytotoxicity, triterpene glycosides also exhibit antifungal, antiviral and hemolytic activities. This review updates and summarizes our understanding on diverse chemical structures of triterpene glycosides from various species of sea cucumbers and their important biological activities. Mechanisms of action and structural-activity relationships (SARs) of sea cucumber glycosides are also discussed briefly.
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Sea Cucumber Glycosides: Chemical Structures, Producing Species and Important Biological Properties
Mondol, Muhammad Abdul Mojid; Shin, Hee Jae; Rahman, M. Aminur; Islam, Mohamad Tofazzal
2017-01-01
Sea cucumbers belonging to echinoderm are traditionally used as tonic food in China and other Asian countries. They produce abundant biologically active triterpene glycosides. More than 300 triterpene glycosides have been isolated and characterized from various species of sea cucumbers, which are classified as holostane and nonholostane depending on the presence or absence of a specific structural unit γ(18,20)-lactone in the aglycone. Triterpene glycosides contain a carbohydrate chain up to six monosaccharide units mainly consisting of d-xylose, 3-O-methy-d-xylose, d-glucose, 3-O-methyl-d-glucose, and d-quinovose. Cytotoxicity is the common biological property of triterpene glycosides isolated from sea cucumbers. Besides cytotoxicity, triterpene glycosides also exhibit antifungal, antiviral and hemolytic activities. This review updates and summarizes our understanding on diverse chemical structures of triterpene glycosides from various species of sea cucumbers and their important biological activities. Mechanisms of action and structural–activity relationships (SARs) of sea cucumber glycosides are also discussed briefly. PMID:29039760
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USDA-ARS?s Scientific Manuscript database
Flavonoids are well-known for their health benefits and can be found in nearly every plant. There are more than 5,000 known flavonoids existing in foods. Profiling flavonoids in natural products poses great challenges due to the diversity of flavonoids, the lack of commercially available standards, ...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Hiras, Jennifer; Wu, Yu -Wei; Deng, Kai
Glycoside hydrolases (GHs) are key enzymes in the depolymerization of plant-derived cellulose, a process central to the global carbon cycle and the conversion of plant biomass to fuels and chemicals. A limited number of GH families hydrolyze crystalline cellulose, often by a processive mechanism along the cellulose chain. During cultivation of thermophilic cellulolytic microbial communities, substantial differences were observed in the crystalline cellulose saccharification activities of supernatants recovered from divergent lineages. Comparative community proteomics identified a set of cellulases from a population closely related to actinobacterium Thermobispora bispora that were highly abundant in the most active consortium. Among the cellulasesmore » from T. bispora, the abundance of a GH family 12 (GH12) protein correlated most closely with the changes in crystalline cellulose hydrolysis activity. This result was surprising since GH12 proteins have been predominantly characterized as enzymes active on soluble polysaccharide substrates. Heterologous expression and biochemical characterization of the suite of T. bispora hydrolytic cellulases confirmed that the GH12 protein possessed the highest activity on multiple crystalline cellulose substrates and demonstrated that it hydrolyzes cellulose chains by a predominantly random mechanism. This work suggests that the role of GH12 proteins in crystalline cellulose hydrolysis by cellulolytic microbes should be reconsidered.« less
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Hiras, Jennifer; Wu, Yu -Wei; Deng, Kai; ...
2016-08-23
Glycoside hydrolases (GHs) are key enzymes in the depolymerization of plant-derived cellulose, a process central to the global carbon cycle and the conversion of plant biomass to fuels and chemicals. A limited number of GH families hydrolyze crystalline cellulose, often by a processive mechanism along the cellulose chain. During cultivation of thermophilic cellulolytic microbial communities, substantial differences were observed in the crystalline cellulose saccharification activities of supernatants recovered from divergent lineages. Comparative community proteomics identified a set of cellulases from a population closely related to actinobacterium Thermobispora bispora that were highly abundant in the most active consortium. Among the cellulasesmore » from T. bispora, the abundance of a GH family 12 (GH12) protein correlated most closely with the changes in crystalline cellulose hydrolysis activity. This result was surprising since GH12 proteins have been predominantly characterized as enzymes active on soluble polysaccharide substrates. Heterologous expression and biochemical characterization of the suite of T. bispora hydrolytic cellulases confirmed that the GH12 protein possessed the highest activity on multiple crystalline cellulose substrates and demonstrated that it hydrolyzes cellulose chains by a predominantly random mechanism. This work suggests that the role of GH12 proteins in crystalline cellulose hydrolysis by cellulolytic microbes should be reconsidered.« less
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Apel, Lysanne; Kammerer, Dietmar R.; Stintzing, Florian C.; Spring, Otmar
2017-01-01
Primula veris L. is an important medicinal plant with documented use for the treatment of gout, headache and migraine reaching back to the Middle Ages. Triterpenoid saponins from roots and flowers are used in up-to-date phytotherapeutic treatment of bronchitis and colds due to their expectorant and secretolytic effects. In addition to the wild type plants with yellow petals, a red variant and an intermediate orange form of Primula veris L. have recently been found in a natural habitat. The secondary metabolite profiles of roots, leaves and flowers of these rare variants were investigated and compared with the wild type metabolome. Two flavonoids, six flavonoid glycosides, four novel methylated flavonoid glycosides, five anthocyanins and three triterpenoid saponins were identified in alcoholic extracts from the petals, leaves and roots of the three variants by high performance liquid chromatography (HPLC)-diode array detection (DAD)/mass spectrometry (MSn) analyses. Anthocyanins were detected in the petals of the red and orange variety, but not in the wild type. No other effects on the metabolite profiles of the three varieties have been observed. The possibility is discussed that a regulatory step of the anthocyanin biosynthetic pathway may have been affected by mutation thus triggering color polymorphism in the petals. PMID:28098796
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Kanazawa, Kazuki; Hashimoto, Takashi; Yoshida, Satoko; Sungwon, Park; Fukuda, Shinya
2012-05-02
It is desirable to increase the flavonoid contents of postharvest vegetables since flavonoids play a beneficial role in human health promotion. In the present study, we show that postharvest vegetables increasingly produced flavonoids when irradiated with light near the absorption wavelength of flavonoids in the plant. Three-day exposure to UV-B for 5 min, 98 μmol m⁻² s⁻¹ per day, increased the contents of jaceidin in spinach, kaempherol glycoside in radish sprout, apigenin glycosides in parsley, and isovitexin in Indian spinach after 6 days of storage in a refrigerator, compared to the contents in plants without irradiation. Six days of storage of unripe green strawberry under green light for 5 min, 98 μmol m⁻² s⁻¹ per day, enabled them to mature and turn red, accompanied by 3.5-fold increased contents of pelargonidin. Elucidation of the mechanism in parsley found the stimulating expression of the flavonoid synthesis gene, PAL, C4H, 4CL, CHS, and FNS, 6 h after exposure to single irradiation with UV-B for 5 min, and the higher expression was maintained for 24 h. After 3 days irradiation during 6 days of storage, parsley did not show adverse changes in the contents of ascorbic acid, β-carotene, chlorophyll, and moisture.
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Tiwari, Pragya; Sangwan, Rajender Singh; Asha; Mishra, B N; Sabir, Farzana; Sangwan, Neelam S
2014-01-01
Gymnema sylvestre R.Br., a pharmacologically important herb vernacularly called Gur-Mar (sugar eliminator), is widely known for its antidiabetic action. This property of the herb has been attributed to the presence of bioactive triterpene glycosides. Although some information regarding pharmacology and phytochemical profiles of the plant are available, no attempts have been made so far to decipher the biosynthetic pathway and key enzymes involved in biosynthesis of steryl glucosides. The present report deals with the identification and catalytic characterization of a glucosyltransferase, catalyzing biosynthesis of steryl glycosides. The full length cDNA (2572 bp) contained an open reading frame of 2106 nucleotides that encoded a 701 amino acid protein, falling into GT-B subfamily of glycosyltransferases. The GsSGT was expressed in Escherichia coli and biochemical characterization of the recombinant enzyme suggested its key role in the biosynthesis of steryl glucosides with catalytic preference for C-3 hydroxyl group of sterols. To our knowledge, this pertains to be the first report on cloning and biochemical characterization of a sterol metabolism gene from G. sylvestre R.Br. catalyzing glucosylation of a variety of sterols of biological origin from diverse organisms such as bacteria, fungi, and plants.
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Sangwan, Rajender Singh; Asha; Mishra, B. N.; Sangwan, Neelam S.
2014-01-01
Gymnema sylvestre R.Br., a pharmacologically important herb vernacularly called Gur-Mar (sugar eliminator), is widely known for its antidiabetic action. This property of the herb has been attributed to the presence of bioactive triterpene glycosides. Although some information regarding pharmacology and phytochemical profiles of the plant are available, no attempts have been made so far to decipher the biosynthetic pathway and key enzymes involved in biosynthesis of steryl glucosides. The present report deals with the identification and catalytic characterization of a glucosyltransferase, catalyzing biosynthesis of steryl glycosides. The full length cDNA (2572 bp) contained an open reading frame of 2106 nucleotides that encoded a 701 amino acid protein, falling into GT-B subfamily of glycosyltransferases. The GsSGT was expressed in Escherichia coli and biochemical characterization of the recombinant enzyme suggested its key role in the biosynthesis of steryl glucosides with catalytic preference for C-3 hydroxyl group of sterols. To our knowledge, this pertains to be the first report on cloning and biochemical characterization of a sterol metabolism gene from G. sylvestre R.Br. catalyzing glucosylation of a variety of sterols of biological origin from diverse organisms such as bacteria, fungi, and plants. PMID:25250339
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Cydonia oblonga M., A Medicinal Plant Rich in Phytonutrients for Pharmaceuticals
Ashraf, Muhammad U.; Muhammad, Gulzar; Hussain, Muhammad A.; Bukhari, Syed N. A.
2016-01-01
Cydonia oblonga M. is a medicinal plant of family Rosaceae which is used to prevent or treat several ailments such as cancer, diabetes, hepatitis, ulcer, respiratory, and urinary infections, etc. Cydonia oblonga commonly known as Quince is rich in useful secondary metabolites such as phenolics, steroids, flavonoids, terpenoids, tannins, sugars, organic acids, and glycosides. A wide range of pharmacological activities like antioxidant, antibacterial, antifungal, anti-inflammatory, hepatoprotective, cardiovascular, antidepressant, antidiarrheal, hypolipidemic, diuretic, and hypoglycemic have been ascribed to various parts of C. oblonga. The polysaccharide mucilage, glucuronoxylan extruded from seeds of C. oblonga is used in dermal patches to heal wounds. This review focuses on detailed investigations of high-valued phytochemicals as well as pharmacological and phytomedicinal attributes of the plant. PMID:27445806
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Blazej, Robert; Toriello, Nicholas; Emrich, Charles; Cohen, Richard N.; Koppel, Nitzan
2015-07-14
This invention provides novel variant cellulolytic enzymes having improved activity and/or stability. In certain embodiments the variant cellulotyic enzymes comprise a glycoside hydrolase with or comprising a substitution at one or more positions corresponding to one or more of residues F64, A226, and/or E246 in Thermobifida fusca Cel9A enzyme. In certain embodiments the glycoside hydrolase is a variant of a family 9 glycoside hydrolase. In certain embodiments the glycoside hydrolase is a variant of a theme B family 9 glycoside hydrolase.
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Li, Hui-fang; Guan, Xiang-yu; Ye, Min; Xiang, Cheng; Lin, Chang-hu; Sun, Chao; Guo, De-an
2011-06-01
A new HPLC-DAD-ESI-MS(n) method was developed for rapid separation, characterization and quantitation of flavonoids in Epimedium wushanense, a popular Chinese herbal medicine. For qualitative identification, a total of 37 compounds were characterized from the underground and aerial parts of E. wushanense. Among them, 28 compounds were prenylated flavonoids, and 23 were confirmed by comparing with reference standards. For quantitative analysis, 12 major flavonoids including kaempferol glycosides, desmethylicaritin glycosides, and icaritin glycosides were simultaneously determined by HPLC/UV. Samples were separated on a Waters Symmetry C(18) column at 35 °C eluted with a gradient three-component mobile phase of acetonitrile, methanol, and water containing 0.03% v/v formic acid. All the flavonoids showed good linearity (r(2) ≥0.9997). The recoveries varied from 92.6 to 106.1% at three concentration levels. This method was applied to the determination of 20 samples of different geographical sources, harvesting time, and plant parts. Contents of the predominant flavonoid, epimedin C, ranged from 1.4 to 5.1% in aerial parts and 1.0 to 2.8% in underground parts. The methods established in this paper were simple and reliable and could be used for the quality control of E. wushanense. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Resin glycosides from Ipomoea pes-caprae.
Escobedo-Martínez, Carolina; Pereda-Miranda, Rogelio
2007-06-01
Ipomoea pes-caprae (beach morning-glory; "riñonina" for the herbal drug in Mexico) is prescribed by traditional healers to moderate "heat" in an infected kidney. The hexane-soluble extract from the aerial parts of this medicinal plant, through preparative-scale recycling HPLC, yielded six new lipophilic oligosaccharides of jalapinolic acid: pescaproside B (1) and pescapreins V-IX (2-6). The previously known pescaproside A (7), pescapreins I-IV (8-11), and stoloniferin III (12) were also identified in the analyzed material by means of HPLC comparison with authentic samples. The glycosidic acid structure for all pentasaccharides was confirmed as simonic acid B. Pescaproside B (1), an acylated glycosidic acid methyl ester, is structurally related to pescaprein III (10). Pescapreins V (2) and VI (3) are diasteroisomeric tetraglycosidic lactones of operculinic acid C. Both of these compounds contain (2S)-methylbutyric and n-dodecanoic acids as their esterifying residues. Pescapreins VII (4) and IX (6) are pentasaccharides that contain an n-decanoyl group as their esterifying fatty acid residue instead of the n-dodecanoyl found in pescapreins I (8) and IV (11). Pescaprein VIII (5) represents an isomer of pescaprein II (9) containing an n-dodecanoyl unit as the esterifying residue at position C-4 of the third rhamnose moiety and a 2-methylpropanoyl at C-2 of the second rhamnose. High-field NMR spectroscopy and FAB mass spectrometry were used to characterize all new isolated compounds.
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Avula, Bharathi; Wang, Yan-Hong; Smillie, Troy J; Khan, Ikhlas A
2009-03-01
A UPLC-UV/ELSD method has been developed for analysis of major triterpenoids and formononetin in ACTAEA RACEMOSA L. (family Ranunculaceae) samples. The best results were obtained with an Acquity UPLC BEH C18 (100 mmx2.1 mm, i. d., 1 microm) column system using gradient elution with a mobile phase consisting of water and acetonitrile:methanol (7:3) at a constant flow rate of 0.3 mL/min. Owing to their low UV absorption, the triterpene saponins were detected by evaporative light scattering. Within 5.5 minutes, three main triterpenoid glycosides [cimiracemoside A, 23- EPI-26-deoxyactein, and actein] and an isoflavonoid, formononetin, could be separated, with detection limits of 5, 5, 10, and 0.01 microg/mL, respectively. The method was successfully used to analyze different Actaea racemosa market products as well as to distinguish between two other ACTAEA species. There was a significant variability in the amounts of the selected triterpene glycosides for the products containing black cohosh and rhizomes of black cohosh. The isoflavone formononetin was not detected in the samples analyzed. LC-MS coupled with the electrospray ionization (ESI) interface method is described for the identification of formononetin and triterpenoid glycosides in plant samples and dietary supplements that claim to contain black cohosh and different species of Actaea.
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Plants and Medicinal Chemistry--2
ERIC Educational Resources Information Center
Bailey, D.
1977-01-01
Second of a two part article on the influence of plants on medicinal chemistry. This part considers how drugs work, the attempts to develop anaesthetics safer than cocaine, and useful poisons. (Author/SL)
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The chemistry of wine polyphenolic C-glycosidic ellagitannins targeting human topoisomerase II.
Quideau, Stéphane; Jourdes, Michael; Lefeuvre, Dorothée; Montaudon, Danièle; Saucier, Cédric; Glories, Yves; Pardon, Patrick; Pourquier, Philippe
2005-11-04
Polyphenolic nonahydroxyterphenoyl-containing C-glycosidic oak ellagitannins are found in wine as a result of the aging of this beverage in oak-made barrels. Once in the slightly acidic wine (pH approximately 3-4), some of these complex natural products such as (-)-vescalagin (1), but not its C-1 epimer (-)-castalagin (2), can capture grape-derived nucleophilic entities such as ethanol, the flavanols catechin (10a) and epicatechin (10b), the anthocyanin oenin (13b), and the thiolic glutathione (16) to furnish condensation products with retention of configuration at the C-1 locus. A computer-aided rationale of this high diastereoselectivity is given. These condensation products can contribute to the modulation of organoleptic properties of the wine, as evidenced by the 23 nm bathochromic shift color absorbance observed with the novel oenin-based anthocyano-ellagitannin (15b). Hydrolysis of 1 under solvolytic conditions furnished another novel compound that we refer to as vescalene (21), in addition to the known (-)-vescalin (18). Of pharmacological importance is the fact that most of these found-in-wine water-soluble ellagitannin derivatives are much more potent than etoposide (VP-16) at inhibiting top2-mediated DNA decatenation in vitro (top2=topoisomerase II)). The known (-)-vescalin (18) and the novel vescalene (21) fully inhibited top2 at 10 microM concentration!
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Determination of Plant Volatiles Using Solid Phase Microextraction GC-MS
ERIC Educational Resources Information Center
Van Bramer, Scott; Goodrich, Katherine R.
2015-01-01
This experiment combines analytical techniques of solid phase microextraction and gas chromatography-mass spectrometry with easily relatable and accessible plant volatile chemistry (floral and vegetative scents of local/available plants). The biosynthesis and structure of these chemicals are of interest in the areas of organic chemistry,…
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USDA-ARS?s Scientific Manuscript database
Objectives of the study were to determine effects of Fe source on plant growth, plant nutrition, substrate chemistry and runoff chemistry. Iron source (FS) treatments consisted of Fe-aminopolycarboxylic acid (APCA) complexones iron ethylenediaminetetraacetic acid (FeEDTA), iron [S, S']-ethylenediam...
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Aroma Glycosides in Grapes and Wine.
Liu, Jibin; Zhu, Xiao-Lin; Ullah, Niamat; Tao, Yong-Sheng
2017-02-01
The major aroma components in grapes and wine include free volatile compounds and glycosidic nonvolatile compounds. The latter group of compounds is more than 10 times abundant of the former, and constitutes a big aroma reserve in grapes and wine. This review summarizes the research results obtained recently for the identification of aroma glycosides in grapes and wine, including grape glycoside structures, differences in aroma glycosides among grape varieties, hydrolysis mechanisms, and the factors that influence them. It also presents the analytical techniques used to identify the glycosidic aroma precursors. The operational strategies, challenges, and improvements of each step encountered in the analysis of glycosidic aroma precursors are described. This review intends to provide a convenient reference for researchers interested in the methods used for the determination of the aroma glucosides composition and the recognition of their chemical structures. © 2017 Institute of Food Technologists®.
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Popov, Roman S; Ivanchina, Natalia V; Silchenko, Alexandra S; Avilov, Sergey A; Kalinin, Vladimir I; Dolmatov, Igor Yu; Stonik, Valentin A; Dmitrenok, Pavel S
2017-10-02
The Far Eastern sea cucumber Eupentacta fraudatrix is an inhabitant of shallow waters of the south part of the Sea of Japan. This animal is an interesting and rich source of triterpene glycosides with unique chemical structures and various biological activities. The objective of this study was to investigate composition and distribution in various body components of triterpene glycosides of the sea cucumber E. fraudatrix . We applied LC-ESI MS (liquid chromatography-electrospray mass spectrometry) of whole body extract and extracts of various body components for metabolic profiling and structure elucidation of triterpene glycosides from the E. fraudatrix . Totally, 54 compounds, including 26 sulfated, 18 non-sulfated and 10 disulfated glycosides were detected and described. Triterpene glycosides from the body walls, gonads, aquapharyngeal bulbs, guts and respiratory trees were extracted separately and the distributions of the detected compounds in various body components were analyzed. Series of new glycosides with unusual structural features were described in E. fraudatrix , which allow clarifying the biosynthesis of these compounds. Comparison of the triterpene glycosides contents from the five different body components revealed that the profiles of triterpene glycosides were qualitatively similar, and only some quantitative variabilities for minor compounds were observed.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Brady D.; Apel, William A.; Sheridan, Peter P.
Background Metabolism of carbon bound in wheat arabinoxylan (WAX) polysaccharides by bacteria requires a number of glycoside hydrolases active toward different bonds between sugars and other molecules. Alicyclobacillus acidocaldarius is a Gram-positive thermoacidophilic bacterium capable of growth on a variety of mono-, di-, oligo-, and polysaccharides. Nineteen proposed glycoside hydrolases have been annotated in the A. acidocaldarius Type Strain ATCC27009/DSM 446 genome. Results Molecular analysis using high-density oligonucleotide microarrays was performed on A. acidocaldarius strain ATCC27009 when growing on WAX. When a culture growing exponentially at the expense of arabinoxylan saccharides was challenged with glucose or xylose, most glycoside hydrolasesmore » were down-regulated. Interestingly, regulation was more intense when xylose was added to the culture than when glucose was added, a clear departure from classical carbon catabolite repression demonstrated by many Gram-positive bacteria. In silico analyses of the regulated glycoside hydrolases, along with the results from the microarray analyses, yielded a potential mechanism for arabinoxylan metabolism by A. acidocaldarius. Glycoside hydrolases expressed by this strain may have broad substrate specificity, and initial hydrolysis is catalyzed by an extracellular xylanase, while subsequent steps are likely performed inside the growing cell. Conclusions Glycoside hydrolases, for the most part, appear to be found in clusters, throughout the A. acidocaldarius genome. Not all of the glycoside hydrolase genes found at loci within these clusters were regulated during the experiment, indicating that a specific subset of the 19 glycoside hydrolase genes found in A. acidocaldarius were used during metabolism of WAX. While specific functions of the glycoside hydrolases was not tested as part of the research discussed, many of the glycoside hydrolases found in the A. acidocaldarius Type Strain appear to have a broader substrate range than represented by the glycoside hydrolase family in which the enzymes were categorized.« less
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Flavonol glycosides in the petal of Rosa species as chemotaxonomic markers.
Sarangowa, Ochir; Kanazawa, Tsutomu; Nishizawa, Makoto; Myoda, Takao; Bai, Changxi; Yamagishi, Takashi
2014-11-01
Thirteen flavonol glycosides were isolated from the petals of Rosa species belonging to the section Gallicanae, and their structures were identified from their spectroscopic data. These flavonol glycosides, along with two flavonol glycosides isolated from Rosa rugosa, in the petals of 31 Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae were quantitatively analyzed by UPLC. The results indicated that the species belonging to these sections could be classified into four types (Type A, B, C and D) based on the pattern of flavonol glycoside contents, whereas the R. rugosa flavonol glycosides were detected only in section Cinnamomeae. A principal components analysis (PCA) calculated from the 15 flavonol glycosides contained in these samples supported the presence of four types. The distribution of the species in Type D (a group of Cinnamomeae) was shown to reflect close interrelationships, but species in Type B (one group of Gallicanae) could be subdivided into two groups, one of which contained species in section Synstylae. Moreover, the flavonol glycosides were grouped by sugar moieties: a disaccharide composed of two hexoses (S1), a hexose (S2), including a hexose with galloyl group, a pentose (S3), and a disaccharide composed of a hexose and a pentose (S4). The ratios of the amounts of S1-S4 to total flavonol glycoside content indicated that differences among the four sections were more distinctive than the amounts of the 15 flavonol glycosides. The 31 samples were divided into Type B, composed of one type of Gallicanae and Synstylae, Type A+C, composed of another type of Gallicanae and Caninae, and Type D, composed of Cinnamomeae. The R. rugosa flavonol glycosides were shown to be important chemotaxonomic markers for the classification of species in Cinnamomeae, and this method of using flavonol glycosides as chemotaxonomic markers could be useful for the identification of Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae. Copyright © 2014 Elsevier Ltd. All rights reserved.
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19. VIEW OF THE GENERAL CHEMISTRY LABORATORY IN BUILDING 881. ...
19. VIEW OF THE GENERAL CHEMISTRY LABORATORY IN BUILDING 881. (4/12/62) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO
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Intelligent Chemistry Management System (ICMS)--A new approach to steam generator chemistry control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barto, R.J.; Farrell, D.M.; Noto, F.A.
1986-04-01
The Intelligent Chemistry Management System (ICMS) is a new tool which assists in steam generator chemistry control. Utilizing diagnostic capabilities, the ICMS will provide utility and industrial boiler operators, system chemists, and plant engineers with a tool for monitoring, diagnosing, and controlling steam generator system chemistry. By reducing the number of forced outages through early identification of potentially detrimental conditions, suggestion of possible causes, and execution of corrective actions, improvements in unit availability and reliability will result. The system monitors water and steam quality at a number of critical locations in the plant.
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Lohaus, Gertrud; Schwerdtfeger, Michael
2014-01-01
Background Floral nectar contains sugars and amino acids to attract pollinators. In addition, nectar also contains different secondary compounds, but little is understood about their origin or function. Does nectar composition reflect phloem composition, or is nectar synthesized and/or modified in nectaries? Studies where both, the nectar as well as the phloem sap taken from the same plant species were analyzed in parallel are rare. Therefore, phloem sap and nectar from different plant species (Maurandya barclayana, Lophospermum erubescens, and Brassica napus) were compared. Methodology and Principal Findings Nectar was collected with microcapillary tubes and phloem sap with the laser-aphid-stylet technique. The nectar of all three plant species contained high amounts of sugars with different percentages of glucose, fructose, and sucrose, whereas phloem sap sugars consisted almost exclusively of sucrose. One possible reason for this could be the activity of invertases in the nectaries. The total concentration of amino acids was much lower in nectars than in phloem sap, indicating selective retention of nitrogenous solutes during nectar formation. Nectar amino acid concentrations were negatively correlated with the nectar volumes per flower of the different plant species. Both members of the tribe Antirrhineae (Plantaginaceae) M. barclayana and L. erubescens synthesized the iridoid glycoside antirrhinoside. High amounts of antirrhinoside were found in the phloem sap and lower amounts in the nectar of both plant species. Conclusions/Significance The parallel analyses of nectar and phloem sap have shown that all metabolites which were found in nectar were also detectable in phloem sap with the exception of hexoses. Otherwise, the composition of both aqueous solutions was not the same. The concentration of several metabolites was lower in nectar than in phloem sap indicating selective retention of some metabolites. Furthermore, the existence of antirrhinoside in nectar could be based on passive secretion from the phloem. PMID:24489951
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Lohaus, Gertrud; Schwerdtfeger, Michael
2014-01-01
Floral nectar contains sugars and amino acids to attract pollinators. In addition, nectar also contains different secondary compounds, but little is understood about their origin or function. Does nectar composition reflect phloem composition, or is nectar synthesized and/or modified in nectaries? Studies where both, the nectar as well as the phloem sap taken from the same plant species were analyzed in parallel are rare. Therefore, phloem sap and nectar from different plant species (Maurandya barclayana, Lophospermum erubescens, and Brassica napus) were compared. Nectar was collected with microcapillary tubes and phloem sap with the laser-aphid-stylet technique. The nectar of all three plant species contained high amounts of sugars with different percentages of glucose, fructose, and sucrose, whereas phloem sap sugars consisted almost exclusively of sucrose. One possible reason for this could be the activity of invertases in the nectaries. The total concentration of amino acids was much lower in nectars than in phloem sap, indicating selective retention of nitrogenous solutes during nectar formation. Nectar amino acid concentrations were negatively correlated with the nectar volumes per flower of the different plant species. Both members of the tribe Antirrhineae (Plantaginaceae) M. barclayana and L. erubescens synthesized the iridoid glycoside antirrhinoside. High amounts of antirrhinoside were found in the phloem sap and lower amounts in the nectar of both plant species. The parallel analyses of nectar and phloem sap have shown that all metabolites which were found in nectar were also detectable in phloem sap with the exception of hexoses. Otherwise, the composition of both aqueous solutions was not the same. The concentration of several metabolites was lower in nectar than in phloem sap indicating selective retention of some metabolites. Furthermore, the existence of antirrhinoside in nectar could be based on passive secretion from the phloem.
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Organic Chemistry and the Native Plants of the Sonoran Desert: Conversion of Jojoba Oil to Biodiesel
ERIC Educational Resources Information Center
Daconta, Lisa V.; Minger, Timothy; Nedelkova, Valentina; Zikopoulos, John N.
2015-01-01
A new, general approach to the organic chemistry laboratory is introduced that is based on learning about organic chemistry techniques and research methods by exploring the natural products found in local native plants. As an example of this approach for the Sonoran desert region, the extraction of jojoba oil and its transesterification to…
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Hu, Youcai; Qu, Jing; Liu, Yuanyan; Yu, Shishan; Li, Jianbei; Zhang, Jinlan; Du, Dan
2010-01-01
The mass fragmentation patterns of stilbene glycosides isolated from the genus Lysidice were investigated by negative ion electrospray ionization tandem mass spectrometry, and the influence of collision energy on their fragmentation behavior is discussed. It is found that the presence of the Y(0)(-) and B(0)(-) ions in the MS(2) spectra is characteristic for 1-->6 linked diglycosyl stilbenes, while the Y(0)(-), Y(1)(-), and Z(1)(-) ions are representative ions of 1-->2 linked diglycosyl stilbenes. These results indicate that ESI-MS(n) in the negative ion mode can be used to differentiate 1-->6 and 1-->2 linked diglycosyl stilbenes. Based on the fragmentation rules, 9 new trace constituents were identified or tentatively characterized in a fraction of Lysidice brevicalyx by using HPLC/HRMS and HPLC-DAD/ESI-MS(n). The results of the present study can assist in on-line structural identification of analogous constituents and targeted isolation of novel compounds from crude plant extracts.
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Simultaneous determination of all polyphenols in vegetables, fruits, and teas.
Sakakibara, Hiroyuki; Honda, Yoshinori; Nakagawa, Satoshi; Ashida, Hitoshi; Kanazawa, Kazuki
2003-01-29
Polyphenols, which have beneficial effects on health and occur ubiquitously in plant foods, are extremely diverse. We developed a method for simultaneously determining all the polyphenols in foodstuffs, using HPLC and a photodiode array to construct a library comprising retention times, spectra of aglycons, and respective calibration curves for 100 standard chemicals. The food was homogenized in liquid nitrogen, lyophilized, extracted with 90% methanol, and subjected to HPLC without hydrolysis. The recovery was 68-92%, and the variation in reproducibility ranged between 1 and 9%. The HPLC eluted polyphenols with good resolution within 95 min in the following order: simple polyphenols, catechins, anthocyanins, glycosides of flavones, flavonols, isoflavones and flavanones, their aglycons, anthraquinones, chalcones, and theaflavins. All the polyphenols in 63 vegetables, fruits, and teas were then examined in terms of content and class. The present method offers accuracy by avoiding the decomposition of polyphenols during hydrolysis, the ability to determine aglycons separately from glycosides, and information on simple polyphenol levels simultaneously.
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Tuominen, Anu; Salminen, Juha-Pekka
2017-08-09
The seasonal variation of polyphenols in the aboveground organs and roots of Geranium sylvaticum in four populations was studied using UPLC-DAD-ESI-QqQ-MS/MS. The content of the main compound, geraniin, was highest (16% of dry weight) in the basal leaves after the flowering period but stayed rather constant throughout the growing season. Compound-specific mass spectrometric methods revealed the different seasonal patterns in minor polyphenols. Maximum contents of galloylglucoses and flavonol glycosides were detected in the small leaves in May, whereas the contents of further modified ellagitannins, such as ascorgeraniin and chebulagic acid, increased during the growing season. In flower organs, the polyphenol contents differed significantly between ontogenic phases so that maximum amounts were typically found in the bud phase, except in pistils the amount of gallotannins increased significantly in the fruit phase. These results can be used in evaluating the role of polyphenols in plant-herbivore interactions or in planning the best collection times of G. sylvaticum for compound isolation purposes.
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Antunes-Ricardo, Marilena; Rodríguez-Rodríguez, César; Gutiérrez-Uribe, Janet A; Cepeda-Cañedo, Eduardo; Serna-Saldívar, Sergio O
2017-08-22
Isorhamnetin glycosides are representative compounds of Opuntia ficus-indica that possess different biological activities. There is slight information about the changes in bioaccessibility induced by the glycosylation pattern of flavonoids, particularly for isorhamnetin. In this study, the bioaccessibility and permeability of isorhamnetin glycosides extracted from O. ficus-indica were contrasted with an isorhamnetin standard. Also, the plasma stability of these isorhamnetin glycosides after intravenous administration in rats was evaluated. Recoveries of isorhamnetin after oral and gastric digestion were lower than that observed for its glycosides. After intestinal digestion, isorhamnetin glycosides recoveries were reduced to less than 81.0%. The apparent permeability coefficient from apical (AP) to basolateral (BL) direction (Papp (AP-BL) ) of isorhamnetin was 2.6 to 4.6-fold higher than those obtained for its glycosides. Isorhamnetin diglycosides showed higher Papp (AP-BL) values than triglycosides. Sugar substituents affected the Papp (AP-BL) of the triglycosides. Isorhamnetin glycosides were better retained in the circulatory system than the aglycone. After intravenous dose of the isorhamnetin standard, the elimination half-life was 0.64 h but increased to 1.08 h when the O. ficus-indica extract was administered. These results suggest that isorhamnetin glycosides naturally found in O. ficus-indica could be a controlled delivery system to maintain a constant plasmatic concentration of this important flavonoid to exert its biological effects in vivo.
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New Knowledge About Old Drugs: The Anti-Inflammatory Properties of Cardiac Glycosides.
Fürst, Robert; Zündorf, Ilse; Dingermann, Theo
2017-08-01
In the 19th century, cardio-active steroid glycosides, shortly cardiac glycosides, were scientifically established as drugs against heart failure. Their in vivo , cellular, and molecular actions as well as their predominant target, Na + -K + -ATPase, have been comprehensively investigated in the 20th century and the discovery of endogenous cardiac glycosides has fostered this research field. In the last years, however, results from clinical trials and meta-analyses have questioned their therapeutic value due to efficacy and safety issues. This has led to a considerable decline of their usage. Beyond the cardiovascular system, cardiac glycosides have been increasingly recognized as antitumor compounds and Na + -K + -ATPase has evolved into a promising drug target in oncology. A wealth of review articles exists that intensively discuss these topics. Surprisingly, the anti-inflammatory actions of cardiac glycosides, which were discovered in the 1960s, have so far hardly been perceived and have not yet been summarized. This review provides an overview of the in vivo and in vitro actions of cardiac glycosides on inflammatory processes and of the signaling mechanisms responsible for these effects: cardiac glycosides have been found to decrease inflammatory symptoms in different animal models of acute and chronic inflammation. Regarding the underlying mechanisms most research has focused on leukocytes. In these cells, cardiac glycosides primarily inhibit cell proliferation and the secretion of proinflammatory cytokines. Georg Thieme Verlag KG Stuttgart · New York.
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Antunes-Ricardo, Marilena; Rodríguez-Rodríguez, César; Cepeda-Cañedo, Eduardo
2017-01-01
Isorhamnetin glycosides are representative compounds of Opuntia ficus-indica that possess different biological activities. There is slight information about the changes in bioaccessibility induced by the glycosylation pattern of flavonoids, particularly for isorhamnetin. In this study, the bioaccessibility and permeability of isorhamnetin glycosides extracted from O. ficus-indica were contrasted with an isorhamnetin standard. Also, the plasma stability of these isorhamnetin glycosides after intravenous administration in rats was evaluated. Recoveries of isorhamnetin after oral and gastric digestion were lower than that observed for its glycosides. After intestinal digestion, isorhamnetin glycosides recoveries were reduced to less than 81.0%. The apparent permeability coefficient from apical (AP) to basolateral (BL) direction (Papp(AP-BL)) of isorhamnetin was 2.6 to 4.6-fold higher than those obtained for its glycosides. Isorhamnetin diglycosides showed higher Papp(AP-BL) values than triglycosides. Sugar substituents affected the Papp(AP-BL) of the triglycosides. Isorhamnetin glycosides were better retained in the circulatory system than the aglycone. After intravenous dose of the isorhamnetin standard, the elimination half-life was 0.64 h but increased to 1.08 h when the O. ficus-indica extract was administered. These results suggest that isorhamnetin glycosides naturally found in O. ficus-indica could be a controlled delivery system to maintain a constant plasmatic concentration of this important flavonoid to exert its biological effects in vivo. PMID:28829356
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Neolignan and flavonoid glycosides in Juniperus communis var. depressa.
Nakanishi, Tsutomu; Iida, Naoki; Inatomi, Yuka; Murata, Hiroko; Inada, Akira; Murata, Jin; Lang, Frank A; Iinuma, Munekazu; Tanaka, Toshiyuki
2004-01-01
Two neolignan glycosides (junipercomnosides A and B) were isolated from aerial parts of Juniperus communis var. depressa along with two known neolignan glycosides and seven flavonoid glycosides. The structures of the isolated compounds were determined by spectral analysis, in particular by 2D-NMR analysis. The significance of distribution of flavonoids in the chemotaxonomy of genus Juniperus was also discussed.
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Prata, Cecilia; Zambonin, Laura; Rizzo, Benedetta; Vieceli Dalla Sega, Francesco
2017-01-01
Stevia rebaudiana Bertoni is a shrub having a high content of sweet diterpenoid glycosides in its leaves, mainly stevioside and rebaudioside A, which are used as noncaloric, natural sweeteners. The aim of this study was to deepen the knowledge about the insulin-mimetic effect exerted by four different mixtures of steviol glycosides, rich in stevioside and rebaudioside A, in neonatal rat cardiac fibroblasts. The potential antioxidant activity of these steviol glycosides was also assessed, as oxidative stress is associated with diabetes. Likewise the insulin effect, steviol glycosides caused an increase in glucose uptake into rat fibroblasts by activating the PI3K/Akt pathway, thus inducing Glut4 translocation to the plasma membrane. The presence of S961, an insulin antagonist, completely abolished these effects, allowing to hypothesize that steviol glycosides could act as ligands of the same receptor engaged by insulin. Moreover, steviol glycosides counteracted oxidative stress by increasing reduced glutathione intracellular levels and upregulating expression and activity of the two antioxidant enzymes superoxide dismutase and catalase. The present work unravels the insulin-mimetic effect and the antioxidant property exerted by steviol glycosides, suggesting their potential beneficial role in the cotreatment of diabetes and in health maintenance. PMID:28947927
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[Plants as a source of natural harmful substances].
Czerwiecki, Ludwik
2005-01-01
In this review the several data concerning phytotoxins as natural harmful substances of plants and phycotoxins--toxicants of algae were described. For example plants are source of pyrrolizidine alkaloids, glycoalkaloids, glucosinolates as well as glycosides, saponine and psolarens. Possible adverse effects of phytoestrogens as endocrine disruptors versus beneficial influence these substances on human organism were mentioned. About lectins as possible factors of some diseases was reported, as well as some proteins as allergens of soy and peanuts was mentioned. Accumulated by shellfish and fish the most important phycotoxins such as saxitoxin, okadaic acid, brevetoxins and ciguatoxins were described. Phycotoxins produced several poisoning symptoms. Microcystins and nodularin--cyanobacterial phycotoxins of freshwater, was mentioned. In conclusion, the need of limitation of permissible levels of some plant toxicants, development of analytical methods as well as knowledge of influence of some technological processes on toxic plant substances was highlighted. The importance of balanced diet as a tool of defense against plant toxicants was concluded.
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The contribution of wine-derived monoterpene glycosides to retronasal odour during tasting.
Parker, Mango; Black, Cory A; Barker, Alice; Pearson, Wes; Hayasaka, Yoji; Francis, I Leigh
2017-10-01
This study investigated the sensory significance of monoterpene glycosides during tasting, by retronasal perception of odorant aglycones released in-mouth. Monoterpene glycosides were isolated from Gewürztraminer and Riesling juices and wines, chemically characterised and studied using sensory time-intensity methodology, together with a synthesised monoterpene glucoside. When assessed in model wine at five times wine-like concentration, Gewürztraminer glycosides and geranyl glucoside gave significant fruity flavour, although at wine-like concentrations, or in the presence of wine volatiles, the effect was not significant. Gewürztraminer glycosides, geranyl glucoside and guaiacyl glucoside were investigated using a sensory panel (n=39), revealing large inter-individual variability, with 77% of panellists responding to at least one glycoside. The study showed for the first time that grape-derived glycosides can contribute perceptible fruity flavour, providing a means of enhancing flavour in wines, and confirms the results of previous studies that the effect is highly variable across individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Chyrek, R; Jabłecka, A; Pupek-Musialik, D; Lowicki, Z
2000-08-01
67 year old patient with chronic heart failure and persistent atrial fibrillation had overdosed glycosides for several months. The symptoms of gastrointestinal system and nervous system appeared after long term therapy with toxic doses of glycosides. Originally depression was diagnosed based on the central nervous system disturbances. Even though overdose of glycosides was diagnosed the blood serum glycoside level was within the therapeutic limits. Based on the precise analysis of the data, it was concluded that the reason for normal blood serum glycoside level in this case was coexisting hyperthyreosis.
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An Industrial Chemistry Course that Optimizes the Value of Plant Tours
ERIC Educational Resources Information Center
Hartman, J. Stephen
2005-01-01
Plant tours, when emphasized appropriately and fully integrated into an industrial chemistry course, are very useful in motivating students and deepening their understanding of the chemical industry. Emphasis is placed on plant tours as it adds immediacy and a practical flavor to the course and is a good preparation for the graduates who move from…
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Neugart, Susanne; Krumbein, Angelika; Zrenner, Rita
2016-01-01
Light intensity and temperature are very important signals for the regulation of plant growth and development. Plants subjected to less favorable light or temperature conditions often respond with accumulation of secondary metabolites. Some of these metabolites have been identified as bioactive compounds, considered to exert positive effects on human health when consumed regularly. In order to test a typical range of growth parameters for the winter crop Brassica oleracea var. sabellica, plants were grown either at 400 μmol m(-2) s(-1) or 100 μmol m(-2) s(-1) at 10°C, or at 400 μmol m(-2) s(-1) with 5 or 15°C. The higher light intensity overall increased flavonol content of leaves, favoring the main quercetin glycosides, a caffeic acid monoacylated kaempferol triglycoside, and disinapoyl-gentiobiose. The higher temperature mainly increased the hydroxycinnamic acid derivative disinapoyl-gentiobiose, while at lower temperature synthesis is in favor of very complex sinapic acid acylated flavonol tetraglycosides such as kaempferol-3-O-sinapoyl-sophoroside-7-O-diglucoside. A global analysis of light and temperature dependent alterations of gene expression in B. oleracea var. sabellica leaves was performed with the most comprehensive Brassica microarray. When compared to the light experiment much less genes were differentially expressed in kale leaves grown at 5 or 15°C. A structured evaluation of differentially expressed genes revealed the expected enrichment in the functional categories of e.g. protein degradation at different light intensities or phytohormone metabolism at different temperature. Genes of the secondary metabolism namely phenylpropanoids are significantly enriched with both treatments. Thus, the genome of B. oleracea was screened for predicted genes putatively involved in the biosynthesis of flavonoids and hydroxycinnamic acid derivatives. All identified B. oleracea genes were analyzed for their most specific 60-mer oligonucleotides present on the 2 × 105 K format Brassica microarray. Expression differences were correlated to the structure-dependent response of flavonoid glycosides and hydroxycinnamic acid derivatives to alterations in either light or temperature. The altered metabolite accumulation was mainly reflected on gene expression level of core biosynthetic pathway genes and gave further hints to an isoform specific functional specialization.
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Neugart, Susanne; Krumbein, Angelika; Zrenner, Rita
2016-01-01
Light intensity and temperature are very important signals for the regulation of plant growth and development. Plants subjected to less favorable light or temperature conditions often respond with accumulation of secondary metabolites. Some of these metabolites have been identified as bioactive compounds, considered to exert positive effects on human health when consumed regularly. In order to test a typical range of growth parameters for the winter crop Brassica oleracea var. sabellica, plants were grown either at 400 μmol m−2 s−1 or 100 μmol m−2 s−1 at 10°C, or at 400 μmol m−2 s−1 with 5 or 15°C. The higher light intensity overall increased flavonol content of leaves, favoring the main quercetin glycosides, a caffeic acid monoacylated kaempferol triglycoside, and disinapoyl-gentiobiose. The higher temperature mainly increased the hydroxycinnamic acid derivative disinapoyl-gentiobiose, while at lower temperature synthesis is in favor of very complex sinapic acid acylated flavonol tetraglycosides such as kaempferol-3-O-sinapoyl-sophoroside-7-O-diglucoside. A global analysis of light and temperature dependent alterations of gene expression in B. oleracea var. sabellica leaves was performed with the most comprehensive Brassica microarray. When compared to the light experiment much less genes were differentially expressed in kale leaves grown at 5 or 15°C. A structured evaluation of differentially expressed genes revealed the expected enrichment in the functional categories of e.g. protein degradation at different light intensities or phytohormone metabolism at different temperature. Genes of the secondary metabolism namely phenylpropanoids are significantly enriched with both treatments. Thus, the genome of B. oleracea was screened for predicted genes putatively involved in the biosynthesis of flavonoids and hydroxycinnamic acid derivatives. All identified B. oleracea genes were analyzed for their most specific 60-mer oligonucleotides present on the 2 × 105 K format Brassica microarray. Expression differences were correlated to the structure-dependent response of flavonoid glycosides and hydroxycinnamic acid derivatives to alterations in either light or temperature. The altered metabolite accumulation was mainly reflected on gene expression level of core biosynthetic pathway genes and gave further hints to an isoform specific functional specialization. PMID:27066016
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NASA Astrophysics Data System (ADS)
Yegoshina, O. V.; Voronov, V. N.; Yarovoy, V. O.; Bolshakova, N. A.
2017-11-01
There are many problems in domestic energy at the present that require urgent solutions in the near future. One of these problems - the aging of the main and auxiliary equipment. Wear of equipment is the cause of decrease reliability and efficiency of power plants. Reliability of the equipment are associated with the introduction of cycle chemistry monitoring system. The most damageable equipment’s are boilers (52.2 %), turbines (12.6 %) and heating systems (12.3 %) according to the review of failure rate on the power plants. The most part of the damageability of the boiler is heated surfaces (73.2 %). According to the Russian technical requirements, the monitoring systems are responsible to reduce damageability the boiler heating surfaces and to increase the reliability of the equipment. All power units capacity of over 50 MW are equipped with cycle chemistry monitoring systems in order to maintain water chemistry within operating limits. The main idea of cycle chemistry monitoring systems is to improve water chemistry at power plants. According to the guidelines, cycle chemistry monitoring systems of a single unit depends on its type (drum or once-through boiler) and consists of: 20…50 parameters of on-line chemical analyzers; 20…30 «grab» sample analyses (daily) and about 15…20 on-line monitored operating parameters. The operator of modern power plant uses with many data at different points of steam/water cycle. Operators do not can estimate quality of the cycle chemistry due to the large volume of daily and every shift information and dispersion of data, lack of systematization. In this paper, an algorithm for calculating the quality index developed for improving control the water chemistry of the condensate, feed water and prevent scaling and corrosion in the steam/water cycle.
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Alpinia calcarata Roscoe: A potential phytopharmacological source of natural medicine
Rahman, Md Atiar; Islam, Md Shahidul
2015-01-01
Alpinia calcarata Roscoe (Family: Zingiberaceae), is a rhizomatous perennial herb, which is commonly used in the traditional medicinal systems in Sri Lanka. Alpinia calcarata is cultivated in tropical countries, including Sri Lanka, India, and Malaysia. Experimentally, rhizomes of Alpinia calcarata are shown to possess antibacterial, antifungal, anthelmintic, antinociceptive, anti-inflammatory, antioxidant, aphrodisiac, gastroprotective, and antidiabetic activities. Phytochemical screening revealed the presence of polyphenols, tannins, flavonoids, steroid glycosides and alkaloids in the extract and essential oil of this plant. Essential oil and extracts from this plant have been found to possess wide range of pharmacological and biological activities. This article provides a comprehensive review of its ethnomedical uses, chemical constituents and the pharmacological profile as a medicinal plant. Particular attention has been given to the pharmacological effects of the essential oil of Alpinia calcarata in this review so that the potential use of this plant either in pharmaceutics or as an agricultural resource can be evaluated. PMID:26009694
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Rainha, Nuno; Koci, Kamila; Coelho, Ana Varela; Lima, Elisabete; Baptista, José; Fernandes-Ferreira, Manuel
2013-02-01
LC-UV and LC-MS analysis were used to study the phenolic composition of water extracts of Hypericum undulatum (HU) shoot cultures and wild-growing (WG) plants. Total phenolic content (TPC), determined using the Folin-Ciocalteu assay, and the antioxidant activity measured by two complementary methods were also performed for each sample. Mass spectrometry revealed several phenolics acids with quinic acid moieties, flavonols, mostly quercetin, luteolin and apigenin glycosides, flavan-3-ols (catechin and epicatechin) and the xanthonoid mangiferin. Differences in phenolic composition profile and TPC were found between the samples. The major phenolic in HU culture-growing (CG) samples is chlorogenic acid, followed by epicatechin, quercitrin and isoquercitrin. The WG plants presents hyperoside as the main phenolic, followed by isoquercitrin, chlorogenic acid and quercetin. The TPC and antioxidant activity were higher in samples from WG plants. Copyright © 2012 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Chiantore, Oscar; Riedo, Chiara; Scalarone, Dominique
2009-07-01
Plant gums are complex polysaccharides used in the field of cultural heritage especially as binding media. Classification of polysaccharides may be achieved on the basis of monosaccharides composition after cleavage of glycosidic bond. Characterization of plant gums in works of art is complicated by the necessity of to use a method minimally invasive and requiring a small mount of sample. Pyrolisys is an useful method to obtain polysaccharides decomposition and generally pyrolysis products can be identified by the use of gas chromatography-mass spectrometry. This paper describes a method where two plant gums, arabic and tragacanth, were pyrolized in presence of silylating agents (HMDS e BSTFA alone and with TMCS as catalyst) using an on-line Py-GC/MS apparatus. Some characteristic trimethylsilyl derivatives of monosaccharides were identified on the basis of mass spectra. The presence of characteristic pyrolysis products of sugars allows to distinguish the two gums.
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Guleria, Praveen; Yadav, Sudesh Kumar
2013-01-01
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
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Zimmerman, Duane R; Koszewski, Nicholas J; Hoy, Derrel A; Goff, Jesse P; Horst, Ronald L
2015-04-01
Leaves of the Solanum glaucophyllum (Sg) plant, indigenous to South America, have long been known for their calcinogenic toxicity in ruminant animals. It was determined the leaves contained glycosidic derivatives of 1,25-dihydroxyvitamin D3 (1,25D3) and liberation of the free hormone by rumen bacterial populations elicited a hypercalcemic response. Our interest in the leaves is predicated on the concept that the glycoside forms of 1,25D3 would target release of the active hormone in the lower gut of non-ruminant mammals. This would provide a means of delivering 1,25D3 directly to the colon, where the hormone has been shown to have beneficial effects in models of inflammatory bowel disease (IBD) and colon cancer. We fed mice for 10 days with variable amounts of Sg leaf. Feeding 7-333μg leaf/day produced no changes in plasma Ca(2+) and 1,25D3 concentrations, and only at ≥1000μg leaf/day did these values become significantly elevated compared to controls. Gene expression studies from colon tissue indicated a linear relationship between the amount of leaf consumed and expression of the Cyp24a1 gene. In contrast, Cyp24a1 gene expression in the duodenums and ileums of these mice was unchanged compared to controls. One of the major 1,25D3-glycosides was isolated from leaves following extraction and purification by Sep-Pak cartridges and HPLC fractionation. Ultraviolet absorbance was consistent with modification of the 1-hydroxyl group, and positive ion ESI mass spectrometry indicated a diglycoside of 1,25D3. 2-Dimensional NMR analyses were carried out and established the C1 proton of the A-ring was interacting with a C1' sugar proton, while the C3 proton of the A-ring was linked with a second C1' sugar proton. The structure of the isolated compound is therefore consistent with a β-linked 1,3-diglycoside of 1,25D3. Thus, Sg leaf administered to mice at up to 333 ug/day can elicit colon-specific enhancement of Cyp24a1 gene expression without inducing hypercalcemia, and the 1,3-diglycoside is one of the major forms of 1,25D3 found in the leaf. This article is part of a Special Issue entitled '17th Vitamin D Workshop'. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Ahmed, Firoj; Toume, Kazufumi; Ohtsuki, Takashi; Rahman, Mahmudur; Sadhu, Samir Kumar; Ishibashi, Masami
2011-01-01
Bioassay guided separation of Sida acuta whole plants led to the isolation of an alkaloid, cryptolepine (1), along with two kaempferol glycosides (2-3). Compound 1 showed strong activity in overcoming TRAIL-resistance in human gastric adenocarcinoma (AGS) cells at 1.25, 2.5 and 5 μm. Combined treatment of 1 and TRAIL sensitized AGS cells to TRAIL-induced apoptosis at the aforementioned concentrations. Copyright © 2010 John Wiley & Sons, Ltd.
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Gao, Wen; Chen, Chao; Kong, De-Yun
2013-01-01
Four new flavonol glycosides (1-4), hippophins C-F, together with one known flavonoid (5), were isolated from the seed residue of Hippophae rhamnoides subsp. sinensis. The chemical structures of these compounds were characterized by 1D and 2D NMR, and HR-ESI-MS data. This report is a continuous research work on the systematic chemical investigation of plants of the genus Hippophae in our laboratory.
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Ricigliano, Vincent A; Fitz, William; Copeland, Duan C; Mott, Brendon M; Maes, Patrick; Floyd, Amy S; Dockstader, Arnold; Anderson, Kirk E
2017-10-01
Carbohydrate-active enzymes play an important role in the honey bee (Apis mellifera) due to its dietary specialization on plant-based nutrition. Secretory glycoside hydrolases (GHs) produced in worker head glands aid in the processing of floral nectar into honey and are expressed in accordance with age-based division of labor. Pollen utilization by the honey bee has been investigated in considerable detail, but little is known about the metabolic fate of indigestible carbohydrates and glycosides in pollen biomass. Here, we demonstrate that pollen consumption stimulates the hydrolysis of sugars that are toxic to the bee (xylose, arabinose, mannose). GHs produced in the head accumulate in the midgut and persist in the hindgut that harbors a core microbial community composed of approximately 10 8 bacterial cells. Pollen consumption significantly impacted total and specific bacterial abundance in the digestive tract. Bacterial isolates representing major fermentative gut phylotypes exhibited primarily membrane-bound GH activities that may function in tandem with soluble host enzymes retained in the hindgut. Additionally, we found that plant-originating β-galactosidase activity in pollen may be sufficient, in some cases, for probable physiological activity in the gut. These findings emphasize the potential relative contributions of host, bacteria, and pollen enzyme activities to carbohydrate breakdown, which may be tied to gut microbiome dynamics and associated host nutrition. © 2017 Wiley Periodicals, Inc.
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New insights into plant glycoside hydrolase family 32 in Agave species
Avila de Dios, Emmanuel; Gomez Vargas, Alan D.; Damián Santos, Maura L.; Simpson, June
2015-01-01
In order to optimize the use of agaves for commercial applications, an understanding of fructan metabolism in these species at the molecular and genetic level is essential. Based on transcriptome data, this report describes the identification and molecular characterization of cDNAs and deduced amino acid sequences for genes encoding fructosyltransferases, invertases and fructan exohydrolases (FEH) (enzymes belonging to plant glycoside hydrolase family 32) from four different agave species (A. tequilana, A. deserti, A. victoriae-reginae, and A. striata). Conserved amino acid sequences and a hypervariable domain allowed classification of distinct isoforms for each enzyme type. Notably however neither 1-FFT nor 6-SFT encoding cDNAs were identified. In silico analysis revealed that distinct isoforms for certain enzymes found in a single species, showed different levels and tissue specific patterns of expression whereas in other cases expression patterns were conserved both within the species and between different species. Relatively high levels of in silico expression for specific isoforms of both invertases and fructosyltransferases were observed in floral tissues in comparison to vegetative tissues such as leaves and stems and this pattern was confirmed by Quantitative Real Time PCR using RNA obtained from floral and leaf tissue of A. tequilana. Thin layer chromatography confirmed the presence of fructans with degree of polymerization (DP) greater than DP three in both immature buds and fully opened flowers also obtained from A. tequilana. PMID:26300895
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New insights into plant glycoside hydrolase family 32 in Agave species.
Avila de Dios, Emmanuel; Gomez Vargas, Alan D; Damián Santos, Maura L; Simpson, June
2015-01-01
In order to optimize the use of agaves for commercial applications, an understanding of fructan metabolism in these species at the molecular and genetic level is essential. Based on transcriptome data, this report describes the identification and molecular characterization of cDNAs and deduced amino acid sequences for genes encoding fructosyltransferases, invertases and fructan exohydrolases (FEH) (enzymes belonging to plant glycoside hydrolase family 32) from four different agave species (A. tequilana, A. deserti, A. victoriae-reginae, and A. striata). Conserved amino acid sequences and a hypervariable domain allowed classification of distinct isoforms for each enzyme type. Notably however neither 1-FFT nor 6-SFT encoding cDNAs were identified. In silico analysis revealed that distinct isoforms for certain enzymes found in a single species, showed different levels and tissue specific patterns of expression whereas in other cases expression patterns were conserved both within the species and between different species. Relatively high levels of in silico expression for specific isoforms of both invertases and fructosyltransferases were observed in floral tissues in comparison to vegetative tissues such as leaves and stems and this pattern was confirmed by Quantitative Real Time PCR using RNA obtained from floral and leaf tissue of A. tequilana. Thin layer chromatography confirmed the presence of fructans with degree of polymerization (DP) greater than DP three in both immature buds and fully opened flowers also obtained from A. tequilana.
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Phytochemical screening and quantification of flavonoids from leaf extract of Jatropha curcas Linn.
Ebuehi, O A T; Okorie, N A
2009-01-01
The Jatropha curcas L. (Euphorbiaceae) herb is found in SouthWest, Nigeria and other parts of West Africa, and is claimed to possess anti-hypertensive property. The phytochemical screening and flavonoid quantification of the leaf extract of Jatropha curcas Linn were studied. The phytochemical screening of the methanolic leaf extract of J. curcas L. was carried using acceptable and standard methods. The flavonoid contents of the leaf extract of Jatropha curcas L. were determined using thin layer chromatography (TLC), infrared spectroscopy (IRS) and a reversed phase high performance liquid chromatography (HPLC). The phytochemical screening of the methanolic extract of the leaves of the plant shows the presence of alkaloids, cardiac glycosides, cyanogenic glycosides, phlobatannins, tannins, flavonoids and saponins. To quantify the flavonoid contents of leaf extract of Jatropha curcas L, extracts from the plant samples where examined in a C-18 column with UV detection and isocratic elution with acetonitrile; water (45:55). Levels of flavonoids (flavones) in leaves ranged from 6:90 to 8:85 mg/g dry weight. Results indicate that the methanolic extract of the leaves of Jatropha curcas L. contains useful active ingredients which may serve as potential drug for the treatment of diseases. In addition, a combination of TLC, IRS and HPLC can be used to analyse and quantify the flavonoids present in the leaves of Jatropha curcas L.
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Chemical analysis of bioactive substances in seven siberian Saussurea species
NASA Astrophysics Data System (ADS)
Avdeeva, Elena; Reshetov, Yaroslav; Shurupova, Margarita; Zibareva, Larisa; Borisova, Evgeniia; Belousov, Mikhail
2017-11-01
Main groups of biologically active substances of seven siberian Saussurea species (S. controversa DC., S. latifolia Ledeb., S. parviflora (Poir.) DC., S. frolowii Ledeb, S. amara (L.) DC., S. salicifolia (L.) DC. and S. daurica Adams) have been studied using paper, thin-layer, performance liquid chromatography, IR spectroscopy, spectrophotometry and mass spectrometry with inductively coupled plasma. Siberian Saussurea species have a rich elemental composition and contain a variety of phenolic compounds, amino acids, polysaccharides. The majority of polysaccharides are accumulated by S. controversa, S. salicifolia and S. frolowii. These plants contain a significant amount of calcium that may be a species characteristic. All plants contain quercetin and its glycosides, in some species luteolin, kaempferol, glycosides of apigenin and myricetin were revealed. Phenolic acids with predominant content of caffeic, chlorogenic and cinnamic acids were found in all the species. The maximum amount of phenolic acids and flavonoids was determined in the grass of S. latifolia, S. controversa and S. daurica. Characteristic absorption bands of lactone carbonyl of sesquiterpenoids in IR spectrum found in S. latifolia, S. controversa, S. daurica, S. amara and S. salicifolia. HPLC / UV analysis showed that peaks with absorption maxima of 242-246 nm due to the presence of α,β-unsaturated ketone group in the structure of ecdysteroids were found in S. salicifolia, S. controversa, S. daurica and S. latifolia.
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de Souza Figueiredo, Fabiana; Celano, Rita; de Sousa Silva, Danila; das Neves Costa, Fernanda; Hewitson, Peter; Ignatova, Svetlana; Piccinelli, Anna Lisa; Rastrelli, Luca; Guimarães Leitão, Suzana; Guimarães Leitão, Gilda
2017-01-20
Ampelozizyphus amazonicus Ducke (Rhamnaceae), a medicinal plant used to prevent malaria, is a climbing shrub, native to the Amazonian region, with jujubogenin glycoside saponins as main compounds. The crude extract of this plant is too complex for any kind of structural identification, and HPLC separation was not sufficient to resolve this issue. Therefore, the aim of this work was to obtain saponin enriched fractions from the bark ethanol extract by countercurrent chromatography (CCC) for further isolation and identification/characterisation of the major saponins by HPLC and MS. The butanol extract was fractionated by CCC with hexane - ethyl acetate - butanol - ethanol - water (1:6:1:1:6; v/v) solvent system yielding 4 group fractions. The collected fractions were analysed by UHPLC-HRMS (ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry) and MS n . Group 1 presented mainly oleane type saponins, and group 3 showed mainly jujubogenin glycosides, keto-dammarane type triterpene saponins and saponins with C 31 skeleton. Thus, CCC separated saponins from the butanol-rich extract by skeleton type. A further purification of group 3 by CCC (ethyl acetate - ethanol - water (1:0.2:1; v/v)) and HPLC-RI was performed in order to obtain these unusual aglycones in pure form. Copyright © 2016 Elsevier B.V. All rights reserved.
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Falcão, Soraia I; Vale, Nuno; Gomes, Paula; Domingues, Maria R M; Freire, Cristina; Cardoso, Susana M; Vilas-Boas, Miguel
2013-01-01
Propolis is a chemically complex resinous substance collected by honeybees (Apis mellifera) from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. Its chemical composition depends strongly on the plant sources available around the beehive, which have a direct impact in the quality and bioactivity of the propolis. Being as Portugal is a country of botanical diversity, the phenolic characterisation of propolis from the different regions is a priority. Extensive characterisation of the phenolic composition of Portuguese propolis from different continental regions and islands. Forty propolis ethanolic extracts were analysed extensively by liquid chromatography with diode-array detection coupled to electrospray ionisation tandem mass spectrometry (LC-DAD-ESI-MS(n) ). Seventy-six polyphenols were detected in the samples and two groups of propolis were established: the common temperate propolis, which contained the typical poplar phenolic compounds such as flavonoids and their methylated/esterified forms, phenylpropanoid acids and their esters, and an uncommon propolis type with an unusual composition in quercetin and kaempferol glycosides - some of them never described in propolis. The method allowed the establishment of the phenolic profile of Portuguese propolis from different geographical locations, and the possibility to use some phenolic compounds, such as kaempferol-dimethylether, as geographical markers. Data suggest that other botanical species in addition to poplar trees can be important sources of resins for Portuguese propolis. Copyright © 2012 John Wiley & Sons, Ltd.
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Fatal cardiac glycoside poisoning due to mistaking foxglove for comfrey.
Wu, I-Lin; Yu, Jiun-Hao; Lin, Chih-Chuan; Seak, Chen-June; Olson, Kent R; Chen, Hsien-Yi
2017-08-01
Accidental ingestion of foxglove (Digitalis purpurea) can cause significant cardiac toxicity. We report a patient who ingested foxglove mistaking it for comfrey and developed refractory ventricular arrhythmias. The patient died despite treatment with digoxin-specific antibody fragments (DSFab) and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). A 55-year-old woman presented to the emergency department with nausea, vomiting and generalized weakness eight hours after drinking "comfrey" tea. She had bradycardia (54 beats/min) and hyperkalemia (7.6 mEq/L). Electrocardiogram revealed a first-degree atrioventricular conduction block with premature atrial contractions, followed by polymorphic ventricular tachycardia three hours after arrival. A serum digoxin level was 151.2 ng/mL. The patient developed ventricular fibrillation while waiting for Digibind infusion. Resuscitation was performed and an emergent VA-ECMO was set up. A total of eight vials of Digibind were given over the next 16 hours. She temporarily regained consciousness, but remained hemodynamically unstable and subsequently developed lower limb ischemia and multiple organ failure, and she expired on hospital day seven. A botanist confirmed that the plant was foxglove. The diagnosis of cardiac glycoside plant poisoning can be difficult in the absence of an accurate exposure history. In facilities where DSFab is unavailable or insufficient, early VA-ECMO might be considered in severely cardiotoxic patients unresponsive to conventional therapy.
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Current knowledge of Aronia melanocarpa as a medicinal plant.
Valcheva-Kuzmanova, Stefka V; Belcheva, Anna
2006-01-01
Aronia melanocarpa, native to eastern North America, has become popular in Eastern Europe and Russia. Aronia melanocarpa fruits are one of the richest plant sources of phenolic substances, mainly anthocyanins--glycosides of cyanidin. Anthocyanins are water soluble pigments accounting for the dark blue and even black color of the fruits. Administered orally they can be absorbed as intact glycosides. Aronia melanocarpa fruit juice and anthocyanins derived from the fruits have been studied intensively for the last 15 years. Most of the effects of Aronia melanocarpa anthocyanins are due to their high antioxidative activity. Our investigations have demonstrated a remarkable hepatoprotective, a very good gastroprotective and a pronounced anti-inflammatory effect of Aronia melanocarpa fruit juice in rats as well as a bacteriostatic activity in vitro against Staphylococcus aureus and Escherichia coli and an antiviral activity against type A influenza virus. Research of other authors has demonstrated that Aronia melanocarpa anthocyanins can normalize the carbohydrate metabolism in diabetic patients and in streptozotocin-diabetic rats, have an in vitro antimutagenic activity and exhibit a distinct immunomodulatory activity in human lymphocyte cultures and in patients with breast cancer, suppress the growth of human HT-29 colon cancer cells, inhibit the N-nitrosamine formation in rats and decrease the toxicity and cumulation of cadmium in liver and kidneys. Currently, there are no data in literature about any unwanted and toxic effects of Aronia melanocarpa fruits, juice and extracts.
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Macel, Mirka; de Vos, Ric C H; Jansen, Jeroen J; van der Putten, Wim H; van Dam, Nicole M
2014-07-01
It is often assumed that exotic plants can become invasive when they possess novel secondary chemistry compared with native plants in the introduced range. Using untargeted metabolomic fingerprinting, we compared a broad range of metabolites of six successful exotic plant species and their native congeners of the family Asteraceae. Our results showed that plant chemistry is highly species-specific and diverse among both exotic and native species. Nonetheless, the exotic species had on average a higher total number of metabolites and more species-unique metabolites compared with their native congeners. Herbivory led to an overall increase in metabolites in all plant species. Generalist herbivore performance was lower on most of the exotic species compared with the native species. We conclude that high chemical diversity and large phytochemical uniqueness of the exotic species could be indicative of biological invasion potential.
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Berman, Judit; Sheng, Yanmin; Gómez Gómez, Lourdes; Veiga, Tania; Ni, Xiuzhen; Farré, Gemma; Capell, Teresa; Guitián, Javier; Guitián, Pablo; Sandmann, Gerhard; Christou, Paul; Zhu, Changfu
2016-01-01
Flower color is an important characteristic that determines the commercial value of ornamental plants. Gentian flowers occur in a limited range of colors because this species is not widely cultivated as a cut flower. Gentiana lutea L. var. aurantiaca (abbr, aurantiaca) is characterized by its orange flowers, but the specific pigments responsible for this coloration are unknown. We therefore investigated the carotenoid and flavonoid composition of petals during flower development in the orange-flowered gentian variety of aurantiaca and the yellow-flowered variety of G. lutea L. var. lutea (abbr, lutea). We observed minor varietal differences in the concentration of carotenoids at the early and final stages, but only aurantiaca petals accumulated pelargonidin glycosides, whereas these compounds were not found in lutea petals. We cloned and sequenced the anthocyanin biosynthetic gene fragments from petals, and analyzed the expression of these genes in the petals of both varieties to determine the molecular mechanisms responsible for the differences in petal color. Comparisons of deduced amino acid sequences encoded by the isolated anthocyanin cDNA fragments indicated that chalcone synthase (CHS), chalcone isomerase (CHI), anthocyanidin synthase 1 (ANS1) and ANS2 are identical in both aurantiaca and lutea varieties whereas minor amino acid differences of the deduced flavonone 3-hydroxylase (F3H) and dihydroflavonol 4-reductase (DFR) between both varieties were observed. The aurantiaca petals expressed substantially higher levels of transcripts representing CHS, F3H, DFR, ANS and UDP-glucose:flavonoid-3-O-glucosyltransferase genes, compared to lutea petals. Pelargonidin glycoside synthesis in aurantiaca petals therefore appears to reflect the higher steady-state levels of pelargonidin synthesis transcripts. Moreover, possible changes in the substrate specificity of DFR enzymes may represent additional mechanisms for producing red pelargonidin glycosides in petals of aurantiaca. Our report describing the exclusive accumulation of pelargonidin glycosides in aurantiaca petals may facilitate the modification of gentian flower color by the production of red anthocyanins.
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Patil, Jitendra Gopichand; Ahire, Mahendra Laxman; Nitnaware, Kirti Manik; Panda, Sayantan; Bhatt, Vijay P; Kishor, Polavarapu B Kavi; Nikam, Tukaram Dayaram
2013-03-01
Digitalis purpurea L. (Scrophulariaceae; Foxglove) is a source of cardiotonic glycosides such as digitoxin and digoxin which are commercially applied in the treatment to strengthen cardiac diffusion and to regulate heart rhythm. This investigation deals with in vitro propagation and elicited production of cardiotonic glycosides digitoxin and digoxin in shoot cultures of D. purpurea L. In vitro germinated seedlings were used as a primary source of explants. Multiple shoot formation was achieved for three explant types (nodal, internodal, and leaf) cultured on Murashige and Skoog (MS) medium with several treatments of cytokinins (6-benzyladenine-BA; kinetin-Kin; and thidiazuron-TDZ) and auxins (indole-3-acetic acid-IAA; α-naphthaleneacetic acid-NAA; and 2,4-dichlorophenoxy acetic acid-2,4-D). Maximum multiple shoots (12.7 ± 0.6) were produced from nodal explants on MS + 7.5 μM BA. Shoots were rooted in vitro on MS containing 15 μM IAA. Rooted plantlets were successfully acclimatized. To further maintain the multiple shoot induction, mother tissue was cut into four equal parts and repeatedly sub-cultured on fresh shoot induction liquid medium after each harvest. On adaptation of this strategy, an average of 18 shoots per explant could be produced. This strategy was applied for the production of biomass and glycosides digitoxin and digoxin in shoot cultures on MS medium supplemented with 7.5 μM BA and several treatments with plant growth regulators, incubation period, abiotic (salicylic acid, mannitol, sorbitol, PEG-6000, NaCl, and KCl), biotic (Aspergillus niger, Helminthosporium sp., Alternaria sp., chitin, and yeast extract) elicitors, and precursors (progesterone, cholesterol, and squalene). The treatment of KCl, mycelial mass of Helminthosporium sp., and progesterone were highly effective for the production of cardenolides. In the presence of progesterone (200 to 300 mg/l), digitoxin and digoxin accumulation was enhanced by 9.1- and 11.9-folds respectively.
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Sun, Wei; Liang, Lingjie; Meng, Xiangyu; Li, Yueqing; Gao, Fengzhan; Liu, Xingxue; Wang, Shucai; Gao, Xiang; Wang, Li
2016-01-01
The glycosylation of flavonoids increases their solubility and stability in plants. Flowers accumulate anthocyanidin and flavonol glycosides which are synthesized by UDP-sugar flavonoid glycosyltransferases (UFGTs). In our previous study, a cDNA clone (Fh3GT1) encoding UFGT was isolated from Freesia hybrida, which was preliminarily proved to be invovled in cyanidin 3-O-glucoside biosynthesis. Here, a variety of anthocyanin and flavonol glycosides were detected in flowers and other tissues of F. hybrida, implying the versatile roles of Fh3GT1 in flavonoids biosynthesis. To further unravel its multi-functional roles, integrative analysis between gene expression and metabolites was investigated. The results showed expression of Fh3GT1 was positively related to the accumulation of anthocyanins and flavonol glycosides, suggesting its potential roles in the biosynthesis of both flavonoid glycosides. Subsequently, biochemical analysis results revealed that a broad range of flavonoid substrates including flavonoid not naturally occurred in F. hybrida could be recognized by the recombinant Fh3GT1. Both UDP-glucose and UDP-galactose could be used as sugar donors by recombinant Fh3GT1, although UDP-galactose was transferred with relatively low activity. Furthermore, regiospecificity analysis demonstrated that Fh3GT1 was able to glycosylate delphinidin at the 3-, 4-′, and 7- positions in a sugar-dependent manner. And the introduction of Fh3GT1 into Arabidopsis UGT78D2 mutant successfully restored the anthocyanins and flavonols phenotypes caused by lost-of-function of the 3GT, indicating that Fh3GT1 functions as a flavonoid 3-O-glucosyltransferase in vivo. In summary, these results demonstrate that Fh3GT1 is a flavonoid 3-O-glycosyltransferase using UDP-glucose as the preferred sugar donor and may involve in flavonoid glycosylation in F. hybrida. PMID:27064818
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Sun, Wei; Liang, Lingjie; Meng, Xiangyu; Li, Yueqing; Gao, Fengzhan; Liu, Xingxue; Wang, Shucai; Gao, Xiang; Wang, Li
2016-01-01
The glycosylation of flavonoids increases their solubility and stability in plants. Flowers accumulate anthocyanidin and flavonol glycosides which are synthesized by UDP-sugar flavonoid glycosyltransferases (UFGTs). In our previous study, a cDNA clone (Fh3GT1) encoding UFGT was isolated from Freesia hybrida, which was preliminarily proved to be invovled in cyanidin 3-O-glucoside biosynthesis. Here, a variety of anthocyanin and flavonol glycosides were detected in flowers and other tissues of F. hybrida, implying the versatile roles of Fh3GT1 in flavonoids biosynthesis. To further unravel its multi-functional roles, integrative analysis between gene expression and metabolites was investigated. The results showed expression of Fh3GT1 was positively related to the accumulation of anthocyanins and flavonol glycosides, suggesting its potential roles in the biosynthesis of both flavonoid glycosides. Subsequently, biochemical analysis results revealed that a broad range of flavonoid substrates including flavonoid not naturally occurred in F. hybrida could be recognized by the recombinant Fh3GT1. Both UDP-glucose and UDP-galactose could be used as sugar donors by recombinant Fh3GT1, although UDP-galactose was transferred with relatively low activity. Furthermore, regiospecificity analysis demonstrated that Fh3GT1 was able to glycosylate delphinidin at the 3-, 4-', and 7- positions in a sugar-dependent manner. And the introduction of Fh3GT1 into Arabidopsis UGT78D2 mutant successfully restored the anthocyanins and flavonols phenotypes caused by lost-of-function of the 3GT, indicating that Fh3GT1 functions as a flavonoid 3-O-glucosyltransferase in vivo. In summary, these results demonstrate that Fh3GT1 is a flavonoid 3-O-glycosyltransferase using UDP-glucose as the preferred sugar donor and may involve in flavonoid glycosylation in F. hybrida.
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Gómez Gómez, Lourdes; Veiga, Tania; Ni, Xiuzhen; Farré, Gemma; Capell, Teresa; Guitián, Javier; Guitián, Pablo; Sandmann, Gerhard; Christou, Paul
2016-01-01
Flower color is an important characteristic that determines the commercial value of ornamental plants. Gentian flowers occur in a limited range of colors because this species is not widely cultivated as a cut flower. Gentiana lutea L. var. aurantiaca (abbr, aurantiaca) is characterized by its orange flowers, but the specific pigments responsible for this coloration are unknown. We therefore investigated the carotenoid and flavonoid composition of petals during flower development in the orange-flowered gentian variety of aurantiaca and the yellow-flowered variety of G. lutea L. var. lutea (abbr, lutea). We observed minor varietal differences in the concentration of carotenoids at the early and final stages, but only aurantiaca petals accumulated pelargonidin glycosides, whereas these compounds were not found in lutea petals. We cloned and sequenced the anthocyanin biosynthetic gene fragments from petals, and analyzed the expression of these genes in the petals of both varieties to determine the molecular mechanisms responsible for the differences in petal color. Comparisons of deduced amino acid sequences encoded by the isolated anthocyanin cDNA fragments indicated that chalcone synthase (CHS), chalcone isomerase (CHI), anthocyanidin synthase 1 (ANS1) and ANS2 are identical in both aurantiaca and lutea varieties whereas minor amino acid differences of the deduced flavonone 3-hydroxylase (F3H) and dihydroflavonol 4-reductase (DFR) between both varieties were observed. The aurantiaca petals expressed substantially higher levels of transcripts representing CHS, F3H, DFR, ANS and UDP-glucose:flavonoid-3-O-glucosyltransferase genes, compared to lutea petals. Pelargonidin glycoside synthesis in aurantiaca petals therefore appears to reflect the higher steady-state levels of pelargonidin synthesis transcripts. Moreover, possible changes in the substrate specificity of DFR enzymes may represent additional mechanisms for producing red pelargonidin glycosides in petals of aurantiaca. Our report describing the exclusive accumulation of pelargonidin glycosides in aurantiaca petals may facilitate the modification of gentian flower color by the production of red anthocyanins. PMID:27589396
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Synthesis and anti-fungal activity of acetylated glycosides of 1,4-naphthoquinone
DOE Office of Scientific and Technical Information (OSTI.GOV)
Polonik, S.G.; Tolkach, A.M.; Uvarova, N.I.
1986-12-01
The authors synthesize a series of glycoside derivatives of 1,4-naphthoquinones (VIII-XXII) and study their anti-fungal activity in a search for more effective preparations for the medical and food industries. The structures of the newly prepared glycosides were verified by IR and /sup 1/H and /sup 13/C NMR spectroscopy. The properties of acetylated 1,4-naphthoquinone glycosides are presented.
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Wu, Jun; Yi, Yang-Hua; Tang, Hai-Feng; Wu, Hou-Ming; Zhou, Zhen-Rong
2007-01-01
Two new triterpene glycosides, hillasides A (1) and B (2), were isolated from the sea cucumber H. hilla Lesson, together with one known glycoside holothuria B (3). Their structures were deduced by extensive spectral analysis and chemical evidences. The presence of conjugated double bonds [22E,24-diene] in the aglycone of 1 is a rare structural feature among sea cucumber glycosides. The two glycosides showed significant cytotoxicity against eight human tumour cell lines (A-549, MCF-7, IA9, CAKI-1, PC-3, KB, KB-VIN and HCT-8) with IC(50) in the range of 0.1-3.8 microg/ml.
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Senica, Mateja; Stampar, Franci; Veberic, Robert; Mikulic-Petkovsek, Maja
2016-07-15
Popular liqueurs made from apricot/cherry pits were evaluated in terms of their phenolic composition and occurrence of cyanogenic glycosides (CGG). Analyses consisted of detailed phenolic and cyanogenic profiles of cherry and apricot seeds as well as beverages prepared from crushed kernels. Phenolic groups and cyanogenic glycosides were analyzed with the aid of high-performance liquid chromatography (HPLC) and mass spectrophotometry (MS). Lower levels of cyanogenic glycosides and phenolics have been quantified in liqueurs compared to fruit kernels. During fruit pits steeping in the alcohol, the phenolics/cyanogenic glycosides ratio increased and at the end of beverage manufacturing process higher levels of total analyzed phenolics were detected compared to cyanogenic glycosides (apricot liqueur: 38.79 μg CGG per ml and 50.57 μg phenolics per ml; cherry liqueur 16.08 μg CGG per ml and 27.73 μg phenolics per ml). Although higher levels of phenolics are characteristic for liqueurs made from apricot and cherry pits these beverages nevertheless contain considerable amounts of cyanogenic glycosides. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Wu, Xinhua; Zhu, Ruizhi; Ren, Zhuoying; Wang, Kai; Mou, Dingrong; Wei, Wanzhi; Miao, Mingming
2009-11-01
A qualitative method for the identification of 5 main glycosidic flavor precursors in tobacco was developed by using ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI MS/MS) and gas chromatography-mass spectrometry (GC-MS). The glycosidic flavor precursors in tobacco were extracted with methanol, cleaned up with an XAD-2 column. The aglycones were later released by enzyme-mediated hydrolysis under the condition of pH 5. The 5 volatile aglycone moieties were identified by GC-MS standard spectra library. The precursor ions of glycosides were determined by using electrospray ionization mass spectrometry in negative ion mode, then the 5 glycosidic flavor precursors were identified by using product ion scan (MS2) finally, using UPLC-ESI MS/MS, separation and identification of 5 glycosidic flavor precursors were accomplished on an RP-C,8 column in the multiple reaction monitoring (MRM) mode by using methanol and acetic acid-ammonium acetate aqueous solution as eluent. This work lays a foundation for the analysis of glycosidic flavor precursors without the standards by using liquid chromatography-mass spectrometry.
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Chelyn, June Lee; Omar, Maizatul Hasyima; Mohd Yousof, Nor Syaidatul Akmal; Ranggasamy, Ramesh; Wasiman, Mohd Isa; Ismail, Zakiah
2014-01-01
Clinacanthus nutans (family Acanthaceae) has been used for the treatment of inflammation and herpes viral infection. Currently, there has not been any report on the qualitative and quantitative determination of the chemical markers in the leaves of C. nutans. The C-glycosidic flavones such as shaftoside, isoorientin, orientin, isovitexin, and vitexin have been found to be major flavonoids in the leaves of this plant. Therefore, we had developed a two-step method using thin-layer chromatography (TLC) and high pressure liquid chromatography (HPLC) for the rapid identification and quantification of the flavones C-glycosides in C. nutans leaves. The TLC separation of the chemical markers was achieved on silica gel 60 plate using ethyl acetate : formic acid : acetic acid : water (100 : 11 : 11 : 27 v/v/v/v) as the mobile phase. HPLC method was optimized and validated for the quantification of shaftoside, orientin, isovitexin, and vitexin and was shown to be linear in concentration range tested (0.4–200 μg/mL, r 2 ≥ 0.996), precise (RSD ≤ 4.54%), and accurate (95–105%). The concentration of shaftoside, orientin, vitexin, and isovitexin in C. nutans leave samples was 2.55–17.43, 0.00–0.86, 0.00–2.01, and 0.00–0.91 mmol/g, respectively. PMID:25405231
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Huyen, Chu Thi Thanh; Luyen, Bui Thi Thuy; Khan, Ghulam Jilany; Oanh, Ha Van; Hung, Ta Manh; Li, Hui-Jun; Li, Ping
2018-05-04
This study was designed to search for novel anti-cancer compounds from natural plants. The 70% ethanolic extract from the rizhomes of Cimicifuga dahurica (Turcz.) Maxim. (Ranunculaceae) was found to possess significant in vitro anti-proliferative effects on MCF-7 breast cancer cells. A phytochemical investigation using assay-guided fractionation of the ethanolic extract of C. dahurica resulted in the isolation of one new phenolic amide glycoside 3 , two new lignan glycosides 4 and 7 , one new 9,19-cycloartane triterpenoid glycoside 6 , and thirteen known constituents 1 , 2 , 5 , and 8 ⁻ 17 . The structures of 3 , 4 , 6 , and 7 were established using contemporary NMR methods and from their HRESIMS data. The anti-proliferative effects of isolated compounds were evaluated using the BrdU-proliferation kit. Five among the 17 isolated compounds showed significant anti-proliferative effects ( p ≤ 0.05), wherein compound 7 showed the most significant anti-proliferative and cell cycle arresting effect ( p ≤ 0.05) which followed a dose dependent manner. Western blot protein expression analysis showed a down expression of c-Myc and cyclin D1 which further elucidated the anti-proliferation mechanism of compound 7 while apoptotic effects were found in association with Bcl-2 family protein expression variations. Conclusively this study reports the isolation and identification of 17 compounds from C. dahurica , including four novel molecules, in addition to the fact that compound 7 possesses significant anti-proliferative and apoptotic effects in vitro that may require further exploration.
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Natural macromolecules with protective and antitumor activity.
Cioanca, Oana; Trifan, Adriana; Mircea, Cornelia; Dragos, Scripcariu; Hancianu, Monica
2018-04-24
This review summarizes the literature data regarding plant lectins and as novel drug sources in prevention or treatment of cancer. Moreover, such compounds have been described as natural toxins that possess different biological activities (cytotoxic, antitumor, antimutagenic and anticarcinogenic properties). This activity depends greatly on their structure and affinity. Most of the mushroom heterosides are known as β-glucans with β-(1→3)-glycosidic bonds. It is thought that their conformation, bonds, molecular size can modulate the immune response by triggering different receptors. The mechanism on normal and tumor cells of various plant and mushroom polysaccharides and lectins is briefly presented in this paper. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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Phenolic glycosides and ionone glycoside from the stem of Sargentodoxa cuneata.
Chang, Jun; Case, Ryan
2005-12-01
Four phenolic glycosides, cuneatasides A-D (1-4), and one ionone glycoside cuneataside E (5), together with seven known phenolic compounds (6-12) were isolated from the water-soluble constituents of the stem of Sargentodoxa cuneata (Sargentodoxaceae). Their structures were elucidated by spectroscopic analysis. In vitro tests for antimicrobial activity showed compounds 1 and 2 to possess significant activity against two Gram-positive organisms, Staphylococcus aureus and Micrococcus epidermidis.
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NASA Astrophysics Data System (ADS)
Tyapkov, V. F.
2014-07-01
The secondary coolant circuit water chemistry with metering amines began to be put in use in Russia in 2005, and all nuclear power plant units equipped with VVER-1000 reactors have been shifted to operate with this water chemistry for the past seven years. Owing to the use of water chemistry with metering amines, the amount of products from corrosion of structural materials entering into the volume of steam generators has been reduced, and the flow-accelerated corrosion rate of pipelines and equipment has been slowed down. The article presents data on conducting water chemistry in nuclear power plant units with VVER-1000 reactors for the secondary coolant system equipment made without using copper-containing alloys. Statistical data are presented on conducting ammonia-morpholine and ammonia-ethanolamine water chemistries in new-generation operating power units with VVER-1000 reactors with an increased level of pH. The values of cooling water leaks in turbine condensers the tube system of which is made of stainless steel or titanium alloy are given.
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Pharmacognostic evaluation of leaf of Cordia macleodii Hook., An ethnomedicinally important plant.
Bhide, Bhargav; Pillai, A P G; Shukla, V J; Acharya, R N
2011-04-01
Plants of ethnomedicinal importance have contributed for the development of many new pharmacologically effective molecules/chemical entities to modern medicine. India, the country having one of the richest biodiversity of its flora in its forest, with numerous tribal inhabitants, is able to contribute a lot from ethnomedicine to the ailing humanity. Cordia macleodii Hook. (Boraginaceae), an ethnomedicinal plant has been highlighted for its wound healing, aphrodisiac and hepatoprotective activities. It is a medium-sized tree, known as Panki/Shikari by the tribals, rarely found in the forests of Orissa, Chhattisgarh and Madhya Pradesh. So far, the plant has been studied neither for its pharmacognostical characters nor for its pharmacological actions except its hepatoprotective activity. Hence, it has been selected for a detailed investigation which includes pharmacognostic study of its leaf to find out the diagnostic characters and preliminary physicochemical analysis. Results of the study will help in identifying the plant pharmacognostically. Presence of alkaloids, glycosides and tannins were found during the study.
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Pharmacognostic evaluation of leaf of Cordia macleodii Hook., An ethnomedicinally important plant
Bhide, Bhargav; Pillai, A. P. G.; Shukla, V. J.; Acharya, R. N.
2011-01-01
Plants of ethnomedicinal importance have contributed for the development of many new pharmacologically effective molecules/chemical entities to modern medicine. India, the country having one of the richest biodiversity of its flora in its forest, with numerous tribal inhabitants, is able to contribute a lot from ethnomedicine to the ailing humanity. Cordia macleodii Hook. (Boraginaceae), an ethnomedicinal plant has been highlighted for its wound healing, aphrodisiac and hepatoprotective activities. It is a medium-sized tree, known as Panki/Shikari by the tribals, rarely found in the forests of Orissa, Chhattisgarh and Madhya Pradesh. So far, the plant has been studied neither for its pharmacognostical characters nor for its pharmacological actions except its hepatoprotective activity. Hence, it has been selected for a detailed investigation which includes pharmacognostic study of its leaf to find out the diagnostic characters and preliminary physicochemical analysis. Results of the study will help in identifying the plant pharmacognostically. Presence of alkaloids, glycosides and tannins were found during the study. PMID:22408312
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New benzophenone and quercetin galloyl glycosides from Psidium guajava L.
Matsuzaki, Keiichi; Ishii, Rie; Kobiyama, Kaori; Kitanaka, Susumu
2010-07-01
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.
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Brooks, Larry M; Kuhlman, Benjamin J; McKesson, Doug W; McCloskey, Leo
2013-01-01
The poor interoperability of anthocyanin glycosides measurements by two pH differential methods is documented. Adams-Harbertson, which was proposed for commercial winemaking, was compared to AOAC Official Method 2005.02 for wine. California bottled wines (Pinot Noir, Merlot, and Cabernet Sauvignon) were assayed in a collaborative study (n=105), which found mean precision of Adams-Harbertson winery versus reference measurements to be 77 +/- 20%. Maximum error is expected to be 48% for Pinot Noir, 42% for Merlot, and 34% for Cabernet Sauvignon from reproducibility RSD. Range of measurements was actually 30 to 91% for Pinot Noir. An interoperability study (n=30) found Adams-Harbertson produces measurements that are nominally 150% of the AOAC pH differential method. Large analytical chemistry differences are: AOAC method uses Beer-Lambert equation and measures absorbance at pH 1.0 and 4.5, proposed a priori by Flueki and Francis; whereas Adams-Harbertson uses "universal" standard curve and measures absorbance ad hoc at pH 1.8 and 4.9 to reduce the effects of so-called co-pigmentation. Errors relative to AOAC are produced by Adams-Harbertson standard curve over Beer-Lambert and pH 1.8 over pH 1.0. The study recommends using AOAC Official Method 2005.02 for analysis of wine anthocyanin glycosides.
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NASA Astrophysics Data System (ADS)
Tyapkov, V. F.; Chudakova, I. Yu.; Alekseenko, O. A.
2011-08-01
Ways of improving the water chemistry used in the turbine generator stator's cooling systems at Russian nuclear power plants are considered. Data obtained from operational chemical monitoring of indicators characterizing the quality of cooling water in the turbine generator stator cooling systems of operating power units at nuclear power plants are presented.
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A new furostanol glycoside from Tribulus terrestris.
Xu, Yajuan; Liu, Yonghong; Xu, Tunhai; Xie, Shengxu; Si, Yunshan; Liu, Yue; Zhou, Haiou; Liu, Tonghua; Xu, Dongming
2010-01-27
Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furostane-20(22)-en-12-one-3beta, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside (1) on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations.
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Flavonoids of Lotus (Nelumbo nucifera) Seed Embryos and Their Antioxidant Potential.
Zhu, Mingzhi; Liu, Ting; Zhang, Chunyun; Guo, Mingquan
2017-08-01
Flavonoids from lotus (Nelumbo nucifera) seed embryos were fractionated over a macroporous resin chromatography into 2 main fractions (I and II), and subsequently identified by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS 2 ). Sixteen flavonoids were identified in lotus seed embryos, including 8 flavonoid C-glycosides and 8 flavonoid O-glycosides, in which the flavonoid C-glycosides were the main flavonoids. Among them, 2 flavonoid O-glycosides (luteolin 7-O-neohesperidoside and kaempferol 7-O-glucoside) were identified in lotus seed embryos for the 1st time. For further elucidating the effects of flavonoid C-glycosides to the bioactivities of lotus seed embryos, we compared the differences of the flavonoids and their antioxidant activities between leaves and seed embryos of lotus using the same methods. The results showed the antioxidant activity of flavonoids in lotus seed embryos was comparable or higher than that in lotus leaves, whereas the total flavonoid content in seed embryos was lower than lotus leaves which only contained flavonoid O-glycosides. The flavonoid C-glycosides of lotus seed embryos had higher antioxidant properties than the flavonoid O-glycosides presented in lotus leaves. This study suggested that the lotus seed embryos could be promising sources with antioxidant activity and used as dietary supplements for health promotion. © 2017 Institute of Food Technologists®.
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The effect of flavonol glycosides on opiate withdrawal.
Capasso, Anna
2007-07-01
Our interest has been centered on flavonol glycosides from Croton Menthodorus (Euphorbiaceae) and Aristeguietia discolor (Asteraceae). In this respect, the effect of flavonol glycosides from Croton Menthodorus (Euphorbiaceae) and Aristeguietia discolor (Asteraceae) was investigated on the naloxone-precipitated withdrawal contracture of the acute morphine-dependent guinea-pig ileum in vitro. Furthermore, the effect of these flavonol glycosides was also considered on DAGO (highly selective micro-agonist) and U50-488H (highly selective k-agonist) withdrawal to test whether the possible interaction of flavonol glycosides on opioid withdrawal involves micro- and/or k-opioid receptors. Flavonol glycosides from Croton Menthodorus (1 x 10(-5), 5 x 10(-5) and 1 x 10(-4) M) and from Aristeguietia discolor (1 x 10(-7)-1 x 10(-6)-1 x 10(-5) M) before or after the opioid agonists were able to both prevent and reverse the naloxone-induced contracture after exposure to micro (morphine and DAGO) or k (U50-488H) opiate agonists in a concentration-dependent fashion. Both acetylcholine response and electrical stimulation were reduced by flavonol glycosides treatment as well as the final opiate withdrawal was still reduced. The results of the present study indicate that flavonol glycosides were able to produce significant influence on the opiate withdrawal in vitro and these compounds were able to exert their effects both at micro and k opioid agonists.
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Khandy, M T; Titova, M V; Konstantinova, S V; Kochkin, D V; Ivanov, I M; Nosov, A M
2016-01-01
Changes in the content of the furostanol glycosides protodioscin and deltoside, particularly that of the (25S)-isomers of the glycosides, during suspension cultivation of different lines of Nepal yam (Dioscorea deltoidea Wall.) cells of the strain IFR-DM-0.5 has been investigated. The composition of furostanol glycosides has been characterized, and the dynamics of the accumulation of individual glycosides during lengthy subcultivation of cells maintained in flasks or in a barbotage bioreactor has been analyzed. A positive correlation between the growth and accumulation of substances that belonged to the class of furostanol glycosides has been demonstrated for cultured dioscorea cells, whereas the content of some of the individual glycosides varied considerably between the lines of the strain, cultures maintained under different conditions, and even between cells in different phases of the growth cycle. The increased content of (25R)-forms of the glycosides (protodioscin and deltoside) was correlated with a decrease in the cellular growth rate, whereas an increase in culture growth intensity occurred concomitantly to an increase of the amount of (25S)-isomers. This may be indicative of the specific stimulatory effect of (25S)-glycosides, but not the (25R)-forms, on cell proliferation in vitro. Thus, the concentration of (25S)-forms may increase due to the autoselection of cells capable of intensive division during prolonged cultivation.
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NASA Astrophysics Data System (ADS)
Gimenez, Sônia Maria N.; Yabe, Maria Josefa S.; Kondo, Neide K.; Mouriño, Rodrigo O.; Moura, Graziela Cristina R.
2000-02-01
Agronomy students generally lack interest in chemistry. The objective of this work was to modify the analytical chemistry curriculum to increase student interest. Samples of soils and plants prepared by students were introduced. Soil was treated with molasses residue, organic matter (chicken manure and humus obtained from goat excrement), and lime. The response of plants to the different soil treatments increased student interest in chemical analyses. Evaluation of several chemical and physicochemical parameters of samples demonstrated in a clear way the application of the theoretical and practical concepts of chemistry.
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Monoterpene glycosides from Paeonia veitchii.
Fu, Qiang; Tan, Mao-Ling; Yuan, Hai-Mei; Chen, Jiang; Fu, Jia
2017-01-01
The EtOH extract of the roots of Paeonia veitchii afforded two new monoterpene glycosides paeonidanin I (1) and paeonidanin J (2), and a new dimeric monoterpene glycoside paeonidanin K (3). Their structures were elucidated on the basis of spectroscopic means and hydrolysis products.
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Three new flavonoids, hippophins K-M, from the seed residue of Hippophae rhamnoides subsp. sinensis.
Chen, Chao; Gao, Wen; Ou-Yang, Dan-Wei; Zhang, Jing; Kong, De-Yun
2014-01-01
Three new flavonol glycosides (1-3), hippophins K-M, were isolated from the seed residue of Hippophae rhamnoides subsp. sinensis. The chemical structures of these three new compounds were identified by 1D, 2D NMR, mass spectroscopy and high resolution electrospray ionization mass spectrometry spectroscopic data and by comparison with the literature data. This report is a continuous research work on the systematic chemical investigation of plants of the genus Hippophae in our laboratory.
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Becker, Christine; Urlić, Branimir; Jukić Špika, Maja; Kläring, Hans-Peter; Krumbein, Angelika; Baldermann, Susanne; Goreta Ban, Smiljana; Perica, Slavko; Schwarz, Dietmar
2015-01-01
Reduction of nitrogen application in crop production is desirable for ecological and health-related reasons. Interestingly, nitrogen deficiency can lead to enhanced concentrations of polyphenols in plants. The reason for this is still under discussion. The plants' response to low nitrogen concentration can interact with other factors, for example radiation intensity. We cultivated red and green leaf lettuce hydroponically in a Mediterranean greenhouse, supplying three different levels of nitrogen (12 mM, 3 mM, 0.75 mM), either in full or reduced (-50%) radiation intensity. In both red and green lettuce, we found clear effects of the nitrogen treatments on growth characteristics, phenolic and photosynthetic compounds, nitrogen, nitrate and carbon concentration of the plants. Interestingly, the concentrations of all main flavonoid glycosides, caffeic acid derivatives, and sucrose increased with decreasing nitrogen concentration, whereas those of chlorophylls, β-carotene, neoxanthin, lactucaxanthin, all trans- and cis-violaxanthin decreased. The constitutive concentrations of polyphenols were lower in the green cultivar, but their relative increase was more pronounced than in the red cultivar. The constitutive concentrations of chlorophylls, β-carotene, neoxanthin, all trans- and cis-violaxanthin were similar in red and green lettuce and with decreasing nitrogen concentration they declined to a similar extent in both cultivars. We only detected little influence of the radiation treatments, e.g. on anthocyanin concentration, and hardly any interaction between radiation and nitrogen concentration. Our results imply a greater physiological plasticity of green compared to the red lettuce regarding its phenolic compounds. They support the photoprotection theory regarding anthocyanins as well as the theory that the deamination activity of phenylalanine ammonia-lyase drives phenylpropanoid synthesis.
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Biodynamic constituents in the Mexican morning glories: purgative remedies transcending boundaries.
Pereda-Miranda, Rogelio; Bah, Moustapha
2003-01-01
Jalap, a pre-Hispanic herbal remedy still considered a useful laxative, is an ingredient in some over-the-counter products sold by herbalists in contemporary Mexico. The purgative crude drugs are prepared from the roots of several morning glories species which all have been identified as members of the Ipomoea genus (Convolvulaceae). Their incorporation as therapeutical agents into Europe is an outstanding example of the assimilation of botanical drugs from the Americas as substitutes for traditional Old World remedies. Phytochemical investigations on the resin glycosides, main constituents of these drugs, were initiated during the second half of the XIX century; however, the structures of their active ingredients had remained poorly known, and still are for some members of these purgative root species. Modern analytical techniques with higher resolution capabilities (HPLC) for the isolation of the active principles of these crude drugs used in conjunction with powerful spectroscopic methods (high field NMR) have facilitated the investigation of these relevant, to the herbal product market, convolvulaceous species during the last decade. The advantages and limitations of theses techniques will be discussed. This review will also describe the ethnobotanical information associated with the Mexican morning glory species and how the traditional usages of these plants have played an important role in the selection of these materials for chemical studies. Little is as yet known about either the mechanism of purge action caused by the resin glycosides or the ecological significance of these same compounds for the producing plants. Over the five centuries of Mexican herbal medicine, one hundred years of phytochemistry has only partially elucidated the active ingredients of the jalap roots but has exemplified how to further contemporary drug discoveries through the investigation of those plants traditionally held to be economically and medicinally important in developing countries.
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Ma, Xueying; Laaksonen, Oskar; Zheng, Jie; Yang, Wei; Trépanier, Martin; Kallio, Heikki; Yang, Baoru
2016-06-01
Flavonol glycosides of wild sea buckthorn (Hippophaë rhamnoides ssp. sinensis) berries from China and cultivated berries (H. rhamnoides ssp. mongolica) from Finland and Canada were identified and quantified. Twenty-six flavonol glycosides were found with isorhamnetin and quercetin as the major aglycones. The contents of flavonol glycosides ranged 23-250 mg/100 g fresh berries and were significantly higher in the berries of ssp. sinensis than in those of ssp. mongolica. Among the cultivars of ssp. mongolica, the berries of 'Oranzhevaya' had the lowest (23 mg/100 g) content, and those of 'Prevoshodnaya' the highest content of flavonol glycosides (80 mg/100 g). Within the ssp. mongolica, the samples from Kittilä (Northern Finland) had higher levels of most flavonol glycosides than those from Turku (Southern Finland) and Québec. Among the ssp. sinensis berries of different growth sites, increasing trends were detected in the contents of most of the compounds as the altitude increased and as the latitude decreased. The wild berries (ssp. sinensis) from Sichuan had remarkably high contents and unique profiles of flavonol glycosides. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Synthesis and Biological Testing of Novel Glucosylated Epigallocatechin Gallate (EGCG) Derivatives.
Zhang, Xin; Wang, Jing; Hu, Jiang-Miao; Huang, Ye-Wei; Wu, Xiao-Yun; Zi, Cheng-Ting; Wang, Xuan-Jun; Sheng, Jun
2016-05-11
Epigallocatechin gallate (EGCG) is the most abundant component of green tea catechins and has strong physiological activities. In this study, two novel EGCG glycosides (EGCG-G1 and EGCG-G2) were chemoselectively synthesized by a chemical modification strategy. Each of these EGCG glycosides underwent structure identification, and the structures were assigned as follows: epigallocatechin gallate-4''-O-β-d-glucopyranoside (EGCG-G1, 2) and epigallocatechin gallate-4',4''-O-β-d-gluco-pyranoside (EGCG-G2, 3). The EGCG glycosides were evaluated for their anticancer activity in vitro against two human breast cell lines (MCF-7 and MDA-MB-231) using MTT assays. The inhibition rate of EGCG glycosides (EGCG-G1 and EGCG-G2) is not obvious. The EGCG glycosides are more stable than EGCG in aqueous solutions, but exhibited decreasing antioxidant activity in the DPPH radical-scavenging assay (EGCG > EGCG-G2 > EGCG-G1). Additionally, the EGCG glycosides exhibited increased water solubility: EGCG-G2 and EGCG-G1 were 15 and 31 times as soluble EGCG, respectively. The EGCG glycosides appear to be useful, and further studies regarding their biological activity are in progress.
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Acylated-oxypregnane glycosides from the roots of Asclepias syriaca.
Warashina, Tsutomu; Noro, Tadataka
2009-02-01
Twenty new pregnane glycosides were obtained from the roots of Asclepias syriaca L. (Asclepiadaceae). These glycosides were confirmed to contain ikemagenin, 12-O-nicotinoyllineolon, 5alpha,6-dihydroikemagenin, and 12-O-tigloylisolineolon, as their aglycones, using both spectroscopic and chemical methods.
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NASA Astrophysics Data System (ADS)
Szeleszczuk, Łukasz; Gubica, Tomasz; Zimniak, Andrzej; Pisklak, Dariusz M.; Dąbrowska, Kinga; Cyrański, Michał K.; Kańska, Marianna
2017-10-01
A convenient method for the indirect crystal structure verification of methyl glycosides was demonstrated. Single-crystal X-ray diffraction structures for methyl glycoside acetates were deacetylated and subsequently subjected to DFT calculations under periodic boundary conditions. Solid-state NMR spectroscopy served as a guide for calculations. A high level of accuracy of the modelled crystal structures of methyl glycosides was confirmed by comparison with published results of neutron diffraction study using RMSD method.
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Potential plant poisonings in dogs and cats in southern Africa.
Botha, C J; Penrith, M L
2009-06-01
Plant poisoning occurs less commonly in dogs and cats than in herbivorous livestock, but numerous cases have been documented worldwide, most of them caused by common and internationally widely cultivated ornamental garden and house plants. Few cases of poisoning of cats and dogs have been reported in southern Africa, but many of the plants that have caused poisoning in these species elsewhere are widely available in the subregion and are briefly reviewed in terms of toxic principles, toxicity, species affected, clinical signs, and prognosis. The list includes Melia azedarach (syringa), Brunfelsia spp. (yesterday, today and tomorrow), Datura stramonium (jimsonweed, stinkblaar), a wide variety of lilies and lily-like plants, cycads, plants that contain soluble oxalates, plants containing cardiac glycosides and other cardiotoxins and euphorbias (Euphorbia pulcherrima, E. tirucalli). Poisoning by plant products such as macadamia nuts, onions and garlic, grapes and raisins, cannabis (marijuana, dagga) or hashish and castor oil seed or seedcake is also discussed. Many of the poisonings are not usually fatal, but others frequently result in death unless rapid action is taken by the owner and the veterinarian, underlining the importance of awareness of the poisonous potential of a number of familiar plants.
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Li, Yushan; Ohizumi, Yasushi
2004-07-01
20 medicinal plants of Paraguay and 3 medicinal plants of Thailand were examined on nerve growth factor (NGF)-potentiating activities in PC12D cells. The trail results demonstrated that the methanol extracts of four plants, Verbena littoralis, Scoparia dulcis, Artemisia absinthium and Garcinia xanthochymus, markedly enhanced the neurite outgrowth induced by NGF from PC12D cells. Furthermore, utilizing the bioactivity-guided separation we successfully isolated 32, 4 and 5 constituents from V. littoralis, S. dulcis and G. xanthochymus, respectively, including nine iridoid and iridoid glucosides (1-9), two dihydrochalcone dimers (10 and 11), two flavonoids and three flavonoid glycosides (12-16), two sterols (17 and 18), ten triterpenoids (19-28), five xanthones (29-33), one naphthoquinone (34), one benzenepropanamide (35), four phenylethanoid glycosides (36-39) and two other compounds (40 and 41). Among which, 15 compounds (1-4, 10-11, 14-18, 29-31 and 34) were new natural products. The results of pharmacological trails verified that littoralisone (1), gelsemiol (5), 7a-hydroxysemperoside aglucone (6), verbenachalcone (10), littorachalcone (11), stigmast-5-ene 3beta,7alpha,22alpha-triol (18), ursolic acid (19), 3beta-hydroxyurs-11-en-28,13beta-olide (24), oleanolic acid (25), 2alpha,3beta-dihydroxyolean-12-en-28-oic acid (26), 1,4,5,6-tetrahydroxy-7,8-di(3-methylbut-2-enyl)xanthone (29), 1,2,6-trihydroxy-5-methoxy-7-(3-methylbut-2-enyl)xanthone (30), 1,3,5,6-tetrahydroxy-4,7,8-tri(3-methyl-2-butenyl)xanthone (31), 12b-hydroxy-des-D-garcigerrin A (32), garciniaxanthone E (33) and (4R)-4,9-dihydroxy-8-methoxy-alpha-lapachone (34) elicited marked enhancement of NGF-mediated neurite outgrowth in PC12D cells. These substances may contribute to the basic study and the medicinal development for the neurodegenerative disorder.
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smRNAome profiling to identify conserved and novel microRNAs in Stevia rebaudiana Bertoni
2012-01-01
Background MicroRNAs (miRNAs) constitute a family of small RNA (sRNA) population that regulates the gene expression and plays an important role in plant development, metabolism, signal transduction and stress response. Extensive studies on miRNAs have been performed in different plants such as Arabidopsis thaliana, Oryza sativa etc. and volume of the miRNA database, mirBASE, has been increasing on day to day basis. Stevia rebaudiana Bertoni is an important perennial herb which accumulates high concentrations of diterpene steviol glycosides which contributes to its high indexed sweetening property with no calorific value. Several studies have been carried out for understanding molecular mechanism involved in biosynthesis of these glycosides, however, information about miRNAs has been lacking in S. rebaudiana. Deep sequencing of small RNAs combined with transcriptomic data is a powerful tool for identifying conserved and novel miRNAs irrespective of availability of genome sequence data. Results To identify miRNAs in S. rebaudiana, sRNA library was constructed and sequenced using Illumina genome analyzer II. A total of 30,472,534 reads representing 2,509,190 distinct sequences were obtained from sRNA library. Based on sequence similarity, we identified 100 miRNAs belonging to 34 highly conserved families. Also, we identified 12 novel miRNAs whose precursors were potentially generated from stevia EST and nucleotide sequences. All novel sequences have not been earlier described in other plant species. Putative target genes were predicted for most conserved and novel miRNAs. The predicted targets are mainly mRNA encoding enzymes regulating essential plant metabolic and signaling pathways. Conclusions This study led to the identification of 34 highly conserved miRNA families and 12 novel potential miRNAs indicating that specific miRNAs exist in stevia species. Our results provided information on stevia miRNAs and their targets building a foundation for future studies to understand their roles in key stevia traits. PMID:23116282
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smRNAome profiling to identify conserved and novel microRNAs in Stevia rebaudiana Bertoni.
Mandhan, Vibha; Kaur, Jagdeep; Singh, Kashmir
2012-11-01
MicroRNAs (miRNAs) constitute a family of small RNA (sRNA) population that regulates the gene expression and plays an important role in plant development, metabolism, signal transduction and stress response. Extensive studies on miRNAs have been performed in different plants such as Arabidopsis thaliana, Oryza sativa etc. and volume of the miRNA database, mirBASE, has been increasing on day to day basis. Stevia rebaudiana Bertoni is an important perennial herb which accumulates high concentrations of diterpene steviol glycosides which contributes to its high indexed sweetening property with no calorific value. Several studies have been carried out for understanding molecular mechanism involved in biosynthesis of these glycosides, however, information about miRNAs has been lacking in S. rebaudiana. Deep sequencing of small RNAs combined with transcriptomic data is a powerful tool for identifying conserved and novel miRNAs irrespective of availability of genome sequence data. To identify miRNAs in S. rebaudiana, sRNA library was constructed and sequenced using Illumina genome analyzer II. A total of 30,472,534 reads representing 2,509,190 distinct sequences were obtained from sRNA library. Based on sequence similarity, we identified 100 miRNAs belonging to 34 highly conserved families. Also, we identified 12 novel miRNAs whose precursors were potentially generated from stevia EST and nucleotide sequences. All novel sequences have not been earlier described in other plant species. Putative target genes were predicted for most conserved and novel miRNAs. The predicted targets are mainly mRNA encoding enzymes regulating essential plant metabolic and signaling pathways. This study led to the identification of 34 highly conserved miRNA families and 12 novel potential miRNAs indicating that specific miRNAs exist in stevia species. Our results provided information on stevia miRNAs and their targets building a foundation for future studies to understand their roles in key stevia traits.
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Evaluation of the potential carcinogenic activity of Senna and Cascara glycosides for the rat colon.
Mereto, E; Ghia, M; Brambilla, G
1996-03-19
Anthraquinone glycosides of Senna and Cascara were investigated for their ability to induce aberrant crypt foci (ACF) in the rat colon mucosa, which are considered putative preneoplastic lesions. Dietary exposure to high doses of these glycosides for 56 successive days did not cause the appearance of ACF or increase in incidence of ACF induced by 1,2-dimethyl-hydrazine (DMH). However, in rats treated with both DMH and the highest dose of glycosides, the average number of aberrant crypts per focus, considered a consistent predictor of tumor outcome, was higher than in rats given DMH alone. These findings suggest that Senna and Cascara glycoside might behave as weak promoters in rat colon carcinogenesis.
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[Flavonols and flavones of vegetables. VII. Flavonols of leek, chive and garlic (author's transl)].
Starke, H; Herrmann, K
1976-01-01
Green leaves of leek and chive mainly contain kaempferol glycosides, with mono- and di-glycosides dominating in leek and di- and tri-glycosides in chive. In leek glucose is dominant as sugar component compared to xylose; in chive we found glucose and galactose. Kaempferol-3-beta-D-glucoside and kaempferol-3-xylosyl-beta-D-glucoside were isolated from leek and the 3-beta-D-glucosides of kaempferol, quercetin and isorhamnetin as by-glycosides from chive. In leek traces of quercetin-3-glucoside were identified by tlc, but no spiraeoside (quercetin-4'-glucoside) could be detected in the two species. The bulbs of garlic and leek contain only few milligram of glycosides of kaempferol and quercetin per kg fresh weight.
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Primary water chemistry improvement for radiation exposure reduction at Japanese PWR Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nishizawa, Eiichi
1995-03-01
Radiation exposure during the refueling outages at Japanese Pressurized Water Reactor (PWR) Plants has been gradually decreased through continuous efforts keeping the radiation dose rates at relatively low level. The improvement of primary water chemistry in respect to reduction of the radiation sources appears as one of the most important contributions to the achieved results and can be classified by the plant operation conditions as follows
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USDA-ARS?s Scientific Manuscript database
The structural analysis of complex carbohydrates typically requires the assignment of three parameters: monosaccharide composition, the position of glycosidic linkages between monosaccharides, and the position and nature of non-carbohydrate substituents. The glycosidic linkage positions are often de...
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A Novel Diterpene Glycoside with Nine Glucose Units from Stevia rebaudiana Bertoni.
Prakash, Indra; Ma, Gil; Bunders, Cynthia; Charan, Romila D; Ramirez, Catherine; Devkota, Krishna P; Snyder, Tara M
2017-01-31
Following our interest in new diterpene glycosides with better taste profiles than that of Rebaudioside M, we have recently isolated and characterized Rebaudioside IX-a novel steviol glycoside-from a commercially-supplied extract of Stevia rebaudiana Bertoni. This molecule contains a hexasaccharide group attached at C-13 of the central diterpene core, and contains three additional glucose units when compared with Rebaudioside M. Here we report the complete structure elucidation-based on extensive Nuclear Magnetic Resonance (NMR) analysis (1H, 13C, Correlation Spectroscopy (COSY), Heteronuclear Single Quantum Coherence-Distortionless Enhancement Polarization Transfer (HSQC-DEPT), Heteronuclear Multiple Bond Correlation (HMBC), 1D Total Correlation Spectroscopy (TOCSY), Nuclear Overhauser Effect Spectroscopy (NOESY)) and mass spectral data-of this novel diterpene glycoside with nine sugar moieties and containing a relatively rare 16 α-linked glycoside. A steviol glycoside bearing nine glucose units is unprecedented in the literature, and could have an impact on the natural sweetener catalog.
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Roulard, Romain; Fontaine, Jean-Xavier; Jamali, Arash; Cailleu, Dominique; Tavernier, Reynald; Guillot, Xavier; Rhazi, Larbi; Petit, Emmanuel; Molinie, Roland; Mesnard, François
2017-12-01
This report describes a routine method taking less than 20 min to quantify cyanogenic glycosides such as linustatin and neolinustatin from flaxseeds (Linum usitatissimum L.) using 1 H nuclear magnetic resonance. After manual dehulling, a higher linustatin content was shown in the almond fraction, while neolinustatin and total cyanogenic glycoside contents were significantly higher in hulls. Linustatin and neolinustatin were quantified in seven cultivars grown in two locations in three different years. Linustatin, neolinustatin, and total cyanogenic glycosides ranged between 91 and 267 mg/100 g, 78-272 mg/100 g, and 198-513 mg/100 g dry weight flaxseeds, respectively. NMR revealed differences of up to 70% between samples with standard deviation variations lower than 6%. This study shows that NMR is a very suitable tool to perform flaxseed varietal selection for the cyanogenic glycoside content. Graphical abstract qNMR can be used to perform flaxseed varietal selection for the cyanogenic glycoside content.
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Vegetation effects on soil organic matter chemistry of aggregate fractions in a Hawaiian forest
USDA-ARS?s Scientific Manuscript database
We examined chemical changes from live plant tissue to soil organic matter (SOM) to determine the persistence of individual plant compounds into soil aggregate fractions. We characterized the tissue chemistry of a slow- (Dicranopteris linearis) and fast-decomposing species (Cheirodendron trigynum) a...
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Plant latex: a promising antifungal agent for post harvest disease control.
Sibi, G; Wadhavan, Rashmi; Singh, Sneha; Shukla, Abhilasha; Dhananjaya, K; Ravikumar, K R; Mallesha, H
2013-12-01
Bioactive compounds from plant latex are potential source of antifungic against post harvest pathogens. Latex from a total of seven plant species was investigated for its phytochemical and antifungal properties. Six fungi namely Aspergillus fumigatus, A. niger, A. terreus, F. solani, P. digitatum and R. arrhizus were isolated from infected fruits and vegetables and tested against various solvent extracts of latex. Analysis of latex extracts with phytochemical tests showed the presence of alkaloids, flavonoids, glycosides, phenols, saponins, steroids, tannins and terpenoids. Antifungal assay revealed the potential inhibitory activity of petroleum ether extracts against the postharvest fungal isolates. Various degree of sensitivity was observed irrespective of plant species studied with A. terreus and P. digitatum as the most susceptible ones. F. solani and A. fumigatus were moderately sensitive to the latex extracts tested. Among the plants, latex of Thevetia peruviana (75.2%) and Artocarpus heterophyllus (64.8%) were having potential antifungal activity against the isolates followed by Manilkara zapota (51.1%). In conclusion, use of plant latex makes interest to control postharvest fungal diseases and is fitting well with the concept of safety for human health and environment.
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Phytosteryl glycosides reduce cholesterol absorption: mechanisms in mice
USDA-ARS?s Scientific Manuscript database
Phytosteryl glycosides occur in natural foods but little is known about their metabolism and bioactivity. Purified acylated steryl glycosides (ASG) were compared with phytosteryl esters (PSE) in mice. Animals on a phytosterol-free diet received ASG or PSE by gavage in purified soybean oil along with...
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Optimization of the water chemistry of the primary coolant at nuclear power plants with VVER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barmin, L. F.; Kruglova, T. K.; Sinitsyn, V. P.
2005-01-15
Results of the use of automatic hydrogen-content meter for controlling the parameter of 'hydrogen' in the primary coolant circuit of the Kola nuclear power plant are presented. It is shown that the correlation between the 'hydrogen' parameter in the coolant and the 'hydrazine' parameter in the makeup water can be used for controlling the water chemistry of the primary coolant system, which should make it possible to optimize the water chemistry at different power levels.
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Phenolic and lignan glycosides from the butanol extract of Averrhoa carambola L. root.
Wen, Qingwei; Lin, Xing; Liu, Yeqi; Xu, Xiaohui; Liang, Tao; Zheng, Ni; Kintoko; Huang, Renbin
2012-10-19
Fifteen compounds, which included six chiral lignans and nine phenolic glycosides, were separated from the butanol fraction of Averrhoa carambola L. root and identified. All of the compounds, namely 3,4,5-trimethoxyphenol-1-O-β-D-glucopyranoside, benzyl-1-O-β-D-glucopyranoside, (+)-5'-methoxyisolariciresinol 3α-O-β-D-gluco-pyranoside, (+)-isolariciresinol 3α-O-β-D-glucopyranoside, koaburaside, (+)-lyoniresinol 3α-O-β-D-glucopyranoside, (-)-lyoniresinol 3α-O-β-D-glucopyranoside, (-)-5'-methoxyisolariciresinol 3α-O-β-D-glucopyranoside, (-)-isolariciresinol 3α-O-β-D-glucopyranoside, 3,5-dimethoxy-4-hydroxyphenyl 1-O-β-apiofuranosyl (1''→6')-O-β-D-glucopyranoside, 3,4,5-trimethoxyphenyl 1-O-β-apiofuranosyl (1''→6')-β-gluco-pyranoside, methoxyhydroquinone-4-β-D-glucopyranoside, (2S)-2-O-β-D-gluco-pyranosyl-2-hydroxyphenylacetic acid, 3-hydroxy-4-methoxyphenol 1-O-β-D-apio-furanosyl-(1''→6')-O-β-D-glucopyranoside and 4-hydroxy-3-methoxyphenol 1-O-β-D-apiofuranosyl-(1''→6')-O-β-D-glucopyranoside were isolated from this plant for the first time.
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Carboxymethyl- and carboxyl-catechins from ripe Pu-er tea.
Tian, Li-Wen; Tao, Mu-Ke; Xu, Min; Hu, Jing; Zhu, Hong-Tao; Xiong, Wen-Yong; Wang, Dong; Yang, Chong-Ren; Zhang, Ying-Jun
2014-12-17
Ripe Pu-er tea, a special microbial postfermented tea originated from Yunnan Province, China, since ancient times, is made from green Pu-er tea prepared from the leaves of Camellia sinensis var. assamica (Theaceae). Chemical investigation on thearubigin (n-BuOH-soluble) fraction of the commercial ripe Pu-er tea, led to the identification of four new flavan-3-ol derivatives, 8-carboxymethyl-(+)-catechin (1), 8-carboxymethyl-(+)-catechin methyl ester (2), 6-carboxymethyl-(+)-catechin (3), and 6-carboxyl-(-)-gallocatechin (4), together with 18 known compounds, including other three flavan-3-ol derivatives (5-7), 10 flavonoid glycosides (8-17), two hydrolyzable tannins (18 and 19), two quinic acid derivatives (20-21), and a purine alkaloid (22). Flavonoid glycosides 8-11 are reported from tea plants for the first time. The thearubigin fraction of ripe Pu-er tea was qualitatively analyzed by HPLC, and gallic acid was found to be the major component. Compounds 4, 6-17, 21 and 22 were tested for their acute activities on insulin sensitivity in differentiated 3T3-L1 adipocytes, but none of them showed significant bioactivity at a concentration of 10 μM.
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Urtica spp.: Phenolic composition, safety, antioxidant and anti-inflammatory activities.
Carvalho, Ana Rita; Costa, Gustavo; Figueirinha, Artur; Liberal, Joana; Prior, João A V; Lopes, Maria Celeste; Cruz, Maria Teresa; Batista, Maria Teresa
2017-09-01
Urtica dioica and other less studied Urtica species (Urticaceae) are often used as a food ingredient. Fifteen hydroxycinnamic acid derivatives and sixteen flavonoids, flavone and flavonol-type glycosides were identified in hydroalcoholic extracts from aerial parts of Urtica dioica L., Urtica urens L. and Urtica membranacea using HPLC-PDA-ESI/MS n . Among them, the 4-caffeoyl-5-p-coumaroylquinic acid and three statin-like 3-hydroxy-3-methylglutaroyl flavone derivatives were identified for the first time in Urtica urens and U. membranacea respectively. Urtica membranacea showed the higher content of flavonoids, mainly luteolin and apigenin C-glycosides, which are almost absent in the other species studied. In vitro, Urtica dioica exhibited greater antioxidant activity but Urtica urens exhibited stronger anti-inflammatory potential. Interestingly, statin-like compounds detected in Urtica membranacea have been associated with hypocholesterolemic activity making this plant interesting for future investigations. None of the extracts were cytotoxic to macrophages and hepatocytes in bioactive concentrations (200 and 350μg/mL), suggesting their safety use in food applications. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Antiproliferative constituents in plants 9. Aerial parts of Lippia dulcis and Lippia canescens.
Abe, Fumiko; Nagao, Tsuneatsu; Okabe, Hikaru
2002-07-01
The antiproliferative constituents in the MeOH extracts of the aerial parts of Lippia dulcis Trev. and Lippia canescens Kunth (Verbenaceae) were investigated. Activity-guided chemical investigation of the MeOH extracts resulted in the isolation of the three bisabolane-type sesquiterpenes [(+)-hernandulcin (1), (-)-epihernandulcin (2), and (+)-anymol (3)] and four phenylethanoid glycosides [acteoside (4), isoacteoside (5), martynoside (6), and a new diacetylmartynoside (7)] from the former, and four phenylethanoid glycosides [acteoside (4), isoacteoside (5), arenarioside (8), and leucosceptoside A (9)] and three flavones [desmethoxycentaureidin (10), eupafolin (11), and 6-hydroxyluteolin (12)] from the latter. Antiproliferative activity of the isolated compounds against murine melanoma (B16F10), human gastric adenocarcinoma (MK-1), and human uterine carcinoma (HeLa) cells was estimated. (+)-Anymol (3), acteoside (4), isoacteoside (5), arenarioside (8), eupafolin (11), and 6-hydroxyluteolin (12) had GI50 values of 10-16 microM against B16F10 cell. Desmethoxycentaureidin (10) and eupafolin (11) showed high inhibitory activity against HeLa cell growth (GI50 9 microM, and 6 microM, respectively).
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An efficient fermentation method for the degradation of cyanogenic glycosides in flaxseed.
Wu, C-F; Xu, X-M; Huang, S-H; Deng, M-C; Feng, A-J; Peng, J; Yuan, J-P; Wang, J-H
2012-01-01
Recently, flaxseed has become increasingly popular in the health food market because it contains a considerable amount of specific beneficial nutrients such as lignans and omega-3 fatty acids. However, the presence of cyanogenic glycosides (CGs) in flaxseed severely limits the exploitation of its health benefits and nutritive value. We, therefore, developed an effective fermentation method, optimised by response surface methodology (RSM), for degrading CGs with an enzymatic preparation that includes 12.5% β-glucosidase and 8.9% cyanide hydratase. These optimised conditions resulted in a maximum CG degradation level of 99.3%, reducing the concentration of cyanide in the flaxseed power from 1.156 to 0.015 mg g(-1) after 48 h of fermentation. The avoidance of steam heat to evaporate hydrocyanic acid (HCN) results in lower energy consumption and no environmental pollution. In addition, the detoxified flaxseed retained the beneficial nutrients, lignans and fatty acids at the same level as untreated flaxseed, and this method could provide a new means of removing CGs from other edible plants, such as cassava, almond and sorghum by simultaneously expressing cyanide hydratase and β-glucosidase.
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Yoneda, Yuki; Nakashima, Hiroshi; Miyasaka, Juro; Ohdoi, Katsuaki; Shimizu, Hiroshi
2017-05-01
Stevia rebaudiana (Bertoni) Bertoni is a plant that biosynthesizes a group of natural sweeteners that are up to approximately 400 times sweeter than sucrose. The sweetening components of S. rebaudiana are steviol glycosides (SGs) that partially share their biosynthesis pathway with gibberellins (GAs). However, the molecular mechanisms through which SGs levels can be improved have not been studied. Therefore, transcription levels of several SG biosynthesis-related genes were analyzed under several light treatments involved in GA biosynthesis. We detected higher transcription of UGT85C2, which is one of the UDP-glycosyltransferases (UGTs) involved in catalyzing the sugar-transfer reaction, under red/far-red (R/FR) 1.22 light-emitting diodes (LEDs) and blue LEDs treatment. In this study, it was demonstrated that transcription levels of SG-related genes and the SGs content are affected by light treatments known to affect the GA contents. It is expected that this approach could serve as a practical way to increase SG contents using specific light treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Fruit Seeds of the Rosaceae Family: A Waste, New Life, or a Danger to Human Health?
Senica, Mateja; Stampar, Franci; Veberic, Robert; Mikulic-Petkovsek, Maja
2017-12-06
In fruit production seeds are mostly regarded as waste, but for plants they represent a beginning of new life. Seeds accumulate toxic or health-beneficial compounds, and the elucidation of their metabolic profile is especially important to people who consume the entire fruit, including the seeds. The present research quantifies the levels of bioactive compounds (phenolics and cyanogenic glycosides (CGG)) in fruit seeds of 35 cultivars belonging to 6 different fruit species. High-performance liquid chromatography and mass spectrophotometry were used to detect and identify the studied compounds. Significant differences in the content of individual bioactive compounds as well as their groups were recorded (p < 0.05). For the first time neoamygdalin and prunasin were detected in a number of fruit cultivars. All fruit seeds, except pears, accumulated from 2- to 46-fold higher levels of CGG than phenolics. On average, seeds contained from 75.46 to 1648.14 μg/g phenolics and from 46.39 to 4374.31 μg/g CGG. The study also clarifies the new lethal dose for cyanogenic glycosides.
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Crystal structure and genetic modifications of FI-CMCase from Aspergillus aculeatus F-50.
Huang, Jian-Wen; Liu, Weidong; Lai, Hui-Lin; Cheng, Ya-Shan; Zheng, Yingying; Li, Qian; Sun, Hong; Kuo, Chih-Jung; Guo, Rey-Ting; Chen, Chun-Chi
2016-09-16
Cellulose is the major component of the plant cell wall and the most abundant renewable biomass on earth, and its decomposition has proven to be very useful in many commercial applications. Endo-1,4-β-d-glucanase (EC 3.2.1.4; endoglucanase), which catalyzes the random hydrolysis of 1,4-β-glycosidic bonds of the cellulose main chain to cleave cellulose into smaller fragments, is the key cellulolytic enzyme. An endoglucanase isolated from Aspergillus aculeatus F-50 (FI-CMCase), which is classified into the glycoside hydrolase (GH) family 12, was demonstrated to be effectively expressed in the industrial strain Pichia pastoris. Here, the crystal structure and complex structures of P. pastoris-expressed FI-CMCase were solved to high resolution. The overall structure is analyzed and compared to other GH12 members. In addition, the substrate-surrounding residues were engineered to search for variants with improved enzymatic activity. Among 14 mutants constructed, one with two-fold increase in protein expression was identified, which possesses a potential to be further developed as a commercial enzyme product. Copyright © 2016 Elsevier Inc. All rights reserved.
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Brouns, Stan J. J.; Smits, Nicole; Wu, Hao; Snijders, Ambrosius P. L.; Wright, Phillip C.; de Vos, Willem M.; van der Oost, John
2006-01-01
Sulfolobus solfataricus is an aerobic crenarchaeon that thrives in acidic volcanic pools. In this study, we have purified and characterized a thermostable α-galactosidase from cell extracts of S. solfataricus P2 grown on the trisaccharide raffinose. The enzyme, designated GalS, is highly specific for α-linked galactosides, which are optimally hydrolyzed at pH 5 and 90°C. The protein consists of 74.7-kDa subunits and has been identified as the gene product of open reading frame Sso3127. Its primary sequence is most related to plant enzymes of glycoside hydrolase family 36, which are involved in the synthesis and degradation of raffinose and stachyose. Both the galS gene from S. solfataricus P2 and an orthologous gene from Sulfolobus tokodaii have been cloned and functionally expressed in Escherichia coli, and their activity was confirmed. At present, these Sulfolobus enzymes not only constitute a distinct type of thermostable α-galactosidases within glycoside hydrolase clan D but also represent the first members from the Archaea. PMID:16547025
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Crystal structure of a putative exo-β-1,3-galactanase from Bifidobacterium bifidum S17
Godoy, Andre S.; de Lima, Mariana Z. T.; Camilo, Cesar M.; Polikarpov, Igor
2016-01-01
Given the current interest in second-generation biofuels, carbohydrate-active enzymes have become the most important tool to overcome the structural recalcitrance of the plant cell wall. While some glycoside hydrolase families have been exhaustively described, others remain poorly characterized, especially with regard to structural information. The family 43 glycoside hydrolases are a diverse group of inverting enzymes; the available structure information on these enzymes is mainly from xylosidases and arabinofuranosidase. Currently, only one structure of an exo-β-1,3-galactanase is available. Here, the production, crystallization and structure determination of a putative exo-β-1,3-galactanase from Bifidobacterium bifidum S17 (BbGal43A) are described. BbGal43A was successfully produced and showed activity towards synthetic galactosides. BbGal43A was subsequently crystallized and data were collected to 1.4 Å resolution. The structure shows a single-domain molecule, differing from known homologues, and crystal contact analysis predicts the formation of a dimer in solution. Further biochemical studies are necessary to elucidate the differences between BbGal43A and its characterized homologues. PMID:27050262
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Jiang, Bei; Kronenberg, Fredi; Nuntanakorn, Paiboon; Qiu, Ming-Hua; Kennelly, Edward J.
2011-01-01
Black cohosh (Actaea racemosa L., syn. Cimicifuga racemosa L.) has become increasingly popular as a dietary supplement in the United States for the treatment of symptoms related to menopause, but the botanical authenticity of most products containing black cohosh has not been evaluated, nor is manufacturing highly regulated in the United States. In this study, 11 black cohosh products were analyzed for triterpene glycosides, phenolic constituents, and formononetin by high-performance liquid chromatography–photodiode array detection and a new selected ion monitoring liquid chromatography–mass spectrometry method. Three of the 11 products were found to contain the marker compound cimifugin and not cimiracemoside C, thereby indicating that these plants contain Asian Actaea instead of black cohosh. One product contained both black cohosh and an Asian Actaea species. For the products containing only black cohosh, there was significant product-to-product variability in the amounts of the selected triterpene glycosides and phenolic constituents, and as expected, no formononetin was detected. PMID:16637680
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New cardenolide and acylated lignan glycosides from the aerial parts of Asclepias curassavica.
Warashina, Tsutomu; Shikata, Kimiko; Miyase, Toshio; Fujii, Satoshi; Noro, Tadataka
2008-08-01
Three new cardenolide glycosides and six new acylated lignan glycosides were obtained along with nineteen known compounds from the aerial parts of Asclepias curassavica L. (Asclepiadaceae). The structure of each compound was determined based on interpretations of NMR and MS measurements and chemical evidence.
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Rui, Wen; Chen, Hongyuan; Tan, Yuzhi; Zhong, Yanmei; Feng, Yifan
2010-05-01
A rapid method for the analysis of the main components of the total glycosides of Ranunculus japonicus (TGOR) was developed using ultra-performance liquid chromatography with quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS). The separation analysis was performed on a Waters Acquity UPLC system and the accurate mass of molecules and their fragment ions were determined by Q-TOF MS. Twenty compounds, including lactone glycosides, flavonoid glycosides and flavonoid aglycones, were identified and tentatively deduced on the basis of their elemental compositions, MS/MS data and relevant literature. The results demonstrated that lactone glycosides and flavonoids were the main constituents of TGOR. Furthermore, an effective and rapid pattern was established allowing for the comprehensive and systematic characterization of the complex samples.
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Stability of steviol glycosides in several food matrices.
Jooken, Etienne; Amery, Ruis; Struyf, Tom; Duquenne, Barbara; Geuns, Jan; Meesschaert, Boudewijn
2012-10-24
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.
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Watkins, Oliver C; Joyce, Nigel I; Gould, Nick; Perry, Nigel B
2018-04-27
Some honeys contain the neurotoxin tutin (1) plus hyenanchin (2), 2-(β-d-glucopyranosyl)tutin (3), and 2-[6'-(α-d-glucopyranosyl)-β-d-glucopyranosyl]tutin (4). These honeys are made by bees collecting honeydew from passionvine hoppers feeding on the sap of tutu plants ( Coriaria spp.). We report a LC-MS study showing that all these picrotoxanes are of plant, not insect, origin. Hyenanchin was barely detectable and the diglucoside was not detectable in C. arborea leaves, but tutu phloem sap contained all four compounds at concentrations up to the highest found in honeydew. It is proposed that the diglucoside may function as a transport form of tutin, analogous to sucrose transport in phloem.
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[Induction of polygalacturonases important in pathogenicity of Pseudomonas solanacearum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-01-01
Recent studies on the importance of hydroxyproline-rich glycoproteins (HPRG's) in the nature and function of plant cell walls have led to the question as to whether proteolytic enzymes are also involved in tissue maceration and act in concert with other cell wall degrading enzymes in the process. The primary objective of this research was to determine whether proteolytic enzymes, in combination with other enzymes, are involved in the degradation of plant cell walls and thus may be essential for pathogenesis by certain soft rot bacteria. The proteolytic enzymes of Erwinia carotovora subsp.carotovora (Ecc) grown on various media were examined bymore » isoelectrofocusing in polyacrylamide gels over a pH range of 3-10. In addition to the main protease present in culture filtrates, low concentrations of several other proteases were present in extracts from potato tubers infected by Ecc. These enzymes degraded gelatin, soluble collagen, and Hide Powder Azure, and showed weak activity on casein, but did not degrade insoluble collagen or elastin. Ecc proteases appear capable of degrading at least one type of cell wall protein in vitro, but we were unable to obtain evidence that these proteases can attack cell wall proteins in muro. The results indicate that some glycosidic alkali- labile bonds have to be broken befor Ecc proteases can degrade cell wall proteins. Thus, these proteases may play a role in cell wall degradation only when acting in concert with other enzymes that split glycosidic bonds.« less
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[Induction of polygalacturonases important in pathogenicity of Pseudomonas solanacearum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-12-31
Recent studies on the importance of hydroxyproline-rich glycoproteins (HPRG`s) in the nature and function of plant cell walls have led to the question as to whether proteolytic enzymes are also involved in tissue maceration and act in concert with other cell wall degrading enzymes in the process. The primary objective of this research was to determine whether proteolytic enzymes, in combination with other enzymes, are involved in the degradation of plant cell walls and thus may be essential for pathogenesis by certain soft rot bacteria. The proteolytic enzymes of Erwinia carotovora subsp.carotovora (Ecc) grown on various media were examined bymore » isoelectrofocusing in polyacrylamide gels over a pH range of 3-10. In addition to the main protease present in culture filtrates, low concentrations of several other proteases were present in extracts from potato tubers infected by Ecc. These enzymes degraded gelatin, soluble collagen, and Hide Powder Azure, and showed weak activity on casein, but did not degrade insoluble collagen or elastin. Ecc proteases appear capable of degrading at least one type of cell wall protein in vitro, but we were unable to obtain evidence that these proteases can attack cell wall proteins in muro. The results indicate that some glycosidic alkali- labile bonds have to be broken befor Ecc proteases can degrade cell wall proteins. Thus, these proteases may play a role in cell wall degradation only when acting in concert with other enzymes that split glycosidic bonds.« less
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Ksouri, Riadh; Ksouri, Wided Megdiche; Jallali, Inès; Debez, Ahmed; Magné, Christian; Hiroko, Isoda; Abdelly, Chedly
2012-12-01
Salt-tolerant plants grow in a wide variety of saline habitats, from coastal regions, salt marshes and mudflats to inland deserts, salt flats and steppes. Halophytes living in these extreme environments have to deal with frequent changes in salinity level. This can be done by developing adaptive responses including the synthesis of several bioactive molecules. Consequently, several salt marsh plants have traditionally been used for medical, nutritional, and even artisanal purposes. Currently, an increasing interest is granted to these species because of their high content in bioactive compounds (primary and secondary metabolites) such as polyunsaturated fatty acids, carotenoids, vitamins, sterols, essential oils (terpenes), polysaccharides, glycosides, and phenolic compounds. These bioactive substances display potent antioxidant, antimicrobial, anti-inflammatory, and anti-tumoral activities, and therefore represent key-compounds in preventing various diseases (e.g. cancer, chronic inflammation, atherosclerosis and cardiovascular disorder) and ageing processes. The ongoing research will lead to the utilisation of halophytes as a new source of healthy products as functional foods, nutraceuticals or active principles in several industries. This contribution focuses on the ethnopharmacological uses of halophytes in traditional medicine and reviews recent investigations on their biological activities and nutraceuticals. The work is distributed according to the different families of nutraceuticals (lipids, vitamins, proteins, glycosides, phenolic compounds, etc.) discussing the analytical techniques employed for their determination. Information about the claimed health promoting effects of the different families of nutraceuticals is also provided together with data on their application.
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Remeur, Camille; Le Borgne, Erell; Gauthier, Léa; Grougnet, Raphaël; Deguin, Brigitte; Poullain, Cyril; Litaudon, Marc
2017-05-01
Iridoid glycosides possess highly functionalised monoterpenoid aglycon with several contiguous stereocentres. For the most common, they are often present in quantities reaching several percentage of the fresh plant weight, and thus they may be regarded as starting material for the synthesis of a number of new chiral and bioactive molecules. To quantify and to isolate 8-O-acetylharpagide (AH) from several extracts of Oxera coronata R.P.J. de Kok, a Lamiaceae species endemic to New Caledonia, using HPLC-ELSD (evaporative light scattering detector) and centrifugal partition chromatography (CPC). Oxera coronata produces high amounts of AH in leaves, twigs and fruits. Water and methanol extracts of these plant parts were prepared. The content of AH in each extract was quantified by HPLC-ELSD, using acetonitrile-water (+0.1% formic acid) gradient elution. The HPLC method was validated for precision, linearity, limit of detection (LOD), limit of quantification (LOQ) and accuracy. A ternary solvent system ethyl acetate/n-propanol/water (3:2:5, v/v/v) was selected and applied to recover the target compound using Spot CPC from the leaves aqueous extract. HPLC-ELSD analysis followed by CPC purification led to the efficient isolation of AH from O. coronata leaves aqueous extract. HPLC-ELSD has proven to be a well-adapted detection and quantification method for iridoid glycosides, while CPC confirmed to be an efficient technique for the isolation of polar compounds. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
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Yin, Qinggang; Shen, Guoan; Chang, Zhenzhan; Tang, Yuhong; Gao, Hongwen
2017-01-01
Abstract Flavonols are one of the largest groups of flavonoids that confer benefits for the health of plants and animals. Flavonol glycosides are the predominant flavonoids present in the model legume Lotus japonicus. The molecular mechanisms underlying the biosynthesis of flavonol glycosides as yet remain unknown in L. japonicus. In the present study, we identified a total of 188 UDP-glycosyltransferases (UGTs) in L. japonicus by genome-wide searching. Notably, 12 UGTs from the UGT72 family were distributed widely among L. japonicus chromosomes, expressed in all tissues, and showed different docking scores in an in silico bioinformatics docking analysis. Further enzymatic assays showed that five recombinant UGTs (UGT72AD1, UGT72AF1, UGT72AH1, UGT72V3, and UGT72Z2) exhibit activity toward flavonol, flavone, and isoflavone aglycones. In particular, UGT72AD1, UGT72AH1, and UGT72Z2 are flavonol-specific UGTs with different kinetic properties. In addition, the overexpression of UGT72AD1 and UGT72Z2 led to increased accumulation of flavonol rhamnosides in L. japonicus and Arabidopsis thaliana. Moreover, the increase of kaempferol 3-O-rhamnoside-7-O-rhamnoside in transgenic A. thaliana inhibited root growth as compared with the wild-type control. These results highlight the significance of the UGT72 family in flavonol glycosylation and the role of flavonol rhamnosides in plant growth. PMID:28204516
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Kaltner, Herbert; Szabó, Tamás; Fehér, Krisztina; André, Sabine; Balla, Sára; Manning, Joachim C; Szilágyi, László; Gabius, Hans-Joachim
2017-06-15
The emerging significance of recognition of cellular glycans by lectins for diverse aspects of pathophysiology is a strong incentive for considering development of bioactive and non-hydrolyzable glycoside derivatives, for example by introducing S/Se atoms and the disulfide group instead of oxygen into the glycosidic linkage. We report the synthesis of 12 bivalent thio-, disulfido- and selenoglycosides attached to benzene/naphthalene cores. They present galactose, for blocking a plant toxin, or lactose, the canonical ligand of adhesion/growth-regulatory galectins. Modeling reveals unrestrained flexibility and inter-headgroup distances too small to bridge two sites in the same lectin. Inhibitory activity was first detected by solid-phase assays using a surface-presented glycoprotein, with relative activity enhancements per sugar unit relative to free cognate sugar up to nearly 10fold. Inhibitory activity was also seen on lectin binding to surfaces of human carcinoma cells. In order to proceed to characterize this capacity in the tissue context monitoring of lectin binding in the presence of inhibitors was extended to sections of three types of murine organs as models. This procedure proved to be well-suited to determine relative activity levels of the glycocompounds to block binding of the toxin and different human galectins to natural glycoconjugates at different sites in sections. The results on most effective inhibition by two naphthalene-based disulfides and a selenide raise the perspective for broad applicability of the histochemical assay in testing glycoclusters that target biomedically relevant lectins. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Rate of hydrolysis and degradation of the cyanogenic glycoside - dhurrin - in soil.
Johansen, Henrik; Rasmussen, Lars Holm; Olsen, Carl Erik; Bruun Hansen, Hans Christian
2007-02-01
Cyanogenic glycosides are common plant toxins. Toxic hydrogen cyanide originating from cyanogenic glycosides may affect soil processes and water quality. In this study, hydrolysis, degradation and sorption of dhurrin (4-hydroxymandelonitrile-beta-d-glucoside) produced by sorghum has been studied in order to assess its fate in soil. The log K(ow) of dhurrin was -1.18+/-0.08 (22 degrees C). Hydrolysis was a first-order reaction with respect to dhurrin and hydroxyl ion concentrations. Half lives ranged from 1.2h (pH 8.6; 25 degrees C) to 530d (pH 4; 25 degrees C). The activation energy of hydrolysis was 112+9kJ. At pH 5.8 and room temperature, addition of humic acids (50gl(-1)) increased the rate of hydrolysis tenfold, while addition of kaolinite or goethite (100-250gl(-1)) both decreased the rate considerably. No significant sorption to soil components could be observed. The degradation rates of dhurrin in top and subsoils of Oxisols, Ultisols, Alfisols and Mollisols were studied at 22 degrees C (25mgl(-1), soil:liquid 1:1 (w:V), pH 3.8-8.1). Half-lives were 0.25-2h for topsoils, and 5-288h in subsoils. Hydrolysis in solution explained up to 45% of the degradation in subsoils whereas the contribution in topsoils was less than 14%, indicating the importance of enzymatic degradation processes. The highest risk of dhurrin leaching will take place when the soil is a low activity acid shallow soil with low content of clay minerals, iron oxides and humic acids.
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Li, Shuxian; Musungu, Bryan; Lightfoot, David; Ji, Pingsheng
2018-01-01
Phomopsis longicolla T. W. Hobbs (syn. Diaporthe longicolla ) is the primary cause of Phomopsis seed decay (PSD) in soybean, Glycine max (L.) Merrill. This disease results in poor seed quality and is one of the most economically important seed diseases in soybean. The objectives of this study were to infer protein-protein interactions (PPI) and to identify conserved global networks and pathogenicity subnetworks in P. longicolla including orthologous pathways for cell signaling and pathogenesis. The interlog method used in the study identified 215,255 unique PPIs among 3,868 proteins. There were 1,414 pathogenicity related genes in P. longicolla identified using the pathogen host interaction (PHI) database. Additionally, 149 plant cell wall degrading enzymes (PCWDE) were detected. The network captured five different classes of carbohydrate degrading enzymes, including the auxiliary activities, carbohydrate esterases, glycoside hydrolases, glycosyl transferases, and carbohydrate binding molecules. From the PPI analysis, novel interacting partners were determined for each of the PCWDE classes. The most predominant class of PCWDE was a group of 60 glycoside hydrolases proteins. The glycoside hydrolase subnetwork was found to be interacting with 1,442 proteins within the network and was among the largest clusters. The orthologous proteins FUS3, HOG, CYP1, SGE1, and the g5566t.1 gene identified in this study could play an important role in pathogenicity. Therefore, the P. longicolla protein interactome (PiPhom) generated in this study can lead to a better understanding of PPIs in soybean pathogens. Furthermore, the PPI may aid in targeting of genes and proteins for further studies of the pathogenicity mechanisms.
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Li, Shuxian; Musungu, Bryan; Lightfoot, David; Ji, Pingsheng
2018-01-01
Phomopsis longicolla T. W. Hobbs (syn. Diaporthe longicolla) is the primary cause of Phomopsis seed decay (PSD) in soybean, Glycine max (L.) Merrill. This disease results in poor seed quality and is one of the most economically important seed diseases in soybean. The objectives of this study were to infer protein–protein interactions (PPI) and to identify conserved global networks and pathogenicity subnetworks in P. longicolla including orthologous pathways for cell signaling and pathogenesis. The interlog method used in the study identified 215,255 unique PPIs among 3,868 proteins. There were 1,414 pathogenicity related genes in P. longicolla identified using the pathogen host interaction (PHI) database. Additionally, 149 plant cell wall degrading enzymes (PCWDE) were detected. The network captured five different classes of carbohydrate degrading enzymes, including the auxiliary activities, carbohydrate esterases, glycoside hydrolases, glycosyl transferases, and carbohydrate binding molecules. From the PPI analysis, novel interacting partners were determined for each of the PCWDE classes. The most predominant class of PCWDE was a group of 60 glycoside hydrolases proteins. The glycoside hydrolase subnetwork was found to be interacting with 1,442 proteins within the network and was among the largest clusters. The orthologous proteins FUS3, HOG, CYP1, SGE1, and the g5566t.1 gene identified in this study could play an important role in pathogenicity. Therefore, the P. longicolla protein interactome (PiPhom) generated in this study can lead to a better understanding of PPIs in soybean pathogens. Furthermore, the PPI may aid in targeting of genes and proteins for further studies of the pathogenicity mechanisms. PMID:29666630
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Vanishing flora--lost chemistry: the scents of endangered plants around the world.
Kaiser, Roman
2004-01-01
As part of our broad and ongoing evaluation of the olfactory components of fragrant plants and flowers during the past 25 years, we have encountered an astounding number of interestingly scented, but endangered plant species. In appreciation of nature's marvels in these species, we are compiling a report on their scent compositions and complementary information in an upcoming book 'Vanishing Flora--Lost Chemistry'. In this paper, a few examples of endangered plant species and their scent components are presented as a brief introduction to the concept of the book project.
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ERIC Educational Resources Information Center
South Dakota Dept. of Environmental Protection, Pierre.
Presented are basic concepts of chemistry necessary for operators who manage drinking water treatment plants and wastewater facilities. It includes discussions of chemical terms and concepts, laboratory procedures for basic analyses of interest to operators, and discussions of appropriate chemical calculations. Exercises are included and answer…
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Wenzel, Thomas J
2006-01-01
The laboratory component of a first-semester general chemistry course for science majors is described. The laboratory involves a semester-long project undertaken in a small-group format. Students are asked to examine whether plants grown in soil contaminated with lead take up more lead than those grown in uncontaminated soil. They are also asked to examine whether the acidity of the rainwater affects the amount of lead taken up by the plants. Groups are then given considerable independence in the design and implementation of the experiment. Once the seeds are planted, which takes about 4 wk into the term, several shorter experiments are integrated in before it is time to harvest and analyze the plants. The use of a project and small working groups allows for the development of a broader range of learning outcomes than occurs in a "traditional" general chemistry laboratory. The nature of these outcomes and some of the student responses to the laboratory experience are described. This particular project also works well at demonstrating the connections among chemistry, biology, geology, and environmental studies.
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Wenzel, Thomas J.
2006-01-01
The laboratory component of a first-semester general chemistry course for science majors is described. The laboratory involves a semester-long project undertaken in a small-group format. Students are asked to examine whether plants grown in soil contaminated with lead take up more lead than those grown in uncontaminated soil. They are also asked to examine whether the acidity of the rainwater affects the amount of lead taken up by the plants. Groups are then given considerable independence in the design and implementation of the experiment. Once the seeds are planted, which takes about 4 wk into the term, several shorter experiments are integrated in before it is time to harvest and analyze the plants. The use of a project and small working groups allows for the development of a broader range of learning outcomes than occurs in a “traditional” general chemistry laboratory. The nature of these outcomes and some of the student responses to the laboratory experience are described. This particular project also works well at demonstrating the connections among chemistry, biology, geology, and environmental studies. PMID:17012193
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Miao, Tianxin; Wang, Junqing; Zeng, Yun; Chen, Xiaoyuan
2018-01-01
Abstract Polysaccharides or polymeric carbohydrate molecules are long chains of monosaccharides that are linked by glycosidic bonds. The naturally based structural materials are widely applied in biomedical applications. This article covers four different types of polysaccharides (i.e., alginate, chitosan, hyaluronic acid, and dextran) and emphasizes their chemical modification, preparation approaches, preclinical studies, and clinical translations. Different cargo fabrication techniques are also presented in the third section. Recent progresses in preclinical applications are then discussed, including tissue engineering and treatment of diseases in both therapeutic and monitoring aspects. Finally, clinical translational studies with ongoing clinical trials are summarized and reviewed. The promise of new development in nanotechnology and polysaccharide chemistry helps clinical translation of polysaccharide‐based drug delivery systems. PMID:29721408
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Noncariogenic intense natural sweeteners.
Kinghorn, A D; Kaneda, N; Baek, N I; Kennelly, E J; Soejarto, D D
1998-09-01
There is a definite relationship between the dietary consumption of sucrose and the incidence of dental caries. Noncaloric sucrose substitutes for use in the sweetening of foods, beverages, and medicines may be either synthetic compounds or natural products. In the United States, four potently sweet artificial sweeteners are approved, namely, saccharin, aspartame, acesulfame potassium, and sucralose. Highly sweet plant constituents are used in Japan and some other countries, including the diterpene glycoside stevioside and the protein thaumatin. Recent progress in a research project oriented towards the discovery and evaluation of novel potentially noncariogenic sweeteners from plants has focused on substances in the sesquiterpenoid, diterpenoid, triterpenoid, steroidal saponin, and proanthocyanidin structural classes. The feasibility of using Mongolian gerbil electrophysiological and behavioral assays to monitor the sweetness of plant extracts, chromatographic fractions, and pure isolates has been investigated. An in vivo cariogenicity study on the commercially available natural sweeteners stevioside and rebaudioside A has been carried out.
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Markowski, Michał; Długosz, Marek; Szakiel, Anna; Durli, Mathieu; Poinsignon, Sophie; Bouguet-Bonnet, Sabine; Vernex-Loset, Lionel; Krier, Gabriel; Henry, Max
2018-04-18
Native plant of marigold (Calendula officinalis L.) synthesizes oleanolic acid saponins classified as glucosides or glucuronides according to the first residue in sugar chain bound to C-3 hydroxyl group. Hairy root culture, obtained by transformation with Agrobacterium rhizogenes strain 15834, exhibit a potent ability of synthesis of oleanolic acid glycosides. The HPLC profile of saponin fraction obtained from C. officinalis hairy roots treated with plant stress hormone, jasmonic acid, showed the 10-times increase of the content of one particular compound, determined by NMR and MALDI TOF as a new bisdesmoside saponin, 3-O-β-d-glucuronopyranosyl-28-O-β-d-galactopyranosyl-oleanolic acid. Such a diglycoside does not occur in native C. officinalis plant. It is a glucuronide, whereas in the native plant glucuronides are mainly accumulated in flowers, while glucosides are the most abundant saponins in roots. Thus, our results revealed that the pathways of saponin biosynthesis, particularly reactions of glycosylation, are altered in C. officinalis hairy root culture.
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Inamine, Saki; Onaga, Shoko; Ohnuma, Takayuki; Fukamizo, Tamo; Taira, Toki
2015-01-01
Chitinase-A (EaChiA), molecular mass 36 kDa, was purified from the vegetative stems of a horsetail (Equisetum arvense) using a series of column chromatography. The N-terminal amino acid sequence of EaChiA was similar to the lysin motif (LysM). A cDNA encoding EaChiA was cloned by rapid amplification of cDNA ends and polymerase chain reaction. It consisted of 1320 nucleotides and encoded an open reading frame of 361 amino acid residues. The deduced amino acid sequence indicated that EaChiA is composed of a N-terminal LysM domain and a C-terminal plant class IIIb chitinase catalytic domain, belonging to the glycoside hydrolase family 18, linked by proline-rich regions. EaChiA has strong chitin-binding activity, however, no antifungal activity. This is the first report of a chitinase from Equisetopsida, a class of fern plants, and the second report of a LysM-containing chitinase from a plant.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Hahn, Michael G.
The project seeks to investigate the mechanism by which CBMs potentiate the activity of glycoside hydrolases against complete plant cell walls. The project is based on the hypothesis that the wide range of CBMs present in bacterial enzymes maximize the potential target substrates by directing the cognate enzymes not only to different regions of a specific plant cell wall, but also increases the range of plant cell walls that can be degraded. In addition to maximizing substrate access, it was also proposed that CBMs can target specific subsets of hydrolases with complementary activities to the same region of the plantmore » cell wall, thereby maximizing the synergistic interactions between these enzymes. This synergy is based on the premise that the hydrolysis of a specific polysaccharide will increase the access of closely associated polymers to enzyme attack. In addition, it is unclear whether the catalytic module and appended CBM of modular enzymes have evolved unique complementary activities.« less
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Caecal absorption of vitexin-2-O-xyloside and its aglycone apigenin, in the rat
USDA-ARS?s Scientific Manuscript database
The in vivo bioavailability of the flavone-C-glycosides has been little studied compared to their O-glycoside analogues, which are both more common in nature and considered more easily hydrolyzed than C-glycosides, by enterocytes and gut microbiota. In this study, we used vitexin-2-O-xyloside (VOX),...
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Dong, Ping; Xue, Chang-Hu; Yu, Lin-Fang; Xu, Jie; Chen, Shi-Guo
2008-07-09
A creative and sensitive method has been developed for the determination of triterpene glycosides concentrations in sea cucumber ( Stichopus japonicus) and related products by using d-quinovose (6-deoxyglucose) as the measurement standard by reverse-phase high-performance liquid chromatography (HPLC) and variable-wavelength detection. d-quinovose, which is a unique monosaccharide in holostane triterpene glycosides, was liberated by acid hydrolysis and precolumn derivatized by 1-phenyl-3-methyl-5-pyrazolone (PMP). PMP-quinovose was analyzed by HPLC with 22% acetonitrile in 0.05 M KH2PO4 aquatic solution (pH 5.2) as mobile phase. The calibration curves of d-quinovose were linear within the range of 6.56-164 mg/L (r(2) > 0.995). The contents of triterpene glycosides in various S. japonicus products were determined after appropriate pretreatment methods. The concentration of triterpene glycosides was calculated by the formula C = C(qui) x alpha (alpha = 8.5). The result showed that this method was a simple, rapid, and stable method for the determination of triterpene glycosides in S. japonicus products.
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Zhou, Tingting; Liu, Hua; Wen, Jun; Fan, Guorong; Chai, Yifeng; Wu, Yutian
2010-09-15
A high-performance liquid chromatography-diode array detection/electrospray ionization mass spectrometry (HPLC-DAD/ESI-MS) method was applied to the characterization of ten iridoid glycosides in Gardenia jasminoides Ellis, a traditional Chinese medicine. During the process of structural elucidation, two groups of isomers including two epimers were structurally characterized and differentiated according to their distinctive fragmentation patterns which were closely related to their isomeric differentiations. Subsequently, the major compounds were purified by multi-dimensional chromatography and semi-preparative HPLC and the structure identification was confirmed with NMR techniques. The major fragmentation pathways of iridoid glycosides in Gardenia jasminoides Ellis obtained through the MS data were schemed systematically, which provided the best sensitivity and specificity for characterization of the iridoid glycosides especially the isomers so far. Based on the fragmentation patterns of iridoid glycosides concluded, seven major iridoid glycosides were characterized in rat plasma after intravenous administration of Gardenia jasminoides Ellis. Copyright 2010 John Wiley & Sons, Ltd.
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Bursać Kovačević, Danijela; Barba, Francisco J; Granato, Daniel; Galanakis, Charis M; Herceg, Zoran; Dragović-Uzelac, Verica; Putnik, Predrag
2018-07-15
Stevia rebaudiana Bertoni leaves are a natural source of diterpenic glycosides, and various bioactive compounds. The objectives were to characterize antioxidants and steviol glycosides in the extracts obtained from Stevia after "green" pressurized hot water extraction (PHWE). PHWE extracts were obtained at different temperatures (100, 130, 160 °C); static extraction times (5 and 10 min), and cycle numbers (1, 2, 3) using a constant pressure of 10.34 MPa. Temperature was the most important parameter for extraction, where the highest recoveries of all bioactive compounds (except for carotenoids) were at 160 °C. Extracts obtained at longer static times had more steviol glycosides, condensed tannins, and chlorophyll A. Higher amounts of total phenols, condensed tannins, and steviol glycosides were obtained under higher cycle numbers. This study indicated that PHWE is useful for recovering polar and nonpolar antioxidants and steviol glycosides. PHWE may be a suitable technique for scale-up to industrial applications. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Advances in the biotechnological glycosylation of valuable flavonoids.
Xiao, Jianbo; Muzashvili, Tamar S; Georgiev, Milen I
2014-11-01
The natural flavonoids, especially their glycosides, are the most abundant polyphenols in foods and have diverse bioactivities. The biotransformation of flavonoid aglycones into their glycosides is vital in flavonoid biosynthesis. The main biological strategies that have been used to achieve flavonoid glycosylation in the laboratory involve metabolic pathway engineering and microbial biotransformation. In this review, we summarize the existing knowledge on the production and biotransformation of flavonoid glycosides using biotechnology, as well as the impact of glycosylation on flavonoid bioactivity. Uridine diphosphate glycosyltransferases play key roles in decorating flavonoids with sugars. Modern metabolic engineering and proteomic tools have been used in an integrated fashion to generate numerous structurally diverse flavonoid glycosides. In vitro, enzymatic glycosylation tends to preferentially generate flavonoid 3- and 7-O-glucosides; microorganisms typically convert flavonoids into their 7-O-glycosides and will produce 3-O-glycosides if supplied with flavonoid substrates having a hydroxyl group at the C-3 position. In general, O-glycosylation reduces flavonoid bioactivity. However, C-glycosylation can enhance some of the benefits of flavonoids on human health, including their antioxidant and anti-diabetic potential. Copyright © 2014 Elsevier Inc. All rights reserved.
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Komarnytsky, Slavko; Esposito, Debora; Rathinasabapathy, Thirumurugan; Poulev, Alexander; Raskin, Ilya
2013-01-01
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
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Komarnytsky, Slavko; Esposito, Debora; Rathinasabapathy, Thirumurugan; Poulev, Alexander; Raskin, Ilya
2013-02-27
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.
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Kuwabara, Chikako; Kasuga, Jun; Wang, Donghui; Fukushi, Yukiharu; Arakawa, Keita; Koyama, Toshie; Inada, Takaaki; Fujikawa, Seizo
2011-12-01
Deep supercooling xylem parenchyma cells (XPCs) in Katsura tree contain flavonol glycosides with high supercooling-facilitating capability in solutions containing the ice nucleation bacterium (INB) Erwinia ananas, which is thought to have an important role in deep supercooling of XPCs. The present study, in order to further clarify the roles of these flavonol glycosides in deep supercooling of XPCs, the effects of these supercooling-facilitating (anti-ice nucleating) flavonol glycosides, kaempferol 3-O-β-D-glucopyranoside (K3Glc), kaempferol 7-O-β-D-glucopyranoside (K7Glc) and quercetin 3-O-β-D-glucopyranoside (Q3Glc), in buffered Milli-Q water (BMQW) containing different kinds of ice nucleators, including INB Xanthomonas campestris, silver iodide and phloroglucinol, were examined by a droplet freezing assay. The results showed that all of the flavonol glycosides promoted supercooling in all solutions containing different kinds of ice nucleators, although the magnitudes of supercooling capability of each flavonol glycoside changed in solutions containing different kinds of ice nucleators. On the other hand, these flavonol glycosides exhibited complicated nucleating reactions in BMQW, which did not contain identified ice nucleators but contained only unidentified airborne impurities. Q3Glc exhibited both supercooling-facilitating and ice nucleating capabilities depending on the concentrations in such water. Both K3Glc and K7Glc exhibited only ice nucleation capability in such water. It was also shown by an emulsion freezing assay in BMQW that K3Glc and Q3Glc had no effect on homogeneous ice nucleation temperature, whereas K7Glc increased ice nucleation temperature. The results indicated that each flavonol glycoside affected ice nucleation by very complicated and varied reactions. More studies are necessary to determine the exact roles of these flavonol glycosides in deep supercooling of XPCs in which unidentified heterogeneous ice nucleators may exist. Copyright © 2011 Elsevier Inc. All rights reserved.
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Cao, Jie; Yin, Chengle; Qin, Yan; Cheng, Zhihong; Chen, Daofeng
2014-10-01
The mass spectrometric (MS) analysis of flavone di-C-glycosides has been a difficult task due to pure standards being unavailable commercially and to that the reported relative intensities of some diagnostic ions varied with MS instruments. In this study, five flavone di-C-glycoside standards from Viola yedoensis have been systematically studied by high performance liquid chromatography-electrospray ionization-tandem ion trap mass spectrometry (HPLC-ESI-IT-MS(n)) in the negative ion mode to analyze their fragmentation patterns. A new MS(2) and MS(3) hierarchical fragmentation for the identification of the sugar nature (hexoses or pentoses) at C-6 and C-8 is presented based on previously established rules of fragmentation. Here, for the first time, we report that the MS(2) and MS(3) structure-diagnostic fragments about the glycosylation types and positions are highly dependent on the configuration of the sugars at C-6 and C-8. The base peak ((0,2) X1 (0,2) X(2)(-) ion) in MS(3) spectra of di-C-glycosides could be used as a diagnostic ion for flavone aglycones. These newly proposed fragmentation behaviors have been successfully applied to the characterization of flavone di-C-glycosides found in V. yedoensis. A total of 35 flavonoid glycosides, including 1 flavone mono-C-hexoside, 2 flavone 6,8-di-C-hexosides, 11 flavone 6,8-di-C-pentosides, 13 flavone 6,8-C-hexosyl-C-pentosides, 5 acetylated flavone C-glycosides and 3 flavonol O-glycosides, were identified or tentatively identified on the base of their UV profiles, MS and MS(n) (n = 5) data, or by comparing with reference substances. Among these, the acetylated flavone C-glycosides were reported from V. yedoensis for the first time. Copyright © 2014 John Wiley & Sons, Ltd.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Esquerre-Tugaye, M.T.; Lamport, D.T.A.
1979-08-01
Infection of muskmelon Cucumis melo seedlings by the fungus Colletotrichum lagenarium causes a 10-fold increase in the amount of cell wall hydroxyproline-rich glycoprotein. Evidence for this increase was provided by studying two specific markers of this glycoprotein, namely hydroxyproline and glycosylated serine. The lability of the O-glycosidic linkage of wall-bound glycosylated serine in the presence of hydrazine was used to determine the amount of serine which is glycosylated. A large increase in the hydroxyproline content of infected plants is shown, but the ratios of glycosylated serine to hydroxyproline are similar in healthy and infected plants. As far as these markersmore » are concerned, the hydroxyproline-rich glycoproteins secreted into the wall as a result of the disease are similar to those of healthy plants. In addition, the extent of glycosylation of the wall serine, in both healthy and infected plants, decreases as the plant ages. Serine- and hydroxyproline-rich (glyco)peptides were also isolated after trypsinolysis of the wall. These (glyco)peptides include the galactosyl-containing pentapeptide, serine-hydroxyproline. This pentapeptide is characteristic of cell wall protein.« less
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Pharmacological and Ethnomedicinal Overview of Heritiera fomes: Future Prospects
Islam, Md Khirul; Barman, Apurba Kumar; Rahman, Md Mustafizur; Rahman, Taufiq; Al-Nahain, Abdullah; Jahan, Rownak
2014-01-01
Mangrove plants are specialized woody plants growing in the swamps of tidal-coastal areas and river deltas of tropical and subtropical parts of the world. They have been utilized for medicinal and other purposes by the coastal people over the years. Heritiera fomes Buch. Ham. (family: Sterculiaceae) commonly known as Sundari (Bengali) is a preeminent mangrove plant occurring in the Sundarbans forest located in the southern part of Bangladesh and adjoining West Bengal province of India. The plant has applications in traditional folk medicine as evidenced by its extensive use for treating diabetes, hepatic disorders, gastrointestinal disorders, goiter, and skin diseases by the local people and traditional health practitioners. A number of investigations indicated that the plant possesses significant antioxidant, antinociceptive, antihyperglycemic, antimicrobial, and anticancer activities. Phytochemical analyses have revealed the presence of important chemical constituents like saponins, alkaloids, glycosides, tannins, steroids, flavonoids, gums, phytosterols, and reducing sugars. The present study is aimed at compiling information on phytochemical, biological, pharmacological, and ethnobotanical properties of this important medicinal plant, with a view to critically assess the legitimacy of the use of this plant in the aforementioned disorders as well as providing directions for further research. PMID:27382611
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Sugimoto, Koichi; Matsui, Kenji; Iijima, Yoko; Akakabe, Yoshihiko; Muramoto, Shoko; Ozawa, Rika; Uefune, Masayoshi; Sasaki, Ryosuke; Alamgir, Kabir Md.; Akitake, Shota; Nobuke, Tatsunori; Galis, Ivan; Aoki, Koh; Shibata, Daisuke; Takabayashi, Junji
2014-01-01
Plants receive volatile compounds emitted by neighboring plants that are infested by herbivores, and consequently the receiver plants begin to defend against forthcoming herbivory. However, to date, how plants receive volatiles and, consequently, how they fortify their defenses, is largely unknown. In this study, we found that undamaged tomato plants exposed to volatiles emitted by conspecifics infested with common cutworms (exposed plants) became more defensive against the larvae than those exposed to volatiles from uninfested conspecifics (control plants) in a constant airflow system under laboratory conditions. Comprehensive metabolite analyses showed that only the amount of (Z)-3-hexenylvicianoside (HexVic) was higher in exposed than control plants. This compound negatively affected the performance of common cutworms when added to an artificial diet. The aglycon of HexVic, (Z)-3-hexenol, was obtained from neighboring infested plants via the air. The amount of jasmonates (JAs) was not higher in exposed plants, and HexVic biosynthesis was independent of JA signaling. The use of (Z)-3-hexenol from neighboring damaged conspecifics for HexVic biosynthesis in exposed plants was also observed in an experimental field, indicating that (Z)-3-hexenol intake occurred even under fluctuating environmental conditions. Specific use of airborne (Z)-3-hexenol to form HexVic in undamaged tomato plants reveals a previously unidentified mechanism of plant defense. PMID:24778218
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18. VIEW OF THE GENERAL CHEMISTRY LAB. THE LABORATORY PROVIDED ...
18. VIEW OF THE GENERAL CHEMISTRY LAB. THE LABORATORY PROVIDED GENERAL ANALYTICAL AND STANDARDS CALIBRATION, AS WELL AS DEVELOPMENT OPERATIONS INCLUDING WASTE TECHNOLOGY DEVELOPMENT AND DEVELOPMENT AND TESTING OF MECHANICAL SYSTEMS FOR WEAPONS SYSTEMS. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO
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Zen, Federico; Angione, M. Daniela; Behan, James A.; Cullen, Ronan J.; Duff, Thomas; Vasconcelos, Joana M.; Scanlan, Eoin M.; Colavita, Paula E.
2016-01-01
Carbon materials and nanomaterials are of great interest for biological applications such as implantable devices and nanoparticle vectors, however, to realize their potential it is critical to control formation and composition of the protein corona in biological media. In this work, protein adsorption studies were carried out at carbon surfaces functionalized with aryldiazonium layers bearing mono- and di-saccharide glycosides. Surface IR reflectance absorption spectroscopy and quartz crystal microbalance were used to study adsorption of albumin, lysozyme and fibrinogen. Protein adsorption was found to decrease by 30–90% with respect to bare carbon surfaces; notably, enhanced rejection was observed in the case of the tested di-saccharide vs. simple mono-saccharides for near-physiological protein concentration values. ζ-potential measurements revealed that aryldiazonium chemistry results in the immobilization of phenylglycosides without a change in surface charge density, which is known to be important for protein adsorption. Multisolvent contact angle measurements were used to calculate surface free energy and acid-base polar components of bare and modified surfaces based on the van Oss-Chaudhury-Good model: results indicate that protein resistance in these phenylglycoside layers correlates positively with wetting behavior and Lewis basicity. PMID:27108562
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Symbiotic bacteria enable olive fly larvae to overcome host defences
Ben-Yosef, Michael; Pasternak, Zohar; Jurkevitch, Edouard; Yuval, Boaz
2015-01-01
Ripe fruit offer readily available nutrients for many animals, including fruit fly larvae (Diptera: Tephritidae) and their associated rot-inducing bacteria. Yet, during most of their ontogeny, fruit remain chemically defended and effectively suppress herbivores and pathogens by high levels of secondary metabolites. Olive flies (Bactrocera oleae) are uniquely able to develop in unripe olives. Unlike other frugivorous tephritids, the larvae maintain bacteria confined within their midgut caeca. We examined the interaction between larvae, their associated bacteria, and fruit chemical defence, hypothesizing that bacterial contribution to larval development is contingent on the phenology of fruit defensive chemistry. We demonstrate that larvae require their natural complement of bacteria (Candidatus Erwinia dacicola: Enterobacteriaceae) in order to develop in unripe olives. Conversely, when feeding on ripe fruit, larval development proceeds independently of these bacteria. Our experiments suggest that bacteria counteract the inhibitory effect of oleuropein—the principal phenolic glycoside in unripe olives. In light of these results, we suggest that the unique symbiosis in olive flies, compared with other frugivorous tephritids, is understood by considering the relationship between the fly, bacteria and fruit chemistry. When applied in an evolutionary context, this approach may also point out the forces which shaped symbioses across the Tephritidae. PMID:26587275
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NASA Astrophysics Data System (ADS)
Zen, Federico; Angione, M. Daniela; Behan, James A.; Cullen, Ronan J.; Duff, Thomas; Vasconcelos, Joana M.; Scanlan, Eoin M.; Colavita, Paula E.
2016-04-01
Carbon materials and nanomaterials are of great interest for biological applications such as implantable devices and nanoparticle vectors, however, to realize their potential it is critical to control formation and composition of the protein corona in biological media. In this work, protein adsorption studies were carried out at carbon surfaces functionalized with aryldiazonium layers bearing mono- and di-saccharide glycosides. Surface IR reflectance absorption spectroscopy and quartz crystal microbalance were used to study adsorption of albumin, lysozyme and fibrinogen. Protein adsorption was found to decrease by 30-90% with respect to bare carbon surfaces; notably, enhanced rejection was observed in the case of the tested di-saccharide vs. simple mono-saccharides for near-physiological protein concentration values. ζ-potential measurements revealed that aryldiazonium chemistry results in the immobilization of phenylglycosides without a change in surface charge density, which is known to be important for protein adsorption. Multisolvent contact angle measurements were used to calculate surface free energy and acid-base polar components of bare and modified surfaces based on the van Oss-Chaudhury-Good model: results indicate that protein resistance in these phenylglycoside layers correlates positively with wetting behavior and Lewis basicity.
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New megastigmane glycoside and aromadendrane derivative from the aerial part of Piper elongatum.
Masuoka, Chikako; Ono, Masateru; Ito, Yasuyuki; Okawa, Masafumi; Nohara, Toshihiro
2002-10-01
A new megastigmane glycoside, called pipeloside A, and a new aromadendrane type sesquiterpenoid, pipelol A, were isolated from the MeOH extract of the aerial part of Piper elongatum VAHL. along with a known megastigmane glycoside, byzantionoside B. The structures of these compounds were elucidated on the basis of spectroscopic data and chemical evidence.
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Steroidal glycosides from the roots of Asclepias curassavica.
Warashina, Tsutomu; Noro, Tadataka
2008-03-01
Twenty-six new acylated-oxypregnane glycosides were obtained along with three known cardenolide glycosides from the roots of Asclepias curassavica (Asclepiadaceae). The new compounds were confirmed to contain 12-O-benzoylsarcostin, 12-O-benzoyldeacylmetaplexigenin, kidjolanin, and 12-O-benzoyltayloron, and one new acylated-oxypregnane, 12-O-(E)-cinnamoyltayloron, as their aglycones, using both spectroscopic and chemical methods.
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NASA Astrophysics Data System (ADS)
Dyachenko, F. V.; Petrova, T. I.
2017-11-01
Efficiency and reliability of the equipment in fossil power plants as well as in combined cycle power plants depend on the corrosion processes and deposit formation in steam/water circuit. In order to decrease these processes different water chemistries are used. Today the great attention is being attracted to the application of film forming amines and film forming amine products. The International Association for the Properties of Water and Steam (IAPWS) consolidated the information from all over the World, and based on the research studies and operating experience of researchers and engineers from 21 countries, developed and authorized the Technical Guidance Document: “Application of Film Forming Amines in Fossil, Combined Cycle, and Biomass Power Plants” in 2016. This article describe Russian and International technical guidance documents for the cycle water chemistries based on film forming amines at fossil and combined cycle power plants.
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Daayf, F.; Schmitt, A.; Belanger, R. R.
1997-03-01
Phenolic compounds extracted from cucumber (Cucumis sativus L.) leaves were separated and analyzed for their differential presence and fungitoxicity in relation to a prophylactic treatment with Milsana (Compo, Munster, Germany) against powdery mildew (Sphaerotheca fuliginea). Based on our extraction and purification procedures, at least eight separate phenolic compounds with antifungal activity were identified as intrinsic components of cucumber plants. Of these compounds, six displayed a significant increase in concentration as a result of elicitation with Milsana, this being particularly evident when the plant was stressed by the pathogen. The combined amounts of these antifungal compounds in treated plants was nearly five times the level found in control plants. One week after Milsana application, some of the antifungal compounds obtained through hydrolysis of their glycosidic links were also detected in their free form, indicating that they are likely liberated from conjugated phenolics by enzymatic hydrolysis in planta. To our knowledge, these results provide the first direct evidence that cucumber plants produce elevated levels of phytoalexins in response to an eliciting treatment after infection.
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Daayf, F.; Schmitt, A.; Belanger, R. R.
1997-01-01
Phenolic compounds extracted from cucumber (Cucumis sativus L.) leaves were separated and analyzed for their differential presence and fungitoxicity in relation to a prophylactic treatment with Milsana (Compo, Munster, Germany) against powdery mildew (Sphaerotheca fuliginea). Based on our extraction and purification procedures, at least eight separate phenolic compounds with antifungal activity were identified as intrinsic components of cucumber plants. Of these compounds, six displayed a significant increase in concentration as a result of elicitation with Milsana, this being particularly evident when the plant was stressed by the pathogen. The combined amounts of these antifungal compounds in treated plants was nearly five times the level found in control plants. One week after Milsana application, some of the antifungal compounds obtained through hydrolysis of their glycosidic links were also detected in their free form, indicating that they are likely liberated from conjugated phenolics by enzymatic hydrolysis in planta. To our knowledge, these results provide the first direct evidence that cucumber plants produce elevated levels of phytoalexins in response to an eliciting treatment after infection. PMID:12223638
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Morikawa, Toshio; Xie, Haihui; Wang, Tao; Matsuda, Hisashi; Yoshikawa, Masayuki
2008-10-01
From the methanolic extract of the whole plant of Sinocrassula indica (Crassulaceae), six new flavonol glycosides, sinocrassosides B(4) (1), B(5) (2), C(1) (3), D(1) (4), D(2) (5), and D(3) (6), were isolated together with 30 compounds. The structures of 1-6 were elucidated on the basis of chemical and physicochemical evidence. In addition, several constituents were found to show inhibitory effects on aminopeptidase N and aldose reductase.
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Force-field parameters of the Psi and Phi around glycosidic bonds to oxygen and sulfur atoms.
Saito, Minoru; Okazaki, Isao
2009-12-01
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. (c) 2009 Wiley Periodicals, Inc.
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Gregg, Katie J; Suits, Michael D L; Deng, Lehua; Vocadlo, David J; Boraston, Alisdair B
2015-10-16
O-Linked glycosylation is one of the most abundant post-translational modifications of proteins. Within the secretory pathway of higher eukaryotes, the core of these glycans is frequently an N-acetylgalactosamine residue that is α-linked to serine or threonine residues. Glycoside hydrolases in family 101 are presently the only known enzymes to be able to hydrolyze this glycosidic linkage. Here we determine the high-resolution structures of the catalytic domain comprising a fragment of GH101 from Streptococcus pneumoniae TIGR4, SpGH101, in the absence of carbohydrate, and in complex with reaction products, inhibitor, and substrate analogues. Upon substrate binding, a tryptophan lid (residues 724-WNW-726) closes on the substrate. The closing of this lid fully engages the substrate in the active site with Asp-764 positioned directly beneath C1 of the sugar residue bound within the -1 subsite, consistent with its proposed role as the catalytic nucleophile. In all of the bound forms of the enzyme, however, the proposed catalytic acid/base residue was found to be too distant from the glycosidic oxygen (>4.3 Å) to serve directly as a general catalytic acid/base residue and thereby facilitate cleavage of the glycosidic bond. These same complexes, however, revealed a structurally conserved water molecule positioned between the catalytic acid/base and the glycosidic oxygen. On the basis of these structural observations we propose a new variation of the retaining glycoside hydrolase mechanism wherein the intervening water molecule enables a Grotthuss proton shuttle between Glu-796 and the glycosidic oxygen, permitting this residue to serve as the general acid/base catalytic residue. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
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Upreti, Mani; Strassburger, Ken; Chen, You L.; Wu, Shaoxiong; Prakash, Indra
2011-01-01
Steviol glycosidesrebaudioside (reb) A, C and D have low aqueous solubilities. To improve their aqueous solubilities, inclusion complex of steviol glycosides, reb A, C and D and gamma cyclodextrin were prepared by freeze drying method and further characterized by means of differential scanning calorimetry, Fourier transform infrared spectroscopy and Raman spectroscopy. The effect of gamma cyclodextrin on chemical shifts of the steviol glycosides was also studied in proton NMR experiments as well as in solid state 13C CP/MAS NMR experiments. These results indicated that the steviol glycosides were clearly in inclusion complex formation with the gamma cyclodextrin which also results in solubility enhancement of these steviol glycosides. Phase solubility studies showed that amounts of soluble reb A, C and D increased with increasing amounts of gamma cyclodextrin indicating formation of 1:1 stoichiometric and higher order inclusion complexes. PMID:22174615
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kinney, K.K.; Lindroth, R.L.; Jung, S.M.
1997-01-01
Increasing concentrations of atmospheric CO{sub 2} will interact with other environmental factors to influence the physiology and ecology of trees. This research evaluated how plant phytochemical responses to enriched atmospheric CO{sub 2} are affected by the availability of soil nitrate (NO{sub 3}{sup -}) and how these chemical changes alter performance of a tree-feeding folivore. Seedlings of three deciduous tree species were grown in ambient or elevated CO{sub 2} in combination with low or high soil NO{sub 3}{sup -} availability. Lymantria dispar larvae were reared on foliage (aspen and maple). Concentrations of nitrogen and soluble protein decreased, whereas concentrations of starch,more » condensed tannins, and ellagitannins increased, in response to elevated CO{sub 2} and/or low NO{sub 3}{sup -}. Responses of simple carbohydrates and phenolic glycosides were variable absolute (net) changes in foliar C:N ratios were greatest for aspen and least for oak, whereas relative changes were greatest for maple and least for aspen. Elevated CO{sub 2} treatments had little effect on gypsy moth development time, growth rate, or larval mass. Larvae reared on aspen foliage grown under elevated CO{sub 2} exhibited increased consumption but decreased conversion efficiencies. Gypsy moth responses to NO{sub 3}{sup -} were strongly host specific. The magnitude of insect response elicited by resource-mediated shifts in host chemistry will depend on how levels of compounds with specific importance to insect fitness are affected. Relatively few true interactions occured between carbon and nitrogen availability and insect performance. Tree species frequently interacted with CO{sub 2} and/or NO{sub 3}{sup -} availability to affect both parameters. The effects of elevated atmospheric CO{sub 2} on terrestrial plant communities will depend on species composition and soil nutrient availability. 54 refs., 9 figs., 4 tabs.« less
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Chemical Diversity and Defence Metabolism: How Plants Cope with Pathogens and Ozone Pollution
Iriti, Marcello; Faoro, Franco
2009-01-01
Chemical defences represent a main trait of the plant innate immune system. Besides regulating the relationship between plants and their ecosystems, phytochemicals are involved both in resistance against pathogens and in tolerance towards abiotic stresses, such as atmospheric pollution. Plant defence metabolites arise from the main secondary metabolic routes, the phenylpropanoid, the isoprenoid and the alkaloid pathways. In plants, antibiotic compounds can be both preformed (phytoanticipins) and inducible (phytoalexins), the former including saponins, cyanogenic glycosides and glucosinolates. Chronic exposure to tropospheric ozone (O3) stimulates the carbon fluxes from the primary to the secondary metabolic pathways to a great extent, inducing a shift of the available resources in favour of the synthesis of secondary products. In some cases, the plant defence responses against pathogens and environmental pollutants may overlap, leading to the unspecific synthesis of similar molecules, such as phenylpropanoids. Exposure to ozone can also modify the pattern of biogenic volatile organic compounds (BVOC), emitted from plant in response to herbivore feeding, thus altering the tritrophic interaction among plant, phytophagy and their natural enemies. Finally, the synthesis of ethylene and polyamines can be regulated by ozone at level of S-adenosylmethionine (SAM), the biosynthetic precursor of both classes of hormones, which can, therefore, mutually inhibit their own biosynthesis with consequence on plant phenotype. PMID:20111684
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Development and Evaluation of a Reactive-Dispersive Plume Model: TexAQS II 2006 Case Study
NASA Astrophysics Data System (ADS)
Kim, Yong Hoon; Kim, Hyun Soo; Song, Chul Han
2015-04-01
We describe the development and evaluation of a reactive-dispersive plume model (RDPM) that combines a photo-chemistry model with a plume dilution driven by turbulent dispersion of a power-plant plume. The plume transport and turbulent dispersion are derived from a Gaussian plume model and the plume chemistry model uses 71 HxOy-NxOy-CH4 chemistry-related reactions and 184 NMHC-related reactions. Emissions from large-scale point sources have continuously increased due to the rapid industrial growth. To extensively understand and assess atmospheric impacts of the power-plant emissions, a general RDPM was applied to simultaneously simulate the dynamics and photo-chemistry of the Texas power-plant plumes. During the second Texas Air Quality Study 2006 (TexAQS II 2006) on 16 September 2006, pollutant concentrations were measured by NOAA WP-3D aircraft with successive transects across power-plant plumes in Texas, USA. The simulation performances of the RDPM were evaluated by a comparison study, using the observation data obtained from the measurements of a NOAA WP-3D flight during TexAQS II 2006 airborne field campaign. On 16 September, the WP-3D aircraft observed mainly meteorological parameters and particulate species concentrations, traversing the Monticello and Welsh power-plant plumes four times from transects A to D. In addition, some meteorological variables in an initial condition for model simulation were obtained from the Weather Research and Forecasting (WRF) model output for the specific objects. These power-plant plume cases were selected in this study, because a large number of nitrogen oxides and sulfur dioxide concentrations inside the power-plant plumes were measured without any interruption of other emission sources. For the Monticello and Welsh power-plant plumes, the model-predicted concentrations showed good agreements with the observed concentrations of ambient species (e.g., nitrogen oxides, ozone, sulfur dioxide, etc.) at the four transects. Based on these RDPM results, the power-plant plume chemistry and its possible impacts on atmospheric environments were also analyzed.
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Phenolic glycosides from sugar maple (Acer saccharum) bark.
Yuan, Tao; Wan, Chunpeng; González-Sarrías, Antonio; Kandhi, Vamsikrishna; Cech, Nadja B; Seeram, Navindra P
2011-11-28
Four new phenolic glycosides, saccharumosides A-D (1-4), along with eight known phenolic glycosides, were isolated from the bark of sugar maple (Acer saccharum). The structures of 1-4 were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for cytotoxicity effects against human colon tumorigenic (HCT-116 and Caco-2) and nontumorigenic (CCD-18Co) cell lines.
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Phytosterol glycosides reduce cholesterol absorption in humans
Lin, Xiaobo; Ma, Lina; Racette, Susan B.; Anderson Spearie, Catherine L.; Ostlund, Richard E.
2009-01-01
Dietary phytosterols inhibit intestinal cholesterol absorption and regulate whole body cholesterol excretion and balance. However, they are biochemically heterogeneous and a portion is glycosylated in some foods with unknown effects on biological activity. We tested the hypothesis that phytosterol glycosides reduce cholesterol absorption in humans. Phytosterol glycosides were extracted and purified from soy lecithin in a novel two-step process. Cholesterol absorption was measured in a series of three single-meal tests given at intervals of 2 wk to each of 11 healthy subjects. In a randomized crossover design, participants received ∼300 mg of added phytosterols in the form of phytosterol glycosides or phytosterol esters, or placebo in a test breakfast also containing 30 mg cholesterol-d7. Cholesterol absorption was estimated by mass spectrometry of plasma cholesterol-d7 enrichment 4–5 days after each test. Compared with the placebo test, phytosterol glycosides reduced cholesterol absorption by 37.6 ± 4.8% (P < 0.0001) and phytosterol esters 30.6 ± 3.9% (P = 0.0001). These results suggest that natural phytosterol glycosides purified from lecithin are bioactive in humans and should be included in methods of phytosterol analysis and tables of food phytosterol content. PMID:19246636
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Carakostas, M C; Curry, L L; Boileau, A C; Brusick, D J
2008-07-01
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 papers reporting results of research studies and reviews has been compiled in this Supplement to definitively answer unresolved questions. Specifically, recently completed studies on the general and reproductive toxicity of rebaudioside A corroborate studies carried out with purified steviol glycosides demonstrating safety at high dietary intake levels. Comparative metabolism studies provide further affirmation of the common metabolic pathway for all steviol glycosides and the common metabolism between rats and humans. Finally, clinical studies provide further evidence that purified rebaudioside A has no effect on either blood pressure or glucose homeostasis. This paper summarizes the information used to conclude that high purity rebaudioside A (rebiana) produced to food-grade specifications and according to Good Manufacturing Practices is safe for human consumption under its intended conditions of use as a general purpose sweetener.
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Thermal degradation of onion quercetin glucosides under roasting conditions.
Rohn, Sascha; Buchner, Nadja; Driemel, Gregor; Rauser, Morten; Kroh, Lothar W
2007-02-21
Flavonoids are an important constituent of the human diet. In recent years, they have gained much attention due to their physiological properties, leading to an enormous increase in research on cancer prevention and reduction of cardiovascular diseases. Unfortunately, there is limited information about the fate of flavonoid glycosides during thermal treatment such as cooking, frying, roasting, etc. Such processing techniques may have an impact on the flavonoid structure, resulting in changes of the bioavailability and activity of the flavonoids. In this study, the stability of selected model and onion quercetin glycosides under roasting conditions (180 degrees C) was determined. The influence of the kind and position of the sugar moiety was investigated. As onions contain large amounts of quercetin glycosides and are often subject to thermal processes in food production, their major glycosides were isolated using counter current chromatography and roasted. The thermal treatment led to a degradation of the quercetin glycosides. The main product is the aglycone quercetin, which remained stable during further roasting. During the roasting process of the quercetin diglucoside isolated from onion, the formation of a monoglycoside as an intermediate product was observed. This underlined that the stability of the glycosides is dependent on the kind and position of the sugar moiety.
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Alberti, Ágnes; Béni, Szabolcs; Lackó, Erzsébet; Riba, Pál; Al-Khrasani, Mahmoud; Kéry, Ágnes
2012-11-01
Sempervivum tectorum L. (houseleek) leaf juice has been known as a traditional herbal remedy. The aim of the present study was the chemical characterization of its phenolic compounds and to develop quantitation methods for its main flavonol glycoside, as well as to evaluate its antinociceptive activity. Lyophilized houseleek leaf juice was studied by HPLC-DAD coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to identify flavonol glycosides, hydroxy-benzoic and hydroxy-cinnamic acids. Ten flavonol glycosides and sixteen phenolic acid compounds were identified or tentatively characterized. Structure of the main flavonol compound was identified by nuclear magnetic resonance spectroscopy. Three characteristic kaempferol glycosides were isolated and determined by LC-ESI-MS/MS with external calibration method, using the isolated compounds as standard. The main flavonol glycoside was also determined by HPLC-DAD. Validated HPLC-DAD and LC-ESI-MS/MS methods were developed to quantify kaempferol-3-O-rhamnosyl-glucoside-7-O-rhamnoside and two other kaempferol glycosides. Antinociceptive activity of houseleek leaf juice was investigated by writhing test of mice. Sempervivum extract significantly reduced pain in the mouse writhing test. Copyright © 2012 Elsevier B.V. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Uchida, Shunsuke; Ohsumi, Katsumi; Takashima, Yoshie
1995-03-01
Improvements of operational procedures to control water chemistry, e.g., nickel/iron control, as well as application of hardware improvements for reducing radioactive corrosion products resulted in an extremely low occupational exposure of less than 0.5 man.Sv/yr without any serious impact on the radwaste system, for BWR plants involved in the Japanese Improvement and Standardization Program. Recently, {sup 60}C radioactively in the reactor water has been increasing due to less crud fixation on the two smooth surfaces of new type high performance fuels and to the pH drop caused by chromium oxide anions released from stainless steel structures and pipings. This increasemore » must be limited by changes in water chemistry, e.g., applications of modified nickel/iron ratio control and weak alkali control. Controlled water chemistry to optimize three points, the plant radiation level and integrities of fuel and structural materials, is the primary future subject for BWR water chemistry.« less
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KOMARNYTSKY, SLAVKO; ESPOSITO, DEBORA; POULEV, ALEXANDER; RASKIN, ILYA
2013-01-01
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 11β-hydroxylase and steroid 17-alpha-monooxygenase, and weak inhibition of cytochrome P450 side chain cleavage enzyme and 21β-hydroxylase, but not 3β-hydroxysteroid dehydrogenase/isomerase. PMID:23065845
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Antunes-Ricardo, Marilena; Moreno-García, Beatriz E; Gutiérrez-Uribe, Janet A; Aráiz-Hernández, Diana; Alvarez, Mario M; Serna-Saldivar, Sergio O
2014-12-01
(OFI) contains health-promoting compounds like flavonoids, being the isorhamnetin glycosides the most abundant. We evaluated the effect of OFI extracts with different isorhamnetin glycosides against two different human colon cancer cells (HT-29 and Caco2). The extracts were obtained by alkaline hydrolysis with NaOH at 40 °C during 15, 30 or 60 min. Tri and diglycosides were the most abundant isorhamnetin glycosides, therefore these compounds were isolated to compare their cytotoxic effect with the obtained from the extracts. The OFI extracts and purified isorhamnetin glycosides were more cytotoxic against HT-29 cells than Caco2 cells. OFI-30 exhibited the lowest IC50 value against HT-29 (4.9 ± 0.5 μg/mL) and against Caco2 (8.2 ± 0.3 μg/mL). Isorhamnetin diglycosides IG5 and IG6 were more cytotoxic than pure isorhamnetin aglycone or triglycosides when they were tested in HT-29 cells. Bioluminescent analysis revealed increased activity of caspase 3/7 in OFI extracts-treated cells, particularly for the extract with the highest concentration of isorhamnetin triglycosides. Flow cytometry analysis confirmed that OFI extract and isorhamnetin glycosides induced a higher percentage of apoptosis in HT-29 than in Caco2, while isorhamnetin was more apoptotic in Caco2. This research demonstrated that glycosilation affected antiproliferative effect of pure isorhamnetin glycosides or when they are mixed with other phytochemicals in an extract obtained from OFI.
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An Update Review on the Anthelmintic Activity of Bitter Gourd, Momordica charantia
Poolperm, Sutthaya; Jiraungkoorskul, Wannee
2017-01-01
Momordica charantia (Family: Cucurbitales), as known as bitter melon or gourd, is a daily consumption as food and traditional medicinal plant in Southeast Asia and Indo-China. It has been shown to possess anticancer, antidepressant, antidiabetic, anti-inflammatory, antimicrobial, antiobesity, antioxidant, and antiulcer properties. Its common phytochemical components include alkaloids, charantin, flavonoids, glycosides, phenolics, tannins, and terpenoids. This plant is rich in various saponins including momordicin, momordin, momordicoside, karavilagenin, karaviloside, and kuguacin, all of which have been reported to contribute to its remedial properties including antibacterial, antifungal, antiviral, and antiparasitic infections. Based on established literature on the anthelmintic activity of M. charantia and possible mode of action, this review article has attempted to compile M. charantia could be further explored for the development of potential anthelmintic drug. PMID:28503051
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An Update Review on the Anthelmintic Activity of Bitter Gourd, Momordica charantia.
Poolperm, Sutthaya; Jiraungkoorskul, Wannee
2017-01-01
Momordica charantia (Family: Cucurbitales ), as known as bitter melon or gourd, is a daily consumption as food and traditional medicinal plant in Southeast Asia and Indo-China. It has been shown to possess anticancer, antidepressant, antidiabetic, anti-inflammatory, antimicrobial, antiobesity, antioxidant, and antiulcer properties. Its common phytochemical components include alkaloids, charantin, flavonoids, glycosides, phenolics, tannins, and terpenoids. This plant is rich in various saponins including momordicin, momordin, momordicoside, karavilagenin, karaviloside, and kuguacin, all of which have been reported to contribute to its remedial properties including antibacterial, antifungal, antiviral, and antiparasitic infections. Based on established literature on the anthelmintic activity of M. charantia and possible mode of action, this review article has attempted to compile M. charantia could be further explored for the development of potential anthelmintic drug.
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Tetrahydroxanthones from Mongolian medicinal plant Gentianella amarella ssp. acuta.
Lu, Shuangxin; Tanaka, Naonobu; Kawazoe, Kazuyoshi; Murakami, Kotaro; Damdinjav, Davaadagva; Dorjbal, Enkhjargal; Kashiwada, Yoshiki
2016-10-01
Two tetrahydroxanthones, 1,3,5S,8S-tetrahydroxy-5,6,7,8-tetrahydroxanthone (1) and 1,3,5R,8S-tetrahydroxy-5,6,7,8-tetrahydroxanthone (2), and six new tetrahydroxanthone glycosides, amarellins A-F (3-8), were isolated from the aerial parts of a Mongolian medicinal plant Gentianella amarella ssp. acuta (Gentianaceae). The structures of 1-8 were elucidated on the basis of spectroscopic analysis, chemical conversion, and ECD calculation. Amarellins A-C (3-5) were assigned as 8-O-β-D-glucoside, 8-O-β-D-xyloside, and 1-O-β-D-glucoside of 1, respectively, while amarellins D-F (6-8) were elucidated to be 8-O-β-D-xyloside, 1-O-β-D-glucoside, and 3-O-β-D-glucoside of 2, respectively.
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Screening of antibacterial potentials of some medicinal plants from Melghat forest in India.
Tambekar, D H; Khante, B S; Chandak, B R; Titare, A S; Boralkar, S S; Aghadte, S N
2009-05-07
Cyperus rotundus, Caesalpinia bonducella, Tinospora cordifolia, Gardenia gummifera, Ailanthus excelsa, Acacia arabica, Embelia ribes and Ventilago maderspatana from Melghat forest were screened for their antibacterial potential against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris, Salmonella typhi, Shigella flexneri, Salmonella paratyphi, Salmonella typhimurium, Pseudomonas aeruginosa, Enterobacter aerogenes by disc diffusion method. Out of these medicinal plants Caesalpinia bonducella, Gardenia gummifera and Acacia arabica showed remarkable antibacterial potential. The phytochemical analysis had showed the presence of Cardiac glycosides in all extracts (aqueous, acetone, ethanol and methanol) of Acacia arabica, Gardenia gummifera and ethanol, methanol extracts of Caesalpinia bonducella. Flavonoids were present in Gardenia gummifera, Ailanthus excelsa and acetone, methanol extracts of Acacia Arabica. Tannins and phenolic were present in Cyperus rotundus, Embelia ribes, and organic extracts of Ventilago maderspatana.
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Compositional Changes in Foliage Phenolics with Plant Age, a Natural Experiment in Boreal Forests.
Wam, Hilde Karine; Stolter, Caroline; Nybakken, Line
2017-09-01
The composition of plant secondary metabolites (PSMs) extensively impacts ecosystem functioning. It is vital that we understand temporal patterns in the plants' allocation of resources to PSMs, particularly those influenced by human activity. Existing data are insufficient in the long-term perspective of perennial plants (age or ontogeny). We analysed phenolic concentrations in foliage from birch (Betula pubescens Ehr.) considered to be undamaged and growing on 5, 10 and 15 years old clear-cuts in two boreal forest landscapes in Norway, sampled at the peak of the growing season. In sum, low molecular weight phenolic concentrations decreased with age. Apart from one apigenin glycoside, the low molecular weight phenolics co-varied similarly at all ages, suggesting a lack of temporal compound-specific prioritisation of this group. In contrast, the concentration of MeOH-soluble condensed tannins increased with age. The compositional shift fits well with several hypotheses that may provide proximate explanations for age patterns in PSM allocations, including both resource constraints and external pressures. Regardless of these explanations, our study adds an important perennial perspective (plant age) to temporal PSM patterns already well-known in boreal plant phenology (foliage age).
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Rodríguez-Rodríguez, César; Torres, Nimbe; Gutiérrez-Uribe, Janet A; Noriega, Lilia G; Torre-Villalvazo, Iván; Leal-Díaz, Ana M; Antunes-Ricardo, Marilena; Márquez-Mota, Claudia; Ordaz, Guillermo; Chavez-Santoscoy, Rocío A; Serna-Saldivar, Sergio O; Tovar, Armando R
2015-03-01
A diet rich in polyphenols can ameliorate some metabolic alterations associated with obesity and type 2 diabetes. Opuntia ficus-indica (OFI) is a plant rich in isorhamnetin glycosides and is highly consumed in Mexico. The purpose of this research was to determine the metabolic effect of an OFI extract on a mouse model of diet-induced obesity and in isolated pancreatic islets. OFI extract was added to a high fat (HF) diet at a low (0.3%) or high (0.6%) dose and administered to C57BL/6 mice for 12 weeks. Mice fed the HF diet supplemented with the OFI extract gained less body weight and exhibited significantly lower circulating total cholesterol, LDL cholesterol and HDL cholesterol compared to those fed the HF diet alone. The HF-OFI diet fed mice presented lower glucose and insulin concentration than the HF diet fed mice. However, the HF-OFI diet fed mice tended to have higher insulin concentration than control mice. The OFI extract stimulated insulin secretion in vitro, associated with increased glucose transporter 2 (GLUT2) and peroxisome proliferator-activated receptor gamma (PPARγ) mRNA content. Furthermore, the OFI extract improved glucose tolerance, and additionally increased energy expenditure. These metabolic improvements were associated with reduced adipocyte size, increased hepatic IRS1 tyr-608 and S6 K thr-389 phosphorylation. OFI isorhamnetin glycosides also diminished the hepatic lipid content associated with reduced mRNA expression of the endoplasmic reticulum stress markers and lipogenic enzymes and increased mRNA expression of genes related to fatty acid oxidation. Overall, the OFI extract prevented the development of metabolic abnormalities associated with diet-induced obesity.
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Yu, Xuejian; Yang, Jinshui; Wang, Entao; Li, Baozhen; Yuan, Hongli
2015-01-01
The aim of this study was to learn the interactions among the endophytic bacteria, the plant growth, the foliar spray of fulvic acid, and the accumulation of steviol glycosides in the leaves of Stevia rebaudiana. Metagenomic DNA was extracted from the Stevia leaves at different growth stages with or without the fulvic acid treatment; and the diversity of endophytic bacteria in Stevia leaves was estimated by pyrosequencing of 16S rRNA genes. As results, Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes were found to be the dominant phyla despite the growth stages and fulvic acid application. Stevia growth stages strongly regulated composition of endophytic community. The genera Agrobacterium (12.3%) and Erwinia (7.2%) dominated in seedling stage were apparently declined in the vegetable and initial flowering stages, while Sphingomonas and Methylobacterium increased in mature leaves at harvest time, which showed that the mature leaves of Stevia preferred to accumulate some certain endophytic bacteria. Sphingomonas and Methylobacterium constituted an important part of the core endophytic community and were positively correlated with the stevioside content and UGT74G1 gene expression, respectively; while Erwinia, Agrobacterium, and Bacillus were negatively correlated with the stevioside accumulation. Fulvic acid treatment accelerated the variation of endophytes along the growth stages and increased the steviol glycosides content. This is the first study to reveal the community composition of endophytic bacteria in the Stevia leaves, to evidence the strong effects of growth stage and fulvic acid application on the endophytes of Stevia, and to demonstrate the correlation between the endophytic bacteria and the steviol glycosides accumulation. PMID:26379644
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Iglesias-Fernández, Javier; Raich, Lluís; Ardèvol, Albert; Rovira, Carme
2015-02-01
Unraveling the conformational catalytic itinerary of glycoside hydrolases (GHs) is a growing topic of interest in glycobiology, with major impact in the design of GH inhibitors. β-xylanases are responsible for the hydrolysis of glycosidic bonds in β-xylans, a group of hemicelluloses of high biotechnological interest that are found in plant cell walls. The precise conformations followed by the substrate during catalysis in β-xylanases have not been unambiguously resolved, with three different pathways being proposed from structural analyses. In this work, we compute the conformational free energy landscape (FEL) of β-xylose to predict the most likely catalytic itineraries followed by β-xylanases. The calculations are performed by means of ab initio metadynamics, using the Cremer-Pople puckering coordinates as collective variables. The computed FEL supports only two of the previously proposed itineraries, 2 S O → [ 2,5 B] ǂ → 5 S 1 and 1 S 3 → [ 4 H 3 ] ǂ → 4 C 1 , which clearly appear in low energy regions of the FEL. Consistently, 2 S O and 1 S 3 are conformations preactivated for catalysis in terms of free energy/anomeric charge and bond distances. The results however exclude the O E → [ O S 2 ] ǂ → B 2,5 itinerary that has been recently proposed for a family 11 xylanase. Classical and ab initio QM/MM molecular dynamics simulations reveal that, in this case, the observed O E conformation has been enforced by enzyme mutation. These results add a word of caution on using modified enzymes to inform on catalytic conformational itineraries of glycoside hydrolases.
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Javed, Rabia; Usman, Muhammad; Yücesan, Buhara; Zia, Muhammad; Gürel, Ekrem
2017-01-01
This study aims to address the effects of different concentrations (0, 0.1, 1.0, 10, 100 or 1000 mg L -1 ) of engineered zinc oxide (ZnO) nanoparticles (34 nm in size) on growth parameters, steviol glycosides (rebaudioside A and stevioside) production and antioxidant activities in the tissue culture grown shoots of Stevia rebaudiana Bertoni. The highest percentage of shoot formation (89.6%) at 1 mg L -1 of ZnO nanoparticles concentration suggests a positive influence of ZnO nanoparticles on S. rebaudiana growth as compared to other treatments with or without ZnO nanoparticles. Additionally, HPLC results illustrate a significant enhancement of steviol glycosides (almost doubled as compared to the control) in micropropagated shoots grown under an oxidative stress of 1 mg L -1 of ZnO nanoparticles. This finding is further affirmed by an increased 2,2-diphenyl-1-picryl hydrazyl (DPPH) scavenging activity, total anti-oxidant capacity, total reducing power, total flavonoid content and total phenolic content, with an ascending oxidative pressure and generation of reactive oxygen species (ROS). However, the antioxidant activities, formation of secondary metabolites and the physiological parameters showed a sudden decline after crossing a threshold of 1 mg L -1 concentration of ZnO nanoparticles and falls to a minimum at 1000 mg L -1 , elucidating maximum phytotoxic effect of ZnO nanoparticles at this concentration. This is the first study evaluating both the favorable and adverse effects of ZnO nanoparticles employed to a highly valuable medicinal plant, S. rebaudiana. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
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Gallo, Monica; Vitulano, Manuela; Andolfi, Anna; DellaGreca, Marina; Conte, Esterina; Ciaravolo, Martina; Naviglio, Daniele
2017-06-01
Stevioside and rebaudioside A are the main diterpene glycosides present in the leaves of the Stevia rebaudiana plant, which is used in the production of foods and low-calorie beverages. The difficulties associated with their extraction and purification are currently a problem for the food processing industries. The objective of this study was to develop an effective and economically viable method to obtain a high-quality product while trying to overcome the disadvantages derived from the conventional transformation processes. For this reason, extractions were carried out using a conventional maceration (CM) and a cyclically pressurized extraction known as rapid solid-liquid dynamic extraction (RSLDE) by the Naviglio extractor (NE). After only 20 min of extraction using the NE, a quantity of rebaudioside A and stevioside equal to 1197.8 and 413.6 mg/L was obtained, respectively, while for the CM, the optimum time was 90 min. From the results, it can be stated that the extraction process by NE and its subsequent purification developed in this study is a simple, economical, environmentally friendly method for producing steviol glycosides. Therefore, this method constitutes a valid alternative to conventional extraction by reducing the extraction time and the consumption of toxic solvents and favouring the use of the extracted metabolites as food additives and/or nutraceuticals. As an added value and of local interest, the experiment was carried out on stevia leaves from the Benevento area (Italy), where a high content of rebaudioside A was observed, which exhibits a sweet taste compared to stevioside, which has a significant bitter aftertaste.
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Iglesias-Fernández, Javier; Raich, Lluís; Ardèvol, Albert
2015-01-01
Unraveling the conformational catalytic itinerary of glycoside hydrolases (GHs) is a growing topic of interest in glycobiology, with major impact in the design of GH inhibitors. β-xylanases are responsible for the hydrolysis of glycosidic bonds in β-xylans, a group of hemicelluloses of high biotechnological interest that are found in plant cell walls. The precise conformations followed by the substrate during catalysis in β-xylanases have not been unambiguously resolved, with three different pathways being proposed from structural analyses. In this work, we compute the conformational free energy landscape (FEL) of β-xylose to predict the most likely catalytic itineraries followed by β-xylanases. The calculations are performed by means of ab initio metadynamics, using the Cremer–Pople puckering coordinates as collective variables. The computed FEL supports only two of the previously proposed itineraries, 2SO → [2,5B]ǂ → 5S1 and 1S3 → [4H3]ǂ → 4C1, which clearly appear in low energy regions of the FEL. Consistently, 2SO and 1S3 are conformations preactivated for catalysis in terms of free energy/anomeric charge and bond distances. The results however exclude the OE → [OS2]ǂ → B2,5 itinerary that has been recently proposed for a family 11 xylanase. Classical and ab initio QM/MM molecular dynamics simulations reveal that, in this case, the observed OE conformation has been enforced by enzyme mutation. These results add a word of caution on using modified enzymes to inform on catalytic conformational itineraries of glycoside hydrolases. PMID:29560204
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Biology Today. Thinking Chemically about Biology.
ERIC Educational Resources Information Center
Flannery, Maura C.
1990-01-01
Discussed are applications of biochemistry. Included are designed drugs, clever drugs, carcinogenic structures, sugary wine, caged chemicals, biomaterials, marine chemistry, biopolymers, prospecting bacteria, and plant chemistry. (CW)
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Carpenter, Margaret A; Shaw, Martin; Cooper, Rebecca D; Frew, Tonya J; Butler, Ruth C; Murray, Sarah R; Moya, Leire; Coyne, Clarice J; Timmerman-Vaughan, Gail M
2017-08-01
Although starch consists of large macromolecules composed of glucose units linked by α-1,4-glycosidic linkages with α-1,6-glycosidic branchpoints, variation in starch structural and functional properties is found both within and between species. Interest in starch genetics is based on the importance of starch in food and industrial processes, with the potential of genetics to provide novel starches. The starch metabolic pathway is complex but has been characterized in diverse plant species, including pea. To understand how allelic variation in the pea starch metabolic pathway affects starch structure and percent amylose, partial sequences of 25 candidate genes were characterized for polymorphisms using a panel of 92 diverse pea lines. Variation in the percent amylose composition of extracted seed starch and (amylopectin) chain length distribution, one measure of starch structure, were characterized for these lines. Association mapping was undertaken to identify polymorphisms associated with the variation in starch chain length distribution and percent amylose, using a mixed linear model that incorporated population structure and kinship. Associations were found for polymorphisms in seven candidate genes plus Mendel's r locus (which conditions the round versus wrinkled seed phenotype). The genes with associated polymorphisms are involved in the substrate supply, chain elongation and branching stages of the pea carbohydrate and starch metabolic pathways. The association of polymorphisms in carbohydrate and starch metabolic genes with variation in amylopectin chain length distribution and percent amylose may help to guide manipulation of pea seed starch structural and functional properties through plant breeding.
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Lu, Hsiao-Pei; Liu, Po-Yu; Wang, Yu-bin; Hsieh, Ji-Fan; Ho, Han-Chen; Huang, Shiao-Wei; Lin, Chung-Yen; Hsieh, Chih-hao; Yu, Hon-Tsen
2018-01-01
Mammalian herbivores rely on microbial activities in an expanded gut chamber to convert plant biomass into absorbable nutrients. Distinct from ruminants, small herbivores typically have a simple stomach but an enlarged cecum to harbor symbiotic microbes; however, knowledge of this specialized gut structure and characteristics of its microbial contents is limited. Here, we used leaf-eating flying squirrels as a model to explore functional characteristics of the cecal microbiota adapted to a high-fiber, toxin-rich diet. Specifically, environmental conditions across gut regions were evaluated by measuring mass, pH, feed particle size, and metabolomes. Then, parallel metagenomes and metatranscriptomes were used to detect microbial functions corresponding to the cecal environment. Based on metabolomic profiles, >600 phytochemical compounds were detected, although many were present only in the foregut and probably degraded or transformed by gut microbes in the hindgut. Based on metagenomic (DNA) and metatranscriptomic (RNA) profiles, taxonomic compositions of the cecal microbiota were dominated by bacteria of the Firmicutes taxa; they contained major gene functions related to degradation and fermentation of leaf-derived compounds. Based on functional compositions, genes related to multidrug exporters were rich in microbial genomes, whereas genes involved in nutrient importers were rich in microbial transcriptomes. In addition, genes encoding chemotaxis-associated components and glycoside hydrolases specific for plant beta-glycosidic linkages were abundant in both DNA and RNA. This exploratory study provides findings which may help to form molecular-based hypotheses regarding functional contributions of symbiotic gut microbiota in small herbivores with folivorous dietary habits. PMID:29354108
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Pauchet, Yannick; Kirsch, Roy; Giraud, Sandra; Vogel, Heiko; Heckel, David G
2014-06-01
Xylophagous insects have evolved to thrive in a highly challenging environment. For example, wood-boring beetles from the family Cerambycidae feed exclusively on woody tissues, and to efficiently access the nutrients present in this sub-optimal environment, they have to cope with the lignocellulose barrier. Whereas microbes of the insect's gut flora were hypothesized to be responsible for the degradation of lignin, the beetle itself depends heavily on the secretion of a range of enzymes, known as plant cell wall degrading enzymes (PCWDEs), to efficiently digest both hemicellulose and cellulose networks. Here we sequenced the larval gut transcriptome of the Mulberry longhorn beetle, Apriona japonica (Cerambycidae, Lamiinae), in order to investigate the arsenal of putative PCWDEs secreted by this species. We combined our transcriptome with all available sequencing data derived from other cerambycid beetles in order to analyze and get insight into the evolutionary history of the corresponding gene families. Finally, we heterologously expressed and functionally characterized the A. japonica PCWDEs we identified from the transcriptome. Together with a range of endo-β-1,4-glucanases, we describe here for the first time the presence in a species of Cerambycidae of (i) a xylanase member of the subfamily 2 of glycoside hydrolase family 5 (GH5 subfamily 2), as well as (ii) an exopolygalacturonase from family GH28. Our analyses greatly contribute to a better understanding of the digestion physiology of this important group of insects, many of which are major pests of forestry worldwide. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Manduca sexta recognition and resistance among allopolyploid Nicotiana host plants
Lou, Yonggen; Baldwin, Ian T.
2003-01-01
Allopolyploid speciation occurs instantly when the genomes of different species combine to produce self-fertile offspring and has played a central role in the evolution of higher plants, but its consequences for adaptive responses are unknown. We compare herbivore-recognition and -resistance responses of the diploid species and putative ancestral parent Nicotiana attenuata with those of the two derived allopolyploid species Nicotiana clevelandii and Nicotiana bigelovii. Manduca sexta larvae attack all three species, and in N. attenuata attack is recognized when larval oral secretions are introduced to wounds during feeding, resulting in a jasmonate burst, a systemic amplification of trypsin inhibitor accumulation, and a release of volatile organic compounds, which function as a coordinated defense response that slows caterpillar growth and increases the probability of their being attacked. Most aspects of this recognition response are retained with modifications in one allotetraploid (N. bigelovii) but lost in the other (N. clevelandii). Differences between diploid and tetraploid species were apparent in delays (maximum 1 and 0.5 h, respectively) in the jasmonate burst, the elicitation of trypsin inhibitors and release of volatile organic compounds, and the constitutive levels of nicotine, trypsin inhibitors, diterpene glycosides, rutin, and caffeoylputrescine in the leaves. Resistance to M. sexta larvae attack was most strongly associated with diterpene glycosides, which were higher in the diploid than in the two allotetraploid species. Because M. sexta elicitors differentially regulate a large proportion of the N. attenuata transcriptome, we propose that these species are suited for the study of the evolution of adaptive responses requiring trans-activation mechanisms. PMID:14530394
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Jones, Darryl R; Uddin, Muhammed Salah; Gruninger, Robert J; Pham, Thi Thanh My; Thomas, Dallas; Boraston, Alisdair B; Briggs, Jonathan; Pluvinage, Benjamin; McAllister, Tim A; Forster, Robert J; Tsang, Adrian; Selinger, L Brent; Abbott, D Wade
2017-07-28
Enzyme activities that improve digestion of recalcitrant plant cell wall polysaccharides may offer solutions for sustainable industries. To this end, anaerobic fungi in the rumen have been identified as a promising source of novel carbohydrate active enzymes (CAZymes) that modify plant cell wall polysaccharides and other complex glycans. Many CAZymes share insufficient sequence identity to characterized proteins from other microbial ecosystems to infer their function; thus presenting challenges to their identification. In this study, four rumen fungal genes ( nf2152 , nf2215 , nf2523 , and pr2455 ) were identified that encode family 39 glycoside hydrolases (GH39s), and have conserved structural features with GH51s. Two recombinant proteins, NF2152 and NF2523, were characterized using a variety of biochemical and structural techniques, and were determined to have distinct catalytic activities. NF2152 releases a single product, β1,2-arabinobiose (Ara 2 ) from sugar beet arabinan (SBA), and β1,2-Ara 2 and α-1,2-galactoarabinose (Gal-Ara) from rye arabinoxylan (RAX). NF2523 exclusively releases α-1,2-Gal-Ara from RAX, which represents the first description of a galacto-(α-1,2)-arabinosidase. Both β-1,2-Ara 2 and α-1,2-Gal-Ara are disaccharides not previously described within SBA and RAX. In this regard, the enzymes studied here may represent valuable new biocatalytic tools for investigating the structures of rare arabinosyl-containing glycans, and potentially for facilitating their modification in industrial applications. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
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Mechanistic Investigations into the Application of Sulfoxides in Carbohydrate Synthesis
Brabham, Robin
2016-01-01
Abstract The utility of sulfoxides in a diverse range of transformations in the field of carbohydrate chemistry has seen rapid growth since the first introduction of a sulfoxide as a glycosyl donor in 1989. Sulfoxides have since developed into more than just anomeric leaving groups, and today have multiple roles in glycosylation reactions. These include as activators for thioglycosides, hemiacetals, and glycals, and as precursors to glycosyl triflates, which are essential for stereoselective β‐mannoside synthesis, and bicyclic sulfonium ions that facilitate the stereoselective synthesis of α‐glycosides. In this review we highlight the mechanistic investigations undertaken in this area, often outlining strategies employed to differentiate between multiple proposed reaction pathways, and how the conclusions of these investigations have and continue to inform upon the development of more efficient transformations in sulfoxide‐based carbohydrate synthesis. PMID:26744250
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A reagent-controlled SN2-glycosylation for the direct synthesis of β-linked 2-deoxy-sugars.
Issa, John Paul; Bennett, Clay S
2014-04-16
The efficient and stereoselective construction of glycosidic linkages remains one of the most formidable challenges in organic chemistry. This is especially true in cases such as β-linked deoxy-sugars, where the outcome of the reaction cannot be controlled using the stereochemical information intrinsic to the glycosyl donor. Here we show that p-toluenesulfonic anhydride activates 2-deoxy-sugar hemiacetals in situ as electrophilic species, which react stereoselectively with nucleophilic acceptors to produce β-anomers exclusively. NMR studies confirm that, under these conditions, the hemiacetal is quantitatively converted into an α-glycosyl tosylate, which is presumably the reactive species in the reaction. This approach demonstrates that use of promoters that activate hemiacetals as well-defined intermediates can be used to permit stereoselective glycosylation through an SN2-pathway.
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Presidential Green Chemistry Challenge: 2001 Small Business Award
Presidential Green Chemistry Challenge 2001 award winner, EDEN Bioscience, discovered and commercialized harpins: nontoxic, naturally occurring, biodegradable proteins that activate a plant's defense and growth mechanisms.
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ERIC Educational Resources Information Center
Ravia, Silvana; Gamenara, Daniela; Schapiro, Valeria; Bellomo, Ana; Adum, Jorge; Seoane, Gustavo; Gonzalez, David
2006-01-01
The use of biocatalysis and biotransformations are important tools in green chemistry. The enantioselective reduction of a ketone by crude plant parts, using carrot ("Daucus carota") as the reducing agent is presented. The experiment introduces an example of a green chemistry procedure that can be tailored to fit in a regular laboratory session.…
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Crystal structure of a putative exo-β-1,3-galactanase from Bifidobacterium bifidum S17
DOE Office of Scientific and Technical Information (OSTI.GOV)
Godoy, Andre S.; de Lima, Mariana Z. T.; Camilo, Cesar M.
2016-03-16
Given the current interest in second-generation biofuels, carbohydrate-active enzymes have become the most important tool to overcome the structural recalcitrance of the plant cell wall. While some glycoside hydrolase families have been exhaustively described, others remain poorly characterized, especially with regard to structural information. The family 43 glycoside hydrolases are a diverse group of inverting enzymes; the available structure information on these enzymes is mainly from xylosidases and arabinofuranosidase. Currently, only one structure of an exo-β-1,3-galactanase is available. Here, the production, crystallization and structure determination of a putative exo-β-1,3-galactanase fromBifidobacterium bifidumS17 (BbGal43A) are described.BbGal43A was successfully produced and showed activitymore » towards synthetic galactosides.BbGal43A was subsequently crystallized and data were collected to 1.4 Å resolution. The structure shows a single-domain molecule, differing from known homologues, and crystal contact analysis predicts the formation of a dimer in solution. Further biochemical studies are necessary to elucidate the differences betweenBbGal43A and its characterized homologues.« less
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Benayad, Zakia; Gómez-Cordovés, Carmen; Es-Safi, Nour Eddine
2014-01-01
Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon. PMID:25393509
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Benayad, Zakia; Gómez-Cordovés, Carmen; Es-Safi, Nour Eddine
2014-11-11
Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon.
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Antioxidant lipoxygenase inhibitors from the leaf extracts of Simmondsia chinensis.
Abdel-Mageed, Wael Mostafa; Bayoumi, Soad Abdel Latief Hassan; Salama, Awwad Abdoh Radwan; Salem-Bekhit, Mounir Mohamed; Abd-Alrahman, Sherif Hussein; Sayed, Hanaa Mohamed
2014-09-01
To isolate and identify chemical constituents with antioxidant and lipoxygenase inhibitory effects of the ethanolic extract of Simmondsia chinensis (Jojoba) leaves. The alcoholic extract was subjected to successive solvent fractionation. The antioxidant active fractions (chloroform, ethyl acetate and aqueous fractions) were subjected to a combination of different chromatographic techniques guided by the antioxidant assay with DPPH. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. The antioxidant activity was assessed quantitively using DPPH and β-carotene methods. The inhibitory potential against enzyme lipoxygenase was assessed on soybean lipoxygenase enzyme. Ten flavonoids and four lignans were isolated. Flavonoid aglycones showed stronger antioxidant and lipoxygenase inhibitory effects than their glycosides. Lignoid glycosides showed moderate to weak antioxidant and lipoxygenase inhibitory effects. A total of 14 compounds were isolated and identified from Simmondsia chinensis; 12 of them were isolated for the first time. This is the first report that highlights deeply on the phenolic content of jojoba and their potential biological activities and shows the importance of this plant as a good source of phenolics in particular the flavonoid content. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.
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Dietary pectic glycans are degraded by coordinated enzyme pathways in human colonic Bacteroides.
Luis, Ana S; Briggs, Jonathon; Zhang, Xiaoyang; Farnell, Benjamin; Ndeh, Didier; Labourel, Aurore; Baslé, Arnaud; Cartmell, Alan; Terrapon, Nicolas; Stott, Katherine; Lowe, Elisabeth C; McLean, Richard; Shearer, Kaitlyn; Schückel, Julia; Venditto, Immacolata; Ralet, Marie-Christine; Henrissat, Bernard; Martens, Eric C; Mosimann, Steven C; Abbott, D Wade; Gilbert, Harry J
2018-02-01
The major nutrients available to human colonic Bacteroides species are glycans, exemplified by pectins, a network of covalently linked plant cell wall polysaccharides containing galacturonic acid (GalA). Metabolism of complex carbohydrates by the Bacteroides genus is orchestrated by polysaccharide utilization loci (PULs). In Bacteroides thetaiotaomicron, a human colonic bacterium, the PULs activated by different pectin domains have been identified; however, the mechanism by which these loci contribute to the degradation of these GalA-containing polysaccharides is poorly understood. Here we show that each PUL orchestrates the metabolism of specific pectin molecules, recruiting enzymes from two previously unknown glycoside hydrolase families. The apparatus that depolymerizes the backbone of rhamnogalacturonan-I is particularly complex. This system contains several glycoside hydrolases that trim the remnants of other pectin domains attached to rhamnogalacturonan-I, and nine enzymes that contribute to the degradation of the backbone that makes up a rhamnose-GalA repeating unit. The catalytic properties of the pectin-degrading enzymes are optimized to protect the glycan cues that activate the specific PULs ensuring a continuous supply of inducing molecules throughout growth. The contribution of Bacteroides spp. to metabolism of the pectic network is illustrated by cross-feeding between organisms.
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Stevia preferences in Wistar rats.
Núñez Martínez, Paula; Argüelles Luis, Juan; Perillán Méndez, Carmen
2016-11-01
The Stevia rebaudiana plant is likely to become a major source of high-potency sweetener for the growing natural-food market. S. rebaudiana is the source of a number of sweet diterpenoid glycosides, but the major sweet constituents are rebaudioside A and stevioside. These two constituents have similar pharmacokinetic and metabolic profiles in rats and humans, and thus, studies carried out with either steviol glycoside are relevant to both. Other studies illustrate the diversity of voluntary sweet intake in mammals. This study was done using a series of two-bottle tests that compared a wide range of sweetener concentrations versus saccharin concentrations and versus water. Wistar rats displayed preferences for stevia extract and pure rebaudioside A solutions over water at a range of concentrations (0.001% to 0.3%), and their intake peak occurred at 0.1% concentration. They also preferred solutions prepared with a commercial rebaudioside A plus erythritol mixture to water, and their peak was at 2% concentration. The present study provides new information about the responses of Wistar rats to stevia compounds and commercial stevia products such as Truvia. These results could help with the appropriate dosage selection for focused behavioral and physiological studies on stevia.
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Dewitte, Griet; Walmagh, Maarten; Diricks, Margo; Lepak, Alexander; Gutmann, Alexander; Nidetzky, Bernd; Desmet, Tom
2016-09-10
UDP-glycosyltransferases (UGTs) are a promising class of biocatalysts that offer a sustainable alternative for chemical glycosylation of natural products. In this study, we aimed to characterize plant-derived UGTs from the GT-1 family with an emphasis on their acceptor promiscuity and their potential application in glycosylation processes. Recombinant expression in E. coli provided sufficient amounts of enzyme for the in-depth characterization of the salicylic acid UGT from Capsella rubella (UGT-SACr) and the stevia UGT from Stevia rebaudiana (UGT-76G1Sr). The latter was found to have a remarkably broad specificity with activities on a wide diversity of structures, from aliphatic and branched alcohols, over small phenolics to larger flavonoids, terpenoids and even higher glycoside compounds. As an example for its industrial potential, the glycosylation of curcumin was thoroughly evaluated. Under optimized conditions, 96% of curcumin was converted within 24h into the corresponding curcumin β-glycosides. In addition, the reaction was performed in a coupled system with sucrose synthase from Glycine max, to enable the cost-efficient (re)generation of UDP-Glc from sucrose as abundant and renewable resource. Copyright © 2016 Elsevier B.V. All rights reserved.
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Santos-Zea, Liliana; Fajardo-Ramírez, Oscar R; Romo-López, Irasema; Gutiérrez-Uribe, Janet A
2016-03-01
Separation of potentially bioactive components from foods and plant extracts is one of the main challenges for their study. Centrifugal partition chromatography has been a successful technique for the screening and identification of molecules with bioactive potential, such as steroidal saponins. Agave is a source of steroidal saponins with anticancer potential, though the activity of these compounds in concentrated agave sap has not been yet explored. In this study, fast centrifugal partition chromatography (FCPC) was used coupled with in vitro tests on HT-29 cells as a screening procedure to identify apoptotic saponins from an acetonic extract of concentrated agave sap. The three most bioactive fractions obtained by FCPC at partition coefficients between 0.23 and 0.4 contained steroidal saponins, predominantly magueyoside b. Flow cytometry analysis determined that the fraction rich in kammogenin and manogenin glycosides induced apoptosis, but when gentrogenin and hecogenin glycosides were also found in the fraction, a necrotic effect was observed. In conclusion, this study provides the evidence that steroidal saponins in concentrated agave sap were potential inductors of apoptosis and that it was possible to separate them using fast centrifugal partition chromatography.
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Characterization of amygdalin-degrading Lactobacillus species.
Menon, R; Munjal, N; Sturino, J M
2015-02-01
Cyanogenic glycosides are phytotoxic secondary metabolites produced by some crop plants. The aim of this study was to identify lactic acid bacteria (LAB) capable of catabolizing amygdalin, a model cyanogenic glycoside, for use in the biodetoxification of amygdalin-containing foods and feeds. Amygdalin-catabolizing lactobacilli were characterized using a combination of cultivation-dependent and molecular assays. Lactobacillus paraplantarum and Lactobacillus plantarum grew robustly on amygdalin (Amg(+)), while other LAB species typically failed to catabolize amygdalin (Amg(-)). Interestingly, high concentrations of amygdalin and two of its metabolic derivatives (mandelonitrile and benzaldehyde) inhibited the growth of Lact. plantarum RENO 0093. The differential regulation of genes tentatively involved in cyanohydrin metabolism illustrated that the metabolism of amygdalin- and glucose-grown cultures also differed significantly. Amygdalin fermentation was a relatively uncommon phenotype among the LAB and generally limited to strains from the Lact. plantarum group. Phenotype microarrays (PM) enabled strain-level discrimination between closely related strains within a species and suggested that phenotypic differences might affect niche specialization. Amygdalin-degrading lactobacilli with practical application in the biodetoxification of amygdalin were characterized. These strains show potential for use as starter cultures to improve the safety of foods and feeds. © 2014 The Society for Applied Microbiology.
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Secretome profiling reveals temperature-dependent growth of Aspergillus fumigatus.
Wang, Dongyu; Zhang, Lili; Zou, Haiyue; Wang, Lushan
2018-05-01
Aspergillus fumigatus is a ubiquitous opportunistic fungus. In this study, systematic analyses were carried out to study the temperature adaptability of A. fumigatus. A total of 241 glycoside hydrolases and 69 proteases in the secretome revealed the strong capability of A. fumigatus to degrade plant biomass and protein substrates. In total, 129 pathogenesis-related proteins detected in the secretome were strongly correlated with glycoside hydrolases and proteases. The variety and abundance of proteins remained at temperatures of 34°C-45°C. The percentage of endo-1,4-xylanase increased when the temperature was lowered to 20°C, while the percentage of cellobiohydrolase increased as temperature was increased, suggesting that the strain obtains carbon mainly by degrading xylan and cellulose, and the main types of proteases in the secretome were aminopeptidases and carboxypeptidases. Only half of the proteins were retained and their abundance declined to 9.7% at 55°C. The activities of the remaining β-glycosidases and proteases were merely 35% and 24%, respectively, when the secretome was treated at 60°C for 2 h. Therefore, temperatures >60°C restrict the growth of A. fumigatus.
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A Novel Diterpene Glycoside with Nine Glucose Units from Stevia rebaudiana Bertoni
Prakash, Indra; Ma, Gil; Bunders, Cynthia; Charan, Romila D.; Ramirez, Catherine; Devkota, Krishna P.; Snyder, Tara M.
2017-01-01
Following our interest in new diterpene glycosides with better taste profiles than that of Rebaudioside M, we have recently isolated and characterized Rebaudioside IX—a novel steviol glycoside—from a commercially-supplied extract of Stevia rebaudiana Bertoni. This molecule contains a hexasaccharide group attached at C-13 of the central diterpene core, and contains three additional glucose units when compared with Rebaudioside M. Here we report the complete structure elucidation—based on extensive Nuclear Magnetic Resonance (NMR) analysis (1H, 13C, Correlation Spectroscopy (COSY), Heteronuclear Single Quantum Coherence-Distortionless Enhancement Polarization Transfer (HSQC-DEPT), Heteronuclear Multiple Bond Correlation (HMBC), 1D Total Correlation Spectroscopy (TOCSY), Nuclear Overhauser Effect Spectroscopy (NOESY)) and mass spectral data—of this novel diterpene glycoside with nine sugar moieties and containing a relatively rare 1→6 α-linked glycoside. A steviol glycoside bearing nine glucose units is unprecedented in the literature, and could have an impact on the natural sweetener catalog. PMID:28146121
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Yu, Xiaofeng; Zhu, Yiling; Fan, Jingyi; Wang, Dujun; Gong, Xiaohui; Ouyang, Zhen
2017-08-01
In order to determine the molecular mechanism underlying the influence of frost on chemical changes in mulberry leaves, the UFGT activity, expression level, and accumulation of flavonoid glycosides in mulberry leaves (Morus alba L.) were studied. The expression of UFGT gene was investigated by quantitative real-time PCR (qRT-PCR) and the UFGT activity, accumulation of flavonoid glycosides was studied by high performance liquid chromatography. Then, the correlation between the expression level of UFGT, the UFGT activity, and the flavonoid glycosides accumulation with temperature was explored. The accumulation of isoquercitrin and astragalin is significantly positively correlated with UFGT gene expression and UFGT activity. On the contrary, the average temperature was significantly negatively correlated with the level of UFGT gene expression and UFGT activity. The results show that after frost, low temperature can induce the expression of UFGT gene in mulberry leaves, resulting in the accumulation of flavonoid glycosides. © 2017 Wiley-VHCA AG, Zurich, Switzerland.
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Yuan, Yue; Zhou, Rong; Li, Dongliang; Luo, Cheng; Li, Guoyou
2018-03-01
A simple and efficient method combining ultrasound-assisted extraction, the conditions of which were optimized by response surface methodology, with liquid chromatography and tandem mass spectrometry was established and validated for the absolute quantification of nine non-volatile neutral glycosides originating from tobacco (Nicotiana tobaccum L.) leaves, comprising three phenolic glycosides, one benzanoid glycoside, and five sesquiterpene glycosides within three isomers, originating from tobacco leaves. Factors of extraction time, sample quantity, extraction solvent, liquid chromatographic conditions, and electrospray ionization parameters were carefully investigated to ensure the selectivity and sensitivity of the method. All calibration curves showed excellent coefficients of determination ranging from 0.9940 to 0.9996, within the range of tested concentrations. The limits of detection and quantification were 2.33-25.9 and 7.06-78.5 ng/mL, respectively. Satisfactory values of accuracy were between 80.1 to 107.9% among different sample matrixes. The relative standard deviations of intra- and inter-day analysis were less than 13.7 and 13.0% respectively. The developed method was successfully applied in a pilot study to determine the amounts of the nine endogenous glycosides in real flue-cured tobacco samples obtained from different habitats in China. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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HPLC-DAD-ESI/MS(n) profiling of phenolic compounds from Lathyrus cicera L. seeds.
Ferreres, F; Magalhães, S C Q; Gil-Izquierdo, A; Valentão, P; Cabrita, A R J; Fonseca, A J M; Andrade, P B
2017-01-01
Lathyrus cicera L. seeds are of interest for food and feed purposes. Despite the recognized antioxidant activity of the seeds, arising from the phenolic fraction, their phenolic compounds have not been studied in depth yet. Therefore, to determine the phenolics profile of these seeds, a target analysis was performed using high-performance liquid chromatography coupled to photodiode-array detection and electrospray ionization/ion trap mass spectrometry (HPLC-DAD-ESI/MS(n)). Thirty-seven glycosylated flavonoids were identified for the first time in the seeds of this species and, according to their MS fragmentation, clustered in flavonol-3-O-di-/tri-glycosides-7-O-rhamnosides and other flavonol-glycosides, and flavonol-3-O-(cinnamoyl)glycoside-7-O-rhamnosides, flavonol-3-O-(dihydrophaseoyl, cinnamoyl)glycoside-7-O-rhamnosides and flavonol-3-O-(malonyl)glycoside-7-O-rhamnosides. Glycosides of kaempferol were the main flavonoids found (10 non-acylated and 21 acylated), followed by those of quercetin (3) and those of isorhamnetin, apigenin and luteolin (1). The most abundant flavonols were identified as kaempferol-3-O-(2-hexosyl)hexoside-7-O-rhamnosides. The methodology used allowed to increase the knowledge on a relevant phytochemical class of seeds from L. cicera. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Lehtonen, Henna-Maria; Lehtinen, Outi; Suomela, Jukka-Pekka; Viitanen, Matti; Kallio, Heikki
2010-01-13
Glucuronidation and excretion of sea buckthorn and lingonberry flavonols were investigated in a postprandial trial by analyzing the intact forms of flavonol glycosides as well as glucuronides in plasma, urine, and feces. Four study subjects consumed sea buckthorn (study day 1) and lingonberry (study day 2) breakfasts, and blood, urine, and fecal samples were collected for 8, 24, and 48 h, respectively. Both glycosides and glucuronides of the flavonol quercetin as well as kaempferol glucuronides were detected in urine and plasma samples after the consumption of lingonberries; 14% of flavonols in urine were glycosides, and 86% were glucuronidated forms (wt %). After the consumption of sea buckthorn, 5% of flavonols excreted in urine were detected intact, and 95% as the glucuronides (wt %). Solely glucuronides of flavonols isorhamnetin and quercetin were found in plasma after the consumption of sea buckthorn berries. Only glycosides were detected in the feces after each berry trial. Flavonol glycosides and glucuronides remained in blood and urine quite long, and the peak concentrations appeared slightly later than previously described. The berries seemed to serve as a good flavonol supply, providing steady flavonol input for the body for a relatively long time.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Potapovich, Alla I.; Biology Department, Belarus State University, Skorina Prosp. 10, Minsk 220050; Lulli, Daniela
Molecular mechanisms underlying modulation of inflammatory responses in primary human keratinocytes by plant polyphenols (PPs), namely the glycosylated phenylpropanoid verbascoside, the stilbenoid resveratrol and its glycoside polydatin, and the flavonoid quercetin and its glycoside rutin were evaluated. As non-lethal stimuli, the prototypic ligand for epidermal growth factor receptor (EGFR) transforming growth factor alpha (TGFalpha), the combination of tumor necrosis factor (TNFalpha) and interferon (IFNgamma) (T/I), UVA + UVB irradiation, and bacterial lipopolysaccharide (LPS) were used. We demonstrated differential modulation of inflammatory responses in keratinocytes at signal transduction, gene transcription, and protein synthesis levels as a function of PP chemical structure,more » the pro-inflammatory trigger used, and PP interaction with intracellular detoxifying systems. The PPs remarkably inhibited constitutive, LPS- and T/I-induced but not TGFalpha-induced ERK phosphorylation. They also suppressed NFkappaB activation by LPS and T/I. Verbascoside and quercetin invariably impaired EGFR phosphorylation and UV-associated aryl hydrocarbon receptor (AhR)-mediated signaling, while rutin, polydatin and resveratrol did not affect EGFR phosphorylation and further activated AhR machinery in UV-exposed keratinocytes. In general, PPs down-regulated gene expression of pro-inflammatory cytokines/enzymes, except significant up-regulation of IL-8 observed under stimulation with TGFalpha. Both spontaneous and T/I-induced release of IL-8 and IP-10 was suppressed, although 50 {mu}M resveratrol and polydatin up-regulated IL-8. At this concentration, resveratrol activated both gene expression and de novo synthesis of IL-8 and AhR-mediated mechanisms were involved. We conclude that PPs differentially modulate the inflammatory response of human keratinocytes through distinct signal transduction pathways, including AhR and EGFR. - Graphical abstract: Display Omitted Highlights: > Effects of plant polyphenols on inflammatory responses in human keratinocytes. > Inflammatory stimuli used: TGFalpha, TNFalpha+IFNgamma, UVA+UVB, and LPS. > Inflammatory pathways connected with NFB, ERK1/2, EGFR, and AhR were investigated. > Plant polyphenols, flavonoids, stilbenoids, and phenylpropanoids, were studied. > Modulation of inflammation depends on phenolic core structure and glycosylation.« less
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Phenolic Glycosides in Populus tremuloides and their Effects on Long-Term Ungulate Browsing.
Lastra, R A; Kenkel, N C; Daayf, F
2017-10-01
In the aspen-grassland ecotone of Riding Mountain, Manitoba, lightly browsed vigorous clones of trembling aspen (Populus tremuloides Michx.) occur in close proximity to heavily browsed dieback clones. This study examines whether intraspecific variation in the production of phenolic glycosides is correlated with this strong dichotomy in clonal vigor. Individual clones were sampled over four years at three sites located along a gradient of increasing soil moisture stress. At each site, eight aspen clones of similar size and age were sampled: four vigorous and four dieback clones (total of 24 individual clones). The severity of wapiti (elk) browsing was assessed as the ratio of browse-damaged to total branches per aspen ramet. Statistically significant differences in foliar concentrations of the phenolic glycosides salicortin and tremulacin were observed between vigorous and dieback clones: a mean of 14.8% dry mass for lightly browsed (vigorous) clones, versus just 7.0% for heavily browsed (dieback) clones. Mean concentrations of foliar phenolics were also significantly greater in more moisture-stressed sites. These results demonstrate that the strong dichotomy in clonal vigor (vigorous versus dieback clones) is associated with large differences in phenolic glycoside production. Vigorous clone ramets produce high amounts of phenolic glycosides and have low levels of herbivore browsing and low mortality rates, whereas dieback clone ramets have low amounts of phenolic glycosides and much higher herbivore browsing and mortality rates. This suggests that intraspecific variation in phenolic glycosides in trembling aspen is an important predisposing factor leading to ramet mortality, and by extension to the decline of aspen clones.
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Li, Qince; Pogwizd, Steven M; Prabhu, Sumanth D; Zhou, Lufang
2014-01-01
Cardiac glycosides have been used for the treatment of heart failure because of their capabilities of inhibiting Na+/K+ ATPase (NKA), which raises [Na+]i and attenuates Ca2+ extrusion via the Na+/Ca2+ exchanger (NCX), causing [Ca2+]i elevation. The resulting [Ca2+]i accumulation further enhances Ca2+-induced Ca2+ release, generating the positive inotropic effect. However, cardiac glycosides have some toxic and side effects such as arrhythmogenesis, confining their extensive clinical applications. The mechanisms underlying the proarrhythmic effect of glycosides are not fully understood. Here we investigated the mechanisms by which glycosides could cause cardiac arrhythmias via impairing mitochondrial energetics using an integrative computational cardiomyocyte model. In the simulations, the effect of glycosides was mimicked by blocking NKA activity. Results showed that inhibiting NKA not only impaired mitochondrial Ca2+ retention (thus suppressed reactive oxygen species (ROS) scavenging) but also enhanced oxidative phosphorylation (thus increased ROS production) during the transition of increasing workload, causing oxidative stress. Moreover, concurrent blocking of mitochondrial Na+/Ca2+ exchanger, but not enhancing of Ca2+ uniporter, alleviated the adverse effects of NKA inhibition. Intriguingly, NKA inhibition elicited Ca2+ transient and action potential alternans under more stressed conditions such as severe ATP depletion, augmenting its proarrhythmic effect. This computational study provides new insights into the mechanisms underlying cardiac glycoside-induced arrhythmogenesis. The findings suggest that targeting both ion handling and mitochondria could be a very promising strategy to develop new glycoside-based therapies in the treatment of heart failure.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Mattsson, Joel L., E-mail: jmattsson@indy.rr.com
2007-09-01
A perusal of research presented at the Annual Society of Toxicology Meetings, or in nearly any toxicology journal, will show that the overwhelming emphasis of toxicology research is on synthetic chemistries. Because of substantial potency and exposure to natural chemicals, the overwhelming focus on synthetic chemistries cannot lead to a realistic understanding of chemical risk to the general population. Natural chemicals, simply because of their abundance and potency, may be as likely to be a public health concern and to be involved in chemical interactions (natural:natural, natural:pharmaceutical; or natural:synthetic) as are environmental levels of synthetic chemicals. All plants have amore » mix of natural self-defense chemistries and mycotoxins that, when tested in a manner comparable to synthetic pesticides, cause the entire spectrum of toxic effects. As a further complication, plants also escalate much of their self-defense chemistry when attacked by insects and fungi, and damaged crops often have higher mycotoxins levels. Effective crop protection will typically reduce the plant's levels of self-defense toxicants and mycotoxins, but may add residues of synthetic pesticides or add some other risk variable. In addition, cooking may also alter the food chemistry (e.g., acrylamide). The mixtures toxicologist needs to address the real world mixture of natural and synthetic chemicals. Public policy on crop-food safety cannot be sensibly guided without these data and large voids in our understanding of risks from real-world mixtures cannot be in the public interest.« less
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Mattsson, Joel L
2007-09-01
A perusal of research presented at the Annual Society of Toxicology Meetings, or in nearly any toxicology journal, will show that the overwhelming emphasis of toxicology research is on synthetic chemistries. Because of substantial potency and exposure to natural chemicals, the overwhelming focus on synthetic chemistries cannot lead to a realistic understanding of chemical risk to the general population. Natural chemicals, simply because of their abundance and potency, may be as likely to be a public health concern and to be involved in chemical interactions (natural:natural, natural:pharmaceutical; or natural:synthetic) as are environmental levels of synthetic chemicals. All plants have a mix of natural self-defense chemistries and mycotoxins that, when tested in a manner comparable to synthetic pesticides, cause the entire spectrum of toxic effects. As a further complication, plants also escalate much of their self-defense chemistry when attacked by insects and fungi, and damaged crops often have higher mycotoxins levels. Effective crop protection will typically reduce the plant's levels of self-defense toxicants and mycotoxins, but may add residues of synthetic pesticides or add some other risk variable. In addition, cooking may also alter the food chemistry (e.g., acrylamide). The mixtures toxicologist needs to address the real world mixture of natural and synthetic chemicals. Public policy on crop-food safety cannot be sensibly guided without these data and large voids in our understanding of risks from real-world mixtures cannot be in the public interest.
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NASA Astrophysics Data System (ADS)
Kohl, L.; Philben, M. J.; Edwards, K. A.; Podrebarac, F. A.; Jamie, W.; Ziegler, S. E.
2017-12-01
Warmer climates have been associated with reduced soil organic matter (SOM) bioreactivity, lower respiration rates at a given temperature, which is typically attributed to the presence of more decomposed SOM. Cross site studies, however, indicate that ecosystem regime shifts associated with long-term climate warming can affect SOM properties through changes in vegetation and plant litter inputs to soils. The relative importance of these two controls, diagenesis and inputs, on SOM properties as ecosystems experience climate warming remains poorly understood. To address this, we characterized the elemental, chemical (nuclear magnetic resonance spectroscopy and total hydrolysable amino acids), and isotopic composition of plant litter and SOM across a well-constrained mesic boreal forest latitudinal transect in Atlantic Canada. Results across forest sites within each of three climate regions indicated that (1) climate history and diagenesis affect distinct parameters of SOM chemistry, (2) increases in SOM bioreactivity with latitude were associated with elevated proportions of carbohydrates relative to plant waxes and lignin, and (3) despite the common forest type across regions, differences in SOM chemistry by climate region were associated with chemically distinct litter inputs and not different degrees of diagenesis. Climate effects on vascular plant litter chemistry explained only part of the regional differences in SOM chemistry, most notably the higher protein content of SOM from warmer regions. Greater proportions of lignin and aliphatic compounds and smaller proportions of carbohydrates in warmer sites' soils were explained by the higher proportion of vascular plant relative to moss litter in the warmer forests. These results indicate that a climate induced decrease in the proportion of moss inputs will not only impact SOM chemistry but also increase the resistance of SOM to decomposition, thus significantly altering SOM cycling in these boreal forest soils.