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Sample records for cyanogenic glucoside dhurrin

  1. Dhurrin-6'-glucoside, a cyanogenic diglucoside from Sorghum bicolor.

    PubMed

    Selmar, D; Irandoost, Z; Wray, V

    1996-10-01

    A novel cyanogenic diglucoside has been isolated from methanolic extracts of young seedlings of Sorghum bicolor. Its structure was established as dhurrin-6-glucoside from NMR, mass spectrometry and enzymatic hydrolysis data. Compared with dhurrin, which is the major cyanogenic glucoside in sorghum leaves, dhurrin-6-glucoside occurs only in low concentrations. In contrast, however, the diglucoside is present in significant amounts in guttation droplets of young Sorghum seedlings. The presence of the diglucoside and its occurrence in apoplasmic exudates supports the hypothesis that diglucosides represent metabolites of cyanogenic monoglucosides which can be translocated within the plant. PMID:8987580

  2. Biosynthesis of the Cyanogenic Glucoside Dhurrin in Seedlings of Sorghum bicolor (L.) Moench and Partial Purification of the Enzyme System Involved 1

    PubMed Central

    Halkier, Barbara Ann; Møller, Birger Lindberg

    1989-01-01

    The cyanogenic glucoside dhurrin is rapidly synthesized in etiolated seedlings of Sorghum bicolor (L.) Moench. The dhurrin content of the seedlings increases sigmoidally with the germination time. Shoots of 10 centimeters height contain 850 nanomoles of dhurrin per shoot corresponding to 6% of the dry weight. The biosynthetic activity sharply rises upon germination and reaches a maximum level of 10 nanomoles dhurrin/(hour × shoot) after 48 hours when the shoots are 3 centimeters high. This maximum level is followed by a sharp decline in activity when germination time exceeds 65 hours. Dhurrin and the dhurrin-synthesizing enzyme system are primarily located in the upper part of the etiolated shoot where both are evenly distributed between the coleoptile, the primary leaves and the upper 0.5 centimeter of the first internode including the shoot apex. Dhurrin constitutes 30% of the dry weight of the upper 1.2 centimeter of 10 centimeter high shoots. The seed and root contain neither dhurrin nor the dhurrin-synthesizing enzyme system. The codistribution of dhurrin and the enzyme system throughout the seedling indicates that production and storage sites are located within the same cell. Purification of the dhurrin-synthesizing enzyme by gel filtration or by sucrose gradient centrifugations results in a tenfold increase in specific activity. Further purification is accompained by a decline in specific activity due to loss of essential components as demonstrated by reconstitution experiments. Images Figure 7 Figure 8 PMID:16666964

  3. The rare cyanogen proteacin, and dhurrin, from foliage of Polyscias australiana, a tropical Araliaceae.

    PubMed

    Miller, Rebecca E; Tuck, Kellie L

    2013-09-01

    The tyrosine-derived cyanogenic di-glucoside proteacin and related mono-glucoside dhurrin were identified as the cyanogens in foliage of the tropical tree species Polyscias australiana, present in the approximate ratio 9:1. To date cyanogenic glycosides have not been characterised from the Araliaceae or the Apiales. Concentrations of cyanogenic glycosides varied significantly between plant parts and with leaf age, with the highest concentrations in young emerging leaves (mean 2217.1 μg CN g(-1) dry wt), petioles (rachis; 1487.1 μg CN g(-1) dry wt) and floral buds (265.8 μg CN g(-1) dry wt). Between 2% and 10% of nitrogen in emerging leaves and petioles was present as cyanogenic glycosides. With the exception of floral buds, all tissues apparently lack a specific cyanogenic β-glucosidase to catalyse the first step in the breakdown of these cyanogenic glycosides. Only with the addition of emulsin, an exogenous non-specific β-glucosidase from almonds, were high concentrations of cyanogenic glycosides detected, as much as 20-fold greater than the low to negligible cyanogenic glycoside concentrations determined in the absence of exogenous enzyme. High concentrations of cyanogens in young tissues may confer protection, but may also be a nitrogen source during leaf expansion. PMID:23566716

  4. The biosynthesis of cyanogenic glucosides in higher plants. Identification of three hydroxylation steps in the biosynthesis of dhurrin in Sorghum bicolor (L. ) Moench and the involvement of 1-ACI-nitro-2-(p-hydroxyphenyl)ethane as an intermediate

    SciTech Connect

    Halkier, B.A.; Moller, B.L. )

    1990-12-05

    N-Hydroxytyrosine, (E)- and (Z)-p-hydroxyphenyl-acetaldehyde oxime, p-hydroxyphenylacetonitrile, and p-hydroxymandelonitrile are established intermediates in the biosynthesis of the tyrosine-derived cyanogenic glucoside dhurrin. Simultaneous measurements of oxygen consumption and biosynthetic activity using a microsomal enzyme system isolated from etiolated sorghum seedlings demonstrate a requirement for three oxygen molecules in the conversion of tyrosine to p-hydroxymandelonitrile. Two oxygen molecules are consumed in the conversion of tyrosine to (E)-p-hydroxyphenylacetaldehyde oxime, indicating the existence of a previously undetected hydroxylation step in addition to that resulting in the formation of N-hydroxytyrosine. Radioactively labeled 1-nitro-2-(p-hydroxyphenyl)ethane was chemically synthesized and tested as a possible intermediate. Biosynthetic experiments demonstrate that the microsomal enzyme system metabolizes the nitro compound to the subsequent intermediates in dhurrin synthesis (Km = 0.05 mM; Vmax = 14 nmol/mg of protein/h). Low amounts of 1-nitro-2-(p-hydroxyphenyl)ethane are produced in the microsomal reaction mixtures when tyrosine is used as substrate. These data support the involvement of 1-nitro-2-(p-hydroxyphenyl)ethane or more likely its aci-nitro tautomer as an intermediate between N-hydroxytyrosine and p-hydroxyphenylacetaldehyde oxime. The conversion of (E)-p-hydroxyphenylacetaldehydeoxime to p-hydroxymandelonitrile requires a single oxygen molecule. The oxygen molecule is utilized for hydroxylation of p-hydroxyphenylacetonitrile into p-hydroxymandelonitrile. This indicates that the conversion of p-hydroxyphenylacetaldehyde oxime into p-hydroxyphenylacetonitrile proceeds by a simple dehydration reaction.

  5. The biosynthesis of cyanogenic glucosides in higher plants. The (E)- and (Z)-isomers of p-hydroxyphenylacetaldehyde oxime as intermediates in the biosynthesis of dhurrin in Sorghum bicolor (L. ) Moench

    SciTech Connect

    Halkier, B.A.; Olsen, C.E.; Moller, B.L. )

    1989-11-25

    The biosynthesis of the tyrosine-derived cyanogenic glucoside dhurrin has been studied with a microsomal preparation obtained from etiolated seedlings of sorghum. The biosynthetic pathway involves tyrosine, N-hydroxytyrosine, and p-hydroxyphenylacetaldehyde oxime as early intermediates. The use of deuterium-labeled tyrosine and mass spectrometric analyses demonstrate that the alpha-hydrogen atom of tyrosine is retained in the conversion of tyrosine to p-hydroxyphenylacetaldehyde oxime. This excludes p-hydroxyphenylpyruvic acid oxime as intermediate in the pathway. A high pressure liquid chromatography method was developed to separate the (E)- and (Z)-isomers of p-hydroxyphenylacetaldehyde oxime. The microsomal enzyme system was found to produce initially the (E)-isomer of p-hydroxyphenylacetaldehyde oxime. An isomerase then converts the (E)-isomer to the (Z)-isomer, which is the isomer preferentially utilized by the microsomal enzyme system in the subsequent biosynthetic reactions. The (E)-isomer produced in situ is more efficiently converted to the (Z)-isomer than exogenously added (E)-isomer and may thus be metabolically channeled.

  6. 2-Nitro-3-(p-hydroxyphenyl)propionate and aci-1-nitro-2-(p-hydroxyphenyl)ethane, two intermediates in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor (L. ) Moench

    SciTech Connect

    Halkier, B.A.; Lykkesfeldt, J.; Moller, B.L. )

    1991-01-15

    The biosynthetic pathway for the cyanogenic glucoside dhurrin derived from tyrosine has been studied in vitro by using ({sup 18}O)oxygen and a microsomal enzyme system obtained from etiolated sorghum seedlings. The products formed were purified by HPLC and TLC, and the incorporation of ({sup 18}O)oxygen was monitored by mass spectrometry. In the presence of NADPH and ({sup 18}O)dioxygen, L-tyrosine is converted to (E)- and (Z)-p-hydroxyphenylacetaldhyde oxime with quantitative incorporation of an ({sup 18}O)oxygen atom into the oxime function. These data demonstrate that the conversion of N-hydroxytyrosine to p-hydroxyphenylacetaldehyde oxime involves additional N-hydroxylation and N-oxidation reactions giving rise to the formation of 2-nitro-3-(p-hydroxyphenyl)propionate, which by decarboxylation produces aci-1-nitro-2-(p-hydroxyphenyl)ethane. Both compounds are additional intermediates in the pathway. The two ({sup 18}O)oxygen atoms introduced by the N-hydroxylations are enzymatically distinguishable as demonstrated by the specific loss of the oxygen atom introduced by the first N-hydroxylation reaction in the subsequent conversion of aci-1-nitro-2-(p-hydroxyphenyl)ethane to (E)-p-hydroxyphenylacetaldehyde oxime. A high flux of intermediates through the microsomal enzyme system is obtained with N-hydroxytyrosine as a substrate. This renders the conversion of the aci-nitro compound rate limiting and results in its release from the active site of the enzyme system and accumulation of the tautomeric nitro compound.

  7. A simple analytical method for dhurrin content evaluation in cyanogenic plants for their utilization in fodder and biofumigation.

    PubMed

    De Nicola, Gina Rosalinda; Leoni, Onofrio; Malaguti, Lorena; Bernardi, Roberta; Lazzeri, Luca

    2011-08-10

    Cyanogenic plants have some potential as biocidal green manure crops in limiting several soilborne pests and pathogens. Sorghum (Sorghum bicolor (L.) Moench) and Sudangrass (Sorghum bicolor subsp. sudanense (P.) Stapf), in fact, contain the cyanogenic glucoside p-hydroxy-(S)-mandelonitrile-β-D-glucoside (dhurrin) as a substrate of its secondary defensive system able to release hydrogen cyanide following tissue lesions due to biotic or abiotic factors. Given that dhurrin content is correlated with the biofumigant efficacy of the plants, a high dhurrin content could be a positive character for utilization of sorghum and Sudangrass as biocidal green manure plants. For chemical characterization of the available germplasm, a simple, safe, and accurate method is necessary. In this paper, a new method for dhurrin analysis, based on methanol extraction and high-performance liquid chromatography, is reported and discussed. The feasibility of this analytical procedure was tested by evaluating dhurrin level in roots and stems during cultivation of four different sorghum and Sudangrass varieties in agronomic trials performed in 2008 in the Po valley (Italy). The dhurrin content ranged from 0.16 ± 0.04 to 7.14 ± 0.32 mg g(-1) on dried matter (DM) in stems and from 1.38 ± 0.02 to 6.57 ± 0.09 mg g(-1) on DM in roots, showing statistical differences among the tested germplasms that could be linked to the efficacy of their utilization as biofumigant plants. The method also opens new perspectives for the characterization of sorgum plants as fodder, for which the presence of dhurrin is considered to be negative for its well-known toxicity. PMID:21707058

  8. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways.

    PubMed

    Clausen, Mette; Kannangara, Rubini M; Olsen, Carl E; Blomstedt, Cecilia K; Gleadow, Roslyn M; Jørgensen, Kirsten; Bak, Søren; Motawie, Mohammed S; Møller, Birger Lindberg

    2015-11-01

    The biosynthetic pathway for the cyanogenic glucoside dhurrin in sorghum has previously been shown to involve the sequential production of (E)- and (Z)-p-hydroxyphenylacetaldoxime. In this study we used microsomes prepared from wild-type and mutant sorghum or transiently transformed Nicotiana benthamiana to demonstrate that CYP79A1 catalyzes conversion of tyrosine to (E)-p-hydroxyphenylacetaldoxime whereas CYP71E1 catalyzes conversion of (E)-p-hydroxyphenylacetaldoxime into the corresponding geometrical Z-isomer as required for its dehydration into a nitrile, the next intermediate in cyanogenic glucoside synthesis. Glucosinolate biosynthesis is also initiated by the action of a CYP79 family enzyme, but the next enzyme involved belongs to the CYP83 family. We demonstrate that CYP83B1 from Arabidopsis thaliana cannot convert the (E)-p-hydroxyphenylacetaldoxime to the (Z)-isomer, which blocks the route towards cyanogenic glucoside synthesis. Instead CYP83B1 catalyzes the conversion of the (E)-p-hydroxyphenylacetaldoxime into an S-alkyl-thiohydroximate with retention of the configuration of the E-oxime intermediate in the final glucosinolate core structure. Numerous microbial plant pathogens are able to detoxify Z-oximes but not E-oximes. The CYP79-derived E-oximes may play an important role in plant defense. PMID:26361733

  9. Consequences of transferring three sorghum genes for secondary metabolite (cyanogenic glucoside) biosynthesis to grapevine hairy roots.

    PubMed

    Franks, T K; Powell, K S; Choimes, S; Marsh, E; Iocco, P; Sinclair, B J; Ford, C M; van Heeswijck, R

    2006-04-01

    A multigenic trait (biosynthesis of the secondary metabolite, dhurrin cyanogenic glucoside) was engineered de novo in grapevine (Vitis vinifera L.). This follows a recent report of transfer of the same trait to Arabidopsis (Arabidopsis thaliana) using three genetic sequences from sorghum (Sorghum bicolor): two cytochrome P450-encoding cDNAs (CYP79A1 and CYP71E1) and a UDPG-glucosyltransferase-encoding cDNA (sbHMNGT). Here we describe the two-step process involving whole plant transformation followed by hairy root transformation, which was used to transfer the same three sorghum sequences to grapevine. Transgenic grapevine hairy root lines that accumulated transcript from none, one (sbHMNGT), two (CYP79A1 and CYP71E1) or all three transgenes were recovered and characterisation of these lines provided information about the requirements for dhurrin biosynthesis in grapevine. Only lines that accumulated transcripts from all three transgenes had significantly elevated cyanide potential (up to the equivalent of about 100 mg HCN kg(-1) fresh weight), and levels were highly variable. One dhurrin-positive line was tested and found to release cyanide upon maceration and can therefore be considered 'cyanogenic'. In in vitro dual co-culture of this cyanogenic hairy root line or an acyanogenic line with the specialist root-sucking, gall-forming, aphid-like insect, grapevine phylloxera (Daktulosphaira vitifoliae, Fitch), there was no evidence for protection of the cyanogenic plant tissue from infestation by the insect. Consistently high levels of dhurrin accumulation may be required for this to occur. The possibility that endogenous grapevine gene expression is modulated in response to engineered dhurrin biosynthesis was investigated using microarray analysis of 1225 grapevine ESTs, but differences in patterns of gene expression associated with dhurrin-positive and dhurrin-negative phenotypes were not identified. PMID:16604459

  10. Discovery of a dhurrin QTL in sorghum bicolor: colocalization of dhurrin biosynthesis and a novel stay-green QTL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dhurrin [(S)-p-hydroxymandelonitrile-ß-D-glucopyranoside] is a cyanogenic glucoside produced by (Sorghum bicolor L. Moench) and is generally considered a natural defense compound capable of producing the toxin hydrogen cyanide (HCN) to deter animal herbivory. Recently, high levels of leaf dhurrin h...

  11. Two new cyanogenic glucosides from the leaves of Hydrangea macrophylla.

    PubMed

    Yang, Chun-Juan; Wang, Zhi-Bin; Zhu, Da-Ling; Yu, Ying; Lei, Yin-Ting; Liu, Yan

    2012-01-01

    Chemical investigation of the ethanol extract of the aerial parts of Hydrangea macrophylla collected in the Sichuan Province of China resulted in the isolation of two new cyanogenic glucosides. Their structures were elucidated as [(2R)-2-β-D-glucopyranosyloxy)-2-(3,4-dimethoxy-phenyl)] acetonitrile (1) and {(2R)-2-[α-D-glucopyranosyl(1-->6)β-D-glucopyranosyloxy]-2-(3-hydroxy-4-methoxy-phenyl)}acetonitrile (2) on the basis of extensive spectroscopic analysis (1D, 2D NMR and HRESIMS) and chemical studies. PMID:22569418

  12. Effects of PEG-induced osmotic stress on growth and dhurrin levels of forage sorghum.

    PubMed

    O'Donnell, Natalie H; Møller, Birger Lindberg; Neale, Alan D; Hamill, John D; Blomstedt, Cecilia K; Gleadow, Roslyn M

    2013-12-01

    Sorghum (Sorghum bicolor L. Moench) is a valuable forage crop in regions with low soil moisture. Sorghum may accumulate high concentrations of the cyanogenic glucoside dhurrin when drought stressed resulting in possible cyanide (HCN) intoxication of grazing animals. In addition, high concentrations of nitrate, also potentially toxic to ruminants, may accumulate during or shortly after periods of drought. Little is known about the degree and duration of drought-stress required to induce dhurrin accumulation, or how changes in dhurrin concentration are influenced by plant size or nitrate metabolism. Given that finely regulating soil moisture under controlled conditions is notoriously difficult, we exposed sorghum plants to varying degrees of osmotic stress by growing them for different lengths of time in hydroponic solutions containing polyethylene glycol (PEG). Plants grown in medium containing 20% PEG (-0.5 MPa) for an extended period had significantly higher concentrations of dhurrin in their shoots but lower dhurrin concentrations in their roots. The total amount of dhurrin in the shoots of plants from the various treatments was not significantly different on a per mass basis, although a greater proportion of shoot N was allocated to dhurrin. Following transfer from medium containing 20% PEG to medium lacking PEG, shoot dhurrin concentrations decreased but nitrate concentrations increased to levels potentially toxic to grazing ruminants. This response is likely due to the resumption of plant growth and root activity, increasing the rate of nitrate uptake. Data presented in this article support a role for cyanogenic glucosides in mitigating oxidative stress. PMID:24080394

  13. Ultraperformance liquid chromatography tandem mass spectrometry determination of cyanogenic glucosides in Trifolium species.

    PubMed

    Muzashvili, Tamar; Moniuszko-Szajwaj, Barbara; Pecio, Lukasz; Oleszek, Wieslaw; Stochmal, Anna

    2014-02-26

    Cyanogenic glucosides were analyzed by ultra-high-performance liquid chromatography combined with mass spectrometry in 88 Trifolium species grown at the same site. On the basis of the occurrence of cyanogenic glucosides and the linamarin/lotaustralin ratio species could be grouped into five clusters. Cluster C1 included 37 species, which did not contain cyanogens. Cluster C2 (22 species) included plants containing only lotaustralin. In clusters C3 (14 species), C4 (13 species), and C5 (2 species) both linamarin and lotaustralin were present but at different ratios. In C3 and C4 the linamarin/lotaustralin ratio was below 1, whereas in cluster C5 the ratio was much higher. Generally, the total content of cyanogens was below 500 μg/g dry matter. Only in Trifolium repens var. biasoletti and Trifolium montanum extremely high cyanogen concentrations were observed. There was no general rule of occurrence of cyanogens. Samples of the same species from different countries accumulated cyanogens or could be free of these compounds. PMID:24476020

  14. Sequestration, tissue distribution and developmental transmission of cyanogenic glucosides in a specialist insect herbivore.

    PubMed

    Zagrobelny, Mika; Olsen, Carl Erik; Pentzold, Stefan; Fürstenberg-Hägg, Joel; Jørgensen, Kirsten; Bak, Søren; Møller, Birger Lindberg; Motawia, Mohammed Saddik

    2014-01-01

    Considering the staggering diversity of bioactive natural products present in plants, insects are only able to sequester a small number of phytochemicals from their food plants. The mechanisms of how only some phytochemicals are sequestered and how the sequestration process takes place remains largely unknown. In this study the model system of Zygaena filipendulae (Lepidoptera) and their food plant Lotus corniculatus is used to advance the knowledge of insect sequestration. Z. filipendulae larvae are dependent on sequestration of the cyanogenic glucosides linamarin and lotaustralin from their food plant, and have a much lower fitness if reared on plants without these compounds. This study investigates the fate of the cyanogenic glucosides during ingestion, sequestration in the larvae, and in the course of insect ontogeny. To this purpose, double-labeled linamarin and lotaustralin were chemically synthesized carrying two stable isotopes, a (2)H labeled aglucone and a (13)C labeled glucose moiety. In addition, a small amount of (14)C was incorporated into the glucose residue. The isotope-labeled compounds were applied onto cyanogenic L. corniculatus leaves that were subsequently presented to the Z. filipendulae larvae. Following ingestion by the larvae, the destiny of the isotope labeled cyanogenic glucosides was monitored in different tissues of larvae and adults at selected time points, using radio-TLC and LC-MS analyses. It was shown that sequestered compounds are taken up intact, contrary to earlier hypotheses where it was suggested that the compounds would have to be hydrolyzed before transport across the gut. The uptake from the larval gut was highly stereo selective as the β-glucosides were retained while the α-glucosides were excreted and recovered in the frass. Sequestered compounds were rapidly distributed into all analyzed tissues of the larval body, partly retained throughout metamorphosis and transferred into the adult insect where they were

  15. Metabolism, excretion and avoidance of cyanogenic glucosides in insects with different feeding specialisations.

    PubMed

    Pentzold, Stefan; Zagrobelny, Mika; Bjarnholt, Nanna; Kroymann, Juergen; Vogel, Heiko; Olsen, Carl Erik; Møller, Birger Lindberg; Bak, Søren

    2015-11-01

    Cyanogenic glucosides (CNglcs) are widespread plant defence compounds releasing toxic hydrogen cyanide when hydrolysed by specific β-glucosidases after plant tissue damage. In contrast to specialist herbivores that have mechanisms to avoid toxicity from CNglcs, it is generally assumed that non-adapted herbivores are negatively affected by CNglcs. Recent evidence, however, implies that the defence potential of CNglcs towards herbivores may not be as effective as previously anticipated. Here, performance, metabolism and excretion products of insects not adapted to CNglcs were analysed, including species with different degrees of dietary specialisation (generalists, specialists) and different feeding modes (leaf-snipping lepidopterans, piercing-sucking aphids). Insects were reared either on cyanogenic or acyanogenic plants or on an artificial cyanogenic diet. Lepidopteran generalists (Spodoptera littoralis, Spodoptera exigua, Mamestra brassicae) were compared to lepidopteran glucosinolate-specialists (Pieris rapae, Pieris brassicae, Plutella xylostella), and a generalist aphid (Myzus persicae) was compared to an aphid glucosinolate-specialist (Lipaphis erysimi). All insects were tolerant to cyanogenic plants; in lepidopterans tolerance was mainly due to excretion of intact CNglcs. The two Pieris species furthermore metabolized aromatic CNglcs to amino acid conjugates (Cys, Gly, Ser) and derivatives of these, which is similar to the metabolism of benzylglucosinolates in these species. Aphid species avoided uptake of CNglcs during feeding. Our results imply that non-adapted insects tolerate plant CNglcs either by keeping them intact for excretion, metabolizing them, or avoiding uptake. PMID:26483288

  16. Cyanogen

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS • You are here : EPA Home • Research • Environmental Assessment • IRIS • IRIS Summaries Redirect Page As of September 28 , 2010 , the assessment summary for cyanogen is included in the hydro

  17. A recycling pathway for cyanogenic glycosides evidenced by the comparative metabolic profiling in three cyanogenic plant species.

    PubMed

    Pičmanová, Martina; Neilson, Elizabeth H; Motawia, Mohammed S; Olsen, Carl Erik; Agerbirk, Niels; Gray, Christopher J; Flitsch, Sabine; Meier, Sebastian; Silvestro, Daniele; Jørgensen, Kirsten; Sánchez-Pérez, Raquel; Møller, Birger Lindberg; Bjarnholt, Nanna

    2015-08-01

    Cyanogenic glycosides are phytoanticipins involved in plant defence against herbivores by virtue of their ability to release toxic hydrogen cyanide (HCN) upon tissue disruption. In addition, endogenous turnover of cyanogenic glycosides without the liberation of HCN may offer plants an important source of reduced nitrogen at specific developmental stages. To investigate the presence of putative turnover products of cyanogenic glycosides, comparative metabolic profiling using LC-MS/MS and high resolution MS (HR-MS) complemented by ion-mobility MS was carried out in three cyanogenic plant species: cassava, almond and sorghum. In total, the endogenous formation of 36 different chemical structures related to the cyanogenic glucosides linamarin, lotaustralin, prunasin, amygdalin and dhurrin was discovered, including di- and tri-glycosides derived from these compounds. The relative abundance of the compounds was assessed in different tissues and developmental stages. Based on results common to the three phylogenetically unrelated species, a potential recycling endogenous turnover pathway for cyanogenic glycosides is described in which reduced nitrogen and carbon are recovered for primary metabolism without the liberation of free HCN. Glycosides of amides, carboxylic acids and 'anitriles' derived from cyanogenic glycosides appear as common intermediates in this pathway and may also have individual functions in the plant. The recycling of cyanogenic glycosides and the biological significance of the presence of the turnover products in cyanogenic plants open entirely new insights into the multiplicity of biological roles cyanogenic glycosides may play in plants. PMID:26205491

  18. Dhurrin Synthesis in Sorghum Is Regulated at the Transcriptional Level and Induced by Nitrogen Fertilization in Older Plants1

    PubMed Central

    Busk, Peter Kamp; Møller, Birger Lindberg

    2002-01-01

    The content of the cyanogenic glucoside dhurrin in sorghum (Sorghum bicolor L. Moench) varies depending on plant age and growth conditions. The cyanide potential is highest shortly after onset of germination. At this stage, nitrogen application has no effect on dhurrin content, whereas in older plants, nitrogen application induces an increase. At all stages, the content of dhurrin correlates well with the activity of the two biosynthetic enzymes, CYP79A1 and CYP71E1, and with the protein and mRNA level for the two enzymes. During development, the activity of CYP79A1 is lower than the activity of CYP71E1, suggesting that CYP79A1 catalyzes the rate-limiting step in dhurrin synthesis as has previously been shown using etiolated seedlings. The site of dhurrin synthesis shifts from leaves to stem during plant development. In combination, the results demonstrate that dhurrin content in sorghum is largely determined by transcriptional regulation of the biosynthetic enzymes CYP79A1 and CYP71E1. PMID:12114576

  19. Metabolic consequences of knocking out UGT85B1, the gene encoding the glucosyltransferase required for synthesis of dhurrin in Sorghum bicolor (L. Moench).

    PubMed

    Blomstedt, Cecilia K; O'Donnell, Natalie H; Bjarnholt, Nanna; Neale, Alan D; Hamill, John D; Møller, Birger Lindberg; Gleadow, Roslyn M

    2016-02-01

    Many important food crops produce cyanogenic glucosides as natural defense compounds to protect against herbivory or pathogen attack. It has also been suggested that these nitrogen-based secondary metabolites act as storage reserves of nitrogen. In sorghum, three key genes, CYP79A1, CYP71E1 and UGT85B1, encode two Cytochrome P450s and a glycosyltransferase, respectively, the enzymes essential for synthesis of the cyanogenic glucoside dhurrin. Here, we report the use of targeted induced local lesions in genomes (TILLING) to identify a line with a mutation resulting in a premature stop codon in the N-terminal region of UGT85B1. Plants homozygous for this mutation do not produce dhurrin and are designated tcd2 (totally cyanide deficient 2) mutants. They have reduced vigor, being dwarfed, with poor root development and low fertility. Analysis using liquid chromatography-mass spectrometry (LC-MS) shows that tcd2 mutants accumulate numerous dhurrin pathway-derived metabolites, some of which are similar to those observed in transgenic Arabidopsis expressing the CYP79A1 and CYP71E1 genes. Our results demonstrate that UGT85B1 is essential for formation of dhurrin in sorghum with no co-expressed endogenous UDP-glucosyltransferases able to replace it. The tcd2 mutant suffers from self-intoxication because sorghum does not have a feedback mechanism to inhibit the initial steps of dhurrin biosynthesis when the glucosyltransferase activity required to complete the synthesis of dhurrin is lacking. The LC-MS analyses also revealed the presence of metabolites in the tcd2 mutant which have been suggested to be derived from dhurrin via endogenous pathways for nitrogen recovery, thus indicating which enzymes may be involved in such pathways. PMID:26493517

  20. The multiple strategies of an insect herbivore to overcome plant cyanogenic glucoside defence.

    PubMed

    Pentzold, Stefan; Zagrobelny, Mika; Roelsgaard, Pernille Sølvhøj; Møller, Birger Lindberg; Bak, Søren

    2014-01-01

    Cyanogenic glucosides (CNglcs) are widespread plant defence compounds that release toxic hydrogen cyanide by plant β-glucosidase activity after tissue damage. Specialised insect herbivores have evolved counter strategies and some sequester CNglcs, but the underlying mechanisms to keep CNglcs intact during feeding and digestion are unknown. We show that CNglc-sequestering Zygaena filipendulae larvae combine behavioural, morphological, physiological and biochemical strategies at different time points during feeding and digestion to avoid toxic hydrolysis of the CNglcs present in their Lotus food plant, i.e. cyanogenesis. We found that a high feeding rate limits the time for plant β-glucosidases to hydrolyse CNglcs. Larvae performed leaf-snipping, a minimal disruptive feeding mode that prevents mixing of plant β-glucosidases and CNglcs. Saliva extracts did not inhibit plant cyanogenesis. However, a highly alkaline midgut lumen inhibited the activity of ingested plant β-glucosidases significantly. Moreover, insect β-glucosidases from the saliva and gut tissue did not hydrolyse the CNglcs present in Lotus. The strategies disclosed may also be used by other insect species to overcome CNglc-based plant defence and to sequester these compounds intact. PMID:24625698

  1. Dirigent Protein-Mediated Lignan and Cyanogenic Glucoside Formation in Flax Seed: Integrated Omics and MALDI Mass Spectrometry Imaging.

    PubMed

    Dalisay, Doralyn S; Kim, Kye Won; Lee, Choonseok; Yang, Hong; Rübel, Oliver; Bowen, Benjamin P; Davin, Laurence B; Lewis, Norman G

    2015-06-26

    An integrated omics approach using genomics, transcriptomics, metabolomics (MALDI mass spectrometry imaging, MSI), and bioinformatics was employed to study spatiotemporal formation and deposition of health-protecting polymeric lignans and plant defense cyanogenic glucosides. Intact flax (Linum usitatissimum) capsules and seed tissues at different development stages were analyzed. Transcriptome analyses indicated distinct expression patterns of dirigent protein (DP) gene family members encoding (-)- and (+)-pinoresinol-forming DPs and their associated downstream metabolic processes, respectively, with the former expressed at early seed coat development stages. Genes encoding (+)-pinoresinol-forming DPs were, in contrast, expressed at later development stages. Recombinant DP expression and DP assays also unequivocally established their distinct stereoselective biochemical functions. Using MALDI MSI and ion mobility separation analyses, the pinoresinol downstream derivatives, secoisolariciresinol diglucoside (SDG) and SDG hydroxymethylglutaryl ester, were localized and detectable only in early seed coat development stages. SDG derivatives were then converted into higher molecular weight phenolics during seed coat maturation. By contrast, the plant defense cyanogenic glucosides, the monoglucosides linamarin/lotaustralin, were detected throughout the flax capsule, whereas diglucosides linustatin/neolinustatin only accumulated in endosperm and embryo tissues. A putative biosynthetic pathway to the cyanogens is proposed on the basis of transcriptome coexpression data. Localization of all metabolites was at ca. 20 μm resolution, with the web based tool OpenMSI enabling not only resolution enhancement but also an interactive system for real-time searching for any ion in the tissue under analysis. PMID:25981198

  2. Leaching of cyanogenic glucosides and cyanide from white clover green manure.

    PubMed

    Bjarnholt, Nanna; Laegdsmand, Mette; Hansen, Hans C B; Jacobsen, Ole H; Møller, Birger Lindberg

    2008-06-01

    Use of crops for green manure as a substitute for chemical fertilizers and pesticides is an important approach towards more sustainable agricultural practices. Green manure from white clover is rich in nitrogen but white clover also produces the cyanogenic glucosides (CGs) linamarin and lotaustralin; CGs release toxic hydrogen cyanide (HCN) upon hydrolysis which may be utilized for pest control. We demonstrate that applying CGs in the form of a liquid extract of white clover to large columns of intact agricultural soils can result in leaching of toxic cyanide species to a depth of at least 1m. Although degradation of the CGs during leaching proceeded with half lives in the interval 1.5-35 h depending on soil characteristics, a fraction of the applied CGs (0.9-3.2%) was recovered in the leachate as either CGs or toxic cyanide species. Detoxification of the HCN formed was rapid in soil and leachate from both sandy and loamy soil. However, 30% of the leachate samples exceeded the EU threshold value of 50 micrgl(-1) total cyanide for drinking water and 85% exceeded the US threshold of 5 micrgl(-1) for cyanide chronic ecotoxicity in fresh water. This study demonstrates that even easily degradable natural products present in crop plants as defense compounds pose a threat to the quality of groundwater and surface waters. This aspect needs consideration in assessment of the risk associated with use of crops as green manure to replace chemical fertilizers and pesticides as well as in genetic engineering approaches to design crops with improved pest resistance. PMID:18472138

  3. The evolutionary appearance of non-cyanogenic hydroxynitrile glucosides in the Lotus genus is accompanied by the substrate specialization of paralogous β-glucosidases resulting from a crucial amino acid substitution.

    PubMed

    Lai, Daniela; Abou Hachem, Maher; Robson, Fran; Olsen, Carl Erik; Wang, Trevor L; Møller, Birger L; Takos, Adam M; Rook, Fred

    2014-07-01

    Lotus japonicus, like several other legumes, biosynthesizes the cyanogenic α-hydroxynitrile glucosides lotaustralin and linamarin. Upon tissue disruption these compounds are hydrolysed by a specific β-glucosidase, resulting in the release of hydrogen cyanide. Lotus japonicus also produces the non-cyanogenic γ- and β-hydroxynitrile glucosides rhodiocyanoside A and D using a biosynthetic pathway that branches off from lotaustralin biosynthesis. We previously established that BGD2 is the only β-glucosidase responsible for cyanogenesis in leaves. Here we show that the paralogous BGD4 has the dominant physiological role in rhodiocyanoside degradation. Structural modelling, site-directed mutagenesis and activity assays establish that a glycine residue (G211) in the aglycone binding site of BGD2 is essential for its ability to hydrolyse the endogenous cyanogenic glucosides. The corresponding valine (V211) in BGD4 narrows the active site pocket, resulting in the exclusion of non-flat substrates such as lotaustralin and linamarin, but not of the more planar rhodiocyanosides. Rhodiocyanosides and the BGD4 gene only occur in L. japonicus and a few closely related species associated with the Lotus corniculatus clade within the Lotus genus. This suggests the evolutionary scenario that substrate specialization for rhodiocyanosides evolved from a promiscuous activity of a progenitor cyanogenic β-glucosidase, resembling BGD2, and required no more than a single amino acid substitution. PMID:24861854

  4. Transfer of the cytochrome P450-dependent dhurrin pathway from Sorghum bicolor into Nicotiana tabacum chloroplasts for light-driven synthesis.

    PubMed

    Gnanasekaran, Thiyagarajan; Karcher, Daniel; Nielsen, Agnieszka Zygadlo; Martens, Helle Juel; Ruf, Stephanie; Kroop, Xenia; Olsen, Carl Erik; Motawie, Mohammed Saddik; Pribil, Mathias; Møller, Birger Lindberg; Bock, Ralph; Jensen, Poul Erik

    2016-04-01

    Plant chloroplasts are light-driven cell factories that have great potential to act as a chassis for metabolic engineering applications. Using plant chloroplasts, we demonstrate how photosynthetic reducing power can drive a metabolic pathway to synthesise a bio-active natural product. For this purpose, we stably engineered the dhurrin pathway from Sorghum bicolor into the chloroplasts of Nicotiana tabacum (tobacco). Dhurrin is a cyanogenic glucoside and its synthesis from the amino acid tyrosine is catalysed by two membrane-bound cytochrome P450 enzymes (CYP79A1 and CYP71E1) and a soluble glucosyltransferase (UGT85B1), and is dependent on electron transfer from a P450 oxidoreductase. The entire pathway was introduced into the chloroplast by integrating CYP79A1, CYP71E1, and UGT85B1 into a neutral site of the N. tabacum chloroplast genome. The two P450s and the UGT85B1 were functional when expressed in the chloroplasts and converted endogenous tyrosine into dhurrin using electrons derived directly from the photosynthetic electron transport chain, without the need for the presence of an NADPH-dependent P450 oxidoreductase. The dhurrin produced in the engineered plants amounted to 0.1-0.2% of leaf dry weight compared to 6% in sorghum. The results obtained pave the way for plant P450s involved in the synthesis of economically important compounds to be engineered into the thylakoid membrane of chloroplasts, and demonstrate that their full catalytic cycle can be driven directly by photosynthesis-derived electrons. PMID:26969746

  5. Transfer of the cytochrome P450-dependent dhurrin pathway from Sorghum bicolor into Nicotiana tabacum chloroplasts for light-driven synthesis

    PubMed Central

    Gnanasekaran, Thiyagarajan; Karcher, Daniel; Nielsen, Agnieszka Zygadlo; Martens, Helle Juel; Ruf, Stephanie; Kroop, Xenia; Olsen, Carl Erik; Motawie, Mohammed Saddik; Pribil, Mathias; Møller, Birger Lindberg; Bock, Ralph; Jensen, Poul Erik

    2016-01-01

    Plant chloroplasts are light-driven cell factories that have great potential to act as a chassis for metabolic engineering applications. Using plant chloroplasts, we demonstrate how photosynthetic reducing power can drive a metabolic pathway to synthesise a bio-active natural product. For this purpose, we stably engineered the dhurrin pathway from Sorghum bicolor into the chloroplasts of Nicotiana tabacum (tobacco). Dhurrin is a cyanogenic glucoside and its synthesis from the amino acid tyrosine is catalysed by two membrane-bound cytochrome P450 enzymes (CYP79A1 and CYP71E1) and a soluble glucosyltransferase (UGT85B1), and is dependent on electron transfer from a P450 oxidoreductase. The entire pathway was introduced into the chloroplast by integrating CYP79A1, CYP71E1, and UGT85B1 into a neutral site of the N. tabacum chloroplast genome. The two P450s and the UGT85B1 were functional when expressed in the chloroplasts and converted endogenous tyrosine into dhurrin using electrons derived directly from the photosynthetic electron transport chain, without the need for the presence of an NADPH-dependent P450 oxidoreductase. The dhurrin produced in the engineered plants amounted to 0.1–0.2% of leaf dry weight compared to 6% in sorghum. The results obtained pave the way for plant P450s involved in the synthesis of economically important compounds to be engineered into the thylakoid membrane of chloroplasts, and demonstrate that their full catalytic cycle can be driven directly by photosynthesis-derived electrons. PMID:26969746

  6. Transcriptional regulation of de novo biosynthesis of cyanogenic glucosides throughout the life-cycle of the burnet moth Zygaena filipendulae (Lepidoptera).

    PubMed

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Olsen, Carl Erik; Jørgensen, Kirsten; Møller, Birger Lindberg; Bak, Søren

    2014-06-01

    The six-spotted burnet moth Zygaena filipendulae (Lepidoptera) utilize the two cyanogenic glucosides (CNglcs) linamarin and lotaustralin as deterrents against predators throughout the entire life cycle. CNglcs can be hydrolyzed and bioactivated by β-glucosidases, resulting in the release of toxic hydrogen cyanide. CNglcs are retained through metamorphosis, probably involved in mating communication, and transferred during mating from the male to the female as a nuptial gift. CNglcs can be biosynthesized de novo by Z. filipendulae larvae, but may also be sequestered from their food plant Lotus corniculatus (Fabaceae). These two strategies are tightly linked and adjusted according to the CNglc content and composition of the food plant in order to balance CNglc homeostasis in the larva. In this study, the amounts of CNglcs and transcript levels of the biosynthetic genes were monitored in all life-stages and tissues of Z. filipendulae. During pupation, transcription of the biosynthetic genes is turned off and the CNglc content slowly declines. In females but not males, transcription of the biosynthetic genes is re-activated at the end of pupation. Eggs and embryos do not biosynthesize CNglcs de novo, but are endowed with CNglcs following eclosion of the female. Similarly to larvae, de novo biosynthesis in female adults takes place in the integument from which CNglcs are then transported to other organs. This study demonstrates that Z. filipendulae has evolved the ability to adjust the production of CNglcs throughout its life-cycle for optimal utilization in defense and possibly other metabolic functions, while at the same time avoiding intoxication. PMID:24727026

  7. Cyanogenic Lipids

    PubMed Central

    Selmar, Dirk; Grocholewski, Sabine; Seigler, David S.

    1990-01-01

    Large amounts of cyanogenic lipids (esters of 1 cyano-2-methylprop-2-ene-1-ol with C:20 fatty acids) are stored in the seeds of Ungnadia speciosa. During seedling development, these lipids are completely consumed without liberation of free HCN to the atmosphere. At the same time, cyanogenic glycosides are synthesized, but the total amount is much lower (about 26%) than the quantity of cyanogenic lipids formerly present in the seeds. This large decrease in the total content of cyanogens (HCN-potential) demonstrates that at least 74% of cyanogenic lipids are converted to noncyanogenic compounds. Whether the newly synthesized cyanogenic glycosides are derived directly from cyanogenic lipids or produced by de novo synthesis is still unknown. Based on the utilization of cyanogenic lipids for the synthesis of noncyanogenic compounds, it is concluded that these cyanogens serve as storage for reduced nitrogen. The ecophysiological significance of cyanolipids based on multifunctional aspects is discussed. PMID:16667514

  8. Cytochromes P-450 from cassava (Manihot esculenta Crantz) catalyzing the first steps in the biosynthesis of the cyanogenic glucosides linamarin and lotaustralin. Cloning, functional expression in Pichia pastoris, and substrate specificity of the isolated recombinant enzymes.

    PubMed

    Andersen, M D; Busk, P K; Svendsen, I; Møller, B L

    2000-01-21

    The first committed steps in the biosynthesis of the two cyanogenic glucosides linamarin and lotaustralin in cassava are the conversion of L-valine and L-isoleucine, respectively, to the corresponding oximes. Two full-length cDNA clones that encode cytochromes P-450 catalyzing these reactions have been isolated. The two cassava cytochromes P-450 are 85% identical, share 54% sequence identity to CYP79A1 from sorghum, and have been assigned CYP79D1 and CYP79D2. Functional expression has been achieved using the methylotrophic yeast, Pichia pastoris. The amount of CYP79D1 isolated from 1 liter of P. pastoris culture exceeds the amounts that putatively could be isolated from 22,000 grown-up cassava plants. Each cytochrome P-450 metabolizes L-valine as well as L-isoleucine consistent with the co-occurrence of linamarin and lotaustralin in cassava. CYP79D1 was isolated from P. pastoris. Reconstitution in lipid micelles showed that CYP79D1 has a higher k(c) value with L-valine as substrate than with L-isoleucine, which is consistent with linamarin being the major cyanogenic glucoside in cassava. Both CYP79D1 and CYP79D2 are present in the genome of cassava cultivar MCol22 in agreement with cassava being allotetraploid. CYP79D1 and CYP79D2 are actively transcribed, and production of acyanogenic cassava plants would therefore require down-regulation of both genes. PMID:10636899

  9. Involvement of Cytochrome P-450 in the Biosynthesis of Dhurrin in Sorghum bicolor (L.) Moench 1

    PubMed Central

    Halkier, Barbara Ann; Møller, Birger Lindberg

    1991-01-01

    The biosynthesis of the tyrosine-derived cyanogenic glucoside dhurrin involves N-hydroxytyrosine, (E)- and (Z)-p-hydroxyphenylacetaldehyde oxime, p-hydroxyphenylacetonitrile, and p-hydroxymandelonitrile as intermediates and has been studied in vitro using a microsomal enzyme system obtained from etiolated sorghum (Sorghum bicolor [L.] Moench) seedlings. The biosynthesis is inhibited by carbon monoxide and the inhibition is reversed by 450 nm light demonstrating the involvement of cytochrome P-450. The combined use of two differently prepared microsomal enzyme systems and of tyrosine, p-hydroxyphenylacetaldehyde oxime, and p-hydroxyphenylacetonitrile as substrates identify two cytochrome P-450-dependent monooxygenases: the N-hydroxylase which converts tyrosine into N-hydroxytyrosine and the C-hydroxylase converting p-hydroxyphenylacetonitrile into p-hydroxymandelonitrile. The inhibitory effect of a number of putative cytochrome P-450 inhibitors confirms the involvement of cytochrome P-450. Monospecific polyclonal antibodies raised toward NADPH-cytochrome P-450-reductase isolated from sorghum inhibits the same metabolic conversions as carbon monoxide. No cytochrome P-450-dependent monooxygenase catalyzing an N-hydroxylation reaction has previously been reported in plants. The metabolism of p-hydroxyphenylacetaldehyde oxime is completely dependent on the presence of NADPH and oxygen and results in the production of p-hydroxymandelonitrile with no accumulation of the intermediate p-hydroxyphenylacetonitrile in the reaction mixture. The apparent NADPH and oxygen requirements of the oxime-metabolizing enzyme are identical to those of the succeeding C-hydroxylase converting p-hydroxyphenylacetonitrile to p-hydroxymandelonitrile. Due to the complex kinetics of the microsomal enzyme system, these requirements may not appertain to the oxime-metabolizing enzyme, which may convert p-hydroxyphenylacetaldehyde oxime to p-hydroxyacetonitrile by a simple dehydration. Images

  10. Natural variation in synthesis and catabolism genes influences dhurrin content in sorghum (Sorghum bicolor L. Moench)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cyanogenic glucosides are natural compounds found in over 1,000 species of angiosperms that produce HCN and are deemed undesirable for agricultural use. However, these compounds are important components of primary defensive mechanisms of many plant species. One of the best-studied cyanogenic glucos...

  11. Cyanogen bromide

    Integrated Risk Information System (IRIS)

    Cyanogen bromide ; CASRN 506 - 68 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  12. Tissue Distributions of Dhurrin and of Enzymes Involved in Its Metabolism in Leaves of Sorghum bicolor1

    PubMed Central

    Kojima, Mineo; Poulton, Jonathan E.; Thayer, Susan S.; Conn, Eric E.

    1979-01-01

    The tissue distributions of dhurrin [p-hydroxy-(S)-mandelonitrile-β-d-glucoside] and of enzymes involved in its metabolism have been investigated in leaf blades of light-grown Sorghum bicolor seedlings. Enzymic digestion of these leaves using cellulase has enabled preparations of epidermal and mesophyll protoplasts and bundle sheath strands to be isolated with only minor cross-contamination. Dhurrin was located entirely in the epidermal layers of the leaf blade, whereas the two enzymes responsible for its catabolism, namely dhurrin β-glucosidase and hydroxynitrile lyase, resided almost exclusively in the mesophyll tissue. The final enzyme of dhurrin biosynthesis, uridine diphosphate glucose:p-hydroxymandelonitrile glucosyltransferase, was found in both mesophyll (32% of the total activity of the leaf blade) and epidermal (68%) tissues. The bundle sheath strands did not contain significant amounts of dhurrin or of these enzymes. It was concluded that the separation of dhurrin and its catabolic enzymes in different tissues prevents its large scale hydrolysis under normal physiological conditions. The well documented production of HCN (cyanogenesis), which occurs rapidly on crushing Sorghum leaves, would be expected to proceed when the contents of the ruptured epidermal and mesophyll cells are allowed to mix. Images PMID:16660850

  13. Functional characterization, homology modeling and docking studies of β-glucosidase responsible for bioactivation of cyanogenic hydroxynitrile glucosides from Leucaena leucocephala (subabul).

    PubMed

    Shaik, Noor M; Misra, Anurag; Singh, Somesh; Fatangare, Amol B; Ramakumar, Suryanarayanarao; Rawal, Shuban K; Khan, Bashir M

    2013-02-01

    Glycosyl hydrolase family 1 β-glucosidases are important enzymes that serve many diverse functions in plants including defense, whereby hydrolyzing the defensive compounds such as hydroxynitrile glucosides. A hydroxynitrile glucoside cleaving β-glucosidase gene (Llbglu1) was isolated from Leucaena leucocephala, cloned into pET-28a (+) and expressed in E. coli BL21 (DE3) cells. The recombinant enzyme was purified by Ni-NTA affinity chromatography. The optimal temperature and pH for this β-glucosidase were found to be 45 °C and 4.8, respectively. The purified Llbglu1 enzyme hydrolyzed the synthetic glycosides, pNPGlucoside (pNPGlc) and pNPGalactoside (pNPGal). Also, the enzyme hydrolyzed amygdalin, a hydroxynitrile glycoside and a few of the tested flavonoid and isoflavonoid glucosides. The kinetic parameters K (m) and V (max) were found to be 38.59 μM and 0.8237 μM/mg/min for pNPGlc, whereas for pNPGal the values were observed as 1845 μM and 0.1037 μM/mg/min. In the present study, a three dimensional (3D) model of the Llbglu1 was built by MODELLER software to find out the substrate binding sites and the quality of the model was examined using the program PROCHEK. Docking studies indicated that conserved active site residues are Glu 199, Glu 413, His 153, Asn 198, Val 270, Asn 340, and Trp 462. Docking of rhodiocyanoside A with the modeled Llbglu1 resulted in a binding with free energy change (ΔG) of -5.52 kcal/mol on which basis rhodiocyanoside A could be considered as a potential substrate. PMID:23079707

  14. Quantitation of multiple mycotoxins and cyanogenic glucosides in cassava samples from Tanzania and Rwanda by an LC-MS/MS-based multi-toxin method.

    PubMed

    Sulyok, M; Beed, F; Boni, S; Abass, A; Mukunzi, A; Krska, R

    2015-01-01

    A multi-mycotoxin method based on liquid chromatography/tandem mass spectrometry (LC-MS/MS) was used for a mycotoxin survey in 627 samples of processed cassava collected from different districts across Tanzania and Rwanda after the method performance for this matrix had been determined. Matrix effects as well as extraction efficiencies were found to be similar to most other previously investigated matrices with the exception of distinct matrix effects in the negative ionisation mode for early eluting compounds. Limits of detection were far below the regulatory limits set in the European Union for other types of commodities. Relative standard deviations were generally lower than 10% as determined by replicates spiked on two concentration levels. The sample-to-sample variation of the apparent recoveries was determined for 15 individually spiked samples during three different analytical sequences. The related standard deviation was found to be lower than 15% for most of the investigated compounds, thus confirming the applicability of the method for quantitative analysis. The occurrence of regulated mycotoxins was lower than 10% (with the exception of zearalenone) and the related limits were exceeded only in few samples, which suggests that cassava is a comparatively safe commodity as regards mycotoxins. The most prevalent fungal metabolites were emodin, kojic acid, beauvericin, tryptophol, 3-nitropropionic acid, equisetin, alternariol methylether, monocerin, brevianamide F, tenuazonic acid, zearalenone, chrysophanol, monilifomin, enniatins, apicidin and macrosporin. The related concentrations exceeded 1 mg kg(-1) only in few cases. However, extremely high levels of cyanogenic plant toxins, which had been previously added to the method, were observed in few samples, pointing out the need for improved post-harvest management to decrease the levels of these compounds. PMID:25350522

  15. Mobilization and Utilization of Cyanogenic Glycosides

    PubMed Central

    Selmar, Dirk; Lieberei, Reinhard; Biehl, Böle

    1988-01-01

    In the seeds of Hevea brasiliensis, the cyanogenic monoglucoside linamarin (2-β-d-glucopyranosyloxy-2-methylpropionitrile) is accumulated in the endosperm. After onset of germination, the cyanogenic diglucoside linustatin (2-[6-β-d-glucosyl-β-d-glucopyranosyloxy]-2- methylpropionitrile) is formed and exuded from the endosperm of Hevea seedlings. At the same time the content of cyanogenic monoglucosides decreases. The linustatin-splitting diglucosidase and the β-cyanoalanine synthase that assimilates HCN, exhibit their highest activities in the young seedling at this time. Based on these observations the following pathway for the in vivo mobilization and metabolism of cyanogenic glucosides is proposed: storage of monoglucosides (in the endosperm)—glucosylation—transport of the diglucoside (out of the endosperm into the seedling)—cleavage by diglucosidase—reassimilation of HCN to noncyanogenic compounds. The presence of this pathway demonstrates that cyanogenic glucosides, typical secondary plant products serve in the metabolism of developing plants as N-storage compounds and do not exclusively exhibit protective functions due to their repellent effect. PMID:16665975

  16. Mobilization and utilization of cyanogenic glycosides: the linustatin pathway.

    PubMed

    Selmar, D; Lieberei, R; Biehl, B

    1988-03-01

    In the seeds of Hevea brasiliensis, the cyanogenic monoglucoside linamarin (2-beta-d-glucopyranosyloxy-2-methylpropionitrile) is accumulated in the endosperm. After onset of germination, the cyanogenic diglucoside linustatin (2-[6-beta-d-glucosyl-beta-d-glucopyranosyloxy]-2- methylpropionitrile) is formed and exuded from the endosperm of Hevea seedlings. At the same time the content of cyanogenic monoglucosides decreases. The linustatin-splitting diglucosidase and the beta-cyanoalanine synthase that assimilates HCN, exhibit their highest activities in the young seedling at this time. Based on these observations the following pathway for the in vivo mobilization and metabolism of cyanogenic glucosides is proposed: storage of monoglucosides (in the endosperm)-glucosylation-transport of the diglucoside (out of the endosperm into the seedling)-cleavage by diglucosidase-reassimilation of HCN to noncyanogenic compounds. The presence of this pathway demonstrates that cyanogenic glucosides, typical secondary plant products serve in the metabolism of developing plants as N-storage compounds and do not exclusively exhibit protective functions due to their repellent effect. PMID:16665975

  17. Generation of cyanogen-free transgenic cassava.

    PubMed

    Siritunga, Dimuth; Sayre, Richard T

    2003-07-01

    Cassava ( Manihot esculenta Crantz.) is the major source of calories for subsistence farmers in sub-Saharan Africa. Cassava, however, contains potentially toxic levels of the cyanogenic glucoside, linamarin. The cyanogen content of cassava foods can be reduced to safe levels by maceration, soaking, rinsing and baking; however, short-cut processing techniques can yield toxic food products. Our objective was to eliminate cyanogens from cassava so as to eliminate the need for food processing. To achieve this goal we generated transgenic acyanogenic cassava plants in which the expression of the cytochrome P450 genes ( CYP79D1 and CYP79D2), that catalyze the first-dedicated step in linamarin synthesis, was inhibited. Using a leaf-specific promoter to drive the antisense expression of the CYP79D1/ CYP79D2 genes we observed up to a 94% reduction in leaf linamarin content associated with an inhibition of CYP79D1 and CYP79D2 expression. Importantly, the linamarin content of roots also was reduced by 99% in transgenic plants having between 60 and 94% reduction in leaf linamarin content. Analysis of CYP79D1/ CYP79D2 transcript levels in transgenic roots indicated they were unchanged relative to wild-type plants. These results suggest that linamarin is transported from leaves to roots and that a threshold level of leaf linamarin production is required for transport. PMID:14520563

  18. Turnover of dhurrin in green sorghum seedlings. [Sorghum bicolor

    SciTech Connect

    Adewusi, S.R.A. )

    1990-11-01

    The turnover of dhurrin in green seedlings of Sorghum bicolor (Linn) Moench var Redland x Greenleaf, Sudan 70 has been investigated using glyphosate and pulse-labeling studies with {sup 14}C-tyrosine and ({sup 14}C)shikimic acid. The rate of dhurrin breakdown was 4.8 nanomoles per hour in the shoot and 1.4 nanomoles per hour in the root. The rate of dhurrin accumulation in the shoot of 4- to 5-day-old seedlings was high but decreased with age until at the peak period of dhurrin accumulation, the rates of dhurrin synthesis and breakdown were equal. Using a first order equation (an approximation) the rate of dhurrin synthesis (which equals accumulation plus breakdown rates) was 17.4 nanomoles per hour in the shoot and 4.1 nanomoles per hour in the root. In both tissues, the breakdown rate was between 27 and 34% of their synthetic capacity within the experimental period. Dhurrin synthesis in green sorghum seedlings occurred in both the light and dark photoperiods but was faster in the dark period. The result is discussed in relation to the possible metabolic roles of the turnover.

  19. Reports on the distribution of aromatic cyanogenic glycosides in Australian tropical rainforest tree species of the Lauraceae and Sapindaceae.

    PubMed

    Miller, Rebecca E; Tuck, Kellie L

    2013-08-01

    The aromatic cyanogenic glycosides taxiphyllin [(R)-4-hydroxymandelonitrile β-D-glucoside] and prunasin [(R)-mandelonitrile β-D-glucoside] were identified as the main cyanogenic compounds in tissues of Australian endemic tropical rainforest tree taxa in the Lauraceae and Sapindaceae families, respectively. The tyrosine-derived taxiphyllin was the main cyanogenic glycoside in foliage of Beilschmiedia collina. This is the first reported cyanogenic compound from the Lauraceae. In addition, substantial quantitative variation in the capacity for cyanogenesis was detected in leaves from 40 individuals, with taxiphyllin concentrations ranging from 23 to 1263 μg CN g(-1) dry wt. No acyanogenic individuals were detected. Concentrations of taxiphyllin were, on average, 2.2-fold greater in young leaves than in old leaves. Prunasin was the dominant cyanogenic compound in tissues of Mischocarpus grandissimus (leaves) and Mischocarpus exangulatus (leaves and seed capsule). Better known for cyanolipids in seed oils, this is the first time a phenylalanine-derived cyanogenic glycoside has been reported in the Sapindaceae. The concentrations of prunasin varied widely, over an order of magnitude, among individuals and different tissue types in these species, with the higher concentrations found in seed capsules and young leaves. PMID:23642385

  20. Transgenic approaches for cyanogen reduction in cassava.

    PubMed

    Siritunga, Dimuth; Sayre, Richard

    2007-01-01

    For cassava to become a safe and acceptable crop, it is necessary to reduce the cyanogen levels in cassava foods. While this objective can be achieved by processing procedures, recent findings have shown that it is also possible to achieve it by suppression of cyanogen synthesis or by accelerating cyanogen turnover and volatilization. In 2003, cyanogen-free cultivars were generated by selective inhibition CYP79D1/D2 gene expression. The CYP79D1/D2 enzymes catalyze the first-dedicated step in cyanogen synthesis. Tissue-specific inhibition of CYP79D1/D2 expression in leaves lead to a 99% reduction in root cyanogen levels, indicating that the cyanogenic glycoside, linamarin, is synthesized in leaves and transported to roots. An alternative strategy to the reduce cyanogen content is to enhance cyanogen detoxification and cyanide volatilization during processing. This strategy has the advantage that cyanogen levels in unprocessed roots are not altered, potentially providing protection against herbivory andlor theft. To produce cultivars that promote rapid cyanide volatilization, hydroxynitrile lyase (HNL), which catalyzes the last step in cyanogenesis, was overexpressed in roots. Elevated HNL activity resulted in a 3-fold increase in the rate of cyanogen turnover. Importantly, the cyanogen content of the transformed and wild-type plants was identical, a potential benefit for farmers. PMID:17955993

  1. Lotus japonicus flowers are defended by a cyanogenic β-glucosidase with highly restricted expression to essential reproductive organs.

    PubMed

    Lai, Daniela; Pičmanová, Martina; Abou Hachem, Maher; Motawia, Mohammed Saddik; Olsen, Carl Erik; Møller, Birger Lindberg; Rook, Fred; Takos, Adam M

    2015-09-01

    Flowers and leaves of Lotus japonicus contain α-, β-, and γ-hydroxynitrile glucoside (HNG) defense compounds, which are bioactivated by β-glucosidase enzymes (BGDs). The α-HNGs are referred to as cyanogenic glucosides because their hydrolysis upon tissue disruption leads to release of toxic hydrogen cyanide gas, which can deter herbivore feeding. BGD2 and BGD4 are HNG metabolizing BGD enzymes expressed in leaves. Only BGD2 is able to hydrolyse the α-HNGs. Loss of function mutants of BGD2 are acyanogenic in leaves but fully retain cyanogenesis in flowers pointing to the existence of an alternative cyanogenic BGD in flowers. This enzyme, named BGD3, is identified and characterized in this study. Whereas all floral tissues contain α-HNGs, only those tissues in which BGD3 is expressed, the keel and the enclosed reproductive organs, are cyanogenic. Biochemical analysis, active site architecture molecular modelling, and the observation that L. japonicus accessions lacking cyanogenic flowers contain a non-functional BGD3 gene, all support the key role of BGD3 in floral cyanogenesis. The nectar of L. japonicus flowers was also found to contain HNGs and additionally their diglycosides. The observed specialisation in HNG based defence in L. japonicus flowers is discussed in the context of balancing the attraction of pollinators with the protection of reproductive structures against herbivores. PMID:26249044

  2. Cyanogenic Lipids: Utilization during Seedling Development of Ungnadia speciosa.

    PubMed

    Selmar, D; Grocholewski, S; Seigler, D S

    1990-06-01

    Large amounts of cyanogenic lipids (esters of 1 cyano-2-methylprop-2-ene-1-ol with C:20 fatty acids) are stored in the seeds of Ungnadia speciosa. During seedling development, these lipids are completely consumed without liberation of free HCN to the atmosphere. At the same time, cyanogenic glycosides are synthesized, but the total amount is much lower (about 26%) than the quantity of cyanogenic lipids formerly present in the seeds. This large decrease in the total content of cyanogens (HCN-potential) demonstrates that at least 74% of cyanogenic lipids are converted to noncyanogenic compounds. Whether the newly synthesized cyanogenic glycosides are derived directly from cyanogenic lipids or produced by de novo synthesis is still unknown. Based on the utilization of cyanogenic lipids for the synthesis of noncyanogenic compounds, it is concluded that these cyanogens serve as storage for reduced nitrogen. The ecophysiological significance of cyanolipids based on multifunctional aspects is discussed. PMID:16667514

  3. Male-to-female transfer of 5-hydroxytryptophan glucoside during mating in Zygaena filipendulae (Lepidoptera).

    PubMed

    Zagrobelny, Mika; Motawia, Mohammed Saddik; Olsen, Carl Erik; Bak, Søren; Møller, Birger Lindberg

    2013-11-01

    Zygaena filipendulae accumulates the cyanogenic glucosides linamarin and lotaustralin by larval sequestration from the food plant or de novo biosynthesis. We have previously demonstrated that the Z. filipendulae male transfers linamarin and lotaustralin to the female in the course of mating. In this study we report the additional transfer of 5-hydroxytryptophan glucoside (5-(β-d-glucopyranosyloxy)-L-Tryptophan) from the Z. filipendulae male internal genitalia to the female spermatophore around 5 h into the mating process. 5-Hydroxytryptophan glucoside is present in the virgin male internal genitalia, and production continues during the early phase of mating. Following initiation of 5-hydroxytryptophan glucoside transfer to the female, the amount in male internal genitalia is drastically reduced until after mating where it is slowly replenished. For unambiguous structural identification, 5-hydroxytryptophan glucoside was chemically synthesized and used as an authentic standard. The biological function of 5-hydroxytryptophan glucoside remains to be established, although we have indications that it may be involved in inducing the female to stay in copula and delay egg-laying to prevent re-mating of the female. To our knowledge 5-hydroxytryptophan glucoside has not previously been reported present in animal tissues. PMID:24012995

  4. Dhurrin content relates to sorghum [sorghum bicolor (L.) Moench] seedling growth in marginal soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dhurrin content in leaves of mature sorghum plant is a quantitative measure of the level of pre-and postflowering drought tolerance (Burke et al., 2013). Postflowering drought tolerance in sorghum is linked to the staygreen (delayed senescence) trait (Howarth, 2000; Rosenow et al., 1977) which has ...

  5. Dhurrin content relates to sorghum (Sorghum bicolor (L) Moench) seedling growth in marginal soils.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dhurrin content in leaves of mature sorghum plant is a quantitative measure of the level of pre-and postflowering drought tolerance (Burke et al., 2013). Postflowering drought tolerance in sorghum is linked to the staygreen (delayed senescence) trait (Howarth, 2000; Rosenow et al., 1977) which has b...

  6. A new cyanogenic metabolite in Arabidopsis required for inducible pathogen defence.

    PubMed

    Rajniak, Jakub; Barco, Brenden; Clay, Nicole K; Sattely, Elizabeth S

    2015-09-17

    Thousands of putative biosynthetic genes in Arabidopsis thaliana have no known function, which suggests that there are numerous molecules contributing to plant fitness that have not yet been discovered. Prime among these uncharacterized genes are cytochromes P450 upregulated in response to pathogens. Here we start with a single pathogen-induced P450 (ref. 5), CYP82C2, and use a combination of untargeted metabolomics and coexpression analysis to uncover the complete biosynthetic pathway to 4-hydroxyindole-3-carbonyl nitrile (4-OH-ICN), a previously unknown Arabidopsis metabolite. This metabolite harbours cyanogenic functionality that is unprecedented in plants and exceedingly rare in nature; furthermore, the aryl cyanohydrin intermediate in the 4-OH-ICN pathway reveals a latent capacity for cyanogenic glucoside biosynthesis in Arabidopsis. By expressing 4-OH-ICN biosynthetic enzymes in Saccharomyces cerevisiae and Nicotiana benthamiana, we reconstitute the complete pathway in vitro and in vivo and validate the functions of its enzymes. Arabidopsis 4-OH-ICN pathway mutants show increased susceptibility to the bacterial pathogen Pseudomonas syringae, consistent with a role in inducible pathogen defence. Arabidopsis has been the pre-eminent model system for studying the role of small molecules in plant innate immunity; our results uncover a new branch of indole metabolism distinct from the canonical camalexin pathway, and support a role for this pathway in the Arabidopsis defence response. These results establish a more complete framework for understanding how the model plant Arabidopsis uses small molecules in pathogen defence. PMID:26352477

  7. A new phenolic constituent and a cyanogenic glycoside from Balanophora involucrata (Balanophoraceae).

    PubMed

    She, Gai-Mei; Zhang, Ying-Jun; Yang, Chong-Ren

    2013-06-01

    Balanophora involucrata HOOK.f. & THOMSON (Balanophoraceae) is a parasite plant often growing on the roots of leguminous plants. The whole herb has been used medicinally for the treatment of irregular menstruation, cough, hemoptysis, traumatic injury and bleeding, dizziness and gastralgia in Yunnan Province, China. The 2,2-diphenyl-2-picrylhydrazyl (DPPH) assay on the 60% aq. acetone extract of the fresh whole plant of B. involucrata showed considerable radical-scavenging activity (SC₅₀ 15.3 μg/ml). Further purification on the extract led to the isolation of one new phenolic glycoside, sieboldin-3'-ketocarboxylic acid (1), and one new cyanogenic glycoside, proacacipetalin 6'-O-β-D-glucopyranoside (2), together with 26 known compounds including three 4"-O-galloyl and 2",3"-O-(S)-hexahydroxydiphenoyl (HHDP) derivatives of dihydrochalcone glucosides, seven hydrolyzable tannins, and alkane glycosides. The cyanogenic compound isolated from the Balanophoraceae family for the first time might be a signal molecule between B. involucrata and its hosts. The free-radical-scavenging activity of the isolated compounds was also examined by DPPH assay. PMID:23776023

  8. Diversified glucosinolate metabolism: biosynthesis of hydrogen cyanide and of the hydroxynitrile glucoside alliarinoside in relation to sinigrin metabolism in Alliaria petiolata

    PubMed Central

    Frisch, Tina; Motawia, Mohammed S.; Olsen, Carl E.; Agerbirk, Niels; Møller, Birger L.; Bjarnholt, Nanna

    2015-01-01

    Alliaria petiolata (garlic mustard, Brassicaceae) contains the glucosinolate sinigrin as well as alliarinoside, a γ-hydroxynitrile glucoside structurally related to cyanogenic glucosides. Sinigrin may defend this plant against a broad range of enemies, while alliarinoside confers resistance to specialized (glucosinolate-adapted) herbivores. Hydroxynitrile glucosides and glucosinolates are two classes of specialized metabolites, which generally do not occur in the same plant species. Administration of [UL-14C]-methionine to excised leaves of A. petiolata showed that both alliarinoside and sinigrin were biosynthesized from methionine. The biosynthesis of alliarinoside was shown not to bifurcate from sinigrin biosynthesis at the oxime level in contrast to the general scheme for hydroxynitrile glucoside biosynthesis. Instead, the aglucon of alliarinoside was formed from metabolism of sinigrin in experiments with crude extracts, suggesting a possible biosynthetic pathway in intact cells. Hence, the alliarinoside pathway may represent a route to hydroxynitrile glucoside biosynthesis resulting from convergent evolution. Metabolite profiling by LC-MS showed no evidence of the presence of cyanogenic glucosides in A. petiolata. However, we detected hydrogen cyanide (HCN) release from sinigrin and added thiocyanate ion and benzyl thiocyanate in A. petiolata indicating an enzymatic pathway from glucosinolates via allyl thiocyanate and indole glucosinolate derived thiocyanate ion to HCN. Alliarinoside biosynthesis and HCN release from glucosinolate-derived metabolites expand the range of glucosinolate-related defenses and can be viewed as a third line of defense, with glucosinolates and thiocyanate forming protein being the first and second lines, respectively. PMID:26583022

  9. Cyanogenic glycosides: synthesis, physiology, and phenotypic plasticity.

    PubMed

    Gleadow, Roslyn M; Møller, Birger Lindberg

    2014-01-01

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

  10. Analysis of cyanogens with resorcinol and picrate.

    PubMed

    Drochioiu, Gabi; Arsene, Cecilia; Murariu, Manuela; Oniscu, Corneliu

    2008-11-01

    The total cyanogenic potential of various substrates (flax seed, stones of peach, plum, nectarine and apricot as well as apple seeds, and various model compounds) was investigated by using the acid hydrolysis method, picrate method, and a novel method based on the reaction of cyanide liberated from plants with resorcinol and picrate. The hydrocyanic acid liberated from cyanogens was trapped by using a 1% sodium bicarbonate. Then, 1 ml of extract was mixed with 1 ml of working reagent containing 160 microg of resorcinol, 320 microg of picric acid, and 30 mg of sodium carbonate, and heated on a boiling water bath for 10 min. The absorbance was measured at 488 nm in 1cm glass cuvettes at room temperature. The color system obeys Beer's law in the range of 0-5 microg ml(-1) total HCN. Using model compounds and real samples including replicate analyses on prunasin, the resorcinol method proved to be more accurate, reproducible, and especially more sensitive than the known spectrophotometric methods such as the acid hydrolysis method and the picrate method. PMID:18824068

  11. Phenolics, flavonoids, antioxidant activity and cyanogenic glycosides of organic and mineral-base fertilized cassava tubers.

    PubMed

    Omar, Nur Faezah; Hassan, Siti Aishah; Yusoff, Umi Kalsom; Abdullah, Nur Ashikin Psyquay; Wahab, Puteri Edaroyati Megat; Sinniah, Umarani

    2012-01-01

    A field study was conducted to determine the effect of organic and mineral-based fertilizers on phytochemical contents in the tubers of two cassava varieties. Treatments were arranged in a split plot design with three replicates. The main plot was fertilizer source (vermicompost, empty fruit bunch compost and inorganic fertilizer) and sub-plot was cassava variety (Medan and Sri Pontian). The amount of fertilizer applied was based on 180 kg K(2)O ha-1. The tubers were harvested and analyzed for total flavonoids, total phenolics, antioxidant activity and cyanogenic glucoside content. Total phenolic and flavonoid compounds were determined using the Folin-Ciocalteu assay and aluminium chloride colorimetric method, respectively. Different sources of fertilizer, varieties and their interactions were found to have a significant effect on phytochemical content. The phenolic and flavonoid content were significantly higher (p < 0.01) in the vermicompost treatment compared to mineral fertilizer and EFB compost. The total flavonoids and phenolics content of vermicompost treated plants were 39% and 38% higher, respectively, than those chemically fertilized. The antioxidant activity determined using the DPPH and FRAP assays were high with application of organic fertilizer. Cyanogenic glycoside levels were decreased with the application of organic fertilizer. Among the two types of compost, vermicompost resulted in higher nutritional value of cassava tubers. Medan variety with application of vermicompost showed the most promising nutritional quality. Since the nutritional quality of cassava can be improved by organic fertilization, organic fertilizer should be used in place of chemical fertilizer for environmentally sustainable production of better quality cassava. PMID:22370524

  12. A new cyanogenic metabolite in Arabidopsis required for inducible pathogen defense

    PubMed Central

    Rajniak, Jakub; Barco, Brenden; Clay, Nicole K.; Sattely, Elizabeth S.

    2015-01-01

    SUMMARY Thousands of putative biosynthetic genes in Arabidopsis thaliana have no known function, suggesting that there are numerous molecules contributing to plant fitness that have not yet been discovered1,2. Prime among these uncharacterized genes are cytochromes P450 upregulated in response to pathogens3,4. Starting with a single pathogen-induced P4505, CYP82C2, we used a combination of untargeted metabolomics and co-expression analysis to uncover the complete biosynthetic pathway to a previously unknown Arabidopsis metabolite, 4-hydroxyindole-3-carbonyl nitrile (4-OH-ICN), which harbors cyanogenic functionality that is unprecedented in plants and exceedingly rare in nature6,7. The aryl cyanohydrin intermediate in the 4-OH-ICN pathway reveals a latent capacity for cyanogenic glucoside biosynthesis8,9 in Arabidopsis. By expressing 4-OH-ICN biosynthetic enzymes in Saccharomyces cerevisiae and Nicotiana benthamiana, we reconstitute the complete pathway in vitro and in vivo and validate the functions of its enzymes. 4-OH-ICN pathway mutants show increased susceptibility to the bacterial pathogen Pseudomonas syringae, consistent with a role in inducible pathogen defense. Arabidopsis has been the preeminent model system10,11 for studying the role of small molecules in plant innate immunity12; our results uncover a new branch of indole metabolism distinct from the canonical camalexin pathway, and support a role for this pathway in the Arabidopsis defense response.13 These results establish a more complete framework for understanding how the model plant Arabidopsis uses small molecules in pathogen defense. PMID:26352477

  13. Phenolic glucosides from Hasseltia floribunda.

    PubMed

    Dagvadorj, Enkhmaa; Shaker, Kamel H; Windsor, Donald; Schneider, Bernd; Boland, Wilhelm

    2010-11-01

    The leaves of Hasseltia floribunda were examined for their chemical constituents. Twelve phenolic glucosides, namely three hydroxycyclohexenyl acyl glucosides, four acylated salicortin derivatives, and five coumaroyl salicin derivatives, were isolated along with eight known phenolic glycosides, six known flavones, and two known sesquiterpenoid cyclohexenone derivatives. The structures of the isolated compounds were elucidated by NMR spectroscopic and HRMS spectrometric methods and by comparing analytical data with those of related structures. PMID:20822782

  14. Formation of cyanogen iodide by lactoperoxidase.

    PubMed

    Schlorke, Denise; Flemmig, Jörg; Birkemeyer, Claudia; Arnhold, Jürgen

    2016-01-01

    The haem protein lactoperoxidase (LPO) is an important component of the anti-microbial immune defence in external secretions and is also applied as preservative in food, oral care and cosmetic products. Upon oxidation of SCN(-) and I(-) by the LPO-hydrogen peroxide system, oxidised species are formed with bacteriostatic and/or bactericidal activity. Here we describe the formation of the inter(pseudo)halogen cyanogen iodide (ICN) by LPO. This product is formed when both, thiocyanate and iodide, are present together in the reaction mixture. Using (13)C nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry we could identify this inter(pseudo)halogen after applying iodide in slight excess over thiocyanate. The formation of ICN is based on the reaction of oxidised iodine species with thiocyanate. Further, we could demonstrate that ICN is also formed by the related haem enzyme myeloperoxidase and, in lower amounts, in the enzyme-free system. As I(-) is not competitive for SCN(-) under physiologically relevant conditions, the formation of ICN is not expected in secretions but may be relevant for LPO-containing products. PMID:26580225

  15. Conduritol F glucosides and terpenoid glucosides from Cynanchum liukiuense and distribution of conduritol F glucosides in several Asclepiadaceous plants.

    PubMed

    Abe, F; Yamauchi, T; Honda, K; Hayashl, N

    2000-07-01

    Conduritol F 3-0- and 4-O-glucosides were obtained from Cynanchum liukiuense, along with conduritol F which was identified in all Asclepiadaceous plants examined, Tylophora tanakae, Asclepias curassavica and A. fruticosa, as well as in Marsdenia tomentosa. The pattern of the glucosidic linkage to conduritol F differed between individual species, 2-O-glucoside from T tanakae and M. tomentosa, 3-O-glucoside from A. curassavica, but none from A. fruticosa. Along with conduritol F glucosides, an 11-glucosyloxy-megastigmane and a monoterpenoid glucoside were isolated from C. liukiuense. PMID:10923848

  16. Engineering cyanogen synthesis and turnover in cassava (Manihot esculenta).

    PubMed

    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

  17. Cyanogen induced phosphorylation of D-fructose. [prebiotic modeling

    NASA Technical Reports Server (NTRS)

    Degani, CH.; Kawatsuji, M.; Halmann, M.

    1975-01-01

    It has been demonstrated that a phosphorylated sugar, identified as alpha-D-fructopyranose, can be formed as the result of cyanogen-induced phosphorylation of D-fructose at pH 8.8. The product was isolated from barium and cyclohexylammonium salts and identified on the basis of its chromatographic and electrophoretic properties, its lability to hydrolysis by alkaline phosphatase, the rate of its acid-catalyzed hydrolysis, and the results of periodate oxidation and optical rotatory measurements. These results support the suggestion that the cyanogen-induced phosphorylation of free sugars could be a possible process for formation of sugar phosphates under prebiotic conditions (Halman et al., 1969).

  18. Occurrence of sarmentosin and other hydroxynitrile glucosides in Parnassius (papilionidae) butterflies and their food plants.

    PubMed

    Bjarnholt, Nanna; Nakonieczny, Mirosław; Kędziorski, Andrzej; Debinski, Diane M; Matter, Stephen F; Olsen, Carl Erik; Zagrobelny, Mika

    2012-05-01

    Sequestration of plant secondary metabolites is a widespread phenomenon among aposematic insects. Sarmentosin is an unsaturated γ-hydroxynitrile glucoside known from plants and some Lepidoptera. It is structurally and biosynthetically closely related to cyanogenic glucosides, which are commonly sequestered from food plants and/or de novo synthesized by lepidopteran species. Sarmentosin was found previously in Parnassius (Papilionidae) butterflies, but it was not known how the occurrence was related to food plants or whether Parnassius species could biosynthesize the compound. Here, we report on the occurrence of sarmentosin and related compounds in four different Parnassius species belonging to two different clades, as well as their known and suspected food plants. There were dramatic differences between the two clades, with P. apollo and P. smintheus from the Apollo group containing high amounts of sarmentosin, and P. clodius and P. mnemosyne from the Mnemosyne group containing low or no detectable amounts. This was reflected in the larval food plants; P. apollo and P. smintheus larvae feed on Sedum species (Crassulaceae), which all contained considerable amounts of sarmentosin, while the known food plants of the two other species, Dicentra and Corydalis (Fumariaceae), had no detectable levels of sarmentosin. All insects and plants containing sarmentosin also contained other biosynthetically related hydroxynitrile glucosides in patterns previously reported for plants, but not for insects. Not all findings could be explained by sequestration alone and we therefore hypothesize that Parnassius species are able to de novo synthesize sarmentosin. PMID:22527055

  19. Determination of cyanogenic compounds in edible plants by ion chromatography.

    PubMed

    Cho, Hye-Jeon; Do, Byung-Kyung; Shim, Soon-Mi; Kwon, Hoonjeong; Lee, Dong-Ha; Nah, Ahn-Hee; Choi, Youn-Ju; Lee, Sook-Yeon

    2013-06-01

    Cyanogenic glycosides are HCN-producing phytotoxins; HCN is a powerful and a rapidly acting poison. It is not difficult to find plants containing these compounds in the food supply and/or in medicinal herb collections. The objective of this study was to investigate the distribution of total cyanide in nine genera (Dolichos, Ginkgo, Hordeum, Linum, Phaseolus, Prunus, Phyllostachys, Phytolacca, and Portulaca) of edible plants and the effect of the processing on cyanide concentration. Total cyanide content was measured by ion chromatography following acid hydrolysis and distillation. Kernels of Prunus genus are used medicinally, but they possess the highest level of total cyanide of up to 2259.81 CN(-)/g dry weight. Trace amounts of cyanogenic compounds were detected in foodstuffs such as mungbeans and bamboo shoots. Currently, except for the WHO guideline for cassava, there is no global standard for the allowed amount of cyanogenic compounds in foodstuffs. However, our data emphasize the need for the guidelines if plants containing cyanogenic glycosidesare to be developed as dietary supplements. PMID:24278641

  20. Forward Genetics by Genome Sequencing Reveals That Rapid Cyanide Release Deters Insect Herbivory of Sorghum bicolor

    PubMed Central

    Krothapalli, Kartikeya; Buescher, Elizabeth M.; Li, Xu; Brown, Elliot; Chapple, Clint; Dilkes, Brian P.; Tuinstra, Mitchell R.

    2013-01-01

    Whole genome sequencing has allowed rapid progress in the application of forward genetics in model species. In this study, we demonstrated an application of next-generation sequencing for forward genetics in a complex crop genome. We sequenced an ethyl methanesulfonate-induced mutant of Sorghum bicolor defective in hydrogen cyanide release and identified the causal mutation. A workflow identified the causal polymorphism relative to the reference BTx623 genome by integrating data from single nucleotide polymorphism identification, prior information about candidate gene(s) implicated in cyanogenesis, mutation spectra, and polymorphisms likely to affect phenotypic changes. A point mutation resulting in a premature stop codon in the coding sequence of dhurrinase2, which encodes a protein involved in the dhurrin catabolic pathway, was responsible for the acyanogenic phenotype. Cyanogenic glucosides are not cyanogenic compounds but their cyanohydrins derivatives do release cyanide. The mutant accumulated the glucoside, dhurrin, but failed to efficiently release cyanide upon tissue disruption. Thus, we tested the effects of cyanide release on insect herbivory in a genetic background in which accumulation of cyanogenic glucoside is unchanged. Insect preference choice experiments and herbivory measurements demonstrate a deterrent effect of cyanide release capacity, even in the presence of wild-type levels of cyanogenic glucoside accumulation. Our gene cloning method substantiates the value of (1) a sequenced genome, (2) a strongly penetrant and easily measurable phenotype, and (3) a workflow to pinpoint a causal mutation in crop genomes and accelerate in the discovery of gene function in the postgenomic era. PMID:23893483

  1. Overexpression of hydroxynitrile lyase in cassava roots elevates protein and free amino acids while reducing residual cyanogen levels.

    PubMed

    Narayanan, Narayanan N; Ihemere, Uzoma; Ellery, Claire; Sayre, Richard T

    2011-01-01

    Cassava is the major source of calories for more than 250 million Sub-Saharan Africans, however, it has the lowest protein-to-energy ratio of any major staple food crop in the world. A cassava-based diet provides less than 30% of the minimum daily requirement for protein. Moreover, both leaves and roots contain potentially toxic levels of cyanogenic glucosides. The major cyanogen in cassava is linamarin which is stored in the vacuole. Upon tissue disruption linamarin is deglycosylated by the apolplastic enzyme, linamarase, producing acetone cyanohydrin. Acetone cyanohydrin can spontaneously decompose at pHs >5.0 or temperatures >35°C, or is enzymatically broken down by hydroxynitrile lyase (HNL) to produce acetone and free cyanide which is then volatilized. Unlike leaves, cassava roots have little HNL activity. The lack of HNL activity in roots is associated with the accumulation of potentially toxic levels of acetone cyanohydrin in poorly processed roots. We hypothesized that the over-expression of HNL in cassava roots under the control of a root-specific, patatin promoter would not only accelerate cyanogenesis during food processing, resulting in a safer food product, but lead to increased root protein levels since HNL is sequestered in the cell wall. Transgenic lines expressing a patatin-driven HNL gene construct exhibited a 2-20 fold increase in relative HNL mRNA levels in roots when compared with wild type resulting in a threefold increase in total root protein in 7 month old plants. After food processing, HNL overexpressing lines had substantially reduced acetone cyanohydrin and cyanide levels in roots relative to wild-type roots. Furthermore, steady state linamarin levels in intact tissues were reduced by 80% in transgenic cassava roots. These results suggest that enhanced linamarin metabolism contributed to the elevated root protein levels. PMID:21799761

  2. Acute toxicity of cyanogen chloride to Daphnia magna

    SciTech Connect

    Kononen, D.W.

    1988-09-01

    The destruction of cyanide in waste waters by chlorination has been shown to result in the formation of the extremely toxic compound, cyanogen chloride. Industrial cyanide-containing waste waters may be treated by a batch chlorination process under highly alkaline conditions prior to being discharged into a receiving water systems. Alternatively, if the concentration of cyanide is relatively low, and such waste waters may be diverted to municipal waste treatment facilities where they may be subjected to a process of chlorination which may not be sufficient for the complete oxidative destruction of the available cyanide. Although a large body of literature exists concerning the toxicity of HCN and metallic cyanide compounds to aquatic organisms, there is a comparative scarcity of information concerning cyanogen chloride toxicity. This study was designed to determine the acute toxicity of CNCl to Daphnia magna neonates under static bioassay conditions.

  3. Coevolution of Cyanogenic Bamboos and Bamboo Lemurs on Madagascar

    PubMed Central

    Ballhorn, Daniel J.; Rakotoarivelo, Fanny Patrika; Kautz, Stefanie

    2016-01-01

    Feeding strategies of specialist herbivores often originate from the coevolutionary arms race of plant defenses and counter-adaptations of herbivores. The interaction between bamboo lemurs and cyanogenic bamboos on Madagascar represents a unique system to study diffuse coevolutionary processes between mammalian herbivores and plant defenses. Bamboo lemurs have different degrees of dietary specialization while bamboos show different levels of chemical defense. In this study, we found variation in cyanogenic potential (HCNp) and nutritive characteristics among five sympatric bamboo species in the Ranomafana area, southeastern Madagascar. The HCNp ranged from 209±72 μmol cyanide*g-1 dwt in Cathariostachys madagascariensis to no cyanide in Bambusa madagascariensis. Among three sympatric bamboo lemur species, the greater bamboo lemur (Prolemur simus) has the narrowest food range as it almost exclusively feeds on the highly cyanogenic C. madagascariensis. Our data suggest that high HCNp is the derived state in bamboos. The ancestral state of lemurs is most likely "generalist" while the ancestral state of bamboo lemurs was determined as equivocal. Nevertheless, as recent bamboo lemurs comprise several "facultative specialists" and only one "obligate specialist" adaptive radiation due to increased flexibility is likely. We propose that escaping a strict food plant specialization enabled facultative specialist bamboo lemurs to inhabit diverse geographical areas. PMID:27532127

  4. Coevolution of Cyanogenic Bamboos and Bamboo Lemurs on Madagascar.

    PubMed

    Ballhorn, Daniel J; Rakotoarivelo, Fanny Patrika; Kautz, Stefanie

    2016-01-01

    Feeding strategies of specialist herbivores often originate from the coevolutionary arms race of plant defenses and counter-adaptations of herbivores. The interaction between bamboo lemurs and cyanogenic bamboos on Madagascar represents a unique system to study diffuse coevolutionary processes between mammalian herbivores and plant defenses. Bamboo lemurs have different degrees of dietary specialization while bamboos show different levels of chemical defense. In this study, we found variation in cyanogenic potential (HCNp) and nutritive characteristics among five sympatric bamboo species in the Ranomafana area, southeastern Madagascar. The HCNp ranged from 209±72 μmol cyanide*g-1 dwt in Cathariostachys madagascariensis to no cyanide in Bambusa madagascariensis. Among three sympatric bamboo lemur species, the greater bamboo lemur (Prolemur simus) has the narrowest food range as it almost exclusively feeds on the highly cyanogenic C. madagascariensis. Our data suggest that high HCNp is the derived state in bamboos. The ancestral state of lemurs is most likely "generalist" while the ancestral state of bamboo lemurs was determined as equivocal. Nevertheless, as recent bamboo lemurs comprise several "facultative specialists" and only one "obligate specialist" adaptive radiation due to increased flexibility is likely. We propose that escaping a strict food plant specialization enabled facultative specialist bamboo lemurs to inhabit diverse geographical areas. PMID:27532127

  5. Sorghum recombinant inbred lines segregating for stay-green QTL's and leaf dhurrin content show differential reaction to stalk rot diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The association between post-flowering drought tolerance and the stay-green phenotype in sorghum is well established. More recent studies link the stay-green phenotype with levels of dhurrin and soluble sugars in the leaves. Post-flowering drought response has always been associated with stalk rot r...

  6. Cucurbitacin glucosides from Citrullus colocynthis.

    PubMed

    Nayab, Durey; Ali, Dildar; Arshad, Nuzhat; Malik, Abdul; Choudhary, M Iqbal; Ahmed, Zaheer

    2006-05-10

    A new cucurbitacin glucoside 2-O-beta-D-glucopyranosyl-16alpha-20R-dihydroxy-cucurbita-1,5,23E,25(26)-tetraen-3,11,22-trione (1) has been isolated from the methanolic extract of the fruits of Citrulluscolocynthis. The structure has been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition 2-O-beta-D-glucopyranosyl-cucurbitacin B (arvenin I) (2) and 2,25-di-O-beta-D-glucopyranosyl-cucurbitacin L (3) are reported for the first time from this species. PMID:16644537

  7. A new isoflavone glucoside from Pterocarpus santalinus.

    PubMed

    Krishnaveni, K S; Srinivasa Rao, J V

    2000-01-01

    A new isoflavone glucoside (1) together with the known santal has been isolated from the heartwood of Pterocarpus santalinus. Based on spectral methods, the structure of the new compound was elucidated as 4',5-dihydroxy 7-O-methyl isoflavone 3'-O-beta-D-glucoside. PMID:11256696

  8. Geospatial association of endemicity of ataxic polyneuropathy and highly cyanogenic cassava cultivars

    PubMed Central

    2013-01-01

    Background Exposure to cyanide from cassava foods is present in communities where ataxic polyneuropathy is endemic. Ataxic polyneuropathy is endemic in coastal parts of southwest and southeast Nigeria, and coastal Newala, south India, but it has been reported in epidemic or endemic forms from Africa, Asia, or Caribbean. This study was done to determine if cyanogenicity of cassava cultivars is higher in lowland than highland areas, and if areas of endemicity of ataxic polyneuropathy colocalize with areas of highest cyanogenicity of cassava. Methods Roots of cassava cultivars were collected from 150 farmers in 32 of 37 administrative areas in Nigeria. Global positioning system was used to determine the location of the roots. Roots were assayed for concentrations of cyanogens. Thin Plate Spline regression was used to produce the contour map of cyanogenicity of the study area. Contour maps of altitude of the endemic areas were produced. Relationship of cyanogenicity of cassava cultivars and altitude, and of locations of areas of high cyanogenicity and areas of endemicity were determined. Results Geometrical mean (95% CI) cyanogen concentration was 182 (142–233) mg HCN eq/kg dry wt for cassava cultivars in areas ≤ 25 m above sea level, but 54 (43–66) mg HCN eq/kg dry wt for areas > 375 m. Non-spatial linear regression of altitude on logarithm transformed concentrations of cyanogens showed highly significant association, (p < 0.0001). Contour map of concentrations of cyanogens in cassava cultivars in Nigeria showed four areas with average concentrations of cassava cyanogens > 250 mg HCN eq/kg dry wt, and one area of moderately high cyanogen concentration > 150 mg HCN eq/kg dry wt. The endemic areas colocalized with areas of highest cassava cyanogenicity in lowland areas close to the Atlantic Ocean. Conclusion This study shows strong geospatial association of areas of endemicity of ataxic polyneuropathy and areas of highest cyanogenicity of

  9. Allosteric indicator displacement enzyme assay for a cyanogenic glycoside.

    PubMed

    Jose, D Amilan; Elstner, Martin; Schiller, Alexander

    2013-10-18

    Indicator displacement assays (IDAs) represent an elegant approach in supramolecular analytical chemistry. Herein, we report a chemical biosensor for the selective detection of the cyanogenic glycoside amygdalin in aqueous solution. The hybrid sensor consists of the enzyme β-glucosidase and a boronic acid appended viologen together with a fluorescent reporter dye. β-Glucosidase degrades the cyanogenic glycoside amygdalin into hydrogen cyanide, glucose, and benzaldehyde. Only the released cyanide binds at the allosteric site of the receptor (boronic acid) thereby inducing changes in the affinity of a formerly bound fluorescent indicator dye at the other side of the receptor. Thus, the sensing probe performs as allosteric indicator displacement assay (AIDA) for cyanide in water. Interference studies with inorganic anions and glucose revealed that cyanide is solely responsible for the change in the fluorescent signal. DFT calculations on a model compound revealed a 1:1 binding ratio of the boronic acid and cyanide ion. The fluorescent enzyme assay for β-glucosidase uses amygdalin as natural substrate and allows measuring Michaelis-Menten kinetics in microtiter plates. The allosteric indicator displacement assay (AIDA) probe can also be used to detect cyanide traces in commercial amygdalin samples. PMID:24123550

  10. Transition of phenolics and cyanogenic glycosides from apricot and cherry fruit kernels into liqueur.

    PubMed

    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. PMID:26948641

  11. Chemisorption of cyanogen chloride by spinel ferrite magnetic nanoparticles.

    PubMed

    Glover, T Grant; DeCoste, Jared B; Sabo, Daniel; Zhang, Z John

    2013-05-01

    Spinel ferrite magnetic nanoparticles, MnFe2O4, NiFe2O4, and CoFe2O4, were synthesized and used as gas-phase adsorbents for the removal of cyanogen chloride from dry air. Fixed-bed adsorption breakthrough experiments show adsorption wave behavior at the leading edge of the breakthrough curve that is not typical of physically adsorbed species. Fourier transform infrared spectroscopy (FTIR) results indicate that CK is reacting with the spinel ferrite surface and forming a carbamate species. The reaction is shown to be a function of the hydroxyl groups and adsorbed water on the surface of the particles as well as the metallic composition of the particles. The surface reaction decreases the remnant and saturation magnetism of the MnFe2O4 and CoFe2O4 particles by approximately 25%. PMID:23540752

  12. Synthesis and Characterization of Hapten-Protein Conjugates for Antibody Production against Cyanogenic Glycosides.

    PubMed

    Bolarinwa, Islamiyat Folashade

    2015-07-01

    Consumption of cyanogenic plants can cause serious health problems for humans. The ability to detect and quantify cyanogenic glycosides, capable of generating cyanide, could contribute to prevention of cyanide poisoning from the consumption of improperly processed cyanogenic plants. Hapten-protein conjugates were synthesized with amygdalin and linamarin by using a novel approach. Polyclonal antibodies were generated by immunizing four New Zealand White rabbits with synthesized amygdalin-bovine serum albumin and linamarin-bovine serum albumin immunogen. This is the first time an antibody was produced against linamarin. Antibody titer curves were obtained from all the four rabbits by using a noncompetitive enzyme-linked immunosorbent assay. High antibody titer was obtained at dilutions greater than 1:50,000 from both immunogens. This new method is an important step forward in preventing ingestion of toxic cyanogenic glycosides. PMID:26197297

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

    NASA Astrophysics Data System (ADS)

    Cardoso, Márcio Zikán; Gilbert, Lawrence E.

    2007-01-01

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

  14. A modified ninhydrin micro-assay for determination of total cyanogens in plants.

    PubMed

    Surleva, Andriana; Drochioiu, Gabi

    2013-12-01

    Indirect quantification of total cyanogenic compounds (cyanogens) in plants was studied using a novel ninhydrin-based spectrophotometric micromethod. The ninhydrin-cyanide system obeys Beer's law in the range from 20 μg L(-1) to 800 μg L(-1) CN(-) with molar absorptivity ε=1.4×10(5) L mol(-1)cm(-1). Recovery at 100 μg L(-1) CN(-) was 100.5±0.1% and LOD and LOQ were 8 and 22 μg L(-1), respectively. The conditions for ninhydrin reagent preparation were discussed. The extraction and separation solutions, extraction and incubation time, and solvent volume were also investigated for maximum recovery of total cyanogens. 0.1% NaHCO3 was used as an extraction solvent for cyanide formed after enzymatic hydrolysis of cyanogens. The procedure was suitable for samples containing more than 90 mg CN(-)/100 g sample. When cyanogen concentrations were lower, the resulted cyanide was separated by microdiffusion in a Conway cell. Water was used as a hydrolysis medium and a donor solvent, while 2% Na2CO3 as an absorbing solution. Total cyanogen content in plum and almond kernels, as well as apple and flax seeds was determined. PMID:23871025

  15. Identification of essential active-site residues in the cyanogenic beta-glucosidase (linamarase) from cassava (Manihot esculenta Crantz) by site-directed mutagenesis.

    PubMed Central

    Keresztessy, Z; Brown, K; Dunn, M A; Hughes, M A

    2001-01-01

    The coding sequence of the mature cyanogenic beta-glucosidase (beta-glucoside glucohydrolase, EC 3.2.1.21; linamarase) was cloned into the vector pYX243 modified to contain the SUC2 yeast secretion signal sequence and expressed in Saccharomyces cerevisiae. The recombinant enzyme is active, glycosylated and showed similar stability to the plant protein. Michaelis constants for hydrolysis of the natural substrate, linamarin (K(m)=1.06 mM) and the synthetic p-nitrophenyl beta-D-glucopyranoside (PNP-Glc; K(m)=0.36 mM), as well as apparent pK(a) values of the free enzyme and the enzyme-substrate complexes (pK(E)(1)=4.4-4.8, pK(E)(2)=6.7-7.2, pK(ES)(1)=3.9-4.4, pK(ES)(2)=8.3) were very similar to those of the plant enzyme. Site-directed mutagenesis was carried out to study the function of active-site residues based on a homology model generated for the enzyme using the MODELLER program. Changing Glu-413 to Gly destroyed enzyme activity, consistent with it being the catalytic nucleophile. The Gln-339Glu mutation also abolished activity, confirming a function in positioning the catalytic diad. The Ala-201Val mutation shifted the pK(a) of the acid/base catalyst Glu-198 from 7.22 to 7.44, reflecting a change in its hydrophobic environment. A Phe-269Asn change increased K(m) for linamarin hydrolysis 16-fold (16.1 mM) and that for PNP-Glc only 2.5-fold (0.84 mM), demonstrating that Phe-269 contributes to the cyanogenic specificity of the cassava beta-glucosidase. PMID:11139381

  16. Two new iridoid glucosides from Hedyotis diffusa.

    PubMed

    Zhang, Yongyong; Chen, Yan; Fan, Chunlin; Ye, Wencai; Luo, Jiabo

    2010-09-01

    Two new iridoid glucosides, named diffusosides A and B, were isolated from the aerial part of Hedyotis diffusa Willd. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis and HRESIMS. These two compounds showed no cytotoxic activity against SMMC-7721, SW480, SW620, Bel7402, and HepG2 cells. PMID:20080156

  17. Cytogenetic activity of the coumarin glucoside seseloside

    SciTech Connect

    Arshava, E.A.

    1986-05-01

    The cytogenetic effect of the coumarin glucoside seseloside on plant objects was studied. It was established that low concentrations of the preparation (from 1 x 10/sup -5/ to 1 x 10/sup -3/ ..mu..g/ml) inhibit both spontaneous and radiation-induced mutagenesis. The effect of high concentrations (10 and 100 ..mu..g/ml) causes a mutagenic effect.

  18. Three new monoterpene glucosides from Senecio solidagineus.

    PubMed

    Li, Dingxiang; Chou, Guixin; Wang, Zhengtao

    2014-07-01

    Three new monoterpene glucosides, solidagin A, B, and C (1-3), together with two known alkaloids, senecionine (4) and senkirkine (5), were isolated from Senecio solidagineus, and their structures were elucidated on the basis of 1D and 2D NMR spectral analysis. PMID:25230485

  19. Stability of Limonin Glucoside in Beverage Matrices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limonin glucoside, a highly oxygenated triterpenoid secondary metabolite found in significant quantities in Citrus and reported to possess multiple health-promoting properties, is being considered for incorporation into beverages as a functional component. In preparation of a multi-week human study...

  20. Bis-iridoid glucosides from Abelia chinensis.

    PubMed

    Tomassini, L; Foddai, S; Serafini, M; Cometa, M F

    2000-07-01

    Seven bis-iridoid glucosides have been isolated from Abelia chinensis and were characterized by having a secoiridoid residue as unit A esterifying a C(10)-iridoid or a delta-lactone iridoid as unit B. Among these, compounds 1-3 are new and correspond to 7-O-acetyllaciniatoside IV, 7-O-acetyllaciniatoside V, and 7-O-acetylabelioside B, respectively. The structures of 1-3 were elucidated by spectral methods. PMID:10924185

  1. Screening for Bacillus subtilis group isolates that degrade cyanogens at pH 4.5-5.0.

    PubMed

    Abban, Stephen; Brimer, Leon; Abdelgadir, Warda S; Jakobsen, Mogens; Thorsen, Line

    2013-01-15

    Cyanogenic food crops abound in nature with important crops like cassava forming the staple food for over half a billion people. Detoxification by hydrolysis of cassava cyanogenic glycosides often involves acid fermentation, and in some of these processes Bacillus species are encountered. Forty Bacillus spp. (20 Bacillus subtilis, 11 Bacillus licheniformis, 7 Bacillus sonorensis, 2 Bacillus cereus) isolated from acid fermented primary starters to produce Gergoush, a Sudanese fermented snack, were screened for their ability to grow and to hydrolyze linamarin, the major cyanogen found in cassava at pH levels below 5.0; also the cyanogen amygdalin was assessed. The B. subtilis isolates grew in both HCl and lactic acid environments from pH 4.5-6.0 while being able to break down the cyanogenic glycosides. The B. licheniformis and B. sonorensis isolates grew and degraded cyanogens at pH 5.0 in a HCl environment, while two B. cereus isolates used in the study showed no breakdown reaction under all conditions tested. One B. subtilis isolate was observed to have substrate specificity between the breakdown of linamarin and amygdalin. We conclude that some Bacillus spp. isolates are important in the microbiological breakdown of cyanogens in cassava fermentations even at pH 4.5-5.0 though further investigations are required. PMID:23261810

  2. A new acylated isoflavone glucoside from Pterocarpus santalinus.

    PubMed

    Krishnaveni, K S; Srinivasa Rao, J V

    2000-09-01

    Phytochemical investigation on the constituents of heartwood of Pterocarpus santalinus resulted in the isolation of a new acylated isoflavone glucoside. The structure of the new compound was elucidated on the basis of spectral studies as 4',5-dihydroxy-7-O-methyl isoflavone 3'-O-D-(3''-E-cinnamoyl)glucoside. PMID:10993243

  3. Mycotoxins and cyanogenic glycosides in staple foods of three indigenous people of the Colombian Amazon.

    PubMed

    Diaz, Gonzalo J; Krska, Rudolf; Sulyok, Michael

    2015-01-01

    A study was conducted to determine the incidence and levels of mycotoxins in the main staple foods of three indigenous people of the Colombian Amazon. A total of 20 corn, 24 rice and 59 cassava samples were analysed by a multi-analyte liquid chromatography-tandem mass spectrometry method covering the major classes of mycotoxins. In addition, cassava samples were also analysed for cyanogenic glycosides. The indigenous Amazon communities tested are exposed to potentially carcinogenic mycotoxins (particularly aflatoxins), as well as other mycotoxins, mainly through the intake of locally grown corn. Citrinin content in this corn was unusually high and has not been reported elsewhere. Two cassava samples contained high levels of cyanogenic glycosides. It is strongly recommended not to grow corn in the Amazon but instead purchase it from vendors capable of guaranteeing mycotoxin levels below the maximum allowable concentration in Colombia. PMID:26391446

  4. Probing non polar interstellar molecules through their protonated form: Detection of protonated cyanogen (NCCNH+)★

    PubMed Central

    Agúndez, M.; Cernicharo, J.; de Vicente, P.; Marcelino, N.; Roueff, E.; Fuente, A.; Gerin, M.; Guélin, M.; Albo, C.; Barcia, A.; Barbas, L.; Bolaño, R.; Colomer, F.; Diez, M. C.; Gallego, J. D.; Gómez-González, J.; López-Fernández, I.; López-Fernández, J. A.; López-Pérez, J. A.; Malo, I.; Serna, J. M.; Tercero, F.

    2015-01-01

    Cyanogen (NCCN) is the simplest member of the series of dicyanopolyynes. It has been hypothesized that this family of molecules can be important constituents of interstellar and circumstellar media, although the lack of a permanent electric dipole moment prevents its detection through radioastronomical techniques. Here we present the first solid evidence of the presence of cyanogen in interstellar clouds through the detection of its protonated form toward the cold dark clouds TMC-1 and L483. Protonated cyanogen (NCCNH+) has been identified through the J = 5 – 4 and J = 10 – 9 rotational transitions using the 40m radiotelescope of Yebes and the IRAM 30m telescope. We derive beam averaged column densities for NCCNH+ of (8.6 ± 4.4) × 1010 cm−2 in TMC-1 and (3.9 ± 1.8) × 1010 cm−2 in L483, which translate to fairly low fractional abundances relative to H2, in the range (1-10) × 10−12. The chemistry of protonated molecules in dark clouds is discussed, and it is found that, in general terms, the abundance ratio between the protonated and non protonated forms of a molecule increases with increasing proton affinity. Our chemical model predicts an abundance ratio NCCNH+/NCCN of ~ 10−4, which implies that the abundance of cyanogen in dark clouds could be as high as (1-10) × 10−8 relative to H2, i.e., comparable to that of other abundant nitriles such as HCN, HNC, and HC3N. PMID:26543239

  5. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Methyl glucoside-coconut oil ester. 172.816... § 172.816 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester may be safely used in food in accordance with the following conditions: (a) It is the methyl glucoside-coconut oil...

  6. Cyanogenic glycosides in plant-based foods available in New Zealand.

    PubMed

    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.  PMID:23984870

  7. Malonyl isoflavone glucosides are chiefly hydrolyzed and absorbed in the colon.

    PubMed

    Yonemoto-Yano, Hiroko; Maebuchi, Motohiro; Fukui, Kensuke; Tsuzaki, Shinichi; Takamatsu, Kiyoharu; Uehara, Mariko

    2014-03-12

    Malonyl isoflavone glucosides are water-soluble derivatives of soybean hypocotyls. This study compared the hydrolysis and absorption of malonyl isoflavone glucosides and nonmalonyl isoflavone glucosides in rats. Plasma concentrations of isoflavones were measured after oral administration of malonyl isoflavone glucosides or isoflavone glucosides. After fasting, the duodenum, jejunum, ileum, and colon were excised, and homogenates were prepared. The extent of hydrolysis of each glucoside by each intestinal homogenate was measured. Plasma levels of isoflavone aglycones, such as daidzein and glycitein, were higher in rats administered malonyl isoflavone glucosides than in those administered isoflavone glucosides. The area under the curve of daidzein in plasma of rats administered malonyl isoflavone glucosides was also significantly greater than that in those administered isoflavone glucosides. A transport experiment using Caco-2 cells suggested that degradation of malonyl glucosides to aglycones is necessary for intestinal absorption. Malonyl isoflavone glucosides were hydrolyzed only in the colon, whereas hydrolysis of isoflavone glucosides occurred in the jejunum, ileum, and colon. These results indicated more effective absorption of malonyl isoflavone glucosides than of nonmalonyl isoflavone glucosides. Moreover, effective absorption of malonyl isoflavone aglycones in the colon contributed to the significant increase in plasma isoflavone levels. PMID:24524651

  8. [Evaluation of an analytical method for cyanogenic compounds in bean paste and its application for surveillance of real samples].

    PubMed

    Tsutsumi, Tomoaki; Ishii, Rika; Matsuda, Rieko

    2013-01-01

    In order to ensure compliance of raw bean paste products with the Japanese Food Sanitation Law, we examined the performance characteristics of an analytic procedure based on steam distillation followed by carbonate-pyrazolone assay to determine cyanogenic compounds in raw bean paste. The present method includes a procedure for decomposition cyanogenic glycosides using linamarase due to the possibility that cyanogenic glycoside-hydrolyzing enzymes might be deactivated in raw bean pastes. The performance of the method was evaluated using two types of bean paste spiked with a cyanogenic glycoside (linamarin) corresponding to cyanide ion concentrations of 5 and 10 mg/kg. The trueness of the method was 86-90%, and the repeatability (RSD) was 1.0-2.4%, while the intermediate precision (RSD) was 2.6% to 4.9%. A surveillance of cyanogenic compounds in 28 raw bean pastes manufactured in Japan was then carried out with the validated method. One sample contained 15 mg/kg (as hydrogen cyanide), while the other samples contained less than 5 mg/kg. PMID:24025215

  9. The Reactions of Methanimine and Cyanogen with Carbon Monoxide in Prebiotic Molecular Evolution on Earth

    NASA Astrophysics Data System (ADS)

    Aylward, Nigel; Bofinger, Neville

    2001-12-01

    A primeval atmosphere is proposed containing simple molecules such as formaldehyde, ammonia, carbon monoxide, cyanogen and hydrogen cyanide, which have been detected in space. Chemical reactions are described for the formation of aziridine-2-one and di-azirine-3-one derivatives as potential precursors for the original synthesesis of amino-acids, proteins, pyrimidines, purines, nicotinamide and flavin. The reactions have been shown to be kinetically feasible from the overall enthalpy changes in the ZKE approximation at the MP2/6-31G^* level.

  10. New iridoid glucosides from the aerial parts of Verbena brasiliensis.

    PubMed

    Ono, Masateru; Oishi, Kanna; Abe, Hiroaki; Masuoka, Chikako; Okawa, Masafumi; Ikeda, Tsuyoshi; Nohara, Toshihiro

    2006-10-01

    Two new iridoid glucosides, verbenabraside A (1) and verbenabraside B (2), were isolated from the aerial parts of Verbena brasiliensis VELL., along with six known iridoid glucosides, gelsemiol 3-O-beta-D-glucoside (3), verbraside (4), 9-hydroxysemperoside (5), griselinoside (6), aralidioside (7), and 6alpha-hydroxyforsythide dimethyl ester (8), three known phenylethanoid glycosides, 2-phenylethyl O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (9), acteoside (10), and leucosceptoside A (11), two known lignan glucosides, dihydroxymethyl-bis(3,5-dimethoxy-4-hydroxyphenyl) tetrahydrofuran-9 (or 9')-O-beta-glucopyranoside (12) and (+)-lyoniresinol 3alpha-O-beta-D-glucopyranoside (13), a known methyl salicylate glucoside, methyl 2-O-beta-D-glucopyranosylbenzoate (14), and two known sterols, beta-sitosterol 3-O-beta-D-glucopyranoside (15) and beta-sitosterol (16). Their chemical structures were determined on the basis of spectroscopic data. Compound 1 exhibited stronger scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl than that of alpha-tocopherol. PMID:17015981

  11. Strategies for elimination of cyanogens from cassava for reducing toxicity and improving food safety.

    PubMed

    Nambisan, Bala

    2011-03-01

    Toxicity of cassava arises due to the presence of the cyanoglucosides linamarin and lotaustralin which are hydrolysed by endogenous enzyme linamarase to acetonecyanohydrin (ACN) and cyanide (CN) which are toxic. Major research efforts to eliminate/reduce cyanoglucosides have focused on (i) development of acyanogenic cassava varieties by breeding; (ii) controlling its metabolism; and (iii) processing to remove cyanogens. The cyanoglucoside (CNG) content in cassava is genetically controlled and cultivars may be classified as low (<50 μg/g), medium (50-100 μg/g) and high CN (>100 μg CN eq./g) varieties. Molecular techniques for reducing tuber CNG have focused on development of transgenic plants with reduced expression of cyt P 450 in leaves, or increased expression of hydroxynitrilelyase in tuber. For immediate solution, CNG content can be reduced using several processing methods. Traditional methods used for processing include boiling, drying, parboiling and drying, baking, steaming, frying and preparation of flour. These processes result in CN losses ranging from 25% to 98%. The cyanogen level in the final product is influenced both by the tuber CNG and the method of processing. In order to achieve safe levels of 10 μg/g in cassava products, new methods of processing, especially for cassava containing more than 250 μg CN eq./g, remains a challenging problem. PMID:21074593

  12. Anticomplement monoterpenoid glucosides from the root bark of Paeonia suffruticosa.

    PubMed

    Song, Wei-Hua; Cheng, Zhi-Hong; Chen, Dao-Feng

    2014-01-24

    Six new (1-6) and 19 known monoterpenoid glucosides were isolated from the root bark of Paeonia suffruticosa. The monoterpenoid glucosides 1, 2, 7, 10-19, and 22 exhibited anticomplement effects with CH50 and AP50 values ranging from 0.14 to 2.67 mM and 0.25 to 3.67 mM, respectively. In a mechanistic study, suffrupaeoniflorin A (1) interacted with C1q, C3, C5, and C9, while galloylpaeoniflorin (12) and galloyloxypaeoniflorin (19) acted on C1q, C3, and C5 components in the complement activation cascade. PMID:24377852

  13. Absorption and excretion of conjugated flavonols, including quercetin-4'-O-beta-glucoside and isorhamnetin-4'-O-beta-glucoside by human volunteers after the consumption of onions.

    PubMed

    Aziz, A A; Edwards, C A; Lean, M E; Crozier, A

    1998-09-01

    Flavonols are polyphenols found ubiquitously in plants and plant-products. Flavonols, particularly quercetin, are potent antioxidants in vitro and their intake has been associated inversely with the incidence of coronary heart disease. The aim of this study was to investigate the accumulation in plasma and excretion in urine of flavonol glucosides following ingestion of lightly fried onions. Five healthy volunteers followed a low-flavonoid diet for 3 days. On day 4, after an overnight fast, subjects were given 300 g of lightly fried yellow onions which contain conjugates of quercetin and isorhamnetin, including quercetin-3,4 '-diO-beta-glucoside, isorhamnetin-4'-O-beta-glucoside and quercetin-4'-O-beta-glucoside. Blood collection was carried out at 0 min, 0.5, 1.0, 1.5, 2, 3, 4, 5 and 24h after the supplement. In addition, subjects collected all their urine for 24h following the onion supplement. Isorhamnetin-4'-O-beta-glucoside and quercetin-4 '-O-beta-glucoside accumulated in plasma with maximum levels, defined as proportion of intake, of 10.7+/-2.6% and 0.13+/-0.03% respectively. The time of the quercetin-4'glucoside peak plasma concentration was 1.3+/-0.2 h after the ingestion of onions while a value of 1.8+/-0.7 h was obtained for isorhamnetin-4'-glucoside. Excretion in urine, as a proportion of intake, was 17.4+/-8.3% for isorhamnetin-4'-O-beta-glucoside and 0.2+/-0.1% for quercetin-4'-O-beta-glucoside. Possible reasons for the accumulation and excretion of isorhamnetin-4'-glucoside in proportionally much higher amounts than quercetin-4'-glucoside are discussed. It is concluded that flavonols are absorbed into the bloodstream as glucosides and minor structural differences affect markedly both the level of accumulation and the extent to which the conjugates are excreted. PMID:9802557

  14. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl glucoside-coconut oil ester. 178.3600... SANITIZERS Certain Adjuvants and Production Aids § 178.3600 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester identified in § 172.816(a) of this chapter may be safely used as a...

  15. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut...

  16. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl glucoside-coconut oil ester. 172.816 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.816 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester may be safely used in food in accordance with the following conditions: (a) It is...

  17. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Methyl glucoside-coconut oil ester. 178.3600... SANITIZERS Certain Adjuvants and Production Aids § 178.3600 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester identified in § 172.816(a) of this chapter may be safely used as a...

  18. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Methyl glucoside-coconut oil ester. 178.3600 Section 178.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Production Aids § 178.3600 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester...

  19. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Methyl glucoside-coconut oil ester. 172.816... HUMAN CONSUMPTION Multipurpose Additives § 172.816 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester may be safely used in food in accordance with the following conditions: (a) It is...

  20. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut...

  1. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut...

  2. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Methyl glucoside-coconut oil ester. 172.816... HUMAN CONSUMPTION Multipurpose Additives § 172.816 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester may be safely used in food in accordance with the following conditions: (a) It is...

  3. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut...

  4. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Methyl glucoside-coconut oil ester. 178.3600... SANITIZERS Certain Adjuvants and Production Aids § 178.3600 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester identified in § 172.816(a) of this chapter may be safely used as a...

  5. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut...

  6. Enzymatic Synthesis of Acylphloroglucinol 3-C-Glucosides from 2-O-Glucosides using a C-Glycosyltransferase from Mangifera indica.

    PubMed

    Chen, Dawei; Sun, Lili; Chen, Ridao; Xie, Kebo; Yang, Lin; Dai, Jungui

    2016-04-18

    A green and cost-effective process for the convenient synthesis of acylphloroglucinol 3-C-glucosides from 2-O-glucosides was exploited using a novel C-glycosyltransferase (MiCGTb) from Mangifera indica. Compared with previously characterized CGTs, MiCGTb exhibited unique de-O-glucosylation promiscuity and high regioselectivity toward structurally diverse 2-O-glucosides of acylphloroglucinol and achieved high yields of C-glucosides even with a catalytic amount of uridine 5'-diphosphate (UDP). These findings demonstrate for the first time the significant potential of a single-enzyme approach to the synthesis of bioactive C-glucosides from both natural and unnatural acylphloroglucinol 2-O-glucosides. PMID:26918309

  7. Selective detection of toxic cyanogen gas in the presence of O2, and H2O molecules using a AlN nanocluster

    NASA Astrophysics Data System (ADS)

    Solimannejad, Mohammad; Kamalinahad, Saeedeh; Shakerzadeh, Ehsan

    2016-08-01

    The interaction of cyanogen molecule with Al12N12 nanocage has been studied using density functional theory (DFT) at CAM-B3LYP/6-31+G(d) level. Geometric, electronic structure and natural bond orbitals (NBO) analysis display that adsorption of cyanogen onto exterior surface of Al12N12 is physisorption with adsorption energy (Eads) equal to -55.36 kJ/mol. UV-vis study shows a high intensity peak in 388.9 nm due to interaction of gas with nanocage. It is expected that Al12N12 will be used in designing novel materials for potential applications to detect toxic cyanogen molecule.

  8. Anti-allergic inflammatory effects of cyanogenic and phenolic glycosides from the seed of Prunus persica.

    PubMed

    Kim, Geum Jin; Choi, Hyun Gyu; Kim, Ji Hyang; Kim, Sang Hyun; Kim, Jeong Ah; Lee, Seung Ho

    2013-12-01

    A methanol extract of the seed of Prunus persica (Rosaceae) was found to inhibit histamine release in human mast cells. Activity-guided fractionation of the methanol extract yielded three cyanogenic glycosides (1-3) and other phenolic compounds (4-8). To evaluate their anti-allergic and anti-inflammatory activities, the isolates (1-8) were tested for their inhibitory effects on histamine release and on the gene expressions of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 in human mast cells. Of these, phenolic glycosides 7 and 8 suppressed histamine release and inhibited the pro-inflammatory cytokines TNF-alpha and IL-6. These results suggest that isolates from P. persica are among the anti-allergic inflammatory principles in this medicinal plant. PMID:24555287

  9. Characterization of the major cyanogen bromide fragment of alpha-A crystallin

    NASA Technical Reports Server (NTRS)

    Ifeanyi, F.; Takemoto, L.; Spooner, B. S. (Principal Investigator)

    1991-01-01

    Alpha crystallin from the bovine lens has been digested with cyanogen bromide, and the major fragment (CB-1) has been purified using reverse phase HPLC. Characterization of this fragment by Edman degradation and antisera to synthetic peptides indicates that it originates from alpha-A crystallin, but lacks the N-terminal methionine and the last 35 amino acids from the C-terminus of the molecule. The purified CB-1 fragment binds as well as native alpha crystallin to lens membrane, but is unable to self-assemble into the correct size of high molecular weight oligomeric complexes characteristic of the intact alpha-A chain. Together, these results demonstrate that the alpha-A chain is comprised of at least two functional domains, one of which is involved in binding of alpha-A crystallin to lens membrane, and another which is necessary for correct self-assembly of the molecule into high molecular weight oligomers.

  10. Konzo: From Poverty, Cassava, and Cyanogen Intake to Toxico-Nutritional Neurological Disease

    PubMed Central

    Nzwalo, Hipólito; Cliff, Julie

    2011-01-01

    Konzo is a distinct neurological entity with selective upper motor neuron damage, characterized by an abrupt onset of an irreversible, non-progressive, and symmetrical spastic para/tetraparesis. Despite its severity, konzo remains a neglected disease. The disease is associated with high dietary cyanogen consumption from insufficiently processed roots of bitter cassava combined with a protein-deficient diet. Epidemics occur when these conditions coincide at times of severe food shortage. Up to 1993, outbreaks in poor rural areas in Africa contributed to more than 3,700 cases of konzo. The number of affected people is underestimated. From unofficial reports, the number of cases was estimated to be at least 100,000 in 2000, in contrast to the 6,788 cases reported up to 2009 from published papers. PMID:21738800

  11. The Case of the Missing Cyanogen-rich AGB Stars in Galactic Globular Clusters

    NASA Astrophysics Data System (ADS)

    Campbell, S. W.; Yong, D.; Wylie-de Boer, E. C.; Stancliffe, R. J.; Lattanzio, J. C.; Angelou, G. C.; Grundahl, F.; Sneden, C.

    2012-08-01

    The handful of available observations of AGB stars in Galactic Globular Clusters suggest that the GC AGB populations are dominated by cyanogen-weak stars (eg. Norris et al. 1981; Sneden et al. 2000). This contrasts strongly with the distributions on the RGB (and other) populations, which generally show a 50:50 bimodality in CN band strength. If this is a real difference then it presents a serious problem for low metallicity stellar evolution theory - since such a surface abundance change going from the RGB to AGB is not predicted by stellar models. However this is only a tentative conclusion, since it is based on very small AGB sample sizes. To test whether this problem really exists we have carried out an observational campaign targeting AGB stars in GCs. Our preliminary results indicate there is indeed a lack of CN-strong AGB stars.

  12. Recent Developments of C-Aryl Glucoside SGLT2 Inhibitors.

    PubMed

    Zhang, Yang; Liu, Zhao-Peng

    2016-01-01

    Sodium-glucose cotransporter 2 (SGLT2) is almost exclusively expressed in the proximal renal tubules. It is responsible for about 90% of the glucose reabsorption from tubular fluid. Selective inhibition of SGLT2 is expected to favor in the normalization of plasma glucose levels in T2DM patients through the prevention of renal glucose reabsorption and the promotion of glucose excretion from urine. Selective SGLT2 inhibitors have the merits to minimize the gastrointestinal side effects associated with SGLT1 inhibition, and selective SGLT2 inhibition may have a low risk of hypoglycemia. Since the C-aryl glucosides are metabolically more stable than the O-glucosides, numerous efforts have been made in the development of potent and selective C-aryl glucoside SGLT2 inhibitors, and a number of them are now used as anti-diabetes drugs in clinic or at various stages of clinical developments. Based on their structural features, in this review, these SGLT2 inhibitors are classified as three types: the phenyl/arylmethylphenyl C-glucosides, with an emphasis on the modifications on the proximal and/or the distal phenyl ring, and the spacer; the heteroarylmethylphenyl Cglucosides, with a replacement of the distal phenyl ring by a heterocycle like pyridazine, pyrimidine, thiophene and benzothiophene, thiazole, 1,3,4-thiadiazole, and triazolopyridinone; and the glucose-modified Caryl glucosides, including the glucose C-1 derived O-spiroketals, C-4 gem-difluoro analogues, C-5 and C-6 modified derivatives, dioxa-bicyclo[3.2.1]octane bridged ketals, the thioglucosides, and carbasugars. The structure-activity relationships (SARs) of each type along with their inhibitory potency against human SGLT2 and selectivity over human SGLT1 are discussed. PMID:26861002

  13. Purity analysis of hydrogen cyanide, cyanogen chloride and phosgene by quantitative (13)C NMR spectroscopy.

    PubMed

    Henderson, Terry J; Cullinan, David B

    2007-11-01

    Hydrogen cyanide, cyanogen chloride and phosgene are produced in tremendously large quantities today by the chemical industry. The compounds are also particularly attractive to foreign states and terrorists seeking an inexpensive mass-destruction capability. Along with contemporary warfare agents, therefore, the US Army evaluates protective equipment used by warfighters and domestic emergency responders against the compounds, and requires their certification at > or = 95 carbon atom % before use. We have investigated the (13)C spin-lattice relaxation behavior of the compounds to develop a quantitative NMR method for characterizing chemical lots supplied to the Army. Behavior was assessed at 75 and 126 MHz for temperatures between 5 and 15 degrees C to hold the compounds in their liquid states, dramatically improving detection sensitivity. T(1) values for cyanogen chloride and phosgene were somewhat comparable, ranging between 20 and 31 s. Hydrogen cyanide values were significantly shorter at 10-18 s, most likely because of a (1)H--(13)C dipolar contribution to relaxation not possible for the other compounds. The T(1) measurements were used to derive relaxation delays for collecting the quantitative (13)C data sets. At 126 MHz, only a single data acquisition with a cryogenic probehead gave a signal-to-noise ratio exceeding that necessary for certifying the compounds at > or = 95 carbon atom % and 99% confidence. Data acquired at 75 MHz with a conventional probehead, however, required > or = 5 acquisitions to reach this certifying signal-to-noise ratio for phosgene, and >/= 12 acquisitions were required for the other compounds under these same conditions. In terms of accuracy and execution time, the NMR method rivals typical chromatographic methods. PMID:17924355

  14. One New Conjugate of a Secoiridoid Glucoside with a Sesquiterpene Glucoside from the Flower Buds of Lonicera japonica.

    PubMed

    Yang, Biao; Meng, Zhaoqing; Ma, Yimin; Wang, Zhenzhong; Ding, Gang; Huang, Wenzhe; Sun, Lin; Hu, Yumei; Liu, Wenjun; Zhang, Chunxiao; Cao, Zeyu; Li, Jiachun; Zhong, Yan; Xiao, Wei

    2015-09-01

    Secosesquside (1), a new secoiridoid glucoside-sesquiterpene conjugate, together with three known secoiridoid derivatives, were isolated from flower buds of Lonicerajaponica. The isolated compounds were elucidated by extensive spectroscopic analyses, especially 2D NMR experiments. The anti-inflammatory activities of the new compound were also evaluated by enzyme-linked immunosorbent assay. PMID:26594743

  15. Comparison of the Use of Gas Chromotography, Spectrophotometry, and Near Infrared Spectropscopy to Quantify Prussic Acid Potential in Forages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sorghum [Sorghum bicolor (L.) Moench] has been shown to contain the cyanogenic glycoside dhurrin, which is responsible for the disorder known as prussic acid poisoning in livestock. The current standard method for estimating HCN uses spectrophotometery to measure the aglycone of the dhurrin, p-hydro...

  16. Differential effects on the cyanogenic glycoside content of fermenting cassava root pulp by beta-glucosidase and microbial activities.

    PubMed

    Maduagwu, E N

    1983-03-01

    The degradation of cyanogenic glycosides was studied in spontaneously fermenting cassava root pulp and in fresh pulp samples pretreated to prevent either endogenous beta-glycosidase activity, fermentation, or both. The rate of disappearance of the glycosides, as measured by hydrocyanic acid (HCN) production in situ, in membrane-sterilised media or in samples containing 1% sodium iodoacetate, was comparable with the untreated control in which 85% of the substrate was broken down within 72 h. Pretreatment of the fresh pulp with the beta-glucosidase inhibitor 1,5-gluconolactone (1%) markedly reduced the rate of disappearance of the cyanogens while inclusion of glucose in this test medium at the 3% level appeared to induce some hydrolysis. Loss of bound (glycosidic) cyanide in sterilised medium containing the glucosidase inhibitor was negligible. The results suggest that the contribution of the fermentation process in cyanide detoxification of pulped cassava roots is minimal. PMID:6404010

  17. Iridoid glucosides in the endemic Picconia azorica (Oleaceae).

    PubMed

    Gousiadou, Chrysoula; Kokubun, Tetsuo; Martins, José; Gotfredsen, Charlotte H; Jensen, Søren R

    2015-07-01

    In our continued investigation of plants from the family Oleaceae we have now investigated Picconia azorica endemic to the Azores. Like most species within the family it contains the oleoside-based secoiridoid glucosides ligstroside and oleuropein as the main compounds and in addition verbascoside and echinacoside. As with the previously investigated Picconia excelsa, it also contained the carbocyclic iridoid glucosides involved in the biosynthetic pathway to the oleoside derivatives. However, while P. excelsa contained loganin esterified with some monoterpenoid acids, P. azorica contains similar esters of 7-epi-loganic acid named Picconioside A and B. In addition were found the two 7-O-E/Z-cinnamoyl esters of 7-epi-loganic acid named Picconioside C and D. PMID:25687603

  18. Enzymatic Biosynthesis of Novel Resveratrol Glucoside and Glycoside Derivatives.

    PubMed

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

    2014-12-01

    A UDP glucosyltransferase from Bacillus licheniformis was overexpressed, purified, and incubated with nucleotide diphosphate (NDP) d- and l-sugars to produce glucose, galactose, 2-deoxyglucose, viosamine, rhamnose, and fucose sugar-conjugated resveratrol glycosides. Significantly higher (90%) bioconversion of resveratrol was achieved with α-d-glucose as the sugar donor to produce four different glucosides of resveratrol: resveratrol 3-O-β-d-glucoside, resveratrol 4'-O-β-d-glucoside, resveratrol 3,5-O-β-d-diglucoside, and resveratrol 3,5,4'-O-β-d-triglucoside. The conversion rates and numbers of products formed were found to vary with the other NDP sugar donors. Resveratrol 3-O-β-d-2-deoxyglucoside and resveratrol 3,5-O-β-d-di-2-deoxyglucoside were found to be produced using TDP-2-deoxyglucose as a donor; however, the monoglycosides resveratrol 4'-O-β-d-galactoside, resveratrol 4'-O-β-d-viosaminoside, resveratrol 3-O-β-l-rhamnoside, and resveratrol 3-O-β-l-fucoside were produced from the respective sugar donors. Altogether, 10 diverse glycoside derivatives of the medically important resveratrol were generated, demonstrating the capacity of YjiC to produce structurally diverse resveratrol glycosides. PMID:25239890

  19. The glucosidic pathways and glucose production by frog muscle.

    PubMed

    Fournier, P A; Petrof, E O; Guderley, H

    1992-04-25

    Resting muscle is generally perceived as a glucose-utilizing organ; however, we show that resting well-oxygenated frog muscle recovering from strenuous exercise can release significant amounts of glucose. The metabolic pathway responsible for this process does not involve glucose-6-phosphatase because this enzyme is undetectable in frog muscle. The participation of amylo-1,6-glucosidase in the production of glucose is also ruled out since neither marked net phosphorolytic breakdown of glycogen nor considerable cycling between glycogen and glucose 6-phosphate occur. The glucosidic pathways of glycogen breakdown are the likely source of glucose as they are the only metabolic avenues with sufficient capacity to account for the rate at which glucose is released from post-exercised muscle. This rate of glucose production is high enough to be of physiological importance. Our results clearly indicate that to measure lactate glycogenesis in muscle, the simultaneous hydrolysis of muscle glycogen by the glucosidic pathways must be taken into account to prevent marked underestimation of the rate of glycogen synthesis. The glucosidic pathways seem the predominant avenues of glycogen breakdown in post-exercised resting frog muscle and are active enough to account for the rate of glycogen breakdown in resting muscle, suggesting that these rather than the phosphorolytic pathways are the chief routes of glycogen breakdown in resting muscle. PMID:1569076

  20. Binding and relaxometric properties of heme complexes with cyanogen bromide fragments of human serum albumin.

    PubMed Central

    Monzani, Enrico; Curto, Maria; Galliano, Monica; Minchiotti, Lorenzo; Aime, Silvio; Baroni, Simona; Fasano, Mauro; Amoresano, Angela; Salzano, Anna Maria; Pucci, Piero; Casella, Luigi

    2002-01-01

    The spectroscopic and reactivity properties of hemin complexes formed with cyanogen bromide fragments B (residues 1-123), C (124-298), A (299-585), and D (1-298) of human serum albumin (HSA) have been investigated. The complex hemin-D exhibits binding, spectral, circular dichroism, and reactivity characteristics very similar to those of hemin-HSA, indicating that fragment D contains the entire HSA domain involved in heme binding. The characteristics of the other hemin complexes are different, and a detailed investigation of the properties of hemin-C has been carried out because this fragment contains the HSA binding region of several important drugs. Hemin-C contains a low-spin Fe(III) center, with two imidazole ligands, but the complex undergoes a reversible structural transition at basic pH leading to a high-spin, five-coordinated Fe(III) species. This change determines a marked increase in the relaxation rate of water protons. Limited proteolysis experiments and mass spectral analysis carried out on fragment C and hemin-C show that the region encompassing residues Glu-208 to Trp-214 is protected from activity of proteases in the complex and, therefore, is involved in the interaction with hemin. A structural model of fragment C enables us to propose that His-242 and His-288 are the axial ligands for the Fe(III) center. PMID:12324442

  1. Straightforward rapid spectrophotometric quantification of total cyanogenic glycosides in fresh and processed cassava products.

    PubMed

    Tivana, Lucas Daniel; Da Cruz Francisco, Jose; Zelder, Felix; Bergenståhl, Bjorn; Dejmek, Petr

    2014-09-01

    In this study, we extend pioneering studies and demonstrate straightforward applicability of the corrin-based chemosensor, aquacyanocobyrinic acid (ACCA), for the instantaneous detection and rapid quantification of endogenous cyanide in fresh and processed cassava roots. Hydrolytically liberated endogenous cyanide from cyanogenic glycosides (CNp) reacts with ACCA to form dicyanocobyrinic acid (DCCA), accompanied by a change of colour from orange to violet. The method was successfully tested on various cassava samples containing between 6 and 200 mg equiv. HCN/kg as verified with isonicotinate/1,3-dimethylbarbiturate as an independent method. The affinity of ACCA sensor to cyanide is high, coordination occurs fast and the colorimetric response can therefore be instantaneously monitored with spectrophotometric methods. Direct applications of the sensor without need of extensive and laborious extraction processes are demonstrated in water-extracted samples, in acid-extracted samples, and directly on juice drops. ACCA showed high precision with a standard deviation (STDV) between 0.03 and 0.06 and high accuracy (93-96%). Overall, the ACCA procedure is straightforward, safe and easily performed. In a proof-of-concept study, rapid screening of ten samples within 20 min has been tested. PMID:24731309

  2. Antibiotic-modifying activity of riachin, a non-cyanogenic cyanoglycoside extracted from Bauhinia pentandra

    PubMed Central

    de Farias, Pablo Antonio Maia; Figueredo, Fernando Gomes; Lucas, Aline Maria Brito; de Moura, Rafael Barbosa; Coutinho, Henrique Douglas Melo; da Silva, Tania Maria Sarmento; Martin, Ana Luiza de Aguiar Rocha; Fonteles, Marta Maria de França

    2015-01-01

    Background The search for new active compounds from the Brazilian flora has intensified in recent years, especially for new drugs with antibiotic potential. Accordingly, the aim of this study was to determine whether riachin has antibiotic activity in itself or is able to modulate the activity of conventional antibiotics. Methods A non-cyanogenic cyanoglycoside known as riachin was isolated from Bauhinia pentandra, and was tested alone and in combination with three antibiotics (clindamycin, amikacin, and gentamicin) against multiresistant bacterial strains (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus). Results Riachin did not show significant antibiotic activity when tested alone against any strain (P>0.05). However, when combined with conventional antibiotics, it showed drug-modifying activity against strains of S. aureus exposed to clindamycin (P<0.001) as well as against P. aeruginosa exposed to amikacin (P<0.001). Although riachin did not show direct antibiotic activity, it had synergistic activity when combined with amikacin or clindamycin. The mechanism of action of this synergism is under investigation. Conclusion The results of this work demonstrate that some substances of natural origin can enhance the effectiveness of certain antibiotics, which means a substantial reduction in the drug dose required and possibly in consequent adverse events for patients. PMID:26109849

  3. An efficient fermentation method for the degradation of cyanogenic glycosides in flaxseed.

    PubMed

    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. PMID:22530603

  4. Cyanogen in NGC 1851 Red Giant Branch and Asymptotic Giant Branch Stars: Quadrimodal Distributions

    NASA Astrophysics Data System (ADS)

    Campbell, S. W.; Yong, D.; Wylie-de Boer, E. C.; Stancliffe, R. J.; Lattanzio, J. C.; Angelou, G. C.; D'Orazi, V.; Martell, S. L.; Grundahl, F.; Sneden, C.

    2012-12-01

    The Galactic globular cluster NGC 1851 has raised much interest since Hubble Space Telescope photometry revealed that it hosts a double subgiant branch. Here we report on our homogeneous study into the cyanogen (CN) band strengths in the red giant branch (RGB) population (17 stars) and asymptotic giant branch (AGB) population (21 stars) using AAOmega/2dF spectra with R ~ 3000. We discover that NGC 1851 hosts a quadrimodal distribution of CN band strengths in its RGB and AGB populations. This result supports the merger formation scenario proposed for this cluster, such that the CN quadrimodality could be explained by the superposition of two "normal" bimodal populations. A small sample overlap with an abundance catalog allowed us to tentatively explore the relationship between our CN populations and a range of elemental abundances. We found a striking correlation between CN and [O/Na]. We also found that the four CN peaks may be paired—the two CN-weaker populations being associated with low Ba and the two CN-stronger populations with high Ba. If true, then s-process abundances would be a good diagnostic for disentangling the two original clusters in the merger scenario. More observations are needed to confirm the quadrimodality and also the relationship between the subpopulations. We also report CN results for NGC 288 as a comparison. Our relatively large samples of AGB stars show that both clusters have a bias toward CN-weak AGB populations.

  5. CYANOGEN IN NGC 1851 RED GIANT BRANCH AND ASYMPTOTIC GIANT BRANCH STARS: QUADRIMODAL DISTRIBUTIONS

    SciTech Connect

    Campbell, S. W.; Stancliffe, R. J.; Lattanzio, J. C.; Angelou, G. C.; D'Orazi, V.; Yong, D.; Wylie-de Boer, E. C.; Martell, S. L.; Grundahl, F.; Sneden, C. E-mail: david.yong@anu.edu.au

    2012-12-10

    The Galactic globular cluster NGC 1851 has raised much interest since Hubble Space Telescope photometry revealed that it hosts a double subgiant branch. Here we report on our homogeneous study into the cyanogen (CN) band strengths in the red giant branch (RGB) population (17 stars) and asymptotic giant branch (AGB) population (21 stars) using AAOmega/2dF spectra with R {approx} 3000. We discover that NGC 1851 hosts a quadrimodal distribution of CN band strengths in its RGB and AGB populations. This result supports the merger formation scenario proposed for this cluster, such that the CN quadrimodality could be explained by the superposition of two 'normal' bimodal populations. A small sample overlap with an abundance catalog allowed us to tentatively explore the relationship between our CN populations and a range of elemental abundances. We found a striking correlation between CN and [O/Na]. We also found that the four CN peaks may be paired-the two CN-weaker populations being associated with low Ba and the two CN-stronger populations with high Ba. If true, then s-process abundances would be a good diagnostic for disentangling the two original clusters in the merger scenario. More observations are needed to confirm the quadrimodality and also the relationship between the subpopulations. We also report CN results for NGC 288 as a comparison. Our relatively large samples of AGB stars show that both clusters have a bias toward CN-weak AGB populations.

  6. Cassava cyanogens and konzo, an upper motoneuron disease found in Africa.

    PubMed

    Tylleskär, T; Banea, M; Bikangi, N; Cooke, R D; Poulter, N H; Rosling, H

    1992-01-25

    Konzo is a distinct form of tropical myelopathy characterised by abrupt onset of spastic paraparesis. Epidemics in East Africa have been attributed to dietary cyanide exposure from insufficiently processed cassava but a study done in Zaire disputed such an aetiology. We investigated a konzo-affected population in rural Zaire and measured the cyanogen content of cassava flour, determined urinary thiocyanate as an indicator of cyanide intake, and compared blood cyanide concentrations in cases and controls. The affected population consumed flour made from short-soaked (one day) cassava roots and thus had high dietary cyanide exposure (urinary thiocyanate in 31 children = 757 mumol/l) compared with the unaffected population (urinary thiocyanate in 46 children = 50 mumol/l) that ate cassava that had been soaked for three days before consumption. 3 konzo patients, but only 2 of 23 controls, had blood cyanide concentrations above 4 mumol/l (p less than 0.01), although serum thiocyanate concentrations were similar. Our findings indicate a causal role in konzo of sustained high blood cyanide concentrations maintained by a deficient sulphur intake impairing cyanide to thiocyanate conversion. The underlying causes of konzo are poverty and food shortage, but a minor improvement of food processing may, as in beri-beri, be preventive. PMID:1346173

  7. Acute toxicity of some synthetic cyanogens in rats: time-dependent cyanide generation and cytochrome oxidase inhibition in soft tissues after sub-lethal oral intoxication.

    PubMed

    Rao, Pooja; Singh, Poonam; Yadav, Shiv Kumar; Gujar, Niranjan L; Bhattacharya, Rahul

    2013-09-01

    Cyanogens include complex nitrile-containing compounds that can generate free cyanide of toxicological significance. Acute toxicity, time-dependent cyanide generation and cytochrome oxidase (CYTOX) inhibition in soft tissues, and urinary thiocyanate levels were measured after acute cyanogen intoxication in rats. Order of cyanogens in terms of LD₅₀ was: malononitrile (MCN)>propionitrile (PCN)≈sodium nitroprusside (SNP)>acrylonitrile (ACN)>succinonitrile (SCN)>acetonitrile (ATCN) for oral, and SNP>MCN>ACN>PCN>SCN>ATCN for intraperitoneal and subcutaneous routes. MCN was most toxic by oral (LD₅₀=66.4 mg/kg) and SNP by intraperitoneal (LD₅₀=16.7 mg/kg) and subcutaneous (LD₅₀=11.9 mg/kg) routes. Minimum survival time (25 min) was recorded after 4.0 LD₅₀ ATCN. Order of cyanogens (0.75 LD₅₀; oral) on the basis of maximum blood cyanide and time of peak cyanide generation were: ATCN>SNP>SCN>PCN>MCN>ACN, and MCN (30 min)cyanogens, suitable therapeutic windows can be designed for their management. PMID:23831730

  8. A new 5-alkylresorcinol glucoside derivative from Cybianthus magnus.

    PubMed

    Cabanillas, B; Vásquez-Ocmín, P; Zebiri, I; Rengifo, E; Sauvain, M; Le, H L; Vaisberg, A; Voutquenne-Nazabadioko, L; Haddad, M

    2016-01-01

    One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds (2-13), isolated from four plants belonging to Myrsinaceae family. Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. Among the tested molecules, only compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all cell lines tested. One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (2, 3 isolated from C. magnus; 4-7, 10 and 11 isolated from Myrsine latifolia; 4, 8 and 9 isolated from Myrsine sessiflora; 6, 7, 10, 12 and 13 isolated from Myrsine congesta). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of Grevillea robusta. Since resorcinols are known to exhibit strong cytotoxic activity, compounds 1 and 2 were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity in vitro and compounds 3-13 were tested for their antileishmanial activity. Compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all tested cell lines. Compounds 3-13 were not active against Leishmania amazonensis amastigotes. PMID:26181307

  9. Iridoid glucosides from leaves and stem barks of Parkia javanica.

    PubMed

    Dinda, Biswanath; Chandra Mohanta, Bikas; Debnath, Sudhan; Ghosh, Biplab; Arima, Shiho; Sato, Noriko; Harigaya, Yoshihiro

    2009-01-01

    Two new iridoid glucosides, javanicosides A (1) and B (2) along with the known compounds, ursolic acid and beta-sitosterol were isolated from the leaf and stem bark of Parkia javanica and the structures were established on the basis of detailed spectroscopic analysis (MS, 1D, and 2D NMR experiments). The new compounds were identified as 8-O-p-hydroxybenzoyl-6'-O-p-coumaroyl-mussaenosidic acid (1) and 7-O-E-3,4-dimethoxycinnamoyl-6'-O-beta-D-glucopyranosylloganic acid (2). PMID:19408146

  10. An Iridoid Glucoside and the Related Aglycones from Cornus florida

    PubMed Central

    2015-01-01

    A new iridoid glucoside, cornusoside A (1), and four new natural product iridoid aglycones, cornolactones A–D (2–5), together with 10 known compounds were isolated from the leaves of Cornus florida. The structures of compounds 1–5 were established by interpretation of their spectroscopic data. Cornolactone B (3) is the first natural cis-fused tricyclic dilactone iridoid containing both a five- and a six-membered lactone ring. A biosynthesis pathway is proposed for cornolactones C (4) and D (5), the C-6 epimers of compounds 1–3. PMID:25141901

  11. Guaiane-type sesquiterpenoid glucosides from Gardenia jasminoides Ellis.

    PubMed

    Yu, Yang; Gao, Hao; Dai, Yi; Xiao, Gao-Keng; Zhu, Hua-Jie; Yao, Xin-Sheng

    2011-05-01

    Two new guaiane-type sesquiterpenoid glucosides (1 and 2) were isolated from the fruit of Gardenia jasminoides Ellis. Their structures were elucidated to be (1R,7R,10S)-11-O-β-D-glucopyranosyl-4-guaien-3-one (1) and (1R,7R,10S)-7-hydroxy-11-O-β-D-glucopyranosyl-4-guaien-3-one (2) by one- and two-dimensional NMR techniques ((1)H NMR, (13)C NMR, HSQC, HMBC and NOESY), MS, CD spectrometry and chemical methods. PMID:21491483

  12. The protein encoded by the rolB plant oncogene hydrolyses indole glucosides.

    PubMed Central

    Estruch, J J; Schell, J; Spena, A

    1991-01-01

    The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase able to hydrolyse indole-beta-glucosides. Indeed, we show that extracts of bacteria and/or plant tissue expressing the rolB protein hydrolyse indoxyl-beta-glucoside (plant indican). Because of the structural similarity between indoxyl-beta-glucoside and indole-3-acetyl-beta-glucoside (IAA-beta-glucoside), we propose that the physiological and developmental alterations in transgenic plants expressing the rolB gene could be the result of an increased intracellular auxin activity caused by the release of active auxins from inactive beta-glucosides. Thus two of the oncogenes carried by the T-DNA of the plant pathogen Agrobacterium rhizogenes (rolB and rolC) perturb plant growth and development by coding for beta-glucosidases with distinct specificities. Whereas the rolC beta-glucosidase releases cytokinins from their glucoside conjugates, the rolB encoded protein hydrolyses indole-beta-glucosides. The combined action of these two genes therefore is expected to modulate the intracellular concentration of two of the main growth factors active in plants. Images PMID:1915286

  13. Colorimetric Method for the Estimation of Total Limonoid Aglycones and Glucoside Contents in Citrus Juices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method for estimating the total limonoid aglycone and glucoside concentrations in Citrus samples in terms of limonin and limonin glucoside equivalents is presented. The method consists of extraction followed by colorimetric quantification. The colorimetric quantification was based on the formatio...

  14. Anomericity of T-2 Toxin-glucoside: Masked Mycotoxin in Cereal Crops

    PubMed Central

    2015-01-01

    T-2 toxin is a trichothecene mycotoxin produced when Fusarium fungi infect grains, especially oats and wheat. Ingestion of T-2 toxin contaminated grain can cause diarrhea, hemorrhaging, and feed refusal in livestock. Cereal crops infected with mycotoxin-producing fungi form toxin glycosides, sometimes called masked mycotoxins, which are a potential food safety concern because they are not detectable by standard approaches and may be converted back to the parent toxin during digestion or food processing. The work reported here addresses four aspects of T-2 toxin-glucosides: phytotoxicity, stability after ingestion, antibody detection, and the anomericity of the naturally occurring T-2 toxin-glucoside found in cereal plants. T-2 toxin-β-glucoside was chemically synthesized and compared to T-2 toxin-α-glucoside prepared with Blastobotrys muscicola cultures and the T-2 toxin-glucoside found in naturally contaminated oats and wheat. The anomeric forms were separated chromatographically and differ in both NMR and mass spectrometry. Both anomers were significantly degraded to T-2 toxin and HT-2 toxin under conditions that mimic human digestion, but with different kinetics and metabolic end products. The naturally occurring T-2 toxin-glucoside from plants was found to be identical to T-2 toxin-α-glucoside prepared with B. muscicola. An antibody test for the detection of T-2 toxin was not effective for the detection of T-2 toxin-α-glucoside. This anomer was produced in sufficient quantity to assess its animal toxicity. PMID:25520274

  15. Citrus limonin glucoside supplementation decreased biomarkers of liver disease in overweight human subjects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Orange juice and mixtures of citrus limonoid glucosides isolated from orange juice or its byproducts demonstrated health benefits in human and animal studies. However, the risks and benefits of purified limonin glucoside (LG) in humans are unknown. Aim of this study was to determine the safety and m...

  16. Ultraviolet-induced effects on chloramine and cyanogen chloride formation from chlorination of amino acids.

    PubMed

    Weng, ShihChi; Blatchley, Ernest R

    2013-05-01

    Ultraviolet (UV)-based treatment is commonly used to augment chlorination in swimming pools. However, the effects of combined application of UV254/chlorine on disinfection byproduct (DBP) formation are incompletely defined. To examine this issue, experiments were conducted with amino acids (l-arginine, l-histidine, and glycine) that are representative of those introduced to swimming pools via human body fluids. For each precursor, stepwise experiments were conducted with chlorination and UV254 exposure, with/without post-chlorination. Net formation and decomposition of chloramines and cyanogen chloride (CNCl) were measured for a range of chlorine/precursor (Cl/P) molar ratios and UV254 doses. Substantial production of NH2Cl from l-arginine and l-histidine was observed at Cl/P = 1.0 and 2.0 when post-chlorination was applied to UV254-irradiated samples. These results suggested a mechanism of rapid N-chlorination, followed by cleavage of NH3 by UV254 irradiation. CNCl formation was observed from UV254-irradiated samples of l-arginine and l-histidine when Cl/P = 2.0 and 3.0, as well as from glycine for Cl/P ≤ 1. Structurally related precursor compounds were examined for CNCl formation potential in chlorination/UV experiments. CNCl formation was promoted by UV254 exposure of chlorinated imidazole and guanidine compounds, which suggested that these groups contributed to CNCl formation. The results have implications with respect to the application of chlorine and UV for water treatment in swimming pools and other settings, such as water reuse and advanced oxidation processes. PMID:23560482

  17. Determinants of cognitive performance in children relying on cyanogenic cassava as staple food

    PubMed Central

    Bumoko, G. M.; Sombo, M.T.; Okitundu, L.D.; Mumba, D. N.; Kazadi, K. T.; Tamfum-Muyembe, J.J.; Lasarev, M.R.; Boivin, M.J.; Banea, J.P; Tshala-Katumbay, D.D.

    2014-01-01

    Background While risk factors for konzo are known, determinants of cognitive impairment in konzo-affected children remain unknown. Method We anchored cognitive performance (KABC-II scores) to serum levels of free-thyroxine (free-T4), thyroid-stimulating hormone (TSH), albumin, and motor proficiency (BOT-2 scores) in 40 children including 21 with konzo (median age: 9 years) and 19 without konzo (median age: 8 years). A multiple regression model was used to determine variables associated with changes in KABC-II scores. Results Age (β: − 0.818, 95%CI: − 1.48, − 0.152) (p=0.018), gender (β: − 5.72; 95% CI: − 9.87, −1.57 for females) (p=0.009), BOT-2 score (β: 0.390; 95% CI: 0.113, 0.667) (p=0.008), and free-T4 (β: 1.88; 95% CI: 0.009, 3.74) (p=0.049) explained 61.1% of variation in KABC-II scores. Subclinical hypothyroidism was not associated with poor cognition. A crude association was found between serum albumin and KABC-II scores (β: 1.26; 95% CI: 0.136, 2.39) (p=0.029). On spot urinary thiocyanate reached 688 μmol/l in children without konzo and 1032 μmol/L in those with konzo. Conclusion Female gender and low serum albumin are risk factors common to cognitive and proportionally associated motor deficits in children exposed to cassava cyanogens. The two types of deficits may share common mechanisms. PMID:24481810

  18. Enzymatic Synthesis of Apigenin Glucosides by Glucosyltransferase (YjiC) from Bacillus licheniformis DSM 13

    PubMed Central

    Gurung, Rit Bahadur; Kim, Eun-Hee; Oh, Tae-Jin; Sohng, Jae Kyung

    2013-01-01

    Apigenin, a member of the flavone subclass of flavonoids, has long been considered to have various biological activities. Its glucosides, in particular, have been reported to have higher water solubility, increased chemical stability, and enhanced biological activities. Here, the synthesis of apigenin glucosides by the in vitro glucosylation reaction was successfully performed using a UDP-glucosyltransferase YjiC, from Bacillus licheniformis DSM 13. The glucosylation has been confirmed at the phenolic groups of C-4′ and C-7 positions ensuing apigenin 4′-O-glucoside, apigenin 7-O-glucoside and apigenin 4′,7-O-diglucoside as the products leaving the C-5 position unglucosylated. The position of glucosylation and the chemical structures of glucosides were elucidated by liquid chromatography/mass spectroscopy and nuclear magnetic resonance spectroscopy. The parameters such as pH, UDP glucose concentration and time of incubation were also analyzed during this study. PMID:24170092

  19. Absolute Line Intensities in the 2ν 02 Band of Cyanogen Chloride at 12.8 μm

    NASA Astrophysics Data System (ADS)

    Lepère, Muriel; Blanquet, Ghislain; Walrand, Jacques

    2000-05-01

    Absolute line intensities were measured at high resolution with a tunable diode laser. This work concerns the 2ν02 band of cyanogen chloride ClCN in the region 780 cm-1. Thirty-two absorption lines were recorded for the isotopomer 35ClCN and 26 lines for 37ClCN. From the analysis of these lines, we determined the bandstrengths: S0v = 19.14 cm-2 atm-1 for 35ClCN and S0v = 17.84 cm-2 atm-1 for 37ClCN.

  20. Amaranthin in feather cockscombs is synthesized via glucuronylation at the cyclo-DOPA glucoside step in the betacyanin biosynthetic pathway.

    PubMed

    Sasaki, Nobuhiro; Abe, Yutaka; Wada, Katsuhiro; Koda, Takatoshi; Goda, Yukihiro; Adachi, Taiji; Ozeki, Yoshihiro

    2005-12-01

    Uridine 5'-diphosphate (UDP)-glucuronic acid: cyclo-DOPA 5-glucoside glucuronosyltransferase activity was detected in a crude extract prepared from the purple flowers of feather cockscombs. This suggests that the glucuronic acid moiety of amaranthin and its derivatives may be introduced at the cyclo-DOPA glucoside step, but not at the betanidin glucoside step. PMID:16247652

  1. Relationship Between Levels of Cyanide in Sudangrass Hybrids Incorporated into Soil and Suppression of Meloidogyne hapla

    PubMed Central

    Widmer, T. L.; Abawi, G. S.

    2002-01-01

    Sudangrass cv. Trudan 8 has been demonstrated to suppress infection of vegetables by Meloidogyne hapla (Mh). Hydrogen cyanide, released from the degradation of the cyanogenic glucoside (dhurrin) during decomposition of Trudan 8, was the primary factor involved in suppression of Mh on vegetables. The cyanide ion level in leaf tissue of 14 hybrids of sudangrass varied between 0.04 (cv. SX-8) to 1.84 parts per million (cv. 840F). The suppressive activity of the sudangrass hybrids against Mh was assessed in greenhouse tests by incorporating various amounts of leaf tissue into organic soil. After 1 week, eggs of Mh were added to the soil (8 eggs/cm[sup3] soil), which was then planted with lettuce as a bioassay plant. After 8 weeks, the lettuce roots were washed and rated for root-gall severity (RGS). Incorporation of sudangrass tissue resulted in a reduction of RGS up to 54%. There was a correlation between the amount of free cyanide incorporated into the soil and the reduction in RGS. Other green manures of cyanogenic plants tested were white clover, which resulted in a 45% reduction in RGS, and flax, which resulted in a 53% reduction in Mh penetration of lettuce roots. These results suggest that cyanogenic plants have potential as nematicidal green manures. PMID:19265902

  2. Relationship Between Levels of Cyanide in Sudangrass Hybrids Incorporated into Soil and Suppression of Meloidogyne hapla.

    PubMed

    Widmer, T L; Abawi, G S

    2002-03-01

    Sudangrass cv. Trudan 8 has been demonstrated to suppress infection of vegetables by Meloidogyne hapla (Mh). Hydrogen cyanide, released from the degradation of the cyanogenic glucoside (dhurrin) during decomposition of Trudan 8, was the primary factor involved in suppression of Mh on vegetables. The cyanide ion level in leaf tissue of 14 hybrids of sudangrass varied between 0.04 (cv. SX-8) to 1.84 parts per million (cv. 840F). The suppressive activity of the sudangrass hybrids against Mh was assessed in greenhouse tests by incorporating various amounts of leaf tissue into organic soil. After 1 week, eggs of Mh were added to the soil (8 eggs/cm[sup3] soil), which was then planted with lettuce as a bioassay plant. After 8 weeks, the lettuce roots were washed and rated for root-gall severity (RGS). Incorporation of sudangrass tissue resulted in a reduction of RGS up to 54%. There was a correlation between the amount of free cyanide incorporated into the soil and the reduction in RGS. Other green manures of cyanogenic plants tested were white clover, which resulted in a 45% reduction in RGS, and flax, which resulted in a 53% reduction in Mh penetration of lettuce roots. These results suggest that cyanogenic plants have potential as nematicidal green manures. PMID:19265902

  3. Synergic actions of polyphenols and cyanogens of peanut seed coat (Arachis hypogaea) on cytological, biochemical and functional changes in thyroid.

    PubMed

    Chandra, Amar K; Mondal, Chiranjit; Sinha, Sabyasachi; Chakraborty, Arijit; Pearce, Elizabeth N

    2015-03-01

    In animals, long-term feeding with peanut (Arachis hypogaea) seed coats causes hypertrophy and hyperplasia of the thyroid gland. However, to date there have been no detailed studies. Here, we explored the thyroidal effects of dietary peanut seed coats (PSC) in rats. The PSC has high levels of pro-goitrogenic substances including phenolic and other cyanogenic constituents. The PSC was mixed with a standard diet and fed to rats for 30 and 60 days, respectively. Animals fed with the PSC-supplemented diet showed a significant increase in urinary excretion of thiocyanate and iodine, thyroid enlargement, and hypertrophy and/or hyperplasia of thyroid follicles. In addition, there was inhibition of thyroid peroxidase (TPO) activity, 5'-deiodinase-I (DIO1) activity, and (Na+-K+)-ATPase activity in the experimental groups of rats as compared to controls. Furthermore, the PSC fed animals exhibited decreased serum circulating total T4 and T3 levels, severe in the group treated for longer duration. These data indicate that PSC could be a novel disruptor of thyroid function, due to synergistic actions of phenolic as well as cyanogenic constituents. PMID:25872244

  4. Officinalioside, a new lignan glucoside from Borago officinalis L.

    PubMed

    Samy, Mamdouh Nabil; Hamed, Ashraf Nageeb El-Sayed; Sugimoto, Sachiko; Otsuka, Hideaki; Kamel, Mohamed Salah; Matsunami, Katsuyoshi

    2016-01-01

    A new lignan glucoside, officinalioside (1), was isolated from n-BuOH fraction of the aerial parts of Borago officinalis L., together with four known compounds: actinidioionoside (2), roseoside (3), crotalionoside C (4) and kaempferol 3-O-β-D-galactopyranoside (5). The structure of the new compound was established by means of spectroscopic and chemical analyses. Compounds 1 and 2 showed a moderate DPPH radical scavenging activity (IC50: 52.6 ± 1.70 and 41.3 ± 0.25 μM, respectively) comparable with that of the standard trolox (16.6 ± 2.2 μM) without any significant cytotoxicity towards human cell line A549 (IC50 > 100 μM). PMID:26382913

  5. New triterpene glucosides from the roots of Rosa laevigata Michx.

    PubMed

    Yuan, Jing-Quan; Yang, Xin-Zhou; Miao, Jian-Hua; Tang, Chun-Ping; Ke, Chang-Qiang; Zhang, Ji-Bao; Ma, Xiao-Jun; Ye, Yang

    2008-01-01

    Two new ursane-type triterpene glucosides, 2alpha,3alpha,24-trihydroxyurs-12,18-dien-28-oic acid beta-D-glucopyranosyl ester (1) and 2alpha,3alpha,23-trihydroxyurs-12,19(29)-dien-28-oic acid beta-D-glucopyranosyl ester (2), were isolated from the roots of Rosa laevigata, together with three known compounds: 2alpha,3beta,19alpha-trihydroxyurs-12-en-28-oic acid beta-Dglucopyranosyl ester (3), 2alpha,3alpha,19alpha-trihydroxyurs-12-en-28-oic acid beta-D-glucopyranosyl ester (4) and 2alpha,3beta,19alpha,23-tetrahydroxyurs-12-en-28-oic acid beta-D-glucopyranosyl ester (5). The structures of new compounds were established on the basis of detailed 1D and 2D NMR spectroscopic analyses. Compounds 2 and 5 exhibited modest in vitro antifungal activities against Candida albicans and C. krusei. PMID:18830152

  6. Four new neolignan glucosides from the fruits of Arctium lappa.

    PubMed

    Huang, Xiao-Ying; Feng, Zi-Ming; Yang, Ya-Nan; Jiang, Jian-Shuang; Zhang, Pei-Cheng

    2015-05-01

    Four new neolignan glucosides named (7S, 8R)-4,7,9,9'-tetrahydroxy-3,3'-dimethoxy-8-O-4'-neolignan-9'-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (1), (8R)-4,9,9'-trihydroxy-3,3'-dimethoxy-7-oxo-8-O-4'-neolignan-4-O-β-d-glucopyranoside (2), (7R, 8S)-dihydrodehydrodiconiferyl alcohol-7'-oxo-4-O-β-d-glucopyranoside (3), and (7'S, 8'R, 8S)-4,4',9'-trihydroxy-3,3'-dimethoxy-7',9-epoxylignan-7-oxo-4-O-β-d-glucopyranoside (4) were isolated from the fruits of Arctium lappa L. Their structures and absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses (UV, IR, HR-ESI-MS, 1D and 2D NMR, CD), as well as by comparison with known analogues in the literature. PMID:25978776

  7. Chemotaxonomic value of magastigmane glucosides of Cichorium calvum.

    PubMed

    Michalska, Klaudia; Beharav, Alex; Kisiel, Wanda

    2014-03-01

    Morphological characters and molecular analyses of Cichorium calvum and C. pumilum do not allow clear discrimination between these closely related wild species. Therefore, the aim of this study was to characterize the secondary metabolites of C. calvum and to select chemical markers which are unique to this species. From roots of C. calvum, ten sesquiterpene lactones were isolated, including seven lactucin-type guaianolides reported earlier from C. pumilum. Aerial parts also afforded secondary metabolites common to both species, along with the megastigmane glucosides staphylionoside D, saussureoside B and komaroveside A. This is the first report of the occurrence of these norisoprenoids in Cichorium species and the second record of their isolation from plants. Therefore, chemical discrimination of C. calvum is possible on the basis of its norisoprenoid composition. PMID:24689202

  8. Sesamolinol glucoside, disaminyl ether, and other lignans from sesame seeds.

    PubMed

    Grougnet, Raphael; Magiatis, Prokopios; Laborie, Helene; Lazarou, Despina; Papadopoulos, Athanasios; Skaltsounis, Alexios-Leandros

    2012-01-11

    The application of a procedure based on XAD-4 adsorption resin permitted the obtainment of an enriched polyphenolic extract from Sesamum indicum seeds. Chemical analysis of the obtained extract led to the identification of 12 lignans. Among them, 2 lignans, (+)-sesamolinol-4'-O-β-D-glucoside and disaminyl ether, are reported for the first time as natural compounds. Their structure has been determined by spectroscopic methods, mainly by the application of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) techniques [heteronuclear multiple-quantum coherence (HMQC), heteronuclear multiple-bond correlation (HMBC), and nuclear Overhauser effect spectrometry (NOESY)] and mass spectroscopy. The isolated compounds were evaluated for their antimutagenic activity. Among the tested lignans, the most active lignan was found to be sesamolin, followed by sesamolinol and samin, against H(2)O(2). Additionally, some of the tested lignans showed desmutagenic activity against benzo[a]pyrene (BaP). PMID:22148167

  9. Iridoid glucosides with insecticidal activity from Galium melanantherum.

    PubMed

    Tzakou, Olga; Mylonas, Philippos; Vagias, Constantinos; Petrakis, Panos V

    2007-01-01

    The insecticidal activity of the endemic species Galium melanantherum was evaluated against Crematogaster scutellaris ants and Kalotermes flavicollis termites. Iridoid glucosides 1-7 were isolated for the first time as metabolites of the investigated plant, along with the coumarin scopolin. The main components of the extract were found to be the non-acetylated iridoids: geniposidic acid (1), 10-hydroxyloganin (2), deacetyldaphylloside (3), monotropein (4), deacetylasperulosidic acid (5) and scandoside (6), while asperulosidic acid (7) was present only in minute quantities. All isolated metabolites were identified on the basis of their spectral data. Laboratory bioassays revealed significant levels of toxicity for 1-4 against Kalotermes flavicollis termites and Crematogaster scutellaris ants. PMID:17913079

  10. Three new lignan glucosides from the roots of Scutellaria baicalensis.

    PubMed

    Long, Hailin; Zhang, Haijing; Deng, Anjun; Ma, Lin; Wu, Lianqiu; Li, Zhihong; Zhang, Zhihui; Wang, Wenjie; Jiang, Jiandong; Qin, Hailin

    2016-05-01

    Three new lignan glucosides, baicalensinosides A-C (1-3), were isolated from the roots of Scutellaria baicalensis. The structural elucidation was achieved by in-depth spectroscopic examinations and qualitative chemical test. Structurally, these compounds belong to the 3,4-dibenzyltetrahydrofuran-type lignan glycoside with a mono-hydroxyl substitution at the 7'-position of benzylidene group on the numbering system of lignans being one of their shared critical features. The anti-osteoporotic activity of the isolated compounds was assessed in an in vitro osteoprotegerin (OPG) transcriptional activity assay using dual luciferase reporter detection. At 10 μmol/L, compounds 1-3 increased the relative activating ratio of OPG transcription to 1.83, 0.84 and 0.98 times that of the control group, respectively. PMID:27175334

  11. Indole alkaloid glucosides from the roots of Isatis indigotica.

    PubMed

    Liu, Yu-Feng; Chen, Ming-Hua; Lin, Sheng; Li, Yu-Huan; Zhang, Dan; Jiang, Jian-Dong; Shi, Jian-Gong

    2016-01-01

    Five new indole alkaloid glucosides named isatindigotindolosides A-E (1-5), along with three known analogs (6-8), were isolated from an aqueous extract of the Isatis indigotica roots. Their structures including the absolute configurations were determined based on comprehensive spectroscopic data analysis, combined with chemical methods and electronic circular dichroism spectra calculations. In the preliminary assays, compounds 1, 6 and 7 showed antiviral activity against influenza virus A/Hanfang/359/95 (H3N2) with IC50 values of 14.6-33.3 μM. Compound 1 also exhibited inhibitory effect against nitric oxide (NO) production in microglial cell BV2 with an inhibition ratio of 93.0% at 10 μM. PMID:26651370

  12. Three new lignan glucosides from the roots of Scutellaria baicalensis

    PubMed Central

    Long, Hailin; Zhang, Haijing; Deng, Anjun; Ma, Lin; Wu, Lianqiu; Li, Zhihong; Zhang, Zhihui; Wang, Wenjie; Jiang, Jiandong; Qin, Hailin

    2016-01-01

    Three new lignan glucosides, baicalensinosides A–C (1–3), were isolated from the roots of Scutellaria baicalensis. The structural elucidation was achieved by in-depth spectroscopic examinations and qualitative chemical test. Structurally, these compounds belong to the 3,4-dibenzyltetrahydrofuran-type lignan glycoside with a mono-hydroxyl substitution at the 7′-position of benzylidene group on the numbering system of lignans being one of their shared critical features. The anti-osteoporotic activity of the isolated compounds was assessed in an in vitro osteoprotegerin (OPG) transcriptional activity assay using dual luciferase reporter detection. At 10 μmol/L, compounds 1–3 increased the relative activating ratio of OPG transcription to 1.83, 0.84 and 0.98 times that of the control group, respectively. PMID:27175334

  13. Dipasperoside A, a novel pyridine alkaloid-coupled iridoid glucoside from the roots of Dipsacus asper.

    PubMed

    Li, Feng; Tanaka, Ken; Watanabe, Shiro; Tezuka, Yasuhiro; Saiki, Ikuo

    2013-01-01

    A new pyridine alkaloid-coupled iridoid glucoside, dipasperoside A (1), and 20 known compounds (2–21) were isolated from a water extract of Dipsacus asper roots. Compound 1 possessed a unique structural feature with a nicotinic acid nucleus coupled through C-5 with C-7 of a secoiridoid/iridoid glucoside dimer, and esterified with a C-7 hydroxyl group of an iridoid glucoside monomer. All isolates were evaluated for their inhibitory activity against nitric oxide (NO) production in a lipopolysaccharide (LPS)-activated murine macrophage cell line, RAW264.7. PMID:24436964

  14. Olive leaf components apigenin 7-glucoside and luteolin 7-glucoside direct human hematopoietic stem cell differentiation towards erythroid lineage.

    PubMed

    Samet, Imen; Villareal, Myra O; Motojima, Hideko; Han, Junkyu; Sayadi, Sami; Isoda, Hiroko

    2015-06-01

    The generation of blood cellular components from hematopoietic stem cells is important for the therapy of a broad spectrum of hematological disorders. In recent years, several lines of evidence suggested that certain nutrients, vitamins and flavonoids may have important roles in controlling the stem cell fate decision by maintaining their self-renewal or stimulating the lineage-specific differentiation. In this study, main olive leaf phytochemicals oleuropein (Olp), apigenin 7-glucoside (Api7G) and luteolin 7-glucoside (Lut7G) were investigated for their potential effects on hematopoietic stem cell differentiation using both phenotypic and molecular analysis. Oleuropein and the combination of the three compounds enhanced the differentiation of CD34+ cells into myelomonocytic cells and lymphocytes progenitors and inhibited the commitment to megakaryocytic and erythroid lineages. Treatment with Lut7G stimulated both the erythroid and the myeloid differentiation, while treatment with Api7G specifically induced the differentiation of CD34+ cells towards the erythroid lineage and inhibited the myeloid differentiation. Erythroid differentiation induced by Api7G and Lut7G treatments was confirmed by the increase in hemoglobin genes expressions (α-hemoglobin, β-hemoglobin and γ-hemoglobin) and erythroid transcription factor GATA1 expression. As revealed by microarray analysis, the mechanisms underlying the erythroid differentiation-inducing effect of Api7G on hematopoietic stem cells involves the activation of JAK/STAT signaling pathway. These findings prove the differentiation-inducing effects of olive leaf compounds on hematopoietic stem cells and highlight their potential use in the ex vivo generation of blood cells. PMID:26299581

  15. Small intestinal hydrolysis of plant glucosides: higher glucohydrolase activities in rodents than passerine birds.

    PubMed

    Lessner, Krista M; Dearing, M Denise; Izhaki, Ido; Samuni-Blank, Michal; Arad, Zeev; Karasov, William H

    2015-09-01

    Glycosides are a major group of plant secondary compounds characterized by one or more sugars conjugated to a lipophilic, possibly toxic aglycone, which is released upon hydrolysis. We compared small intestinal homogenate hydrolysis activity of three rodent and two avian species against four substrates: amygdalin and sinigrin, two plant-derived glucosides, the sugar lactose, whose hydrolysis models some activity against flavonoid and isoflavonoid glucosides, and the disaccharide sugar maltose (from starch), used as a comparator. Three new findings extend our understanding of physiological processing of plant glucosides: (1) the capacity of passerine birds to hydrolyze plant glucosides seems relatively low, compared with rodents; (2) in this first test of vertebrates' enzymic capacity to hydrolyze glucosinolates, sinigrin hydrolytic capacity seems low; (3) in laboratory mice, hydrolytic activity against lactose resides on the enterocytes' apical membrane facing the intestinal lumen, but activity against amygdalin seems to reside inside enterocytes. PMID:26113142

  16. Thesinine-4'-O-beta-D-glucoside the first glycosylated plant pyrrolizidine alkaloid from Borago officinalis.

    PubMed

    Herrmann, Martina; Joppe, Holger; Schmaus, Gerhard

    2002-06-01

    The glycosylated pyrrolizidine alkaloid, thesinine-4'-O-beta-D-glucoside, has been isolated from the aqueous methanol extract of dried, defatted seeds of Borago officinalis (Boraginaceae). The structure was established by means of spectroscopic and chemical analysis. PMID:12031432

  17. Two new cucurbitacin glucosides, opercurins A and B, from the Brazilian folk medicine "Buchinha" (Luffa operculata).

    PubMed

    Kawahara, Nobuo; Kurata, Atsuyo; Hakamatsuka, Takashi; Sekita, Setsuko; Satake, Motoyoshi

    2004-08-01

    The structures of two new cucurbitacin glucosides designated opercurins A (1) and B (2), isolated from the fruit of Luffa operculata, have been confirmed by extensive spectroscopic investigation. PMID:15305007

  18. A molecular and biochemical analysis of the structure of the cyanogenic beta-glucosidase (linamarase) from cassava (Manihot esculenta Cranz).

    PubMed

    Hughes, M A; Brown, K; Pancoro, A; Murray, B S; Oxtoby, E; Hughes, J

    1992-06-01

    The cyanogenic beta-glucosidase (linamarase) of cassava is responsible for the first step in the sequential break-down of two related cyanoglucosides. Hydrolysis of these cyanoglucosides occurs following tissue damage and leads to the production of hydrocyanic acid. This mechanism is widely regarded as a defense mechanism against predation. A linamarase cDNA clone (pCAS5) was isolated from a cotyledon cDNA library using a white clover beta-glucosidase heterologous probe. The nucleotide and derived amino acid sequence is reported and five putative N-asparagine glycosylation sites are identified. Concanavalin A affinity chromatography and endoglycosidase H digestion demonstrate that linamarase from cassava is glycosylated, having high-mannose-type N-asparagine-linked oligosaccharides. Consistent with this structure and the extracellular location of the active enzyme is the identification of an N-terminal signal peptide on the deduced amino acid sequence of pCAS5. PMID:1586156

  19. Tetrahydroxystilbene Glucoside Improves Neurotrophic Factors Release in Cultured Astroglia.

    PubMed

    Lin, FengQin; Zhou, YanZhen; Shi, WanLan; Wan, YanYing; Zhang, ZeGang; Zhang, Feng

    2016-01-01

    Tetrahydroxystilbene glucoside (TSG), one of the main ingredients of Polygonum multiflorum, has a great number of beneficial effects for health including anti-oxidant, free radicalscavenging and anti-inflammatory properties. However, the potential effects of TSG on neurotrophic factors release remain unclear. In this study, rat primary astroglia cultures were applied to investigate TSG-mediated neurotrophic effects. The protein levels and production of glial cell-line derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in astroglia and the culture medium were determined by western blotting assay and ELISA, respectively. Results indicated that TSG increased the production of neurotrophic factors in a concentration-dependent manner. At different time points of TSG treatment, the BDNF and NGF production in the culture medium was increased 48 h after treatment, while GDNF secretion was initially induced 24 h after TSG treatment. Consistent with the neurotrophic factors release, TSG significantly increased the BDNF, GDNF and NGF protein expressions in astroglia. Furthermore, TSG significantly induced the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and a specific ERK inhibitor-U0126 inhibited TSG-mediated secretion of BDNF, GDNF and NGF. Overall, this study demonstrated that TSG induces astroglia-derived neurotrophic factors release, suggesting TSG might hold a therapeutic potential for neurological disorders. PMID:26295829

  20. Interaction of cyanidin-3-O-glucoside with three proteins.

    PubMed

    Tang, Lin; Li, Shu; Bi, Hongna; Gao, Xin

    2016-04-01

    We studied the binding of cyanidin-3-O-glucoside (C3G) with bovine serum albumin (BSA), hemoglobin (Hb) and myoglobin (Mb), using multi-spectral techniques and molecular modeling. Fluorescence and time-resolved fluorescence studies suggested that C3G quenched BSA, Hb or Mb fluorescence in a static mode with binding constants of 4.159, 0.695 and 1.545 × 10(4) L mol(-1) at 308K, respectively. The thermodynamic parameters represented hydrogen bonds and van der Waals forces dominated the binding. Furthermore, CD, UV-vis, and three-dimensional fluorescence spectra results indicated the secondary structures of BSA, Hb and Mb were partially destroyed by C3G with the α-helix percentage of C3G-Hb and C3G-Mb decreased while that of C3G-BSA was increased. UV-vis spectral results showed these binding interactions partially affected the heme bands of Hb and Mb. In addition, molecular modeling analysis supported the experimental results well. The calculated results of equilibrium fraction showed that the concentration of free C3G in plasma was high enough to be stored and transported from the circulatory system to reach their target sites to provide their therapeutic effects. PMID:26593527

  1. Cucurbitane glucosides from the root of Machilus yaoshansis.

    PubMed

    Gan, Maoluo; Liu, Mingtao; Liu, Bo; Lin, Sheng; Zhang, Yanling; Zi, Jiachen; Song, Weixia; Ye, Fei; Chen, Xiaoguang; Shi, Jiangong

    2011-11-28

    Seven new cucurbitane triterpene glucosides (1-5, 8, and 9) and five known analogues (6, 7, 10, cucurbitacin I 2-O-β-d-glucopyranoside, and khekadaengoside K) have been isolated from an ethanol extract of roots of Machilus yaoshansis. Compounds 1 and 2 have an unusual 16,23:22,25-diepoxy unit, 4 is an uncommon cucurbitane 25-carbamate with the carbamoyl amino group attached at C-24 to form an oxazolidinone ring in the side chain, and 8 is the first example of a trinorcucurbitane derivative. The configurations in several pairs of C-24 epimeric cucurbitacins with 24,25-dihydroxy-22-one side chains were assigned, and the validity of J(23a,24) and J(23b,24) values to differentiate the configuration at C-24 in these cucurbitane derivatives is discussed. Compounds 2-4 showed in vitro activity against protein tyrosine phosphatase 1B with IC50 values of 8.63, 2.81, and 4.26 μM, respectively. Cucurbitacin E 2-O-β-d-glucopyranoside (10) showed selective cytotoxicity against BGC-823 and A549 cancer cells with IC50 values of 4.98 and 3.20 μM, respectively. PMID:22044245

  2. [Selective enrichment of iridoid glucosides in Hedyotis diffusa Willd. by tandem solid phase extraction].

    PubMed

    Zhang, Feng; Guo, Zhimou; Zhang, Feifang; Xue, Xingya; Liang, Xinmiao

    2009-07-01

    A method for selective enrichment of iridoid glucosides in Hedyotis diffusa Willd. by tandem solid phase extraction (SPE) was developed. Oligo(ethylene glycol) (OEG) is a novel type of separation material made in this laboratory. The differences of the surface chemical structures between OEG material and ODS material resulted in their different retention capabilities for iridoid glucosides. Based on the differences, an OEG-ODS solid phase extraction method was designed for selective enrichment of iridoid glucosides. The water extract (150.28 mg) of Hedyotis diffusa Willd. was precipitated by ethanol, and an aliquot (27.03 mg) of the product from the supernatant solution was loaded onto an OEG cartridge and rinsed by 5 mL water. Then, the rinsing solution was loaded onto an ODS cartridge. After it was washed by 5 mL water and eluted by 5 mL methanol, 4.01 mg final product was obtained from the methanol eluent. All the products were characterized by ultra performance liquid chromatography (UPLC), and 14 representative peaks of iridoid glucosides were found. The enrichment results were proved effective by directly comparing the chromatograms each step. To further characterize the enrichment efficiency, the changes of the peak area of iridoid glucosides were investigated. The results showed that the content of 14 iridoid glucosides in the final product reached 6.10 times its original proportion in water extraction product and their recovery was 50.1% on average. Therefore, the iridoid glucosides can be enriched by the tandem solid phase extraction method from water extracting-ethanol precipitating solution of Hedyotis diffusa Willd. with a good selectivity and an acceptable recovery. The proposed method has the advantages of high enrichment efficiency and simple operation. PMID:19938499

  3. In vitro effects of cholesterol β-D-glucoside, cholesterol and cycad phytosterol glucosides on respiration and reactive oxygen species generation in brain mitochondria.

    PubMed

    Panov, Alexander; Kubalik, Nataliya; Brooks, Benjamin R; Shaw, Christopher A

    2010-10-01

    The cluster of neurodegenerative disorders in the western Pacific termed amyotrophic lateral sclerosis-parkinsonism dementia complex (ALS-PDC) has been repeatedly linked to the use of seeds of various species of cycad. Identification and chemical synthesis of the most toxic compounds in the washed cycad seeds, a variant phytosteryl glucosides, and even more toxic cholesterol β-D-glucoside (CG), which is produced by the human parasite Helicobacter pylori, provide a possibility to study in vitro the mechanisms of toxicity of these compounds. We studied in detail the effects of CG on the respiratory activities and generation of reactive oxygen species (ROS) by nonsynaptic brain and heart mitochondria oxidizing various substrates. The stimulatory effects of CG on respiration and ROS generation showed strong substrate dependence, suggesting involvement of succinate dehydrogenase (complex II). Maximal effects on ROS production were observed with 1 μmol CG/1 mg mitochondria. At this concentration the cycad toxins β-sitosterol-β-D-glucoside and stigmasterol-β-D-glucoside had effects on respiration and ROS production similar to CG. However, poor solubility precluded full concentration analysis of these toxins. Cholesterol, stigmasterol and β-sitosterol had no effect on mitochondrial functions studied at concentrations up to 100 μmol/mg protein. Our results suggest that CG may influence mitochondrial functions through changes in the packing of the bulk membrane lipids, as was shown earlier by Deliconstantinos et al. (Biochem Cell Biol 67:16-24, 1989). The neurotoxic effects of phytosteryl glucosides and CG may be associated with increased oxidative damage of neurons. Unlike heart mitochondria, in activated neurons mitochondria specifically increase ROS production associated with succinate oxidation (Panov et al., J Biol Chem 284:14448-14456, 2009). PMID:20938651

  4. Development and application of an enzyme-linked immunosorbent assay (ELISA) for the quantification of amygdalin, a cyanogenic glycoside, in food.

    PubMed

    Bolarinwa, Islamiyat F; Orfila, Caroline; Morgan, Michael R A

    2014-07-01

    Amygdalin is a member of the cyanogenic glycoside group of plant secondary metabolites capable of generating hydrogen cyanide under certain conditions. As a consequence, the cyanogenic glycosides have been associated with incidents of acute and subacute food poisoning. Specific antibodies were raised against an amygdalin-bovine serum albumin immunogen synthesized using a novel approach. The antibodies were used in a microtitration plate enzyme-linked immunosorbent assay (ELISA) for the quantification, for the first time, of amygdalin in commercially available foods. Correlation of results with high-performance liquid chromatography was very high (r = 0.983). The limit of detection of the immunoassay was 200 ± 0.05 pg mL(-1), and the 50% inhibitory concentration of amygdalin was 50 ± 0.02 ng mL(-1), making the ELISA particularly sensitive. PMID:24905893

  5. Primary structure of a histidine-rich proteolytic fragment of human ceruloplasmin. I. Amino acid sequence of the cyanogen bromide peptides.

    PubMed

    Kingston, I B; Kingston, B L; Putnam, F W

    1980-04-10

    A histidine-rich fragment, Cp F5, with a molecular weight of 18,650 was isolated from human ceruloplasmin. It consists of 159 amino acids and contains a possible copper-binding site. The sequence of the first 18 NH2-terminal residues of Cp F5 was determined by automated Edman degradation. Cp F5 was cleaved by cyanogen bromide to produce nine fragments of from 2 to 63 residues. The amino acid sequence of all of the cyanogen bromide fragments was investigated using automated and manual Edman degradation, the fragments being digested with trypsin, chymotrypsin, thermolysin, staphylococcal protease, and pepsin as appropriate. The results, in conjunction with the data on the tryptic peptides reported in the accompanying paper (Kingston, I.B., Kingston, B.L., and Putnam, F.L. (1980) J. Biol. Chem. 255, 2886-2896), establish the complete amino acid sequence of Cp F5. PMID:6987229

  6. The synthesis and antitumor activity of twelve galloyl glucosides.

    PubMed

    Li, Chang-Wei; Dong, Hua-Jin; Cui, Cheng-Bin

    2015-01-01

    Twelve galloyl glucosides 1-12, showing diverse substitution patterns with two or three galloyl groups, were synthesized using commercially available, low-cost D-glucose and gallic acid as starting materials. Among them, three compounds, methyl 3,6-di-O-galloyl-α-D-glucopyranoside (9), ethyl 2,3-di-O-galloyl-α-D-glucopyranoside (11) and ethyl 2,3-di-O-galloyl-β-D-glucopyranoside (12), are new compounds and other six, 1,6-di-O-galloyl-β-D-glucopyranose (1), 1,4,6-tri-O-galloyl-β-D-glucopyranose (2), 1,2-di-O-galloyl-β-D-glucopyranose (3), 1,3-di-O-galloyl-β-D-glucopyranose (4), 1,2,3-tri-O-galloyl-α-D-glucopyranose (6) and methyl 3,4,6-tri-O-galloyl-α-D-glucopyranoside (10), were synthesized for the first time in the present study. In in vitro MTT assay, 1-12 inhibited human cancer K562, HL-60 and HeLa cells with inhibition rates ranging from 64.2% to 92.9% at 100 μg/mL, and their IC50 values were determined to be varied in 17.2-124.7 μM on the tested three human cancer cell lines. In addition, compounds 1-12 inhibited murine sarcoma S180 cells with inhibition rates ranging from 38.7% to 52.8% at 100 μg/mL in the in vitro MTT assay, and in vivo antitumor activity of 1 and 2 was also detected in murine sarcoma S180 tumor-bearing Kunming mice using taxol as positive control. PMID:25633333

  7. Structure-activity relationships of oligo-beta-glucoside elicitors of phytoalexin accumulation in soybean.

    PubMed Central

    Cheong, J J; Birberg, W; Fügedi, P; Pilotti, A; Garegg, P J; Hong, N; Ogawa, T; Hahn, M G

    1991-01-01

    The abilities of a family of chemically synthesized oligo-beta-glucosides, ranging in size from hexamer to decamer, to induce phytoalexin accumulation in soybean cotyledons were investigated to determine which structural elements of the oligoglucosides are important for their biological activity. The results of the biological assays established that the following structural motif is necessary for the oligo-beta-glucosides to have high elicitor activity: [formula; see text] The branched trisaccharide at the nonreducing end of the oligoglucosides was found to be essential for maximum elicitor activity. Substitution of either the nonreducing terminal backbone glucosyl residue or the side-chain glucosyl residue closest to the nonreducing end with glucosaminyl or N-acetylglucosaminyl residues reduced the elicitor activity of the oligoglucosides between 10-fold and 10,000-fold. Elicitor activity was also reduced 1000-fold if the two side-chain glucosyl residues were attached to adjacent backbone glucosyl residues rather than to glucosyl residues separated by an unbranched residue. In contrast, modifications of the reducing terminal glucosyl residue of an elicitor-active hepta-beta-glucoside by conjugation with tyramine and subsequent iodination had no significant effect on the elicitor activity of the hepta-beta-glucoside. These results demonstrate that oligo-beta-glucosides must have a specific structure to trigger the signal transduction pathway, which ultimately leads to the de novo synthesis of phytoalexins in soybean. PMID:1840904

  8. Enzyme bread improvers affect the stability of deoxynivalenol and deoxynivalenol-3-glucoside during breadmaking.

    PubMed

    Vidal, Arnau; Ambrosio, Asier; Sanchis, Vicente; Ramos, Antonio J; Marín, Sonia

    2016-10-01

    The stability of deoxynivalenol (DON) and deoxynivalenol-3-glucoside (DON-3-glucoside) during the breadmaking process was studied. Some enzymes used in the bakery industry were examined to evaluate their effects on DON and DON-3-glucoside. The level of DON in breads without added enzymes was reduced (17-21%). Similarly, the addition of cellulase, protease, lipase and glucose-oxidase did not modify this decreasing trend. The effect of xylanase and α-amylase on DON content depended on the fermentation temperature. These enzymes reduced the DON content by 10-14% at 45°C. In contrast, at 30°C, these enzymes increased the DON content by 13-23%. DON-3-glucoside levels decreased at the end of fermentation, with a final reduction of 19-48% when no enzymes were used. However, the presence of xylanase, α-amylase, cellulase and lipase resulted in bread with greater quantities of DON-3-glucoside when fermentation occurred at 30°C. The results showed that wheat bran and flour may contain hidden DON that may be enzymatically released during the breadmaking process when the fermentation temperature is close to 30°C. PMID:27132852

  9. The cyanogenic syndrome in rubber tree Hevea brasiliensis: tissue-damage-dependent activation of linamarase and hydroxynitrile lyase accelerates hydrogen cyanide release

    PubMed Central

    Kadow, Daniel; Voß, Karsten; Selmar, Dirk; Lieberei, Reinhard

    2012-01-01

    Background and Aims The release of hydrogen cyanide (HCN) from injured plant tissue affects multiple ecological interactions. Plant-derived HCN can act as a defence against herbivores and also plays an important role in plant–pathogen interactions. Crucial for activity as a feeding deterrent is the amount of HCN generated per unit time, referred to as cyanogenic capacity (HCNc). Strong intraspecific variation in HCNc has been observed among cyanogenic plants. This variation, in addition to genotypic variability (e.g. in Trifolium repens), can result from modifications in the expression level of the enzymes involved in either cyanogenic precursor formation or HCN release (as seen in Sorghum bicolor and Phaseolus lunatus). Thus, a modification or modulation of HCNc in reaction to the environment can only be achieved from one to the next generation when under genetic control and within days or hours when transcriptional regulations are involved. In the present study, it is shown that in rubber tree (Hevea brasiliensis) HCNc is modulated by post-translational activity regulation of the key enzymes for cyanide release. Methods Linamarase (LIN) and hydroxynitrile lyase (HNL) activity was determined by colorimetric assays utilizing dissociation of the substrates p-nitrophenyl-β-d-glucopyranoside and acetone cyanohydrin, respectively. Key Results In rubber tree leaves, LIN and HNL show up to ten-fold increased activity in response to tissue damage. This enzyme activation occurs within seconds and results in accelerated HCN formation. It is restricted to the damaged leaf area and depends on the severity of tissue damage. Conclusions LIN and HNL activation (in contrast to genetic and transcriptional regulations) allows an immediate, local and damage type-dependent modulation of the cyanogenic response. Accordingly, this post-translational activation plays a decisive role in the defence of H. brasiliensis against herbivores as well as pathogens and may allow more flexible

  10. A specific, high-affinity binding site for the hepta-beta-glucoside elicitor exists in soybean membranes.

    PubMed Central

    Cheong, J J; Hahn, M G

    1991-01-01

    The presence of a specific binding site for a hepta-beta-glucoside elicitor of phytoalexin accumulation has been demonstrated in soybean microsomal membranes. A tyramine conjugate of the elicitor-active hepta-beta-glucoside was prepared and radiolabeled with 125I. The labeled hepta-beta-glucoside-tyramine conjugate was used as a ligand in binding assays with a total membrane fraction prepared from soybean roots. Binding of the radiolabeled hepta-beta-glucoside elicitor was saturable, reversible, and with an affinity (apparent Kd = 7.5 x 10(-10) M) comparable with the concentration of hepta-beta-glucoside required for biological activity. A single class of hepta-beta-glucoside binding sites was found. The binding site was inactivated by proteolysis and by heat treatment, suggesting that the binding site is a protein or glycoprotein. Competitive inhibition of binding of the radiolabeled hepta-beta-glucoside elicitor by a number of structurally related oligoglucosides demonstrated a direct correlation between the binding affinities and the elicitor activities of these oligoglucosides. Thus, the hepta-beta-glucoside-binding protein fulfills criteria expected of a bona fide receptor for the elicitor-active oligosaccharin. PMID:1840905

  11. Quercetin 3-O-glucoside suppresses epidermal growth factor-induced migration by inhibiting EGFR signaling in pancreatic cancer cells.

    PubMed

    Lee, Jungwhoi; Han, Song-I; Yun, Jeong-Hun; Kim, Jae Hoon

    2015-12-01

    Pancreatic cancer is one of the most dangerous cancers and is associated with a grave prognosis. Despite increased knowledge of the complex signaling networks responsible for progression of pancreatic cancer, many challenging therapies have fallen short of expectations. In this study, we examined the anti-migratory effect of quercetin 3-O-glucoside in epidermal growth factor-induced cell migration by inhibiting EGF receptor (EGFR) signaling in several human pancreatic cancer cell lines. Treatment with quercetin, quercetin 3-O-glucoside, and quercetin 7-O-glucoside differentially suppressed epidermal growth factor-induced migration activity of human pancreatic cancer cells. In particular, quercetin 3-O-glucoside strongly inhibited the infiltration activity of pancreatic cancer cells in a dose-dependent manner. Furthermore, quercetin 3-O-glucoside exerted the anti-migratory effect even at a relatively low dose compared with other forms of quercetin. The anti-tumor effects of quercetin 3-O-glucoside were mediated by selectively inhibiting the EGFR-mediated FAK, AKT, MEK1/2, and ERK1/2 signaling pathway. Combinatorial treatment with quercetin 3-O-glucoside plus gemcitabine showed the synergistic anti-migratory effect on epidermal growth factor-induced cell migration in human pancreatic cancer cell lines. These results suggest that quercetin 3-O-glucoside has potential for anti-metastatic therapy in human pancreatic cancer. PMID:26109002

  12. Metabolic utilization of pyridoxine-beta-glucoside in rats: influence of vitamin B-6 status and route of administration

    SciTech Connect

    Trumbo, P.R.; Gregory, J.F. 3d.

    1988-11-01

    (3H)5'-O-(beta-D-glucopyranosyl) pyridoxine (PN-glucoside) and (14C)pyridoxine (PN) were administered orally or intraperitoneally to vitamin B-6-adequate or -deficient rats. Analysis of intestinal contents and feces indicated effective intestinal absorption of PN-glucoside relative to PN. There was greater retention of 14C than 3H in the liver and carcass regardless of the route of administration of the radiolabeled vitamins. There was no major difference in the relative distribution of 3H and 14C among the vitamin B-6 metabolites in the liver between the treatment groups, and no (3H)PN-glucoside was detected in any of the livers. For all groups, the majority of the 3H administered was detected in the urine within 24 h. Less excretion of both 3H and 14C in the urine was observed for the deficient rats. There was no major difference in the relative proportion of urinary (3H)PN-glucoside or (3H)4-PA between rats fed or injected with the radiolabeled vitamins. These results indicate that vitamin B-6 status influences the clearance of metabolites derived from PN and PN-glucoside, as well as the clearance of intact PN-glucoside. Vitamin B-6 status, however, has little or no effect on the utilization of PN-glucoside. This study also suggests that the intestine is the primary site of the limited conversion of PN-glucoside to biologically active PN in the rat.

  13. Further characterization and regulation of malonyl-coenzyme A: flavonoid glucoside malonyltransferases from parsley cell suspension cultures

    SciTech Connect

    Matern, U.; Feser, C.; Hammer, D.

    1983-10-01

    Two malonyltransferases, malonyl-CoA:flavone/flavonol 7-O-glucoside malonyltransferase and malonyl-CoA:flavonol 3-O-glucoside malonyltransferase, were purified to apparent homogeneity from uv-irradiated parsley cell cultures. Both purified enzymes appear to be specific for flavonoid glycosides. Additional malonyltransferases, active toward several phenol glucosides other than flavonoids, were present in partially purified 7-O-glucoside malonyltransferase preparations. Antibodies raised against the purified 3-O-glucoside malonyltransferase did not inhibit the activity of the 7-O-glucoside malonyltransferase over a wide antibody concentration range. Determination of the rate of synthesis in vivo of the 3-O-glucoside malonyltransferase after ultraviolet light-pulse induction of parsley cells revealed two maxima at 6 and 30 h, respectively. These results indicate that the induced changes in 3-O-glucoside malonyltransferase activity were the consequence of either a repeated change in the rate of synthesis of one enzyme species or changes in the synthesis rates of more than one enzyme species.

  14. Identification of delphinidin 3-O-(6''-O-malonyl)-beta-glucoside-3'-O-beta-glucoside, a postulated intermediate in the biosynthesis of ternatin C5 in the blue petals of Clitoria ternatea (butterfly pea).

    PubMed

    Kazuma, Kohei; Kogawa, Koichiro; Noda, Naonobu; Kato, Naoki; Suzuki, Masahiko

    2004-11-01

    Ternatins are blue anthocyanins found in the petals of Clitoria ternata (butterfly pea). Among them, ternatin C5 (delphinidin 3-O-(6''-O-malonyl)-beta-glucoside-3',5'-di-O-beta-glucoside; 2) has the structure common to all the ternatins, which is characterized by its glucosylation pattern: a 3,3',5'-triglucosylated anthocyanidin. In the course of studying biosynthetic pathways of ternatins, the key enzymatic activities to produce ternatin C5 were discovered in a crude enzyme preparation from the petals of a blue petal line of C. ternatea. When this preparation was tested for activity against several delphinidin glycosides, delphinidin 3-O-(6''-O-malonyl)-beta-glucoside-3'-O-beta-glucoside (6), a postulated intermediate, was found in the reaction mixture, together with three known anthocyanins, which were spectroscopically structurally identified. As a result of structural identification, the following enzymatic activities were identified: UDP-glucose :delphinidin 3-O-(6''-O-malonyl)-beta-glucoside-3'-O-beta-glucoside 5'-O-glucosyltransferase (5'GT), UDP-glucose :delphinidin 3-O-(6''-O-malonyl)-beta-glucoside 3'-O-glucosyltransferase (3'GT), UDP-glucose :delphinidin 3-O-glucosyltransferase, and malonyl-CoA :delphinidin 3-O-beta-glucoside 6''-malonyltransferase. In a mauve petal line, which did not accumulate ternatins but delphinidin 3-O-(6''-O-malonyl)-beta-glucoside in its petal, there were neither 5'GT nor 3'GT activities. Thus, the early biosynthetic pathway of ternatins may be characterized by the stepwise transfer of two glucose residues to 3'- and 5'-position of delphinidin 3-O-(6''-O-malonyl)-beta-glucoside (1; Scheme) from UDP-glucose. PMID:17191814

  15. Implementation of New TPD Analysis Techniques in the Evaluation of Second Order Desorption Kinetics of Cyanogen from Cu(001)

    SciTech Connect

    E Ciftlikli; E Lee; J Lallo; S Rangan; S Senanayake; B Hinch

    2011-12-31

    The interactions of cyanide species with a copper (001) surface were studied with temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). Adsorbed cyanide species (CN{sub (a)}) undergo recombinative desorption evolving molecular cyanogen (C{sub 2}N{sub 2}). As the adsorbed CN species charge upon adsorption, mutually repulsive dipolar interactions lead to a marked desorption energy reduction with increasing CN{sub (a)} coverages. Two new TPD analysis approaches were developed, which used only accurately discernible observables and which do not assume constant desorption energies, E{sub d}, and pre-exponential values, v. These two approaches demonstrated a linear variation of E{sub d} with instantaneous coverage. The first approach involved an analysis of the variations of desorption peak asymmetry with initial CN coverages. The second quantitative approach utilized only temperatures and intensities of TPD peaks, together with deduced surface coverages at the peak maxima, also as a function of initial surface coverages. Parameters derived from the latter approach were utilized as initial inputs for a comprehensive curve fit analysis technique. Excellent fits for all experimental desorption curves were produced in simulations. The curve fit analysis confirms that the activation energy of desorption of 170-180 kJ/mol at low coverage decreases by up to 14-15 kJ/mol at CN saturation.

  16. Variation in cyanogenic glycosides across populations of wild lima beans (Phaseolus lunatus) has no apparent effect on bruchid beetle performance.

    PubMed

    Shlichta, J Gwen; Glauser, Gaetan; Benrey, Betty

    2014-05-01

    Cyanogenic glycosides (CNGs) act as feeding or oviposition deterrents and are toxic after enzymatic hydrolysis, thus negatively affecting herbivore performance. While most studies on CNGs focus on leaf herbivores, here we examined seeds from natural populations of Phaseolus lunatus in Mexico. The predominant CNGs, linamarin and lotaustralin, were quantified for each population by using ultra-high pressure liquid chromatography-mass spectrometry. We also examined whether there was a correlation between the concentration of CNGs and the performance of the Mexican bean beetle, Zabrotes subfasciatus, on seeds from each population(.) The concentrations of CNGs in the seeds were relatively high compared to the leaves and were significantly variable among populations. Surprisingly, this had little effect on the performance of the bruchid beetles. Zabrotes subfasciatus can tolerate high concentrations of CNGs, most likely because of the limited β-glucosidase activity in the seeds. Seed herbivory does not appear to liberate hydrogen cyanide due to the low water content in the seed. This study illustrates the importance of quantifying the natural variation and activity of toxic compounds in order to make relevant biological inferences about their role in defense against herbivores. PMID:24863488

  17. Grappling the High Altitude for Safe Edible Bamboo Shoots with Rich Nutritional Attributes and Escaping Cyanogenic Toxicity

    PubMed Central

    Waikhom, Sayanika Devi; Louis, Bengyella; Sharma, Chandradev K.; Kumari, Pushpa; Somkuwar, Bharat G.; Singh, Mohendro W.; Talukdar, Narayan C.

    2013-01-01

    Consumption of bamboo species with high level of total cyanogenic content (TCC) in Asia by many ethnic groups is significantly associated with food poisoning and occasionally Konzo (a neurological disorder). Adequate characterization of edible bamboo species with low level of TCC and high nutritious attributes is required for consumer's safety as well as for the conservation of the gene pool. Here, we employed morphological descriptors, atomic absorption spectrophotometer, RAPD, and trnL-F intergenic spacer to characterize 15 indigenous edible bamboo species of north-east India. The study indicates that morphologically and genetically evolved edible bamboo species having large and robust bamboo-shoot texture and growing at low altitude contain high level of TCC, low antioxidant properties, and low levels of beneficial macronutrients and micronutrients. Importantly, Dendrocalamus species are shown to be rich in TCC irrespective of the growing altitude while Bambusa species are found to have moderate level of TCC. The findings clearly demonstrated that Chimonobambusa callosa growing at high altitude represents safe edible bamboo species with nutritious attributes. PMID:24350255

  18. Implementation of New TPD Analysis Techniques in the Evaluation of Second Order Desorption Kinetics of Cyanogen from Cu(001)

    SciTech Connect

    Hinch, B.J.; Senanayake, S.; Ciftlikli, E.Z.; Lee, E.Y.M.; Lallo, J.; Rangan, S.

    2010-12-21

    The interactions of cyanide species with a copper (001) surface were studied with temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). Adsorbed cyanide species (CN{sub (a)}) undergo recombinative desorption evolving molecular cyanogen (C{sub 2}N{sub 2}). As the adsorbed CN species charge upon adsorption, mutually repulsive dipolar interactions lead to a marked desorption energy reduction with increasing CN{sub (a)} coverages. Two new TPD analysis approaches were developed, which used only accurately discernible observables and which do not assume constant desorption energies, E{sub d}, and pre-exponential values, v. These two approaches demonstrated a linear variation of E{sub d} with instantaneous coverage. The first approach involved an analysis of the variations of desorption peak asymmetry with initial CN coverages. The second quantitative approach utilized only temperatures and intensities of TPD peaks, together with deduced surface coverages at the peak maxima, also as a function of initial surface coverages. Parameters derived from the latter approach were utilized as initial inputs for a comprehensive curve fit analysis technique. Excellent fits for all experimental desorption curves were produced in simulations. The curve fit analysis confirms that the activation energy of desorption of 170-180 kJ/mol at low coverage decreases by up to 14-15 kJ/mol at CN saturation.

  19. Purification and functional characterization of the first stilbene glucoside-specific β-glucosidase isolated from Lactobacillus kimchi.

    PubMed

    Ko, Jin-A; Park, J Y; Kwon, H J; Ryu, Y B; Jeong, H J; Park, S J; Kim, C Y; Oh, H M; Park, C S; Lim, Y H; Kim, D; Rho, M C; Lee, W S; Kim, Y M

    2014-12-01

    This study aimed to develop viable enzymes for bioconversion of resveratrol-glucoside into resveratrol. Out of 13 bacterial strains tested, Lactobacillus kimchi JB301 could completely convert polydatin into resveratrol. The purified enzyme had an optimum temperature of 30-40°C and optimum pH of pH 5.0 against polydatin. This enzyme showed high substrate specificities towards different substrates in the following order: isorhaponticin>polydatin>mulberroside A>oxyresveratrol-3-O-glucoside. Additionally, it rarely hydrolyzed astringin and desoxyrhaponticin. Based on these catalytic specificities, we suggest this enzyme be named stilbene glucoside-specific β-glucosidase. Furthermore, polydatin extracts from Polygonum cuspidatum were successfully converted to resveratrol with a high yield (of over 99%). Stilbene glucoside-specific β-glucosidase is the first enzyme isolated from lactic acid bacteria capable of bio-converting various stilbene glucosides into stilbene. PMID:25442950

  20. Cyclitol glucosides and their role in the synthesis of a glucan from uridine diphosphate glucose in Phaseolus aureus. Characterization of some cyclitol glucoside and their synthesis

    PubMed Central

    Kemp, Jennifer; Loughman, Brian C.

    1974-01-01

    Short-chained sugar compounds, thought to be involved in the synthesis of callose, were formed in small amounts from UDP-glucose by soluble extracts from hypocotyls of seedlings of Phaseolus aureus. The properties of the glycosides were investigated by treatment with various chemicals and analysis by paper chromatography, g.l.c. and mass spectrometry. The data obtained support the characterization of these compounds as myoinositol-β-glucoside and diglucosylmyoinositol. The cyclitol moiety was provided by the enzyme extract. Free myoinositol was not the immediate substrate but a compound containing myoinositol, isolated from the enzyme extract, may be involved. The method of synthesis of these glucosides is compared with that of other cyclitol glycosides. PMID:4441368

  1. Fate of dietary pyridoxine-beta-glucoside in the lactating rat

    SciTech Connect

    Trumbo, P.R.; Gregory, J.F. III

    1989-01-01

    (/sup 3/H)5'-O-(beta-D-glucopyranosyl) pyridoxine (PN-glucoside) and (/sup 14/C)pyridoxine (PN) were orally administered to lactating rats. Milk was collected from the dam, and the stomach contents and liver were collected from the suckling pups 24 and 48 h after administration. Analysis of the isotopic ratio (/sup 3/H//sup 14/C) in the milk and stomach contents indicated that the secretion of /sup 3/H in the milk was 20-25% as great as the secretion of /sup 14/C. The only labeled form of /sup 3/H and /sup 14/C in the stomach contents was pyridoxal phosphate (PLP), indicating that PN-glucoside was hydrolyzed to PN and subsequently metabolized prior to secretion by the mammary gland. The isotopic ratio in the livers of the pups was similar to that of the stomach contents. Furthermore, the relative distribution of the two isotopes among the hepatic metabolites of the pups was similar. The results of this study indicate that intact PN-glucoside is not secreted in milk, although vitamin B-6 derived from the limited hydrolysis and metabolism of PN-glucoside is delivered to the mammary gland for secretion.

  2. Hybrid reuteransucrase enzymes reveal regions important for glucosidic linkage specificity and the transglucosylation/hydrolysis ratio.

    PubMed

    Kralj, Slavko; van Leeuwen, Sander S; Valk, Vincent; Eeuwema, Wieger; Kamerling, Johannis P; Dijkhuizen, Lubbert

    2008-12-01

    The reuteransucrase enzymes of Lactobacillus reuteri strain 121 (GTFA) and L. reuteri strain ATCC 55730 (GTFO) convert sucrose into alpha-d-glucans (labelled reuterans) with mainly alpha-(1-->4) glucosidic linkages (50% and 70%, respectively), plus alpha-(1-->6) linkages. In the present study, we report a detailed analysis of various hybrid GTFA/O enzymes, resulting in the identification of specific regions in the N-termini of the catalytic domains of these proteins as the main determinants of glucosidic linkage specificity. These regions were divided into three equal parts (A1-3; O1-3), and used to construct six additional GTFA/O hybrids. All hybrid enzymes were able to synthesize alpha-glucans from sucrose, and oligosaccharides from sucrose plus maltose or isomaltose as acceptor substrates. Interestingly, not only the A2/O2 regions, with the three catalytic residues, affect glucosidic linkage specificity, but also the upstream A1/O1 regions make a strong contribution. Some GTFO derived hybrid/mutant enzymes displayed strongly increased transglucosylation/hydrolysis activity ratios. The reduced sucrose hydrolysis allowed the much improved conversion of sucrose into oligo- and polysaccharide products. Thus, the glucosidic linkage specificity and transglucosylation/hydrolysis ratios of reuteransucrase enzymes can be manipulated in a relatively simple manner. This engineering approach has yielded clear changes in oligosaccharide product profiles, as well as a range of novel reuteran products differing in alpha-(1-->4) and alpha-(1-->6) linkage ratios. PMID:19016850

  3. Effect of different exposed lights on quercetin and quercetin glucoside content in onion (Allium cepa L.)

    PubMed Central

    Ko, Eun Young; Nile, Shivraj Hariram; Sharma, Kavita; Li, Guan Hao; Park, Se Won

    2014-01-01

    Quercetin and quercetin glucosides are the major flavonols present in onion (Allium cepa L.) and are predominantly present as quercetin, quercetin-3,4′-diglucoside and quercetin-4′-glucoside. Effect of different light wavelengths on onion after harvest and storage, with fluorescent, blue, red and ultra violet light influenced the quercetin and quercetin glucosides profile. In a peeled onion, all the light treatments elevated quercetin content in bulb. Among them, particularly fluorescent light effect was more eminent which stimulates the maximum synthesis of quercetin in onion. In case of whole onion bulb, skin and pulp showed different responses to light treatment, respectively. The pulp had the highest quercetin glucosides under blue light, whereas the lowest under fluorescent light. Onion skin showed nearly opposite pattern as compared to the pulp. In particular, light treatment proved to be a better way to increase the level of quercetin content in onions which might be utilized for industrial production of bioactive compounds from onion and onion waste products. PMID:26150744

  4. Occurrence of deoxynivalenol and deoxynivalenol-3-glucoside in hard red spring wheat grown in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deoxynivalenol (DON) is a mycotoxin found in wheat that is infected with Fusarium fungus. DON may also be converted to a type of "masked mycotoxin," named deoxynivalenol-3-glucoside (D3G), as a result of detoxification process of the plant. Both DON and D3G are known to be toxic. Due to the lack o...

  5. Effect of different exposed lights on quercetin and quercetin glucoside content in onion (Allium cepa L.).

    PubMed

    Ko, Eun Young; Nile, Shivraj Hariram; Sharma, Kavita; Li, Guan Hao; Park, Se Won

    2015-07-01

    Quercetin and quercetin glucosides are the major flavonols present in onion (Allium cepa L.) and are predominantly present as quercetin, quercetin-3,4'-diglucoside and quercetin-4'-glucoside. Effect of different light wavelengths on onion after harvest and storage, with fluorescent, blue, red and ultra violet light influenced the quercetin and quercetin glucosides profile. In a peeled onion, all the light treatments elevated quercetin content in bulb. Among them, particularly fluorescent light effect was more eminent which stimulates the maximum synthesis of quercetin in onion. In case of whole onion bulb, skin and pulp showed different responses to light treatment, respectively. The pulp had the highest quercetin glucosides under blue light, whereas the lowest under fluorescent light. Onion skin showed nearly opposite pattern as compared to the pulp. In particular, light treatment proved to be a better way to increase the level of quercetin content in onions which might be utilized for industrial production of bioactive compounds from onion and onion waste products. PMID:26150744

  6. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Methyl glucoside-coconut oil ester. 178.3600 Section 178.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Certain Adjuvants and...

  7. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Methyl glucoside-coconut oil ester. 172.816 Section 172.816 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives...

  8. Serotonin 5-O-β-Glucoside and Its N-Methylated Forms in Citrus Genus Plants.

    PubMed

    Servillo, Luigi; Giovane, Alfonso; Casale, Rosario; D'Onofrio, Nunzia; Ferrari, Giovanna; Cautela, Domenico; Balestrieri, Maria Luisa; Castaldo, Domenico

    2015-04-29

    Citrus genus is characterized by a specific presence of indole metabolites deriving from the N-methylation of tryptamine and its hydroxylated form, 5-hydroxytryptamine (serotonin), which are likely involved in plant defense mechanisms. In this study, we identified for the first time the occurrence in Citrus plants of serotonin 5-O-β-glucoside and all its N-methylated derivatives, that is, N-methylserotonin 5-O-β-glucoside, N,N-dimethylserotonin (bufotenine) 5-O-β-glucoside, and N,N,N-trimethylserotonin (bufotenidine) 5-O-β-glucoside. The identification of the glucosylated compounds was based on mass spectrometric studies, hydrolysis by glucosidase, and in some cases, comparison to authentic compounds. Beside leaves, the distribution of the glucosylated forms and their aglycones in some Citrus species was evaluated in flavedo, albedo, juice, and seeds. The simultaneous presence of serotonin and its N-methylated derivatives, together with the corresponding glucosylated forms, is consistent with the occurrence of a metabolic pathway, specific for Citrus, aimed at potentiating the defensive response to biotic stress through the optimization of the production and use of the most toxic of such metabolites. PMID:25893818

  9. Quercetin from shallots (Allium cepa L. var. aggregatum) is more bioavailable than its glucosides.

    PubMed

    Wiczkowski, Wieslaw; Romaszko, Jerzy; Bucinski, Adam; Szawara-Nowak, Dorota; Honke, Joanna; Zielinski, Henryk; Piskula, Mariusz K

    2008-05-01

    The lipophilic character of quercetin suggests that it can cross enterocyte membranes via simple diffusion. Therefore, it should be more bioavailable than its glucosides, which require preliminary hydrolysis or active transport for absorption. However, the published human studies show that quercetin is less bioavailable than its glucosides. Assuming that low bioavailability of quercetin aglycone provided to humans as a pure substance is the result of its low solubility in the digestive tract, we studied its bioavailability from dietary sources in which quercetin was dispersed in the food matrix. In a randomized crossover study, 9 volunteers took a single dose of either shallot flesh (99.2% quercetin glucosides and 0.8% quercetin aglycone) or dry shallot skin (83.3% quercetin aglycone and 16.7% quercetin glucosides), providing 1.4 mg quercetin per kg of body weight. Blood samples were collected before and after consumption of shallot preparations. Plasma quercetin was measured on HPLC with electrochemical detection after plasma enzymatic treatment. The maximum plasma quercetin concentration of 1.02 +/- 0.13 micromol/L was reached at 2.33 +/- 0.50 h after shallot flesh consumption compared with 3.95 +/- 0.62 micromol/L at 2.78 +/- 0.15 h after dry skin consumption. The area under the concentration-time curve after dry skin consumption was 47.23 +/- 7.53 micromol x h(-1) x L(-1) and was significantly higher than that after shallot flesh intake (22.23 +/- 2.32 micromol x h(-1) x L(-1)). When provided along with dietary sources, quercetin aglycone is more bioavailable than its glucosides in humans. Results point to the food matrix as a key factor. PMID:18424596

  10. Genetic diversity analysis of cyanogenic potential (CNp) of root among improved genotypes of cassava using simple sequence repeat markers.

    PubMed

    Moyib, O K; Mkumbira, J; Odunola, O A; Dixon, A G

    2012-12-01

    Cyanogenic potential (CNp) of cassava constitutes a serious problem for over 500 million people who rely on the crop as their main source of calories. Genetic diversity is a key to successful crop improvement for breeding new improved variability for target traits. Forty-three improved genotypes of cassava developed by International Institute of Tropical Agriculture (ITA), Ibadan, were characterized for CNp trait using 35 Simple Sequence.Repeat (SSR) markers. Essential colorimetry picric test was used for evaluation of CNp on a color scale of 1 to 14. The CNp scores obtained ranged from 3 to 9, with a mean score of 5.48 (+/- 0.09) based on Statistical Analysis System (SAS) package. TMS M98/ 0068 (4.0 +/- 0.25) was identified as the best genotype with low CNp while TMS M98/0028 (7.75 +/- 0.25) was the worst. The 43 genotypes were assigned into 7 phenotypic groups based on rank-sum analysis in SAS. Dissimilarity analysis representatives for windows generated a phylogenetic tree with 5 clusters which represented hybridizing groups. Each of the clusters (except 4) contained low CNp genotypes that could be used for improving the high CNp genotypes in the same or near cluster. The scatter plot of the genotypes showed that there was little or no demarcation for phenotypic CNp groupings in the molecular groupings. The result of this study demonstrated that SSR markers are powerful tools for the assessment of genetic variability, and proper identification and selection of parents for genetic improvement of low CNp trait among the IITA cassava collection. PMID:23678653

  11. C-Terminal Protein Characterization by Mass Spectrometry: Isolation of C-Terminal Fragments from Cyanogen Bromide-Cleaved Protein

    PubMed Central

    Nika, Heinz; Hawke, David H.; Angeletti, Ruth Hogue

    2014-01-01

    A sample preparation method for protein C-terminal peptide isolation from cyanogen bromide (CNBr) digests has been developed. In this strategy, the analyte was reduced and carboxyamidomethylated, followed by CNBr cleavage in a one-pot reaction scheme. The digest was then adsorbed on ZipTipC18 pipette tips for conjugation of the homoserine lactone-terminated peptides with 2,2′-dithiobis (ethylamine) dihydrochloride, followed by reductive release of 2-aminoethanethiol from the derivatives. The thiol-functionalized internal and N-terminal peptides were scavenged on activated thiol sepharose, leaving the C-terminal peptide in the flow-through fraction. The use of reversed-phase supports as a venue for peptide derivatization enabled facile optimization of the individual reaction steps for throughput and completeness of reaction. Reagents were replaced directly on the support, allowing the reactions to proceed at minimal sample loss. By this sequence of solid-phase reactions, the C-terminal peptide could be recognized uniquely in mass spectra of unfractionated digests by its unaltered mass signature. The use of the sample preparation method was demonstrated with low-level amounts of a whole, intact model protein. The C-terminal fragments were retrieved selectively and efficiently from the affinity support. The use of covalent chromatography for C-terminal peptide purification enabled recovery of the depleted material for further chemical and/or enzymatic manipulation. The sample preparation method provides for robustness and simplicity of operation and is anticipated to be expanded to gel-separated proteins and in a scaled-up format to high-throughput protein profiling in complex biological mixtures. PMID:24688319

  12. Bioavailability of cyanide after consumption of a single meal of foods containing high levels of cyanogenic glycosides: a crossover study in humans.

    PubMed

    Abraham, Klaus; Buhrke, Thorsten; Lampen, Alfonso

    2016-03-01

    The acute toxicity of cyanide is determined by its peak levels reached in the body. Compared to the ingestion of free cyanide, lower peak levels may be expected after consumption of foods containing cyanogenic glycosides with the same equivalent dose of cyanide. This is due to possible delayed and/or incomplete release of cyanide from the cyanogenic glycosides depending on many factors. Data on bioavailability of cyanide after consumption of foods containing high levels of cyanogenic glycosides as presented herein were necessary to allow a meaningful risk assessment for these foods. A crossover study was carried out in 12 healthy adults who consumed persipan paste (equivalent total cyanide: 68 mg/kg), linseed (220 mg/kg), bitter apricot kernels (about 3250 mg/kg), and fresh cassava roots (76-150 mg/kg), with each "meal" containing equivalents of 6.8 mg cyanide. Cyanide levels were determined in whole blood using a GC-MS method with K(13)C(15)N as internal standard. Mean levels of cyanide at the different time points were highest after consumption of cassava (15.4 µM, after 37.5 min) and bitter apricot kernels (14.3 µM, after 20 min), followed by linseed (5.7 µM, after 40 min) and 100 g persipan (1.3 µM, after 105 min). The double dose of 13.6 mg cyanide eaten with 200 g persipan paste resulted in a mean peak level of 2.9 µM (after 150 min). An acute reference dose of 0.075 mg/kg body weight was derived being valid for a single application/meal of cyanides or hydrocyanic acid as well as of unprocessed foods with cyanogenic glycosides also containing the accompanying intact β-glucosidase. For some of these foods, this approach may be overly conservative due to delayed release of cyanide, as demonstrated for linseed. In case of missing or inactivated β-glucosidase, the hazard potential is much lower. PMID:25708890

  13. 4-Pentafluoroethylumbelliferyl-beta-D-glucoside as a new fluorogenic substrate for acid beta-D-glucosidase.

    PubMed

    Tsvetkova, I V; Karpova, E A; Dudukina, T V; Voznyi, Y V

    1996-04-30

    4-Pentafluoroethylumbelliferyl-beta-D-glucoside is proposed as an efficient substrate for human leukocyte acid beta-glucosidase. Its synthesis is described. This substrate was compared directly with 4-trifluoromethylumbelliferyl-beta-D-glucoside synthesized by us earlier and with 4-methylumbelliferyl-beta-D-glucoside which is commonly used for acid beta-glucosidase activity assay. The specific activity of acid beta-glucosidase with 4-pentafluoroethylumbelliferyl-beta-D-glucoside was 3- and 8-fold higher than it was with the substrates mentioned above. The kinetic parameters KM and VMAX for human leukocyte acid beta-glucosidase with the three substrates was determined. One possible application of the newly synthesized substrate is its use in the diagnosis of acid beta-glucosidase hereditary deficiency (Gaucher's disease). PMID:8740577

  14. Enzymatic synthesis, structural characterization and antioxidant capacity assessment of a new lipophilic malvidin-3-glucoside-oleic acid conjugate.

    PubMed

    Cruz, Luis; Fernandes, Iva; Guimarães, Marta; de Freitas, Victor; Mateus, Nuno

    2016-06-15

    The chemical modification of anthocyanins (water-soluble pigments) into more lipophilic compounds is very important to expand their application in the food, medical and cosmetic industries. In this work, the synthesis of a pure malvidin-3-glucoside-oleic acid ester derivative was achieved by enzymatic catalysis. This approach allowed us to synthesize a novel compound, malvidin-3-O-(6''-oleoyl)glucoside (Mv3glc-OA), which was structurally characterized by mass spectrometry and for the first time by NMR spectroscopy. The enzymatic reaction revealed to be regioselective giving only one ester product. Antioxidant features of the malvidin-3-glucoside lipophilic derivative by means of DPPH, FRAP and lipid peroxidation assays were assessed, which confirmed that the structural modification of the genuine malvidin-3-glucoside into a more lipophilic compound did not compromise its antioxidant potential and protected more effectively a lipidic substrate from oxidation, which is an important insight for future technological applications. PMID:27220831

  15. Effective catalytic conversion of cellulose into high yields of methyl glucosides over sulfonated carbon based catalyst.

    PubMed

    Dora, Sambha; Bhaskar, Thallada; Singh, Rawel; Naik, Desavath Viswanatha; Adhikari, Dilip Kumar

    2012-09-01

    An amorphous carbon based catalyst was prepared by sulfonation of the bio-char obtained from fast pyrolysis (N(2) atm; ≈ 550°C) of biomass. The sulfonated carbon catalyst contained high acidity of 6.28 mmol/g as determined by temperature programmed desorption of ammonia of sulfonated carbon catalyst and exhibited high catalytic performance for the hydrolysis of cellulose. Amorphous carbon based catalyst containing -SO(3)H groups was successfully tested and the complete conversion of cellulose in methanol at moderate temperatures with high yields ca. ≥ 90% of α, β-methyl glucosides in short reaction times was achieved. The methyl glucosides formed in methanol are more stable for further conversion than the products formed in water. The carbon catalyst was demonstrated to be stable for five cycles with slight loss in catalytic activity. The utilization of bio-char as a sulfonated carbon catalyst provides a green and efficient process for cellulose conversion. PMID:22776237

  16. Biosynthesis of isoxazolin-5-one and 3-nitropropanoic acid containing glucosides in juvenile Chrysomelina.

    PubMed

    Becker, Tobias; Ploss, Kerstin; Boland, Wilhelm

    2016-07-14

    Stable-isotope-labeled precursors were used to establish the biosynthetic pathway leading from β-alanine towards isoxazolin-5-one glucoside 1 and its 3-nitropropanoate (3-NPA) ester 2 in Chrysomelina larvae. Both structural elements originate from sequestered plant-derived β-alanine or from propanoyl-CoA that is derived from the degradation of some essential amino acids, e.g. valine. β-Alanine is converted into 3-NPA and isoxazolinone 5 by consecutive oxidations of the amino group of β-Ala. Substituting the diphospho group of α-UDP-glucose with 5 generates the isoxazolin-5-one glucoside 1, which serves in the circulating hemolymph of the larva as a platform for esterification with 3-nitropropanoyl-CoA. The pathway was validated with larvae of Phaedon cochleariae, Chrysomela populi as well as Gastrophysa viridula. PMID:27272952

  17. Biosynthesis of Dehydrodiconiferyl Alcohol Glucosides: Implications for the Control of Tobacco Cell Growth 1

    PubMed Central

    Orr, John D.; Lynn, David G.

    1992-01-01

    The dehydrodiconiferyl alcohol glucosides A and B are factors isolated from transformed Vinca rosea tumor cells that can replace the cytokinin requirement for growth of tobacco (Nicotiana tabacum) pith and callus cells in culture. These factors, present in tobacco pith cells, have their concentrations elevated approximately 2 orders of magnitude after cytokinin exposure. Biosynthesis experiments showed that these compounds are not cell wall fragments, as previously suggested, but are produced directly from coniferyl alcohol. Their synthesis is probably associated with the existing pathway for cell wall biosynthesis in both Vinca tumors and tobacco pith explants. The pathway requires only two steps, the dimerization of coniferyl alcohol by a soluble intracellular peroxidase and subsequent glycosylation. Biosynthetic experiments suggested that dehydrodiconiferyl alcohol glucoside breakdown was very slow and control of its concentration was exerted through restricted availability of coniferyl alcohol. PMID:16668635

  18. Hepatoprotective activity of twelve novel 7'-hydroxy lignan glucosides from Arctii Fructus.

    PubMed

    Yang, Ya-Nan; Huang, Xiao-Ying; Feng, Zi-Ming; Jiang, Jian-Shuang; Zhang, Pei-Cheng

    2014-09-17

    Twelve novel 7'-hydroxy lignan glucosides (1-12), including two benzofuran-type neolignans, two 8-O-4' neolignans, two dibenzylbutyrolactone lignans, and six tetrahydrofuranoid lignans, together with six known lignan glucosides (13-18), were isolated from the fruit of Arctium lappa L. (Asteraceae), commonly known as Arctii Fructus. Their structures were elucidated using spectroscopy (1D and 2D NMR, MS, IR, ORD, and UV) and on the basis of chemical evidence. The absolute configurations of compounds 1-12 were confirmed using rotating frame nuclear overhauser effect spectroscopy (ROESY), the circular dichroic (CD) exciton chirality method, and Rh2(OCOCF3)4-induced CD spectrum analysis. All of the isolated compounds were tested for hepatoprotective effects against D-galactosamine-induced cytotoxicity in HL-7702 hepatic cells. Compounds 1, 2, 7-12, and 17 showed significantly stronger hepatoprotective activity than the positive control bicyclol at a concentration of 1 × 10(-5) M. PMID:25180661

  19. Exclusive accumulation of Z-isomers of monolignols and their glucosides in bark of Fagus grandifolia

    NASA Technical Reports Server (NTRS)

    Lewis, N. G.; Inciong, E. J.; Ohashi, H.; Towers, G. H.; Yamamoto, E.

    1988-01-01

    In addition to Z-coniferyl and Z-sinapyl alcohols, bark extracts of Fagus grandifolia also contain significant amounts of the glucosides, Z-coniferin, Z-isoconiferin (previously called faguside) and Z-syringin. The corresponding E-isomers of these glucosides do not accumulate to a detectable level. The accumulation of the Z-isomers suggests that either they are not lignin precursors or that they are reservoirs of monolignols for subsequent lignin biosynthesis; it is not possible to distinguish between these alternatives. The co-occurrence of Z-coniferin and Z-isoconiferin demonstrate that glucosylation of monolignols can occur at either the phenolic or the allylic hydroxyl groups.

  20. Synthesis and properties of carbonylbis(methionyl)insulin, a proinsulin analogue which is convertible to insulin by cyanogen bromide cleavage.

    PubMed

    Busse, W D; Carpenter, F H

    1976-04-20

    The preparation and use of carbonylbis (L-methionine p-nitrophenyl ester) as a reversible cross-linking reagent for insulin are described. The reaction of 1 equiv of reagent with zinc insulin in dimethylformamide in the presence of triethylamine yields as one of the products NalphaA1, NepsilonB29-carbonylbis(methionyl)insulin, (CBM-insulin). The CBM-insulin was characterized by end group analysis and by the products formed on tryptic and chymotryptic cleavage. It possessed 91% of the immunological and 6.5% of the hormonal activity of insulin. Treatment of CBM-insulin with cyanogen bromide (CNBr) in 70% formic acid for 1 h resulted in nearly complete removal of the methionine bridge to yield insulin. A small amount of a side product was removed on DEAE-cellulose at pH 7.2 to give an overall recovery of insulin of 70-80%. Oxidative sulfitolyses of CBM-insulin gave the hexa(S-sulfonate) which was reduced with dithiothreitol to yield reduced CBM-insulin. The latter compound, containing 6 sulfhydryls, exhibited a pH-dependent circular dichroic spectrum. The form at pH 10 exhibited a spectrum typical of random coil which was converted to a form at pH 7.8 which was characterized by a negative extremum at 213 nm. The change in the spectrum at 213 nm with pH was characterized by an apparent pKa of 8.5. Studies on the reoxidation of reduced CBM-insulin were performed at pH values between 7.8 and 10 and at protein concentrations of 0.01-1 mg/ml. The best yields (ca. 85%) of the correctly paired disulfide bonds were obtained in reoxidations at pH 9.5-10 at protein concentration of 0.01-0.1 mg/ml. CBM-insulin, which had been isolated from reoxidation at high pH of the reduced CBM-insulin, was cleaved by CNBr to yield a fully active insulin in an overall yield of 60% from the reduced CBM-insulin. PMID:5108

  1. A new hydroxyjasmone glucoside and its related compounds from the leaf of thyme.

    PubMed

    Kitajima, Junichi; Ishikawa, Toru; Urabe, Atushi

    2004-08-01

    From the polar portion of the methanol extract of thyme (leaf of Thymus vulgaris; Labiatae), which has been used as a stomachic, carminative, a component of prepared cough tea, and as a spice, a new hydroxyjasmone glucoside, (Z)-5'-hydroxyjasmone 5'-O-beta-D-glucopyranoside was isolated together with five related compounds and four aromatic compounds. The structures of the new compound was clarified by spectral investigation. PMID:15305005

  2. Regulation of gene expression: cryptic β-glucoside (bgl) operon of Escherichia coli as a paradigm.

    PubMed

    Harwani, Dharmesh

    2014-01-01

    Bacteria have evolved various mechanisms to extract utilizable substrates from available resources and consequently acquire fitness advantage over competitors. One of the strategies is the exploitation of cryptic cellular functions encoded by genetic systems that are silent under laboratory conditions, such as the bgl (β-glucoside) operon of E. coli. The bgl operon of Escherichia coli, involved in the uptake and utilization of aromatic β-glucosides salicin and arbutin, is maintained in a silent state in the wild type organism by the presence of structural elements in the regulatory region. This operon can be activated by mutations that disrupt these negative elements. The fact that the silent bgl operon is retained without accumulating deleterious mutations seems paradoxical from an evolutionary view point. Although this operon appears to be silent, specific physiological conditions might be able to regulate its expression and/or the operon might be carrying out function(s) apart from the utilization of aromatic β-glucosides. This is consistent with the observations that the activated operon confers a Growth Advantage in Stationary Phase (GASP) phenotype to Bgl(+) cells and exerts its regulation on at least twelve downstream target genes. PMID:25763016

  3. Modulation of protein tyrosine nitration and inflammatory mediators by isoprenylhydroquinone glucoside.

    PubMed

    Olmos, Ana; Giner, Rosa-María; Recio, María-Carmen; Ríos, José-Luis; Máñez, Salvador

    2007-03-01

    The nitration of tyrosine caused by peroxynitrite and other reactive nitrogen species is clearly detrimental for some physiological processes; however, its signalling role is still open to controversy. Among the natural phenolics known for their ability to oppose free tyrosine nitration, isoprenylhydroquinone glucoside is investigated due to its unusual structure, which contains a simple hydroxybenzene alkylated by a hemiterpenoid moiety. This hydroquinone was shown to be an effective inhibitor of peroxynitrite-induced protein tyrosine nitration in 3T3 fibroblasts. When tested on bovine seroalbumin nitration, however, the potency was reduced by half and the effect was almost abolished in the presence of bicarbonate. In contrast, addition of this anion had no effect on the nitrite/hydrogen peroxide/hemin system. Isoprenylhydroquinone glucoside was also active in the microM range on intra- and extracellular protein-bound tyrosine nitration by phorbol 12-myristate 13-acetate-stimulated neutrophils. The effects on nitric oxide synthase expression, interleukin-1beta and tumor necrosis factor-alpha production by lipopolysaccharide-stimulated macrophages were quite moderate. Thus, isoprenylhydroquinone glucoside is an inhibitor of protein nitration in situ, but lacks effect on the generation of either nitric oxide or inflammatory cytokines. PMID:17161592

  4. Analysis of iridoid glucosides from Paederia scandens using HPLC-ESI-MS/MS.

    PubMed

    Wu, Zhi-Jun; Wang, Jian-Hua; Fang, Dong-Mei; Zhang, Guo-Lin

    2013-04-01

    Iridoid glycosides are an important class of natural products and have many biological activities. Iridoid glucosides in an extract of the plant species Paederia scandens were investigated using reversed-phase high performance liquid chromatography and electrospray quadrupole time-of-flight-type tandem mass spectrometry. The elemental composition of most of the compounds was determined by accurate mass and relative isotopic abundance (RIA) measurements. In positive ion mode, the fragmentation of [M+NH4](+) precursor ions was carried out using low energy collision-induced electrospray ionization tandem spectrometry. The neutral losses of NH3, H2O, Glc, and the side chain of the iridoid moiety were the main fragmentation patterns observed. For simple iridoid glycosides, the main differences were related to the side chains. Fragmentation of the [M-H](-)precursor ions was achieved for the compounds possibly having phenolic acid group. The connection order of the iridoid, sugar, and phenolic acid moieties, and the linkage of the 6-OH group of the sugar to the phenolic acid were unambiguously confirmed using a combination of MS/MS spectra in both positive and negative ion modes, and our previous work. For some trace dimeric iridoid glucosides, the connection order between the asperuloside and paederoside moieties was determined by the characteristic product ions; this was supported by D-labeling experiments. A total of 24 iridoid glucosides, including 14 new species, were identified or tentatively characterized based on exact mass, RIA values, tandem mass spectra, and D-labeling experiments. PMID:23466447

  5. Diversity of sugar acceptor of glycosyltransferase 1 from Bacillus cereus and its application for glucoside synthesis.

    PubMed

    Chiu, Hsi-Ho; Shen, Mo-Yuan; Liu, Yuan-Ting; Fu, Yu-Lieh; Chiu, Yu-An; Chen, Ya-Huei; Huang, Chin-Ping; Li, Yaw-Kuen

    2016-05-01

    Glycosyltransferase 1 from Bacillus cereus (BcGT1) catalyzes the transfer of a glucosyl moiety from uridine diphosphate glucose (UDP-glucose) to various acceptors; it was expressed and characterized. The specificity of acceptors was found to be broad: more than 20 compounds classified into O-, S-, and N-linkage glucosides can be prepared with BcGT1 catalysis. Based on this work, we conclude that the corresponding acceptors of these compounds must possess the following features: (1) the acceptors must contain at least one aromatic or fused-aromatic or heteroaromatic ring; (2) the reactive hydroxyl or sulfhydryl or amino group can attach either on the aromatic ring or on its aliphatic side chain; and (3) the acceptors can be a primary, secondary, or even a tertiary amine. Four representative acceptors-fluorescein methyl ester, 17-β-estradiol, 7-mercapto-4-methylcoumarin, and 6-benzylaminopurine-were chosen as a candidate acceptor for O-, S-, and N-glucosidation, respectively. These enzymatic products were purified and the structures were confirmed with mass and NMR spectra. As all isolated glucosides are β-anomers, BcGT1 is confirmed to be an inverting enzyme. This study not only demonstrates the substrate promiscuity of BcGT1 but also showed the great application prospect of this enzyme in bioconversion of valuable bioactive molecules. PMID:26795959

  6. Quantitative Analysis of Phenylpropanoid Glycerol Glucosides in Different Organs of Easter Lily (Lilium longiflorum Thunb.).

    PubMed

    Munafo, John P; Gianfagna, Thomas J

    2015-05-20

    The Easter lily (Lilium longiflorum Thunb.) is esteemed worldwide as an attractive ornamental plant, and the flower buds and bulbs are used for both culinary and medicinal purposes in many parts of the world. L. longiflorum contains significant amounts of phenylpropanoid glycerol glucosides, a group of compounds that may contribute to plant pathogen defense, ultraviolet/high-intensity visible light (UV/high light) protection, and the purported medicinal uses of lilies. To define the natural distribution of these compounds within the plant, a liquid chromatography-mass spectrometry (LC-MS) method performed in selected ion monitoring (SIM) mode was employed for the quantitative analysis of five phenylpropanoid glycerol glucosides, namely, (2S)-1-O-caffeoyl-2-O-β-D-glucopyranosylglycerol, 1; (2R)-1-O-β-D-glucopyranosyl-2-O-p-coumaroylglycerol, 2; (2S)-1-O-p-coumaroyl-2-O-β-D-glucopyranosylglycerol, 3; (2S)-1-O-caffeoyl-2-O-β-D-glucopyranosyl-3-O-acetylglycerol, 4; and (2S)-1-O-p-coumaroyl-2-O-β-D-glucopyranosyl-3-O-acetylglycerol, 5, in the different organs of L. longiflorum. The p-coumaroyl-based 3 and its acetylated derivative 5 were determined to be the most abundant of the phenylpropanoid glycerol glucosides found in Easter lily bulbs, at 776.3 ± 8.4 and 650.7 ± 32.6 μg/g dry weight, respectively. The acetylated p-coumaroyl- and caffeoyl-based derivatives, 5 and 4, accumulated to the highest concentration in the closed flower buds, at 4925.2 ± 512.8 and 3216.8 ± 406.4 μg/g dry weight, respectively. Compound 4, followed by 5 and 1, proved to be the most abundant in the mature flowers, occurring at 6006.2 ± 625.8, 2160.3 ± 556.5, and 1535.8 ± 174.1 μg/g dry weight, respectively. Total concentrations of the phenylpropanoid glycerol glucosides were 10-100-fold higher in the above-ground plant organs as compared to the bulbs and fleshy roots. Two of the five compounds, 1 and 2, were identified in L. longiflorum for the first time. The quantitative

  7. Platinum and rhenium extraction from a spent refinery catalyst using Bacillus megaterium as a cyanogenic bacterium: statistical modeling and process optimization.

    PubMed

    Motaghed, M; Mousavi, S M; Rastegar, S O; Shojaosadati, S A

    2014-11-01

    The present study evaluated the potential of Bacillus megaterium as a cyanogenic bacterium to produce cyanide for solubilization of platinum and rhenium from a spent refinery catalyst. Response surface methodology was applied to study the effects and interaction between two main effective parameters including initial glycine concentration and pulp density. Maximum Pt and Re recovery was obtained 15.7% and 98%, respectively, under optimum conditions of 12.8 g/l initial glycine concentration and 4% (w/v) pulp density after 7 days. Increasing the free cyanide concentration to 3.6 mg/l, varying the pH from 6.7 to 9, and increasing the dissolved oxygen from 2 to 5mg/l demonstrated the growth characteristics of B. megaterium during bioleaching process. The modified shrinking core model was used to determine the rate limiting step of the process. It was found that diffusion through the product layer is the rate controlling step. PMID:25226056

  8. Chemical Synthesis of Deoxynivalenol-3-β-d-[(13)C₆]-glucoside and Application in Stable Isotope Dilution Assays.

    PubMed

    Habler, Katharina; Frank, Oliver; Rychlik, Michael

    2016-01-01

    Modified mycotoxins have been gaining importance in recent years and present a certain challenge in LC-MS/MS analysis. Due to the previous lack of a labeled isotopologue of the modified mycotoxin deoxynivalenol-3-glucoside, in our study we synthesized the first (13)C-labeled internal standard. Therefore, we used the Königs-Knorr method to synthesize deoxynivalenol-3-β-d-[(13)C₆]-glucoside originated from unlabeled deoxynivalenol and [(13)C₆]-labeled glucose. Using the synthesized isotopically-labeled standard deoxynivalenol-3-β-d-[(13)C₆]-glucoside and the purchased labeled standard [(13)C15]-deoxynivalenol, a stable isotope dilution LC-MS/MS method was firstly developed for deoxynivalenol-3-glucoside and deoxynivalenol in beer. The preparation and purification of beer samples was based on a solid phase extraction. The validation data of the newly developed method gave satisfying results. Intra- and interday precision studies revealed relative standard deviations below 0.5% and 7%, respectively. The recoveries ranged for both analytes between 97% and 112%. The stable isotope dilution assay was applied to various beer samples from four different countries. In summary, deoxynivalenol-3-glucoside and deoxynivalenol mostly appeared together in varying molar ratios but were quantified in rather low contents in the investigated beers. PMID:27355938

  9. Enzymatic synthesis of stable, odorless, and powdered furanone glucosides by sucrose phosphorylase.

    PubMed

    Kitao, S; Matsudo, T; Sasaki, T; Koga, T; Kawamura, M

    2000-01-01

    Sucrose phosphorylase from Leuconostoc mesenteroides catalyzed transglucosylation from sucrose to 4-hydroxy-3(2H)-furanone derivatives. When 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) and 2-ethyl-4-hydroxy-5-methyl-3(2H)-furanone or 5-ethyl-4-hydroxy-2-methyl-3(2H)-furanone (EHMF) were used as acceptors, their transfer ratios were more than 45%. In the case of glucosylation of HDMF, the major transfer product was identified as 2,5-dimethyl-3(2H)-furanone 4-O-alpha-D-glucopyranoside (DMF-G). In the case of glucosylation of EHMF, two major transfer products were obtained, and their structures were identified as 2-ethyl-5-methyl-3(2H)-furanone 4-O-alpha-D-glucopyranoside (2E5MF-G) and 5-ethyl-2-methyl-3(2H)-furanone 4-O-alpha-D-glucopyranoside (5E2MF-G) on the bases of spectrometric investigations. These glucosides were more stable than each aglycone. The glucosylated HDMF, DMF-G, was an odorless chemical, on the other hand, HDMF had a pineapple flavor. The glucosylated EHMF (EMF-G) were white odorless powders, though aglycone EHMF was a pale yellow syrup like a caramel with an intense sweet odor. Although DMF-G and EMF-G showed little radical-scavenging activity, hydrolyzates of these glucosides by an intestinal acetone powder from pigs had antioxidative activity as well as their aglycones. It was suggested that these glucosides improved some physical properties and may become prodrugs by glucosylation. PMID:10705458

  10. On the masked mycotoxin zearalenone-14-glucoside. Does the mask truly hide?

    PubMed

    Dellafiora, Luca; Perotti, Alessio; Galaverna, Gianni; Buschini, Annamaria; Dall'Asta, Chiara

    2016-03-01

    In the matter of foodborne mycotoxins, beside a number of regulated compounds, regulations are totally missing for phase-II plant metabolites--the toxicological knowledge of which is still in its infancy. Currently, zearalenone-14-glucoside is in the pipeline and its toxicological role is under a glowing scientific debate. In our work it clearly showed high toxicological concerns as it is prone to conversion to well-known toxic compounds (i.e. zearalenone and both zearalenol isomers) when exposed to breast cancer cells culture. The need of future risk assessment studies has been pointed out accordingly. PMID:26792714

  11. A new indole alkaloidal glucoside from the aerial parts of Clematis terniflora DC.

    PubMed

    Li, Wen-Ting; Yang, Bing-Xian; Zhu, Wei; Gong, Ming-Hua; Xu, Xiang-Dong; Lu, Xiang-Hong; Sun, Lian-Li; Tian, Jing-Kui; Zhang, Lin

    2013-01-01

    A new indole alkaloidal glucoside together with three known compounds aurantiamide acetate (2), eleutheroside E (3) and 1-O-caffeoyl-β-D-glucopyranoside (4) has been isolated from ethanol extract of the aerial parts of Clematis terniflora DC. On the basis of their spectroscopic and chemical evidence, the new compound was elucidated as (6-O-β-D-glucopyranosyl-1H-indol-3-yl) carboxylic acid methyl ester (1). Compounds 1 and 3 showed significant cytotoxicity against human ECA-109. PMID:24050211

  12. Antioxidant neolignan and phenolic glucosides from the fruit of Euterpe oleracea.

    PubMed

    Hu, Jian; Zhao, Jianping; Khan, Shabana I; Liu, Qiang; Liu, Yang; Ali, Zulfiqar; Li, Xing-Cong; Zhang, Shui-han; Cai, Xiong; Huang, Hui-yong; Wang, Wei; Khan, Ikhlas A

    2014-12-01

    Three new glucosides, namely, (-)-7R8S-7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-O-β-D-glucopyranoside (1), (+)-7S8R-7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-O-β-D-glucopyranoside (2) and 4-hydroxy-2-methoxyphenyl 1-O-[6-(hydrogen 3-hydroxy-3-methylpentanedioate)]-β-D-glucopyranoside (3), along with 6 known compounds were isolated from the fruit of Euterpe oleracea Mart. Their structures were elucidated based on spectroscopic analyses including NMR, HR-ESI-MS and CD. All the isolated compounds demonstrated significant antioxidant activity and 2 displayed moderate cytotoxicity against HL-60 cells. PMID:25284430

  13. Novel Indole-N-glucoside, TA-1887 As a Sodium Glucose Cotransporter 2 Inhibitor for Treatment of Type 2 Diabetes.

    PubMed

    Nomura, Sumihiro; Yamamoto, Yasuo; Matsumura, Yosuke; Ohba, Kiyomi; Sakamaki, Shigeki; Kimata, Hirotaka; Nakayama, Keiko; Kuriyama, Chiaki; Matsushita, Yasuaki; Ueta, Kiichiro; Tsuda-Tsukimoto, Minoru

    2014-01-01

    Inhibition of the renal sodium glucose cotransporter (SGLT) increases urinary glucose excretion (UGE) and thus reduces blood glucose levels during hyperglycemia. To explore the potential of new antihyperglycemic agents, we synthesized and determined the human SGLT2 (hSGLT2) inhibitory potential of novel substituted 3-benzylindole-N-glucosides 6. Optimization of 6 resulted in the discovery of 3-(4-cyclopropylbenzyl)-4-fluoroindole-N-glucoside 6a-4 (TA-1887), a highly potent and selective hSGLT2 inhibitor, with pronounced antihyperglycemic effects in high-fat diet-fed KK (HF-KK) mice. Our results suggest the potential of indole-N-glucosides as novel antihyperglycemic agents through inhibition of renal SGLT2. PMID:24900773

  14. Synthesis of 1,2-cis-2-C-branched aryl-C-glucosides via desulfurization of carbohydrate based hemithioacetals

    PubMed Central

    Mebrahtu, Fanuel M; Manana, Mandlenkosi M; Madumo, Kagiso; Sokamisa, Mokela S

    2015-01-01

    Summary 1-C and 2-C-branched carbohydrates are present as substructures in a number of biologically important compounds. Although the synthesis of such carbohydrate derivatives is extensively studied, the synthesis of 1,2-cis-2-C-branched C-, S-, and N-glycosides is less explored. In this article a synthetic strategy for the synthesis of 1,2-cis-2-C-branched-aryl-C-glucosides is reported via a hydrogenolytic desulfurization of suitably orientated carbohydrate based hemithioacetals. 1,2-cis-2-Hydroxymethyl and 2-carbaldehyde of aryl-C-glucosides have been synthesized using the current strategy in very good yields. The 2-carbaldehyde-aryl-C-glucosides have been identified as suitable substrates for the stereospecific preparation of 2,3-unsaturated-aryl-C-glycosides (Ferrier products). PMID:26124859

  15. In vitro digestion and lactase treatment influence uptake of quercetin and quercetin glucoside by the Caco-2 cell monolayer

    PubMed Central

    Boyer, Jeanelle; Brown, Dan; Liu, Rui Hai

    2005-01-01

    Background Quercetin and quercetin glycosides are widely consumed flavonoids found in many fruits and vegetables. These compounds have a wide range of potential health benefits, and understanding the bioavailability of flavonoids from foods is becoming increasingly important. Methods This study combined an in vitro digestion, a lactase treatment and the Caco-2 cell model to examine quercetin and quercetin glucoside uptake from shallot and apple homogenates. Results The in vitro digestion alone significantly decreased quercetin aglycone recovery from the shallot digestate (p < 0.05), but had no significant effect on quercetin-3-glucoside recovery (p > 0.05). Digestion increased the Caco-2 cell uptake of shallot quercetin-4'-glucoside by 2-fold when compared to the non-digested shallot. Despite the loss of quercetin from the digested shallot, the bioavailability of quercetin aglycone to the Caco-2 cells was the same in both the digested and non-digested shallot. Treatment with lactase increased quercetin recovery from the shallot digestate nearly 10-fold and decreased quercetin-4'-glucoside recovery by more than 100-fold (p < 0.05), but had no effect on quercetin recovery from apple digestates. Lactase treatment also increased shallot quercetin bioavailability to the Caco-2 cells approximately 14-fold, and decreased shallot quercetin-4'-glucoside bioavailability 23-fold (p < 0.05). These Caco-2 cells had lactase activity similar to that expressed by a lactose intolerant human. Conclusions The increase in quercetin uptake following treatment with lactase suggests that dietary supplementation with lactase may increase quercetin bioavailability in lactose intolerant humans. Combining the digestion, the lactase treatment and the Caco-2 cell culture model may provide a reliable in vitro model for examining flavonoid glucoside bioavailability from foods. PMID:15644141

  16. Unambiguous Determination of the Absolute Configuration of Dimeric Stilbene Glucosides from the Rhizomes of Gnetum africanum.

    PubMed

    Buffeteau, Thierry; Cavagnat, Dominique; Bisson, Jonathan; Marchal, Axel; Kapche, Gilbert D; Battistini, Ilaria; Da Costa, Gregory; Badoc, Alain; Monti, Jean-Pierre; Mérillon, Jean-Michel; Waffo-Téguo, Pierre

    2014-08-22

    Dimeric stilbene glucosides 1-3 [two diastereomers of (-)-gnemonoside A (1a and 1b), (-)-gnemonoside C (2), and (-)-gnemonoside D (3)] as well as a mixture of the two enantiomers of gnetin C (4) were isolated from the rhizomes of Gnetum africanum. The two enantiomers of gnetin C, (+)-4 and (-)-4, were obtained from the aglycones of 1a and 1b, respectively. The configurations of these stilbenoids were investigated by NMR and vibrational circular dichroism (VCD) experiments. The absolute configurations of (-)-1a, (-)-2, (-)-3, and (-)-4 were established as 7aS,8aS by VCD spectroscopy in combination with density functional theory calculations. The antiamyloidogenic activity of the isolated stilbenes was also evaluated versus beta-amyloid fibrils. The four glucosides of gnetin C (1a, 1b, 2, and 3) were found to be the most active compounds, with inhibition percentages of 56, 56, 58, and 54 at 10 μM, respectively. PMID:25093453

  17. Enhanced production of β-glucosides by in-situ UDP-glucose regeneration.

    PubMed

    Huang, Fong-Chin; Hinkelmann, Jens; Hermenau, Alexandra; Schwab, Wilfried

    2016-04-20

    Glycosyltransferase (GT)-mediated methodology is recognized as one of the most practical approaches for large-scale production of glycosides. However, GT enzymes require a sugar nucleotide as donor substrate that must be generated in situ for preparative applications by recycling of the nucleotide moiety, e.g. by sucrose synthase (SUS). Three plant GT genes CaUGT2, VvGT14a, and VvGT15c and the fungal SbUGTA1 were successfully co-expressed with GmSUS from soybean in Escherichia coli BL21 and W cells. In vitro, the crude protein extracts prepared from four GT genes and GmSUS co-expressing cells were able to convert several small molecules to the corresponding glucosides, when sucrose and UDP were supplied. In addition, GmSUS was able to enhance the glucosylation efficiency and reduced the amount of supplying UDP-glucose. In the biotransformation system, co-expression of VvGT15c with GmSUS also improved the glucosylation of geraniol and enhanced the resistance of the cells against the toxic terpenol. GT-EcW and GTSUS-EcW cells tolerated up to 2mM geraniol and converted more than 99% of the substrate into the glucoside at production rates exceeding 40μgml(-1)h(-1). The results confirm that co-expression of SUS allows in situ regeneration of UDP-sugars and avoids product inhibition by UDP. PMID:26912290

  18. Effects on Liver Lipid Metabolism of the Naturally Occurring Dietary Flavone Luteolin-7-glucoside.

    PubMed

    Sá, Carla; Oliveira, Ana Rita; Machado, Cátia; Azevedo, Marisa; Pereira-Wilson, Cristina

    2015-01-01

    Disruptions in whole-body lipid metabolism can lead to the onset of several pathologies such as nonalcoholic fatty liver disease (NAFLD) and cardiovascular diseases (CVDs). The present study aimed at elucidating the molecular mechanisms behind the lipid-lowering effects of the flavone luteolin-7-glucoside (L7G) which we previously showed to improve plasma lipid profile in rats. L7G is abundant in plant foods of Mediterranean diet such as aromatic plants used as herbs. Results show that dietary supplementation with L7G for one week induced the expression of peroxisome proliferator-activated receptor-alpha (PPAR-α) and of its target gene carnitine palmitoyl transferase 1 (CPT-1) in rat liver. L7G showed a tendency to decrease the hepatic expression of sterol regulatory element-binding protein-1 (SREBP-1), without affecting fatty acid synthase (FAS) protein levels. Although SREBP-2 and LDLr mRNA levels did not change, the expression of HMG CoA reductase (HMGCR) was significantly repressed by L7G. L7G also inhibited this enzyme's in vitro activity in a dose dependent manner, but only at high and not physiologically relevant concentrations. These results add new evidence that the flavone luteolin-7-glucoside may help in preventing metabolic diseases and clarify the mechanisms underlying the beneficial health effects of diets rich in fruits and vegetables. PMID:26113868

  19. Development and Evaluation of Monoclonal Antibodies for the Glucoside of T-2 Toxin (T2-Glc)

    PubMed Central

    Maragos, Chris M.; Kurtzman, Cletus; Busman, Mark; Price, Neil; McCormick, Susan

    2013-01-01

    The interactions between fungi and plants can yield metabolites that are toxic in animal systems. Certain fungi are known to produce sesquiterpenoid trichothecenes, such as T-2 toxin, that are biotransformed by several mechanisms including glucosylation. The glucosylated forms have been found in grain and are of interest as potential reservoirs of T-2 toxin that are not detected by many analytical methods. Hence the glucosides of trichothecenes are often termed “masked” mycotoxins. The glucoside of T-2 toxin (T2-Glc) was linked to keyhole limpet hemocyanin and used to produce antibodies in mice. Ten monoclonal antibody (Mab)-producing hybridoma cell lines were developed. The Mabs were used in immunoassays to detect T2-Glc and T-2 toxin, with midpoints of inhibition curves (IC50s) in the low ng/mL range. Most of the Mabs demonstrated good cross-reactivity to T-2 toxin, with lower recognition of HT-2 toxin. One of the clones (2-13) was further characterized with in-depth cross-reactivity and solvent tolerance studies. Results suggest Mab 2-13 will be useful for the simultaneous detection of T-2 toxin and T2-Glc. PMID:23877196

  20. Evolution of aromatic β-glucoside utilization by successive mutational steps in Escherichia coli.

    PubMed

    Zangoui, Parisa; Vashishtha, Kartika; Mahadevan, Subramony

    2015-02-15

    The bglA gene of Escherichia coli encodes phospho-β-glucosidase A capable of hydrolyzing the plant-derived aromatic β-glucoside arbutin. We report that the sequential accumulation of mutations in bglA can confer the ability to hydrolyze the related aromatic β-glucosides esculin and salicin in two steps. In the first step, esculin hydrolysis is achieved through the acquisition of a four-nucleotide insertion within the promoter of the bglA gene, resulting in enhanced steady-state levels of the bglA transcript. In the second step, hydrolysis of salicin is achieved through the acquisition of a point mutation within the bglA structural gene close to the active site without the loss of the original catabolic activity against arbutin. These studies underscore the ability of microorganisms to evolve additional metabolic capabilities by mutational modification of preexisting genetic systems under selection pressure, thereby expanding their repertoire of utilizable substrates. PMID:25448815

  1. Engineering of glucoside acceptors for the regioselective synthesis of beta-(1-->3)-disaccharides with glycosynthases.

    PubMed

    Marton, Zsuzanna; Tran, Vinh; Tellier, Charles; Dion, Michel; Drone, Jullien; Rabiller, Claude

    2008-11-24

    Glycosynthase mutants obtained from Thermotogamaritima were able to catalyze the regioselective synthesis of aryl beta-D-Galp-(1-->3)-beta-D-Glcp and aryl beta-D-Glcp-(1-->3)-beta-D-Glcp in high yields (up to 90 %) using aryl beta-D-glucosides as acceptors. The need for an aglyconic aryl group was rationalized by molecular modeling calculations, which have emphasized a high stabilizing interaction of this group by stacking with W312 of the enzyme. Unfortunately, the deprotection of the aromatic group of the disaccharides was not possible without partial hydrolysis of the glycosidic bond. The replacement of aryl groups by benzyl ones could offer the opportunity to deprotect the anomeric position under very mild conditions. Assuming that benzyl acceptors could preserve the stabilizing stacking, benzyl beta-d-glucoside firstly assayed as acceptor resulted in both poor yields and poor regioselectivity. Thus, we decided to undertake molecular modeling calculations in order to design which suitable substituted benzyl acceptors could be used. This study resulted in the choice of 2-biphenylmethyl beta-D-glucopyranoside. This choice was validated experimentally, since the corresponding beta-(1-->3) disaccharide was obtained in good yields and with a high regioselectivity. At the same time, we have shown that phenyl 1-thio-beta-D-glucopyranoside was also an excellent substrate leading to similar results as those obtained with the O-phenyl analogue. The NBS deprotection of the S-phenyl group afforded the corresponding disaccharide quantitatively. PMID:18828996

  2. Novel quercetin-3-O-glucoside eicosapentaenoic acid ester ameliorates inflammation and hyperlipidemia.

    PubMed

    Sekhon-Loodu, Satvir; Ziaullah, Ziaullah; Rupasinghe, H P Vasantha; Wang, Yanwen; Kulka, Marianna; Shahidi, Fereidoon

    2015-08-01

    Quercetin, a major flavonol, present abundantly in apples and onions, is widely studied for ameliorating metabolic syndrome abnormalities. However, quercetin is mainly present in plant food in the form of quercetin glycosides and has been reported for poor gastrointestinal absorption. The present study was designed with the purpose of imparting a lipophilic property to quercetin-3-O-glucoside (QG) by its acylation with eicosapentaenoic acid (EPA) and to study the influence of eicosapentaenoic acid ester of quercetin-3-O-glucoside (QE) on hyperlipidemia and inflammation in vivo and in vitro. QE was more effective in reducing the production of tumor necrosis factor-alpha (TNF-α), prostaglandin 2 (PGE2), cyclo-oxygenase (COX)-2 levels and nuclear expression of nuclear factor-kappa B (NF-кB) compared to the parent compounds (QG and EPA) and commercial drugs, after lipopolysaccharides (LPS) induced inflammation in THP-1 derived macrophages. Serum high-density lipoprotein (HDL)-cholesterol was significantly higher and hepatic total cholesterol concentration was lower in the rats fed high-fat diet supplemented with QE, compared to the high-fat diet with inflammation (HFL). The serum concentrations of C-reactive protein (CRP), interleukin (IL)-6, and interferon-gamma (IFN-γ) were significantly lower in QE treatment group than HFL group. EPA conjugated flavonol, QE, had significant anti-inflammatory and hypolipidemic properties and may be effective for the treatment of obesity-related disorders. PMID:26165697

  3. Isoarnottinin 4'-glucoside, a glycosylated coumarin from Prangos uloptera, with biological activity.

    PubMed

    Razavi, Seyed Mehdi; Zarrini, Gholamreza; Rad, Farah Gholami

    2011-01-01

    Coumarins are a well-known group of natural products distributed in the plant kingdom especially in the family Apiaceae with various biological activities. Isoarnottinin 4'-glucoside is a simple glycosylated coumarin found previously in a few genera of Apiaceae, and its biological activities have not been previously described in details. In the present paper, the compound was isolated from Prangos uloptera (Apiaceae) leaves using HPLC techniques. Antimicrobial, phytotoxic and cytotoxic activities of the compound were evaluated by disk diffusion, lettuce assay and MTT method. Our results indicated that the compound has high antibacterial effect against Erwinia carotovora, a common plant pathogen with MIC value of 100 microg/mL. The compound also exhibited significant phytotoxic activity against lettuce and modest cytotoxic activity against HeLa cell line with IC50 of 0 .84 mg/mL. It could be concluded that isoamottinin 4'-glucoside may play phytoalexin or allelopathic role for plant and may be a candidate for an antibacterial agent or a bioherbicide. PMID:21717896

  4. Indoline Amide Glucosides from Portulaca oleracea: Isolation, Structure, and DPPH Radical Scavenging Activity.

    PubMed

    Jiao, Ze-Zhao; Yue, Su; Sun, Hong-Xiang; Jin, Tian-Yun; Wang, Hai-Na; Zhu, Rong-Xiu; Xiang, Lan

    2015-11-25

    A polyamide column chromatography method using an aqueous ammonia mobile phase was developed for large-scale accumulation of water-soluble indoline amide glucosides from a medicinal plant, Portulaca oleracea. Ten new [oleraceins H, I, K, L, N, O, P, Q, R, S (1-10)] and four known [oleraceins A-D (11-14)] indoline amide glucosides were further purified and structurally characterized by various chromatographic and spectroscopic methods. The DPPH radical scavenging activities of oleraceins K (5) and L (6), with EC50 values of 15.30 and 16.13 μM, respectively, were twice that of a natural antioxidant, vitamin C; the EC50 values of the 12 other indoline amides, which ranged from 29.05 to 43.52 μM, were similar to that of vitamin C. Structure-activity relationships indicated that the DPPH radical scavenging activities of these indoline amides correlate with the numbers and positions of the phenolic hydroxy groups. PMID:26562741

  5. Effects on Liver Lipid Metabolism of the Naturally Occurring Dietary Flavone Luteolin-7-glucoside

    PubMed Central

    Sá, Carla; Oliveira, Ana Rita; Machado, Cátia; Azevedo, Marisa; Pereira-Wilson, Cristina

    2015-01-01

    Disruptions in whole-body lipid metabolism can lead to the onset of several pathologies such as nonalcoholic fatty liver disease (NAFLD) and cardiovascular diseases (CVDs). The present study aimed at elucidating the molecular mechanisms behind the lipid-lowering effects of the flavone luteolin-7-glucoside (L7G) which we previously showed to improve plasma lipid profile in rats. L7G is abundant in plant foods of Mediterranean diet such as aromatic plants used as herbs. Results show that dietary supplementation with L7G for one week induced the expression of peroxisome proliferator-activated receptor-alpha (PPAR-α) and of its target gene carnitine palmitoyl transferase 1 (CPT-1) in rat liver. L7G showed a tendency to decrease the hepatic expression of sterol regulatory element-binding protein-1 (SREBP-1), without affecting fatty acid synthase (FAS) protein levels. Although SREBP-2 and LDLr mRNA levels did not change, the expression of HMG CoA reductase (HMGCR) was significantly repressed by L7G. L7G also inhibited this enzyme's in vitro activity in a dose dependent manner, but only at high and not physiologically relevant concentrations. These results add new evidence that the flavone luteolin-7-glucoside may help in preventing metabolic diseases and clarify the mechanisms underlying the beneficial health effects of diets rich in fruits and vegetables. PMID:26113868

  6. A UDP-glucosyltransferase functions in both acylphloroglucinol glucoside and anthocyanin biosynthesis in strawberry (Fragaria × ananassa).

    PubMed

    Song, Chuankui; Zhao, Shuai; Hong, Xiaotong; Liu, Jingyi; Schulenburg, Katja; Schwab, Wilfried

    2016-03-01

    Physiologically active acylphloroglucinol (APG) glucosides were recently found in strawberry (Fragaria sp.) fruit. Although the formation of the APG aglycones has been clarified, little is known about APG glycosylation in plants. In this study we functionally characterized ripening-related glucosyltransferase genes in Fragaria by comprehensive biochemical analyses of the encoded proteins and by a RNA interference (RNAi) approach in vivo. The allelic proteins UGT71K3a/b catalyzed the glucosylation of diverse hydroxycoumarins, naphthols and flavonoids as well as phloroglucinols, enzymatically synthesized APG aglycones and pelargonidin. Total enzymatic synthesis of APG glucosides was achieved by co-incubation of recombinant dual functional chalcone/valerophenone synthase and UGT71K3 proteins with essential coenzyme A esters and UDP-glucose. An APG glucoside was identified in strawberry fruit which has not yet been reported in other plants. Suppression of UGT71K3 activity in transient RNAi-silenced fruits led to a loss of pigmentation and a substantial decrease of the levels of various APG glucosides and an anthocyanin. Metabolite analyses of transgenic fruits confirmed UGT71K3 as a UDP-glucose:APG glucosyltransferase in planta. These results provide the foundation for the breeding of fruits with improved health benefits and for the biotechnological production of bioactive natural products. PMID:26859691

  7. Clarification of Reconstituted Frozen Orange Juice Concentrate by Continuous Flow Centrifugation for Limonin Glucoside Solid Phase Extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The clarification of reconstituted frozen orange juice concentrate by continuous-flow centrifugation in preparation to being applied to a solid phase extraction column for the isolation of limonin glucoside has been evaluated. Clarification experiments spanning over three different flow rates (325,...

  8. A family 3 glycosyl hydrolase of Dickeya dadantii 3937 is involved in the cleavage of aromatic glucosides.

    PubMed

    Charaoui-Boukerzaza, Sana; Hugouvieux-Cotte-Pattat, Nicole

    2013-11-01

    Dickeya dadantii is a phytopathogenic bacterium secreting a large array of plant-cell-wall-degrading enzymes that participate in the infection and maceration of the host plant tissue. Sequencing of the D. dadantii 3937 genome predicted several genes encoding potential glycosidases. One of these genes, bgxA, encodes a protein classified in family 3 of glycosyl hydrolases. Inactivation of bgxA and the use of a gene fusion revealed that this gene is not essential for D. dadantii pathogenicity but that it is expressed during plant infection. The bgxA expression is induced in the presence of glycosidic or non-glycosidic aromatic compounds, notably ferulic acid, cinnamic acid, vanillic acid and salicin. The BgxA enzyme has a principal β-d-glucopyranosidase activity and a secondary β-d-xylopyranosidase activity (ratio 70 : 1). This enzyme activity is inhibited by different aromatic glycosides or phenolic compounds, in particular salicin, arbutin, ferulic acid and vanillic acid. Together, the induction effects and the enzyme inhibition suggest that BgxA is mostly involved in the cleavage of aromatic β-glucosides. There is evidence of functional redundancy in the D. dadantii β-glucoside assimilation pathway. In contrast to other β-glucoside assimilation systems, involving cytoplasmic phospho-β-glucosidases, the cleavage of aromatic glucosides in the periplasmic space by BgxA may avoid the release of a toxic phenolic aglycone into the cytoplasm while still allowing for catabolism of the glucose moiety. PMID:24002750

  9. Synthesis and biological evaluation of novel dioxa-bicycle C-aryl glucosides as SGLT2 inhibitors.

    PubMed

    Yan, Qi; Ding, Ning; Li, Yingxia

    2016-02-01

    A series of novel C-aryl glucosides containing dioxa-bicycle were synthesized and evaluated for inhibition activity against hSGLT2. Among the compounds tested, compound 6a showed moderate SGLT2 inhibition activities at 700 nM. The results could benefit the discovery of new SGLT2 inhibitors. PMID:26735747

  10. Flavonoid C-glucosides Derived from Flax Straw Extracts Reduce Human Breast Cancer Cell Growth In vitro and Induce Apoptosis

    PubMed Central

    Czemplik, Magdalena; Mierziak, Justyna; Szopa, Jan; Kulma, Anna

    2016-01-01

    Flax straw of flax varieties that are grown for oil production is a by product which represents a considerable biomass source. Therefore, its potential application for human use is of high interest. Our research has revealed that flax straw is rich in flavonoid C-glucosides, including vitexin, orientin, and isoorientin. The objective of this study was to evaluate the cytotoxicity and possible proapoptotic effect of flax straw derived C-glucosides of flavonoids in the human breast adenocarcinoma cell line (MCF-7). The effects of flax straw derived flavonoid C-glucosides on cell proliferation of MCF-7 cells were evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and sulforhodamine B assays. The expression of apoptosis-related genes was assessed by real-time PCR. Our data revealed that flax C-glucosides as well as pure compounds are cytotoxic toward MCF-7 cells and inhibit their proliferation. Moreover, the induction of apoptosis was correlated with the changes in the mRNA level of pro-apoptotic genes. Increased expression of bax and caspase-7, -8, and -9 and decreased mRNA expression of bcl-2 was observed, whereas the mRNA levels of p53 and mdm2 were not altered. These results clearly demonstrated that flax straw metabolites effectively induced growth inhibition and apoptosis in human breast adenocarcinoma cells.

  11. In vitro anti-HIV-1 activities of kaempferol and kaempferol-7-O-glucoside isolated from Securigera securidaca

    PubMed Central

    Behbahani, M.; Sayedipour, S.; Pourazar, A.; Shanehsazzadeh, M.

    2014-01-01

    Previously, we reported that the kaempferol and kaempferol-7-O-glucoside isolated from Securigera securidaca showed potent anti-HSV activity. In the present study the anti-HIV-1 activities of kaempferol and kaempferol-7-O-glucoside are investigated at different concentrations (100, 50, 25 and 10 μg/ml) using HIV-1 p24 Antigen kit. Real-time Polymerase chain reaction (RT-PCR) assay was also used for quantification of full range of virus load observed in treated and untreated cells. According to the results of RT- PCR, tested compounds at a concentration of 100 μg/ml exerted potent inhibitory effect. Time of drug addition experiments demonstrated that these compounds exerted their inhibitory effects on the early stage of HIV infection. The results also showed potent anti-HIV-1 reverse transcriptase activity. Antiviral activity of kaempferol-7-O-glucoside was more pronounced than that of kaempferol. These findings demonstrate that kaempferol-7-O-glucoside could be considered as a new potential drug candidate for the treatment of HIV infection which requires further assessments. PMID:26339261

  12. In vitro anti-HIV-1 activities of kaempferol and kaempferol-7-O-glucoside isolated from Securigera securidaca.

    PubMed

    Behbahani, M; Sayedipour, S; Pourazar, A; Shanehsazzadeh, M

    2014-01-01

    Previously, we reported that the kaempferol and kaempferol-7-O-glucoside isolated from Securigera securidaca showed potent anti-HSV activity. In the present study the anti-HIV-1 activities of kaempferol and kaempferol-7-O-glucoside are investigated at different concentrations (100, 50, 25 and 10 μg/ml) using HIV-1 p24 Antigen kit. Real-time Polymerase chain reaction (RT-PCR) assay was also used for quantification of full range of virus load observed in treated and untreated cells. According to the results of RT- PCR, tested compounds at a concentration of 100 μg/ml exerted potent inhibitory effect. Time of drug addition experiments demonstrated that these compounds exerted their inhibitory effects on the early stage of HIV infection. The results also showed potent anti-HIV-1 reverse transcriptase activity. Antiviral activity of kaempferol-7-O-glucoside was more pronounced than that of kaempferol. These findings demonstrate that kaempferol-7-O-glucoside could be considered as a new potential drug candidate for the treatment of HIV infection which requires further assessments. PMID:26339261

  13. Protective effects of cyanidin-3-O-glucoside from blackberry extract against peroxynitrite-induced endothelial dysfunction and vascular failure.

    PubMed

    Serraino, Ivana; Dugo, Laura; Dugo, Paola; Mondello, Luigi; Mazzon, Emanuela; Dugo, Giovanni; Caputi, Achille Patrizio; Cuzzocrea, Salvatore

    2003-07-18

    Anthocyanins are a group of naturally occurring phenolic compounds as colorants in several plants, flowers and fruits. These pigments have a great importance as quality indicators, as chemotaxonomic markers and antioxidants. The content of blackberry (Rubus species) juice was investigated by HPLC/ESI/MS using narrow bore HPLC columns. Using this method we demonstrated that cyanidin-3-O-glucoside represents about 80% of the total anthocyanin contents in blackberry extract. Here we investigated antioxidant activity of the blackberry juice and cyanidin-3-O-glucoside on the endothelial dysfunction in cells and in vascular rings exposed to peroxynitrite. In human umbilical vein endothelial cells (HUVEC) in vitro, peroxynitrite caused a significant suppression of mitochondrial respiration (38 +/- 2.1% of control cells), as measured by the mitochondrial-dependent conversion of the dye MTT to formazan. Peroxynitrite caused DNA strand breakage (63 +/- 1.9% single strand vs 3 +/- 0.9% single strand in control cells), as measured by the alkaline unwinding assay, and caused an activation of PARS, as measured by the incorporation of radiolabeled NAD(+) to nuclear proteins. Blackberry juice (different dilutions that contained 80 ppm;40 ppm;14.5 ppm of cyanidin-3-O-glucoside) and cyanidin-3-O-glucoside (as chloride) (0.085 microM; 0.028 microM; 0.0085 microM) reduced the peroxynitrite-induced suppression of mitochondrial respiration, DNA damage and PARS activation in HUVECs. Vascular rings exposed to peroxynitrite exhibited reduced endothelium-dependent relaxant responses in response to acetylcholine as well as a vascular contractility dysfunction in response to norepinephrine. The development of this peroxynitrite-induced vascular dysfunction was ameliorated by the blackberry juice (different dilutions that contained 80 ppm;40 ppm;14.5 ppm of cyanidin-3-O-glucoside) and cyanidin-3-O-glucoside (as chloride) (0.085 microM;0.028 microM;0.0085 microM). In conclusion our findings

  14. Helicobacter pylori Cholesteryl α-Glucosides Contribute to Its Pathogenicity and Immune Response by Natural Killer T Cells

    PubMed Central

    Ito, Yuki; Vela, Jose Luis; Matsumura, Fumiko; Hoshino, Hitomi; Tyznik, Aaron; Lee, Heeseob; Girardi, Enrico; Zajonc, Dirk M.; Liddington, Robert; Kobayashi, Motohiro; Bao, Xingfeng; Bugaytsova, Jeanna; Borén, Thomas; Jin, Rongsheng; Zong, Yinong; Seeberger, Peter H.; Nakayama, Jun; Kronenberg, Mitchell; Fukuda, Minoru

    2013-01-01

    Approximately 10–15% of individuals infected with Helicobacter pylori will develop ulcer disease (gastric or duodenal ulcer), while most people infected with H. pylori will be asymptomatic. The majority of infected individuals remain asymptomatic partly due to the inhibition of synthesis of cholesteryl α-glucosides in H. pylori cell wall by α1,4-GlcNAc-capped mucin O-glycans, which are expressed in the deeper portion of gastric mucosa. However, it has not been determined how cholesteryl α-glucosyltransferase (αCgT), which forms cholesteryl α-glucosides, functions in the pathogenesis of H. pylori infection. Here, we show that the activity of αCgT from H. pylori clinical isolates is highly correlated with the degree of gastric atrophy. We investigated the role of cholesteryl α-glucosides in various aspects of the immune response. Phagocytosis and activation of dendritic cells were observed at similar degrees in the presence of wild-type H. pylori or variants harboring mutant forms of αCgT showing a range of enzymatic activity. However, cholesteryl α-glucosides were recognized by invariant natural killer T (iNKT) cells, eliciting an immune response in vitro and in vivo. Following inoculation of H. pylori harboring highly active αCgT into iNKT cell-deficient (Jα18−/−) or wild-type mice, bacterial recovery significantly increased in Jα18−/− compared to wild-type mice. Moreover, cytokine production characteristic of Th1 and Th2 cells dramatically decreased in Jα18−/− compared to wild-type mice. These findings demonstrate that cholesteryl α-glucosides play critical roles in H. pylori-mediated gastric inflammation and precancerous atrophic gastritis. PMID:24312443

  15. Potential applications of glucosyltransferases in terpene glucoside production: impacts on the use of aroma and fragrance.

    PubMed

    Schwab, Wilfried; Fischer, Thilo C; Giri, Ashok; Wüst, Matthias

    2015-01-01

    The detection of glucoconjugated forms of monoterpene alcohols in rose petals in the late 1960s opened the new field of nonvolatile aroma precursors in flavor research. It is now well established that odorless glycosides represent a significant pool of aroma precursors in plants where they act as preformed but inactivated defense or attractive chemicals. Technical improvements in the separation and identification of plant secondary metabolites have provided a multitude of chemical structures, but functional characterization of glycosyltransferases that catalyze their formation lags behind. As technical efforts and costs for DNA sequencing dramatically dropped during the last decade, the number of plant genome sequences increased significantly, thus providing opportunities to functionally characterize the glycosyltransferase gene families in plants. These studies yielded the first glycosyltransferase genes that encode efficient biocatalysts for the production of monoterpene glucosides. They have applications in the food, feed, chemical, cosmetic, and pharmaceutical industries as slow release aroma chemicals. PMID:25431013

  16. Mozambioside Is an Arabica-Specific Bitter-Tasting Furokaurane Glucoside in Coffee Beans.

    PubMed

    Lang, Roman; Klade, Stefan; Beusch, Anja; Dunkel, Andreas; Hofmann, Thomas

    2015-12-01

    Sensory-guided fractionation of a roasted coffee beverage revealed a highly polar, bitter-tasting subfraction, from which the furokaurane glucoside mozambioside was isolated and identified in its chemical structure by means of HDMS and NMR spectra. Sensory evaluation revealed a bitter taste recognition threshold of 60 (± 10) μmol/L. UPLC-HDMS quantitation of raw coffee beans showed that Arabica coffees contained 396-1188 nmol/g mozambioside, whereas only traces (<5 nmol/g) were detected in Robusta coffees, thus suggesting that mozambioside can be used as an analytical marker for Arabica coffee. Roasted Arabica contained a substantially reduced concentration (232 ± 37 nmol/g), indicating partial degradation of mozambioside during coffee roasting. Mozambioside was nearly quantitatively extracted into the aqueous brew during coffee-making (86-98%). PMID:26585544

  17. Polycyclic polyprenylated acylphloroglucinols and chromone O-glucosides from Hypericum henryi subsp. uraloides.

    PubMed

    Chen, Xuan-Qin; Li, Yan; Cheng, Xiao; Wang, Kou; He, Juan; Pan, Zheng-Hong; Li, Ming-Ming; Peng, Li-Yan; Xu, Gang; Zhao, Qin-Shi

    2010-01-01

    Two new C(30)-epimeric polycyclic polyprenylated acylphloroglucinols (PPAPs), named uralodins B and C (1 and 2, resp.), were isolated from the aerial parts of Hypericum henryi subsp. uraloides together with two new chromone glucosides, urachromones A and B (3 and 4, resp.), as well as 16 known compounds. Their structures were established by extensive NMR techniques and MS analysis. The epimers 1 and 2 always behaved like a single compound when examined by TLC, and were separated by HPLC. Their configuration was distinguished by comparative analysis of the NMR data with known analogues together with the ROESY experiment. All the isolated PPAPs were evaluated for their cytotoxic activities against HepG2, SGC7901, HL-60, and K562 cell lines. Compound 1 showed modest cytotoxic activities against SGC7901 and HL-60 cell lines, and 2 showed modest cytotoxic activities against HepG2, SGC7901, HL-60, and K562 cell lines. PMID:20087990

  18. Three spirostanol saponins and a flavane-O-glucoside from the fresh rhizomes of Tupistra chinensis.

    PubMed

    Xiao, Yan-Hua; Yin, Hai-Long; Chen, Li; Tian, Yin; Liu, Shi-Jun; Zhang, Guang-Jie; Chen, Heng-Wen; Jin, Hong; Li, Bin; Dong, Jun-Xing

    2015-04-01

    Four new compounds, including three new spirostanol saponins [tupistroside G-I (1-3)] and a new flavane-O-glucoside [tupichiside A (4)], together with ten known compounds, were isolated from the fresh rhizomes of Tupistra chinensis. The structures of the new compounds were elucidated by spectroscopic analysis and chemical evidence. All compounds were tested in vitro for their cytotoxic activities against the Human LoVo and BGC-823 cell lines, and six of them were found to possess potent cytotoxicity. Compounds 2, 8 and 9 showed significant cytotoxicity against the tested tumor cell lines with IC50 values ranging from 0.2 to 0.9μM. PMID:25707589

  19. Decyl glucoside as a corrosion inhibitor for magnesium-air battery

    NASA Astrophysics Data System (ADS)

    Deyab, M. A.

    2016-09-01

    In this research, the effects of decyl glucoside (DG) on the corrosion inhibition and battery performance of Mg-air battery have been investigated. Chemical and electrochemical techniques have been used to evaluate the corrosion rate and inhibitor efficiency. Mg surface has been characterized with scanning electron microscopy (SEM) and infrared spectroscopy (FTIR). A significant reduction in the corrosion rate of Mg in battery electrolyte (3.5% NaCl solution) has been observed in the presence of DG surfactant. Maximum inhibition efficiency (>94%) is achieved at critical micelle concentration of DG surfactant (CMC = 2.5 mM). The presence of DG surfactant increases the activation energy of the corrosion reaction. Physisorption mechanism has been suggested for the inhibition action of DG surfactant. The Mg-air battery containing DG surfactant offers higher operating voltage, discharge capacity and anodic utilization than in its absence.

  20. Occurrence of Deoxynivalenol and Deoxynivalenol-3-glucoside in Hard Red Spring Wheat Grown in the USA

    PubMed Central

    Simsek, Senay; Ovando-Martínez, Maribel; Ozsisli, Bahri; Whitney, Kristin; Ohm, Jae-Bom

    2013-01-01

    Deoxynivalenol (DON) is a mycotoxin found in wheat that is infected with Fusarium fungus. DON may also be converted to a type of “masked mycotoxin”, named deoxynivalenol-3-glucoside (D3G), as a result of detoxification of the plant. In this study, DON and D3G were measured using gas chromatographic (GC) and liquid chromatography-mass spectrometry (LC-MS) in wheat samples collected during 2011 and 2012 in the USA. Results indicate that the growing region had a significant effect on the DON and D3G (p < 0.0001). There was a positive correlation between both methods (GC and LC-MS) used for determination of DON content. DON showed a significant and positive correlation with D3G during 2011. Overall, DON production had an effect on D3G content and kernel damage, and was dependent on environmental conditions during Fusarium infection. PMID:24351720

  1. Stability studies of ascorbic acid 2-glucoside in cosmetic lotion using surface response methodology.

    PubMed

    Huang, Wen-Ying; Lee, Pei-Chi; Huang, Ling-Kuei; Lu, Li-Ping; Liao, Wayne C

    2013-03-15

    Ascorbic acid 2-glucoside (AA-2G) has been widely used in cream and lotion types of cosmetic products. Thus, the degradation of AA-2G caused by the temperature change and pH variation was very critical for determining the bio-functionality of cosmetics. Response surface methodology (RSM) was introduced to study the influence of temperature and pH on the stability of AA-2G. The optimal condition of retaining AA-2G with the highest stability was determined to be 55.3°C and pH 6.4. The antioxidative activities of AA-2G including DPPH and ABTS free radical scavenging activities, metal chelating activity, and reducing ability were also determined. AA-2G was a good ascorbic acid derivative which could be used in cosmetic products as an active ingredient. PMID:23416010

  2. Molecular cloning and characterization of genistein 4'-O-glucoside specific glycosyltransferase from Bacopa monniera.

    PubMed

    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. PMID:24664316

  3. Fusion of Ferredoxin and Cytochrome P450 Enables Direct Light-Driven Biosynthesis.

    PubMed

    Mellor, Silas Busck; Nielsen, Agnieszka Zygadlo; Burow, Meike; Motawia, Mohammed Saddik; Jakubauskas, Dainius; Møller, Birger Lindberg; Jensen, Poul Erik

    2016-07-15

    Cytochrome P450s (P450s) are key enzymes in the synthesis of bioactive natural products in plants. Efforts to harness these enzymes for in vitro and whole-cell production of natural products have been hampered by difficulties in expressing them heterologously in their active form, and their requirement for NADPH as a source of reducing power. We recently demonstrated targeting and insertion of plant P450s into the photosynthetic membrane and photosynthesis-driven, NADPH-independent P450 catalytic activity mediated by the electron carrier protein ferredoxin. Here, we report the fusion of ferredoxin with P450 CYP79A1 from the model plant Sorghum bicolor, which catalyzes the initial step in the pathway leading to biosynthesis of the cyanogenic glucoside dhurrin. Fusion with ferredoxin allows CYP79A1 to obtain electrons for catalysis by interacting directly with photosystem I. Furthermore, electrons captured by the fused ferredoxin moiety are directed more effectively toward P450 catalytic activity, making the fusion better able to compete with endogenous electron sinks coupled to metabolic pathways. The P450-ferredoxin fusion enzyme obtains reducing power solely from its fused ferredoxin and outperforms unfused CYP79A1 in vivo. This demonstrates greatly enhanced electron transfer from photosystem I to CYP79A1 as a consequence of the fusion. The fusion strategy reported here therefore forms the basis for enhanced partitioning of photosynthetic reducing power toward P450-dependent biosynthesis of important natural products. PMID:27119279

  4. Fusion of Ferredoxin and Cytochrome P450 Enables Direct Light-Driven Biosynthesis

    PubMed Central

    2016-01-01

    Cytochrome P450s (P450s) are key enzymes in the synthesis of bioactive natural products in plants. Efforts to harness these enzymes for in vitro and whole-cell production of natural products have been hampered by difficulties in expressing them heterologously in their active form, and their requirement for NADPH as a source of reducing power. We recently demonstrated targeting and insertion of plant P450s into the photosynthetic membrane and photosynthesis-driven, NADPH-independent P450 catalytic activity mediated by the electron carrier protein ferredoxin. Here, we report the fusion of ferredoxin with P450 CYP79A1 from the model plant Sorghum bicolor, which catalyzes the initial step in the pathway leading to biosynthesis of the cyanogenic glucoside dhurrin. Fusion with ferredoxin allows CYP79A1 to obtain electrons for catalysis by interacting directly with photosystem I. Furthermore, electrons captured by the fused ferredoxin moiety are directed more effectively toward P450 catalytic activity, making the fusion better able to compete with endogenous electron sinks coupled to metabolic pathways. The P450-ferredoxin fusion enzyme obtains reducing power solely from its fused ferredoxin and outperforms unfused CYP79A1 in vivo. This demonstrates greatly enhanced electron transfer from photosystem I to CYP79A1 as a consequence of the fusion. The fusion strategy reported here therefore forms the basis for enhanced partitioning of photosynthetic reducing power toward P450-dependent biosynthesis of important natural products. PMID:27119279

  5. Isolation of high-salinity-tolerant bacterial strains, Enterobacter sp., Serratia sp., Yersinia sp., for nitrification and aerobic denitrification under cyanogenic conditions.

    PubMed

    Mpongwana, N; Ntwampe, S K O; Mekuto, L; Akinpelu, E A; Dyantyi, S; Mpentshu, Y

    2016-01-01

    Cyanides (CN(-)) and soluble salts could potentially inhibit biological processes in wastewater treatment plants (WWTPs), such as nitrification and denitrification. Cyanide in wastewater can alter metabolic functions of microbial populations in WWTPs, thus significantly inhibiting nitrifier and denitrifier metabolic processes, rendering the water treatment processes ineffective. In this study, bacterial isolates that are tolerant to high salinity conditions, which are capable of nitrification and aerobic denitrification under cyanogenic conditions, were isolated from a poultry slaughterhouse effluent. Three of the bacterial isolates were found to be able to oxidise NH(4)-N in the presence of 65.91 mg/L of free cyanide (CN(-)) under saline conditions, i.e. 4.5% (w/v) NaCl. The isolates I, H and G, were identified as Enterobacter sp., Yersinia sp. and Serratia sp., respectively. Results showed that 81% (I), 71% (G) and 75% (H) of 400 mg/L NH(4)-N was biodegraded (nitrification) within 72 h, with the rates of biodegradation being suitably described by first order reactions, with rate constants being: 4.19 h(-1) (I), 4.21 h(-1) (H) and 3.79 h(-1) (G), respectively, with correlation coefficients ranging between 0.82 and 0.89. Chemical oxygen demand (COD) removal rates were 38% (I), 42% (H) and 48% (G), over a period of 168 h with COD reduction being highest at near neutral pH. PMID:27148718

  6. Experiments with Plasmas Produced by Potassium-Seeded Cyanogen Oxygen Flames for Study of Radio Transmission at Simulated Reentry Vehicle Plasma Conditions

    NASA Technical Reports Server (NTRS)

    Huber, Paul W.; Gooderum, Paul B.

    1961-01-01

    A method for the chemical production of an ionized gas stream for application to radio transmission studies is described. Involved is the combustion of gaseous cyanogen and oxygen with the addition of vaporized potassium in some cases to further increase the ionization. Experiments are described in which a 3-inch-diameter subsonic free jet at atmospheric pressure is used, and the results are presented. The plasma obtained by using this method is sufficient to simulate plasma conditions expected for reentering hypersonic vehicles. The unseeded plasma stream temperature is indicated to be about 4,200 K, with the degree of ionization indicated to be that expected from thermal equilibrium considerations. Measurements of radio-signal loss due to the unseeded flame plasma are presented for microwaves of 8 to 20 kmc transmitted through the stream and for a dipole transmitting model of 219.5 mc immersed in the stream. Favorable comparison of these results with the simple plane-wave signal-attenuation theory was obtained. In the case of a 9.4-kmc microwave signal of 30-kw peak power, the preliminary indication is that the plasma characteristics were not changed due to this strong signal. Comparison of a simplified concept of radio-signal attenuation due to plasmas is made with some hypersonic reentry vehicle signal-loss data. Other areas of plasma research using this method for the transmission problem are indicated.

  7. Purification of labeled cyanogen bromide peptides of the alpha polypeptide from sodium ion and potassium ion activated adenosinetriphosphatase modified with N-(/sup 3/H)ethylmaleimide

    SciTech Connect

    Le, D.T.

    1986-05-06

    Sodium ion and potassium ion activated adenosinetriphosphatase, isolated from canine kidney, was reacted with N-(/sup 3/H)ethylmaleimide while it was poised in three different conformations, ostensibly E2-P, E2, and E1, respectively. These assignments were made from a consideration of the particular concentrations of ligands in the respective alkylation mixtures. After a 30-min reaction, the remaining enzymatic activity was found to vary among these three different samples from 90 to 30% of that of unalkylated controls. In all cases, the alpha polypeptide was purified and subjected to digestion with cyanogen bromide, and in each digest the same two distinct radioactive peptides were identified and purified by gel filtration on a column of Sephadex LH-60. The incorporation of N-(/sup 3/H)ethylmaleimide into one of these two peptides correlated closely with enzymatic inactivation, while the incorporation into the other was most extensive when the portion of the active site to which ATP binds was unoccupied. Alkylation of the residue within the latter peptide, however, does not result in inactivation of the enzyme. Both peptides were further purified by high-pressure liquid chromatography, and their amino-terminal sequences were determined by manual dansyl Edman or solid-phase techniques. The peptide containing the sulfhydryl protected by ATP has, as its amino terminus, the lysine that reacts exclusively with fluoresceinyl 5'-isothiocyanate.

  8. Metabolism of Monoterpenes : Early Steps in the Metabolism of d-Neomenthyl-beta-d-Glucoside in Peppermint (Mentha piperita) Rhizomes.

    PubMed

    Croteau, R; Sood, V K; Renstrøm, B; Bhushan, R

    1984-11-01

    Previous studies have shown that the monoterpene ketone l-[G-(3)H] menthone is reduced to the epimeric alcohols l-menthol and d-neomenthol in leaves of flowering peppermint (Mentha piperita L.), and that a portion of the menthol is converted to menthyl acetate while the bulk of the neomenthol is transformed to neomenthyl-beta-d-glucoside which is then transported to the rhizome (Croteau, Martinkus 1979 Plant Physiol 64: 169-175). Analysis of the disposition of l-[G-(3)H]menthone applied to midstem leaves of intact flowering plants allowed the kinetics of synthesis and transport of the monoterpenyl glucoside to be determined, and gave strong indication that the glucoside was subsequently metabolized in the rhizome. Studies with d-[G-(3)H]neomenthyl-beta-d-glucoside as substrate, using excised rhizomes or rhizome segments, confirmed the hydrolysis of the glucoside as an early step in metabolism at this site, and revealed that the terpenoid moiety was further converted to a series of ether-soluble, methanol-soluble, and water-soluble products. Studies with d-[G-(3)H]neomenthol as the substrate, using excised rhizomes, showed the subsequent metabolic steps to involve oxidation of the alcohol back to menthone, followed by an unusual lactonization reaction in which oxygen is inserted between the carbonyl carbon and the carbon bearing the isopropyl group, to afford 3,4-menthone lactone. The conversion of menthone to the lactone, and of the lactone to more polar products, were confirmed in vivo using l-[G-(3)H]menthone and l-[G-(3)H]-3,4-menthone lactone as substrates. Additional oxidation products were formed in vivo via the desaturation of labeled neomenthol and/or menthone, but none of these transformations appeared to lead to ring opening of the p-menthane skeleton. Each step in the main reaction sequence, from hydrolysis of neomenthyl glucoside to lactonization of menthone, was demonstrated in cell-free extracts from the rhizomes of flowering mint plants. The

  9. The Metabolic Fate of Deoxynivalenol and Its Acetylated Derivatives in a Wheat Suspension Culture: Identification and Detection of DON-15-O-Glucoside, 15-Acetyl-DON-3-O-Glucoside and 15-Acetyl-DON-3-Sulfate

    PubMed Central

    Schmeitzl, Clemens; Warth, Benedikt; Fruhmann, Philipp; Michlmayr, Herbert; Malachová, Alexandra; Berthiller, Franz; Schuhmacher, Rainer; Krska, Rudolf; Adam, Gerhard

    2015-01-01

    Deoxynivalenol (DON) is a protein synthesis inhibitor produced by the Fusarium species, which frequently contaminates grains used for human or animal consumption. We treated a wheat suspension culture with DON or one of its acetylated derivatives, 3-acetyl-DON (3-ADON), 15-acetyl-DON (15-ADON) and 3,15-diacetyl-DON (3,15-diADON), and monitored the metabolization over a course of 96 h. Supernatant and cell extract samples were analyzed using a tailored LC-MS/MS method for the quantification of DON metabolites. We report the formation of tentatively identified DON-15-O-β-D-glucoside (D15G) and of 15-acetyl-DON-3-sulfate (15-ADON3S) as novel deoxynivalenol metabolites in wheat. Furthermore, we found that the recently identified 15-acetyl-DON-3-O-β-D-glucoside (15-ADON3G) is the major metabolite produced after 15-ADON challenge. 3-ADON treatment led to a higher intracellular content of toxic metabolites after six hours compared to all other treatments. 3-ADON was exclusively metabolized into DON before phase II reactions occurred. In contrast, we found that 15-ADON was directly converted into 15-ADON3G and 15-ADON3S in addition to metabolization into deoxynivalenol-3-O-β-D-glucoside (D3G). This study highlights significant differences in the metabolization of DON and its acetylated derivatives. PMID:26274975

  10. The Metabolic Fate of Deoxynivalenol and Its Acetylated Derivatives in a Wheat Suspension Culture: Identification and Detection of DON-15-O-Glucoside, 15-Acetyl-DON-3-O-Glucoside and 15-Acetyl-DON-3-Sulfate.

    PubMed

    Schmeitzl, Clemens; Warth, Benedikt; Fruhmann, Philipp; Michlmayr, Herbert; Malachová, Alexandra; Berthiller, Franz; Schuhmacher, Rainer; Krska, Rudolf; Adam, Gerhard

    2015-08-01

    Deoxynivalenol (DON) is a protein synthesis inhibitor produced by the Fusarium species, which frequently contaminates grains used for human or animal consumption. We treated a wheat suspension culture with DON or one of its acetylated derivatives, 3-acetyl-DON (3-ADON), 15-acetyl-DON (15-ADON) and 3,15-diacetyl-DON (3,15-diADON), and monitored the metabolization over a course of 96 h. Supernatant and cell extract samples were analyzed using a tailored LC-MS/MS method for the quantification of DON metabolites. We report the formation of tentatively identified DON-15-O-β-D-glucoside (D15G) and of 15-acetyl-DON-3-sulfate (15-ADON3S) as novel deoxynivalenol metabolites in wheat. Furthermore, we found that the recently identified 15-acetyl-DON-3-O-β-D-glucoside (15-ADON3G) is the major metabolite produced after 15-ADON challenge. 3-ADON treatment led to a higher intracellular content of toxic metabolites after six hours compared to all other treatments. 3-ADON was exclusively metabolized into DON before phase II reactions occurred. In contrast, we found that 15-ADON was directly converted into 15-ADON3G and 15-ADON3S in addition to metabolization into deoxynivalenol-3-O-β-D-glucoside (D3G). This study highlights significant differences in the metabolization of DON and its acetylated derivatives. PMID:26274975