coniferin and syringin

Monolignol glucosides and their β-glucosidases are found in monocots, but their biological roles are unclear. Phylogenetic analysis of rice (Oryza sativa L.) glycoside hydrolase family GH1 β-glucosidases indicated that Os4BGlu14, Os4BGlu16, and Os4BGlu18 are closely related to known monolignol β-glucosidases. An optimized Os4BGlu16 cDNA and cloned Os4BGlu18 cDNA were used to express fusion proteins with His6 tags in Pichia pastoris and Escherichia coli, respectively. The secreted Os4BGlu16 fusion protein was purified from media by immobilized metal affinity chromatography (IMAC), while Os4BGlu18 was extracted from E. coli cells and purified by anion exchange chromatography, hydrophobic interaction chromatography and IMAC. Os4BGlu16 and Os4BGlu18 hydrolyzed the monolignol glucosides coniferin (kcat/KM, 21.6mM(-1)s(-1) for Os4BGlu16 and for Os4BGlu18) and syringin (kcat/KM, 22.8mM(-1)s(-1) for Os4BGlu16 and 24.0mM(-1)s(-1) for Os4BGlu18) with much higher catalytic efficiencies than other substrates. In quantitative RT-PCR, highest Os4BGlu14 mRNA levels were detected in endosperm, embryo, lemma, panicle and pollen. Os4BGlu16 was detected highest in leaf from 4 to 10 weeks, endosperm and lemma, while Os4BGlu18 mRNA was most abundant in vegetative stage from 1 week to 4 weeks, pollen and lemma. These data suggest a role for Os4BGlu16 and Os4BGlu18 monolignol β-glucosidases in both vegetative and reproductive rice tissues.

Topics: Amino Acid Sequence; beta-Glucosidase; Cellulases; Cinnamates; DNA, Complementary; Escherichia coli; Flowers; Genes, Plant; Glucosides; Lignin; Molecular Sequence Data; Oryza; Phenylpropionates; Phylogeny; Pichia; Plant Leaves; Plant Proteins; Plant Structures; RNA, Messenger; Seeds

Monolignol glucosides are thought to be implicated in the lignin biosynthesis pathway as storage and/or transportation forms of cinnamyl alcohols between the cytosol and the lignifying cell walls. The hydrolysis of these monolignol glucosides would involve β-glucosidase activities. In Arabidopsis (Arabidopsis thaliana), in vitro studies have shown the affinity of β-GLUCOSIDASE45 (BGLU45) and BGLU46 for monolignol glucosides. BGLU45 and BGLU46 genes are expressed in stems. Immunolocalization experiments showed that BGLU45 and BGLU46 proteins are mainly located in the interfascicular fibers and in the protoxylem, respectively. Knockout mutants for BGLU45 or BGLU46 do not have a lignin-deficient phenotype. Coniferin and syringin could be detected by ultra-performance liquid chromatography-mass spectrometry in Arabidopsis stems. Stems from BGLU45 and BGLU46 mutant lines displayed a significant increase in coniferin content without any change in coniferyl alcohol, whereas no change in syringin content was observed. Other glucosylated compounds of the phenylpropanoid pathway were also deregulated in these mutants, but to a lower extent. By contrast, BGLU47, which is closely related to BGLU45 and BGLU46, is not implicated in either the general phenylpropanoid pathway or in the lignification of stems and roots. These results confirm that the major in vivo substrate of BGLU45 and BGLU46 is coniferin and suggest that monolignol glucosides are the storage form of monolignols in Arabidopsis, but not the direct precursors of lignin.

Topics: Arabidopsis; Arabidopsis Proteins; Cellulases; Cinnamates; DNA, Bacterial; Gene Expression Profiling; Gene Expression Regulation, Plant; Genes, Plant; Glucosides; Lignin; Metabolome; Mutagenesis, Insertional; Mutation; Organ Specificity; Phenylpropionates; Plant Roots; Plant Stems; Protein Transport; Reverse Transcriptase Polymerase Chain Reaction

To study the chemical constituents from the stems of Acanthopanax gracilistylus.. The chemical constituents of the plant were isolated and puried by column chromatography and their structures were elucidated on the basis of physico-chemical properties and spectral data.. Sixteen compounds were isolated and identified as (2S,3S, 4R, 8E)-2-[(2'R)-2'-hydroxy-pentadecanoylamino]-heptacosane-1,3,4-triol-8-ene(1a),(2S,3S,4R,8E)-2-[(2'R)-2'-hydroxy-octadecanoylamino]-lignocer-ane-1,3,4-triol-8-ene(1b), (2S, 3S, 4R, 8E) -2-[(2'R) -2'-hydroxy-heneicosanoylamino]-heneicosane-1,3,4-triol-8-ene (1c), (2S, 3S,4R, 8E)-2-[(2'R) -2'-hydroxy-docosanoylamino] -eicosane-1,3,4-triol-8-ene (1d), (2S, 3S, 4R, 8E)-2-[(2'R)-2'-hydroxy-trico-sanoylamino]-nonadecane-1,3,4-triol-8-ene (1e), (2S,3S,4R,8E)-2-[(2'R)-2'-hydroxy-lignocera-noylamino]-cctadecane-1,3,4-tri-ol-8-ene(1f), 1-O-beta-D-glucopyranosyl-(2S, 3S, 4R, 8E)-2-[(2'R)-2'-hydroxy-pentadecanoylamino]-nonadecane-1, 3, 4-triol-8-ene (2), 16alpha-hydroxy-ent-kauran-19-ocid (3), 16alphaH, 17-isovaleryloxy-ent-kauran-19-oic acid (4), coniferin (5), syringin (6), eleutheroside D (7), stigmasterol (8), beta-sitosterol (9), daucosterol (10), pentacosanoic acid (11).. Compounds 1a - f, 2 are isolated from this genus for the first time, and compounds 4, 5, 11 are firstly obtained from Acanthopanax gracilistylus.

Topics: Cinnamates; Eleutherococcus; Glucosides; Magnetic Resonance Spectroscopy; Molecular Structure; Phenylpropionates; Plant Extracts; Plant Stems; Plants, Medicinal; Sitosterols; Stigmasterol

To investigate the chemical constituents of the aerial parts of Ammopiptanthus mongolicus.. The chemical constituents were isolated by various column chromatographic methods. The structures were identified by spectral data.. Ten compounds were isolated and identified as m-hydroxybenzoic acid (1), 1-(4-hydroxyphenyl) ethanone (2), beta-sitosterol (3), (-)-syringaresinol (4), (+)-lariciresinol (5), blumenol A (6), blumenol B (7), beta-daucosterol (8), coniferin (9), syringin (10).. The ten compounds were obtained from the genus Ammopiptanthus for the first time.

Topics: Cinnamates; Cyclohexanones; Drugs, Chinese Herbal; Fabaceae; Glucosides; Magnetic Resonance Spectroscopy; Phenylpropionates; Plant Components, Aerial; Sitosterols

Three phenylpropanoid glycosides (salidroside, syringin and coniferin) and one lignan (phillyrin) isolated from the leaves of Phillyrea latifolia L. (Oleaceae) were tested for interactions with the cyclo-oxygenase and 5-lipoxygenase pathways of arachidonate metabolism in calcium-stimulated mouse peritoneal macrophages and human platelets, and for their effects on cell viability. These compounds are capable of exerting inhibitory actions on enzymes of the arachidonate cascade. Phillyrin, salidroside and syringin exert a preferential effect on the cyclo-oxygenase pathway, inhibiting release of the cyclo-oxygenase metabolites prostaglandin E2 (IC50 values 45.6 microM, 72.1 microM and 35.5 microM, respectively) and to a lesser extent reducing thromboxane B2 levels (IC50 values 168 microM, 154 microM and 29.3 microM, respectively). In contrast, coniferin can be classified as a "dual inhibitor", since it produces reduction in generation of both cyclo-oxygenase (IC50 values 75.2 microM for prostaglandin E2 and 619 microM for thromboxane B2) and 5-lipoxygenase metabolites, but the effects are greater against leukotriene C4 (IC50 value 63.6 microM). Structure-activity relationships of the three phenylpropanoid glycosides are discussed. Thus, like some other compounds found in medicinal herbs, our molecules possess an array of potentially beneficial anti-eicosanoid properties which may, alongside other constituents, contribute to the claimed therapeutic properties of the plant from which they are derived.

Topics: Animals; Anti-Infective Agents; Anti-Inflammatory Agents; Blood Platelets; Cells, Cultured; Cinnamates; Dinoprostone; Drug Interactions; Eicosanoids; Female; Glucosides; Glycosides; Humans; Ionophores; Leukotriene C4; Macrophages, Peritoneal; Magnoliopsida; Male; Mice; Phenols; Phenylpropionates; Plants, Medicinal; Thromboxane B2

The fraction containing glycosidic components was separated from flue-cured tobacco (Nicotiana tabacum L.) leaves by a facile method. Some components of the fraction were isolated and elucidated to be syringin, coniferin, cichoriin, benzyl-beta-D-glucoside, Blumenol A-beta-D-glucoside, and 5,6-epoxy-5,6-dihydro-3-hydroxy-beta-ionyl-beta-D-glucoside. Syringin and coniferin were detected in the Nicotiana species for the first time.

Topics: Benzopyrans; Carbohydrate Conformation; Chemical Fractionation; Cinnamates; Cyclohexanones; Glucosides; Glycosides; Nicotiana; Phenylpropionates; Plant Extracts; Plants, Toxic

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.

Topics: Acetylation; Cinnamates; Glucosides; Isomerism; Lignin; Phenylpropionates; Trees