- Thermal Behavior of d-Ribose Adsorbed on Silica: Effect of Inorganic Salt Coadsorption and Significance for Prebiotic Chemistry
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Understanding ribose reactivity is a crucial step in the “RNA world” scenario because this molecule is a component of all extant nucleotides that make up RNA. In solution, ribose is unstable and susceptible to thermal destruction. We examined how ribose behaves upon thermal activation when adsorbed on silica, either alone or with the coadsorption of inorganic salts (MgCl2, CaCl2, SrCl2, CuCl2, FeCl2, FeCl3, ZnCl2). A combination of13C NMR, in situ IR, and TGA analyses revealed a variety of phenomena. When adsorbed alone, ribose remains stable up to 150 °C, at which point ring opening is observed, together with minor oxidation to a lactone. All the metal salts studied showed specific interactions with ribose after dehydration, resulting in the formation of polydentate metal ion complexes. Anomeric equilibria were affected, generally favoring ribofuranoses. Zn2+stabilized ribose up to higher temperatures than bare silica (180 to 200 °C). Most other cations had an adverse effect on ribose stability, with ring opening already upon drying at 70 °C. In addition, alkaline earth cations catalyzed the dehydration of ribose to furfural and, to variable degrees, its further decarbonylation to furan. Transition-metal ions with open d-shells took part in redox reactions with ribose, either as reagents or as catalysts. These results allow the likelihood of prebiotic chemistry scenarios to be evaluated, and may also be of interest for the valorization of biomass-derived carbohydrates by heterogeneous catalysis.
- Akouche, Mariame,Jaber, Maguy,Zins, Emilie-Laure,Maurel, Marie-Christine,Lambert, Jean-Francois,Georgelin, Thomas
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- Comprehensive investigation of the energetics of pyrimidine nucleoside formation in a model prebiotic reaction
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The problem of β-nucleoside formation under prebiotic conditions represents one of the most significant challenges to the "RNA world" hypothesis. The possibility exists that alternative bases may have come before the contemporary bases (i.e., A, G, C, and
- Sheng, Yinghong,Bean, Heather D.,Mamajanov, Irena,Hud, Nicholas V.,Leszczynski, Jerzy
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- New bisamide compounds from the bark of Aglaia eximia (Meliaceae)
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Two new bisamide compounds, eximiamide A (1) and eximiamide B (2) were isolated from the bark of Aglaia eximia (Meliaceae). The chemical structures of the new compound were elucidated on the basis of spectroscopic data. All of the compounds were evaluated for their cytotoxic effects against P-388 murine leukemia cells. Compounds 1 and 2 exhibited cytotoxic activity against P-388 murine leukemia cells with IC50 values of 7.6 and 8.5 μg/mL, respectively.
- Sianturi, Julinton,Purnamasari, Mayshah,Darwati,Harneti, Desi,Mayanti, Tri,Supratman, Unang,Awang, Khalijah,Hayashi, Hideo
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- Biosynthesis of anti-HCV compounds using thermophilic microorganisms
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This work describes the application of thermophilic microorganisms for obtaining 6-halogenated purine nucleosides. Biosynthesis of 6-chloropurine- 2′-deoxyriboside and 6-chloropurine riboside was achieved by Geobacillus stearothermophilus CECT 43 with a conversion of 90% and 68%, respectively. Furthermore, the selected microorganism was satisfactorily stabilized by immobilization in an agarose matrix. This biocatalyst can be reused at least 70 times without significant loss of activity, obtaining 379 mg/L of 6-chloropurine-2′-deoxyriboside. The obtained compounds can be used as antiviral agents.
- Rivero, Cintia W.,De Benedetti, Eliana C.,Sambeth, Jorge E.,Lozano, Mario E.,Trelles, Jorge A.
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- Isochromans and related constituents from the endophytic fungus Annulohypoxylon truncatum of Zizania caduciflora and their anti- inflammatory effects
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Six new isochroman derivatives (annulohypoxylomans A-C, 1-3; annulohypoxylomanols A and B, 6 and 7; and annulohypoxyloside, 8), an isocoumarin (annulohypoxylomarin A, 4), and an azaphilone derivative (xylariphilone, 5) were isolated from an ethyl acetate extract derived from cultures of the endophytic fungus JS540 found in the leaves of Zizania caducif lora. The JS540 strain was identified as Annulohypoxylon truncatum. The structures of the isolated compounds were elucidated by one- and two-dimensional nuclear magnetic resonance and mass spectrometry and by comparison with related compounds from the literature. The anti-inflammatory activities of the isolated compounds were evaluated in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells. Xylariphilone (5) exhibited significant inhibitory effects on LPS-induced interleukin (IL)-6, IL-12 p40, and tumor necrosis factor (TNF)-α production with IC50 values of 5.3, 19.4, and 37.6 μM, respectively. (Chemical Equation Presented).
- Li, Wei,Lee, Changyeol,Bang, Sung Hee,Ma, Jin Yeul,Kim, Soonok,Koh, Young-Sang,Shim, Sang Hee
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- Two new secondary metabolites from a mangrove-derived fungus Cladosporium sp. JJM22
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Two new compounds (1 and 2), together with six known compounds (3–8), were obtained from the Cladosporium sp. JJM22, an endophytic fungus isolated from the stem bark of the mangrove plant Ceriops tagal collected in South China Sea. Their structures were elucidated on the basis of detailed spectroscopic analysis. The absolute configurations of 1 and 2 were confirmed by the comparison of optical rotation and the CD data with those of known compounds. The inhibitory activities of the isolated compounds against six terrestrial pathogenic bacteria and human cervical carcinoma Hela cell line were evaluated. Compound 3 exhibited a broad spectrum of antibacterial activities.
- Wu, Jia-Ting,Zheng, Cai-Juan,Zhang, Bin,Zhou, Xue-Ming,Zhou, Qi,Chen, Guang-Ying,Zeng, Zhuo-Er,Xie, Jin-Long,Han, Chang-Ri,Lyu, Ji-Xing
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- Biochemical characterization of a recombinant acid phosphatase from Acinetobacter baumannii
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Genomic sequence analysis of Acinetobacter baumannii revealed the presence of a putative Acid Phosphatase (AcpA; EC 3.1.3.2). A plasmid construct was made, and recombinant protein (rAcpA) was expressed in E. coli. PAGE analysis (carried out under denaturing/ reducing conditions) of nickel-affinity purified protein revealed the presence of a nearhomogeneous band of approximately 37 kDa. The identity of the 37 kDa species was verified as rAcpA by proteomic analysis with a molecular mass of 34.6 kDa from the deduced sequence. The dependence of substrate hydrolysis on pH was broad with an optimum observed at 6.0. Kinetic analysis revealed relatively high affinity for PNPP (Km = 90 μM) with Vmax, kcat, and Kcat/Km values of 19.2 pmoles s-1, 4.80 s-1(calculated on the basis of 37 kDa), and 5.30 × 104 M-1s-1, respectively. Sensitivity to a variety of reagents, i.e., detergents, reducing, and chelating agents as well as classic acid phosphatase inhibitors was examined in addition to assessment of hydrolysis of a number of phosphorylated compounds. Removal of phosphate from different phosphorylated compounds is supportive of broad, i.e., 'nonspecific' substrate specificity; although, the enzyme appears to prefer phosphotyrosine and/or peptides containing phosphotyrosine in comparison to serine and threonine. Examination of the primary sequence indicated the absence of signature sequences characteristic of Type A, B, and C nonspecific bacterial acid phosphatases.
- Smiley-Moreno, Elizabeth,Smith, Douglas,Yu, Jieh-Juen,Cao, Phuong,Arulanandam, Bernard P.,Chambers, James P.
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- Hypoglycemic triterpenoid glycosides from Cyclocarya paliurus (Sweet Tea Tree)
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Four new rarely occurred seco-dammarane triterpenoid glycosides (1–4) and four new dammarane triterpenoid glycosides (5–8), along with four known triterpenoids (9–12), were isolated from the 70% ethanol extract of the leaves of Cyclocarya paliurus (family Juglandaceae). Their structures were elucidated by extensive spectroscopic methods, including 1D/2D NMR and HRESIMS data, together with chemical analysis and DFT GIAO 13C NMR calculation. In bioassay, compounds 5–8 significantly increased glucose consumption in 3T3-L1 adipocytes, which could be the bioactive constituents for the anti-diabetes effect of the traditional usage of C. paliurus.
- Chen, Zuhui,Li, Jing,Lv, Wenyan,Sun, Huihui,Tan, Jie,Wang, Wenxuan,Wu, Jianping,Xu, Jialing,Xu, Kangping,Xuan, Tongyao,Yang, Zhichun,Ye, Zijun,Zhu, Hui,Zou, Zhenxing
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- ELECTROCHEMICAL METHODS AND SYSTEMS FOR PRODUCING MONOSACCHARIDES
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The present disclosure is related to electrochemical methods of forming monosaccharides, and systems for generating the same. A benefit of the methods and systems disclosed herein can include the sustainable production of monosaccharides in an automated process. A benefit of the methods and systems herein can be the generation of monosaccharides from renewable source materials. An additional benefit of the methods and systems herein can include the use of abundant feedstocks, such as carbon dioxide, for the efficient generation of select monosaccharides for use as nutrients and for other useful applications. Another benefit of the methods and systems disclosed herein can include reduction of excess carbon dioxide from the environment.
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Paragraph 0067-0068
(2020/07/15)
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- Kinase-Inhibitory Nucleoside Derivatives from the Pacific Bryozoan Nelliella nelliiformis
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Marine organisms are a valuable source of bioactive natural products, yet bryozoan invertebrates have been relatively understudied. Herein, we report nelliellosides A and B, new secondary metabolites of the Pacific bryozoan Nelliella nelliiformis, found using NMR-guided isolation. Their structures, including absolute configurations, were elucidated using spectroscopic and chromatographic techniques. Total synthesis of the natural products and four analogues was also achieved, in addition to an assessment of their biological activity, especially kinase inhibition.
- Bracegirdle, Joe,Gordon, Dennis P.,Harvey, Joanne E.,Keyzers, Robert A.
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p. 547 - 551
(2020/03/19)
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- Production of keto-pentoses: Via isomerization of aldo-pentoses catalyzed by phosphates and recovery of products by anionic extraction
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Xylulose and ribulose are rare keto-pentoses which are in high demand for the synthesis of commodities and fine chemicals. The production of keto-pentoses via isomerization of aldo-pentoses presents a carbon-efficient synthetic method. However, the isomerizations are equilibrium processes with thermodynamically limited yields of the products. In this work we examined isomerization of aldo-pentoses into keto-pentoses in the presence of NaH2PO4 + Na2HPO4 as a soluble catalyst at pH 7.5. A reaction network was proposed based on product distribution with d-(1-13C)-ribose as a substrate. Additionally, kinetics of the isomerization reactions was addressed. Selectivity for the keto-pentoses dramatically depends on the structure of the substrate. Arabinose and xylose give rise to a number of isomeric pentoses with low selectivities for the target products. Investigation of the reaction kinetics suggests that xylose and arabinose slowly isomerize into xylulose and ribulose, respectively. The latter react further significantly quicker to produce a number of isomers as subsequent products. This causes a complex mixture of products with low selectivity for the keto-pentoses. In contrast, ribose and lyxose as substrates yield ribulose and xylulose with rather high selectivities of 68-79% at 20% conversion. Ribose and lyxose quickly isomerize into ribulose and xylulose, respectively, whereas the subsequent processes are relatively slow. This results in a high selectivity for the keto-pentoses based on ribose and lyxose. Moreover, the isolation of xylulose from the reaction mixture was also studied. Xylulose can be selectively recovered after the isomerization of lyxose using anionic extraction with o-hydroxymethyl phenylboronic acid (HMPBA). After extraction, the aqueous phase containing phosphates and remaining lyxose can be recycled. After four cycles, the yield of xylulose reached 37% though only 19% can be achieved under batch conditions. Xylulose can be further recovered from the organic phase by back extraction using an acidified solution. Ribulose can also be extracted as an anionic complex with HMPBA, though ribose is co-extracted in this case and a separation of ribulose from ribose cannot be achieved. Extraction of the keto-pentoses occurs due to formation of β-xylulose-HMPBA and α-ribulose-HMPBA anionic complexes, whose molecular structures were established by NMR and MS.
- Delidovich, Irina,Gyngazova, Maria S.,Sánchez-Bastardo, Nuria,Wohland, Julia P.,Hoppe, Corinna,Drabo, Peter
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p. 724 - 734
(2018/02/14)
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- NOVEL LACTIC ACID BACTERIUM
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This invention provides lactic acid bacteria that have one or more effects selected from among fatigue-ameliorating effect, blood circulation-improving effect, stool odor-reducing effect, and growth-promoting effect and that can be used with high safety. This invention further provides a pharmaceutical preparation comprising, as an active ingredient, lactic acid bacteria that have one or more effects selected from among fatigue-ameliorating effect, blood circulation-improving effect, stool odor-reducing effect, and growth-promoting effect. According to the invention, novel lactic acid bacteria belonging to the Enterococcus faecium species having particular mycological properties and exhibiting viability of 40% or higher when freeze-dried in the absence of a dispersion medium and viability of 80% or higher in a probiotic preparation when stored at 40° C. for 4 months, a composition comprising such lactic acid bacteria, an agent for ameliorating fatigue, improving blood circulation, reducing stool odor or promoting growth comprising, as an active ingredient, such composition, and use of such composition for food and other products.
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- Structural diversity of Burkholderia pseudomallei lipopolysaccharides affects innate immune signaling
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Burkholderia pseudomallei (Bp) causes the disease melioidosis. The main cause of mortality in this disease is septic shock triggered by the host responding to lipopolysaccharide (LPS) components of the Gram-negative outer membrane. Bp LPS is thought to be a weak inducer of the host immune system. LPS from several strains of Bp were purified and their ability to induce the inflammatory mediators TNF-α and iNOS in murine macrophages at low concentrations was investigated. Innate and adaptive immunity qPCR arrays were used to profile expression patterns of 84 gene targets in response to the different LPS types. Additional qPCR validation confirmed large differences in macrophage response. LPS from a high-virulence serotype B strain 576a and a virulent rough central nervous system tropic strain MSHR435 greatly induced the innate immune response indicating that the immunopathogenesis of these strains is different than in infections with strains similar to the prototype strain 1026b. The accumulation of autophagic vesicles was also increased in macrophages challenged with highly immunogenic Bp LPS. Gene induction and concomitant cytokine secretion profiles of human PBMCs in response to the various LPS were also investigated. MALDI-TOF/TOF was used to probe the lipid A portions of the LPS, indicating substantial structural differences that likely play a role in host response to LPS. These findings add to the evolving knowledge of host-response to bacterial LPS, which can be used to better understand septic shock in melioidosis patients and in the rational design of vaccines.
- Norris, Michael H.,Schweizer, Herbert P.,Tuanyok, Apichai
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- Molecular structure, chemical properties and biological activities of Pinto bean pod polysaccharide
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Pinto bean pod polysaccharide (PBPP) was successfully extracted with yield of 38.5 g/100 g and the PBPP gave total carbohydrate and uronic acid contents of 286.2 mg maltose equivalent/g and 374.3 mg Gal/g, respectively. The Mw of PBPP was 270.6 kDa with intrinsic viscosity of 0.262 dm3/g, which composed of mannose (2.5%), galacturonic acid (15.0%), rhamnose (4.0%), glucose (9.0%), galactose (62.2%), xylose (2.9%) and arabinose (4.3%) with trace amount of ribose and fucose. The result suggested that PBPP has a spherical conformation with a highly branched structure. Fourier Transform Infrared analysis showed that PBPP has a similar structure as commercial pectin with an esterification degree of 59.9%, whereas scanning electron microscopy study showed that the crude polysaccharide formed a thin layer of film that was made of multiple micro strands of fibre. PBPP exhibited substantial free radical scavenging activity (7.7%), metal reducing capability (2.04 mmol/dm3) and α-amylase inhibitory activity (97.6%) at a total amount of 1 mg. PBPP also exhibited high water- and oil-holding capacities (3.6 g/g and 2.8 g/g, respectively). At a low concentration, PBPP exhibited emulsifying activity of 39.6% with stability of 38.6%. Apart from that, PBPP was able to show thickening capability at low concentration (0.005 kg/dm3).
- Kamarudin, Fazlina,Gan, Chee-Yuen
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p. 280 - 287
(2016/04/19)
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- Catalyst and Process Design for the Continuous Manufacture of Rare Sugar Alcohols by Epimerization–Hydrogenation of Aldoses
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Sugar alcohols are applied in the food, pharmaceutical, polymer, and fuel industries and are commonly obtained by reduction of the corresponding saccharides. In view of the rarity of some sugar substrates, epimerization of a readily available monosaccharide has been proposed as a solution, but an efficient catalytic system has not yet been identified. Herein, a molybdenum heteropolyacid-based catalyst is developed to transform glucose, arabinose, and xylose into less-abundant mannose, ribose, and lyxose, respectively. Adsorption of molybdic acid onto activated carbon followed by ion exchange to the cesium form limits leaching of the active phase, which greatly improves the catalyst stability over 24 h on stream. The hydrogenation of mixtures of epimers is studied over ruthenium catalysts, and it is found that the precursor to the desired polyol is advantageously converted with faster kinetics. This is explained by density functional theory on the basis of its more favorable adsorption on the metal surface and the lower energy barrier for the addition of a hydrogen atom to the primary carbon atom. Finally, different designs for a continuous process for the conversion of glucose into mannitol are studied, and it is uncovered that two reactors in series with one containing the epimerization catalyst and the other containing a mixture of the epimerization and hydrogenation catalysts increases the mannitol/sorbitol ratio to 1.5 from 1 for a single mixed-bed reactor. This opens a prospective route to the efficient valorization of renewables to added-value chemicals.
- Lari, Giacomo M.,Gr?ninger, Olivier G.,Li, Qiang,Mondelli, Cecilia,López, Núria,Pérez-Ramírez, Javier
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p. 3407 - 3418
(2016/12/27)
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- Structure of a new pseudaminic acid-containing capsular polysaccharide of Acinetobacter baumannii LUH5550 having the KL42 capsule biosynthesis locus
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The capsular polysaccharide from Acinetobacter baumannii LUH5550 was studied by 1D and 2D 1H and 13C NMR spectroscopy. The following structure of the branched trisaccharide repeating unit was established: (Formula presented.) where Pse5Ac7RHb indicates 5-acetamido-3,5,7,9-tetradeoxy-7-[(R)-3-hydroxybutanoylamino]-l-glycero-l-manno-non-2-ulosonic acid. The genes in the capsule biosynthesis locus designated KL42 are consistent with the structure established.
- Senchenkova, Sof'ya N.,Popova, Anastasiya V.,Shashkov, Alexander S.,Shneider, Mikhail M.,Mei, Zhu,Arbatsky, Nikolay P.,Liu, Bin,Miroshnikov, Konstantin A.,Volozhantsev, Nikolay V.,Knirel, Yuriy A.
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p. 154 - 157
(2015/03/30)
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- Efficient Epimerization of Aldoses Using Layered Niobium Molybdates
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Both non-acidic LiNbMoO6 and strongly acidic HNbMoO6 efficiently catalyze the epimerization of sugars including glucose, mannose, xylose, and arabinose in water. The reactions over these oxides reached almost equilibrium within a few hours where yields of corresponding epimers from glucose, xylose, and arabinose were 24-29 %. The layered mixed oxides functioned as heterogeneous catalysts and could be reused without loss of activity, whereas bulk molybdenum oxide MoO3 was completely dissolved during the reaction. A 13C substitution experiment showed that the reaction proceeds through a 1,2-rearrangement mechanism. The surface Mo octahedra were responsible for the activity. The layered HNbMoO6 could also afford mannose from cellobiose through hydrolysis and successive epimerization.
- Takagaki, Atsushi,Furusato, Shogo,Kikuchi, Ryuji,Oyama, S. Ted
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p. 3769 - 3772
(2015/12/08)
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- Purification and structural data of a highly substituted exopolysaccharide from Pseudomonas stutzeri AS22
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Pseudomonas stutzeri AS22, when grown on media containing starch and yeast extract and incubated at 30 °C and 200 rpm for 24 h, was found to produce an acidic and high-molecular mass exopolysaccharide (EPS22). The EPS22 was purified and a yield of 1.3 g/l was achieved. The average molecular mass of the EPS22 was determined by high-performance size-exclusion chromatography (HPSEC) and showed an average molecular mass of 9.9 × 105 Da and a polydispersity index Mw/Mn (Mw, weight-average and Mn, number-average) of 1.197 ± 0.015. Structural data of this EPS22 were determined using a combination approach including monosaccharide composition (HPAEC-PAD and GLC), methylation analysis (GC-MS) and NMR spectroscopy analysis. EPS22 was found to be a complex heteropolysaccharide with a repeating unit mainly composed of glucose, mannose and lactyl rhamnose in a molar ratio of 1:1.1:0.7. The acidic nature of the polysaccharide is due to the presence of three non-osidic substituents consisting of a lactyl, acetyl, and pyruvyl groups.
- Maalej, Hana,Boisset, Claire,Hmidet, Noomen,Buon, Laurine,Heyraud, Alain,Nasri, Moncef
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p. 404 - 411
(2014/07/21)
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- Effects of polysaccharide on chicks co-infected with Bordetella avium and Avian leukosis virus
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Chicks' co-infection with immunosuppressive virus and bacteria seriously threaten the development of the poultry industry. In this study, a model was established in which chicks were injected with either subgroup B ALV (ALV-B) + Bordetella avium (B. avium), or ALV-B + B. avium + Taishan Pinus massoniana pollen polysaccharide (TPPPS), or B. avium only, or B. avium + TPPPS. The data showed that the group injected with ALV-B and B. avium exhibited significant inhibition of the immune function and therefore increased pathogenicity compared with the group injected with B. avium-only. Application of TPPPS effectively alleviated immunosuppression, and body weights increased sharply in the TPPPS groups compared with non-TPPPS groups. To some extent, TPPPS may reduce the proliferation of ALV-B. These results suggest that Pinus pollen polysaccharides are beneficial treating co-infections with immunosuppressive virus and bacteria and therefore have potential for development into safe and effective immunoregulator.
- Guo, Fanxia,Xue, Cong,Wu, Cun,Zhao, Xue,Qu, Tinghe,He, Xiaohua,Guo, Zhongkun,Zhu, Ruiliang
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- Characterization of inosine-uridine nucleoside hydrolase (RihC) from Escherichia coli
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A non-specific nucleoside hydrolase from Escherichia coli (RihC) has been cloned, overexpressed, and purified to greater than 95% homogeneity. Size exclusion chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis show that the protein exists as a homodimer. The enzyme showed significant activity against the standard ribonucleosides with uridine, xanthosine, and inosine having the greatest activity. The Michaelis constants were relatively constant for uridine, cytidine, inosine, adenosine, xanthosine, and ribothymidine at approximately 480 μM. No activity was exhibited against 2′-OH and 3′-OH deoxynucleosides. Nucleosides in which additional groups have been added to the exocyclic N6 amino group also exhibited no activity. Nucleosides lacking the 5′-OH group or with the 2′-OH group in the arabino configuration exhibited greatly reduced activity. Purine nucleosides and pyrimidine nucleosides in which the N7 or N3 nitrogens respectively were replaced with carbon also had no activity.
- Arivett, Brock,Farone, Mary,Masiragani, Ranjith,Burden, Andrew,Judge, Shelby,Osinloye, Adedoyin,Minici, Claudia,Degano, Massimo,Robinson, Matthew,Kline, Paul
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p. 656 - 662
(2014/03/21)
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- A new oleanane-type triterpenoidal saponin from Pulsatilla chinensis
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A new oleanane-type triterpenoidal saponin, 3-O-β-d-glucopyranosyl- hederagenin 23-O-α-d-ribofuranoside (1), was isolated from the roots of Pulsatilla chinensis, and its structure was established on the basis of the spectral data. Compounds 2, 7 and 8 showed moderate cytotoxic activity by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazoliumbromide assay. 2013
- Shu, Zhan,Chen, Zhong,Liu, Yan-Li,Zhu, Wei-Feng,Feng, Yu-Lin,Xu, Qiong-Ming,Li, Xiao-Ran,Yang, Shi-Lin
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p. 2196 - 2201
(2014/01/06)
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- Antitumor and immunomodulatory activities of a polysaccharide from Artemisia argyi
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A water-soluble polysaccharide (FAAP-02), composed of N-acetyl-d- glucosamine, glucose, mannose, galactose, rhamnose arabinose, xylose and ribose, with an average molecular weight of 5169 Da, was isolated from Artemisia argyi. The antitumor and immunomodulatory activities of FAAP-02 were evaluated in Sarcoma 180 (S180) tumor-bearing mice by intraperitoneal administration. As a result, FAAP-02 significantly inhibited the growth of the S180 transplanted tumors and prolonged the survival time of the tumor-bearing mice. Moreover, FAAP-02 could obviously increase the thymus and spleen indices, the levels of serum Interleukin 2 (IL-2), Interleukin 6 (IL-6), Interleukin 12 (IL-12) and tumor necrosis factor- α (TNF-α) and the expression of CD4+ and CD8+ splenic T lymphocytes which were suppressed by the transplanted tumor or/and 5-fluorouracil (5-FU) in the mice. These results indicated that the antitumor activity of FAAP-02 might be associated with its immunostimulatory effects.
- Bao, Xiaoli,Yuan, Huihui,Wang, Chengzhong,Liu, Jinjin,Lan, Minbo
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p. 1236 - 1243
(2013/10/22)
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- Catalytic consequences of borate complexation and pH on the epimerization of l-arabinose to l-ribose in water catalyzed by Sn-Beta zeolite with borate salts
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Sn-Beta zeolite with sodium tetraborate cooperatively catalyzes the epimerization of aldoses via an intramolecular 1,2 carbon-shift mechanism. l-Arabinose is one of the seven common sugars and its epimer, l-ribose, is a valuable rare sugar with applications in antiviral and anticancer agents. Here, a full factorial experimental design is performed to demonstrate the catalytic consequences of varying key reaction parameters such as pH, borate to sugar ratio, and reaction time. Reactivity data revealed that isomerization is favored under acidic pH conditions (pH 7.8). Using a 5 wt% arabinose feed and 100:1 sugar-metal ratios at 343 K, conversions ranging from 20% to 30% were obtained with selectivities of 75%, 84%, and 91% for boron-sugar ratios of 0.2:1, 0.5:1, and 1:1, respectively. The predominance of epimerization over isomerization products with substoichiometric borate suggests that one borate can influence the reactivity of several sugar molecules and may influence the Sn active site directly. Reaction data obtained under differential conditions revealed that the epimerization reaction follows first order kinetics over a wide temperature range with an apparent activation energy of 98 kJ/mol and pre-exponential factor of 1.9 × 1014 L mol Sn-1 s-1.
- Gunther, William R.,Duong, Quynh,Román-Leshkov, Yuriy
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p. 294 - 302
(2013/11/06)
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- Triterpene saponins from clematis mandshurica and their antiproliferative activity
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Six new triterpene saponins, clematomandshurica saponins F-K (1-6), together with a known compound (7), were isolated from the roots and rhizomes of Clematis mandshurica. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis. Compounds 5-7 exhibited antiproliferative effects against PC-3 human prostate cancer cells with GI50 values of 1.29, 1.50, and 0.71 M, respectively.
- Gong, Yi-Xia,Hua, Hui-Ming,Xu, Yong-Nan,Liu, Jian-Yu,Yu, Zong-Gui,Ma, Jing,Zhang, Hui,Jing, Yong-Kui
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p. 987 - 994
(2013/08/23)
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- Three new triterpene saponins from Clematis chinensis
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Three new triterpene saponins, clematochinenosides H-J (1-3), were isolated from the roots and rhizomes of Clematis chinensis. Their structures were elucidated on the basis of spectroscopic means including 1D and 2D NMR experiments and hydrolysis products
- Fu, Qiang,Zan, Ke,Zhao, Ming-Bo,Zhou, Si-Xiang,Shi, She-Po,Jiang, Yong,Tu, Peng-Fei
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p. 610 - 618
(2013/07/26)
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- Analysis of compositional carbohydrates in polysaccharides and foods by capillary zone electrophoresis
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A simple, sensitive and specific analytical method has been established for high efficient separation and simultaneously high sensitive determination of thirteen reducing carbohydrates, including aldohexose and aldopentoses as well as maltose and lactose. Reducing carbohydrates were derivatized with 1-phenyl-3-methyl-5-pyrazolone (PMP), separated by capillary zone electrophoresis (CZE) with use of methanol modifier in 175 mM borate buffer (pH 11.0), and detected by UV at 245 nm. The optimized CZE method was found to be well suited to examine the compositional reducing monosaccharides of the isolated polysaccharides from Lycopus lucidus and Jujube, and free mono- and disaccharides in beer and milk. Quantitative recoveries of the compositional carbohydrates in the samples were in the range of 93.2-104.0%, and RSD values ranged from 2.9% to 4.9%. The developed CZE method proves to be precise and practical for quality control of reducing carbohydrates, and will provide more highly efficient separation in food analysis in the future.
- Wang, Tong,Yang, Xingbin,Wang, Dongying,Jiao, Yadong,Wang, Yu,Zhao, Yan
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experimental part
p. 754 - 762
(2012/06/16)
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- FIBRIN AND FIBRINOGEN MATRICES AND USES OF SAME
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There is provided compositions-of-matter comprising fibrin or fibrinogen crosslinked with at least one reducing sugar.
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- Cytotoxic triterpene saponins from Clematis mandshurica
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Two new triterpene saponins, mandshunosides A and B (1 and 2), were isolated from the roots and rhizomes of Clematis mandshurica. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. Compounds 1 and 2 showed inhibitory activities against two colorectal human cancer cells HCT 116 (IC50 2.1μM for 1 and 2.5μM for 2) and HT-29 (IC50 3.7μM for 1 and 3.3μM for 2).
- He, Yu-Xin,Li, Ling,Zhang, Kang,Liu, Zhong-Rong
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experimental part
p. 1104 - 1109
(2012/02/15)
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- Heterogeneous structure of O-antigenic part of lipopolysaccharide of Salmonella telaviv (Serogroup O:28) containing 3-acetamido-3,6-dideoxy-D- glucopyranose
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The O-polysaccharide of Salmonella Telaviv was obtained by mild acid degradation of the lipopolysaccharide and studied by chemical methods (sugar and methylation analyses, Smith degradation, de-O-acetylation) and NMR spectroscopy. The structure of the O-polysaccharide was established. The repeating units that are proximal to the lipopolysaccharide core region mostly have a digalactose side chain and lack glucose, whereas those at the other end of the chain mostly do bear glucose but are devoid of the disaccharide side chain. This is the first structure established for the O-polysaccharide of a Salmonella serogroup O:28 (formerly M) strain characterized by subfactors O281 and O282. Knowledge of this structure and the structure of the O-polysaccharide of Salmonella Dakar (O281, O28 3) established earlier is crucial for determination of the exact structures associated with subfactors O281, O282, and O283 and elucidation of the genetic basis of the close relationship between Escherichia coli O71 and S. enterica O:28 O-antigens.
- Kumirska,Dziadziuszko,Czerwicka,Lubecka,Kunikowska,Siedlecka,Stepnowski
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experimental part
p. 780 - 790
(2012/01/19)
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- HYBRID COMPOUNDS BASED ON POLYOL(S) AND AT LEAST ONE OTHER MOLECULAR ENTITY, POLYMERIC OR NON-POLYMERIC, IN PARTICULAR OF THE POLYORGANOSILOXANE TYPE, PROCESS FOR THE PREPARATION THEREOF, AND APPLICATIONS THEREOF
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The invention relates to novel hybrid compounds comprising at least one polyon entity (Po)—for example oligomer or polymer—in which at least one of the hydroxyl functions of Po is substituted by at least one entity A that can be of a variable nature, for example polymer (e.g. polyorganosiloxane-POS), hydrocarbonated or mineral. The bond Ro between the entity Po and the entity A is obtained by means of “click chemistry” and corresponds to formula (II.1) or (II.2), Z representing —CH— or —N—. A is an entity selected from the group comprising the various polyols of Po, polyorganosiloxanes (POS), polyalkylene glycols, polyamides, polyesters, polystyrenes, alkyls, alkenyls, alkynyls, aryls, and combinations thereof, in addition to mineral materials such as silica and the combinations thereof. Said hybrid components can be used as emulsifiers, especially for cosmetics.
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- Antioxidant activities of different fractions of polysaccharide purified from pulp tissue of litchi (Litchi chinensis Sonn.)
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Three fractions of water-soluble polysaccharide fractions, coded as LFP1, LFP2 and LFP3, were isolated and purified from litchi pulp by DEAE-52 cellulose anion-exchange column and Sephadex G-100 gel-permeation column. Their chemical and physical characteristics were determined by chemical methods, gas chromatography, IR spectrophotometer and gel-permeation chromatography (GPC) with a model 410 refractive index detector. Antioxidant activities of these fractions were investigated using various in vitro assay systems. Results indicated that LFP1 was composed of arabinose, ribose, galactose and glucose, while LFP2 comprised arabinose, rhamnose and glucose. LFP3 was a heteropolysaccharide bounded with protein (2.6%) and composed of arabinose, rhamnose, galactose and glucose. The molecular weights of LFP1, LFP2 and LFP3 were 11.6 × 104, 3.1 × 104 and 2.9 × 104 Da, respectively. LFP3 showed the highest antioxidant activities among the three fractions of polysaccharides, and could be explored as a novel potential antioxidant.
- Kong, Fan-Li,Zhang, Ming-Wei,Kuang, Rui-Bin,Yu, Shu-Juan,Chi, Jian-Wei,Wei, Zhen-Cheng
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experimental part
p. 612 - 616
(2011/11/12)
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- The rate of spontaneous cleavage of the glycosidic bond of adenosine
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Previous estimates of the rate of spontaneous cleavage of the glycosidic bond of adenosine were determined by extrapolating the rates of the acid- and base-catalyzed reactions to neutral pH. Here we show that cleavage also proceeds through a pH-independent mechanism. Rate constants were determined as a function of temperature at pH 7 and a linear Arrhenius plot was constructed. Uncatalyzed cleavage occurs with a rate constant of 3.7 × 10-12 s-1 at 25 °C, and the rate enhancement generated by the corresponding glycoside hydrolase is ～5 × 1012-fold.
- Stockbridge, Randy B.,Schroeder, Gottfried K.,Wolfenden, Richard
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experimental part
p. 224 - 228
(2010/10/01)
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- Cytotoxic polyketides from a marine-derived fungus Aspergillus glaucus
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Eight new aromatic polyketides (2, 4-6, 8, 14, 16, and 17) together with eight known analogues (3, 7, 9-13, and 15) were isolated from the marine-derived fungus Aspergillus glaucus. The structures and stereochemistry of the new compounds were elucidated by spectroscopic and chemical methods, and their cytotoxicities were evaluated against the HL-60 and A-549 cell lines.
- Du, Lin,Zhu, Tianjiao,Liu, Hongbing,Fang, Yuchun,Zhu, Weiming,Gu, Qianqun
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experimental part
p. 1837 - 1842
(2009/09/06)
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- Dihydroxyacetone variants in the organocatalytic construction of carbohydrates: Mimicking tagatose and fuculose aldolases
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Dihydroxyacetone variants have been explored as donors in organocatalytic aldol reactions with various aldehyde and ketone acceptors. The protected form of dihydroxyacetone that was chosen for in-depth study was 2,2-dimethyl-1,3- dioxan-5-one, 1. Among the catalysts surveyed here, proline proved to be superior in terms of yield and stereoselectivities in the construction of various carbohydrate scaffolds. In a fashion analogous to aldolase enzymes, the de novo preparation of L-ribulose, L-lyxose, D-ribose, D-tagatose, 1-amino-1-deoxy-D-lyxitol, and other carbohydrates was accomplished via the use of 1 and proline. In reactions using 2,2-dimethyl-1,3-dioxan-5-one 1 as a donor, (S)-proline can be used as a functional mimic of tagatose aldolase, whereas (R)-proline can be regarded as an organocatalytic mimic of fuculose aldolase.
- Suri, Jeff T.,Mitsumori, Susumu,Albertshofer, Klaus,Tanaka, Fujie,Barbas III, Carlos F.
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p. 3822 - 3828
(2007/10/03)
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- Monosaccharide-H2O2 reactions as a source of glycolate and their stimulation by hydroxyl radicals
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An analysis of the H2O2-induced breakdown and transformation of different keto-monosaccharides at physiological concentrations reveals that glycolate and other short-chained carbohydrates and organic acids are produced. Depletion of monosaccharides and glycolate synthesis occurs at increased rates as the length of the carbohydrate chain is decreased, and is significantly increased in the presence of trace amounts of Fe2+ ions (10 μM). Rates of monosaccharide depletion (initial concentration of 3 mM) observed were up to 1.55 mmol h-1 in the case of fructose, and 2.59 mmol h-1 in the case of dihydroxyacetone, depending upon pH, H2O2 concentration, temperature and the presence or absence of catalytic amounts of Fe2+. Glycolate was produced by dihydroxyacetone cleavage at rates up to 0.45 mmol h-1 in the absence, and up to 1.88 mmol h-1 in the presence of Fe2+ ions (pH 8). Besides glycolate, other sugars (ribose, glyceraldehyde, glucose), glucitol (sorbitol) and organic acids (formic and 2-oxogluconic acid) were produced in such H2O2-induced reactions with fructose or dihydroxyacetone. EPR measurements demonstrated the participation of the {radical dot}OH radical, especially at higher pH. Presence of metal ions at higher pH values, resulting in increased glycolate synthesis, was accompanied by enhanced hydroxyl radical generation. Observed changes in intensity of DEPMPO-OH signals recorded from dihydroxyacetone and fructose reactions demonstrate a strong correlation with changes in glycolate yield, suggesting that {radical dot}OH radical formation enhances glycolate synthesis. The results presented suggest that different mechanisms are responsible for the cleavage or other reactions (isomerisation, auto- or free-radical-mediated oxidation) of keto-monosaccharides depending of experimental conditions.
- Maksimovi?, Vuk,Mojovi?, Milo?,Vu?ini?, ?eljko
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p. 2360 - 2369
(2007/10/03)
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- The effect of microwave irradiation on Mo(VI) catalyzed transformations of reducing saccharides
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Efficient microwave-assisted Mo(VI)-catalyzed transformations of the 10 most common aldoses are described. Both pentoses and hexoses were converted to the corresponding epimers in considerably shorter reaction times. The yields were comparable, or better compared to conventional synthetic methods.
- Hricoviniova, Zuzana
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p. 2131 - 2134
(2007/10/03)
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- Mitochondrially targeted antioxidants
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The invention provides mitochondrially targeted antioxidant compounds comprising a lipophilic cation moiety covalently coupled to a glutathione peroxidase mimetic. These compounds can be used to treat patients who would benefit from the reduction of oxidative stress.
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- Thioketals and thioethers for inhibiting the expression of VCAM-1
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Thioketals and thioethers are provided that inhibit the expression of VCAM-1, and which can be used in the treatment of VCAM-1 mediated diseases including inflammatory disorders, cardiovascular diseases, occular diseases, autoimmune diseases, neurological disorders, and cancer. The compounds also can be used to treat hyperlipidemia and/or hypercholesterolemia.
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- Prebiotic carbohydrate synthesis: Zinc-proline catalyzes direct aqueous aldol reactions of α-hydroxy aldehydes and ketones
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Zn-proline catalyzed aldolisation of glycoladehyde gave mainly tetroses whereas in the cross-aldolisation of glycoladehyde and rac-glyceraldehyde, pentoses accounted for 60% of the sugars formed with 20% of ribose. The Royal Society of Chemistry 2005.
- Kofoed, Jacob,Reymond, Jean-Louis,Darbre, Tamis
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p. 1850 - 1855
(2007/10/03)
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- Kinetic and chemical studies on the isomerization of monosaccharides in N-methylmorpholine-N-oxide (NMMO) under Lyocell conditions
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The Lyocell process is a modern and environmentally fully compatible industrial fiber-making technology. Cellulosic pulp is dissolved without chemical derivatization in a melt of N-methylmorpholine-N-oxide monohydrate (NMMO). In the present work, the reactions of monosaccharides under Lyocell conditions were investigated in detail, using capillary zone electrophoresis as the analytical technique to clarify the composition of reaction mixtures and to follow the kinetics. Under Lyocell conditions, xylose and glucose undergo two competitive reactions: rapid conversion to nonreducing products, and complete isomerization involving the whole carbohydrate backbone, via ketose intermediates. Sugar acids are present in minor amounts only, as demonstrated by employing isotopically labeled material for NMR techniques.
- Adorjan, Immanuel,Sjoeberg, John,Rosenau, Thomas,Hofinger, Andreas,Kosma, Paul
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p. 1899 - 1906
(2007/10/03)
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- Reactivity of γ-benzyloxyallyltins with cyclohexylidene glyceraldehydes
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Benzyloxyallyltributyltins were obtained in 50-80% yield by SN2′ reaction of alkyl-cyanocuprates with 3,3-dibenzyloxy-1-tributylstannylprop-1-ene in the presence of boron trifluoride. They reacted with cyclohexylidene glyceraldehyde in the presence of different Lewis acids and the obtained diastereomeric adducts were unambiguously identified after an ozonolysis/deprotection sequence by comparison with authentic aldopentoses. The mechanisms are briefly discussed as well as the relationship of the configuration of the reagents to the selectivity of the allylstannation reaction.
- Fliegel, Florian,Beaudet, Isabelle,Quintard, Jean-Paul
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p. 383 - 387
(2007/10/03)
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- Methods for treating plants and enhancing plant growth using polyacylglycosides and/or polyalkylglycosides and formulations for same
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Methods and formulations for treating plants and enhancing plant growth and for safening high concentrations of one or more phytocatalysts, wherein one or more formulations, comprising, a high concentration of one or more phytocatalysts, and an effective amount of one or more polyacylglycosides and polyalkylglycosides; and isomers, and metabolites, salts, hydrates, esters, amines, and derivatives of the polyacylglycosides and polyalkylglycosides, and combinations thereof, is applied to the plants.
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- Method for eliminating Staphylococcus aureus, novel microorganism of genus Brachybacterium, and care garment, care sheet or care bedclothes, each being immobilized with microorganism of genus Brachybacterium
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A method for eliminating Staphylococcus aureus is disclosed, including inoculating a microorganism of the genus Brachybacterium to Staphylococcus aureus to eliminate Staphylococcus aureus. A care garment, a care sheet or care bedclothes, each being immobilized with a microorganism or genus Brachybacterium, is also disclosed. One of the microorganismns of the genus Brachybacterium useful in the invention is novel and is deposited as a bacterial strain AAA-a of the genus Brachybacterium (Accession No. FERM BP-6848) in the International Depositary Authority for the deposit of microorganism.
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- A carbohydrate synthesis employing a photochemical decarbonylation
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A new route to the aldopentoses, ribose and lyxose, and the aldohexoses, talose and gulose, has been developed using chiral building blocks containing a bicyclo[3.2.1]octane framework by employing a photochemical decarbonylation reaction as the key step.
- Kadota, Kohei,Ogasawara, Kunio
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p. 8661 - 8664
(2007/10/03)
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- Methods of attaching conductive oligomers to electrodes
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The invention relates to nucleic acids covalently coupled to electrodes via conductive oligomers. More particularly, the invention is directed to the site-selective modification of nucleic acids with electron transfer moieties and electrodes to produce a new class of biomaterials, and to methods of making and using them.
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- Synthesis of racemic ribose from D-glucose
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Racemic ribose is a valuable starting material for investigations of the origins of biomolecular homochirality. It can be synthesized in seven steps starting from D-glucose.
- Miculka, Christian
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p. 948 - 950
(2007/10/03)
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- Ligands for MRI contrast agent
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Novel ligands for use in MRI contrast agents and which have the formula STR1 wherein R1 -R14, M , l, m, and n are defined herein.
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- Triazine compounds and methods of use therefor
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The present invention relates to compositions and methods for inhibiting nonenzymatic cross-linking (protein aging). Accordingly, a composition is disclosed which comprises a substituted 1,2,4-triazine of the formula (I) STR1 and the biologically and pharmaceutically acceptable salts thereof; capable of inhibiting the formation of advanced glycosylation endproducts of target proteins. The method comprises contacting the target protein with the composition. Both industrial and therapeutic applications for the invention are envisioned, as food spoilage and animal protein aging can be treated.
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- Bis-(2-aryl) hydrazones
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The present invention relates to compositions and methods for inhibiting nonenzymatic cross-linking (protein aging). Accordingly, a composition is disclosed which comprises a bis-(2-aryl)hydrazone capable of inhibiting the formation of advanced glycosylation endproducts of target proteins. The method comprises contacting the target protein with the composition. Both industrial and therapeutic applications for the invention are envisioned, as food spoilage and animal protein aging can be treated.
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