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This paper researches the compatibility of bamboo and Portland cement by measuring the hydration temperature of Portland cement. Meanwhile, bamboo shavings and Portland cement, which were utilized as main raw materials, were prepared into bamboo Portland cement particle boards through cold compression forming, so as to further verify the compatibility of bamboo and Portland cement and research the practicability of preparing bamboo Portland cement particle boards by using bamboo. Research studies show that bamboo contain water-soluble saccharides, such as polysaccharide, disaccharide, and glucose, and organic carboxylic acids, such as formic acid and acetic acid. Water-soluble saccharides are converted into saccharic acid after dissolving in water, then a saccharide–calcium complex with a pompon-like structure is formed through a reaction between saccharic acid and calcium ions of Portland cement hydrates, and the saccharide–calcium complex covers the surfaces of the cement particles and prevents further hydration of the cement, achieving a certain anticoagulation effect on Portland cement; a chelation reaction between the carboxyl of the organic carboxylic acid and the calcium ions of Portland cement hydrates takes place and the concentration of calcium ions in the hydration system is reduced, which exerts an influence on further hydration process of Portland cement and achieves a certain anticoagulation effect. Because of the poor compatibility of Portland cement and bamboo, the physical and mechanical properties of bamboo Portland cement particle boards prepared from bamboo shavings and Portland cement directly cannot meet the requirements of the national standards (GB/T24312-2009) of cement particle boards.

A new series of oxadiazole with thiadiazole moiety (6–27) were synthesized, characterized by different spectroscopic techniques and evaluated for β-glucuronidase inhibitory potential. Sixteen analogs such as 6, 7, 8, 9, 10, 12, 13, 14, 17, 18, 20, 23, 24, 25, 26 and 27 showed IC50 values in the range of 0.96 ± 0.01 to 46.46 ± 1.10 μM, and hence were found to have excellent inhibitory potential in comparison to standard d -saccharic acid 1,4-lactone (IC50 = 48.4 ± 1.25 μM). Two analogs such as 16 and 19 showed moderate inhibitory potential while analogs 11, 15, 21 and 22 were found inactive. Our study identifies new series of potent β-glucuronidase inhibitors for further investigation. Structure activity relationships were established for all compounds which showed that the activity is varied due to different substituents on benzene ring. The interaction of the compounds with enzyme active site were confirmed with the help of docking studies, which reveals that the electron withdrawing group and hydroxy group make the molecules more favorable for enzyme inhibition.

A novel method of coupling electrochemistry (EC) with mass spectrometry (MS) is illustrated with a paper-based electrochemical cell supported by carbon nanotubes (CNTs). The electrochemically formed ions, created at appropriate electrochemical potentials, are ejected into the gas phase from the modified paper, without the application of additional potential. The electrochemical cell was fabricated by using a rectangular CNT-coated Whatman 42 filter paper with printed electrodes, using silver paste. This was used for studying the electrochemical conversion of thiols to disulfides, and the functionalization of polycyclic aromatic hydrocarbons (PAHs), which involve S-S and C-C bond formations, respectively. We also demonstrate the versatility of the set-up by utilizing it for the detection of radical cations of metallocenes, monitoring the oxidation of sulfides through the detection of reactive intermediates, and the detection of radical cations of PAHs, all of which occur at specific applied potentials. Finally, the applicability of this technique for qualitative and quantitative analyses of environmentally relevant molecules has been demonstrated by studying the electrochemical oxidation of glucose (Glu) to gluconic acid (GlcA) and saccharic acid (SacA).

Phenolic compounds that are present in amaranth crops have gained a lot of interest from researchers due to their health benefits potential. Therefore, the aim of this study was to investigate phenolic compounds present in different plant parts of Amaranthuscruentus using liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry. Moreover, data were analyzed by one-way analysis of variance of the statistical analysis software, whereas commercial statistical package version 4.02 was used for principal component analysis. A total of 21 phenolic compounds were detected and eight were not identified. Caffeoylsaccharic acid isomer, coumaoryl saccharic acid, tryptophan, feruloyl-d-saccharic acid isomer a, b, and c, caffeoyl isocitrate, quercetin 3-O-rhamnosyl-rhamnosyl-glucoside, feruloyl isocitrate, hyperoside, kaempferol rutinoside, and alkaloid compounds were mostly detected in tender and mature leaves. Generally, rutin content was higher (p &lt, 0.05) in most vegetative parts of the amaranth plant, thus, late maturity leaves, tender leaves, and mature leaves, respectively. Lower quantities of rutin were observed in tender grains, flowers, and mature grains. It can be concluded that amaranth contains phenolic compounds, predominantly in the vegetative parts, which makes it to be a promising source of phenolic compounds beneficial to human health.

Novel sulfonamides having oxadiazole ring were synthesized by multistep reaction and evaluated to check in vitro β -glucuronidase inhibitory activity. Luckily, except compound 13 , all compounds were found to demonstrate good inhibitory activity in the range of IC 50 = 2.40 ± 0.01–58.06 ± 1.60 μM when compared to the standard d -saccharic acid 1,4-lactone (IC 50 = 48.4 ± 1.25 μM). Structure activity relationship was also presented. However, in order to ensure the SAR as well as the molecular interactions of compounds with the active site of enzyme, molecular docking studies on most active compounds 19 , 16 , 4 and 6 was carried out. All derivatives were fully characterized by 1 H NMR, 13 C NMR and EI-MS spectroscopic techniques. CHN analysis was also presented.

A series of N,N-diethyl phenyl thioxo-tetrahydropyrimidine carboxamide have been synthesized and investigated for their β-glucuronidase inhibitory activities. All molecules exhibited excellent inhibition with IC50 values ranging from 0.35 to 42.05 µM and found to be even more potent than the standard d -saccharic acid. Structure-activity relationship analysis indicated that the meta-aryl-substituted derivatives significantly influenced β-glucuronidase inhibitory activities while the para-substitution counterpart outperforming moderate potency. The most potent compound in this series was 4g bearing thiophene motif with IC50 of 0.35 ± 0.09 µM. To verify the SAR, molecular docking and molecular dynamics studies were also performed.

Sclerotinia sclerotiorum (S. sclerotiorum) is a soil-borne pathogen with broad host range. Dissolved organic matter (DOM) plays a vital role in regulating microbial activity in soil. Exogenous selenium (Se) inhibits plant pathogen growth and enhances the capacity of plants to resist disease. DOM from rape straw with Se treated in soil (RSDOMSe) was extracted, and the inhibitory effect on S. sclerotiorum growth was investigated. RSDOMSe inhibited S. sclerotiorum growth, which not only caused severe damage to S. sclerotiorum hyphae but also enhanced soluble protein leakage, thereby improving the growth inhibition ratio by 20.9%. As the action in intercellular, RSDOMSe led to a significant increase in oxalic acid and decrease in CWDE (cell wall-degrading enzyme, which helps pathogens to invade plants) activities, downregulation of Bi1 (BAX inhibitor-1, required for S. sclerotiorum virulence), Ggt1 (γ-glutamyl transpeptidase, regulates the ROS antioxidant system), CWDE2 and CWDE10 gene expression levels, compared with non-Se treated RSDOM (RSDOMN). Eight metabolites upregulated in RSDOMSe were identified by GC-TOF-MS, and among these metabolites, fumaric acid, maleic acid, malonic acid, mucic acid, saccharic acid, succunic acid and phenylacetic acid showed significant inhibition on S. sclerotiorum growth. These findings provide valuable insight into a new approach for developing eco-friendly fungicides.

Herein, we demonstrate rapid and complete photochemical detoxification of Cr(VI) by iron using saccharic acid (SA) as a sacrificial organic agent. 100% Cr(VI) (200 mu M) was reduced within 30 min using Fe(III) (50 mu M) and SA (300 mu M) under UV irradiation. The reaction mechanism involves photochemical recycling of Fe(III)/Fe(II) by SA via ligand to metal charge transfer (LMCT) along with the generation of a concomitant ligand radical and hydroperoxyl radical. Importantly, the MTT assay and gamma H2AX immunostaining were performed to evaluate the hitherto unexplored comparison of cytotoxicity and genotoxicity caused by untreated and treated aqueous Cr(VI). The results revealed that the Fe(III)/SA/UV treatment caused the complete removal of cytotoxic and genotoxic effects of Cr(VI) towards human cell lines. The presence of nitrate, chloride and natural organic matter increased the Cr(VI) reduction, while phosphate decreased the Cr(VI) reduction. Cu(II), Al(III) and Ni(II) had a positive effect on the Cr(VI) reduction. Furthermore, the Fe(III)/SA/UVC treatment caused almost complete Cr(VI) reduction in groundwater, lake water, and simulated galvanic wastewater. This study strongly supports the aptness of the Fe(III)/SA photochemical system for detoxification of Cr(VI) contaminated wastewater.

A library of novel 2,5-disubtituted-1,3,4-oxadiazoles with benzimidazole backbone (3a–3r) was synthesized and evaluated for their potential as β-glucuronidase inhibitors. Several compounds such as 3a–3d, 3e–3j, 3l–3o, 3q and 3r showed excellent inhibitory potentials much better than the standard (IC50 = 48.4 ± 1.25 μM: d -saccharic acid 1,4-lactone). All the synthesized compounds were characterized satisfactorily by using different spectroscopic methods. We further evaluated the interaction of the active compounds and the enzyme active site with the help of docking studies.

Due to the great biological importance of β-glucuronidase inhibitors, here in this study, we have synthesized a library of novel benzothiazole derivatives (1–30), characterized by different spectroscopic methods and evaluated for β-glucuronidase inhibitory potential. Among the series sixteen compounds i.e. 1–6, 8, 9, 11, 14, 15, 20–23 and 26 showed outstanding inhibitory potential with IC50 value ranging in between 16.50 ± 0.26 and 59.45 ± 1.12 when compared with standard d -Saccharic acid 1,4-lactone (48.4 ± 1.25 µM). Except compound 8 and 23 all active analogs showed better potential than the standard. Structure activity relationship has been established.

In this study synthesis and β -glucuronidase inhibitory potential of 3/5/8 sulfonamide and 8-sulfonate derivatives of quinoline ( 1–40 ) are discussed. Studies reveal that all the synthetic compounds were found to have good inhibitory activity against β -glucuronidase. Nonetheless, compounds 1 , 2 , 5 , 13 , and 22 – 24 having IC 50 values in the range of 1.60–8.40 μ M showed superior activity than the standard saccharic acid 1,4-lactone (IC 50 = 48.4 ± 1.25 μ M). Moreover, molecular docking studies of selected compounds were also performed to see interactions between active compounds and binding sites. Structures of all the synthetic compounds were confirmed through 1 H NMR, EI-MS and HREI-MS spectroscopic techniques.

Huanglongbing (HLB) is currently considered the most destructive disease of citrus. Since its spread to the Americas, HLB has killed millions of trees and caused a sharp decline in production in many citrus growing regions. With the continuous spread of HLB disease in Florida and worldwide, there is an urgent need for the development of commercial citrus cultivars with a strong tolerance to HLB. Interestingly, field observations showed that some of the recently released mandarin hybrids such as 'Sugar Belle' were tolerant to HLB. In this study, we investigated the volatile and non-volatile metabolites of greenhouse-grown 'Sugar Belle' mandarin and four of its ancestors in order to understand why 'Sugar Belle' mandarin is relatively tolerant to HLB. Leaf volatiles were directly extracted with hexane and analyzed using gas chromatography-mass spectrometry (GC-MS). Leaf polar metabolites were extracted with a mixture of methanol:water (1:1, v/v), derivatized to their trimethylsilyl ethers, and analyzed using GC-MS. Forty-seven volatile compounds and forty-two polar metabolites were detected in 'Sugar Belle' mandarin leaves and its ancestors. 'Sugar Belle' was high in several volatiles such as α-thujene, para-cymene, γ-terpinene, thymol, β-elemene, and (E)-β-caryophyllene. Some of these volatiles, especially thymol, β-elemene, and (E)-β-caryophyllene are known for their anti-microbial activity. In addition, 'Sugar Belle' mandarin was the highest in synephrine, benzoic acid, ferulic acid, caffeic acid, chiro-inositol, fructose, glucose, threonic acid, saccharic acid, and galactaric acid, and the second in threonine, malic acid, and myo-inositol compared to the ancestors. Phenolic compounds such as benzoic, ferulic, and caffeic acids may act as antibacterial agents, whereas others like sugar alcohols may protect 'Sugar Belle' mandarin from stress during pathogen attack. The tolerance of 'Sugar Belle' and other newly released mandarin hybrids should be further evaluated using greenhouse controlled studies. If tolerance of these hybrids is confirmed, they could be used to replace the traditionally susceptible cultivars.

2-Arylquinazolin-4(3H)-ones 1–25 were synthesized by reacting anthranilamide with various benzaldehydes using CuCl2·2H2O as a catalyst in ethanol under reflux. Synthetic 2-arylquinazolin-4(3H)-ones 1–25 were evaluated for their β-glucuronidase inhibitory potential. A trend of inhibition IC50 against the enzyme in the range of 0.6–198.2 μM, was observed and compared with the standard d -saccharic acid 1,4-lactone (IC50 = 45.75 ± 2.16 μM). Compounds 13, 19, 4, 12, 14, 22, 23, 25, 15, 8, 17, 11, 21, 1, 3, 18, 9, 2, and 24 with the IC50 values within the range of 0.6–44.0 μM, indicated that the compounds have superior activity than the standard. The compounds showed no cytotoxic effects against PC-3 cells. A structure–activity relationship is established.

Saccharides have been recognized as potential bio-lubricants because of their good hydration ability. However, the interfacial structures of saccharides and their derivatives are rarely studied and the molecular details of interaction mechanisms have not been well understood. In this paper, the supramolecular assembly structures of saccharic acids (including galactaric acid and lactobionic acid), mediated by hydrogen bonds O–H⋯N and O–H⋯O, were successfully constructed on a highly oriented pyrolytic graphite (HOPG) surface by introducing pyridine modulators and were explicitly revealed by using scanning tunneling microscopy (STM). Furthermore, friction forces were measured in the saccharic acid/pyridine co-assembled system by atomic force microscopy (AFM), revealing a larger value than a pristine saccharic acid system, which could be attributed to the stronger tip-assembled molecule interactions that lead to the higher potential energy barrier needed to overcome. The effort on saccharide-related supramolecular self-assembly and nanotribological behavior could provide a novel and promising pathway to explore the interaction mechanisms underlying friction and reveal the structure–property relationship at the molecular level.

Current research is based on the synthesis of novel ( E )-4-aryl-2-(2-(pyren-1-ylmethylene)hydrazinyl)thiazole derivatives ( 3 – 15 ) by adopting two steps route. First step was the condensation between the pyrene-1-carbaldehyde ( 1 ) with the thiosemicarbazide to afford pyrene-1-thiosemicarbazone intermediate ( 2 ). While in second step, cyclization between the intermediate ( 2 ) and phenacyl bromide derivatives or 2-bromo ethyl acetate was carried out. Synthetic derivatives were structurally characterized by spectroscopic techniques such as EI-MS, 1 H NMR and 13 C NMR. Stereochemistry of the iminic double bond was confirmed by NOESY analysis. All pure compounds 2 – 15 were subjected for in vitro β -glucuronidase inhibitory activity. All molecules were exhibited excellent inhibition in the range of IC 50 = 3.10 ± 0.10–40.10 ± 0.90 μM and found to be even more potent than the standard d -saccharic acid 1,4-lactone (IC 50 = 48.38 ± 1.05 μM). Molecular docking studies were carried out to verify the structure-activity relationship. A good correlation was perceived between the docking study and biological evaluation of active compounds.

We have chosen rice as a model crop to ascertain endogenous β-glucuronidase (family 79) activity and to differentiate the same from Escherichia coli based β-glucuronidase (family-2). The investigation dwells on characterizing endogenous β-glucuronidase (GUS) activity during the early stages of seed germination and from rice callus. Also, similar studies were made from homozygous transgenic rice line expressing E. coli GUS under the control of glyoxalase I promoter. Endogenous GUS activity was detected in plumules, shoots and calli of rice, nevertheless, showing differential response to pH. Further, endogenous GUS in rice was specifically inhibited by saccharic acid 1,4-lactone (SL) but, the E. coli β-glucuronidase remain unaffected, indicating distinct biochemical properties of family-2 and family-79 β-glucuronidase. Key words: Family 2, family 79, X-gluc, saccharic acid, 1,4-lactone.

Chiral metal-organic coordination polymers [Co2(sacch)2]·1/2H2O·CH3OH (1), [Cu(sacch)(H2O)2]·3H2O (2), and [Mg(H2O)3(sacch)] (3) (H2sacch is d-saccharic acid) were synthesized from aqueous or water-methanol solutions of potassium hydrogen saccharate and a salt of the corresponding metal. The compositions and structures of the resulting compounds were determined by single-crystal X-ray diffraction and confirmed by X-ray powder diffraction, IR spectroscopy, thermogravimetry, and elemental analysis.

Current study is based on the biology-oriented drug synthesis (BIODS) of 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl aryl carboxylate derivatives 1–26, by treating metronidazole with different aryl and hetero-aryl carboxylic acids in the presence of 1,1′-carbonyl diimidazole (CDI) as a coupling agent. Structures of all synthetic derivatives were confirmed with the help of various spectroscopic techniques such as EI-MS, 1H -NMR and 13C NMR. CHN elemental analyses were also found in agreement with the calculated values. Synthetic derivatives were evaluated to check their β-glucuronidase inhibitory activity which revealed that except few derivatives, all demonstrated good inhibition in the range of IC50 = 1.20 ± 0.01–60.30 ± 1.40 μM as compared to the standard d -saccharic acid 1,4-lactone (IC50 = 48.38 ± 1.05 μM). Compounds 1, 3, 4, 6, 9–19, and 21–24 were found to be potent analogs and showed superior activity than standard. Limited structure-activity relationship is suggested that the molecules having electron withdrawing groups like NO2, F, Cl, and Br, were displayed better activity than the compounds with electron donating groups such as Me, OMe and BuO. To verify these interpretations, in silico study was also performed, a good correlation was observed between bioactivities and docking studies.

The identification of iron chelates that can enhance photo-Fenton degradation is of great interest in the field of advanced oxidation process. Saccharic acid (SA) is a polyhydroxy carboxylic acid and completely non-toxic. Importantly, it can effectively bind Fe(III) as well as induce photoreduction of Fe(III). Despite having these interesting properties, the effect of SA on photo-Fenton degradation has not been studied. Herein, we demonstrate the first assessment of SA as an iron chelate in photo-Fenton process using methylene blue (MB) as a model organic contaminant. Our results demonstrate that SA has the ability to (i) enhance the photo-Fenton degradation of MB by about 11 times at pH 4.5 (ii) intensify photochemical reduction of Fe(III) to Fe(II) by about 17 times and (iii) accelerate the rate of consumption of H2O2 in photo-Fenton process by about 5 times (iv) increase the TOC reduction by about 2 times and (v) improve the photo-Fenton degradation of MB in the presence of a variety of common inorganic ions and organic matter. The influential properties of SA on photo-Fenton degradation is attributed to the efficient photochemical reduction of Fe(III) via LMCT (ligand to metal charge transfer reaction) to Fe(II), which then activated H2O2 to generate OH center dot and accelerated photo-Fenton degradation efficiency. Moreover, the effect of operational parameters such as oxidant: contaminant (H2O2: MB) ratio, catalyst: contaminant (Fe(III)SA: MB) ratio, Fe(III): SA stoichiometry and pH on the degradation of MB by photo-Fenton in the presence of SA is demonstrated. Importantly, SA assisted photo-Fenton caused effective degradation of MB and 4-Chiorophenol under natural sunlight irradiation in natural water matrix. The findings strongly support SA as a deserving iron chelate to enhance photo-Fenton degradation. (C) 2016 Elsevier Ltd. All rights reserved.

Thiadiazole derivatives 1–24 were synthesized via a single step reaction and screened for in vitro β-glucuronidase inhibitory activity. All the synthetic compounds displayed good inhibitory activity in the range of IC50 = 2.16 ± 0.01–58.06 ± 1.60 μM as compare to standard d -saccharic acid 1,4-lactone (IC50 = 48.4 ± 1.25 μM). Molecular docking study was conducted in order to establish the structure–activity relationship (SAR) which demonstrated that thiadiazole as well as both aryl moieties (aryl and N-aryl) involved to exhibit the inhibitory potential. All the synthetic compounds were characterized by spectroscopic techniques 1H, 13C NMR, and EIMS.

Benzothiazole derivatives 1 – 26 have been synthesized and their in vitro β-glucuronidase potential has been evaluated. Compounds 4 (IC 50 = 8.9 ± 0.25 μM), 5 (IC 50 = 36.1 ± 1.80 μM), 8 (IC 50 = 8.9 ± 0.38 μM), 13 (IC 50 = 19.4 ± 1.00 μM), 16 (IC 50 = 4.23 ± 0.054 μM), and 18 (IC 50 = 2.26 ± 0.06 μM) showed β-glucuronidase activity potent than the standard ( d -saccharic acid 1,4-lactone, IC 50 = 48.4 ± 1.25 μM). Compound 9 (IC 50 = 94.0 ± 4.16 μM) is found to be the least active among the series. All active analogs were also evaluated for cytotoxicity and none of the compounds showed any cytotoxic effect. Furthermore, molecular docking studies were performed using the gold 3.0 program to investigate the binding mode of benzothiazole derivatives. This study identifies a novel class of β-glucuronidase inhibitors.

Two chiral K(I) complexes based on d -saccharic acid (H2sac), [K(Hsac)]n (1) and [K2(sac)]n (2) were obtained from acidic and alkaline solution. The 3D framework of 1 includes K(I) polyhedral rods and typical pairwise coaxial right- and left-handed helical chains, and displays binodal 6-connected pcu topology. 2 contains 2D polyhedral sheets consisting of left-handed helical chains, and generates 3D network with an unprecedented (7,11)-connected net. Cyclic voltammetry tests and charge–discharge tests indicate that the addition of complex 2 to the electrolyte could improve the electrochemical properties of the nickel hydroxide electrode.

A chiral helical MOF [Mn2(sac)2(H2O)2]·3.3H2O (H2sac = d -saccharic acid) (1) has been synthesized and characterized. MOF 1 crystallizes in orthorhombic system with space group P212121, and the structure contains right-handed 21 helical chains in three directions with hydrophilic channels. From the topological point of view, the framework of MOF 1 can be abstracted as an unusual binodal 3-connected network with utg topology. The electrochemical property has been studied, undergoing two one-electron redox processes.

Salmonella enterica is a zoonotic pathogen of clinical and veterinary significance, with over 2500 serovars. In previous work we compared two serovars displaying host associations inferred from isolation statistics. Here, to validate genome sequence data and to expand on the role of environmental metabolite constitution in host range determination we use a phenotypic microarray approach to assess the ability of these serovars to metabolise ~500 substrates at 25°C with oxygen (aerobic conditions) to represent the ex vivo environment and at 37°C with and without oxygen (aerobic/anaerobic conditions) to represent the in vivo environment. A total of 26 substrates elicited a significant difference in the rate of metabolism of which only one, D-galactonic acid-g-lactone, could be explained by the presence (S. Mbandaka) or the absence (S. Derby) of metabolic genes. We find that S. Mbandaka respires more efficiently at ambient temperatures and under aerobic conditions on 18 substrates including: glucosominic acid, saccharic acid, trehalose, fumaric acid, maltotriose, N-acetyl-D-glucosamine, N-acetyl-beta-D-mannosamine, fucose, L-serine and dihydroxy-acetone; whereas S. Derby is more metabolically competent anaerobically at 37°C for dipeptides, glutamine-glutamine, alanine-lysine, asparagine-glutamine and nitrogen sources glycine and nitrite. We conclude that the specific phenotype cannot be reliably predicted from the presence of metabolic genes directly relating to the metabolic pathways under study.

A series of 15 novel compounds incorporating the thieno[2,3- b ]thiophene moiety were synthesized. The chemical structures of these compounds were deduced from elemental analyses, 1 H NMR, 13 C NMR, and ESI-mass spectral data. The enzyme inhibition potential of these compounds was evaluated, in vitro, against β-glucuronidase, xanthine oxidase, and α-chymotrypsin enzymes. The cytotoxicity was evaluated by a cell viability assay utilizing the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) dye. Among the compounds tested, compound 3 was the most potent β-glucuronidase inhibitor with an IC 50 value of 0.9 ± 0.0138 μM; it was much more active than the standard, d -saccharic acid 1,4-lactone (IC 50 = 45.75 ± 2.16 μM). Compound 12 , on the other hand, was the most potent as a xanthine oxidase inhibitor with an IC 50 of 14.4 ± 1.2 μM. With the characterization of their mechanism of action and with further testing, these compounds could be useful candidates as anticancer drugs. In addition, the newly synthesized compounds were subjected to POM analyses to get insights about their degree of their toxicity.

We focused on the changes of metabolite profiles in navel orange plants under long-term boron (B) deficiency using a gas chromatography-mass spectrometry (GC-MS) approach. Curling of the leaves and leaf chlorosis were observed only in the upper leaves (present before start of the treatment) of B-deficient plants, while the lower leaves (grown during treatment) did not show any visible symptoms. The metabolites with up-accumulation in B-deficient leaves were mainly proline, l-ornithine, lysine, glucoheptonic acid, fucose, fumarate, oxalate, quinate, myo-inositol and allo-inositol, while the metabolites with down-accumulation in B-deficient leaves were mainly serine, asparagine, saccharic acid, citrate, succinate, shikimate and phytol. The levels of glucose and fructose were increased only in the upper leaves by B deficiency, while starch content was increased in all the leaves and in roots. The increased levels of malate, ribitol, gluconic acid and glyceric acid occurred only in the lower leaves of B-deficient plants. The increased levels of phenols only in the upper leaves indicated that the effects of B on phenol metabolism in citrus plants may be a consequence of disruptions in leaf structure. Metabolites with opposite reactions in upper and lower leaves were mainly glutamine, glycine and pyrrole-2-carboxylic acid. To our knowledge, the phenomena of allo-inositol even higher than myo-inositol occurred characterized for the first time in this species. These results suggested that the altered pattern of central metabolism may be either specific or adaptive responses of navel orange plants to B deficiency.

The migration of uranium through siliceous porous media has been investigated by conducting a series of core flood experiments in conjunction with the development of predictive coupled chemical transport models. Initial investigations made during the programme have demonstrated that under oxidising conditions, at pH≈5–6 with NaCl concentrations ≈0.3 mol dm−3, uranium is strongly retarded by adsorption to a Clashach Sandstone matrix. Sorption has been shown to be largely reversible, dependent on the absolute concentrations involved and on the finite sorptive capacity of the rock. Comparative experimental and modelling studies have also demonstrated the sorptive behaviour of the Clashach Sandstone to be close to that of amorphous silica. Recent work has focused on assessing the role of EDTA and cellulose degradation products in enhancing uranium mobility by complexation/chelation. Laboratory scale migration experiments involving radio-labelled EDTA and saccharic acid have been supported by batch sorption studies to investigate the behaviour of the U–EDTA-silica and U–saccharic acid-silica systems. In order to obtain unequivocal comparisons of the rates of uranium migration in the presence and absence of the organic complexant, parallel column floods have been carried out such that intact cores of Clashach Sandstone have been flooded with waters from the same reservoirs at carefully controlled flow rates. Geochemical modelling techniques have been used to assess the chemical speciation of the waters, to describe the sorption behaviour observed in the batch sorption studies and, where appropriate, derive model specific data to allow predictive coupled chemical transport modelling of the migration experiments. It is shown that, for a pre-equilibrated uranium-organic system, the use of conventional techniques encompassing complexation in the aqueous phase and reversible adsorption of organically-bound species would give a reasonable approximation of the system. Conversely, where uranium is introduced ahead of the organic plume, re-mobilisation is severely constrained by slow desorption kinetics. The results point to the need to consider the sequence of radionuclide interactions with organic waste components in formulating models used in performance assessment.

Bisindole analogs 1–17 were synthesized and evaluated for their in vitro β-glucuronidase inhibitory potential. Out of seventeen compounds, the analog 1 (IC50 = 1.62 ± 0.04 μM), 6 (IC50 = 1.86 ± 0.05 μM), 10 (IC50 = 2.80 ± 0.29 μM), 9 (IC50 = 3.10 ± 0.28 μM), 14 (IC50 = 4.30 ± 0.08 μM), 2 (IC50 = 18.40 ± 0.09 μM), 19 (IC50 = 19.90 ± 1.05 μM), 4 (IC50 = 20.90 ± 0.62 μM), 7 (IC50 = 21.50 ± 0.77 μM), and 3 (IC50 = 22.30 ± 0.02 μM) showed superior β-glucuronidase inhibitory activity than the standard ( d -saccharic acid 1,4-lactone, IC50 = 48.40 ± 1.25 μM). In addition, molecular docking studies were performed to investigate the binding interactions of bisindole derivatives with the enzyme. This study has identified a new class of potent β-glucouronidase inhibitors.

Polyaddition of saccharic acid dilactones prepared from D-glucose and D-mannitol, D-glucaro-, and D-mannaro-1,4 :6,3-dilactones (1 and 2, respectively), with hexamethylene diisocyanate (3a) and methyl (S)-2,6-diisocyanatocaproate (3b) was carried out by using dibutyltin dilaurate as a catalyst at 50, 25, and 0°C to give polyurethanes (4 and 5) having dilactone moieties in the main chains. The resulting polymers were found to decompose easily in phosphate buffers under neutral or slightly basic conditions (pH 7 or 8). Therefore, the polyurethanes may be used as novel degradable polymeric materials.

A microdetermination of propranolol enantiomers and of their glucuronide and sulphate conjugates in human plasma and urine by reversed-phase HPLC after chiral derivatization is described. After extraction from 100 μl of plasma or urine with racemic 4-methylpropranolol as internal standard (I.S.), the enantiomers are derivatized with R(+)-phenylethylisocyanate as chiral derivatization reagent. Chromatography is performed on Novapak C 18 column with fluorescence detection. Glucuronide and sulphate conjugates are cleaved prior to extraction by incubating, respectively, the samples with glucuronidase—arylsulphatase and saccharic acid 1–4 lactone as specific glucuronidase inhibitor. The retention times of propranolol and I.S. enantiomer derivatives are short ( t R = 5.5–6.2 min and 8.8–10.1 min, respectively). The diastereomeric derivatives are very stable and show good peak symmetry and resolutions ( R S = 2 and 2.2). The use of 4-methylpropranolol as I.S. improves significantly relative standard deviations (RSD: 1.7–5.1). Sensitivity is about 1 ng ml −1 per enantiomer. The method is applied to pharmacokinetic studies of racemic propranolol in human plasma and urine. S-propranolol and its conjugates show higher concentrations than R-propranolol and its conjugates in plasma and urine.

Ring-opening polyaddition of a saccharic acid dilactone prepared from D-glucose, D-glucaro-1,4 : 6,3-dilactone, with several alkylenediamines proceeded at room temperature with no catalyst. The resulting new polyamides carrying many pendant hydroxyl groups, poly(alkylene D-glucaramide)s, were more amorphous and hydrophilic than the corresponding nylons having no hydroxyl groups, and were hydrolyzed more easily than the latter in an acidic condition. The ring-opening ability of D-mannaro-1,4:6,3-dilactone, which was another saccharic acid dilactone obtained from D-mannitol, was found to be lower than that of the D-glucaric analogue. © 1993 John Wiley & Sons, Inc.

The comparative acute cytotoxicities were determined for a varied spectrum of minor dietary non-nutrients that have been implicated as chemopreventive agents. Cytotoxicity was determined with the neutral red (NR) assay, using BALB/c mouse 3T3 fibroblasts as the bioindicators. Based on midpoint cytotoxicity (NR50) values, the range of cytotoxicity for the different chemicals varied by 1000 times. The sequence of potency was tannic acid, tamoxifen citrate, quercetin, benzyl and phenethyl isothiocyanate>glycyrrhetinic acid>indole-3-carbinol>caffeic acid>phytic acid>vanillin>ellagic acid> d -saccharic acid 1,4-lactone. Vanillin, at slight to moderately toxic concentrations, was the only test agent that induced multinucleation in the 3T3 fibroblasts.

High-calcium soy milk was prepared by adding calcium gluconate as a calcium source, sodium hexametaphosphate (SHMP) as a sequestering agent, and calcium- D -saccharic acid as a stabilizing agent, so that the calcium content of soy milk was increased to the same or higher levels than that of bovine milk. It was demonstrated that the addition of these substances resulted in a soy milk with a high content of calcium and satisfactory heat stability of the final beverage. SHMP and calcium- D -saccharic acid were shown to be effective for reduction of the calcium ion activity of the soy milk. The findings suggest that there is a synergistic effect between the sequestering agent and the stabilizing agent.

To evaluate the ability of D-saccharic acid 1.4-lactone (SAL), a beta-glucuronidase inhibitor, to prevent irinotecan hydrochloride (CPT-11) from inducing mucosal damage as a cause of diarrhea in rats.Wistar rats were divided into six groups of three animals each, administered 1.0 ml isotonic solution intraperitoneally once daily for up to three consecutive days, respectively for up to six days. The series were as follows: (1) On days 1-3: saline; (2) On days 1-3: 200 mg CPT-11/m2; (3) On days -3 to -1 relative to the first administration of CPT-11: 10 mg/ml SAL; on days 1-3: 200 mg CPT-11/m2; (4) On days -3 to +3 relative to the first administration of CPT-11: 10 mg/ml SAL, and on days 1-3: additional 200 mg CPT-11/m2; (5) On days 1-3: 200 mg CPT-11/m2 (0.5 ml) + 10 mg/0.5 ml SAL; (6) On days -3 to -1 relative to the first administration of CPT-11: 3 mg/ml SAL, and on days 1-3: 200 mg CPT-11/m2. Luminal mucosa damage of the small intestine was detected by histology 24 h after the last intraperitoneal application. Peptidase activities of the proximal jejunum were measured by using an in situ perfusion model.Following intraperitoneal CPT-11 treatment, using conventional histology of paraffin sections, we observed severe mucosal damage. This was reflected by a decrease of the villi/crypt ratio, an increase of apoptotic cells, as well as an increase of mitotic figures in the crypt region. There was a concomitant increased lymphatic infiltration in mucosa of CPT-11 treated rats. This damage pattern could be clearly reduced by co-treatment with the beta-glucuronidase inhibitor, SAL, independent of the treatment schedule. In contrast to our expectations based on previous reports, the intraperitoneal application of CPT-11 alone or in combination with SAL did not cause significant differences in luminal enzyme liberation in comparison with controls in the in situ perfusion assay.The beta-glucuronidase inhibitor SAL is able to significantly reduce CPT-11-induced mucosal damage in the small intestine of rats. This observation might soon have a clinical impact for the treatment of patients with CPT-11.

The Al(III)-binding abilities of two aldaric acids, D-saccharic acid and mucic acid (the neutral form is denoted as H(2)L), were studied in solution by means of pH potentiometric, (1)H and (13)C NMR, and ESI-MS techniques. The most probable conformations and isomeric binding modes of the complexes formed in solution were determined by density functional theory (DFT) calculations. A solid D-saccharic acid complex K(2)[[Al(LH(-2))(H(2)O)](2)].H(2)O was isolated and crystallographically characterised. The two alcoholic hydroxy groups alpha to the terminal COO(-) groups were found to take part in the coordination, but in different ways. One of them coordinates in a bridging mode. Detailed ESI-MS and NMR studies proved that the complex retains its structure in solution. However, depending on the ligand and the pH, such complexes may exist in two isomeric forms. DFT calculations on the ion [[Al(LH(-2))(H(2)O)](2)](2-) revealed that several orbitals participate in stabilizing the dimeric arrangement.

We have evaluated the inhibition of testicular hyaluronidase and hyaluronan lyase by L-ascorbic acid and chemical analogs. We observed that L-ascorbic acid, D-isoascorbic acid and dehydroascorbic acid inhibited both types of enzymes, but showed stronger effects towards hyaluronan lyase. But these compounds were observed to degrade the substrate, hyaluronan, by themselves. Of the other ascorbic acid analogs tested, saccharic acid inhibited hyaluronan lyase, while not affecting the enzymatic activity of testicular hyaluronidase, nor affecting the physic-chemical stability of hyaluronan. This is the first compound, to our knowledge, to be shown to possess such selective inhibition. Therefore, we propose that saccharic acid could serve as a lead compound for the development of potent and selective inhibitors of bacterial hyaluronan lyase or of polysaccharide lyase enzymes in general as we observed this compound to be capable of inhibiting chondroitinase ABC in addition to hyaluronan lyase.

A fundamental understanding of aqueous silicate chemistry is a prerequisite to unraveling silicon's (Si) role in living systems. Owing primarily to the advent of 29Si nuclear magnetic resonance (NMR) spectroscopy, the depth of that understanding has increased dramatically over the past two decades. By comparison, details of the biochemistry of Si are sparse. Although several proteins and amino acids believed to be associated with silicates have been isolated, no organosilicon compounds have so far been identified under physiological conditions. Nevertheless, hypervalent Si complexes have very recently been shown to form in the presence of aliphatic polyols and polyol acids, such as mannitol and saccharic acid, respectively. Such simple aliphatic hydrocarbons may play a crucial role in the uptake, transport, and deposition of Si in nature. The objective of this paper is to provide an overview of the speciation, equilibria, and chemical exchange kinetics of Si in aqueous environments, along with an examination of applicable methods of chemical analysis.

We identified a rapid and novel system to effectively metabolize a large amount of H2O2 in the suspension cells of Scutellaria baicalensis Georgi. In response to an elicitor, the cells immediately initiate the hydrolysis of baicalein 7-O-beta-D-glucuronide by beta-glucuronidase, and the released baicalein is then quickly oxidized to 6,7-dehydrobaicalein by peroxidases. Hydrogen peroxide is effectively consumed during the peroxidase reaction. The beta-glucuronidase inhibitor, saccharic acid 1,4-lactone, significantly reduced the H2O2-metabolizing ability of the Scutellaria cells, indicating that beta-glucuronidase, which does not catalyze the H2O2 degradation, plays an important role in the H2O2 metabolism. As H2O2-metabolizing enzymes, we purified two peroxidases using ammonium sulfate precipitation followed by sequential chromatography on CM-cellulose and hydroxylapatite. Both peroxidases show high H2O2-metabolizing activity using baicalein, whereas other endogenous flavones are not substrates of the peroxidase reaction. Therefore, baicalein predominantly contributed to H2O2 metabolism. Because beta-glucuronidase, cell wall peroxidases, and baicalein pre-exist in Scutellaria cells, their constitutive presence enables the cells to rapidly induce the H2O2-metabolizing system.

Silymarin, a commercial crude drug used as a hepatoprotective, was found to inhibit 53% of beta-glucuronidase activity at a final concentration of 0.8 mg/ml. Of three compounds A, silybin and C, which were isolated from silymarin, A and silybin potently inhibited the enzyme activity, followed by C. beta-Glucuronidases of intestinal bacteria, HGU-1 and HGU-2, and E. coli HB101 were noncompetitively inhibited by silybin. beta-Glucuronidase of the feces of a healthy human and of a human with colon cancer were also inhibited by silybin, silymarin and saccharic acid 1,4-lactone at 0.03-0.15 mg/ml. Silymarin and silybin protected the increase in enzyme activity in the serum of the rats treated with CCl4.

The number of alkalotolerant intestinal bacteria was 1% of the total flora in humans and 0.8% of those in rats. The beta-glucosidase and beta-glucuronidase activity of these intestinal bacteria was induced by elevating the pH of the medium, but the growth was not changed. The enzyme activity in a medium of pH 7 was 5- to 10-fold higher than that in a medium of pH 6. Isolated bacteria from human and rat feces were cultured in a pH 5 general anaerobic medium (GAM) broth to reach a stationary phase, then the pH of the media was changed from 5 to 8. Both beta-glucosidase and beta-glucuronidase were increased 9.2-12.1-fold. The activity of these enzymes was also increased 2-16-fold by adding substrates (p-nitrophenyl-beta-D-glucuropyranoside or p-nitrophenyl-beta-D-glucuronide). beta-Glucuronidase(s) was inhibited by saccharic acid 1,4-lactone or D-glucuronic acid. However, when lactulose was added to the medium, and then intestinal microflora were inoculated in the medium, the productivity of these enzymes dramatically decreased. We thus contend that the induction of the beta-glucosidase and beta-glucuronidase of intestinal bacteria by a high pH can cause colorectal cancer.