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Background: Polycarboxylic acids are of interest as simple mimics for cellulase enzyme catalyzed depolymerization of cellulose. In this study, DFT calculations were used to investigate the effect of structure on dicarboxylic acid organo-catalyzed hydrolysis of cellulose model compound D-cellobiose to D-glucose. Methods: Binding energy of the complex formed between D-cellobiose and acid (Ebind), as well as glycosidic oxygen to dicarboxylic acid closest acidic H distance were studied as key parameters affecting the turn over frequency of hydrolysis in water. Result: α-D-cellobiose - dicarboxylic acid catalyst down face approach showed high Ebind values for five of the six acids studied; indicating the favorability of down face approach. Maleic, cis-1,2-cyclohexane dicarboxylic, and phthalic acids with the highest catalytic activities showed glycosidic oxygen to dicarboxylic acid acidic H distances 3.5-3.6 Å in the preferred configuration. Conclusion: The high catalytic activities of these acids may be due to the rigid structure, where acid groups are held in a fixed geometry.

Renewable resources based hydrovanilloin [1,2- bis(4-hydroxy-3-methoxyphenyl)-1,2-ethanediol] was synthesized in 86% yield by electrochemical dimerization of vanillin in aqueous NaOH. This symmetrical bis-phenol monomer was then used for the preparation of urethane polymers by two different methods. In the first method a 1:2 mole ratio mixture of hydrovanilloin and diisocyanate was polymerized in DMF using 1,4-diazabicyclo[2,2,2]octane as the catalyst at 60°C, for 1 h to give poly(hydrovanilloin–urethane)s. In the second method diisocyanates were first reacted with polyethylene glycol-400 to give pre-polymers. Then prepolymers were reacted with equivalent amount of hydrovanilloin at 60°C for 4 days to produce poly(hydrovanilloin-ethylene glycol-urethane)s. The first method resulted hard poly(hydrovanilloin–urethane)s showing Tg values in the range of 121–172°C. The second method yielded softer poly(hydrovanilloin-ethylene glycol-urethane)s and these polymers failed to show distinct glass transition temperatures in the DSC analysis. However, poly(hydrovanilloin-ethylene glycol-urethane)s showed better thermal stabilities than polymers without polyethylene glycol units.

A novel route to graphene oxide (GO) is presented where the cellulosic biofilm formed at the air–water interface as a waste product in the kombucha tea beverage fermentation industry is used as the renewable carbon source. A kombucha pellicle was first purified by treatment with 1.0 mol/L aqueous NaOH at 90 °C and bleaching with 1.5% (w/w) aqueous NaOCl at 23 °C and then pyrolyzed at 600–800 °C in air or under an inert atmosphere. The highest GO yield of 22.5% (w/w) was obtained by pyrolysis at 600 °C under Ar. The product was identified as GO using FT-IR, Raman, XPS, XRD, and scanning electron microscopy. The ability to transform to GO by simple pyrolysis may be due to an extraordinarily highly ordered arrangement of glucan chains in kombucha pellicle fibrils. This discovery provides the first sustainable feedstock-based, simple, green route to GO, without the use of concentrated strong acids and oxidizing agents used in current Hummers’ method.

The effects of a series of co-catalysts: iron(III)chloride, zinc chloride, sodium borate, acetic acid, oxalic acid, 10% Pd-C, sodium carbonate, and Raney-Ni as well as H2 at 200 psi reductive conditions were studied on the iron(0)-catalyzed hydrothermal liquefaction of switchgrass at 210 °C. The addition 10% (w/w) iron(III)chloride as a co-catalyst in 60% aq. ethanol, without a hydrogen atmosphere enhanced the liquefaction yield from 55.7 ± 1.5 to 67.6 ± 2.5%. The use of Pd/C (5% w/w) and Raney-Ni (5% w/w) as co-catalysts could also enhance the liquefaction yields to 67.0 ± 3.0 and 72.3 ± 1.8% respectively, in reactions carried out under hydrogen atmosphere at 200 psi, in H2O, 210 °C, 24 h. GC-MS analysis of the liquefaction products revealed that C5-C10 range partially oxygenated products are formed and the composition of the liquefaction product depends on the co-catalyst used. The thermogravimetric and FT-IR analysis of liquefaction residues indicated that polysaccharide fraction is mainly liquefied in these iron(0)-catalyzed liquefactions of switchgrass at 210 °C.

Zinc is an essential element for humans, and its deficiency was documented in 1963. Nutritional zinc deficiency is now known to affect over two billion subjects in the developing world. Conditioned deficiency of zinc in many diseases has also been observed. In zinc-deficient dwarfs from the Middle East, we reported growth retardation, delayed sexual development, susceptibility to infections, poor appetite, and mental lethargy. We never found a zinc-deficient dwarf who survived beyond the age of 25 y. In an experimental model of human mild zinc deficiency, we reported decreased thymulin (a thymopoietic hormone) activity in Th1 cells, decreased mRNAs of IL-2 and IFN-gamma genes, and decreased activity of natural killer cells (NK) and T cytotoxic T cells. The effect of zinc deficiency on thymulin activity and IL-2 mRNA was seen within eight to twelve weeks of the institution of zinc-deficient diet in human volunteers, whereas lymphocyte zinc decreased in 20 weeks and plasma zinc decreased in 24 weeks after instituting zinc-deficient diet. We hypothesized that decreased thymulin activity, which is known to proliferate Th1 cells, decreased the proliferation differentiation of Th1 cells. This resulted in decreased generation of IL-2 and IFN-gamma. We observed no effect in Th2 cell function; thus, zinc deficiency resulted in an imbalance of Th1 to Th2 function resulting in decreased cell-mediated immunity. Zinc therapy may be very useful in many chronic diseases. Zinc supplementation improves cell-mediated immunity, decreases oxidative stress, and decreases generation of chronic inflammatory cytokines in humans. Development of sensitive immunological biomarkers may be more sensitive than an assay of zinc in plasma and peripheral blood cells for diagnosis of marginal zinc deficiency in human.

Two chitosan silica hybrid materials were prepared by a two-step process in 78–84% yields using the homogeneous phase reaction of 3-(triethoxysilyl)propyl isocyanate with chitosan dissolved in 1-n-butyl-3-methylimidazolium chloride ionic liquid (∼10% w/w), which was followed by NH4OH catalyzed hydrolysis of triethoxysilyl groups and then sol-gel process. These new hybrid materials were shown to adsorb up to about 95% of Fe3+ from 5 × 10−4 M aqueous solution at room temperature in 24 h.

In the present work, combustion synthesis of ZnO nanoparticles using lemon juice and citric acid as fuels has been carried out. A comparative analysis of the obtained powders has been conducted to understand the strategic advantages of using lemon juice over citric acid as the combustion fuel for the synthesis of ZnO nanopartilcles. The X-ray diffractograms of both the samples revealed the presence of wurtzite hexagonal structure with the standard JCPDS pattern of zincite [36-1451] with varying crystallite sizes. Surface morphology of the samples was studied by scanning electron microscopy. Particle shapes and sizes were determined by transmission electron microscopy. Although wurtzite hexagonal structures were seen in both the synthesis methods, their morphology and sizes differed significantly with samples prepared by lemon juice presenting smaller size. The band gap energy value determined by Wood-Tauc method was found to be ~ 3.2 eV for both the samples. DPPH assay revealed the antioxidant activity of the samples at varied concentrations. Further, antimicrobial studies were greater for those prepared by lemon juice. Furthermore, trypan blue and MTT assay evaluation of nanoparticles against PC-3, HCT116, A549, and MDA-MB-231 cancer cell lines indicated enhanced anticancer activity of ZnO nanoparticles prepared by lemon juice. It was found that the sample prepared using lemon juice exhibited IC50 values of 78.80 μg/mL, 28.75 μg/mL, and 10.7 μg/mL, whereas the sample prepared using citric acid as fuel exhibited IC50 values of 103.6 μg/mL, 41.52 μg/mL, and 20.06 μg/mL, towards PC-3, HCT 116, and MDA-MB-231 respectively.

The degradation of cellulose was studied using 1-(3-propylsulfonic)-3-methylimidazolium chloride and 1-(4-butylsulfonic)-3-methylimidazolium chloride acidic ionic liquids as catalysts in acetone at 120 °C for 3.5 h. The products were analyzed using LC-MS with a C18 column and 0.1% formic acid in water - methanol as the eluent solvent. Eleven cellulose degradation products were identified in the furanic biocrude formed using mass spectroscopy. The identified compounds include: 5-hydroxymethylfurfural (HMF), seven products formed from aldol condensation of HMF with one to three acetone molecules, one furfural-acetone aldol product and two HMF ether products. The percent conversions of cellulose to the furanic biocrude product for the two catalysts 1-(3-proylsulfonic)-3-methylimidazolium chloride and 1-(4-butylsulfonic)-3-methylimidazolium chloride were 25.7 and 19.3% respectively.

This study was carried out to determine the influence of cuprous oxide nanoparticles (Cu2O NPs) biosynthesised from leaf extracts of Flacourtia montana on the tomato Lycioersicum esculentum seed germination, seedling growth and vigour index. Here we examined the promotory and phytotoxic effect of Cu2O NPs (0-160ppm) on tomato seeds resulted in dosage dependent response. The highest germination percentage (95%) was observed at 20ppm Cu2O NPs, however, above 20ppm Cu2O NPs, there is a reduction in the seed germination. The tomato seedlings showed increased root and shoot elongation up to 20ppm Cu2O NPs concentration, further increase in NPs concentration caused the negative effect on plants growth and development. The leaf pigments showed increasing trend in tomato plants after treatment with Cu2O NPs up to 20ppm as compared to control. Phytotoxicity of Cu2O NPs in tomato seedlings demonstrated by lower contents of chlorophyll a, b and carotenoid pigments. The study of effect on antioxidant enzymes showed increases in activity with increase in Cu2O NPs concentration for two enzymes, Super oxide dismutase (SOD) and Glutathione Peroxidase (GPX) out of five enzymes treated. High antioxidant activity of enzymes is followed by the increased lipid peroxidation and decrease in free radical scavenging activity by the DPPH. The activity of Catalase, Pheny Alanine Aminolyase and Poly Phenol Oxidase enzymes were found to increase up to 20ppm as compared to control and above this, all three enzymes showed decrease in activity. Uptake of Cu2O NPs nanoparticle by tomato seedlings was confirmed by atomic absorption spectroscopy. Key words: Nano-Cuprous Oxide, Flacourtia montana, Tomato, antioxidant enzymes, lipid peroxidation

Limiting dysfunctional neutrophilic inflammation while preserving effective immunity requires a better understanding of the processes that dictate neutrophil function in the tissues. Quantitative mass-spectrometry identified how inflammatory murine neutrophils regulated expression of cell surface receptors, signal transduction networks, and metabolic machinery to shape neutrophil phenotypes in response to hypoxia. Through the tracing of labeled amino acids into metabolic enzymes, proinflammatory mediators, and granule proteins, we demonstrated that ongoing protein synthesis shapes the neutrophil proteome. To maintain energy supplies in the tissues, neutrophils consumed extracellular proteins to fuel central carbon metabolism. The physiological stresses of hypoxia and hypoglycemia, characteristic of inflamed tissues, promoted this extracellular protein scavenging with activation of the lysosomal compartment, further driving exploitation of the protein-rich inflammatory milieu. This study provides a comprehensive map of neutrophil proteomes, analysis of which has led to the identification of active catabolic and anabolic pathways that enable neutrophils to sustain synthetic and effector functions in the tissues. ispartof: JOURNAL OF CLINICAL INVESTIGATION vol:131 issue:10 ispartof: location:United States status: published

Summary Neutrophils can function and survive in injured and infected tissues, where oxygen and metabolic substrates are limited. Using radioactive flux assays and LC-MS tracing with U-13C glucose, glutamine, and pyruvate, we observe that neutrophils require the generation of intracellular glycogen stores by gluconeogenesis and glycogenesis for effective survival and bacterial killing. These metabolic adaptations are dynamic, with net increases in glycogen stores observed following LPS challenge or altitude-induced hypoxia. Neutrophils from patients with chronic obstructive pulmonary disease have reduced glycogen cycling, resulting in impaired function. Metabolic specialization of neutrophils may therefore underpin disease pathology and allow selective therapeutic targeting., Graphical Abstract, Highlights • Neutrophils utilize gluconeogenesis (GNG) to generate glycogen stores • Glycogenesis is essential for neutrophil survival and function • Defective glycogen cycling impairs neutrophil function in COPD • Glycogen cycling underpins the metabolic specialization of neutrophils, Neutrophils are required to meet their energy demands at inflamed sites where nutrients may be limited. Sadiku et al. provide evidence of a specialized metabolism that enables neutrophils to utilize glycogen cycling for energy production. This is essential for neutrophil function and survival, and dysregulation is associated with chronic disease states.

Background Human kidney stones form via repeated events of mineral precipitation, partial dissolution, and reprecipitation, which are directly analogous to similar processes in other natural and manmade environments, where resident microbiomes strongly influence biomineralization. High-resolution microscopy and high-fidelity metagenomic (microscopy-to-omics) analyses, applicable to all forms of biomineralization, have been applied to assemble definitive evidence of in vivo microbiome entombment during urolithiasis. Methods Stone fragments were collected from a randomly chosen cohort of 20 patients using standard percutaneous nephrolithotomy (PCNL). Fourier transform infrared (FTIR) spectroscopy indicated that 18 of these patients were calcium oxalate (CaOx) stone formers, whereas one patient formed each formed brushite and struvite stones. This apportionment is consistent with global stone mineralogy distributions. Stone fragments from seven of these 20 patients (five CaOx, one brushite, and one struvite) were thin sectioned and analyzed using brightfield (BF), polarization (POL), confocal, super-resolution autofluorescence (SRAF), and Raman techniques. DNA from remaining fragments, grouped according to each of the 20 patients, were analyzed with amplicon sequencing of 16S rRNA gene sequences (V1–V3, V3–V5) and internal transcribed spacer (ITS1, ITS2) regions. Results Bulk-entombed DNA was sequenced from stone fragments in 11 of the 18 patients who formed CaOx stones, and the patients who formed brushite and struvite stones. These analyses confirmed the presence of an entombed low-diversity community of bacteria and fungi, including Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, and Aspergillus niger. Bacterial cells approximately 1 μm in diameter were also optically observed to be entombed and well preserved in amorphous hydroxyapatite spherules and fans of needle-like crystals of brushite and struvite. Conclusions These results indicate a microbiome is entombed during in vivo CaOx stone formation. Similar processes are implied for brushite and struvite stones. This evidence lays the groundwork for future in vitro and in vivo experimentation to determine how the microbiome may actively and/or passively influence kidney stone biomineralization.

The essential role of zinc in human health was first suggested by our studies in growth-retarded Iranian villagers in 1961. Our later studies in 1963 established conclusively that zinc was essential for human and that zinc deficiency resulted in severe growth retardation, hypogonadism in males, immune dysfunctions, and cognitive function impairment. The suggestion that zinc was an essential element for humans remained very controversial, but in 1974, the USA National Academy of Sciences declared zinc as an essential element for humans and established the recommended dietary allowances. In 1978, the FDA and other regulatory agencies made it mandatory to include zinc in total parenteral nutrition fluids, which resulted in saving many lives. During the past five decades, tremendous progress has been made in the understanding of the biochemical role of zinc, and we now know that zinc therapy has impacted significantly on human health and diseases. In this review, I plan to present a brief historical review of the discovery of zinc as an essential element for humans, the clinical manifestations of zinc deficiency, its therapeutic impact on human health and diseases, biomarkers of human zinc deficiency, and its biochemical role.

We performed a review of the environmental surveillance methods commonly used to collect and concentrate poliovirus (PV) from water samples. We compared the sampling approaches (trap vs grab), the process methods (precipitation vs filtration), and the various tools and chemical reagents used to separate PV from other viruses and pathogens in water samples (microporous glass, pads, polyethylene glycol [PEG]/dextran, PEG/sodium chloride, NanoCeram/ViroCap, and ester membranes). The advantages and disadvantages of each method are considered, and the geographical areas where they are currently used are discussed. Several methods have demonstrated the ability to concentrate and recover PVs from environmental samples. The details of the particular sampling conditions and locations should be considered carefully in method selection.

The present study aimed to investigate the conversion of levulinic acid (LA) and cellulose (DP∼450) to γ-valerolactone (GVL) over Raney-Ni catalyst. In this process, hydrogenation was fulfilled usi...

The acid catalyzed condensations of ketones with glyoxylic acid at 80 °C, under neat conditions gives 4-oxo-2,5-heptdienedioic acids in 56–88% yield. The solid state photochemical dimerization of 4...

Renewable biomass based levulinic acid was converted to 5-methyl-2-pyrrolidone in 94% yield by a Raney-Ni catalyzed process using ammonium formate in aqueous medium and heating at 180 °C for 3 h. The Raney-Ni could be reused for four catalytic cycles with about 10% loss in catalytic activity. In a similar reaction levulinic acid could be converted 1-substituted-5-methyl-2-pyrrolidones in 90–95% yield by using a mixture of formic acid and the corresponding primary amine.

5-Hydroxymethylfurfural was converted to succinic anhydride in 90–92% yield by oxidation with 30% hydrogen peroxide using 10 mol% 1-(alkylsulfonic)-3-methylimidazolium chloride acidic ionic liquid catalysts at 60 °C for 14 h. The acidic ionic liquid catalyst could be reused for four catalytic cycles without appreciable loss in catalytic activity. On the other hand oxidation of furfural under similar ionic liquid catalyzed conditions produced a mixture of three products: 2(5H)-furanone, succinic anhydride and maleic acid in 68, 8 and 12% yields respectively.

Tissue inhibitor of metalloproteinase 2 (TIMP-2) is an endogenous 22 kDa proteinase inhibitor, demonstrating antitumorigenic, antimetastatic and antiangiogenic activities in vitro and in vivo. Recombinant TIMP-2 is currently undergoing preclinical testing in multiple, murine tumor models. Here we report the development of an inert, injectable peptide hydrogel matrix enabling encapsulation and sustained release of TIMP-2. We studied the TIMP-2 release profile from four β-hairpin peptide gels of varying net electrostatic charge. A negatively charged peptide gel (designated AcVES3) enabling encapsulation of 4 mg/mL of TIMP-2, without effects on rheological properties, facilitated the slow sustained release (0.9%/d) of TIMP-2 over 28 d. Released TIMP-2 is structurally intact and maintains the ability to inhibit MMP activity, as well as suppress lung cancer cell proliferation in vitro. These findings suggest that the AcVES3 hydrogel will be useful as an injectable vehicle for systemic delivery of TIMP-2 in vivo for ongoing preclinical development.

Kombucha SCOBY pellicle formed as a waste product in the kombucha tea fermentation industry can be used as a potential source for bacterial cellulose. We have compared four simple, scalable purification methods for the purification of this jelly like cellulosic matrix containing bacteria, yeast cells, proteins and polyphenols as impurities. The method using two successive 1.0 M NaOH washings at 90 °C, followed by the treatment with 1.5% (w/w) aq. NaOCl for 2 h, was the most effective method and gave the purified cellulose sample with the highest leucometer whiteness value of 81.4 ± 4.8. The purified cellulose samples were analyzed using FT-IR, TGA, SEM, EDX, X-ray and water absorption at room temperature.

Zinc as an essential element for humans was recognized in 1963. Nutritional zinc deficiency is now known to affect more than 2 billion human subjects globally. Zinc is an intracellular signaling molecule and it plays an important role in cell-mediated immune functions and oxidative stress. Zinc is also an antiinflammatory agent. These unique properties of zinc may have significant therapeutic benefits in several diseases in humans. In many diseases, concurrent zinc deficiency may complicate the clinical features, adversely affect immunological status, increase oxidative stress, and increase the generation of inflammatory cytokines. It is currently believed that oxidative stress and chronic inflammation may have important causative roles in many chronic diseases, including atherosclerosis, several malignancies, neurological disorders, and autoimmune diseases. It is therefore important that the status of zinc is assessed and zinc deficiency corrected in these chronic conditions. A controlled clinical trial of zinc supplementation in these disorders in order to document the preventive and therapeutic effects of zinc is recommended.

The kinetics and the mechanism of Dowex 50WX8 catalyzed conversion of d-fructose to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] via the intermediate 5-hydroxymethylfurfural was studied in DMSO. The first order rate constants for two step process was determined at 383 and 393 K by monitoring the concentrations of 5-hydroxymethylfurfural and 5, 5′-[oxybis(methylene)]bis[2-furaldehyde]. The activation energies for d-fructose to 5-hydroxymethylfurfural conversion and dimerization to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] were determined as 48.2 and 24.5 kJ mol−1. A detailed mechanism with four acid catalyzed dehydration steps is proposed for the one-pot conversion of d-fructose to 5, 5′-[oxybis(methylene)]bis[2-furaldehyde] based on 1H NMR studies in DMSO-d6 at 393 K.

Bronsted acid catalyzed condensations of meso-erythritol with aldehyde/ketones were studied using meso-erythritol:aldehyde/ketone 1:3 ratio in a Dean–Stark apparatus. The selectivity among bis-ketal and 1,3-dioxolane-ether formation can be achieved by choosing between homogeneous and heterogeneous catalysts. The catalysts could be reused without appreciable loss in activity.

D-Fructose was converted to the dialdehyde 5,5′-[oxybis(methylene)]bis[2-furaldehyde] by heating at 110 °C in DMSO with the Dowex 50 W X8 solid acid catalyst in 76% yield without the isolation of the intermediate 5-hydroxymethylfurfural. This dialdehyde was then converted to the dicarboxylic acid monomer, 5,5′-[oxybis(methylene)]bis[2-furancarboxylic acid], using oxygen (1 atm.) and 5% Pt/C catalyst in 1.5 M aqueous NaOH at room temperature in 98% yield. The new dicarboxylic acid monomer can be considered as a renewable resource based alternative to terephthalic acid as demonstrated by the preparation of polyesters with 1,2-ethanediol and 1,4-butanediol in 87–92% yield.

Carbamate cross-linked cellulose films can be prepared in a two step method using cellulose dissolved in 1-n-butyl-3-methylimidazolium chloride ionic liquid. The new technique involves casting the film from cellulose ionic liquid solution onto a glass surface and application of alkyl/aryl diisocyanate in dry dimethylsulfoxide solution onto the cellulose - ionic liquid coating on glass and allowing the cross-linking reaction to occur on the pre-formed cellulose coating. The carbamate cross-linked cellulose films formed were characterized by FT-IR, and TG-DTA. The water retention values of the films are shown to decrease with the increase in hydrophobicity of the alky/aryl group linker in the carbamate bridges.

Aims The aim of this study was to determine whether the allergy status and other characteristics of common cold patients modify the effects of zinc acetate lozenges. Methods We had available individual patient data for three randomized placebo-controlled trials in which zinc acetate lozenges were administered to common cold patients. We used both one stage and two stage meta-analysis to estimate the effects of zinc lozenges. Results The total number of common cold patients was 199, the majority being females. Eighty percent of them fell into the age range 20-50 years. One third of the patients had allergies. The one stage meta-analysis gave an overall estimate of 2.73 days (95% CI 1.8, 3.3 days) shorter colds by zinc acetate lozenge usage. The two stage meta-analysis gave an estimate of 2.94 days (95% CI 2.1, 3.8 days) reduction in common cold duration. These estimates are to be compared with the 7 day average duration of colds in the three trials. The effect of zinc lozenges was not modified by allergy status, smoking, baseline severity of the common cold, age, gender or ethnic group. Conclusion Since the effects of zinc acetate lozenges were consistent between the compared subgroups, the overall estimates for effect seemed applicable over a wide range of common cold patients. While the optimal composition of zinc lozenges and the best frequency of their administration should be further investigated, given the current evidence of efficacy, common cold patients may be encouraged to try zinc lozenges for treating their colds.

Condensation reactions of levulinic acid (LA) with 1,2-ethanediol (1,2-ED), 1,2-propanediol (1,2-PD), and 1,3-propanediol (1,3-PD) were studied using Amberlyst-15 as well as p-toluenesulfonic acid catalysts in benzene under Dean–Stark conditions. In Amberlyst-15 catalyzed reactions the products are ketals and ketal-esters, whereas p-toluenesulfonic acid catalyzed reactions produce esters and ketal-esters as products. In p-toluenesulfonic acid catalyzed reactions with 1,2-ED and 1,3-PD, LA monoester product is formed as the major product after 180 min in 75 and 97 % yields respectively. Unlike the previously reported acid catalyzed ketalization of ethyl levulinate with diols, combined ketalization–esterification of LA with diols is a complex process.

The effects of adding MnCl2 as a co-catalyst on cellobiose hydrolysis in 0.016 M aqueous H2SO4 and 0.032 M 1-(1-propylsulfonic)-3-methylimidazolium chloride acidic ionic liquid mediums were studied at 60–90 °C by measuring the glucose yields. The addition of MnCl2 produced enhancements in glucose yields in both aqueous acid mediums. The yield enhancements are highest at 60 °C and gradually decrease at higher temperatures, suggesting that a weak interaction of MnCl2 with cellobiose causes the co-catalytic effect. FT-IR studies in the solid-state suggest that MnCl2 interacts with hydroxyl groups of cellobiose without causing significant changes in the pyranose ring conformations.

Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

Electrochemical dimerization of vanillin in basic medium produced mixtures of meso/DL-hydrovanilloins, in contrary to earlier claims of the formation of meso-hydrovanilloin as the sole product. In the reinvestigation we have found that meso-percentage depends on the current density and the highest meso-percentage of 94% is achieved under 64 mA/cm2 current density, using Pb electrodes and 1.25 M aqueous NaOH as the electrolyte. Condensation of the renewable resources based monomer hydrovanilloin with formaldehyde in aqueous NaOH gives hydrovanilloin–formaldehyde polymer in 91% yield. The linear polymer is shown to contain hydrovanilloin units with methylene bridges connecting C-6 positions of the aromatic rings.

The interactions of cellulose model compound d-cellobiose with chloride salts of Zn(2+), Ca(2+), Li(+), Sn(2+), La(3+), Mg(2+), K(+) and NH4(+) were evaluated by measuring the (13)C NMR chemical shift changes (Δδ) of the disaccharide due to the addition of salts in D2O. The KCl and NH4Cl showed similar Δδ changes due to interactions only with the Cl(-) anion. Whereas other chloride salts showed interactions with both cation and anion. Among these salts the total interactions are in the order: Zn(2+)>Sn(2+)>Li(+)>Ca(2+)~La(3+)>Mg(2+). The FT-IR spectra of D-cellobiose-chloride salt 1:2 mixtures also indicate that KCl and NH4Cl interacts similarly with D-cellobiose in the solid state.

The current interest in biomass derived renewable furan derivatives furfural and 5-hydroxymethylfurfural commonly known as biofurans is due to their ready accessibility through dehydration of abundant cellulosic biomass derived monosaccharides. However, an upgrading to more stable compounds is an essential step for these materials in many sustainable fuel and chemical industry applications due to their instability and facile polymerization to humins. The aim of this article is to cover all aspects of catalytic upgrading reactions of biofurans, especially focusing on the developments in the last five years. The importance of this class of renewable feedstocks, preparation from monosaccharides as well as the diversity of possible transformations are discussed in the introduction sections of this review. The recent advances in catalytic reductions and oxidations of biofurans at CHO, OH functional groups, in ring system as well as rearrangements to form more stable value-added derivatives are reviewed. In addition, recently developed catalytic methods in carbon number upgrading of biofurans through condensation reactions and further conversions to renewable synthetic fuel range molecules are discussed in the article.

The acid catalyzed condensation of levulinic acid was studied using a series of solid acid catalysts: Amberlyst-15, SiO2-SO3H, Dowex50WX8, Carbon-SO3H, TiO2-SO3H, Al2O3-SO3H, H3PW12O40, and Nb2O5.H2O under neat conditions at 110–130 °C. The major dimerization product was identified as tetrahydro-2-methyl-5,γ-dioxo-2-furanpentanoic acid. In addition, four minor products were identified as diastereomeric pairs of 3-(2-methyl-5-oxo-tetrahydrofuran-2-yl)-4-oxopentanoic acid and 3-acetyl-2-methyl-tetrahydro-5-oxo-2-furanpropanoic acid by spectroscopic and computational methods. A mechanism is proposed to explain the formation of five dimerization products where the major product is formed via the aldol condensation of C5 enol form of levulinic acid and four minor products are arising from the aldol condensations C3 enol form of levulinic acid. The highest total yield 56% was obtained with the use SiO2-SO3H as the solid acid catalyst and the reminder of the mass balance was unreacted levulinic acid. The SiO2-SO3H catalyst could be recycled four times with some loss in catalytic activity.

Furanic bio-oils were produced from liquefaction of corn cobs and switchgrass using 1-(3-propylsulfonic)-3-methylimidazolium chloride catalyst in acetone at 120 °C, 5 h. The biomass conversions to bio-oils for corn cobs and switchgrass were 43.8 ± 1.9 and 40.2 ± 1.4% (w/w) respectively. The bio-oils were then catalytically hydrogenated in water: methanol 3:1 (v/v) at room-temperature and atmospheric pressure using 5% Pd-C catalyst to give hydrogenated bio-oils and analyzed using GC–MS to identify the products. GC–MS analysis revealed that majority of the products in hydrogenated bio-oils is C4-C17 alcohols, ethers and furans. A total of 64 products were observed in GC–MS and 61 were identified with the use of mass spectroscopy. These products are arising from the partial reduction as well as deoxygenation of biomass derived furan aldehyde - acetone cross aldol products and acetone self condensation products. In addition, NMR analysis was used to quantify the effect of catalytic hydrogenation. 1H NMR spectra peak integration for the alkene-furan region (6.0–8.0 ppm) showed reductions of 19.0 to 1.8% and 19.1 to 2.6% due to the catalytic hydrogenation of bio-oils from corn cobs and switchgrass, confirming the effect of Pd-C catalyzed, 1 Atm., room temperature hydrogenation.

The hexose dehydration product and important renewable feedstock 5-hydroxymethylfurfural can be biocatalytically reduced to 2,5-furandimethanol in 96% yield using coconut (Cocos nucifera L.) water as the biocatalyst at room temperature. The dimer of 5-hydroxymethylfurfural 5,5'-[oxybis(methylene)]bis[2-furaldehyde] can also be reduced to the corresponding diol 5,5'-[oxybis(methylene)]bis-[2-furanmethanol] using coconut (Cocos nucifera L.) water in 95% yield under similar conditions. This biocatalytic system could be reused in four cycles without an appreciable loss in activity.

Effective host responses to injury and infection require both rapid recruitment of neutrophils into tissues and timely inflammation resolution. Research currently focuses on initiation and resolution as distinct phases of inflammation and neutrophil survival as a key determinant of the inflammatory response. Less focus has been placed on mechanisms retaining viable neutrophils at inflamed sites and thus contributing to ongoing inflammation. This may be of therapeutic importance given the numerical dominance of viable over apoptotic neutrophils in inflamed tissue, even during inflammation resolution. Semaphorins are proteins that regulate motility in a variety of cell types and systems. We observed that neutrophils regulate Sema3F transcript abundance, which is expressed in the airway myeloid cell population of COPD patients. We then questioned whether Sema3F could regulate neutrophil migration and define the magnitude of the inflammatory response. Not only do inflammatory neutrophils express the class 3 Semaphorin, Sema3F and its obligatory co-receptor Neuropilin 2 (NRP2) but expression of both is further induced by bacterial Lipopolysaccharide (LPS) and other inflammatory stimuli. In a murine model of LPS-induced acute lung injury, we describe a phenotype where neutrophil specific knockdown of Sema3F both increases neutrophil recruitment to the airways 6 hours following LPS challenge (***p=0.0079, n=9) and enhances the rate of inflammation resolution (wild-type airway neutrophil count T50=42 hours, Sema3F knockout T50=32.9 hours). Conversely, intra-tracheal instillation of Sema3F in wild-type mice retains neutrophils at the injury site following maximal recruitment (p=0.046, n=8). In vitro experiments using human neutrophils demonstrate Sema3F reduces neutrophil chemotaxis producing ‘rounder cells’, phagocytosis is unaffected but interestingly respiratory burst is enhanced (*p=0.0117, n=3). Using confocal microscopy and image analysis software we identified the location of the neutrophils in the murine lung interstitium following LPS induced lung injury. We show that intra-tracheal Sema3F holds the recruited neutrophils in the alveolar space (*p

The hydrolysis of cellulose model compound d -cellobiose was studied with a series of eight common polycarboxylic acids and two monocarboxylic acids in aqueous medium using 0.500 mmol -COOH/L at 170 °C. The maleic acid showed the highest catalytic activity with turnover frequency (TOF) of 29.5 h−1. The interaction of carboxylic acids with d -cellobiose in DMSO‑d6 was studied by determination of the pseudo first-order rate constant kH of anomeric -OH exchange rate in cellobiose using 1H NMR spectroscopy. The maleic, oxalic and citric acids showed infinitely large kH values indicating very strong interactions with d -cellobiose. The next highest interactions were found with phthalic acid (kH = 248.8 Hz). The FT-IR studies showed significant carboxylic acid C=O stretching frequency shifts (ΔνC=O) of 12, 13 and 10 cm−1 for maleic, oxalic and acetic acids respectively in mixtures with d -cellobiose.

In this study we have assessed zinc status and zinc-dependent cell-mediated immune functions (interleukin-2 production by mononuclear cells, natural killer cell lytic activity, and interleukin-1β production by mononuclear cells) in adult patients with squamous cell carcinoma of the upper aerodigestive tract at diagnosis and before any therapy was instituted. Inasmuch as significant interactions between zinc, copper, and iron exist, we also assayed the plasma copper level, serum iron level, and total iron-binding capacity in our patients. We recruited 30 cancer subjects and 21 control subjects. On the basis of cellular zinc criteria, we diagnosed a mild deficiency of zinc in 53% of cancer subjects. The plasma zinc level was not decreased in our subjects. A univariate analysis was applied by use of one-way analysis of variance comparing study variables among the three study groups (controls and zinc-deficient and zinc-sufficient cancer patients) and Tukey's multiple comparison test, and we showed that interleukin-2 production and natural killer lytic activity were decreased in zinc-deficient cancer patients. Interleukin-1β production (ELISA assay) was increased in both zinc-deficient and zinc-sufficient groups. Plasma copper level was not different, but the iron utilization was decreased in both groups of cancer subjects. We conclude that zinc deficiency and zinc-dependent immunologic dysfunctions are present in more than half of the patients with head and neck cancer in the Detroit area.

The metal salt – Bronsted acidic ionic liquid system composed of ZnCl2·1.74H2O-1-(1-propylsulfonic)-3-methylimidazolium chloride can directly hydrolyze untreated cellulose in 78% total reducing sugar and 19% glucose yield at 37 °C, 1 atm in 4.0 days. The new chemical catalyst is used at a temperature lower than typical cellulase enzyme operating conditions.