Mortaza Gholizadeh

Acid-catalyzed conversion of mono- and poly-sugars into platform chemicals: Effects of molecular structure of sugar substrate

Hydrolysis/pyrolysis of lignocellulosic biomass always produces a mixture of sugars with distinct structures as intermediates or products. This study tried to elucidate the effects of molecular structure of sugars on their acid-catalyzed conversions in ethanol/water. Location of carbonyl group in sugars (fructose versus glucose) and steric configuration of hydroxyl groups (glucose versus galactose) significantly affected yields of levulinic acid/ester (fructose>glucose>galactose). The dehydration of fructose to 5-(hydroxymethyl)furfural produces much less soluble polymer than that from glucose and galactose, which results in high yields of levulinic acid/ester from fructose. Anhydrate sugar such as levoglucosan tends to undergo the undesirable decomposition to form less levulinic acid/ester. Catalytic behaviors of the poly-sugars (sucrose, maltose, raffinose, β-cyclodextrins) were determined much by their basic units. However, their big molecular sizes create the steric hindrance that significantly affects their followed conversion over solid acid catalyst.

The nitrogen cycle in air, soil and water

A new reaction-based probe for the fluorescence signaling of Hg2+ ions using dithiane derivative of ESIPT probe has been investigated. Probe showed prominent off-on type fluorescence signaling behaviour towards Hg2+ ions in aqueous DMSO solution. The interfering response of Cu2+ ions was efficiently removed by using a citrate buffer as a masking agent. By using citrate buffer, the selective signaling behaviour is not affected by the presence of other metal ions that are usually present in environmental samples. Hg2+ ions signaling by a large fluorescence enhancement (66-fold) was possible with a detection limit of 1.8 ×10-7 M.As a test of a practical use for the designed probe, we created a test strip that could be used to detect Hg2+ ions in aqueous solution.D lysosomal Zn(II) is an important issue because it acts as downstream marker for the LMP process. Development of fluorescent probe which can detect lysosomal Zn(II) ions is necessary to study the oxidative stress levels in biological systems. Herein, we have developed innovative two-photon probe using naphthalimide dye composed of N,N-di-(2-picolyl) ethylenediamine (DPEN) ligand and a morpholine unit. The probe can detect Zn(II) ions in lysosomes with high sensitivity and selectivity over the most competing Cd(II) ions. The probe can also enabled fluorescence imaging of mouse brain tissues under two-photon excitation at 900 nm. The probe can be an effective tool for studying biological processes related to lysosomal Zn(II) ions by two-photon microscopy.Background: Calcineurin (CN) is a Ca 2+ /calmodulin- dependent phosphatase and has been implicated in both transcription-dependent and transcription-independent apoptosis. Objectives: We aim to interpret the correlation between CN and apoptosis in relation to pathogenesis of breast cancer. Materials and Methods: Both CN level and activity, as well as caspase-3 activity, were evaluated in tissue homogenate of 50 breast cancer patients, 20 patients with fibroadenoma and 15 healthy women. Results: CN activity was significantly decreased in malignant breast tissues compared with fibroadenoma and normal breast tissue (P 0.05). While caspase-3 showed a significant higher activity in a malignant group compared with other groups (P < 0.05). In addition, there was a significant negative correlation between CN activity with grade, stage (P < 0.001) and a significant positive correlation with its level (P = 0.039). Conclusion: CN activity, but not its level might have a role in breast neoplasia; restoration of its normal activity may act as an adjuvant factor to control breast cancer pathogenesis.T smart and simple spectrophotometric methods are developed and validated for simultaneous determination of Itopride hydrochloride (IT) and Rabeprazole sodium (RB) in their binary mixture namely; Constant Center method (CC) and Ratio difference method (RD). The calibration curves are linear over the concentration range of 10-110 μg /μL for Itopride hydrochloride and 4-44 μg /μL for Rabeprazole sodium, with mean recoveries 99.69 ± 0.391, 99.86 ± 0.440 for Itopride hydrochloride using CC and RD; respectively and 100.39 ± 0.537, 100.25 ± 0.458 for Rabeprazole sodium using CC and RD methods; respectively. The proposed methods are applied to pharmaceutical formulation without preliminary separation steps. To assess the speceficity of the methods, analysis of synthetic mixtures containing different ratios of the two studied drugs and their capsules dosage form is done. The statistical comparison shows that there is no significant difference between the results obtained by the proposed methods and the reported HPLC method with regard to both accuracy and precision.The applied methods are validated according to ICH guidelines and can be used for quality control laboratories for the studied mixture. The proposed methods have lower cost and more environmental friendly than the HPLC ones. The methods are also appropriate to be used in laboratories which have deficiency in liquid chromatographic instruments.M frameworks (MOFs) have potential applications in the fields of sorption and separation, catalysis and luminescence. Here, a 3D compound {[Zn2(BPF)(NH2-BDC)2]}n (1) was constructed with 2,7′-bis(4-pyridyl)fluorine (BPF) and 2-aminoterephthalic acid (NH2-BDC ) as bridging ligand. The single crystal X-ray study showed that compound 1 displays pillar-layered structure. The solid-state emission spectra of the compound have been studied at room temperature. Compound 1 shows strong emission at 495 nm, which is stronger than that observed in the free BPF (424 nm). The enhancement of luminescence may be attributed to the chelation of ligand with metal center, which effectively increases the rigidity of the ligand and reduces the loss of energy by radiation decay. The band gap (2.75 eV) was measured by a solid state visible light diffuse reflection measurement method at room temperature. We select methylene blue (MB) as a model of dye contaminant to evaluate the photocatalytic effectiveness. Approximately 50% of MB was degraded in four hours under neon light at 500 W.T determination of minerals and trace elements in foodstuffs is an important part of nutritional and toxicological analyses. Although copper, chromium, iron and zinc play an important role in human metabolism and so, they are essential micronutrients for human health. Their higher intake as well as the prolonged intake of even low concentration (Ni) can cause serious toxic effects. The interest in these elements is increasing together with reports of relationships between trace element status and oxidative diseases. Environmental pollution is the main cause of heavy metal contamination in the food chain. Of all foods, legumes most adequately meet the recommended dietary guidelines for healthful eating because they are high in carbohydrate and dietary fiber, mostly low in fat, supply adequate protein while being a good source of vitamins and minerals. In this study, nickel and chromium concentrations were determined in legumes taken from Turkish markets. Further, sulfur concentrations of the samples were also determined and the relationship between metals and sulfur were examined. The element concentrations were measured by using ICP-MS after digestion by microwave digestion system. It was found that the highest Ni concentration is 2.5 mg/kg for beans. To check the reliability, the SRM was examined for the studied elements.T oral delivery of anticancer drugs represents a significant challenge for global scientist. N-trimethyl chitosan (TMC) is a polymer with the potential to facilitate effective oral drug delivery. Recently, the peptide CSKSSDYQC (CSK) has been conjugated to TMC as a means of active goblet cell targeting for gastrointestinal uptake. The aim of the study is to develop and optimize a TMC-CSK modified nanoparticules for oral delivery of gemcitabine. TMC was synthesised from deacetylated chitosan using a novel two-step synthesis, then conjugated with CSK to actively target goblet cells. Gemcitabine-loaded TMCCSK nanoparticles were prepared via ionic gelation. Characterisation studies including particle size, zeta potential, entrapment efficiency and in vitro drug release were then carried out. Cytotoxicity of drug solution and drug loaded formulation was tested on 4T1 breast cancer cell. Lastly, in-vivo pharmacokinetic and pharmacodynamics studies were conducted. The results showed the optimal delivery system showed particle size of 173.6±7.7 nm and zeta potential of 18.5±0.2 mV. Entrapment efficiency of 66.44±0.02%, and a sustained drug release profile was obtained. LD50 of 0.23 μg/mL was determined in cytotoxicity studies. Gemcitabine loaded TMC-CSK nanoparticles significantly improved the oral bioavailability, raised the plasma half-life, and AUC0-∞ of 4.5 fold higher than for gemcitabine solution in pharmacokinetic studies. Obvious tumour size reduction of 2.6 fold was observed for TMC-CSK nanoparticles compared to drug solution in pharmacodynamics studies. In conclusion, gemcitabine can be delivered using this TMC-CSK modified nanoparticulate delivery systems via oral route to elevate its oral bioavailability and therapeutic anticancer effect.O of the methods of obtaining functionalized heterocycles is the 1,3-dipolar cycloaddition reaction involving nitroalkenes as dipolarophiles containing a trihalogenmethyl group at β-position in their structure. 1,3 dipolar cycloaddition of phenylazide to 1 nitroand 1 bromo 1 nitro 3,3,3 trifluoro(chlorine)propenes was carried out through the intermediate formation of regioisomeric triazolines, which under the reaction conditions underwent intramolecular transformation (denitration, dehydrogenation, dehydrohalogenation) culminating in the formation of the corresponding triazoles with or without nitro-group. The structure of obtained compounds is proved by modern physical-chemical research methods and the formation of these compounds does not contradict with reference data on such adducts obtaining in reaction of 1,3-dipolar cycloaddition with the same structure type nitroalkenes which contain CO2R and P(O)(OR)2 groups instead of the С(Hlg)3 substitute in their structure.T contribution will explore cutting edge molecular (Raman, IR, fluorescence, SNOM, AFM, TERS, femtosecond spectroscopy) mapping and time resolved dynamics of cellular structures of cancers, localization of drugs and nanoparticles in cells and tissues. The multidisciplinary nature of the studies span the a diverse range of biological, chemical, and physical sciences related to cancer biology. This contribution will provide insight regarding the new molecular mapping and their ability to monitor biochemistry of biomolecules in the cells and tissues, distribution of drugs, and nanomaterials as they interact with cells and tissues. The main focus will be on the presentation of integrated picture of cancer by near field microscopy SNOM, AFM and hyperspectral Raman imaging to look inside human breast ducts. We will demonstrate how this approach gives important answer about location and distribution of biochemical components in human cells and tissue during cancer development. The lecture shows new look inside human breast duct using Raman imaging, an emerging technology of molecular imaging, that may bring revolution in understanding of cancer biology. Our contribution is a first report in the literature demonstrating such a detailed analysis of normal and cancerous ducts in human breast tissue. The main advantage of Raman imaging is that it gives spatial information about various chemical constituents in defined cellular organelles in contrast to conventional methods (LC/MS, NMR, HPLC) that rely on bulk or fractionated analyses of extracted components.