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Non-wood raw materials are an essential fiber source in regions where forest resources are limited. Therefore, chemi-mechanical high-yield bagasse pulp was prepared and then bleached with a dithionite bleaching agent. One- and two-stage bleaching of the pulp was carried out by using sodium dithionite (Y) as a sole bleaching agent, or after bleaching with hydrogen peroxide to achieve high brightness for the prepared pulp. Different parameters, such as consistency, concentration, temperature, time and pH were investigated. The effect of various additives, such as diethylenetriaminepentaacetic acid (DTPA) as chelating agent or Zn compounds and hexamethylenetetramine to stabilize the bleaching solution, was studied. The effect of dissolved oxygen in liquor was also considered.

Microcrystalline cellulose (MCC) is a bio-based material obtained from purified and partially depolymerized cellulose. The need for cheaper sources of MCC has led to the exploration of other lignocellulosic material based on agricultural residues. Hence, in this study, olive stones were chosen as olive industry produces 37,500 tons of olive-stone waste every year. Microcrystalline cellulose was prepared by acid hydrolysis using hydrochloric or sulfuric acids then bleached. Characterization of the prepared MCC was carried out using attenuated reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and thermal gravimetric analysis (TGA). The crystal structure was studied using XRD. The surfaces of prepared samples were investigated by field emission scanning electron microscope (SEM). In addition, surface area and pore size, as well as particle size distribution of the prepared samples, were measured using nitrogen absorption isotherm and dynamic laser light scattering, respectively. The particle size of samples prepared with sulfuric acid was smaller and therefore the surface area was higher than in case of samples prepared using hydrochloric acid. However, the hydrochloric acid prepared MCC had higher thermal stability than the other sample prepared using sulfuric acid. The properties of prepared MCCs were compared to the commercially available MCC (Avicell PH 101); the results showed good agreement in most properties between olive stone MCC and the commercial one.

This research aimed to prepare smart cotton fabrics with multi functions for antibacterial activity, UV protection and electrical conductivity via in situ coating with conductive polymer and conductive hydrogel. Therefore, 3-(furan-2-carboamido) propionic acid was synthesized followed by polymerization using ceric ammonium nitrate. In addition, cotton fabrics coated with 3-(furan-2-carboamido) propionic acid via in situ polymerization and by the hydrogel that based on poly (3-(furan-2-carboamido) propionic acid) and gelatin which have been performed via in situ gelation process. The chemical structure and morphology of the 3-(furan-2-carboamido) propionic acid (monomer) and the synthesized polymer (PFu) were investigated by H1NMR, IR, SEM, TGA and DSC. Where, the treated fabrics (PFu-T and PFu-G-T) are characterized by SEM, FTIR and contact angle. Furthermore, the AC electrical conductivity and dielectric properties of PFu, PFu-T, PFu-G-T and blank were investigated over the frequency range of 20 Hz–10 MHz at room temperature using impedance spectroscopy where the electric conductivity values are 1.74 × 10-5, 7.5 × 10-8, 4 × 10-7, 8.24 × 10-11 (S·cm)-1, respectively. In addition, the anti-bacterial activity of PFu-T, PFu-G-T and blank was assessed versus gram-positive and gram-negative bacteria where, PFu-G-T shows activity against Escherichia coli and Staphylococcus aureus. Moreover, PFu-T, PFu-G-T showed high UV protection especially for PFu-G-T.

New sugar hydrazones incorporating furan and/or 1,3,4-thiadiazole ring systems were synthesized by reaction of the corresponding hydrazide with different aldose sugars. Heterocyclization of the formed hydrazones afforded the derived acyclic nucleoside analogues possessing the 1,3,4-oxadiazoline as modified nucleobase via acetylation followed by the heterocyclization process. The anticancer activity of the synthesized compounds was studied against human liver carcinoma cell (HepG-2) and at human normal retina pigmented epithelium cells (RPE-1). High activities were revealed by compounds 3, 12 and 14 with IC50 values near to that of the reference drug doxorubicin.

Background & Objective:The target tetrazole glycosides were synthesized by construction of ring system by cycloaddition reaction of benzothiazole-linked nitrile derivative and sodium azide followed by N-glycosylation process and deprotection.Methods:The triazole glycosides were prepared by applying click approach involving dipolar cycloaddition of benzothiazole possessing alkyne functionality and different glycosyl azides. The products incorporating acyclic analogs of sugar moieties were synthesized through alkylation using acyclic oxygenated halides.Results:The anticancer activity was studied against human breast adenocarcinoma cells (MCF-7) and human normal Retina pigmented epithelium cells (RPE-1). High activities were revealed by three compounds with IC50 values 11.9-16.5 µM compared to doxorubicin (18.6 µM) in addition to other four derivatives with good inhibition activities.Conclusion:Enzyme docking investigation was performed into cyclin-dependent kinase 2 (CDK2); a potential target for cancer medication. Compounds which have possessed highest activities revealed good fitting inside the binding site of the protein molecular surface and showed minimum binding energy.

Senecio vulgaris L. is a well known toxic plant, phytochemical investigation of the whole plant afforded the isolation of a new coumarin; 3,7-dihydroxy-5,6 dimethoxycoumarin-7-O-β-D-glucoside (1), in addition to the isolation of isorhamnetin-3-O-β-D-glucoside (2) and two known alkaloids of common occurrence in genus Senecio; senecionine (3) and seneciphylline (4). The isolated compounds were identified by physical and chemical analyses and by intensive investigation of their spectral data. EtOH extract, light petrol and CHCl3 fractions of S.vulgaris were found to have cytotoxic activity on colorectal cell line HCT-116 cell line, with IC50 values of 19.9, 27.3 and 17.8 μg mL-1, respectively. That indicates the most active cytotoxic fraction is the alkaloid-bearing chloroform fraction. These findings promote the future perspective of S. vulgaris as an anticancer agent. The antioxidant activity of EtOH extract, light petrol fraction and CHCl3 fraction was evaluated by DPPH assay, %inhibition was 23.31, 4.677 and 17.598, respectively. Also the ratio between senecionine and seneciophylline in their mixture was determined using 1H-NMR spectrum.

Some novel 1-(inden-3-ylidene)-2-(thiazol-2-ylidene)hydrazine derivatives 3–9 were synthesized by the Hantzsch reaction of thiosemicarbazone derivatives 2a–2c with halo ketones and halo esters. Thiosemicarbazone derivatives reacted with hydrozonyl chlorides to give diazenyl-4-methylthiazole derivatives 11a–11d. Structures of the products were elucidated from IR, 1H, and 13C NMR, and Mass spectra elucidate. The synthesized compounds were screened for their cytotoxicity against three human tumor cell lines. Twenty compounds showed high (≥60 %) antiproliferative activity over breast cancer (MCF-7). Compounds 2b, 3c, 4a, 4b, 6b, 6c, 7b, 8a, and 11b possessed higher cytotoxic activity over breast tumor cell line than Doxorubicin.

A series of hydroxypropyl cellulose (HPC)/oxidized cellulose nanocrystals (OXCNC) nanocomposites films was prepared via casting and evaporation. OXCNC was used in ratios from 2.5 to 20% in HPC matrix. The prepared nanocomposites films were evaluated using scanning electron microscopy (SEM), X-ray diffraction (XRD), dynamic mechanical thermal analysis (DMTA), tensile strength properties (TS) and water vapor permeability (WVP). Significant increase in the crystallinity and tensile strength accompanied by an increase in WVP of HPC films occurred as a result of adding OXCNC. HPC/10% OXCNC film was found to possess the maximum tensile strength properties and that composition was chosen for coating bagasse paper sheets. Coating of paper sheets increased TS, WVP and decreased porosity of the paper sheets. The slight increase in WVP of the films and the coated paper sheets was attributed to the hydrophilic nature of OXCNC.

A practical fluorescent test dipstick for an efficient recognition of ammonia and amines vapors was developed. The prepared testing strip was based on a composite of molecularly imprinted chitosan nanoparticles, supported on cellulose paper assay, with artificial fluorescent receptor sites for ammonia/amines recognition in aqueous and gaseous phases. A modified chitosan nanoparticles containing fluorescein molecules, were successfully prepared and employed on cellulose paper strip creating fluorescent cellulose (FL-Cell) to act as “turn-on” fluorescent sensor for sensing and determining ammonia and organic amine vapor. We employed chitosan nanoparticles that had fluorescein incorporated as the fluorescent probe molecule, with a readout limit achieved for aqueous ammonia as low as 280 ppm at room temperature and atmospheric pressure. The sensor responded linearly relying on the aqueous ammonia concentration in the range of 0.13–280 ppm. The chromogenic fluorescent cellulose platform response depended on the acid-base characteristic effects of the fluorescein probe. The protonated form of fluorescein molecules immobilized within the chitosan nanoparticles were in a nanoenvironment demonstrating only weak fluorescence. When binding to ammonia/amine vapor, the fluorescein active sites were deprotonated and exhibited higher “turned-on” fluorescence as a result of exposure to those alkaline species. The simple fabrication and abovementioned characteristics of such fluorescent chitosan nanoparticles are such that they should be applicable for monitoring of ammonia/amines in either aqueous or vapor states. We studied the distribution of the fluorescent chitosan onto paper sheets fabricated from bleached bagasse pulp and coated with two different thicknesses of a fluorescent nanochitosan and blank nanochitosan solutions. A thin fluorescent nanochitosan layer was created on the surface of cellulose strips using an applicator. Its distribution was assessed by scanning electron microscopic (SEM) and transmission electron microscopic (TEM) analysis as well as Fourier-transform infrared spectroscopic (FT-IR) measurements. The mechanical properties were also tested. The exploitation of this “turn-on” fluorescence sensor invented platform should be amenable to different situations where determination of ammonia/amine vapor or aqueous solution is required.

A new series of 4-phenylcoumarin derivatives was synthesized starting from (2-oxo-4-phenyl-2H-chromen-7-yloxy) acetic acid hydrazide 3. Evaluation of the target compounds for their antiviral activity against hepatitis A virus revealed that the ethylthiosemicarbazide derivative 7b was the most potent virucidal agent (IC50 = 3.1 μg/ml, TI = 83). The Schiff's bases 14c and 14b demonstrated the highest virustatic effects against viral adsorption and replication, respectively (14c; IC50 = 8.5 μg/ml, TI = 88 and 14b; IC50 = 10.7 μg/ml, TI = 91). Furthermore, compounds 7b, 14b and 14c were tested against HAV 3C protease and showed significant inhibition effects (Ki = 1.903, 0.104 and 0.217 μM, respectively). The remarkable inhibitory effect expressed by the three target compounds against HAV 3C protease prompted us to expand our research on HRV 3C protease, a structurally related enzyme of the same family, and interestingly, the three target compounds displayed significant inhibitory effect against HRV 3C protease (IC50 = 16.10, 4.13 and 6.30 μM, respectively). Moreover, the active compounds 7b, 14b and 14c were docked within the pocket site of HAV 3C protease (PDB code: 2HAL ) illustrating a strong H-profile with the key amino acids Gly170 and Cys172 similar to the co-crystallized ligand. Furthermore, 3D-pharmacophore and quantitative structure activity relationship (QSAR) models were generated to explore the structural requirements for the observed antiviral activity.

In this study, an ultra-performance liquid chromatography (UPLC)/photodiode array method was developed for the simultaneous determination of trigonellan glucoside (1), isotrigonellan (2), and methoxy-isotrigonellan (3) in Trigonella stellata extract using an external standard method. The extract was prepared using a standardized method by maceration of the dried plant material in ethanol. The 3 isoflavans (1-3) were separated on an Acquity UPLC C18 column using gradient elution with a mobile phase consisting of 0.1% (v/v) formic acid aqueous solution and 0.1% (v/v) formic acid in acetonitrile, and ultraviolet detection. The method provides a linear correlation for all analytes over the investigated ranges with all correlation coefficients greater than 0.998. The validated lower limits of quantitation were 53, 127, and 5 μg/mL for isoflavans 1, 2, and 3, respectively. Intraday and interday precisions (percent relative SD [RSD%]) were less than 8.3% and accuracy (RE%) ranged from 90% to 100%. The method’s capability to remain unaffected by small, but deliberate variations in method parameters (method’s reliability during normal usage) described by the robustness showed RSD% less than 4.6% measured by varying 3 different parameters. The validated method was successfully applied to simultaneously determine the concentration of the 3 new isoflavans having anti-inflammatory and antidiabetic activities. The results revealed that the validated method can be used for quality control of herbal preparations containing these or similar isoflavans that are marketed for the prevention of inflammation and as antidiabetics.

Background & Objective:Quinazolines and their fused systems are noteworthy in pharmaceutical chemistry due to their wide range of biological activities.Methods:A direct and efficient approach for the synthesis of new series of fused quinazolines with triazole, thiazole, benzimidazole and tetrazole has been preceded via the reaction of quinazoline thione derivative with halogenated compounds or cyclocondensation of arylidene of quinazoline derivative with heterocyclic amines. Also, dibenzo[b,e][1,4]thiazepine derivatives was synthesized through the reaction of 2,6-bis-(2-chloro-benzylidene)-cyclohexanone with o-aminothiophenol.Results:The structures of all new synthesized heterocyclic compounds were confirmed and discussed on the bases of spectral data. The utility of the preparation and design of the above mentioned compounds has been shown to be clear in the results of their antimicrobial activity which revealed that some derivatives have potent activity exceeding or similar to the activity of the reference drugs.Conclusion:The insertion of triazole or thiazole moieties to be fused with quinazoline ring helps to enhance its antimicrobial activity.

1,3-Thiazol derivatives have been synthesized via reaction of 1-(1-(5,6-dimethoxy-2-oxobenzo[d]thiazol-3(2H)-yl)propan-2-ylidene)-4-substituted thiosemicarbazide with different halides, namely, ethyl bromoacetate, ethyl-2-bromopropionate, phenacyl bromide, p-bromophenacyl bromide and/or substituted hydrazonoyl halides. The new compounds were evaluated as antimicrobial agents.

Benzothiazoles have been proven to be potent antimicrobial agents. In this study, 3-(5,6-dimethoxy-2-oxo-1,3-benzothiazol-3(2 H )-yl)propanohydrazide has been utilized as a scaffold for synthesis of pyrrole, indolylidene, pyrazoles, mercaptotriazole, oxadiazole, triazole and oxothiazolidine derivatives. Structures of the synthesized compounds were elucidated on the basis of elemental analyses and spectral data. All the synthesized compounds were screened for their antimicrobial activity.

A new inorganic/sugar beet pulp composite that can be used as anion exchanger material was prepared from sugar beet pulp (SBP) after loading with zirconium (IV) ions. The prepared anion exchanger material was examined for its ability to remove sulfate and nitrate anions from water. The effect of contact time, anions concentration, temperature, and pH on the adsorption capacity of Zr(IV)-loaded SBP was studied. The maximum adsorption capacity of Zr(IV)-loaded SBP was about 114 mg/g and 63 mg/g for sulfate and nitrate, respectively. In addition, the effect of the regeneration of the Zr-loaded SBP after anion removal has been studied. The results of anions adsorption test and EDX-SEM showed that zirconium ions are strongly bound to the carboxylate groups of SBP constituents, especially pectins, and are not leached as a result of regeneration. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The aerial parts of Lactuca sativa afforded lactucin, 1 11β,13-dihydrolactucin, lactupicrin, a new melampolide and 3β,14-dihydroxy-11β,13-dihydrocostunolide.

The aerial parts of Hedypnois cretica afforded four sesquiterpene lactones all closely related to hypnocretenolide. Two lactones were glucopyranosi