International Journal of Carbohydrate Chemistry The latest articles from Hindawi © 2017 , Hindawi Limited . All rights reserved. Synthesis and Antimicrobial Activity of N-(6-Carboxyl Cyclohex-3-ene Carbonyl) Chitosan with Different Degrees of Substitution Sun, 23 Oct 2016 08:33:38 +0000 Five products of -(6-carboxyl cyclohex-3-ene carbonyl) chitosan as antimicrobial agents were prepared by reaction of chitosan with tetrahydrophthalic anhydride (THPA) at different degrees of substitution (DS). The antimicrobial activity was evaluated against four plant bacteria and eight fungi. The results proved that the inhibitory property and water solubility of the synthesized chitosan derivatives, with increase of the DS, exhibited a remarkable improvement over chitosan. The product with a DS of 0.40 was the most active one with MIC of 510, 735, 240, and 385 mg/L against Erwinia carotovora, Ralstonia solanacearum, Rhodococcus fascians, and Rhizobium radiobacter, respectively, and also in mycelial growth inhibition against Alternaria alternata (EC50 = 683 mg/L), Botrytis cinerea (EC50 = 774 mg/L), Botryodiplodia theobromae (EC50 = 501 mg/L), Fusarium oxysporum (EC50 = 500 mg/L), F. solani (EC50 = 260 mg/L), Penicillium digitatum (EC50 = 417 mg/L), Phytophthora infestans (EC50 = 298 mg/L), and Sclerotinia sclerotiorum (EC50 = 763 mg/L). These compounds based on a biodegradable and biocompatible chitosan could be used as potentially antimicrobial agents in crop protection instead of hazardous synthetic pesticides. Mohamed E. I. Badawy and Entsar I. Rabea Copyright © 2016 Mohamed E. I. Badawy and Entsar I. Rabea. All rights reserved. Biosynthesis and Biological Activity of Carbasugars Sun, 31 Jul 2016 13:43:51 +0000 The first synthesis of carbasugars, compounds in which the ring oxygen of a monosaccharide had been replaced by a methylene moiety, was described in 1966 by Professor G. E. McCasland’s group. Seven years later, the first true natural carbasugar (5a-carba-R-D-galactopyranose) was isolated from a fermentation broth of Streptomyces sp. MA-4145. In the following decades, the chemistry and biology of carbasugars have been extensively studied. Most of these compounds show interesting biological properties, especially enzymatic inhibitory activities, and, in consequence, an important number of analogues have also been prepared in the search for improved biological activities. The aim of this review is to give coverage on the progress made in two important aspects of these compounds: the elucidation of their biosynthesis and the consideration of their biological properties, including the extensively studied carbapyranoses as well as the much less studied carbafuranoses. Silvia Roscales and Joaquín Plumet Copyright © 2016 Silvia Roscales and Joaquín Plumet. All rights reserved. Dissolution of (1-3),(1-4)-β-Glucans in Pressurized Hot Water: Quantitative Assessment of the Degradation and the Effective Extraction Tue, 17 May 2016 10:01:57 +0000 The purpose of this work was to study the behavior of (1-3)(1-4)-β-D-glucan in pressurized hot water. For this purpose, solid β-glucan (450 kDa) was put in water and heated at different temperatures (120, 150, and 170°C) for different times (5 to 360 minutes). At 120°C it was found that the highest soluble β-glucan concentration was measured after 60 minutes; at 150 and 170°C optimal times were 45 and 20 minutes, respectively. The maximum amount of β-glucan dissolved in each of the optimal conditions was 1.5, 2.2, and 2.0 g/L, respectively. Under those conditions an important reduction was observed in the molecular weight: at 120°C and 60 min it was 63 kDa; at 150°C and 45 min it was reduced down to 8 kDa; and at 170°C and 20 min it was only 7 kDa. Besides this reduction in the MW some hydrolysis products, such as glucose and HMF, were observed. These results revealed the convenience of using PHW to dissolve β-glucans since the operation times, compared to the conventional process (55°C, 3 h), were reduced despite the fact that the MW was significantly reduced once the β-glucan was dissolved; therefore, PHW can be used to extract β-glucans from barley under controlled conditions in order to prevent severe degradation. Óscar Benito-Román, Alexandra Martín-Cortés, María José Cocero, and Esther Alonso Copyright © 2016 Óscar Benito-Román et al. All rights reserved. Total Chlorine-Free Bleaching of Populus deltoides Kraft Pulp by Oxone Wed, 12 Aug 2015 09:41:17 +0000 Since the bleaching process is one of the most important environmental pollutant stages in the pulp and paper industry, here, the total chlorine-free (TCF) bleaching of poplar kraft pulp by applying Oxone and peroxide under alkaline conditions has been investigated. The pulp samples were bleached in two stages of Oxone () treatment using an A sequence (A: acid pretreatment), and then the treated pulps were bleached by peroxide (P) to achieve target brightness (about 80%). The influence of various reaction parameters such as alkali charge, temperature, reaction time, and bleaching agent dosage was optimized. The final achieved brightness was more than 78%. Accelerated aging experiments showed more stability in brightness for the Oxone treated pulp, because alkali Oxone bleaching stops thermal degradation. Similarly, the AP bleaching sequence was found to be effective in regaining some strength that had been lost during acidification of the pulp. Improvement in pulp strength made with acid treatment was achieved along with significant amount of lignin removal and it demonstrates the feasibility of Oxone in TCF bleaching. Furthermore, other results indicated the feasibility of Oxone bleaching as an environmentally favorable alternative TCF bleaching sequence, compared with elemental chlorine-free bleaching approaches and also other TCF bleaching sequences. Mohsen Miri, Ali Ghasemian, Hosein Resalati, and Farhad Zeinaly Copyright © 2015 Mohsen Miri et al. All rights reserved. A New Generation of Glycoconjugated Azo Dyes Based on Aminosugars Wed, 29 Jul 2015 16:14:30 +0000 The third generation of glycoconjugated azo dyes (GADs) was prepared linking monoazo dyes to 6-amino-6-deoxy-d-galactose or 6′amino-6′-deoxylactose through mixed amido-ester connections. The complementary conjugation reactions were studied using the succinyl derivative of either the acetal protected aminosugar or the azo dye. Target “naturalized” GADs were obtained after acid hydrolysis of the acetal protecting groups present on the sugar moiety. Lorenzo Guazzelli, Giorgio Catelani, and Felicia D’Andrea Copyright © 2015 Lorenzo Guazzelli et al. All rights reserved. Physicochemical Properties and Antioxidant Activity of Chitin and Chitosan Prepared from Pacific White Shrimp Waste Mon, 16 Feb 2015 11:43:18 +0000 Chitin and chitosan, valuable marine biopolymers, recovered from shrimp waste, are an abundant by-product of the shrimp processing industry in Vietnam, at an estimated 200000 metric tons per year. The obtained chitin and chitosan are characterized by their purity and functional properties. The polymers show good quality with low residual ash and protein content (<1%). The antioxidant potency of chitosan is evaluated by several different in vitro systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, total reducing power, and inhibition of lipid peroxidation. The DPPH free radical scavenging, total reducing power, and lipid peroxidation inhibition activities of chitosan at varying concentration (0.125 to 1.0 mg/mL) range from 3.7 to 16.8%, 0.05 to 0.15, and 1.7 to 15.1%, respectively. This study demonstrates that chitin and chitosan, of good quality and having characteristics compatible with a broad range of applications, can be prepared from white shrimp waste. Trang Si Trung and Huynh Nguyen Duy Bao Copyright © 2015 Trang Si Trung and Huynh Nguyen Duy Bao. All rights reserved. Structure of a Rhamnogalacturonan Fragment from Apple Pectin: Implications for Pectin Architecture Sun, 14 Dec 2014 10:06:18 +0000 A commercial apple pectin was sequentially digested with the cloned enzymes endopolygalacturonase, galactanase, arabinofuranosidase, xylogalacturonase, and rhamnogalacturonan hydrolase. The rhamnogalacturonan hydrolase-generated oligosaccharides were separated by ultrafiltration, anion exchange, and size-exclusion chromatography. Fractions from the ion exchange chromatography were pooled, lyophilized, and screened by MALDI-TOF MS. An oligosaccharide (RGP14P3) was identified and its structure, α-D-GalpA--α-L-Rhap--α-D-GalpA--α-L-Rhap--α-D-GalpA, determined by 1D and 2D NMR spectrometry. This oligosaccharide probably represents a direct connection between homogalacturonan and rhamnogalacturonan in pectin. Alternatively, it could indicate that the nonreducing end of rhamnogalacturonan starts with a galacturonic acid residue. Xiangmei Wu and Andrew Mort Copyright © 2014 Xiangmei Wu and Andrew Mort. All rights reserved. Kinetics and Mechanism of Micellar Catalyzed Oxidation of Dextrose by N-Bromosuccinimide in H2SO4 Medium Mon, 01 Dec 2014 00:10:00 +0000 Kinetics and mechanism of micellar catalyzed N-bromosuccinimide oxidation of dextrose in H2SO4 medium was investigated under pseudo-first-order condition temperature of 40°C. The results of the reactions studied over a wide range of experimental conditions show that NBS shows a first order dependence, fractional order, on dextrose and negative fractional order dependence on sulfuric acid. The determined stoichiometric ratio was 1 : 1 (dextrose : N-bromosuccinimide). The variation of Hg(OAC)2 and succinimide (reaction product) has insignificant effect on reaction rate. Effects of surfactants, added acrylonitrile, added salts, and solvent composition variation have been studied. The Arrhenius activation energy and other thermodynamic activation parameters are evaluated. The rate law has been derived on the basis of obtained data. A plausible mechanism has been proposed from the results of kinetic studies, reaction stoichiometry, and product analysis. The role of anionic and nonionic micelle was best explained by the Berezin’s model. Minu Singh Copyright © 2014 Minu Singh. All rights reserved. Thio-β-D-glucosides: Synthesis and Evaluation as Glycosidase Inhibitors and Activators Thu, 21 Aug 2014 11:15:02 +0000 Structurally simple 1-thio-β-D-glucopyranosides were synthesized and tested as potential inhibitors toward several fungal glycosidases from Aspergillus oryzae and Penicillium canescens. Significant selective inhibition was observed for α- and β-glucosidases, while a weak to moderate activation for α- and β-galactosidases. Andrey V. Samoshin, Irina A. Dotsenko, Nataliya M. Samoshina, Andreas H. Franz, and Vyacheslav V. Samoshin Copyright © 2014 Andrey V. Samoshin et al. All rights reserved. Twenty Traditional Algerian Plants Used in Diabetes Therapy as Strong Inhibitors of α-Amylase Activity Tue, 05 Aug 2014 12:17:50 +0000 In the present work, we have studied the inhibitory effects of aqueous and alcoholic extracts of six Algerian medicinal plants known by their therapeutic virtues against diabetes. The total phenolic compounds content, assayed using Folin-Ciocalteu’s reagent, of the samples ranged from 0.183 mg/g to 43.088 mg/g and from 1.197 mg/g to 7.445 mg/g, expressed as gallic acid equivalent (GAE), for the, respectively, whereas the total flavonoids concentrations, detected using 2% of the aluminium chloride, ranged from 0.41 mg/g to 11.613 mg/g and from 0.0097 mg/g to 1.591 mg/g, expressed as rutin equivalents (RE), for the aqueous and methanolic extracts, respectively. The major plants were found to inhibit enzymatic activities of Aspergillus oryzae-amylase in a concentration dependent manner. The values of the inhibition constants () have been determined according to the Dixon and Lineweaver-Burk methods. The results showed that the values were less than 55 ppm for the all extracts. A strong inhibition was found in the phenolic extract of Salvia officinalis with a of 8 ppm. Ihcen Khacheba, Amar Djeridane, and Mohamed Yousfi Copyright © 2014 Ihcen Khacheba et al. All rights reserved. One Step Photopolymerization of N, N-Methylene Diacrylamide and Photocuring of Carboxymethyl Starch-Silver Nanoparticles onto Cotton Fabrics for Durable Antibacterial Finishing Thu, 17 Jul 2014 09:28:53 +0000 The PI/UV system ((4-trimethyl ammonium methyl) benzophenone chloride/UV) was used to synthesize carboxymethyl starch- (CMS-) stabilized silver nanoparticles (AgNPs). AgNPs so prepared had round shape morphology with size of 1–7 nm. The prepared AgNPs were utilized to impart antibacterial finishing for cotton fabrics. The PI/UV system was further utilized to fix AgNPs onto cotton fabrics by photocrosslinking of AgNPs-CMS composite onto cotton fabrics to impart durable antibacterial properties. Effect of irradiation time and incorporating N, N-methylene diacrylamide (MDA) in different concentrations on antibacterial performance before and after repeated washing cycles was studied. S. aureus and E. coli were used to evaluate the antibacterial performance of finished fabrics. The antibacterial performance was directly proportional to the irradiation time and concentration of MDA but inversely proportional to the number of washing cycles. The inhibition zone of S. aureus and E. coli is the same although they are different in the cell wall structure and mode of action due to the nanosize structure formed. M. A. El-Sheikh and H. M. Ibrahim Copyright © 2014 M. A. El-Sheikh and H. M. Ibrahim. All rights reserved. New View to Obtain Dryer Food Foams with Different Polysaccharides and Soy Protein by High Ultrasound Wed, 26 Mar 2014 09:52:50 +0000 The objective of this work was to determine the effects of high intensity ultrasound application on the foaming properties of soy protein-polysaccharides mixed solutions. To this end, foaming parameters during foam formation were analyzed. The samples were sonicated for 20 min using ultrasonic processor Vibra Cell Sonics, and model VCX 750 at a frequency of 20 kHz and an amplitude of 20%. The foams were produced by a Foamscan instrument. The evolution of the bubble size change in the foam was also determined by a second CCD camera. For all foamed systems, at two pHs 3 and 7, Foam expansion and Relative Foam Conductivity showed a great increase after ultrasonic treatment. Other parameters studied did not show difference. On the other hand, Final Time of Foaming and the Total Gas Volume incorporation for foams formation were correlated with the Relative Foam Conductivity decrease and the Foam Expansion increase when HIUS were applied in every system. Comparative bubble size and shape during the foam formation according to the treatments and pH used confirmed the parameters results. Karina D. Martínez and Cecilio Carrera Sanchez Copyright © 2014 Karina D. Martínez and Cecilio Carrera Sanchez. All rights reserved. Role of Polysaccharides in Complex Mixtures with Soy Protein Hydrolysate on Foaming Properties Studied by Response Surface Methodology Tue, 04 Feb 2014 07:06:52 +0000 The complex mixture studied, a hydrolyzed soy protein (HSP), κ-carrageenan (κC), and an hydroxypropyl methylcellulose (HPMC), could be used as a foaming agent under refrigeration or heating conditions because of the presence of one polysaccharide (HPMC) that gels on heating and another (κC) that gels on cooling. The objective of this work was to study the role of these polysaccharides on foaming properties by whipping methods at heating conditions. For this purpose, response surface methodology was used to optimize the mixed product in foamed food systems. The obtained results showed that the combination of E4M, κC, and HSP is an adequate strategy to generate good foam capacity and stability at heating conditions. The huge stability increase of foams at heating conditions was ascribed to combined effect of polysaccharides: gelling property of E4M and the viscozieng character imparted by κC to continuous phase of foaming. Karina D. Martínez and Ana M. R. Pilosof Copyright © 2014 Karina D. Martínez and Ana M. R. Pilosof. All rights reserved. A Green Approach to Synthesize Silver Nanoparticles in Starch-co-Poly(acrylamide) Hydrogels by Tridax procumbens Leaf Extract and Their Antibacterial Activity Tue, 24 Dec 2013 15:04:59 +0000 A series of starch-co-poly(acrylamide) (starch-co-PAAm) hydrogels were synthesized by employing free radical redox polymerization. A novel green approach, Tridax procumbens (TD) leaf extract, was used for reduction of silver ions (Ag+) into silver nanoparticles in the starch-co-PAAm hydrogel network. The formation of silver nanoparticles was confirmed by UV-visible spectroscopy (UV-Vis), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (X-RD) studies. 22% of weight loss difference between hydrogel and silver nanocomposite hydrogel (SNCH) clearly indicates the formation of silver nanoparticles by TGA. TEM images indicate the successful incorporation of silver nanoparticles ranging from 5 to 10 nm in size and spherical in shape with a narrow size distribution. These developed SNCHs were used to study the antibacterial activity by inhibition zone method against gram-positive and gram-negative bacteria such as Bacillus and Escherichia coli. The results indicated that these SNCHs can be used potentially for biomedical applications. Siraj Shaik, Madhusudana Rao Kummara, Sudhakar Poluru, Chandrababu Allu, Jaffer Mohiddin Gooty, Chowdoji Rao Kashayi, and Marata Chinna Subbarao Subha Copyright © 2013 Siraj Shaik et al. All rights reserved. Synthesis and Antimicrobial Activity of Carbohydrate Based Schiff Bases: Importance of Sugar Moiety Thu, 12 Dec 2013 11:14:56 +0000 A series of D-glucosamine derivatives were synthesized (2–4) and evaluated for their antimicrobial activity. Some of the compounds investigated have shown significant antimicrobial activity against Gram-positive and Gram-negative bacterial strains as well as a few fungal strains. The results suggest that the presence of sugar moiety is necessary to biological activity. Helmoz R. Appelt, Julieta S. Oliveira, Roberto C. V. Santos, Oscar E. D. Rodrigues, Maura Z. Santos, Elisiane F. Heck, and Líria C. Rosa Copyright © 2013 Helmoz R. Appelt et al. All rights reserved. Combination of Natural and Thermosensitive Polymers in Flocculation of Fine Silica Dispersions Mon, 11 Nov 2013 15:44:46 +0000 A novel strategy for faster and better flocculation in solid-liquid separation processes is reported: the use of the natural polyelectrolyte chitosan (CH2500) in combination with the biocompatible thermosensitive polymer poly(N-vinylcaprolactam) (PNVCL). Silica dispersions (Aerosil OX50) were used as model and evaluated by means of analytical centrifuge, laser diffraction, and turbidimetry studies. Results show that the sedimentation velocity is doubled by addition of PNVCL and that at 45°C the density of the sediment is 33% higher, as compared to the use of CH2500 only. This results from the temperature sensitive behavior of PNVCL that phase-separate expelling water at temperatures higher than its LCST (32–34°C) leading to compaction of the flocs. By using this strategy the sediment is more compact, contains less water, and contains a very small amount of biodegradable CH2500 and biocompatible PNVCL. Angel Licea-Claverie, Simona Schwarz, Christine Steinbach, Sandra Montserrat Ponce-Vargas, and Sabine Genest Copyright © 2013 Angel Licea-Claverie et al. All rights reserved. Efficient Synthesis of Dispiropyrrolidines Linked to Sugars Sun, 10 Nov 2013 09:34:45 +0000 An expedient method for the synthesis of glyco-dispiropyrrolidines is reported through 1,3-dipolar cycloaddition reaction (1,3 DC reaction). The novel glycosyl dipolarophiles derived from D-glucose underwent neat [3+2] cycloaddition reaction with the azomethine ylides generated from 1,2-diketones and sarcosine to give the corresponding glycosidic heterocycles in good yields. Sirisha Nallamala and Raghavachary Raghunathan Copyright © 2013 Sirisha Nallamala and Raghavachary Raghunathan. All rights reserved. Synthesis and Application of Nanocrystalline-Cellulose-Supported Acid Ionic Liquid Catalyst in Pechmann Reaction Tue, 29 Oct 2013 14:21:46 +0000 Nanocrystalline-cellulose-supported acidic ionic liquid carrying SO3H functional group was prepared using nanocrystalline cellulose, imidazole and 1,4-butane sultone as the source chemicals. The prepared nanocrystalline-cellulose-supported ionic liquid catalyst was characterized by AFM and SEM and its catalytic activity in the reaction of resorcinol with ethyl acetoacetate was tested in a solvent-free condition. The effects of reaction time, reaction temperature, and the ratio of catalyst on the conversion of resorcinol were investigated. A variety of coumarin derivatives were obtained in good yield in the absence of solvent. Moslem Mansour Lakouraj, Nazanin Bagheri, and Vahid Hasantabar Copyright © 2013 Moslem Mansour Lakouraj et al. All rights reserved. Analgesic Activity of a Glucan Polysaccharide Isolated from Agaricus blazei Murill Thu, 19 Sep 2013 16:10:55 +0000 A water soluble polysaccharide and its selective precipitated fractions (F1, F2, and F3) were isolated from hot water extract of fruiting bodies of Agaricus blazei Murril known as Agaricus brasiliensis to evaluate the analgesic activity of the materials in Swiss mice. The isolated material and its fractions were characterized by two-dimensional COSY and HMQC spectra as β-(1→6)-α-(1→4)-glucan-bound-protein polysaccharide constituted mainly by β-(1→6) glucan. The glucan-protein polysaccharide and its fractions were analyzed in relation to the protein, carbohydrate, and mineral elements contents. The analysis of the glucan-protein complex revealed a total carbohydrate content of 36.95% and protein conjugated content of 17.24%. The mineral elements found in larger proportion were K, Na, Ca, P, and Zn. The analgesic activity bioassay of the β-(1→6)-α-(1→4)-glucan bound-protein polysaccharide and its fractions in Swiss mice indicated a significant effect. Maria Leônia C. Gonzaga, Thiago M. F. Menezes, José R. R. de Souza, Nágila M. P. S. Ricardo, Ana L. P. Freitas, and Sandra de A. Soares Copyright © 2013 Maria Leônia C. Gonzaga et al. All rights reserved. Synthesis and Characterization of Acrylic Acid-g-(-Carrageenan) Copolymer and Study of Its Application Tue, 11 Jun 2013 11:14:34 +0000 The effects of concentrations of peroxymonosulphate, mercaptosuccinic acid, hydrogen ion, acrylic acid, and carrageenan on grafting parameters were studied to find out the maximum grafting ratio. The corresponding values were found to be , , ,  mol dm−3, and  g dm−3, respectively. The optimal reaction time duration and reaction temperature were found to be 120 min and 40°C, respectively. The effect of hydrogen ion variation from 5.0 up to  mol dm−3 shows prompt changes on grafting parameter. The grafted copolymer was found more thermally stable than the ungrafted substrate. Also the grafted copolymer absorbed more water, namely hazardous metal cations. Hg2+, Pb2+, and Cd2+, showed better flocculation behavior than carrageenan. Arti Srivastava and Rajesh Kumar Copyright © 2013 Arti Srivastava and Rajesh Kumar. All rights reserved. Effect of Molecular Sizes of Chondroitin Sulfate on Interaction with L-Selectin Wed, 08 May 2013 13:36:56 +0000 Chondroitin sulfate (CS) is a glycosaminoglycan (GAG) side chain of proteoglycans (PGs) which are widely distributed in the extracellular matrix and at cell surface. CS shows a highly structural diversity in not only molecular weight (MW) but sulfonation pattern. CS has been reported to exert anti-inflammatory activity by having effects on cytokine production by helper T cells. In this study, we focused on the structures of CS chains, especially MW of CS, and investigated effect of the different MW of CS on binding affinity with L-selectin and cytokine production by murine splenocytes. Firstly, we fractionated CS by employing gel filtration chromatography and obtained several CS fractions with different MW. Then the interaction between fractionated CS and L-selectin was analyzed by surface plasmon resonance (SPR). Finally, the influence of MW of CS on cytokine production by murine splenocytes was investigated in vitro. The results showed that interferon-gamma production was significantly increased by mouse splenocytes cocultivated with CS. On the contrary, CS inhibited interleukin 5 production by murine splenocytes depending on MW of the cocultivated CS. These results strongly indicate the existence of the optimal molecular size for an anti-inflammatory effect of CS through cytokine production by murine splenocytes. Naoko Igarashi, Atsuko Takeguchi, Shinobu Sakai, Hiroshi Akiyama, Kyohei Higashi, and Toshihiko Toida Copyright © 2013 Naoko Igarashi et al. All rights reserved. Certain Rheological Aspects of Functionalized Guar Gum Wed, 24 Apr 2013 13:30:50 +0000 Guar gum and its derivatives are highly important industrial hydrocolloids as they find applications in various industrial sectors. Guar is a polymer of high molecular weight and its aqueous solutions exhibit unique rheological properties, which has led to its wide acceptance by the industry. In certain industrial applications low molecular weight guar and its derivatives are needed, and conventionally chemical depolymerisation of guar is carried out for this purpose. Radiation processing is a novel and green technology for carrying out depolymerization and can be an ideal substitute for chemical depolymerisation technique. In order to study the effect of radiation on guar derivatives, three types of derivatives have been taken in the present study: carboxymethyl, hydroxyethyl, and methyl guar. The effect of 1–50 KGy radiation dose on the rheological behavior of these derivatives has been studied, and the results have been described in the present paper. The effect on storage and loss modulus with respect to frequency and effect on viscosity with respect to shear rate have been discussed in detail. Meenu Kapoor, Dhriti Khandal, Ruchi Gupta, Pinklesh Arora, Geetha Seshadri, Saroj Aggarwal, and Rakesh Kumar Khandal Copyright © 2013 Meenu Kapoor et al. All rights reserved. Development and Characterization of Semi-IPN Silver Nanocomposite Hydrogels for Antibacterial Applications Thu, 21 Mar 2013 13:45:16 +0000 Sodium carboxymethyl cellulose/poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) semi-interpenetrating polymer network (semi-IPN) hydrogels were prepared by using free radical polymerization technique. Silver nanoparticles were formed by reduction of silver nitrate in semi-IPN hydrogels with sodium borohydrate at room temperature. UV-visible spectroscopy, thermogravimetrical analysis, X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize the formation of silver nanoparticles in hydrogels. SEM images indicated clearly the formation of group of silver nanoparticles with size range of 10–20 nm. The sizes of silver nanoparticles were also supported by transmission electron microscopy results. The semi-IPN silver nanocomposite hydrogels reported here might be a potentially smart material in the range of applications of antibacterial activity. A. Chandra Babu, M. N. Prabhakar, A. Suresh Babu, B. Mallikarjuna, M. C. S. Subha, and K. Chowdoji Rao Copyright © 2013 A. Chandra Babu et al. All rights reserved. Analysis by Vibrational Spectroscopy of Seaweed Polysaccharides with Potential Use in Food, Pharmaceutical, and Cosmetic Industries Tue, 12 Mar 2013 15:15:20 +0000 Polysaccharides present in several seaweeds (Kappaphycus alvarezii, Calliblepharis jubata, and Chondrus crispus—Gigartinales, Rhodophyta; Gelidium corneum and Pterocladiella capillacea—Gelidiales, Rhodophyta; Laurencia obtusa—Ceramiales, Rhodophyta; Himanthalia elongata, Undaria pinnatifida, Saccorhiza polyschides, Sargassum vulgare, and Padina pavonica—Phaeophyceae, Ochrophyta) are analyzed by spectroscopic techniques. The nature of the polysaccharides (with extraction and without any type of extraction) present in these seaweeds was determined with FTIR-ATR and FT-Raman analysis of extracted phycocolloids and ground dry seaweed. Leonel Pereira, Saly F. Gheda, and Paulo J. A. Ribeiro-Claro Copyright © 2013 Leonel Pereira et al. All rights reserved. The Effect of Tribomechanical Micronization and Activation on Rheological, Thermophysical, and Some Physical Properties of Tapioca Starch Tue, 12 Mar 2013 09:18:40 +0000 The aim of this research was to investigate the effect of tribomechanical treatments on rheological, thermophysical, and some physical properties of tapioca starch. Samples of tapioca starch were treated using laboratory equipment for tribomechanical micronization and activation (TMA equipment). Before and after the TMA treatment, analysis of the particle size and particle size distribution was carried out, in addition to scanning electron micrography in tapioca starch. Scanning electron micrography showed that tribomechanical processing of tapioca starch resulted in breaking accumulations of starch granules in the form of granules. Pasting parameters have shown that maximal viscosities of model starch suspension have been decreasing after tribomechanical treatment. On the basis of gelatinization curves, it can be concluded that there are changes in the gelatinization point after treatment, and there is decrease in enthalpy of gelatinization for model suspension. After tribomechanical treatment, changes in physical properties of starch suspensions were determined, as well as specific swelling capacity, solubility index, and turbidity of tapioca starch suspensions. Zoran Herceg, Verica Batur, Anet Režek Jambrak, Tomislava Vukušić, Ines Gmajnički, and Igor Špoljarić Copyright © 2013 Zoran Herceg et al. All rights reserved. Production Methods for Hyaluronan Tue, 05 Mar 2013 08:53:14 +0000 Hyaluronan is a polysaccharide with multiple functions in the human body being involved in creating flexible and protective layers in tissues and in many signalling pathways during embryonic development, wound healing, inflammation, and cancer. Hyaluronan is an important component of active pharmaceutical ingredients for treatment of, for example, arthritis and osteoarthritis, and its commercial value far exceeds that of other microbial extracellular polysaccharides. Traditionally hyaluronan is extracted from animal waste which is a well-established process now. However, biotechnological synthesis of biopolymers provides a wealth of new possibilities. Therefore, genetic/metabolic engineering has been applied in the area of tailor-made hyaluronan synthesis. Another approach is the controlled artificial (in vitro) synthesis of hyaluronan by enzymes. Advantage of using microbial and enzymatic synthesis for hyaluronan production is the simpler downstream processing and a reduced risk of viral contamination. In this paper an overview of the different methods used to produce hyaluronan is presented. Emphasis is on the advancements made in the field of the synthesis of bioengineered hyaluronan. Carmen G. Boeriu, Jan Springer, Floor K. Kooy, Lambertus A. M. van den Broek, and Gerrit Eggink Copyright © 2013 Carmen G. Boeriu et al. All rights reserved. Latent Fingerprint Enhancement Using Tripolyphosphate-Chitosan Microparticles Thu, 21 Feb 2013 12:04:06 +0000 Chitosan has been widely used in the preparation of microparticles for drug delivery; however, it has not been considered in forensic applications. Tripolyphosphate- (TPP-) chitosan microparticles were formed using ionotropic gelation in the presence of a coloured dye and deposited onto latent fingerprints enabling fingerprint identification. Issa M. A. Il Dueik and Gordon A. Morris Copyright © 2013 Issa M. A. Il Dueik and Gordon A. Morris. All rights reserved. Acetylation of Wood Flour from Four Wood Species Grown in Nigeria Using Vinegar and Acetic Anhydride Thu, 10 Jan 2013 18:30:36 +0000 Effect of acetylation on pretreated wood flour of four different wood species, Boabab (Adansonia digitata), Mahoganny (Daniella oliveri), African locust bean (Parkia biglobosa) and Beech wood (Gmelina arborea), had been investigated. The first batch of wood species were acetylated using acetic anhydride while the second batch were acetylated with commercial vinegar. Both experiments were conducted in the presence of varying amount of CaCl2 as catalyst and at temperature of 120°C for 3 h. The success of acetylation was determined based on Weight Percent Gain for each sample treated with either chemicals used. FT-IR, a veritable tool was used for the analysis of both treated and untreated samples to further investigate the success of acetylation. The results showed the presence of important band such as carbonyl absorptions at 1743, 1744, 1746, 1731, 1718 and 1696 cm−1 as appeared separately in the spectra of acetylated samples, confirming esterification occurred. The purpose of this work was to investigate the applicability of vinegar for acetylation of lignocellulosic fibers. Blends/composites were prepared by solution casting and their kinetics investigated in distilled water. The results indicated they could be used in outdoor applications such as, decking and packaging. Yakubu Azeh, Gabriel Ademola Olatunji, Cheku Mohammed, and Paul Andrew Mamza Copyright © 2013 Yakubu Azeh et al. All rights reserved. Factors Involved in the In Vitro Fermentability of Short Carbohydrates in Static Faecal Batch Cultures Tue, 18 Dec 2012 07:50:36 +0000 In recent years, research has focused on the positive effects of prebiotics on intestinal health and gut microbiota. The relationship between their chemical structure and their fermentation pattern by human intestinal microbiota is still not well understood. The aim of this study was to improve understanding of this relationship and identify factors that may be used to design galactooligosaccharides that reach more distal regions than commercial prebiotics which mainly target the proximal colon. The following factors were investigated: monomer type, linkage, substitution, and degree of polymerisation. Total organic acid production from sugars by faecal bacteria was fitted to a model which allowed an estimate of the time when half of the maximal organic acid concentration was reached (T50) in static faecal batch cultures. The different factors can be grouped by their effectiveness at prolonging fermentation time as follows: substitution is most effective, with methylgalactose, -galactose-pentaacetate, D-fucose, and galactitol fermented more slowly than D-galactose. Monomers and linkage also influence fermentation time, with L rhamnose, arabinose, melezitose, and xylose being fermented significantly slower than D-glucose (), maltose, isomaltose, cellobiose, and gentiobiose showing that Glc1-6Glc and Glc1-4Glc were utilised slowest. Chain length had the smallest effect on fermentation time. Eva Gietl, Wim Mengerink, Jaap de Slegte, Glenn Gibson, Robert Rastall, and Ellen van den Heuvel Copyright © 2012 Eva Gietl et al. All rights reserved. New 1,2,3-Triazole Iminosugars Derivatives Using Click Chemistry Wed, 12 Dec 2012 15:01:11 +0000 The click concept refers ease, efficient, and the selective chemicals transformations. In this study, a novel regiospecific copper (I)-catalyzed 1, 3-dipolar of terminal alkynes to azide provided a practicable synthetic pathway of triazole iminosugars derivatives. A series of new triazole-pyrrolidinols are reported in good yield. Chahrazed Benhaoua Copyright © 2012 Chahrazed Benhaoua. All rights reserved.