Showing papers on "Chitin published in 2010"

Application of Spectroscopic Methods for Structural Analysis of Chitin and Chitosan

Abstract: Chitin, the second most important natural polymer in the world, and its N-deacetylated derivative chitosan, have been identified as versatile biopolymers for a broad range of applications in medicine, agriculture and the food industry. Two of the main reasons for this are firstly the unique chemical, physicochemical and biological properties of chitin and chitosan, and secondly the unlimited supply of raw materials for their production. These polymers exhibit widely differing physicochemical properties depending on the chitin source and the conditions of chitosan production. The presence of reactive functional groups as well as the polysaccharide nature of these biopolymers enables them to undergo diverse chemical modifications. A complete chemical and physicochemical characterization of chitin, chitosan and their derivatives is not possible without using spectroscopic techniques. This review focuses on the application of spectroscopic methods for the structural analysis of these compounds.

Two LysM receptor molecules, CEBiP and OsCERK1, cooperatively regulate chitin elicitor signaling in rice

Abstract: Chitin is a major molecular pattern for various fungi, and its fragments, chitin oligosaccharides, are known to induce various defense responses in plant cells. A plasma membrane glycoprotein, CEBiP (chitin elicitor binding protein) and a receptor kinase, CERK1 (chitin elicitor receptor kinase) (also known as LysM-RLK1), were identified as critical components for chitin signaling in rice and Arabidopsis, respectively. However, it is not known whether each plant species requires both of these two types of molecules for chitin signaling, nor the relationships between these molecules in membrane signaling. We report here that rice cells require a LysM receptor-like kinase, OsCERK1, in addition to CEBiP, for chitin signaling. Knockdown of OsCERK1 resulted in marked suppression of the defense responses induced by chitin oligosaccharides, indicating that OsCERK1 is essential for chitin signaling in rice. The results of a yeast two-hybrid assay indicated that both CEBiP and OsCERK1 have the potential to form hetero- or homo-oligomers. Immunoprecipitation using a membrane preparation from rice cells treated with chitin oligosaccharides suggested the ligand-induced formation of a receptor complex containing both CEBiP and OsCERK1. Blue native PAGE and chemical cross-linking experiments also suggested that a major portion of CEBiP exists as homo-oligomers even in the absence of chitin oligosaccharides.

Chitosan in plant protection

Abstract: Chitin and chitosan are naturally-occurring compounds that have potential in agriculture with regard to controlling plant diseases. These molecules were shown to display toxicity and inhibit fungal growth and development. They were reported to be active against viruses, bacteria and other pests. Fragments from chitin and chitosan are known to have eliciting activities leading to a variety of defense responses in host plants in response to microbial infections, including the accumulation of phytoalexins, pathogen-related (PR) proteins and proteinase inhibitors, lignin synthesis, and callose formation. Based on these and other proprieties that help strengthen host plant defenses, interest has been growing in using them in agricultural systems to reduce the negative impact of diseases on yield and quality of crops. This review recapitulates the properties and uses of chitin, chitosan, and their derivatives, and will focus on their applications and mechanisms of action during plant-pathogen interactions.

Chitins and chitosans as immunoadjuvants and non-allergenic drug carriers.

Abstract: Due to the fact that some individuals are allergic to crustaceans, the presumed relationship between allergy and the presence of chitin in crustaceans has been investigated. In vivo, chitin is part of complex structures with other organic and inorganic compounds: in arthropods chitin is covalently linked to proteins and tanned by quinones, in fungi it is covalently linked to glucans, while in bacteria chitin is diversely combined according to Gram(+/-) classification. On the other hand, isolated, purified chitin is a plain polysaccharide that, at the nano level, presents itself as a highly associated structure, recently refined in terms of regularity, nature of bonds, crystallinity degree and unusual colloidal behavior. Chitins and modified chitins exert a number of beneficial actions, i.e., (i) they stimulate macrophages by interacting with receptors on the macrophage surface that mediate the internalization of chitin particles to be degraded by lysozyme and N-acetyl-beta-glucosaminidase (such as Nod-like, Toll-like, lectin, Dectin-1, leukotriene 134 and mannose receptors); (ii) the macrophages produce cytokines and other compounds that confer non-specific host resistance against bacterial and viral infections, and anti-tumor activity; (iii) chitin is a strong Th1 adjuvant that up-regulates Th1 immunity induced by heat-killed Mycobacterium bovis, while down- regulating Th2 immunity induced by mycobacterial protein; (iv) direct intranasal application of chitin microparticles into the lung was also able to significantly down-regulate allergic response to Dermatophagoids pteronyssinus and Aspergillus fumigatus in a murine model of allergy; (v) chitin microparticles had a beneficial effect in preventing and treating histopathologic changes in the airways of asthmatic mice; (vi) authors support the fact that chitin depresses the development of adaptive type 2 allergic responses. Since the expression of chitinases, chitrotriosidase and chitinase-like proteins is greatly amplified during many infections and diseases, the common feature of chitinase-like proteins and chitinase activity in all organisms appears to be the biochemical defense of the host. Unfortunately, conceptual and methodological errors are present in certain recent articles dealing with chitin and allergy, i.e., (1) omitted consideration of mammalian chitinase and/or chitotriosidase secretion, accompanied by inactive chitinase-like proteins, as an ancestral defensive means against invasion, capable to prevent the insurgence of allergy; (2) omitted consideration of the fact that the mammalian organism recognizes more promptly the secreted water soluble chitinase produced by a pathogen, rather than the insoluble and well protected chitin within the pathogen itself; (3) superficial and incomplete reports and investigations on chitin as an allergen, without mentioning the potent allergen from crustacean flesh, tropomyosine; (4) limited perception of the importance of the chemical/biochemical characteristics of the isolated chitin or chitosan for the replication of experiments and optimization of results; and (5) lack of interdisciplinarity. There is quite a large body of knowledge today on the use of chitosans as biomaterials, and more specifically as drug carriers for a variety of applications: the delivery routes being the same as those adopted for the immunological studies. Said articles, that devote attention to the safety and biocompatibility aspects, never reported intolerance or allergy in individuals and animals, even when the quantities of chitosan used in single experiments were quite large. Therefore, it is concluded that crab, shrimp, prawn and lobster chitins, as well as chitosans of all grades, once purified, should not be considered as "crustacean derivatives", because the isolation procedures have removed proteins, fats and other contaminants to such an extent as to allow them to be classified as chemicals regardless of their origin.

Chitosan/double-stranded RNA nanoparticle-mediated RNA interference to silence chitin synthase genes through larval feeding in the African malaria mosquito (Anopheles gambiae)

Abstract: The purpose of this study was to examine whether the expression of two chitin synthase genes, AgCHS1 and AgCHS2, can be repressed by chitosan/AgCHS dsRNA-based nanoparticles through larval feeding in Anopheles gambiae. The AgCHS1 transcript level and chitin content were reduced by 62.8 and 33.8%, respectively, in the larvae fed on chitosan/AgCHS1 dsRNA nanoparticles compared with those of the control larvae fed on chitosan/GFP dsRNA nanoparticles. Our study suggested for the first time that RNA interference (RNAi) in mosquito larvae is systemic, and demonstrated that the larvae fed on the nanoparticles assembled from AgCHS1 and AgCHS2 dsRNA increased larval susceptibilities to diflubenzuron, and calcofluor white (CF) or dithiothreitol, respectively. These results suggest great potential for using such a nanoparticle-based RNAi technology for high-throughput screening of gene functions and for developing novel strategies for pest management.

Chitin Research Revisited

Abstract: Two centuries after the discovery of chitin, it is widely accepted that this biopolymer is an important biomaterial in many aspects. Numerous studies on chitin have focused on its biomedical applications. In this review, various aspects of chitin research including sources, structure, biosynthesis, chitinolytic enzyme, chitin binding protein, genetic engineering approach to produce chitin, chitin and evolution, and a wide range of applications in bio- and nanotechnology will be dealt with.

Applications of Chitin and Its Derivatives in Biological Medicine

Abstract: Chitin and its derivatives—as a potential resource as well as multiple functional substrates—have generated attractive interest in various fields such as biomedical, pharmaceutical, food and environmental industries, since the first isolation of chitin in 1811. Moreover, chitosan and its chitooligosaccharides (COS) are degraded products of chitin through enzymatic and acidic hydrolysis processes; and COS, in particular, is well suited for potential biological application, due to the biocompatibility and nontoxic nature of chitosan. In this review, we investigate the current bioactivities of chitin derivatives, which are all correlated with their biomedical properties. Several new and cutting edge insights here may provide a molecular basis for the mechanism of chitin, and hence may aid its use for medical and pharmaceutical applications.

Chitin deacetylases: properties and applications.

Abstract: Chitin deacetylases, occurring in marine bacteria, several fungi and a few insects, catalyze the deacetylation of chitin, a structural biopolymer found in countless forms of marine life, fungal cell and spore walls as well as insect cuticle and peritrophic matrices. The deacetylases recognize a sequence of four GlcNAc units in the substrate, one of which undergoes deacetylation: the resulting chitosan has a more regular deacetylation pattern than a chitosan treated with hot NaOH. Nevertheless plain chitin is a poor substrate, but glycolated, reprecipitated or depolymerized chitins are good ones. The marine Vibrio sp. colonize the chitin particles and decompose the chitin thanks to the concerted action of chitinases and deacetylases, otherwise they could not tolerate chitosan, a recognized antibacterial biopolymer. In fact, chitosan is used to prevent infections in fishes and crustaceans. Considering that chitin deacetylases play very important roles in the biological attack and defense systems, they may find applications for the biological control of fungal plant pathogens or insect pests in agriculture and for the biocontrol of opportunistic fungal human pathogens.

Chitin, chitosan, oligosaccharides and their derivatives : biological activities and applications

Abstract: THE SOURCES AND PRODUCTION OF CHITIN AND CHITOSAN DERIVATIVES Chitin and Chitosan from Terrestrial Organisms Nitar Nwe, Tetsuya Furuike, and Hiroshi Tamura Chitin and Chitosan from Marine Organisms Wolfram M. Bruck, John W. Slater, and Brian F. Carney Chitin and Chitosan from Microorganisms Zorica Knezevic-Jugovic, Zivomir Petronijevic, and Andrija Smelcerovic Enzymatic Production of Chitin from Crustacean Shell Waste Gyung-Hyun Jo, Ro-Dong Park, and Woo-Jin Jung Continuous Production of Chitooligosaccharides by Enzymatic Hydrolysis Se-Kwon Kim and Jae-Young Je Biosynthesis of Cellulose-Chitosan Composite Muenduen Phisalaphong, Nirun Jatupaiboon, and Jeerun Kingkaew PHYSICAL AND CHEMICAL ASPECTS OF CHITIN AND CHITOSAN DERIVATIVES Chemical Derivatization of Chitosan for Plasmid DNA Delivery: Present and Future Wing-Fu Lai and Marie Chin-Mi Lin X-Ray Diffraction Studies of Chitin, Chitosan, and Their Derivatives Waldemar Maniukiewicz Mechanical Properties of Chitosan and Chitosan-Poly(Vinyl Alcohol) Blend Films Masaru Matsuo, Yumiko Nakano, Teruo Nakashima, and Yuezhen Bin Electrostatic Properties of Chitosan Won Jong Kim Applications of Mass Spectrometry to Analyze Structure and Bioactivity of Chitooligosaccharides Martin G. Peter and Marcos N. Eberlin The Use of Various Types of NMR and IR Spectroscopy for Structural Characterization of Chitin and Chitosan Mohammad Reza Kasaai STRUCTURAL MODIFICATIONS OF CHITIN AND CHITOSAN DERIVATIVES Chemical Modifications of Chitosan Intended for Biomedical Applications Mani Prabaharan and Ashutosh Tiwari Enzymatic Modifications of Chitin and Chitosan Yong Zhao, Wan-Taek Ju, and Ro-Dong Park BIOLOGICAL ACTIVITIES OF CHITIN AND CHITOSAN DERIVATIVES Antimicrobial Activity of Chitin, Chitosan, and Their Oligosaccharides Joydeep Dutta and Pradip Kumar Dutta Anti-Inflammatory Activity of Chitin, Chitosan, and Their Derivatives Moon-Moo Kim and Se-Kwon Kim Chitosan Scaffolds for Bone Regeneration Riccardo A.A. Muzzarelli Antioxidative Activity of Chitin, Chitosan, and Their Derivatives Pyo-Jam Park, Sushruta Koppula, and Se-Kwon Kim Effects of Chitin, Chitosan, and Their Derivatives on Human Hemostasis Se-Kwon Kim and Won-Kyo Jung Antihypertensive Actions of Chitosan and Its Derivatives Jae-Young Je and Chang-Bum Ahn Anticancer Activity and Therapeutic Applications of Chitosan Nanoparticles Hang T. Ta, Dave E. Dunstan, and Crispin R. Dass Antidiabetic Activity and Cholesterol-Lowering Effect Chang-Suk Kong and Se-Kwon Kim BIOMEDICAL APPLICATIONS OF CHITIN AND CHITOSAN DERIVATIVES Chitin/Chitosan Oligosaccharides: Effective Substrates for Functional Analysis of Chitinases/Chitosanases Takayuki Ohnuma and Tamo Fukamizo Low-Molecular-Weight Water-Soluble Chitosan with Free Amine Group for Drug Delivery Mi-Kyeong Jang and Jae-Woon Nah Chitosan/Chitosan Derivatives as Carriers and Immunoadjuvants in Vaccine Delivery Suresh P. Vyas, Rishi Paliwal, and Shivani R. Paliwal Chitosan-Conjugated DNA Nanoparticle Delivery Systems for Gene Therapy R. Jayakumar, K. P. Chennazhi, S. V. Nair, Tetsuya Furuike, and Hiroshi Tamura Chitinolytic Enzymes from the Moderately Thermophilic Bacterium Ralstonia sp. A-471: Characterization and Application Mitsuhiro Ueda Chitosan and Chitosan Derivatives as DNA and siRNA Carriers Hu-Lin Jiang, Yun-Jaie Choi, Myung-Haing Cho, and Chong-Su Cho Metabolic Pathway of Chitin and Its Oligosaccharides in Marine Bacterium Vibrios Jae Kweon Park, Nemat O. Keyhani, and Saul Roseman Medical Applications of Chitin and Chitosan: Going Forward Eugene Khor Radiation Functionalization and Applications of Chitosan and Its Derivatives Maolin Zhai, Long Zhao, Ling Huang, Ling Xu, Liyong Yuan, and Min Wang Applications of Chitosan Oligosaccharide and Glucosamine in Dentistry Yoshihiko Hayashi Applications of Chitosan and Its Derivatives in Veterinary Medicine Sevda S,enel INDUSTRIAL APPLICATIONS OF CHITIN AND CHITOSAN DERIVATIVES Separation Membranes from Chitin and Chitosan Derivatives Tadashi Uragami Hydrophobically Modified Acylated Chitosan Particles for Drug Delivery Applications: An Overview R. Shelma and Chandra P. Sharma Chitin, Chitosan, and Their Derivatives in Beverage Industry Aurelie Bornet and Pierre-Louis Teissedre Chitin Nanofibrils and Their Derivatives as Cosmeceuticals P. Morganti Chitin, Chitosan, and Their Oligosaccharides in Food Industry Janak K. Vidanarachchi, Maheshika S. Kurukulasuriya, and Se-Kwon Kim Chitin/Chitosan and Derivatives for Wastewater Treatment P. N. Sudha AGRICULTURAL AND BIOTECHNOLOGY APPLICATIONS OF CHITIN AND CHITOSAN AND THEIR DERIVATIVES Chitin, Chitosan Derivatives Induced the Production of Secondary Metabolites and Plant Development through In Vitro and In Vivo Techniques Abdul Bakrudeen Ali Ahmed and Se-Kwon Kim Mechanism and Application of Chitin/Chitosan and Their Derivatives in Plant Protection Heng Yin and Yuguang Du Enhancing Crop Production with Chitosan and Its Derivatives Nguyen Anh Dzung

Extraction and Characterization of Chitin, Chitosan, and Protein Hydrolysates Prepared from Shrimp Waste by Treatment with Crude Protease from Bacillus cereus SV1

Abstract: Chitin is a polysaccharide found in abundance in the shell of crustaceans. In this study, the protease from Bacillus cereus SV1 was applied for chitin extraction from shrimp waste material of Metapenaeus monoceros. A high level of deproteinization 88.8% +/- 0.4 was recorded with an E/S ratio of 20. The demineralization was completely achieved within 6 h at room temperature in HCl 1.25 M, and the residual content of calcium in chitin was below 0.01%. (13)C CP/MAS-NMR spectral analysis of chitin prepared by the enzymatic deproteinization of shrimp wastes was found to be similar to that obtained by alkaline treatment and to the commercial alpha-chitin. The degree of N-acetylation, calculated from the spectrum, was 89.5%. Chitin obtained by treatment with crude protease from B. cereus was converted to chitosan by N-deacetylation, and the antibacterial activity of chitosan solution against different bacteria was investigated. Results showed that chitosan solution at 50 mg/mL markedly inhibited the growth of most Gram-negative and Gram-positive bacteria tested. Furthermore, the antioxidant potential of the protein hydrolysates obtained during enzymatic isolation of chitin was evaluated using various in vitro assays. All the samples exerted remarkable antioxidant activities. These results suggest that enzymatic deproteinization of the shrimp shell wastes, using B. cereus SV1 protease, could be applicable to the chitin production process.

Different Functions of the Insect Soluble and Membrane-Bound Trehalase Genes in Chitin Biosynthesis Revealed by RNA Interference

Abstract: Background Trehalase, an enzyme that hydrolyzes trehalose to yield two glucose molecules, plays a pivotal role in various physiological processes. In recent years, trehalase proteins have been purified from several insect species and are divided into soluble (Tre-1) and membrane-bound (Tre-2) trehalases. However, no functions of the two trehalases in chitin biosynthesis in insects have yet been reported.

Structure and function of enzymes acting on chitin and chitosan

Abstract: Enzymatic conversions of chitin and its soluble, partially deacetylated derivative chitosan are of great interest. Firstly, chitin metabolism is an important process in fungi, insects and crustaceans. Secondly, such enzymatic conversions may be used to transform an abundant biomass to useful products such as bioactive chito-oligosaccharides. Enzymes acting on chitin and chitosan are abundant in nature. Here we review current knowledge on the structure and function of enzymes involved in the conversion of these polymeric substrates: chitinases (glycoside hydrolase families 18 & 19), chitosanases (glycoside hydrolase families 8, 46, 75 & 80) and chitin deacetylases (carbohydrate esterase family 4).

Dissolution Behavior of Chitin in Ionic Liquids

Abstract: The dissolution behavior of chitin in a series of ionic liquids containing alkylimidazolium chloride, alkylimidazolium dimethyl phosphate, and 1-allyl-3-methyl-imidazolium acetate has been studied. Chitin with a low degree of acetylation and low molecular weight can be readily dissolved in ionic liquids, while those with a high degree of acetylation can also be dissolved in ionic liquids with various critical solution temperatures (CST) mainly depending on the structure of the chitin and the ionic liquids. The results indicated that the dissolution behavior of chitin in ionic liquids was affected by the degree of acetylation (DA), the crystallinity, and the molecular weights of chitin, as well as the nature of the anion of the ionic liquid.

Promotion of efficient Saccharification of crystalline cellulose by Aspergillus fumigatus Swo1.

Abstract: Cellulose is the primary polysaccharide of plant cell wall and the most abundant renewable biomass resource. Biological degradation of cellulose to soluble sugars has long been considered an alternative to the use of starch feedstocks for bioethanol production. Natural cellulose is an ordered, linear polymer of thousands of d-glucose residues linked by β-1,4-glucosidic bonds. Spontaneous crystallization of cellulose molecules due to chemical uniformity of glucose units and the high degree of hydrogen bonding in cellulose can often result in the formation of tightly packed microfibrils (8), which remain inaccessible to cellulolytic enzymes. No single enzyme is able to hydrolyze crystalline cellulose microfibrils completely. Synergistic effects of cellulase mixtures on crystalline cellulose degradation are well known (1, 7, 21). Nevertheless, cost-competitive technology for overcoming the recalcitrance of cellulosic biomass to enhance enzymatic saccharification is still a major impediment to the utilization of cellulosic materials in bioenergy generation. Expansins are plant cell wall proteins that cause cell wall enlargement by a unique loosening effect in an acid-induced manner (15, 20). They are also involved in many physiological processes where cell wall extension occurs, such as pollination, fruit ripening, organ abscission, and seed germination (13, 14). It has been proposed that plant expansins disrupt hydrogen bonding between cellulose microfibrils and other cell wall polysaccharides without hydrolytic activity, causing sliding of cellulose fibers or expansion of the cell wall (18, 19, 27). Swollenin, an expansin-like protein, was isolated and characterized from the cellulolytic filamentous fungus Trichoderma reesei. It has a bimodular structure consisting of a carbohydrate-binding module family 1 (CBM1) domain and an expansin-like domain connected by a linker region rich in serine and threonine. Swollenin exhibits disruption activity on cellulosic materials such as cotton and algal cell walls without releasing any detectable reducing sugars (23). However, effects of cellulose disruption activity on degradation/saccharification of crystalline cellulose have not yet been reported. Here, we report cloning a swollenin-like gene (designated Afswo1) from the filamentous fungus Aspergillus fumigatus. We also report its production by Aspergillus oryzae and characterization of the purified AfSwo1.