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Krzysztof Brzozowski

Bio: Krzysztof Brzozowski is an academic researcher from University of Gdańsk. The author has contributed to research in topics: Trypsin inhibitor & Two-dimensional nuclear magnetic resonance spectroscopy. The author has an hindex of 7, co-authored 21 publications receiving 844 citations.

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Journal ArticleDOI
TL;DR: A complete chemical and physicochemical characterization of chitin, chitosan and their derivatives is not possible without using spectroscopic techniques, so this review focuses on the application of Spectroscopic methods for the structural analysis of these compounds.
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.

848 citations

Journal ArticleDOI
TL;DR: The substrate specificity and selectivity study of the protease is described, performed by the combinatorial approach, and two peptide aldehydes were synthesized and (Abz-Arg-Gln-Asp-Arg(Lys)-H) were found to be an effective HAT inhibitor, working in nanomolar range with inhibition constant 54nM and 112nM, respectively.

24 citations

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TL;DR: The most suitable and specific method of chitosan determination was 13 C NMR based on the intensities of carbon C-5 signals, which was found to be specific, sensitive, repeatable and reproducible as discussed by the authors.

21 citations

Journal ArticleDOI
TL;DR: Results of coarse-grained molecular dynamics simulations indicate different organization of membrane lipids upon binding of arginine-based lipopeptides and the previously studied lysine- based ones.

21 citations

Journal ArticleDOI
TL;DR: Although the peptide studied is flexible in polar solvents, a tendency to adopt a helical structure was observed in the hydrophobic environment and it is rather difficult to select the position of the secondary element present in the structure of NPγ in solution.
Abstract: Neuropeptide γ is one of the largest members of the tachykinin family of peptides, exhibiting strong agonistic activity towards the NK-2 tachykinin receptor. This peptide was synthesized by the solid-phase method using the Fmoc chemistry. Circular-dichroism spectroscopy (CD) investigations of this peptide were performed in phosphate buffer, in the presence of sodium dodecylsulphate (SDS) micelles and trifluoroethanol (TFE) solutions and in DMSO-d6 using the 2D NMR technique in conjunction with two different theoretical approaches. The first assumes multiconformational equilibrium of the peptide studied characterized by the values of statistical weights of low-energy conformations. These calculations were performed using three different force fields ECEPP/3, AMBER4.1 and CHARMM (implemented in the X-PLOR program). The second method incorporates interproton distance and dihedral angle constraints into the starting conformation using the Simulated Annealing algorithm (X-PLOR program). The CD experiments revealed that although the peptide studied is flexible in polar solvents, a tendency to adopt a helical structure was observed in the hydrophobic environment. The NMR data (NOE effects) indicate a helical or reverse structure in the Ile7–His12 fragment of the peptide studied in DMSO-d6 solution. The results obtained cannot be interpreted in terms of a single conformation. Most of the conformations obtained with the ECEPP/3 force field possess a high content of a helical structure. None of the conformers, obtained with the AMBER4.1 and CHARMM force fields, can be considered as the dominant one. In all conformations several β-turns were detected and in some cases γ-turns were also found. But in fact, it is rather difficult to select the position of the secondary element(s) present in the structure of NPγ in solution. All conformers calculated with the X-PLOR program (with using NMR derived distance and torsion angle constraints) are stabilized by several β-turns. Common structural motives are a type IV β-turn in the Gln6–His12 fragment. All conformations obtained using two approaches adopt very similar turn shapes in the middle region of molecule and a random structure on the N- and C-terminal fragments. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd.

17 citations


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Journal ArticleDOI
TL;DR: A complete chemical and physicochemical characterization of chitin, chitosan and their derivatives is not possible without using spectroscopic techniques, so this review focuses on the application of Spectroscopic methods for the structural analysis of these compounds.
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.

848 citations

Journal ArticleDOI
TL;DR: In this review, various methods of chitosan extraction will be approached and compared; the importance of a new method of ecological extraction will been emphasized and several chemical modifications have been reported.

413 citations

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TL;DR: The results suggest that crosslinking electrospun hydroxyapatite-containing chitosan with genipin yields bio-composite scaffolds, which combine non-weight-bearing bone mechanical properties with a periosteum-like environment, which might be useful for the repair and regeneration of maxillofacial defects and injuries.

346 citations

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TL;DR: Chitosan is widely used in food and bioengineering industries for encapsulation of active food ingredients, enzyme immobilization, as a carrier for controlled drug delivery, in agriculture as a plant growth promoter and an antimicrobial agent.
Abstract: Shell fish processing industry is very common in coastal areas. While processing, only the meat is taken, the head and shells are discarded as waste. On an average, the sea food industry produces 80,000 tons of waste per year. The sheer amount of waste makes degradation a slow process causing accumulation of waste over a period of time. A very simple and effective solution to this environmental hazard is the recycling of shell waste to commercially viable products like chitin. Chitosan is the N-acetyl derivative of chitin obtained by N-deacetylation. Chitosan is widely used in food and bioengineering industries for encapsulation of active food ingredients, enzyme immobilization, as a carrier for controlled drug delivery, in agriculture as a plant growth promoter. Chitosan is also a defense elicitor and an antimicrobial agent. Chitosan has interesting properties such as biodegradability, biocompatibility, bioactivity, nontoxicity and polycationic nature. This review presents structural characteristics and physicochemical properties of chitosan. The methods of preparation of chitosan nanoparticles are detailed. Applications of chitosan nanoparticles are discussed. Applications include drug delivery, encapsulation, antimicrobial agent, plant growth-promoting agent and plant protector.

337 citations

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TL;DR: The adsorption capacity of nanofiber was unaltered after five recycling runs, which indicated the reusability of chitosan/PVA/zeolite nanofibrous membrane, which can be a useful material for water treatment at moderate concentration of heavy metals.

315 citations