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Romany A, Payne GF, Shen J. Effect of Acetylation on the Nanofibril Formation of Chitosan from All-Atom De Novo Self-Assembly Simulations. Molecules 2024; 29:561. [PMID: 38338306 PMCID: PMC10856132 DOI: 10.3390/molecules29030561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/08/2024] [Accepted: 01/15/2024] [Indexed: 02/12/2024] Open
Abstract
Chitosan-based materials have broad applications, from biotechnology to pharmaceutics. Recent experiments showed that the degree and pattern of acetylation along the chitosan chain modulate its biological and physicochemical properties; however, the molecular mechanism remains unknown. Here, we report, to the best of our knowledge, the first de novo all-atom molecular dynamics (MD) simulations to investigate chitosan's self-assembly process at different degrees and patterns of acetylation. Simulations revealed that 10 mer chitosan chains with 50% acetylation in either block or alternating patterns associate to form ordered nanofibrils comprised of mainly antiparallel chains in agreement with the fiber diffraction data of deacetylated chitosan. Surprisingly, regardless of the acetylation pattern, the same intermolecular hydrogen bonds mediate fibril sheet formation while water-mediated interactions stabilize sheet-sheet stacking. Moreover, acetylated units are involved in forming strong intermolecular hydrogen bonds (NH-O6 and O6H-O7), which offers an explanation for the experimental observation that increased acetylation lowers chitosan's solubility. Taken together, the present study provides atomic-level understanding the role of acetylation plays in modulating chitosan's physiochemical properties, contributing to the rational design of chitosan-based materials with the ability to tune by its degree and pattern of acetylation. Additionally, we disseminate the improved molecular mechanics parameters that can be applied in MD studies to further understand chitosan-based materials.
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Affiliation(s)
- Aarion Romany
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA;
| | - Gregory F. Payne
- Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, USA;
| | - Jana Shen
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA;
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Comas-Serra F, Estrada P, Minjares-Fuentes R, Femenia A. Evaluation of Acemannan in Different Commercial Beverages Containing Aloe Vera ( Aloe barbadensis Miller) Gel. Gels 2023; 9:552. [PMID: 37504431 PMCID: PMC10379354 DOI: 10.3390/gels9070552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/22/2023] [Accepted: 07/04/2023] [Indexed: 07/29/2023] Open
Abstract
Aloe vera (Aloe barbadensis Miller) gel is a frequently used ingredient in many food pro-ducts, particularly beverages, due to its reported health benefits. Studies have identified acemannan, a polysaccharide rich in mannose units which are partially or fully acetylated, as the primary bioactive compound in Aloe vera gel. The acemannan content and its degree of acetylation (DA) were measured in 15 different commercial beverages containing Aloe vera at varying concentrations (from 30% to 99.8%) as listed on the label. Other biopolymers such as pectins, hemicelluloses, and cellulose were also evaluated. Flavoured beverages (seven samples labelled as containing from 30% to 77% Aloe vera) presented low levels of acemannan (<30 mg/100 g of fresh sample) and were fully deacetylated in most cases. These samples had high levels of other polymers such as pectins, hemicelluloses, and cellulose, likely due to the addition of fruit juices for flavour. Unflavoured beverages (eight samples, with Aloe vera concentrations above 99% according to their labels) had variable levels of acemannan, with only three containing more than 160 mg/100 g of fresh sample. In fact, four samples had less than 35 mg acemannan/100 g of fresh sample. DA levels in all but one sample were lower than 35%, possibly due to processing techniques such as pasteurization causing degradation and deacetylation of the acemannan polymer. Legislation regarding Aloe vera products is limited, and manufacturers are not required to disclose the presence or quality of bioactive compounds in their products, leaving consumers uncertain about the true properties of the products they purchase.
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Affiliation(s)
- Francesca Comas-Serra
- Department of Chemistry, University of the Balearic Islands, Ctra. Valldemossa km 7.5, C.P. 07122 Palma de Mallorca, Spain
| | - Paula Estrada
- Department of Chemistry, University of the Balearic Islands, Ctra. Valldemossa km 7.5, C.P. 07122 Palma de Mallorca, Spain
| | - Rafael Minjares-Fuentes
- Department of Chemistry, University of the Balearic Islands, Ctra. Valldemossa km 7.5, C.P. 07122 Palma de Mallorca, Spain
- Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango, Av. Artículo 123 s/n, Fracc. Filadelfia, Gómez Palacio 35010, Durango, Mexico
| | - Antoni Femenia
- Department of Chemistry, University of the Balearic Islands, Ctra. Valldemossa km 7.5, C.P. 07122 Palma de Mallorca, Spain
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Hao W, Li K, Ge X, Yang H, Xu C, Liu S, Yu H, Li P, Xing R. The Effect of N-Acetylation on the Anti-Inflammatory Activity of Chitooligosaccharides and Its Potential for Relieving Endotoxemia. Int J Mol Sci 2022; 23:ijms23158205. [PMID: 35897781 PMCID: PMC9330575 DOI: 10.3390/ijms23158205] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/18/2022] [Accepted: 07/22/2022] [Indexed: 02/05/2023] Open
Abstract
Endotoxemia is mainly caused by a massive burst of inflammatory cytokines as a result of lipopolysaccharide (LPS) invasion. Chitooligosaccharides (COS) is expected to be a potential drug for relieving endotoxemia due to its anti-inflammatory properties. However, the structural parameters of COS are often ambiguous, and the effect of degree of acetylation (DA) of COS on its anti-inflammatory remains unknown. In this study, four COSs with different DAs (0%, 12%, 50% and 85%) and the same oligomers distribution were successfully obtained. Their structures were confirmed by 1H NMR and MS analysis. Then, the effect of DA on the anti-inflammatory activity and relieving endotoxemia potential of COS was researched. The results revealed that COS with a DA of 12% had better anti-inflammatory activity than COSs with other DAs, mainly in inhibiting LPS-induced inflammatory cytokines burst, down-regulating its mRNA expression and reducing phosphorylation of IκBα. Furthermore, this COS showed an obviously protective effect on endotoxemia mice, such as inhibiting the increase in inflammatory cytokines and transaminases, alleviating the injury of liver and intestinal tissue. This study explored the effect of DA on the anti-inflammatory activity of COS for the first time and lays the foundation for the development of COS as an anti-inflammatory drug against endotoxemia.
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Affiliation(s)
- Wentong Hao
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kecheng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
- Correspondence: (K.L.); (R.X.); Tel.: +86-0532-82898512 (K.L.); +86-0532-82898780 (R.X.)
| | - Xiangyun Ge
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao 266109, China
| | - Haoyue Yang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Chaojie Xu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Song Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Huahua Yu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Pengcheng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
| | - Ronge Xing
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; (W.H.); (X.G.); (H.Y.); (C.X.); (S.L.); (H.Y.); (P.L.)
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 1 Wenhai Road, Qingdao 266237, China
- Correspondence: (K.L.); (R.X.); Tel.: +86-0532-82898512 (K.L.); +86-0532-82898780 (R.X.)
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Sánchez LF, Cánepa J, Kim S, Nakamatsu J. A Simple Approach to Produce Tailor-Made Chitosans with Specific Degrees of Acetylation and Molecular Weights. Polymers (Basel) 2021; 13:polym13152415. [PMID: 34372018 PMCID: PMC8347713 DOI: 10.3390/polym13152415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/15/2021] [Accepted: 07/15/2021] [Indexed: 11/16/2022] Open
Abstract
Chitin is a structural polysaccharide that is found in crustaceans, insects, fungi and some yeasts. Chitin deacetylation produces chitosan, a well-studied biopolymer with reported chemical and biological properties for diverse potential applications for drug delivery, metal ion absorption, scaffolds and tissue engineering. Most known properties of chitosan have been determined from samples obtained from a variety of sources and in different conditions, this is, from chitosans with a wide range of degrees of N-acetylation (DA) and molecular weight (MW). However, as for any copolymer, the physicochemical and mechanical characteristics of chitosan highly depend on their monomer composition (DA) and chain size (MW). This work presents a simple methodology to produce chitosans with specific and predictive DA and MW. Reaction with acetic anhydride proved to be an efficient method to control the acetylation of chitosan, DAs between 10.6% and 50.6% were reproducibly obtained. In addition to this, MWs of chitosan chains were reduced in a controlled manner in two ways, by ultrasound and by acidic hydrolysis at different temperatures, samples with MWs between 130 kDa and 1300 kDa were obtained. DAs were determined by 1H-NMR and MWs by gel permeation chromatography.
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Affiliation(s)
- Luis-Felipe Sánchez
- Science Department, Pontificia Universidad Catolica del Peru—PUCP, Av. Universitaria 1801, Lima 32, Peru; (L.-F.S.); (J.C.)
| | - Jimmy Cánepa
- Science Department, Pontificia Universidad Catolica del Peru—PUCP, Av. Universitaria 1801, Lima 32, Peru; (L.-F.S.); (J.C.)
| | - Suyeon Kim
- Engineering Department, Pontificia Universidad Catolica del Peru—PUCP, Av. Universitaria 1801, Lima 32, Peru;
| | - Javier Nakamatsu
- Science Department, Pontificia Universidad Catolica del Peru—PUCP, Av. Universitaria 1801, Lima 32, Peru; (L.-F.S.); (J.C.)
- Correspondence:
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Son YJ, Hwang IK, Nho CW, Kim SM, Kim SH. Determination of Carbohydrate Composition in Mealworm ( Tenebrio molitor L.) Larvae and Characterization of Mealworm Chitin and Chitosan. Foods 2021; 10:640. [PMID: 33803569 PMCID: PMC8002850 DOI: 10.3390/foods10030640] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/14/2021] [Accepted: 03/15/2021] [Indexed: 11/16/2022] Open
Abstract
Mealworm (Tenebrio molitor L.) is a classic edible insect with high nutritional value for substituting meats from vertebrates. While interest in mealworms has increased, the determination of carbohydrate constituents of mealworms has been overlooked. Thus, the aim of the present study was to investigate the carbohydrate content and composition of mealworms. In addition, the characteristics of mealworm chitin were determined as these were the major components of mealworm carbohydrate. The crude carbohydrate content of mealworms was 11.5%, but the total soluble sugar content was only 30% of the total carbohydrate content, and fructose was identified as the most abundant free sugar in mealworms. Chitin derivatives were the key components of mealworm carbohydrate with a yield of 4.7%. In the scanning electron microscopy images, a lamellar structure with α-chitin configuration was observed, and mealworm chitosan showed multiple pores on its surface. The overall physical characteristics of mealworm chitin and chitosan were similar to those of the commercial products derived from crustaceans. However, mealworm chitin showed a significantly softer texture than crustacean chitin with superior anti-inflammatory effects. Hence, mealworm chitin and chitosan could be employed as novel resources with unique advantages in industries.
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Affiliation(s)
- Yang-Ju Son
- Smart Farm Research Center, Korea Institute of Science and Technology, Gangneung Institute of Natural Products, Gangneung 25451, Korea; (Y.-J.S.); (C.W.N.); (S.M.K.)
- Department of Food and Nutrition and Research Institute of Human Ecology, Seoul National University, Seoul 08826, Korea;
| | - In-Kyeong Hwang
- Department of Food and Nutrition and Research Institute of Human Ecology, Seoul National University, Seoul 08826, Korea;
| | - Chu Won Nho
- Smart Farm Research Center, Korea Institute of Science and Technology, Gangneung Institute of Natural Products, Gangneung 25451, Korea; (Y.-J.S.); (C.W.N.); (S.M.K.)
| | - Sang Min Kim
- Smart Farm Research Center, Korea Institute of Science and Technology, Gangneung Institute of Natural Products, Gangneung 25451, Korea; (Y.-J.S.); (C.W.N.); (S.M.K.)
| | - Soo Hee Kim
- Department of Culinary Arts, Kyungmin University, Uijeongbu 11618, Korea
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He C, Ke M, Zhong Z, Ye Q, He L, Chen Y, Zhou J. Effect of the Degree of Acetylation of Chitin Nonwoven Fabrics for Promoting Wound Healing. ACS Appl Bio Mater 2021; 4:1833-1842. [PMID: 35014529 DOI: 10.1021/acsabm.0c01536] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Chitin and chitosan have been extensively used as wound dressings because of their special functions to promote wound healing. However, there was little focus on the effects of the degree of acetylation (DA) on wound healing. In this work, the regenerated chitin nonwoven fabrics with DA values of 90, 71, 60, and 42% were prepared, and the morphology and physical performances of the fabrics were characterized. Moreover, the effects of DA of the chitin nonwoven fabrics on wound recovery were studied with a full-thickness skin defect model in rats. In vitro experiments indicated that the chitin nonwoven fabrics exhibited good biocompatibility and blood compatibility and a low blood-clotting index (BCI). In vivo experiments revealed that the chitin nonwoven fabrics could accelerate wound healing more effectively than gauze by promoting re-epithelialization and collagen deposition as well as by stimulating neovascularization. The results of the wound healing process showed that DA of the chitin nonwoven fabrics had a profound effect on promoting wound healing. Notably, the regenerated chitin nonwoven fabrics with 71% DA significantly improved the wound healing compared to the commercial wound dressing Algoplaque film. Therefore, the regenerated chitin nonwoven fabrics are promising candidates for wound healing.
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Affiliation(s)
- Chen He
- Department of Chemistry, Hubei Engineering Center of Natural Polymers-based Medical Materials, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Meifang Ke
- Department of Biomedical Engineering, Hubei Province Key Laboratory of Allergy and Immune Related Diseases, School of Basic Medical Science, Wuhan University, Wuhan 430071, China
| | - Zibiao Zhong
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Qifa Ye
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, Hubei Key Laboratory of Medical Technology on Transplantation, Wuhan 430071, China
| | - Liu He
- Department of Biomedical Engineering, Hubei Province Key Laboratory of Allergy and Immune Related Diseases, School of Basic Medical Science, Wuhan University, Wuhan 430071, China
| | - Yun Chen
- Department of Biomedical Engineering, Hubei Province Key Laboratory of Allergy and Immune Related Diseases, School of Basic Medical Science, Wuhan University, Wuhan 430071, China
| | - Jinping Zhou
- Department of Chemistry, Hubei Engineering Center of Natural Polymers-based Medical Materials, Key Laboratory of Biomedical Polymers of Ministry of Education, Wuhan University, Wuhan 430072, China
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Hembach L, Bonin M, Gorzelanny C, Moerschbacher BM. Unique subsite specificity and potential natural function of a chitosan deacetylase from the human pathogen Cryptococcus neoformans. Proc Natl Acad Sci U S A 2020; 117:3551-3559. [PMID: 32015121 PMCID: PMC7035615 DOI: 10.1073/pnas.1915798117] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen that infects ∼280,000 people every year, causing >180,000 deaths. The human immune system recognizes chitin as one of the major cell-wall components of invading fungi, but C. neoformans can circumvent this immunosurveillance mechanism by instead exposing chitosan, the partly or fully deacetylated form of chitin. The natural production of chitosans involves the sequential action of chitin synthases (CHSs) and chitin deacetylases (CDAs). C. neoformans expresses four putative CDAs, three of which have been confirmed as functional enzymes that act on chitin in the cell wall. The fourth (CnCda4/Fpd1) is a secreted enzyme with exceptional specificity for d-glucosamine at its -1 subsite, thus preferring chitosan over chitin as a substrate. We used site-specific mutagenesis to reduce the subsite specificity of CnCda4 by converting an atypical isoleucine residue in a flexible loop region to the bulkier or charged residues tyrosine, histidine, and glutamic acid. We also investigated the effect of CnCda4 deacetylation products on human peripheral blood-derived macrophages, leading to a model explaining the function of CnCda4 during infection. We propose that CnCda4 is used for the further deacetylation of chitosans already exposed on the C. neoformans cell wall (originally produced by CnChs3 and CnCda1 to 3) or released from the cell wall as elicitors by human chitinases, thus making the fungus less susceptible to host immunosurveillance. The absence of CnCda4 during infection could therefore promote the faster recognition and elimination of this pathogen.
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Affiliation(s)
- Lea Hembach
- Institute for Biology and Biotechnology of Plants, University of Münster, 48143 Münster, Germany
| | - Martin Bonin
- Institute for Biology and Biotechnology of Plants, University of Münster, 48143 Münster, Germany
| | - Christian Gorzelanny
- Experimental Dermatology, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Bruno M Moerschbacher
- Institute for Biology and Biotechnology of Plants, University of Münster, 48143 Münster, Germany;
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Bellich B, D'Agostino I, Semeraro S, Gamini A, Cesàro A. "The Good, the Bad and the Ugly" of Chitosans. Mar Drugs 2016; 14:E99. [PMID: 27196916 PMCID: PMC4882573 DOI: 10.3390/md14050099] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/04/2016] [Accepted: 05/09/2016] [Indexed: 12/15/2022] Open
Abstract
The objective of this paper is to emphasize the fact that while consistent interest has been paid to the industrial use of chitosan, minor attention has been devoted to spread the knowledge of a good characterization of its physico-chemical properties. Therefore, the paper attempts to critically comment on the conflicting experimental results, highlighting the facts, the myths and the controversies. The goal is to indicate how to take advantage of chitosan versatility, to learn how to manage its variability and show how to properly tackle some unexpected undesirable features. In the sections of the paper various issues that relate chitosan properties to some basic features and to advanced solutions and applications are presented. The introduction outlines some historical pioneering works, where the chemistry of chitosan was originally explored. Thereafter, particular reference is made to analytical purity, characterization and chain modifications. The macromolecular characterization is mostly related to molecular weight and to degree of acetylation, but also refers to the conformational and rheological properties and solution stability. Then, the antimicrobial activity of chitosan in relation with its solubility is reviewed. A section is dedicated to the formulation of chitosan biomaterials, from gel to nanobeads, exploring their innovative application as active carrier nanoparticles. Finally, the toxicity issue of chitosan as a polymer and as a constructed nanomaterial is briefly commented in the conclusions.
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Affiliation(s)
- Barbara Bellich
- Laboratory of Physical and Macromolecular Chemistry, Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy.
| | - Ilenia D'Agostino
- Department of Life Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. ilenia.d'
| | - Sabrina Semeraro
- Department of Life Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy.
| | - Amelia Gamini
- Laboratory of Physical and Macromolecular Chemistry, Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy.
| | - Attilio Cesàro
- Laboratory of Physical and Macromolecular Chemistry, Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy.
- Elettra-Sincrotrone Trieste, Strada Statale 14 km 163.5, Area Science Park, 34149 Trieste, Italy.
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