Chitin and Chitosans in the Bioeconomy

173 Pages·2022·12.518 MB·English

by  Serge Perez, Jean-Luc Wertz

Chitin and Chitosans
in the Bioeconomy

Chitin and Chitosans
in the Bioeconomy
Serge Perez and Jean-Luc Wertz
First edition published 2022
by CRC Press
6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487–2742
and by CRC Press
2 Park Square, Milton Park, Abingdon, Oxon, OX14 4RN
© 2022 Taylor & Francis Group, LLC
CRC Press is an imprint of Taylor & Francis Group, LLC
Reasonable efforts have been made to publish reliable data and information, but the authors and
publisher cannot assume responsibility for the validity of all materials or the consequences of
their use. The authors and publishers have attempted to trace the copyright holders of all material
reproduced in this publication and apologize to copyright holders if permission to publish in this
form has not been obtained. If any copyright material has not been acknowledged please write and
let us know so we may rectify in any future reprint.
Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced,
transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or
hereafter invented, including photocopying, microf lming, and recording, or in any information
storage or retrieval system, without written permission from the publishers.
For permission to photocopy or use material electronically from this work, access www.
copyright.com or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive,
Danvers, MA 01923, 978–750–8400. For works that are not available on CCC please contact
[email protected]
T rademark notice: Product or corporate names may be trademarks or registered trademarks and
are used only for identif cation and explanation without intent to infringe.
L ibrary of Congress Cataloging - in - Publication Data
A catalogue record for this book is available from the Library of Congress
ISBN: 978-1-032-12848-1 (hbk)
ISBN: 978-1-032-12861-0 (pbk)
ISBN: 978-1-003-22652-9 (ebk)
DOI: 10.1201/9781003226529
Typeset in Times
by Apex CoVantage, LLC
Contents
Foreword 1 ................................................................................................................ix
Foreword 2 ............................................................................................................. xiii
Biographies ............................................................................................................xxv
Acknowledgments ................................................................................................xxvii
Chapter 1 Introduction ..........................................................................................1
1.1 History and Key Features of Chitin and Chitosans ...................1
1.2 Bioeconomy ...............................................................................4
1.2.1 Def nition in the EU ......................................................4
1.2.2 Bioeconomy and European Green Deal. .......................4
1 .2.3 Bioeconomy and Circular Economy .............................5
1.2.4 Bioeconomy and Sustainability ....................................6
1.2.5 Life-Cycle Assessment (LCA) ......................................8
1.3 Chitin and Chitosan Market .......................................................9
1.4 Scientif c Societies for Chitin and Chitosans in
the World .................................................................................. 10
1.5 Bioref neries ............................................................................. 11
1.5.1 General Concept and First Bioref neries ..................... 11
1.5.2 Shell Bioref neries .......................................................12
1.6 Biobased Plastics ...................................................................... 13
1.7 Structure of the Book ...............................................................15
Chapter 2 Occurrence of Chitin ..........................................................................21
2.1 Sources throughout the Biosphere ........................................... 21
2.2 Exoskeleton of Arthropods ...................................................... 21
2.3 Cell Walls of Various Fungi and Algae ...................................25
2.3.1 Fungal Cell Walls ........................................................25
2.3.2 Algal Cell Walls ..........................................................27
Chapter 3 Extraction of Chitin and Preparation of Chitosans ............................ 31
3.1 Extraction of Chitin ................................................................. 31
3.1.1 Chemical Extraction ................................................... 31
3.1.1.1 Chemical Demineralization ........................ 31
3.1.1.2 Chemical Deproteinization .......................... 32
3.1.1.3 Decolorization .............................................34
3.1.1.4 Recent Developments ..................................34
3.1.2 Biological Extraction ...................................................34
3.1.2.1 Enzymatic Demineralization and
Deproteinization .......................................... 35
v
vi Contents
3.1.2.2 Fermentation ................................................ 35
3.1.2.2.1 Lactic Acid Fermentation ........... 35
3.1.2.2.2 N on-Lactic Acid Fermentation ..... 36
3.2 Chitosans Preparation ..............................................................36
3.2.1 Chemical Deacetylation ..............................................36
3.2.2 Enzymatic Deacetylation ............................................37
Chapter 4 Structure of Chitin and Chitosans ...................................................... 41
4.1 Crystallography of Chitin ........................................................ 41
4.1.1 α-Chitin ....................................................................... 41
4.1.2 β-Chitin ....................................................................... 43
4.2 Crystallography of Chitosans and Their Allomorphs ..............46
4.3 Comparison between the Crystal Structures of
Chitin/Chitosan and Cellulose .................................................49
Chapter 5 Biosynthesis of Chitin ........................................................................ 53
5.1 Introduction .............................................................................. 53
5.2 A Common Biosynthetic Pathway ........................................... 53
5.2.1 CHS-Encoding Genes in Fungi and Insects ...............54
5.2.2 CHS Structure and Mode of Action ............................ 55
5.2.3 General Organization of CHS Domains ..................... 55
5.2.4 Catalytic Mechanism of CHS .....................................56
5.2.5 Transcriptional Regulation of Genes
Involved in Chitin Synthesis .......................................59
5.2.6 Signaling Pathways Ensuring Cell Wall
and Cuticle Integrity ...................................................59
5.3 Chitosomes and Assembly into Microf brils ...........................59
Chapter 6 Biodegradation of Chitin and Chitosans ............................................63
6.1 Enzymes in Chitin and Chitosans Degradation .......................63
6.1.1 Lytic Polysaccharide Monooxygenases .......................63
6.1.2 Chitinases ....................................................................66
6.1.3 Chitosanases ................................................................ 71
6.1.4 β-N-Acetylhexosaminidases ....................................... 71
6.1.5 Carbohydrate Esterases ...............................................72
6.1.6 Exo-β-Glucosaminidases (GlcNase) ...........................73
6.2 Chitin Degradation in Insects and Fungi ................................. 75
6.2.1 Insects ......................................................................... 75
6.2.2 Fungi ........................................................................... 75
Chapter 7 Properties of Chitin, Chitosans, and Their Derivatives .....................79
7.1 Derivatives of Chitosans and Chitin ........................................79
Contents vii
7.1.1 Chitosans Derivatives ..................................................79
7.1.1.1 O- and N-Carboxymethyl Chitosans ...........79
7.1.1.1.1 Reductive Alkylation ...................80
7.1.1.1.2 Direct Alkylation ........................80
7.1.1.2 Click Chemistry ........................................... 81
7.1.1.3 Graft Copolymerization. .............................. 81
7.1.1.4 Chitosan-Grafted Cyclodextrin
Derivatives ...................................................83
7.1.1.5 Chitosans Modif cations Using Ionic
Liquids .........................................................84
7 .1.1.6 Complex Formation of Chitosans ................84
7.1.2 Chitin Derivatives .......................................................85
7.1.2.1 Chitin Nanocrystals .....................................85
7 .1.2.2 Derivatives by Grafting onto Chitin ............85
7.1.2.3 Carboxymethyl Chitin .................................85
7 .1.2.4 Other Chitin Derivatives .............................87
7.1.2.5 Depolymerization ........................................87
7 .2 Solubility and Analysis of Chitin and Chitosans .....................87
7 .2.1 Solubility of Chitin ......................................................87
7 .2.2 Solubility of Chitosans ................................................88
7 .2.2.1 Effect of Solution pH ...................................88
7 .2.2.2 Effect of Molecular Weight .........................89
7 .2.2.3 Effect of Ionic Strength and
Temperature .................................................89
7 .2.3 Analysis of Chitosans ..................................................89
7.2.3.1 Infrared Spectroscopy .................................90
7.2.3.2 Fingerprinting Methods ............................... 91
7.2.3.3 NMR ............................................................91
7 .3 MW and Rheology of Chitin and Chitosans ...........................92
7.3.1 Rheology .....................................................................92
7.3.2 Flow Measurements ....................................................92
7 .4 Chitin’s and Chitosans’ Biological Properties .........................93
7.4.1 Antimicrobial Activity ................................................93
7.4.2 Antioxidant Activity ....................................................93
7.4.3 Mucoadhesive Properties ............................................93
7 .4.4 Penetration Enhancement Properties ..........................94
7.4.5 Mechanism of Chitin-Induced Activation
of Plant Innate Immunity ............................................94
7.4.6 Elicitation and Improvement of Crop
Yields ..........................................................................94
Chapter 8 Chitin and Chitosans Market and Applications in
the Bioeconomy ..................................................................................99
8.1 Chitin and Chitosans Market ...................................................99
8.1.1 Global Chitin and Chitosans Market ..........................99
viii Contents
8.1.2 Global Chitin Market ..................................................99
8.1.3 Global Chitosans Market and Analysis by Region,
Source, and Applications ............................................99
8.2 Applications ........................................................................... 103
8.2.1 Food Applications ..................................................... 103
8.2.1.1 Antioxidant Applications ........................... 103
8.2.1.2 Food Preservatives ..................................... 104
8.2.1.3 Antimicrobial Packaging ........................... 105
8.2.2 Dietary Fiber ............................................................. 105
8.2.3 Pharmaceuticals ........................................................ 106
8.2.4 Biomedical Products ................................................. 106
8 .2.4.1 Processing and Main Applications ............106
8.2.4.2 Tissue Engineering ....................................107
8.2.4.3 Wound Healing .......................................... 108
8.2.4.4 Contact Lenses .......................................... 108
8.2.4.5 Materials Based on Ionic Liquids .............. 108
8.2.4.6 Nonviral Gene Therapy .............................109
8.2.4.7 Intranasal Vaccine Delivery ...................... 109
8.2.4.8 Chitosans in Viral Surface Adsorption ..... 109
8.2.5 Cosmetics and Dermatological Applications ............109
8.2.6 Textiles ...................................................................... 110
8.2.7 Agriculture ................................................................ 110
8.2.8 Paper .......................................................................... 111
8.2.9 Enzyme Immobilization. ........................................... 111
8.3 Conclusion .............................................................................. 111
Chapter 9 Perspectives of Chitin and Chitosans in the Bioeconomy ............... 115
9.1 Introduction ............................................................................ 115
9.2 Sustainability of Chitin and Chitosans .................................. 115
9.3 Shell Bioref neries .................................................................. 116
9.3.1 Fractionation of Crustacean Shell Biomass .............. 116
9.3.2 Chitin and Chitosans Conversion into
Chemicals .................................................................. 117
9.4 Chitin and Chitosans from Fungi and Insects ....................... 119
9.5 Thermoplastic Chitin and Chitosans ..................................... 120
9.6 Chitosans Blends ....................................................................120
9.7 Conclusion .............................................................................. 121
G lossary ................................................................................................................125
Index ......................................................................................................................139
Foreword 1
Chitin is a representative polysaccharide with many original properties, such as algi-
nates, starch, pectins, hyaluronan, or carrageenans. Chitin is of universal importance
in living organisms. In turn, its main derivative, chitosan, has seen an explosive
number of assumed industrial applications in the recent two decades. The research
in chitin and chitosan has also gained signif cant traction in multiple domains rang-
ing from biology to advanced biomaterials, with massive ongoing efforts focused on
expanding the frontier of understanding structure–function relations associated with
this large family of polysaccharides.
T he ideal pure structure of chitin is described as a linear homopolymer with a
N-acetyl substitution on C2 that differentiates it from cellulose and allows specif c
chemical modif cations. Even when chitin is an abundant polymer that occurs in large
amounts in many organisms (mainly arthropods and fungi, the subject of C hapter 2) ,
academic research started late in the 1970s, and the 1st International Conference on
Chitin and Chitosan was organized in 1978. Chitin is not thermoplastic, and it is dif-
f cult to process when compared with synthetic petroleum-based polymers. To com-
pete with their synthetic counterparts, a natural polymer must offer similar material
properties and performance and at least nearly the same market price, along with
additional original properties. This should be the case of chitin and chitosan, given
the development associated with the extensive research on these biopolymers.
A s addressed in C hapter 3, initially, chitin industrial sources consisted of waste
from isolated crustaceous processing plants. The research developed rapidly, partic-
ularly over the past two decades. However, many studies have been carried out only
at laboratory scale, and the scaling and validation of many applications in different
domains have remained slow due to the diff culty to achieve reproducible properties
of the chitin obtained. In fact, chitin is diff cult to isolate from the mineral (cal-
cium and other salts) and proteinaceous matrix in which it occurs, and the meth-
ods of choice to obtain pure chitin depend essentially on the biological source and
its semi-crystalline structure. To a large extent, the industrial production of chitin
relies on chemical processes and the use of large volumes of water. The degree of
purity of isolated chitin imposes its reactivity during chemical modif cation and its
solubility in “good solvents from a thermodynamic point of view”, which are rare.
Consequently, the characterization of chitin is nearly impossible in terms of molecu-
lar weight and viscosity determinations due to the presence of aggregates.
In many natural polysaccharides, such characterization diff culties exist but are
often ignored, thus leading to both wrong interpretations of the behavior of the stud-
ied polymers and non-reproducible values for parameters such as solubility, molecu-
lar weight, viscosity, and degree of acetylation. In this regard, chitin appears irregular
and is often utilized only for relatively low-cost and large-scale applications where
homogeneity is not critical. Even for these types of applications, enzymatic or chemi-
cal modif cations will give heterogeneous reactions and f nal products.
Chitin is reminiscent of cellulose in the solid-state and solubilization with no
thermoplastic character, as explained in Chapter 4 . But it has not been studied as
ix