Handbook of Natural Colorants, 2nd Edition

Handbook of Natural Colorants Second Edition A detailed survey of a variety of natural colorants and their different applications including textiles, polymers, and cosmetics Colorants describe a wide range of materials such as dyes, pigments, inks, paint, or chemicals, which are used in small quantities but play an important role in many products such as textiles, polymers, food, and cosmetics. As the effects of climate change begin to be felt, there has been a shift in focus in the field to renewable resources and sustainability, and an interest in the replacement of oil-based products with greener substitutions. As the push to adopt natural resources grows, there have been significant developments in the research and application of natural colorants as a step in the transition to a bio-based economy. The second edition of Handbook of Natural Colorants provides a detailed introduction to natural colorants in a marriage of theory and practice, from seed of plant to consumer demand. Presenting a wide range of viewpoints, the book briefly discusses the history of coloration technology and the current position of natural colorants before highlighting detailed information on regional plant source availability, colorant production and properties, as well as analytical methods for isolation, identification, and toxicity aspects. It also presents key applications in technical use and consumer products, including the use of natural colorants in textiles, hair dyeing, printing, and packaging. Finally, the text considers environmental and economic aspects of natural colorants. Handbook of Natural Colorants is a useful reference for dyers, textile producers, and researchers in the evolving field of sustainable chemistry, environmental sciences, agricultural sciences, and polymer sciences. Revised and updated content throughout to reflect developments in research and applications over the past decade New content on biotechnology in natural colorant production, natural colorants for mass coloration polymers, natural colorants in printing/packaging, and plant-based pigments Discusses strategies for scale-up, including consideration of energy, waste, and effluents For more information on the Wiley Series in Renewable Resources, visit www.wiley.com/go/rrs Cover Title Page Copyright Page Contents List of Contributors Series Preface Preface Part I Historical Development Chapter 1 History of Natural Dyes in the Ancient Mediterranean Civilization 1.1 Introduction 1.1.1 Ancient Mediterranean World 1.1.2 Dyes from Antiquity 1.1.3 Unveiling the Secrets of Ancient Dyes with Modern Science 1.2 Ancient Reds 1.2.1 Anthraquinone Reds 1.2.2 Redwoods 1.2.3 Flavylium/Anthocyanin Reds 1.2.3.1 Equilibria in solution 1.3 Ancient Blues 1.3.1 Indigo Blues 1.3.2 Anthocyanin Blues 1.4 Ancient Purples 1.4.1 Tyrian Purple: Real Purple from Sea Snails 1.4.2 Orchil Purples 1.4.3 Folium 1.5 Ancient Yellows 1.5.1 Flavonoid Yellows 1.5.2 Carotenoid Yellows 1.5.3 Chalcone and Aurone Yellows Acknowledgements References Chapter 2 Colors in Civilizations of the World and Natural Colorants: History under Tension 2.1 Introduction 2.2 The Triumph of Mauveine: Synthetic Fulfillment of the Antique Purplemania 2.3 Blue: From Kingly Regional to Globally Democratic 2.4 Red and Yellow: From Micro to Macro Scales 2.5 What Is the Future for Natural Colorants in the Dawning Era of Renewable Resources? Acknowledgement References Chapter 3 History of Natural Dyes in North Africa_Egypt 3.1 Introduction 3.2 Natural Dyes in Pharaonic Textiles 3.3 Dyeing Techniques 3.4 Dye Sources 3.4.1 Woad 3.4.2 Indigo 3.4.3 Red 3.4.4 Yellow 3.4.5 Black 3.4.6 Brown 3.4.7 Green 3.4.8 Purple 3.5 Dyeing in Coptic Textiles 3.6 Wool-Dyed Fabric with Natural Dye 3.7 Dyes in Islamic Textiles 3.8 Mordants References Part II Natural Colorants in Different Regions of the World Chapter 4 Sources for Natural Colorants in Europe 4.1 Introduction 4.2 Cultivation 4.2.1 Potential European Dye Plants Yesterday and Now 4.2.2 Modern Cultivation Methods—General Facts 4.2.3 Blue-Dye Plants 4.2.4 Red-Dye Plants 4.2.5 Yellow-Dye Plants 4.2.6 Brown-Dye Plants 4.2.7 Production of Dye Extracts 4.3 Natural Colorants from Agro-Food Residues 4.4 Natural Colorants from Forestry and Timber Industry 4.5 Relevant Examples for the Application 4.6 Conclusions, Discussion, and Summary Acknowledgement References Chapter 5 Dyes in South America 5.1 Introduction 5.2 Annatto 5.3 Turmeric 5.4 Marigold 5.5 Cochineal and Carmine Acknowledgements References Chapter 6 Natural Dyes in Eastern Asia (Vietnam and Neighboring Countries) 6.1 Introduction 6.2 Annatto (Bixa orellana L., Family Bixaceae) 6.3 Tea (Camellia sinensis (L.) Kuntze, Family Theaceae) 6.4 Umbrella Tree (Terminalia catappa L., Family Combretaceae) 6.5 Mackloeur (Diospyros mollis L. Griff, Family Ebenaceae) 6.6 Indigo (Indigofera L., Family Fabaceae) 6.6.1 Indigofera tinctoria L. 6.6.2 Indigofera galegoides DC 6.6.3 Strobilanthes cusia (Baphicacanthus) 6.7 Henna (Kok Khan or Khao Youak in Laos) (Lawsonia spinosa L., Family Lythraceae) 6.8 Nacre (African Mahogany, Khaya senegalensis, Family Meliaceae) 6.9 Sappan Wood (Caesalpinia sappan L., Family Fabaceae) 6.10 Japanese Pagoda Tree Flowers (Sophora japonica L., Family Leguminosae) 6.11 Turmeric (Curcuma longa L., Family Zingiberaceae) 6.12 Sapodilla (Manilkara zapota L. or Achras zapota, Family Sapotaceae) 6.13 Betel (Piper betel L., Family Piperaceae) 6.14 Eucalyptus (Eucalyptus, Family Myrtaceae) 6.15 Caesalpinia Yellow (Caesalpinia pulcherrima L., Family Fabaceae) 6.16 Brow-Tuber; Yam (Dioscorea cirrhosa Lour, Family Dioscoreaceae) 6.17 Others Acknowledgement References Chapter 7 Sources for Natural Colorants in China 7.1 Introduction 7.2 Sophora japonica Yellow 7.3 Turmeric 7.4 Gardenia Yellow 7.5 Emodin 7.6 Baicalin 7.7 Berberine 7.8 Henna 7.9 Monascus Red 7.10 Madder 7.11 Sorghum Red 7.12 Mulberry Red 7.13 Shikonin 7.14 Indigo 7.15 Condensed Tannins 7.16 Tea Polyphenols 7.17 Gallnut References Chapter 8 Sources, Application, and Analysis of Natural Colorants: An Indian Perspective 8.1 Introduction 8.2 Natural Dyes in India 8.2.1 History 8.2.2 Traditional Processes of Dyeing with Natural Dyes in Different Parts of India 8.2.3 Sources of Natural Dyes in India 8.2.4 Use of Some Natural Dyes in Traditional Textiles of India 8.3 Details of Some Dye Sources and Their Application in India 8.3.1 Turmeric 8.3.2 Pomegranate 8.3.3 Flame of Forest 8.3.4 Marigold 8.3.5 Safflower 8.3.6 Annatto 8.3.7 Madder 8.3.8 Indian Mulberry 8.3.9 Arjuna 8.3.10 Sappanwood 8.3.11 Eucalyptus 8.3.12 Catechu 8.3.13 Gallnut 8.3.14 Myrobolan 8.3.15 Lac 8.3.16 Indigo References Chapter 9 Natural Dye Gardens in North America 9.1 Introduction 9.2 Participants 9.3 Education 9.4 Motivation to Work with Natural Dye 9.5 Plant List—Cultivated Plants 9.6 Chemical Background of Most Relevant Plants 9.7 Plant List—Foraged Plants 9.8 Plants with Indigotin 9.9 Importance of the Fibershed Movement 9.10 Educational and Community Gardens 9.11 Mexico 9.12 Canada 9.13 Future Research References Notes Part III Colorant Production and Properties Chapter 10 Chlorophylls 10.1 Introduction 10.2 Chemical Structures and Physicochemical Properties 10.3 Chlorophylls as Colorants 10.4 New Trends in the Use of Chlorophylls as Colorants 10.5 Stability and Analysis 10.6 Toxicological and Safety Aspects References Chapter 11 Indigo—Production and Properties 11.1 Introduction 11.2 Agronomy 11.2.1 Isatis 11.2.1.1 Developmental Stages and Climate and Soil Crop Requirements 11.2.1.2 Rotation 11.2.1.3 Soil Tillage and Seed Sowing 11.2.1.4 Weeds, Pests, and Diseases 11.2.1.5 Fertilizers and Irrigation 11.2.1.6 Harvesting and Yields 11.2.1.7 Seed Production 11.2.1.8 Isatis indigotica Compared with Isatis tinctoria 11.2.2 Persicaria 11.2.2.1 Introduction 11.2.2.2 Developmental Stages 11.2.2.3 Sowing, Harvesting, and Yield 11.2.2.4 Weeds, Pests, and Diseases 11.2.2.5 Fertilizer and Irrigation Requirement 11.2.2.6 Seed Production 11.2.3 Indigofera 11.3 Methods of Determining Indigo 11.4 Precursors in the Plants 11.5 Direct Dyeing with Indican 11.6 Indigo Formation 11.7 Extraction Procedures 11.7.1 Traditional Process Using Crushed Leaf Material 11.7.1.1 Isatis 11.7.1.2 Persicaria 11.7.2 Steeping in Water 11.7.2.1 Indigofera 11.7.2.2 Isatis 11.7.2.3 Persicaria 11.8 Purity of Natural Indigo 11.8.1 Purification by Sublimation 11.8.2 Impurities in Natural Indigo Acknowledgements References Chapter 12 Anthocyanins: Revisiting Nature’s Glamorous Palette 12.1 Chemical Basis 12.1.1 Chemical Structures 12.1.2 Equilibria in Solution 12.1.3 Kinetics 12.1.4 Color and Color Stability 12.1.5 Anthocyanins as Antioxidants 12.2 Natural Sources and Applications for Anthocyanins 12.2.1 Plants Sources, Content, Influencing Parameters 12.2.2 Food Colorants 12.2.3 Other Uses 12.2.4 Examples of Commercial Products and Processing References APPENDIX 1 A1.1 Multi-Equilibria in Acidic and Basic Media A1.2 Measuring the Equilibria Constants Chapter 13 Natural Colorants—Quinoid, Naphthoquinoid, and Anthraquinoid Dyes 13.1 Introduction 13.2 Benzoquinone Dyes 13.3 Diaryloylmethane Dyes 13.4 Naphthoquinone Dyes 13.4.1 Lawson (2-hydroxy-1,4-naphthoquinone, CI Natural Orange 6) 13.4.1.1 Properties and Use 13.4.1.2 Agricultural Aspects 13.4.2 Juglone (5-hydroxy-1,4-naphthoquinone, CI Natural Brown 7) 13.5 Anthraquinone Dyes 13.5.1 Main Components Emodin and Chrysophanol—Rheum and Rumex Species 13.5.2 Main Components Alizarin and/or Pseudopurpurin/Purpurin 13.5.2.1 Plant Sources 13.5.2.2 Madder CI Natural Red 8 References Chapter 14 Natural Colorants from Lichens and Mushrooms 14.1 Use of Lichen and Mushroom Colorants in History 14.2 Cultivation of Lichens and Mushrooms 14.3 Colorant Structures in Lichens and Mushrooms 14.3.1 Lichen Dyes: Orchils and Litmus 14.3.2 Yellowish, Brownish, and Reddish Colorants from Lichen 14.3.3 Blue Terphenylquinones from Mushrooms 14.3.4 Anthraquinones 14.3.4.1 Bloodred Webcap (Cortinarius sanguineus) 14.3.5 Other Colorants of Fungi 14.3.5.1 Yellows from Grevillines 14.3.5.2 Yellow and Orange Colors from Pulvinic Acid Derivatives 14.3.5.3 Brown from Badiones 14.4 Stability of Lichen and Mushroom Colorants 14.5 New Approaches to Lichen and Fungal Colorants References Chapter 15 Focus on Tannins 15.1 Introduction 15.2 Chemical Structure, Biosynthesis, and Degradation 15.3 Properties of Tannins 15.4 Chemical Activities of Tannins 15.5 Analysis of Tannins 15.5.1 Sample Preservation 15.5.2 Extraction and Purification 15.5.3 Quantification of Tannins 15.6 Use, Toxicology, and Safety Aspects of Tannins References Chapter 16 Carotenoid Dyes—Properties and Production 16.1 Introduction 16.1.1 Occurrence of Carotenoids 16.1.2 Chemistry of Carotenoids 16.1.3 Chemical Characteristics of Natural Carotenoids 16.2 Properties and Functions of Carotenoids 16.2.1 Carotenoids’ Role as Pro-vitamin A 16.2.2 Use of Carotenoids as Markers of Dietary Practices 16.2.3 Carotenoids as Antioxidants 16.2.4 Carotenoids in the Macular Region of the Retina 16.2.5 Carotenoids as Anticancer Agents 16.2.6 Carotenoids as Natural Colorants 16.3 General Procedure for Carotenoid Analysis 16.3.1 Sampling 16.3.2 Extraction 16.3.3 Saponification of Carotenoids 16.3.4 Chromatographic Separation 16.3.5 Chemical Tests 16.3.6 Detection and Identification of Carotenoids 16.3.7 Quantification of Carotenoids 16.4 Problems in Carotenoid Analysis 16.5 Factors Influencing Carotenoid Composition in Plant Sources 16.5.1 Stage of Maturity 16.5.2 Cultivar or Varietal Differences 16.5.3 Climatic or Geographic Effects 16.5.4 Post-Harvest Storage and Packing 16.5.5 Changes in Processing/Cooking 16.5.6 Effect of Agrochemicals References Chapter 17 Flavonoids as Natural Pigments 17.1 Introduction 17.2 Role of Localized Flavonoids in the Plant 17.3 General Flavonoid Chemical Structure 17.4 Biosynthesis of Flavonoids 17.5 Anthocyanins as Natural Colorants 17.5.1 Structure 17.5.2 Structural Transformation and pH 17.5.3 Temperature 17.5.4 Oxygen and Ascorbic Acid 17.5.5 Light 17.5.6 Enzymes and Sugars 17.5.7 Sulfur Dioxide 17.5.8 Co-Pigmentation and Metal Complexation 17.6 Other Flavonoids as Natural Colorants 17.6.1 Yellow Flavonoid Pigments 17.6.2 Tannins 17.6.3 Anthocyanin-Derived Pigments: Pyranoanthocyanins 17.7 Therapeutic Effects of Flavonoids in the Diet 17.8 The Use of Flavonoids as Food Colors in the US and EU References Chapter 18 Natural Colorants from Fungi 18.1 Introduction 18.2 Types of Fungi Colorants 18.3 Fungal Producer of Colorants 18.4 Bioprocess 18.4.1 Biosynthesis Pathway 18.4.2 Production and Extraction Process 18.5 Toxicity 18.6 Industrial Application of Fungi Colorants 18.7 Conclusion References Chapter 19 Natural Colorants from Cyanobacteria and Algae 19.1 Introduction 19.2 Phycobiliproteins from Cyanobacteria 19.2.1 Structural Characteristics of Phycobiliproteins 19.2.2 Food Grade Phycobiliproteins 19.2.3 Future Trends 19.3 Pigments from Microalgae 19.3.1 -Carotene from the Microalga Dunaliella, Salty but Effective! 19.3.1.1 β-Carotenefrom Microalgae 19.3.1.2 Dunaliella Species for Carotenoids 19.3.2 Why Carotenoids from Dunaliella? 19.3.2.1 Natural vs. Synthetic β-Carotene 19.3.2.2 Applications of β-Carotene 19.3.2.3 Advantages of Carotenoids Production from Dunaliella 19.3.2.4 Process for Production of β-Carotenefrom Dunaliella 19.3.2.5 Companies Producing Dunaliella 19.3.2.6 Marketed Products of β-Carotene 19.3.3 Haematococcus for Astaxanthin, the Red Gold Rush 19.3.3.1 Advantages of Astaxanthin over Other Carotenoids 19.3.3.2 Astaxanthin as Nutraceutical 19.3.3.3 Astaxanthin as Antioxidant 19.3.3.4 Astaxanthin for Health 19.3.3.5 Astaxanthin for Salmon and Trout Feeds 19.3.3.6 Astaxanthin for Humans 19.3.3.7 Production System for Haematococcus 19.3.3.8 Companies Producing Astaxanthin from Haematococcus 19.3.3.9 Astaxanthin-Containing Formulations 19.4 Natural Colorants from Macroalgae (e.g., Seaweeds) 19.4.1 Biodiversity of Seaweeds 19.4.2 Seasonal Variations and Environmental Threats 19.4.3 Major Classes of Seaweed Pigments 19.4.3.1 Chlorophylls 19.4.3.2 Carotenoids 19.4.3.3 Phycobiliproteins 19.5 Conclusion References Chapter 20 Biotechnological Production of Microbial Pigments: Recent Findings 20.1 Introduction 20.2 Microbial Pigments Market 20.3 Production Strategies 20.4 Novel Extraction Technologies for Pigments Recovery 20.5 Regulation and Biosynthesis of Microbial Pigments 20.6 Strain Engineering Strategies for Pigment Production 20.7 Trends in New Microbial Sources of Pigments 20.8 Microbial Pigments Applications 20.8.1 Solar Cells 20.8.2 Therapeutic Application 20.8.3 Other Applications 20.9 Regulations on Microbial Pigments Use 20.10 Conclusions and Future Perspectives References Chapter 21 Analytical Methods for Characterization and Standardization of Natural Dyes and Pigments 21.1 Introduction 21.2 Chemical Analysis—Identification 21.3 Quantification by Sum Parameters 21.4 Applicatory Tests 21.5 Product Performance References Chapter 22 Wood—From Natural Color Patterns Toward Naturally Altered Color Impressions 22.1 The Color of Wood 22.1.1 Wood Chemical Composition 22.1.2 Wood Anatomical Appearance 22.1.3 Physical Properties of the Wood Surface 22.2 Coatings 22.3 Dyes 22.3.1 Impregnation 22.3.1.1 Technology 22.3.1.2 Color 22.3.1.3 Products 22.4 Color Modification 22.4.1 Drying 22.4.1.1 Basics 22.4.1.2 Technology 22.4.1.3 Color 22.4.2 Steaming 22.4.2.1 Basics 22.4.2.2 Technology 22.4.2.3 Color 22.4.3 Thermal Treatment 22.4.3.1 Technology 22.4.3.2 Color 22.4.4 Ammoniation 22.4.4.1 Basics 22.4.4.2 Color 22.4.5 Bleaching 22.4.5.1 Basics 22.4.5.2 Color 22.4.6 Enzymatic Treatment 22.4.6.1 Basics 22.4.6.2 Laccases 22.4.7 Radiation 22.4.7.1 Basics 22.4.7.2 Color 22.4.7.3 Technology 22.5 Outlook References Chapter 23 The Role of Mordants in Fixation of Natural Dyes 23.1 Introduction 23.2 Metal Salts 23.3 Biomordants 23.4 Substrate Pretreatments 23.5 No Mordant References Chapter 24 Textile Coloration with Natural Dyes and Pigments 24.1 Introduction 24.2 Reasons for Natural Coloration 24.3 The Dyestuff–Fiber Interaction 24.4 Design of a Dyeing Process 24.5 Transfer of a Dyeing Process into Technical Scale 24.6 Processes and Resources 24.7 Technical Requirements for a Natural Dyestuff 24.7.1 Gamut and Color Shade 24.7.2 Fastness Criteria 24.8 Handling of Natural Dyes in a Technical Dyehouse 24.9 Mordanting 24.10 Natural Dyes on an Industrial Scale 24.10.1 Dyeing Technology—Exhaust Process 24.10.2 Hank Dyeing of Woolen Yarn and Production of Woolen Caps 24.10.3 Dyeing of Cones in a Yarn Dyeing Machine 24.10.4 Dyeing of Cotton Fabric on a Jet Dyeing Machine 24.10.5 Fabric Dyeing on a Garment Dyeing Machine 24.10.6 Dyeing of Polyamide Tights in a Paddle Dyeing Machine 24.10.7 Dyeing Technology—Continuous Dyeing 24.11 Conclusion Acknowledgement References Chapter 25 Hair Coloration with Natural Dyes and Pigments 25.1 Introduction 25.2 Human Hair 25.3 General Requirements on Hair Dyeing Concepts 25.4 Chemical Principles of Dyestuff Binding 25.5 Relevant Natural Dyes for Hair Dyeing 25.5.1 Naphthoquinone Dyes—Henna and Walnut 25.5.1.1 Henna, CI (Color Index) Natural Orange 6 25.5.1.2 Juglon, CI Natural Brown 7 25.5.2 Indigo 25.5.3 Metal Complexes 25.5.4 Metal Reaction Dyes 25.5.5 Anthraquinoid Dyes 25.6 Specialties 25.7 Regulations References Chapter 26 Natural Colorants in the Mass Coloration of Plastics 26.1 Introduction 26.2 Representative Examples Acknowledgement References Chapter 27 Natural Colorants in Printing/Packaging 27.1 Introduction 27.2 Packaging Films 27.3 Film Coloration 27.4 Paper Dyeing 27.5 Paints Acknowledgement References Chapter 28 Technical Aspects and Requirements to Produce Natural Colorants—Processes and Product Standardization 28.1 Introduction 28.2 Sources of Plant Material—Product I 28.2.1 Organic Farming 28.2.2 Sustainable Farming 28.2.3 Native Species 28.2.4 Farming for Food or/and Natural Colorants 28.2.5 Residual Materials and By-Products 28.3 Processing to Dyestuff—Product II 28.4 Quality Control and Standardization of a Dye (Product II) 28.4.1 Anthocyanins 28.4.2 Flavonoids 28.4.3 Dye Lakes 28.5 Challenges for the Industrial Use of Natural Colorants 28.6 Dealing with Sustainability 28.7 Conclusions References Chapter 29 Environmental and Economic Position of Natural Colorants—Energy and Resources Balances, Sustainability, Ecology, and Costs 29.1 Introduction 29.2 Dye Plant Production 29.3 Dye Extraction and Dyestuff Production 29.4 Transportation 29.5 Textile Dyeing 29.6 Commercial Aspects—Costs 29.6.1 Basic Requirements for the Industrial Use of Natural Colorants 29.6.1.1 Precondition 1: acceptable costs of natural colorants and dyeing processes 29.6.1.2 Precondition 2: feasible cost of process engineering 29.6.1.3 Precondition 3: compliance with requested colorfastness properties 29.6.1.4 Precondition 4: competitive cost of naturally dyed products 29.6.1.5 Precondition 5: security of natural colorant supply 29.6.2 Consumer Expectations 29.6.3 Market Research for Naturally Dyed Products 29.7 Production Costs of Natural Colorant Products 29.7.1 Cost Categories 29.7.2 Aspects Influencing Production Costs 29.8 Prices of Synthetic Dyes—How Much Are Textile Companies Prepared to Pay for Dyes? 29.9 Acceptable Production Costs through a Mixed Portfolio (Agricultural Primary Production and Residues from Other Production Processes) 29.10 Closed-Loop Economy: Toward a Zero-Emission and Zero-Waste Society 29.11 Considerations Concerning the Life Cycle 29.12 Conclusion: Aspects Influencing Market Development for Natural Colorants References Chapter 30 Aspects of Human Toxicology and Consumer Safety 30.1 Introduction 30.2 Basic Aspects of Xenobiotic-Induced Toxicity 30.3 Toxicological Aspects of Natural Colorants in Food and Medical Applications 30.3.1 Risk Assessment 30.3.2 Therapeutic Effects (= Risk) 30.4 Toxicological Aspects of Natural Colorants in Cosmetics 30.4.1 Risk Assessment 30.5 Toxicological Aspects of Natural Colorants in Textile Dyeing 30.5.1 Plant Extracts 30.5.2 Pretreatment Agents and Mordants 30.5.3 Wastewater and Antimicrobial Compounds 30.5.4 Dyed Products 30.6 Test Methods for Toxicity Screening 30.6.1 Extract Preparation 30.6.2 Cytotoxicity 30.6.3 Mutagenicity and Carcinogenicity 30.6.4 Antimicrobial Activity 30.6.5 Metabolism and in vivo Animal Bioassays Acknowledgement References Index EULA "Colorants can be dyes, pigments, inks, paint, or chemicals. Colorants are used in relatively small quantities but play an important role in many products including textiles, polymers, food and cosmetics. The growing interest and focus on renewable resources, sustainability and replacement of oil-based products are driving forces to adopt natural resources, and there have been significant developments in the research and application of natural colorants as part of the transition to a bio-based economy"-- Provided by publisher