Plant-Based Natural Products E-Book
171,99 €
Mehr erfahren.
- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
The book deals with novel applications of plant derived natural agents and their derivatives in the food, textile dyeing, medicinal, and environmental areas. Plant based natural products and their derivatives have strong influence on our everyday lives. They are needed for many everyday applications ranging from food, medicine, agriculture, textiles, and healthcare. This new book presents significant research advances about the use of plant-based natural products, mainly dyes and pigments, bioactive compounds and other plant extracts in the textile coloration, food, medicine, bioremediation and environmental applications. The topics of the ten informative chapters in Plant-Based Natural Products include the following: potential resurgence of natural dyes in applied fields; natural colorants from indigoid rich plants; phytochemical and pharmacological aspects of Butea monosperma plant; irradiation as novel pretreatment methods to improve wash fastness properties of plant derived natural dyes; dyeing studies with colorants extracted from the Lawsonia inermis plant; effect of drumstick leaf powder incorporation on quality of khakhra; physico-chemical properties of pineapple pomace powder and its incorporation in buffalo meat products; synthesis of curcumin complexes for medicinal and other industrial uses and phyto-remediation of toxic arsenic from wastewaters.
Sie lesen das E-Book in den Legimi-Apps auf:
Seitenzahl: 347
Veröffentlichungsjahr: 2017
Ähnliche
Contents
Cover
Title page
Copyright page
Preface
Chapter 1: Potential Resurgence of Natural Dyes in Applied Fields
1.1 Introduction
1.2 History
1.3 Advantages of Natural Dyes
1.4 Classification
1.5 Methods of Extraction and Dyeing
1.6 Potential Application of Natural Dyes
1.7 Conclusion
Acknowledgment
References
Chapter 2: Natural Dyes from Indigoid-Rich Plants: An Overview
2.1 Introduction to Natural Dyes
2.2 Indigoid Dyes: An Overview
2.3 Indigo-Rich Plant Species: Practices and Discussion
2.4 Safety Aspects and Sustainability
2.5 Conclusion and Future Outlook
References
Chapter 3: Phytochemical and Pharmacological Aspects of
Butea monosperma
L.
3.1 Introduction
3.2 Phytochemical Aspects
3.3 Sterols
3.4 Imides
3.5 Terpenoids
3.6 Miscellaneous Compounds
3.7 Biological Activities
3.8 Conclusion
References
Chapter 4: Radiation Pretreatment: A Potential Novel Technology to Improve Fastness Properties of Plant-Derived Natural Dyes
4.1 Introduction
4.2 Chemistry of Fabrics
4.3 Mordants and their Classification
4.4 Radiation and Its Role in Dyeing
4.5 Applications of Mordants
4.6 Conclusion
Acknowledgments
References
Chapter 5: Natural Colorant from
Lawsonia inermis
Leaves: Reflectance Spectroscopy-Induced Optimal Conditions of Extraction and Dyeing
5.1 Introduction
5.2 Materials and Methods
5.3 Results and Discussion
5.4 Conclusion
Acknowledgement
References
Chapter 6: Plant Food By-products and their Application in Food Industry
6.1 Introduction
6.2 Plant Origin Food By-products
6.3 Effects on the Quality Parameters of Food Products Incorporated with Plant By-products
6.4 Conclusion
References
Chapter 7: Effect of Drumstick Leaves (
Moringa oleifera
) Incorporation on Quality of Khakhra
7.1 Introduction
7.2 Materials and Methods
7.3 Results and Discussions
7.4 Conclusion
Acknowledgments
References
Chapter 8: Curcumin and Its Derivatives – Isolation, Synthesis, and Applications
8.1 Introduction
8.2 Isolation
8.3 Metal Complexes as Derivatives of Curcumin
8.4 Applications of Curcumin and Its Derivatives
8.5 Conclusions and Future Perspective
Abbreviations
References
Chapter 9: Investigating the Functional Properties of Pineapple Pomace Powder and Its Incorporation in Buffalo Meat Products
9.1 Introduction
9.2 Materials and Methods
9.3 Results and Discussion
9.4 Conclusion
Acknowledgment
References
Chapter 10: Green Adsorbents from Plant Sources for the Removal of Arsenic: An Emerging Wastewater Treatment Technology
10.1 Introduction
10.2 Arsenic Toxicity
10.3 Detoxification and Remediation of Arsenic
10.4 Adsorption as an Emerging Technology
10.5 Mechanism Followed by Green Adsorbent
10.6 Water Constraints Effect on Green Adsorbent
10.7 Regeneration of Green Adsorbent
10.8 Advantages, Shortcomings, and Recent Advances
10.9 Conclusion and Future Prospects
Acknowledgment
References
Index
End User License Agreement
Guide
Cover
Copyright
Contents
Begin Reading
List of Tables
Chapter 2
Table 2.1
Various plant species enriched with natural dyes in India [1–12,15–20].
Chapter 3
Table 3.1
A comprehensive list of the chemical constituents isolated from
Butea monosperma
flowers, roots, stems, and seeds.
Chapter 4
Table 4.1
Important conventional mordants [51, 52].
Table 4.2
Newly discovered mordants [13, 53].
Chapter 5
Table 5.1
Optimization criteria for extraction.
Table 5.2
Optimization criteria for dyeing.
Table 5.3
CIELa*b* Color coordinates, K/S values and fastness properties of wool fibres dyed with 20% (o.w.f.)
L. inermis
at optimal conditions for extraction and dyeing.
Chapter 6
Table 6.1
By-products obtained from different cereals.
Table 6.2
Various fiber sources utilized for formulation of fiber-rich meat products.
Chapter 7
Table 7.1
Proximate composition of dried drumstick leaves.
Table 7.2
Total polyphenols, flavonoids, and antioxidant activity of drumstick leaves.
Table 7.3
Physical and textural properties shadow-dried drumstick leaf powder incorporated khakhras.
Table 7.4
Nutritional characteristics of khakhras incorporated with shadow-dried drumstick leaf powder.
Chapter 8
Table 8.1
Medicinal applications of curcumin metal complexes.
Chapter 9
Table 9.1
Proximate, physicochemical, and functional properties of pineapple pomace powder.
Table 9.2
Antibacterial activity of pineapple pomace powder.
Table 9.3
Sensory analysis of sausages and patties.
Table 9.4
Effect of pineapple pomace powder incorporation on different quality parameters of buffalo meat sausage and patties.
Chapter 10
Table 10.1
Selective sulfide minerals of arsenic.
Table 10.2
Concentration of arsenic in different water sources reported in previous research [57].
Table 10.3
Major arsenic metabolic intermediates reported in various reports [6, 7].
Pages
ii
iii
iv
xiii
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
Scrivener Publishing100 Cummings Center, Suite 541JBeverly, MA 01915-6106
Publishers at ScrivenerMartin Scrivener ([email protected])Phillip Carmical ([email protected])
Plant-Based Natural Products
Derivatives and Applications
Edited by
Shahid-ul-Islam
This edition first published 2017 by John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA and Scrivener Publishing LLC, 100 Cummings Center, Suite 541J, Beverly, MA 01915, USA © 2017 Scrivener Publishing LLC For more information about Scrivener publications please visit www.scrivenerpublishing.com.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions.
Wiley Global Headquarters 111 River Street, Hoboken, NJ 07030, USA
For details of our global editorial offices, customer services, and more information about Wiley products visit us at www.wiley.com.
Limit of Liability/Disclaimer of Warranty While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials, or promotional statements for this work. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read.
Library of Congress Cataloging-in-Publication Data
Names: Ul-Islam, Shahid, editor. Title: Plant-based natural products : derivatives and applications/edited by Shahid Ul-Islam. Description: Hoboken, NJ, USA : Wiley, 2017. | Includes bibliographical references and index.| Identifiers: LCCN 2017023337 (print) | LCCN 2017023655 (ebook) | ISBN 9781119423881 (pdf) | ISBN 9781119423874 (epub) | ISBN 9781119423836 (hardback) Subjects: LCSH: Plant biotechnology. | Plant products. | Natural products. | Botanical chemistry. | BISAC: SCIENCE / Chemistry / Organic. Classification: LCC TP248.27.P55 (ebook) | LCC TP248.27.P55 P524 2017 (print) | DDC 630–dc23 LC record available at https://lccn.loc.gov/2017023337
Preface
Plant based natural products and their derivatives have strong influence on our everyday lives. They are needed for many everyday applications ranging from food, medicine, agriculture, textiles, and healthcare. This new book presents significant research advances about the use of plant-based natural products, mainly dyes and pigments, bioactive compounds and other plant extracts in the textile coloration, food, medicine, bioremediation and environmental applications. The topics of the ten informative chapters in “Plant-Based Natural Products: Derivatives and Applications” include the following: potential resurgence of natural dyes in applied fields, natural colorants from indigoid rich plants, phytochemical and pharmacological aspects of Butea monosperma plant, irradiation as novel pretreatment methods to improve wash fastness properties of plant derived natural dyes, dyeing studies with colorants extracted from Lawsonia inermis plant, effect of drumstick leaf powder incorporation on quality of khakhra, physicochemical properties of pineapple pomace powder and its incorporation in buffalo meat products, synthesis of curcumin complexes for medicinal and other industrial uses, and phyto-remediation of toxic arsenic from wastewaters.
I am confident that the readers of “Plant-Based Natural Products: Derivatives and Applications” will gain much useful information pertaining to plant based natural products, their derivatives and applications. It is appropriate here to acknowledge the expert assistance of the entire editorial team, and in particular Martin Scrivener, who shepherded these chapters to completion. I would like to take this opportunity to sincerely thank each of the authors who contributed the ten chapters in this book for their time and priceless effort expended.
Shahid-ul-Islam Indian Institute of Technology Delhi (IITD), Hauz Khas, New Delhi, India May 2017
Chapter 1Potential Resurgence of Natural Dyes in Applied Fields
Shahid Adeel1*, Sana Rafi2, Mahwish Salman2, Fazal-Ur-Rehman2 and Shazia Abrar3
1Department of Chemistry, Government College University Faisalabad, Pakistan
2Department of Biochemistry, Government College University Faisalabad, Pakistan
3Department of Applied Chemistry, Government College University Faisalabad, Pakistan
*Corresponding author: [email protected]
Abstract
Over the past decades, the industries around the globe have been involved in providing sustainable products to its consumers. Their synthesis and application have a much importance owing to their benefits for ecosystem. Plant-derived natural dyes are the substances that are gaining much popularity in the fields of food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. Their extraction using novel methods adds more aesthetic value to be used in different fields. This chapter describes the potential efficacy of natural colorants in applied fields. Hopefully, this chapter would satisfy the needs of natural dye reader, researchers, and industrialists who are trying to acquire new sources, their stability, and sustainability in fields other than textiles.
Keywords: Natural dyes, types, extraction, advance technology, fields
1.1 Introduction
Natural dyes are those colorants that are obtained from natural renewable sources such as minerals, plants, animals, and micro-organisms. These are highly environmental friendly and pose no serious threat to human life as well as ecosystem. These different resources are granted with highly colored substances that can be applied and fixed on materials commonly known as substrate and act as dye for textiles. These dyes contain an aromatic ring which have an auxochrome, responsible for resonance, and become able to impart color. Natural dyes were used to dye and print the substrate since the prehistoric times but their application down fall in 1856 with the accident discovery of synthetic dye (mauveine) by W.H. Perkin. Then synthetic dyes become superior over natural one owing to their availability at economical price with bright color, good fastness properties, and their reproducibility [1]. However, studies motivated the revitalization of natural dyes due to the toxic wastes, carcinogenic effects, and skin allergies caused by synthetic dyes [2, 3]. It was confirmed by many researchers that synthetic dyes contain 118 of the azo and benzidine dyes and when are photolytically degraded, their waste products release toxic aromatic amines. Most of the synthetic colorant (about 10–35%) cannot be fixed on the fabric properly and their effluents when become part of ecosystem, disturb the eco-balance [4, 5]. These factors bring awareness and urge many countries especially EU, USA, Canada, Germany, India, Pakistan, and other countries to completely ban on their frequent usage in different applied fields such as textile, food, cosmetics, and flavor [6, 7]. Hence, resurgence of natural dye is being welcomed around the globe.
1.1.1 Types of Natural Dyes
Natural dyes are of two types, i.e.,
Substantive dyes
Adjective dyes
1. Substantive Dyes
These dyes have good fastness properties and need no additional chemical (mordant) to fix it on materials. Fastness properties may refer to the resistance of the loss of colorant from the substrate. In textile industry color fastness to light, rubbing fastness and washing fastness are considered as effective properties of dyed fabric, while mordant are those chemicals that create strong bonding between fibers and dye molecule e.g., tannic acid [8]. These dyes will not only create affinity between fabric and dye molecule but also give a wide spectrum of color [9, 10].
2. Adjective Dyes
These dyes have poor fastness properties and need mordant to increase fixation of dye on substrate as shown in Figure below. In natural dyeing process, both synthetic (chemical) and biomordant are used. In chemical mordants, salts of aluminum, potassium, copper, iron, tin, etc. and even rare-earth metals are used [11, 12]. Biomordants are those substances that can obtain from natural sources (i.e. plants, animals, etc.) such as myrobolan (Terminalia chebula), tannin, tannic acid, guava, and banana leaves ash. [13]. However, it was suggested by many researchers that biomordant is safer and effective to use than chemical mordant [14]. As biomordants are easily biodegradable and eco-frienldy, while metal mordants such as Cu, Sn, and Cr may pose serious health hazards during handling and dyeing processes [15–17].
Complex formation among dye (pelargonidin), fabric (silk), and mordant (Al)
1.2 History
Natural dyes have been used extensively since long periods. Excavation and written records shows the interest of ancient people toward natural dye. They used natural colorant from soil, plants, animal, insects, and minerals. Some of these historical examples are given below:
People of Stone Age used metal to color their body and hair during hunting to gain magic power.
Firstly, they protect themselves with severe weather using tanned skin and later they used textiles.
Ancient Egyptian cuneiform texts also confirm the usage of natural organic colorant in their cloth dyeing.
People of Phoenicians Ages used purple dye from murex shells and this dye was so costly that Asiatic rulers can only wear purple colors. And after 17th century when Turks conquered Byzantium, the use of purple went declines and kermes were the only choice to dye their clothes.
Until the discovery of America kermes was used as a source of red color however, later it was replaced with cochineal.
Similarly, saffron was a good source of golden color used by Arabian and Chinese people [18].
Indigo dye (blue dye source) has been used since 640–320 BC and was only used for painting by Roman and Greeks.
Egyptian people used alizarin from madder for dyeing purpose.
Fustic in past was used to dye wool fabric.
Cotton textile industry used such cheap natural dyes since medieval period.
1.3 Advantages of Natural Dyes
Natural dyes contain numerous beneficial characteristics that make it superior again over synthetic dyes. Some of these advantages are mentioned below:
Handling of natural dyes is safer and noncarcinogenic during its application and processes.
Natural dyes have better biodegradability and generally have higher compatibility with the environment.
These dyes are nontoxic, nonallergic to skin, and noncarcinogenic [19].
They are renewable and sustainable product [20].
These dyes have wide range of shades depends on the part of plant used and type of mordant applied [21].
Most of natural dyes adsorb the industrial toxic wastes that help to clean the environment from pollution [22].
These dyes are a big source of income for poor through viable harvesting and sales of these plants that also provide rich and different sources of dyestuff.
Natural dyes are bestowed with numerous beneficial properties such as insect repellent, deodorants, and flame retardant [23].
These dyes also exhibit UV protection [24] fluorescence [25, 26], and antimicrobial properties as well as antioxidant properties [27].
Such dyes generate more attractive and highly functional value added products [28].
Application of the waste materials as sources of natural dye can help in the preservation of the environment and also reduce the cost of natural dyeing [29].
Natural dyes have wide range of applications such as food, cosmetics, agriculture, textile, pH indicator, and DSSC (dye-sanitized solar cells).
1.4 Classification
Natural dyes are identified on the basis of their
Structure
Color
Application
Here, we will discuss the classification basis on structure.
1.4.1 Structure Base
1. Flavonoids
Flavonoid is the major structural class of the natural dye plant and has been further divided into seven classes such as flavones, flavanones (e.g., citrus fruit), flavonols, isoflavones (e.g., pulses), anthocyanins, anthocyanidins, and proanthocyanidins (e.g., black tea, green tea, apple, and blackberry). This is responsible for imparting yellow color to the substrate. Weld (Reseda luteola) and woadwaxen (Genista tinctoria) are also examples of flavonoids group.
2. Tannin
Tannin is considered to be the most important components that are essential for dyeing with natural dyes, especially to obtain brown shades of color. Babool (A.nilotica), pomegranate rind, and gallnut (Quercus infectoria) contain ellagic acid (tannin) [30]. Albizia coriaria plant species have shown the presence of tannin moieties in their molecular structure [31]. Due to the presence of polyphenolic group, this can be employed as safer biomordant.
3. Alkaloids
The main chemical constituent present in Adhatoda vasica is a bitter quinazoline alkaloid Vasicine and has high therapeutic value. It gives light yellow color with copper sulphate and gray with ferrous sulfate [32].
4. Indigoid
Indigoid being the source of blue color is an oldest natural colorant. In plant, it is in the form of water-soluble glucoside indicant and when exposed to air it is converted into indigotin (blue indigo), which is insoluble in water. Indigofera tinctoria being and Isatic tinctoira are the good example of natural Indigo dye that contains Indigoid structure and are cultivated in Asia and Europe. Other examples include Japanese knotweed (Polygonum tinctorium), common knotweed (P.aviculare), Nerium tinctorium, Marsdenia, and Lonchocarpus cyanescens.
Conversion of soluble indican to insoluble indigo
5. Quinone
Quinone dyes contain mono or polycyclic components in their structure. This class is further divided into three categories which are follows:
Benzoquinone
Benzoquinone is a dye component that has less pi-conjugation system and can be extracted from plant, mushroom, and lichens. e.g saffron (carthamin)
Anthraquinone
Anthraquinone dye is the largest group of quinone dye and forms stable complex with metal mordant. This group is present in plant bark and body of dry insects and responsible for red coloration. Examples of plants include Rhubarb and Rumex contain emodin, Chrysophanol, Aloeemodin, Rhein, and Physcion as major component and impart yellow to orange color on wool using different mordant.
Morinda augustifolia
contain Lucidin and Rubiadin as major colorant.
Napthaquinone
Most of the plants contain napthaquinone base dye and give orange, red, and reddish brown color, e.g., Alkanna tinctoria contain napthaquinone as major coloring component such as alkannin and Black carrot, which is confirmed by spectroscopic and chromatographic analysis [33]. Henna (Lawsone) and walnut (Juglone) also have napthaquinone dye.
6. Chlorophyll
Chlorophyll is considered to be the catalyst for photosynthesis in plant. It is also called metal dye complex owing to the presence of magnesium as central atom. Plants contain chlorophyll a and b, pheophytins, chlorophyllides, and pheophorbides, while algae contain chlorophyll a, b, c, d, and e as major coloring component. However, Green algae that has been utilized as a big source of dye and food colorant, possessed mixture of two compounds, chlorophyll a and b. Due to its physiochemical and photochemical properties, this substance has been applied as natural colorant, e.g., a green pigment can be obtained from Chlorella Spirogyra [34].
7. Carotenoid
Carotenoids are the important class of colorants that provide a wide range of shades. They are mostly fat soluble (polyene or lipochrome dyes), nitrogen free, and most of the brilliant red, orange, and yellow colors extracted from fruits, vegetables, flowers, fungi, birds, insects, crustaceans and trout, etc. contain carotenoid. It was first isolated by Wackenroder in 1831 from the carrot. Many sources revealed the presence of carotenoids, e.g., Capsanthin is present in green chili [6]. Similarly, Lycium ferocissimum contain β-carotene that gives yellow-reddish color on fabric [35]. Saffron and annatto are examples of polyene substantive dye and can be used to dye wool, silk, and cotton. Lycopene in Solanum lycopersicum (tomato), marigold and some species of bacteria also contain carotenoid structures.
1.5 Methods of Extraction and Dyeing
1.5.1 Conventional Method
Natural dyeing process is not as easy as it is considered. It needs a highly skillful art and complex method to extract and dyeing. Extraction is basically the rupture of cell wall of the plant to evolve the colorant in media. The conventional methods involve soaking, stirring, heating, reflux etc. [36]. Heat reflux is the most common method for the extraction of bioactive components from natural products. Supercritical fluids are appropriate for the extraction of compounds that can simply become degraded by light, oxygen, and high temperatures such as carotenoids [37]. Solvent extraction method has been always the primary option as far as industrial point of view is concerned owing to its simplicity and low costs. However, these methods are time and energy consuming, costly, and do not provide any bright color. So, there is a need of such methods that are sustainable, cost, and energy efficient with rapid treatment speeds. Such methods are called modern method which includes radiation treatments.
1.5.2 Modern Method
There is a growing demand for developing suitable extraction techniques for more efficient and effective extraction of available active component from the plant materials and their easily application on substrate that could not be easily achieved from conventional method. For this reason, various reports have been published on application of various modern techniques such as gamma radiation, UV radiation, ultrasonic radiation, microwave radiation, and plasma radiation. Microwave is the source of electromagnetic radiation comprising high frequency of 300–300,000 MHz and wavelength of 1–1000 mm. It transfers the heat to the whole material that ultimately increases the chemical reaction between fabric and dye molecule that is why it is known as volume heating. Microwave has recently been applied to extraction of plant materials [38]. Recently, it is found that chitosan-pretreated wool fabric has been dyed with green pigment (chlorophyll) obtained from algae (Chlorella Spirogyra) using microwave treatment [34]. They found that 4 min of radiation gave best K/S and excellent fastness properties. Ultrasonic radiation is the sound waves having frequency greater than audible to the human, i.e., 20 kHz–500 MHz. This energy in extraction causes cavitation, which is the formation and rupture of bubble that increases the kinetic and ultimately increases the chemical and physical reactions. Ultrasonic heating has been used for extraction of organic compounds from environmental matric and popular in food industry and also in textile industry [39]. Vankar et al. (2011) extracted colorant (morin) from Artocarpus Heterophyllus using sonicator and dyed cotton wool and silk [40]. Kamel et al. (2011) used ultrasonic bench top cleaner bath for dyeing cloth fabric using colorant from Cochineal dye [41]. They reported that the ultrasound approach improved dye ability as well as enhancement in the fastness properties of the dyed fabric. Rehman et al. (2013) concluded that the use of ultrasonic extraction method was found to have significant improvement in the percentage yield, color intensity, and redness color of crude dye extracted from Xylocarpus moluccensis compared to traditional boiling method [42]. Plasma is a dry and clean energy source used to minimize the wastewater caused by textile industry. It consists of electrons, neutrons, photons, free radicals metastable excited species, and negative and positive ions that can be used to modify the fabric surface through etching, cross-linking, and grafting and increase the adhesion properties of dye onto fabric. It also helps the fabric to resist against shrinkage and pilling. Many researcher use plasma technique in natural dyeing processes [43]. UV radiation having wavelength radiation from 200 to 400 nm and cannot be visualized by human eye. It has application in textile industry as to modify the surface of fabric without effects its physiochemical properties. UV removes the hydrophobic group with hydrophilic one that increases the dye penetration to the interior of the fabric [44]. Gamma radiation treatment to the fabric gave different result in the form of tear and tensile strength and pilling. Gamma radiation at low dosages effect the physical properties of fiber, as dosages increased the effects become more apparent and significant on strength of yarn, fabric strength, and abrasion resistance. Previous studies show that gamma ray treatment improves the extraction of color from natural material and deepens the color of dye without affecting the morphology of dye stuff. Gamma rays are also known for improvement in shrinking resistance, wrinkling resistance, and value addition in shades of dyed fabric at low temperature [45].
1.6 Potential Application of Natural Dyes
Dyes derived from natural sources can be used as eco-friendly colorants in different prominent fields owing to their aesthetic value, health benefits and other characteristics as an alternative substitute to potentially harmful synthetic dyes. Following are fields where natural dyes can be applied such as:
Food
Pharmaceutical
Dye Sensitized Solar Cells (DSSC)
Tanning
pH indicator
Agriculture
Textile
Cosmetics
Fragrance
Some of these are described in detail.
1.6.1 Food
Natural food colors have always a special place in the world tool owing to their health benefits [46]. However, for using natural additives of plant-based natural colors as food color, there must be three things keeping in mind, i.e., existence abundantly in nature, availability of raw material and nonchemical extraction material. Following plant-derived color of natural origin is used in food depending on their manufacturing, properties, stability, and extraction methodology [47]. These include anthocyanin, betalains, carminic acid, curcumin, riboflavins, and chlorophyll. Although some traditional sources of food colorants such as algae, insects, bacteria, fungi, and animals also exist but plant-based colorants have their own importance [48]. Hence, for liking a choice of food colorants, these have no disposal problem, soothing to eye, easily biodegradable, sensitive from origin of developments, addable in new products, stable, and act as health cure [49]. Below is the detail of plants colorants which are used as natural food colorants.
Anthocyanin belongs to flavonoid group. About 5000 flavonoids have been chemically found which are frequently used as food colorant [50]. Anthocyanins based on ring system are of two types formed by a three-carbon bonding system containing nine heterocyclic ring system. Depending on media, the color of anthocyanin is variable, e.g., in grapes, a natural reddish pigment. These are extracted from other plants such as red onion, red cabbage, and red berries and act as antioxidant and food additives [51].
Betalains are water-soluble class of colorants belongs to 10 families of Caryophyllales and fungi [52]. These are of two types depending on colors, i.e., red to reddish and yellowish orange. About more than 50 betacyanins, 131 betaxanthins have been identified. The most common food colorant as source of betalains is extracted from red beet [53].
Depending on its concentrate and method of extraction and media, its color is variable due which these are also used in drugs, cosmetics, and food products. As compared to anthocyanin betalains, they are more stable at room temperature. Other sources of betalain include cactus pear fruit and grain amaranth. There are excellent source of antioxidant, anti-inflammatory and anticancer and prevent cardiovascular diseases [54]. Carotenoids are also important food colorants having two C-20 units with eight isoprene units in structure. More than 750 naturally occurring carotenoids are founds and mostly are hydrophobic in nature [55]. Mostly carotenoids use in food industry are α-carotene, β-carotene, lycopene, and crocin [56]. These food colorants are used to prevent cancer, cystic fibroin, and arthritis, due to which these are used in vitamin supplements. These are also used as antioxidants, anticarcinogen, and in cellular regulating promoter [57]. Annatto is an example of yellow orange food colorants, used as colorant in beverage, bakery, and diary industries. It has also replaced nitrites (–NO2) is sausage, pepper products. Bixa orellana also contains carotenes colorant (bixin) having carboxylic acid group at the end, methyl ester on other side. It is also used as replacement of saffron.
Lycopene is another form of β-carotene that is orange red in color. Tomato lycopene is common carotenoids used as natural food colorant. It is powerful antioxidants that reduce the risks of prostate cancer [58].
Saffron the dried stigmas of Crocus sativus is also an example of carotenoid food colorant. It contains crocin which is bright yellow. It is approved by USA but EU does not consider it safe as food colorant. It is found in Gardenia jasminoides and Gardenia augusta where it is used in food colorant in many countries around the globe.
Curcumin Curcumin is the natural food colorant extracted from turmeric depending on medium extracted and applied its color is also variable. It is also part of traditional medicine owing to its therapeutic, antioxidant, and anti-inflammatory nature. It also cures many diseases such as Alzheimer disease and Parkinson disease. It is also a cheap and good source in food, cosmetics, and beverages as an alternative to saffron [59].
Some other natural food colorants include Marennine, Melanins, Riboflavin, Tetrapyrolles, and Chlorophyll [60]. All these have wonderful health and eco-friendly benefits. Melanin having dark black color is used in pasta, risotto, sauces, etc.
While riboflavin is a natural food colorant used in vitamin supplements. It is used in fruit drinks and milk.
Similarly greenish food colorants are attributed to chlorophyll and its derivatives, e.g., Chlorophyllin is a natural food colorant is safe for human health because it acts as deodorant in geriatric patients and as reductant for genotoxic effects. Conclusively, the food colorants being safe for ecosystem and human health are used to extend shelf life of food stuffs, cosmetics, pharmaceuticals, neutraceauticals, and attract consumer of ages. These are frequently available and act as alternative to artificial food colorants that are carcinogenic.
1.6.2 Pharmaceutical/Medicinal
As a consequence of an increasing demand for biodiversity, there is a need to obtain therapeutic drugs from natural products [61]. Natural dyes not only give aesthetic value to the matrix but also have blessed with numerous medicinal and therapeutic values. Three quarters of the world total population is relied on plant extract and their use for health care, and INDO- PAK has a variety of natural herbs having curative properties. The colorant present in natural sources have some phytochemical properties that enable them to use as drug or medicine. These colorants involve flavonoids, carotenoid, qunione, chlorophyll, etc. Chlorophyll a natural photosynthetic pigment also possess biological activities and can be applied as pharmaceutical substances having therapeutic value such as inflammatory activity, accelerant of wound healing, immune modulator properties, body deodorization in geriatric, and ileostomy patients and also helps to minimize the mutagenic activity. Many primary or secondary metabolites isolated from marine algae have been shown to possess bioactive efforts and so many drugs can be prepared from them [62]. The cytotoxic activities were also seen in Sargassaceae from Desmarestia ligulata and Dictyota dichotoma. Brown seaweeds have been used in traditional medicine. Sargassum graminifolium, is brown seaweed, commonly consumed as seafood and as medical resource for its antiallergic effects [63]. Flavonoid has been utilized in medical field owing to its anti-inflammatory, antiallergic, antitumor formation, antiviral, antidiabetic, cardiovascular protective, antioxidant, and antimicrobial. Alnus glutinosa (Alder) has antioxidant and antibacterial properties owing to the presence of genistic acid, sinapic acid, cichoric acid, cafteric acid, ferulic acid, etc.
Bixa orellana (Annatto) has been studied for its cytotoxity, antibacterial, antioxidant, antifungal, and analgesic activities containing compounds ishawarane, phytol, polyprenol, sterol, and sitosterol [64]. Similarly, Sappan heartwood contains triterpenoids, flavonoids, oxygen heterocyles, steroids, caesappanin A, and caesappanin B that are responsible for anticancer and antibacterial properties. Many other examples include Taxus baccata and Taxus brevifolia having taxol (Pactlitaxel), vinca alkaloids vinblastine and vincristine from Caranthus roseus content which are anticancer in nature.
1.6.3 Cosmetics
Natural dyes are originated from natural resources without any chemical treatment such as plants (e.g. Henna and saffron), insects (cochineal beetles), animals (some species of mollusks and shellfish), and mineral (ferrous sulfate and clay. There are almost hundreds of plants that have dye yielding characteristics along with medicinal properties [65, 66]. Until 1850, when synthetic dyes came into common use, natural dyes have been an excellent source of colors in cosmetic. Before the advent of synthetic products, women generally used natural colors and dyes from plants and herbs as hair color and as coloring agent of their home made cosmetics. Recently, due to eco-friendly behavior of natural colors and pigments, these have found their applications for coloring the green cosmetics [67, 68]. Moreover, natural dyes have the properties of UV-protection, antiaging, and healthfulness. Now a day, natural dyes have been increasingly used in cosmetic industry owing to their environment friendly nature, nontoxic properties, limited side effects, and more medicinal importance. Fortunately, there is a great increase in public awareness toward the use of natural dyes and colorants.
Different herbs and plants produce different intensity of colors depending on the amount used and have been used for coloring different cosmetic products as approved cosmetic colorant. Some natural coloring agents are as follows:
Turmeric: Rhizomes of the plant Curcuma longa Linn are used in cosmetics as yellowish coloring agent. It was first used as dye and later finds out its medicinal purposes. The principal coloring agent is known as curcumin. Along with coloring the cosmetic creams and lotion, turmeric has found extensive application in skin care products owing to their antifungal, antibacterial, and anti-inflammatory activities [69]. It has also been used in India–Pakistan in wedding masks. In natural personal care products, turmeric has been used as deep cleanser and brightener for oily skin [66].
Annatto is yellow-to-orange color that is derived from shrub Bixaorellana. The reddish orange color is due to the presence of carotenoid pigments in the resinous outer covering of the plant seeds. In cosmetics industry, Annatto is mainly used in personal care products as coloring agent of face products, lipsticks, permanent waves, shampoos, and skin care formulations. Annatto tree Bixa orellana is also called lipstick tree [70]. Saffron is generally known as crocus and derived from dried stigmas and upper parts of styles from plant Crocus sativus Linn
