Plant-Based Natural Products: Derivatives and Applications

By Shahid Ul Islam

Intense research has been started all around the world in the past few decades to exploit different agents from natural products as eco-friendly alternative to synthetic and toxic chemicals. Natural products and their derivatives have received increasing attention for their use in many everyday applications ranging from food, medicine, textiles, and healthcare.This new book presents significant research advances about the use of natural products, mainly plant colorants, bioactive compounds and other plant extracts in the textile coloration, food, bioremediation and environmental applications. There are total eight chapters contributed by leading researchers covering the topics such as potential resurgence of natural dyes in applied fields, natural colorants from indigoid plants, phytochemistry of dye yielding plants, irradiation as novel pretreatment methods, dyeing studies with henna plant, phytoremediation of arsenic, and synthesis of curcumin complexes for medicinal and other industrial uses.

• Language: English
• Publisher: Wiley
• Release date: Jul 18, 2017
• ISBN: 9781119423874

Book preview

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 1

Potential 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: [e-mail]

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