Plant based natural dyes and mordnats: A Review

TL;DR: A brief review of natural colourant from plant sources, their classification, chemical constituents responsible for producing different colours, its activities and effect of different mordants on the hue is discussed.

Abstract: Natural dyes, which were pushed during the last sixty years into the background by synthetic dyes, are recently again becoming object of consumer interests. This is due to the awareness of possible risks during production of synthetic dyes which involve use of petrochemical based raw materials and the violent chemical reactions for their synthesis. The manufacture of such dyes is energy intensive with adverse impact on environment adding to its pollution. Many of these dyes, especially the azo- based ones, are found to be carcinogenic. In this background, a brief review of natural colourant from plant sources, their classification, chemical constituents responsible for producing different colours, its activities and effect of different mordants on the hue is discussed. Different classes of mordants employed for fixation of natural colouration on textiles substrated, its mechanism and plant sources are also discussed.

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J. Nat. Prod. Plant Resour., 2012, 2 (6):649-664
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ISSN : 2231 – 3184
CODEN (USA): JNPPB7
649
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Plant based natural dyes and mordnats: A Review
K. H. Prabhu* and Aniket S Bhute
Department of Textile Chemical and Colour, Wool Research Association, Kolshet Road, Thane -
400 607, Maharashtra. INDIA.
_____________________________________________________________________________________________
ABSTRACT
Natural dyes, which were pushed during the last sixty years into the background by synthetic dyes, are recently
again becoming object of consumer interests. This is due to the awareness of possible risks during production of
synthetic dyes which involve use of petrochemical based raw materials and the violent chemical reactions for their
synthesis. The manufacture of such dyes is energy intensive with adverse impact on environment adding to its
pollution. Many of these dyes, especially the azo- based ones, are found to be carcinogenic. In this background, a
brief review of natural colourant from plant sources, their classification, chemical constituents responsible for
producing different colours, its activities and effect of different mordants on the hue is discussed. Different classes of
mordants employed for fixation of natural colouration on textiles substrated, its mechanism and plant sources are
also discussed.
Key words: Natural dyes, Natural mordants, Textiles, Sources
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INTRODUCTION
Natural colourants covers all the dyes and pigments derived from plants, insects and minerals, i.e. derived from
natural resources. The dyeing with natural colourants was one of the oldest techniques practiced by the ancient
civilization people. This is evident from the Ajanta, Ellora, Sithannavasal, Mithila wall paintings (mural art)[1] and
Egyptian pyramids which had been exclusively done with natural colourants. Moreover, at the Spanish caves of
Altamira and Elcatillo and French Pyrene caves of Niaux [2], mineral earths and other inorganic pigments like ferric
oxide for red, ferrous oxide for yellow and copper carbonate for blue have been used extensively in their mural
paintings. Vedas [3] also mentioned red, yellow, blue, black and white as main dyeing colours and expressed that,
the ancient craftsmen dyed blue form indigo, yellow from turmeric and saffron, brown from cutch and red from lac,
safflower and madder. Thus, natural dyes have been an integral part of human life since time immemorial.
The invention of the first synthetic dyes by William Henry Perkin in 1856 changed the situation and later, the
synthetic dyes received faster acceptability due to a wide range of applications in various fields like food [4],
cosmetic [5], photodynamic therapy [6], non-linear optical activity [7, 8, 9] and more importantly in textile
industries [10, 11] due to ease in dyeing, and overall cost factor. But, during the last few decades, the use of
synthetic dyes is gradually decreasing due to an increased environmental awareness and harmful effects because of
either toxicity or their non-biodegradable nature. In addition to above, some serious health hazards like allergic and,
carcinogenicity are associated with the synthetic dyes. As a result, recently a ban has been imposed all over the
world including European Economic Community (EEC), Germany, USA and India on the use of some synthetic
dyes. The advantages of using natural colourants are manifolds as they are eco-friendly, safe for body contact,
unsophisticated and harmonised with nature [12], obtained from renewable sources and also their preparation
involves a minimum possibility of chemical reactions. The shades produced by natural dyes/colourants are usually
soft, lustrous and soothing to the human eye. Generally natural dyes do not cause health hazards; on the contrary,

K. H. Prabhu et al
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they sometimes act as a health-
care substance. Furthermore, the use of natural dyes offers no disposal problems.
However, the natural dyes have their own limitations like availability, colour yield, stability, and complexity of
dyeing process and reproducti
on of shades. Furthermore, natural dyes cannot entirely replace synthetic dyes, but
they have their own place in the market.
India is richly endowed with vast variety of natural flora. It is estimated that, in India there are some 500 varieties of
plants that can yield natural colours
many villages by expert’s craftsmen in the country. Natural dyes, when used by them have many limitations of
fastness and brilliancy of shade
. However, when used along with metallic mordants they produce bright and fast
colours. The use of metallic mordants is not always eco
producing colours one can use natural mordants a eco
mind, a
n attempt has been made in this paper here to give scientific overview on natural colourants and
from plants
, their classification, list of sources and
Classifications of Natural Dyes
Natural Colourants are classified in various ways broadly depending on chemical functional groups (Structure) and
their Hue which are discussed below.
Based on Structure
Most commonly available natural colourants fa
anthraquinones, alpha napthoqinones, flavones, dihydropyrans, an
Indigoid dyes
This class is the oldest dye known to the world since about 400 years. The Egypt
wrapped in cloths dyed with Indigo. Earlier, Indigo was used as a black dye till its property to dye blue was
discovered. The main colouring principle is a glucoside of
tinctoria
(native to Asia) and several other species like, dyer’s woad
Polygonum tinctorium [17]
, Eupatorium leave
there are about 54 species
of Indigofera available of which 10
commercialised. The Indigo and Indigoids are vat dyes applicable to both cellulose and protein fibres. Besides this,
Indigo is used in medicine [20]
as anticancer agent,
Anthraquinone dyes
Quinonoids are fused benzenoid ring systems (three rings in case of anthraquinone and two rings in case of
naphthaquinones) posses enough conjugation to achieve colour. Almost all the red natural dyes are based on the
anthraquinoid structure having both pl
textiles since 2000 B.C.), Alizarin
(Fig. 3) and Purpurin (Fig. 4)
(dyes cotton Turkey red with alu
insect dye cochineal or carminic acid
mordanted wool and silk. Kermes or kermisic acid
tassar and wool with reddish tones
[22]
Fig. 2:
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care substance. Furthermore, the use of natural dyes offers no disposal problems.
However, the natural dyes have their own limitations like availability, colour yield, stability, and complexity of
on of shades. Furthermore, natural dyes cannot entirely replace synthetic dyes, but
they have their own place in the market.
India is richly endowed with vast variety of natural flora. It is estimated that, in India there are some 500 varieties of
[13, 14]
. The art and craft of producing natural dyed textile is being practiced in
many villages by expert’s craftsmen in the country. Natural dyes, when used by them have many limitations of
. However, when used along with metallic mordants they produce bright and fast
colours. The use of metallic mordants is not always eco
-
friendly. Therefore, instead of using violent technology for
producing colours one can use natural mordants a eco
-friendl
y way to achieve almost similar results. Keeping this
n attempt has been made in this paper here to give scientific overview on natural colourants and
, their classification, list of sources and
its application for textile colouration.
Natural Colourants are classified in various ways broadly depending on chemical functional groups (Structure) and
their Hue which are discussed below.
Most commonly available natural colourants fa
lling under this system of classification includes indigoids,
anthraquinones, alpha napthoqinones, flavones, dihydropyrans, an
thocyanidin and carotenoids
This class is the oldest dye known to the world since about 400 years. The Egypt
ian mummies burried in tombs were
wrapped in cloths dyed with Indigo. Earlier, Indigo was used as a black dye till its property to dye blue was
discovered. The main colouring principle is a glucoside of
Indican (Fig.1)
, occurs in the leaves of
(native to Asia) and several other species like, dyer’s woad
Isatis tinctoria
[16]
, Eupatorium leave
[18], Wrightia tinctoria and
Mercurialis leiocarpa
of Indigofera available of which 10
–
12 species yield dye and only 4 of them have been
commercialised. The Indigo and Indigoids are vat dyes applicable to both cellulose and protein fibres. Besides this,
as anticancer agent,
astringent, anti-
inflammatory and antiulcerous.
Fig. 1: Indican
Quinonoids are fused benzenoid ring systems (three rings in case of anthraquinone and two rings in case of
naphthaquinones) posses enough conjugation to achieve colour. Almost all the red natural dyes are based on the
anthraquinoid structure having both pl
ant and mineral origin. Rubia tinctorium and
R. cordifolia
(Fig. 2)
(is the first natural dye produced synthetically in 1869)
(dyes cotton Turkey red with alu
m), Emodin (Fig. 5)
from Persian berries and the
insect dye cochineal or carminic acid
(Fig. 7) from Coccus cacti
(produce brilliant scarlet on tin and alum
mordanted wool and silk. Kermes or kermisic acid
(Fig. 7) from female insect
Coccus ilicis
[22]
. These are generally mordant dyes.
Fig. 2:
Alizarin Fig. 3: Munjistin
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650
care substance. Furthermore, the use of natural dyes offers no disposal problems.
However, the natural dyes have their own limitations like availability, colour yield, stability, and complexity of
on of shades. Furthermore, natural dyes cannot entirely replace synthetic dyes, but
India is richly endowed with vast variety of natural flora. It is estimated that, in India there are some 500 varieties of
. The art and craft of producing natural dyed textile is being practiced in
many villages by expert’s craftsmen in the country. Natural dyes, when used by them have many limitations of
. However, when used along with metallic mordants they produce bright and fast
friendly. Therefore, instead of using violent technology for
y way to achieve almost similar results. Keeping this
n attempt has been made in this paper here to give scientific overview on natural colourants and
mordants
Natural Colourants are classified in various ways broadly depending on chemical functional groups (Structure) and
lling under this system of classification includes indigoids,
thocyanidin and carotenoids
[15].
ian mummies burried in tombs were
wrapped in cloths dyed with Indigo. Earlier, Indigo was used as a black dye till its property to dye blue was
, occurs in the leaves of
Indigofera
[16]
(indigenous to Europe),
Mercurialis leiocarpa
[19]. In India,
12 species yield dye and only 4 of them have been
commercialised. The Indigo and Indigoids are vat dyes applicable to both cellulose and protein fibres. Besides this,
inflammatory and antiulcerous.
Quinonoids are fused benzenoid ring systems (three rings in case of anthraquinone and two rings in case of
naphthaquinones) posses enough conjugation to achieve colour. Almost all the red natural dyes are based on the
R. cordifolia
, used for dyeing
(is the first natural dye produced synthetically in 1869)
[21] Mungistin
from Persian berries and the
(produce brilliant scarlet on tin and alum
Coccus ilicis
is used to dye silk,

K. H. Prabhu et al
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Fig. 6:
Carminic acid
Alphanaphthoquinones
Typical example of this class is lawsone (henna)
is juglone (Fig. 9)
, obtained from
shades of orange.
Flavonoids
Flavonoids are aromatic oxygen containing heterocyclic pigments (i
in the epidermal cells of plant parts and are chemically known as 2
of the most widespread groups of natural constituents which are important to man not only because they contrib
to plant colour but also because of their physiological activities. They yield yellow dyes which can be classified
under flavones, isoflavones, aurones and chalcones. Most of the natural yellows are derivatives of hydroxyl and
methoxy substituted flavo
nes and isoflavones. Common example is weld (containing luteolin pigment
giving brilliant and fast colours on both wool and silk. Some of the other pigments are Fisetin, Isohamnetin,
Quercetin (Figs.11-13)
as shown below.
Fig. 10: Luteolin
Fig. 11: Fisetin
Di-hydropyrans
Closely related in chemical structure to the flavones are substituted di
form, haematoxylin. These are
important natural dyes for dark shades on silk, wool and cotton. Logwood, brazil
wood and sappan-
wood are the common example.
Anthocyanidins
Anthocyanins (in Greek, antho means flower, kyanos means blue) are glycosides of 2
(fl
avilium ionic form is stable out of all other possible forms), intensely coloured sap
responsible for different colours in higher plants. These are probably the best
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Fig. 4: Purpurin
Fig. 5: Emodin
Carminic acid
Fig. 7: Kermisic acid
Typical example of this class is lawsone (henna)
(Fig.8)
, cultivated mainly in India and Egypt. Another similar dye
, obtained from
the shells of unripe walnuts. These dyes are generally disperse dyes and give
Fig. 8: Juglone Fig. 9: Lawsone
Flavonoids are aromatic oxygen containing heterocyclic pigments (i
n latin ‘flavus’
means yellow) specially located
in the epidermal cells of plant parts and are chemically known as 2
-phenyl-1,4-
benzopyrone systems. These are one
of the most widespread groups of natural constituents which are important to man not only because they contrib
to plant colour but also because of their physiological activities. They yield yellow dyes which can be classified
under flavones, isoflavones, aurones and chalcones. Most of the natural yellows are derivatives of hydroxyl and
nes and isoflavones. Common example is weld (containing luteolin pigment
giving brilliant and fast colours on both wool and silk. Some of the other pigments are Fisetin, Isohamnetin,
as shown below.
Fig. 12:
Isohamnetin
Fig. 13:
Quercetin
Closely related in chemical structure to the flavones are substituted di
-
hydropyrans, viz. haematin and its leuco
important natural dyes for dark shades on silk, wool and cotton. Logwood, brazil
wood are the common example.
Anthocyanins (in Greek, antho means flower, kyanos means blue) are glycosides of 2
-
phenyl benzopyrillium salts
avilium ionic form is stable out of all other possible forms), intensely coloured sap
responsible for different colours in higher plants. These are probably the best
-
known natural food colourants since
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651
, cultivated mainly in India and Egypt. Another similar dye
the shells of unripe walnuts. These dyes are generally disperse dyes and give
means yellow) specially located
benzopyrone systems. These are one
of the most widespread groups of natural constituents which are important to man not only because they contrib
ute
to plant colour but also because of their physiological activities. They yield yellow dyes which can be classified
under flavones, isoflavones, aurones and chalcones. Most of the natural yellows are derivatives of hydroxyl and
nes and isoflavones. Common example is weld (containing luteolin pigment
(Fig. 10))
giving brilliant and fast colours on both wool and silk. Some of the other pigments are Fisetin, Isohamnetin,
Isohamnetin
Quercetin
hydropyrans, viz. haematin and its leuco
important natural dyes for dark shades on silk, wool and cotton. Logwood, brazil
phenyl benzopyrillium salts
avilium ionic form is stable out of all other possible forms), intensely coloured sap
-soluble plant pigments
known natural food colourants since

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they are widely distributed in plant kingdom and their colour range from red of apples, to blue of grapes, to purple of
brinjals. The large variation in the colours is attributed to the corresponding number of hydroxyl groups, the degree
of methoxylation, the nature and number of monosaccharides attached to the cation and their position of attachment,
the nature and number of carboxylic acids attached to the monosaccharides[23], the acylated derivatives of
monosaccharides and the pH of biological environment (e.g. cyanin is red under acidic conditions, violet at neutral
and blue under basic conditions). The naturally occurring member of this class includes carajurin as shown in Fig.
14, a direct orange dye for wool and cotton. It is obtained from the leaves of Bignonia chica.
Fig. 14: Carajurin
Carotenoids: Linearly conjugated polyene tetraterpenes are represented by carotenoids which are widely distributed
in plants and animals. The carotenoids are brightly coloured pigments in which the highly conjugated -electron
system confers different colours like yellow, orange and red to the molecule. The name carotene is derived from the
orange pigment found in carrots separated by Wackenroder (1831)[24]. There are two types of carotenoids present
in nature, carotene (e.g. β-carotene (Fig. 15) from Daucus carota) and xanthophylls (e.g. lutein (Fig. 16) from
Tagetes erecta)[25].
Fig.15: β-carotene
Fig.16: Lutein
Based on Hue
In the Colour Index, the dyes are classified according to chemical constitution as well as major application classes.
Within application class, the dyes are arranged according to hues. Natural dyes form a separate section. The no. of
dyes in each hue are given below. Some dyes produce more than one hue.
Table 1: Showing the number of dyes in each hue as per the colour index
C.I. NATURAL NO. OF DYES PERCENT
Yellow 28 30.4
Orange 6 6.5
Red 32 34.8
Blue 3 3.3
Green 5 5.5
Brown 12 13.0
Black 6 6.5
Of the 92 natural dyes listed in Colour Index, chemical structure of 67 dyes is disclosed. Many dyes have more than
one compound and some dyes have identical structures[26]. About more than 100 vegetable origin dyes, colouring
matter derived from root, leaf, bark, trunk or fruit of plants, list of the important sources are given in Table-2.
Extraction of plant natural colourants
Natural Dyes cannot be used directly from their renewable sources. Using raw materials for dyeing has many
limitations. Safe and cheap extraction of main colouring component is most important without affecting the
extraction conditions and avoiding any contamination in various extraction techniques. Several extraction
methodologies for natural dye that comply with both consumer preference and regulatory control and that are cost
effective are becoming more popular. Some of the techniques of extractions of natural dyes [76] are
• Simple Aqueous Methods
• Complicated Solvent Systems
• Supercritical Fluid Extraction
• Ultrasonic Extraction

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Table 2: List of natural dyes source and their applications [27-75]
Species
(Family Name)
Common name Part used
Colour
obtained
Colour Application
Acacia catechu
(Mimosaceae)
Cutch tree, Khair Heart wood Red
Textile (shipsails, mailbags), Calico
printing
Aegle marmelos
(Rutaceae)
Bael, Brel tree Fruit Yellow Food colourant
Alcea rosea
(Malvaceae)
Hollyhock Flower Red Food colourant
Alkanna tinctoria
(Boraginaceae)
Dyer’s alkanet Root Purple Pharmaceutical, Colourant
Allium cepa
(Liliaceae)
Onion, Piyaz Skin Orange Textile dyeing
Alnus sieboldiana
(Betulaceae)
Alnus Fruit Red Textile dyeing
Annona reticulate
(Annonaceae)
Ramaphal, Bullock heart Unripe fruit Black Textile dye
Anthemis tinctoria
(Asteraceae)
Dyer’s chamomile Flower Yellowish
Textile dyeing, hair dye and
stimulant
Ardisia humilis
(Myrsinaceae)
Aringudi Fruit Yellowish Textile dye
Artocarpus heterophyllus
(Moraeceae)
Kathal Stem, Root Yellow Textile dyeing (silk)
Baptisia australis
(Fabaceae)
Baptisia Flower Yellowish Textile dye
Berberis vulgaris
(Berberidaceae)
Kashmal Root, Bark Yellowish Food and textile colourant
Beta vulgaris
(Chenopodiaceae)
Red beet Root Red, Yellow Industrial food colourant
Bidens pilosa
(Asteraceae)
Lumb Leaf Yellow Textile dye
Caesalpinia sappan
(Fabaceae)
Sappan Wood Red Textile dyeing
Caesulia axillaris
(Asteraceae)
Balonda Plant Yellow Textile dye
Cassia auriculata
(Fabaceae)
Tarwar Flower Yellow Textile dye
Casuarina equisetifolia
(Casuarinaceae)
Janglisaru, Beef wood Bark Brown Textile dye
Cheiranthus cheiri
(Brassicaceae)
Wallflower Leaf, petal Yellow Textile dye
Chlorophora tinctoria
(Moraceae)
Fustic Wood Yellow Textile dye
Chloroxylon swietenia
(Rutaceae)
Satin wood, Bhirra Bark Yellow Textile dye
Coccus cacti
(Coccidae)
Carmine Dried insect body Red Textile dye
Coccus ilicis
(Coccidae)
Kermes Insect body Red Textile dye
Coreopsis tinctoria
(Asteraceae)
Coreopsis Flower Yellowish Textile dye
Coriaria nepalensis
(Coriariaceae)
Makola Wood Red Textile dye
Cotinus coggygria
(Anacardiaceae)
Young fustic Wood, leaf
Yellowish
orange
Textile dye
Curcuma longa
(Zingiberaceae)
Haldi, Turmeric Rhizome Yellow Food, cosmetic, textile colourant
Dahlia indica
(Asteraceae)
Dahlia Petals Peech gold Textile dye
Datisca cannabina
(Datiscaceae)
Akalbir, Hemp Root Yellow
Textile dyeing (wool, silk), in
calicoprinting
Delonix regia
(Fabaceae)
Gul Mohar Flower
Deep
crimson
Textile dyeing
Delphinium zalil
(Ranunculaceae)
Guljali, Larkspur Flower Yellow Textile dyeing and in Calicoprinting
Diospyros malabarica
(Ebenaceae)
Galab Unripe fruit Brown Textile dyeing and tanning
Embellia ribes
(Myrsinaceae)
False pepper, Barberang Fruit Red Textile dyeing
Fagopyrum esculentum
(Polygonaceae)
Buckwheet, Kota Grain Yellow Textile dye
Galium verum Lady’s Bedstraw Root Red Food and Textile dye