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Research Trends in Molecular Biology, 2016: 85-98 ISBN: 978-81-308-0564-1
Editors: Nidhi Gupta and Koushik Biswas
4. Microbial pigment as a potential natural
colorant for contributing to mankind
1
Vivek Prakash Pankaj1 and Roshan Kumar2
Center for Energy and Environmental Engineering, NIT-Hamirpur (H.P)
2
Vellore Institute of Technology, University, Vellore, Tamil Nadu, India
Abstract. Colors are important for every organism as they are
inherent to all organisms. Living systems have natural colors in the
form of various pigments that helps in proper functioning of life
processes. Due to safety and benefits of natural colors over
synthetic colors there is a great demand in the market for the
natural pigments; especially microbial pigments as of widely used
synthetic pigments have harmful effects on the ecosystem and
living organisms. Industry workers and consumer have profound
dangers of the synthetic colors as they are in direct contact. Use of
microbial pigments have increased due to their numerous beneficial
properties like anticancer, ant proliferative, immune suppressive,
antibiotic, biodegradability etc. Various microorganisms, like
bacteria, fungi, yeast, mould and algae etc. are used for the
production of various pigments by using fermentation technology.
These microbial pigments have wide use and application, especially
in food industries, pharmaceutical
industries
and
textile
industries. Food grade pigments such as β-carotene, are pink
red, Riboflavin lycopene and monascus pigments are used in food
industry. In pharmaceutical industry pigments like Anthocyanin,
Correspondence/Reprint request: Dr. Roshan Kumar, Vellore Institute of Technology University, Vellore,
Tamil Nadu, India. E-mail: [email protected]
86
Vivek Prakash Pankaj & Roshan Kumar
Prodigiosin and Violacein are widely used to treat diseases. Several microbial
pigments are also used in textile industry. Advancement in technologies like
recombinant technology, fermentation technology, bioreactors etc. have made easy
extraction and production of microbial pigments.
Introduction
The most pleasurable feature of any article is its color. Various colors
are associated with variety of feelings such as red color shows warmth,
increases pulse rate and respiration, blue or green suggests cool and
peaceful environment and encourages relaxation [1]. Naturally colors are
obtained from color imparting compounds in living systems known as
pigments which play an important role in physiology and molecular
processes of microorganisms e.g. help to adapt at in extreme environment,
protection from solar radiation and photosynthesis. Since several decades,
taxonomists have been using pigments as a taxonomic tool for the
identification and classification of bacteria [2]. Pigments diversity depends
on the differences in their chemical structures and the presence of specific
chromophores [3].Since long time, we get pigments from natural sources,
and their use has increased due to the side effects caused by toxic nature of
the synthetic pigments. In this way the microbial pigments are a good
substitute. Synthetic colors are widely used in foodstuff, dyestuff, beauty
products and drugs making processes, comprise various lethal effects.
Many limitations of synthetic pigments are synthetic in nature,
carcinogenic hazardous. They are also non-environment friendly and nonbiodegradable [4]. Microbial pigments are a promising alternative
source for natural food grade pigments and have huge potential for
applications in foodstuff due to their natural color and safety to use; these
have medicinal properties, nutrients like vitamins. Their production is
independent of season and graphical conditions with controllable and
predictable yield [5]. In nature, a great number of microorganisms e.g.
yeast, fungi, algae, protozoa and bacteria produce pigments (Fig. 1).
Nevertheless, appropriate species should satisfy some criteria: i) ability to
use a variety of C and N sources, ii) tolerance to growth conditions (e.g.
pH, temperature, nutrient concentration), iii) providing expected color at
reasonable yield, iv) non - toxic and non-pathogenic product, and v)
simple extraction of pigment from cell biomass if not excreted [2].
87
Microbes as source of natural color: current trends and future perspectives
Figure 1. Representation of various colors producing microorganisms on a Petri dish
[6, 7].
Microbes as a source of natural pigment: Basics and brief
idea
Pigment producing microorganisms like, bacteria offers certain
distinctive advantages, owing to their short life cycle, non-sensibility to
season and climate, potentiality to produce pigments of different colors and
shades, easier scale-up production of pigments, etc. Some examples of the
pigment producing bacterial species include Flavobacterium sp. which
produces the yellow pigment zeaxanthin, Agrobacterium aurantiacum (pinkred pigment, astaxanthin), Micrococcus sp. (various colored pigments,
carotenoids), and Pseudomonas aeruginosa (blue-green pigment),
Serratiamarcescens (red pigment), Chromobacterium sp. (violet pigment)
and Rheinheimera sp. (blue pigment) [8].
Factors affecting microbial pigment production
Stress condition
Pigment
Microorganism
References
Monascus pigment
β-Carotene
Carotenoids
Monascus sp.
Rhodutorula
R. rubra
R. gultinis
Pseudomonas sp.
[4, 5, 9, 10]
Temperature
25-28°C
5-26 °C
42 °C
29-32 °C
35-36°C
88
Vivek Prakash Pankaj & Roshan Kumar
Continued
pH
5.5-6.5,
4.0-4.5
β-Carotene
Carotenoids
Monascus sp.
Rhodotorula
R. rubra
[4, 9, 10, 11]
Carotenoids
Monascus pigment
Phaffia rohodozyma
R. lectis
Rhodutorula
Lactobacillus helveticus
R. gultinis
[1, 4, 10]
Metarhodopsin
Halorubrum sodomense
ATCC 33755
[12]
Monascus pigment
Rubropunctatin
Monascorubrin
Monascin
Monascus sp.
[11]
Rubropunctamine
Monascorubramine
Rubropunctatin
Monascorubrin
Monascin
Ankaflavin
Carotenoids
Monascus sp.
R. gultinis
[4, 10]
Carotenoids
Monascus ruber
[4]
Carotenoids
R. gultinis
Phaffia rohodozyma
[4, 10, 13]
Carotenoids
Phaffia rohodozyma
Lactobacillus helveticus
R. gultinis
[10, 14]
2.5 -9.5
Carbon source
Glucose
Fructose
Maltose
Lactose
Galactose
Salt source
10-350 mg/ml
Mineral
Zn (2×10-3M and
3× 10-3M)
Nitrogen source
Aluminium chloride
Ammonium nitrate
Glutamate
Potassium nitrate
Moisture content
70%
Light condition
Dark
Sunlight
Incubation Time
7 days
12 Days
Microbes as source of natural color: current trends and future perspectives
89
Some functions of microbial pigments
Protection from UV rays
Act as antioxidant
Protect from extreme heat and cold
Functions as antimicrobial and anticancer
Acquisition of nutrients like iron, nitrogen and carbon
Types and classes of microbial pigments
i.
Microbial pigments can be classified on the basis of origin, color, and
solubility.
ii. On the basis origin:
a) Bacterial pigments: It includes bacterium Flavobacter produce
zeaxanthin, Rhodococcus produce canthaxanthin.
b) Fungal pigments: It includes Penicillium, Neurospora and
Rhodotorula yield β-carotene.
c) Algal Pigments: It includes Dunaliella of Chlorophyta produce
β-carotene, Rhodophyta contains phycoerythrins and phycocyanin
iii. On the basis of color: On the basis of color pigments are grouped as in
three pigments as depicted in fig. 2.
iv. Based on solubility microbial pigments can be classified as:
a) Water soluble: These pigments are soluble in water, such as
anthocyanins, xanthophylls etc.
b) Fat soluble: These pigments are soluble in fat, such as canthaxanthin
and carotenes etc.
Figure 2. Classification of pigment on color basis.
90
Vivek Prakash Pankaj & Roshan Kumar
Source of pigments
A number of algae, yeasts, molds and bacteria are excellent source of
pigments. Following criteria should be fulfilled by suitable species for
production of pigments: a) ability to use a wide range of C and N sources; b)
should have tolerance to pH, temperature, mineral concentration and possess
moderate growth conditions; c) reasonable color yield; d) should be non-toxic
and non-pathogenic; e) easily separate from cell mass [1] and potential
microbial sources used for biopigment production as shown in table 1.
Table 1. Potential microbial sources used for bio-pigment production [15, 16]
Name of the microorganism
Pigment
Penicilliumoxalicum
Penicilliummelinii
Bacteria
Riboflavin
Melanin
Canthaxanthin
Violacein
Canthaxanthin
Violacein
Pyocyanin
Prodigiosin
Prodigiosin
Melanin
Prodoginine
Mold
Riboflavin
Physcion
Lycopene
Naphthoquinone
Monascin
Rubropunctatin
Monascorubramine
Arpink Red
Atrovenetin
Cryptococcus sp.
Phaffiarhodozyma
Yeast
Melanin
Astaxanthin
Bacillus subtilis
Bacillus thuringiensisH-14
Brevibacterium sp.
Chromobacterviolaceum
Dietziamaris
Janthinobacteriumlividum
Pseudomonas aeruginosa
Serratia sp.
Streptomyces sp.
Streptomyces virginiae
Streptoverticilliumrubrireticuli
Ashbyagossypi
Aspergillusruber
Blaksleatrispora
Fusariumsp.
Monascus sp.
Color
Yellow
Dark Brown
Orange red
Violet
Red
Violet
Blue green
Red
Red
Dark brown
Red
Yellow
Yellow
Red
Brownish Yellow
Yellow
Orange
Red
Dark red
Yellow
Black
Orange red
91
Microbes as source of natural color: current trends and future perspectives
Table 1. Continued
Rhodotorularubra
Saccharomyces neoformans
var. nigricans
Yarrowialipolytica
Dunaliellasalina
Chlamydomonas
Chlorella sp.
Hemacoccuspluvialis
Carotenoids
Melanin
Red
Black
Melanin
Algae
Carotenoid
Lutein
Brown
Astaxanthin
Actinomycetes
Streptoverticilliumrubrireticuli Prodigiosin
Streptomyces echinoruber
Rubrolone
Red
yellow
Pinkish red
Red
Red
Generation/development of microbial pigment in support of
stress condition and genetic engineering approach
Microbial pigments are produced in variety of conditions such different
range of temperature, humidity, pH and source of nitrogen and carbon. For
example Monascus growth occurs rapidly glucose, fructose, dextrines and
starch. Red pigment produced when there is low initial moisture (26-32%).
Genus Dunaliella accumulates enormous amount of β-carotene, mainly in
response to high light intensity [17]. In recent years Dunalliell sp. mainly
cultivated for carotenoids. Under ideal conditions it can yield 400mg
β-carotene/m2 of cultivation area.
Carotenoids production involve following steps:
i.
Selection of the appropriate substrate: The raw materials utilized
might or not be pretreated depending on the fermentative capacity
of the microorganism and the type of enzymes produced.
ii.
Bioreactor: The bioreactor configuration and operational variables are
crucial for the maximum yields of the process.
iii.
Downstream processing: Production of intracellular pigments is limited
by the complexity of “downstream” processing. Cell disruption is a
critical step to recover intracellular compounds and it affects recovery
yield and carotenoids properties.
92
Vivek Prakash Pankaj & Roshan Kumar
Different microbial pigment and their applications
Microbial pigments have wide applications in day-to-day life, they can be
used as colorants, nutraceutical and food supplements. They are also used in
cosmetics, medicines and biotechnological processes. Various roles of
pigments are:
Pigments as indicators: Violet pigment bacteria (Flexibacter and
Sporocytophaga) indicates polluted drinking water. Blue pigment bacteria
(Vogesellaindigofera) indicates chromium contaminated sites. Phototropic
brown bacteria Chlorobiump haeovibroides indicates the hypoxic condition.
Pigments in food and nutrition: β-Carotene is a precursor of vitamin A. it is
also have applications in beverages such as orange drinks, as solution or
suspensions in vegetable oils, baked products. Application of microbial
pigments used in food industry as shown in table 2.
Pigments in disease control and human health: Eating of carotene rich
yellow and green leafy vegetables improves the vitamin A pool size and
hemoglobin content in the body. Lutein, zeaxanthin and xanthophyll in corn,
kale and spinach believed act as protectant of age related macular
degeneration. Astaxanthin helps in cardiovascular disease prevention and
immune system boosting. Prodigiosin from Serratiamarcescens, Vibrio
psychroerythrous, and Pseudomonas magneslorubra have
been
reported
as antifungal, immunosuppressive, and antiproliferative agents. Pigment
producing microorganisms and their proposed bioactivities as shown in table 3.
Table 2. Microbial pigments and their use in food industry [15, 18, 19].
Microorganisms
Pigment
Application in food
Xanthophyllomycesdendrorhous
Astaxanthi
Feed supplement for salmons, crabs,
shrimps, chickens, and egg production
Neospongiococcumexcentricum
Flavobacterium
Zeaxanthin
Zeaxanthin
Blakesleatrispora
Spongiococcumexcentricum
Monascus sp.
Lycopene
Lutein
Ankaflavin
Colorant for poultry and fish
As an additive in poultry feed to increase
yellow color of animal’s skin and egg yolk
Colorant in cosmetic and food industry
Food colorant
Poultry feeds
Color supplement
Pseudomonas aeruginosa
Colorant in beverages, cakes,
confectionaries, pudding, decoration
of food items
93
Microbes as source of natural color: current trends and future perspectives
Pigments and the immune system: Carotenoids is known to modulate the
immunological reactions. Pigments enhance specific and nonspecific immune
functions. Prodigiosin act as immunosuppressant, Phyocyanin from
Pseudomonas sp. helps in cytotoxicity, neutrophil apoptosis.
Table 3. Pigment producing microorganisms and their proposed bioactivities [18].
Srno.
Pigment
Color
Microorganism
Activities
Bacteria
1
Astaxanthin
Pink-red
Haematococcuspluvialis,
Agrobacterium aurantiacum
Antioxidant,
photoprotectant,
Anti-cancer,
Anti-inflammatory
2
Canthaxanthin
Orange
Bradyrhizobiumsp.
3
Cycloprodigiosin
Red
Pseudoalteromonasdenitrificans
4
Granadaene
Orange–red
Streptococcusagalactiae
Antioxidant,
Anti-cancer
Anti-plasmodial,
Anti-cancer
Antioxidant,
detoxifyROS
5
Heptylprodigiosin
Red
α-Proteobacteria
Anti-plasmodial
6
Indigoidine
Blue
Corynebacteriuminsidiosum
Anti-microbial,
Phaeobactersp
7
Prodigiosin
Red
Serratiamarcescens,
Pseudoalteromonasrubra
8
Pyocyanin
Blue,green
Pseudomonassp.
Anti-cancer,
DNA cleavage,
Immunosuppressant
Cytotoxicity,
Neutrophilapoptosis,
Ciliarydysmotility,
Pro-inflammatory
9
10
Rubrolone
Scytonemin
11
Staphyloxanthin
12
Tryptanthrin
13
Undecylprodigiosin
14
Streptomycesechinoruber
Cyanobacteria
Golden
Anti-inflammatory,
Anti-proliferative
Staphylococcusaureus
Antioxidant,
detoxifyROS
Cytophaga/
FlexibacteriaAM13,1Strain
–
Red
Streptomycessp.
Anti-bacterial,
anti-oxidative
Violacein
Purple
Janthinobacteriumlividum,
Pseudoalteromonastunicate,
Pseudoalteromonassp.,
Chromobacteriumviolaceum,
Antioxidant,
detoxifyROS
15
Xanthomonadin
Yellow
Xanthomonasoryzae
Protection
againstphotodamage
16
Zeaxanthin
Yellow
Staphylococcusaureus,
Flavobacteriumsp.,
ParacoccusZeaxanthinifaciens,
SphingobacteriumMultivorum
94
Vivek Prakash Pankaj & Roshan Kumar
Table 3. Continued
Fungi
17
Ankaflavin
Yellow
Monascusspp.
Anti-tumor,
Anti-inflammatory
18
Anthraquinone
Red
Penicilliumoxalicum
Anti-fungal,
virucidal
19
Canthaxanthin
Orange,Pink
Monascusroseus
Antioxidant,
Anti-cancer
20
Lycopene
Red
FusariumSporotrichioides
,Blakesleatrispora
Antioxidant,
Anti-cancer
21
Monascorubramin
Red
Monascusspp.
Anti-micrbial,
Anti-cancer
22
Naphtoquinone
Deepbloodred Cordycepsunilateralis
Anticancer,Antibacterial,Trypanocidal
23
Riboflavin
Yellow
Ashbyagossypi
Anti-cancer,antioxidant,protection
24
Rubropunctatin
Orange
Monascusspp.
Anti-cancer
25
β-carotene
Yellow-orange Blakesleatrispora,
Fusariumsporotrichioides,
Mucor,circinelloides,
Neurosporacrassa,
Phycomyces,Blakesleeanus
26
Astaxanthin
Red
Algae
Haematococcuspluvialis
27
β-carotene
Orange
Dunaliellasalina
Anti-cancer,
Antioxidant,
suppression
of cholesterol
synthesis
Antioxidant,
photoprotectant,
Anti-cancer
Anti-cancer,
Antioxidant
Yeast
28
Astaxanthin
Red,Pink-red
Phaffiarhodozyma,
Xanthophyllomyces,
Dendrorhous
Antioxidant,
photoprotectant,
Anti-cancer,
Anti-inflammatory
29
Melanin
Black
Saccharomyces,Neoformans
–
30
Torularhodin
Orange-red
Rhodotorulaspp.
Antioxidant,
Anti-microbial
Archea
31
Canthaxanthin
Orange
32
Hemozoin
Brown–black
HaloferaxAlexandrines
Antioxidant,
Anti-cancer
Protozoan
Plasmodiumsp.
–
Microbes as source of natural color: current trends and future perspectives
95
Recent trends of microbial pigment
Pigments are inseparable component of human life as they are involve in
every aspect such as health, disease control and aesthetics etc. In recent
times, demand for natural pigment substance especially from microbes have
been increased. They have many industrial applications, coloring materials
in food industries, in pharmacy and aqua culture industries, also used as
fluorescent markers in biochemical assays.
There is significant growths seen in demand of naturally derived color
due to improvements are seen in technology and industrial setups. A study
on dyes and organic pigments, the worldwide organic colorants market share
is projected to increase from 4.9% in 2003 to $10.6 billion in 2008. A report
from Mintel and Leatherhead Food Research the global market for food
color was approx. $1.55 billion in 2011 [20].
The market share of microbes and microbial products seems to have a
significant and have huge commercial potential in the future demand for safe
and naturally occurring (edible) coloring agents has tremendously increased
in response to carcinogenic and teratogenic nature of synthetic coloring
agents. There are no reliable published statistics on the size of the color
market, however, on a global scale a reasonable estimate would be US$940
million. Presently, the cost of the natural colors is higher than that of
synthetic colors, but this barrier can be overcome by the mass biotechnical
production of the natural colors, in that way, the cost can be bring down.
(Commission on Genetic resources for Food and Agriculture,
2013) [19].
Future perspective and scope of advancement of microbial
pigments
There is serious need of alternate colorants that are natural, cheaper
and biodegradable and without production of unmanageable intermediates
when they enter the ecosystem. There is a growing interest in
microorganisms as a potential alternate source of colorants used in food
industry. In this way, biotechnology may play an important role for large
fermentation of natural bio-colorants. Recent studies prominently projected
the value of natural colorants over synthetic colors. 2011 saw a global sale
of $600 million, an increase of 29 % from 2007. Many microbial pigments
not only used as coloring agents in food and cosmetic industry but also act
as anticancer, anti-inflammatory anti-microbial and anti-oxidant. There is a
96
Vivek Prakash Pankaj & Roshan Kumar
huge demand for colorants in textile, plastic, paint, paper and printing
industry [17].
Using microbial pigments in food processing have huge economic
potential. But using it has challenges due to its high cost, lesser stability
and change in shades due to pH change. In recent times genetic
engineering of microorganisms have improved the fermentation
technology but extensive research is needed for the production of nontoxic
microbial pigments [20]. Generation of various from industrial and
domestic wastes is very promising as it can meet ever -increasing demand
for safe and natural colors. Microbial pigments have huge potential for
meeting the consumer demand as they are independent on weather
conditions, have fast growth.
Conclusion
Pigments are commonly used in numerous products, for example,
food, coloring paint, animal feed, plastic, fabric, cosmetics, and medicine.
Accordingly, synthetic and natural pigments have been immensely used in
various industries. Pigments are responsible for the wide spectrum of
colors in various objects. They are often associated with quality, attractive
appearance, and sensory properties. In recent years, the utilization of
natural pigments in manufacturing sectors e.g. animal feed, food, dye,
textile, cosmetic and pharmaceutical has been increasing due to the
demands by the consumers to replace synthetic dyes. The various benefits
of producing pigments from microorganisms comprises of independence
from weather conditions, easy and fast growth, colors of different shades
and growth on cheap substances and have no negative effect on
environment i.e., eco-friendly. Advancement in stability, safety and
solubility can definitely make extensive use of microbial pigments in the
textile, paper and food industry.
Acknowledgement
All authors want to say thanks of their respective departments or
institutes.
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