flour and breads and their fortification in health and disease prevention || amaranth: potential...

CHAPTER 10

Amaranth: PotentialSource for FlourEnrichment
Narpinder Singh1, Prabhjeet Singh21 Department of Food Science and Technology, Guru Nanak Dev University, Amritsar, India2 Department of Biotechnology, Guru Nanak Dev University, Amritsar, India
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CHAPTER OUTLINE

101

List of Abbreviations 101Introduction 101Grain Characteristics 102Grain Composition 102Food Applications 105Grain Protein Characteristics 106Nutraceutical Properties ofAmaranth Proteins 108

our and Breads and their Fortification in Health and Disease Prevention. DOI: 10.101

opyright � 2011 Elsevier Inc. All rights reserved.

Transgenic Applications 108Technological Issues 109Summary Points 109Acknowledgment 110References 110

LIST OF ABBREVIATIONS

AmA Amaranth albuminCaMV Cauliflower mosaic virus

GI Glycemic index

PAGE Polyacrylamide gel electrophoresisSDS Sodium dodecyl sulfate

INTRODUCTION

Amaranthus or amaranth, a traditional Mexican plant, is a cosmopolitan genus of herbs with

approximately 60 plant species, the majority of which are wild (Stallknecht and Schulz-

Schaeffer, 1993). Amaranthus plants have inflorescences and foliage with different colors,ranging from purple to red and gold. It is a dicotyledonous plant and is also considered

a pseudocereal because of its properties and characteristics (Breene, 1991). Amaranth is

generally cultivated in arid zones where commercial crops cannot be grown. Amaranthus hasa good capacity to produce high biomass and is used as grains, leafy vegetables, and orna-

mentals. Several species of amaranth are often considered as weeds. Amaranthus cruentus and

A. hypochondriacus are the species that are primarily cultivated for grain, whereas A. blitum,

6/B978-0-12-380886-8.10010-8

A. hypocondriacus A. caudatus

FIGURE 10.1Grains of different amaranth varieties

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SECTION 1Flour and Breads

A. dubius, A. tricolor, A. lividus, and A. spinosus are used as vegetables. Amaranthus tricolor and

A. caudatus are also grown for ornamental or decorative purposes. Amaranthus viridis,

A. retroflexus, A. hybridus, A. gracilis, A. gangeticus, A. paniculatus, and A. graecizans are wild types.The leaves of Amaranthus are a potential alternative source of betalains because of their

betacyanin pigments, and they also show anticancer activity.

GRAIN CHARACTERISTICSAmaranth grain is nearly spherical, approximately 1 mm in diameter, and varies in color from

creamish yellow to reddish. It also has a unique composition of protein, carbohydrates, andlipids. Amaranthus hypochondriacus produces creamish yellow grains, whereas the grains of A.

caudatus are red (Figure 10.1). Hunter color L*, a*, and b* values are approximately 62e68,

5.5e6.7, and 21.2e23.7, respectively, for A. hypochondriacus, and they are 49e51, 13e13.8, and10.6e13.2, respectively, for grains of A. caudatus. Amaranth grain structure differs significantly

from that of cereals such as maize and wheat. Amaranth seeds have a circular-shaped embryo

or germ, which surrounds the starch-rich perisperm and, together with the seed coat, repre-sents the bran fraction, which is relatively rich in fat and protein (Bressani, 1994). Bran

fraction is proportionally higher in amaranth seeds than in common cereals, such as maize

and wheat, which explains the higher levels of protein and fat present in these seeds (Bressani,1994).

GRAIN COMPOSITIONAmaranth grain has approximately 62e65% starch, which is made up of amylose and

amylopectin. Amylose is a linear chain molecule, whereas amylopectin is highly branched,

consisting of a main chain of (1e4)-linked a-D-glucose along with short chains of (1e6)-a-D-glucose-linked branches. Amaranth starch has a low amylose content, ranging between 2 and

12%, that varies by genotype. Amaranth starch granules have diameters ranging between 0.5

and 2.5 mm, similar to rice but smaller than those found in starches of other cereal grains.A comparison of amaranth starch granules with those of wheat, rice, and potato is illustrated in

Figure 10.2. Amaranth starch has polygonal-shaped granules and displays an A-type X-ray

pattern, which is similar to those of wheat, rice, and maize starches. Amaranth starch showsgreater crystallinity compared to wheat starch, with strong reflections at 2�q ¼ 15.1�, 17.2�,18.1�, and 23.2� (Figure 10.3). An additional peak at 2�q¼ 20.0� is usually present, indicatingthe presence of amyloseelipid complexes. Amaranth starch shows intercultivar variability incrystallinity. Its starch has a pasting temperature and a gelatinization onset temperature of

Wheat starch (x1,000) Potato starch (x400)

Rice starch (x2,000) Amaranth starch (x7,000)

FIGURE 10.2Scanning electron micrographs of different starches

CHAPTER 10Amaranth: Potential Source for Flour Enrichment

103

69e72� and 60e77�C, respectively. The difference in pasting behavior among starches from

different genotypes has been observed due to differences in amylose content, crystallinity, and

the presence or absence of amyloseelipid complexes. The pasting curve of starch separatedfrom two genotypes of A. hypocondriacus is illustrated in Figure 10.4. Its starch usually produces

5 10 15 20 25 302θ (°)

Relative In

ten

sity

Wheat

Amaranth

FIGURE 10.3X-ray diffractograms of wheat and amaranth starch. Source: N. Singh, unpublished data.

IC-540860

RMA-22

0

500

1000

1500

2000

2500

3000

0 3 6 9 12Time (min)

Visco

sity (cP

)

0

20

40

60

80

100

Tem

peratu

re (°C

)

FIGURE 10.4Pasting curves of starch separated from different amaranth genotypes. Source: N. Singh, unpublished data.


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sharper peaks with lower setback and higher breakdown, similar to that of normal and waxy

corn starches.

Amaranth grain is a high glycemic food, attributed to its small starch granule size, low amylose

and resistant starch content, along with a tendency to completely lose its crystalline and

granular starch structure during heating. The glycemic indexes of amaranth and other cerealgrains and foods are compared in Table 10.1. The glycemic index defines carbohydrates present

in different foods on the basis of the postprandial level of blood glucose (Jenkins, 2007). The

relationship between the rate of in vitro digestion and the glycemic response to food is well-known. Raw amaranth seeds had a rapidly digestible starch content of 30.7% (dry weight

basis) and predicted glycemic index of 87.2 (Capriles et al., 2008). The starch digestibility of

cooked, extruded, and popped Amaranth seeds was 92.4, 91.2, and 101.3, respectively,compared to white bread, and approximately 106 for flaked and roasted seeds.

Amaranth grains are enriched with various minerals, such as calcium, phosphorus, iron,

potassium, zinc, and vitamin E and B complexes. Amaranth is a rich source of polyphenols(flavonoids) with relatively high antioxidant activity. Caffeic acid, p-hydroxybenzoic acid, and

ferulic acid are the main phenolic compounds in amaranth grains (Klimczak et al., 2002). The

presence of polyphenols such as rutin (4.0e10.2 mg/g flour) and nicotiflorin (7.2e4.8 mg/gflour) in A. hypochondriacus varieties grown in the Mexican highlands zone has also been

reported (Barba de la Rosa et al., 2009).

The concentrations of calcium, magnesium, and oxalate in grains of 30 amaranth genotypes of

A. cruentus, A. hybrid, and A. hypochondriacus have been studied (Gelinas and Seguin, 2007).

Concentrations of calcium andmagnesium in the grains were 134e370 and 230e387mg/100 g,respectively, whereas the oxalate content varied from 178 to 278 mg/100 g. Although dietary

oxalate is a potential risk factor for kidney stone development and lowers the availability of

calcium and magnesium, most of the oxalates in the amaranth grains are in insoluble formand, thus, absorption may be low. However, this needs to be confirmed by bioavailability

investigations.

The dietary fiber and lipid contents in amaranth grain were 8e17 and 3.0e10.5%, respectively.

Although amaranth grain contains higher lipids than most of the cereals, the composition of

its oil is quite similar to that of cereals, being high in unsaturated fatty acids (approximately77%). Amaranth oil contains mainly linoleic acid but also tocotrienols, which are associated

TABLE 10.1 Glycemic Index (GI) of Various Foods

Food GI

Amaranth grain (raw)a 87White breada 94Amaranth grain (popped)a 101Amaranth grain (roasted)a 106Amaranth grain (flaked)a 106Amaranth grain (extruded)a 91Amaranth grain (popped)b 97Pearl barleyb 25Sweet cornb 53White riceb 64Brown riceb 55Parboiled riceb 47Bulgur wheatb 48Cornflakesb 84Puffed wheatb 74Wheat breadb 70Wholemeal breadb 69Lentilsb 28Soybeanb 18Baked beans (canned)b 48

aData from Capriles et al. (2008). Glycemic index (predicted) determined

using equation ¼ 39.71 þ 0.549 (hydrolysis index) of Goni et al. (1997).bData from Foster-Powell et al. (2002); reference food is glucose.


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with cholesterol-lowering activity in mammalian systems (Becker, 1989). Amaranth grain oil
contains a significant amount (up to 8%) of squalene (Sun et al., 1997), which has importantdirect or indirect beneficial effects on health and is also an important ingredient in cosmetics.

Therefore, amaranth oil has the potential to replace other squalene sources such as shark and

whale, which are endangered species.

FOOD APPLICATIONSThe small starch granule size and composition have been suggested to be responsible forunique gelatinization and freeze/thaw characteristics that could be exploited by the food

industry to develop various products (Becker et al., 1981). Amaranth starch can be used in

many food preparations, such as custards, pastes, and salads, and nonfood applications, suchas cosmetics, biodegradable films, paper coatings, and laundry starch. Amaranth flour is used

as a thickener in gravies, soups, and stews. Sprouted amaranth is used in salads. The cooking of

amaranth improves its digestibility and absorption of nutrients. Amaranth flour lacks glutenproteins present in wheat; hence, it is not suitable for bread making. It is blended with

wheatmeal/flour in the preparation of unleavened flat bread known as chapattis in India and

tortillas in Latin America. Amaranth flour is also used in the preparation of biscuits, muffins,pancakes, pastas, flat breads, extruded products, etc. In India, the grains are most commonly

used in the form of candy known as laddoos.

In comparison to amaranth grain, vegetable amaranth has received less attention by

researchers. Vegetable amaranth is used as a delicacy or a food staple in many areas of the

world. Amaranthus leaves are used as a vegetable in the northern states of India. However, itsuse is limited to “Sag,” which is prepared by cooking with mustard leaves along with garlic,

ginger, green chilies, and salt. Vegetable amaranth is better tasting than spinach and is

substantially higher in calcium, iron, and phosphorous.


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GRAIN PROTEIN CHARACTERISTICSCereals are normally deficient in lysine and tryptophan, whereas legume proteins show defi-

ciency of sulfur-containing amino acids, namely cysteine and methionine. Amaranth proteins,on the contrary, contain significant amounts of both sulfur amino acids and lysine. Amaranth

grains have higher protein (11e17%) than most of the cereal grains. Amaranth is an appro-

priate grain for people who are allergic to gluten. The germ and endosperm of amaranth graincontain 65 and 35%, respectively, of protein compared to an average of 15 and 85%,

respectively, in most of the cereals. The amino acid composition of different amaranth protein

fractions is given in Table 10.2. Albumins and globulins are relatively rich in lysine and valine,essential amino acids, whereas glutenins are high in leucine, threonine, and histidine. In

addition to amino acid composition, the protein quality also depends on bioavailability or

digestibility. Protein digestibility, available lysine, net protein utilization, and protein effi-ciency ratio, which are indicators of protein nutritional quality, are substantially higher for

amaranth proteins compared to cereal grains (Guzman-Maldonado and Paredes-Lopez,

1999). Therefore, amaranth proteins are a promising food ingredient, capable of comple-menting and supplementing cereal or legume proteins (Guzman-Maldonado and Paredes-

TABLE 10.2 Amino Acid Composition of Amaranth (Amaranthus hypochondriacus L.)Protein Fractions

Amino Acid

Protein Fractions

Meal Albumins Globulins Prolamins Glutelins

Isoleucinea d 3.7 4.2 6.2 5.8Leucinea d 5.7 5.7 5.7 10.5Lysinea d 7.6 6.7 4.2 4.6Methioninea d 4.1 3.4 7.4 3.1Cysteinea d 5.9 3.9 6.5 6.2Phenylalaninea d 5.1 5.0 9.0 6.8Tyrosinea d 3.3 4.3 4.0 3.8Threoninea d 3.9 4.1 3.2 8.6Valinea d 4.5 4.7 2.7 3.8Histidinea d 2.5 1.1 1.1 4.7Alaninea d 5.1 4.0 4.7 3.6Argininea d 8.1 9.5 9.4 2.7Aspartic acida d 6.2 8.7 6.2 6.1Glutamic acida d 17.5 17.3 13.4 13.2Glycinea d 6.2 6.6 4.4 4.9Prolinea d 3.7 3.9 4.7 4.6Serinea d 4.8 4.9 5.1 5.3Serineb 7.3 6.4 7.7 8.0 9.0Glycineb 10.7 10.5 13.9 10.7 10.3Histidineb 3.0 2.3 2.3 1.8 2.4Arginineb 7.3 8.9 9.3 6.8 8.5Threonineb 5.1 3.4 4.0 7.2 5.4Alanineb 6.6 6.2 5.4 8.6 6.3Prolineb 5.7 5.0 4.0 4.5 5.9Tyrosineb 1.9 2.9 2.8 3.0 3.0Valineb 5.9 4.0 5.0 4.5 5.0Isoleucineb 3.9 3.5 4.0 4.5 5.0Leucineb 6.2 5.5 6.0 10.0 8.0Phenylalanineb 3.4 3.0 2.0 3.9 4.3Lysineb 5.7 6.6 7.0 6.7 4.2

aExpressed as grams of amino acids/100 g of crude protein (Barba de la Rosa et al., 1992).bExpressed as molar percentage (Segura-Nieto et al., 1992).


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Lopez, 1999). The protein digestibility corrected amino acid score of amaranth whole flour is

higher (0.64) than those of wheat (0.40) and oat (0.57) (Bejosano and Corke, 1998). Anaverage protein digestibility of 74.2% for raw amaranth wholemeal flour was reported

(Bejosano and Corke, 1998). Thermal processing improves protein digestibility due to

opening of carbohydrateeprotein complexes and/or the inactivation of antinutritional factorssuch as trypsin inhibitors (Bejosano and Corke, 1998).

Contrary to legumes and cereals, in which the grain proteins generally serve as storagemolecules for the growing plantlets, the amaranth grain consists of albumins, which are

usually biologically active, in the highest amount. According to the Osborne classification

(Osborne, 1924), the amaranth grain consists of three major fractionsdalbumins (51%),globulins (16%), and glutelins (24%)dand aminor fractiondthat is, alcohol-soluble fraction

or prolamine between 1.4 and 2.0% (Gorinstein, Moshe, et al., 1991; Martinez et al., 1997),

whereas legume grain contains salt-soluble globulins as the major storage protein fraction.Cereals such as maize and wheat, on the contrary, contain alcohol-soluble prolamins as the

major storage proteins (Gorinstein, Denue, et al., 1991). The characterization of grain proteins

of amaranth has been carried out using different techniques of extraction and electrophoresis(Barbra de la Rosa, Gueguen, et al.,1992; Barbra de la Rosa, Paredes-Lopez, et al.,1992; Gori-

nstein, Denue, et al., 1991; Gorinstein, Moshe, et al., 1991). On the basis of differential

extraction, the amaranth albumin was classified as albumin 1 and 2 (Konishi et al., 1991).Albumin 1 is extractable with water and/or saline solution, whereas albumin 2 is extractable

with water after the removal of albumin 1 and globulin with saline solution. Albumin 2

consists of amarantin as the major protein component (Martinez et al., 1997). The subunit sizeof albumin proteins varied from 10 to 37 kDa (Barbara de la Rosa, Gueguen, et al., 1992;

Gorinstein, Moshe, et al., 1991), with low-molecular-weight subunits being more abundant

(Segura-Nieto et al., 1992). Barbara de la Rosa et al. (2009), however, differentiated thealbumin fraction into two groups of proteins corresponding to approximately 18 kDa and

between 40 and 80 kDa. The proteins of approximately 18 kDa were termed as methionine-

rich proteins due to their high methionine content (16e18%) (Segura-Nieto et al., 1994).

Determination of sedimentation coefficient by centrifugation has also been widely used to

characterize the proteins. On the basis of sedimentation coefficients, the amaranth seedglobulins are categorized into 10S and 12.7S compared to 7/8S and 11/12S for the legume seed

globulins. The electrophoretic behavior of 10S and 12.7S amaranth globulin fractions on

denaturing gel was observed to be similar to that of 7S and 11S storage proteins of legumes andhence referred to as 7S and 11S, respectively (Barba de la Rosa, Moshe, et al., 1992). The higher

sedimentation coefficients of amaranth globulins, as observed on linear sucrose gradients,

suggested that these proteins contain polypeptides of higher molecular weight than thosepresent in 7S and 11S from pea globulins (Segura-Nieto et al., 1992). The 7S and 11S amaranth

seed globulins also differed in their solubility in salt solution, with the former being extract-

able with 0.1 M and the latter with 0.8 M NaCl (Barbara de la Rosa et al., 2009). The 7Sglobulin fraction of amaranth grain was characterized by the presence of a main band of 38

kDa and lacked disulfide bridges, whereas the 11S-like globulins consisted of both acidic

(35e38 kDa) and the basic polypeptides (22e25 kDa). These results are in agreement withprevious studies that found that globulins consisted of polypeptides of heterogeneous sizes, as

demonstrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE)

analyses (Segura-Nieto et al., 1992). However, these observations contradicted the findings ofGorinstein, Moshe, et al. (1991), who reported that the globulin was composed of poly-

peptides of only 14e18 kDa. Martinez et al. (1997) proposed that both 7S and 11S globulins

correspond to one type of globulin, whereas polymerized globulins (albumin 2) and glutelinscorrespond to two other types of globulins. However, this notion needs to be verified by

establishing sequence homology and by proving a common genetic origin of globulin,

albumin 2, and glutelin.


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The most important component of globulins is amarantin, which alone constitutes 90% of thetotal globulins and approximately 19% of the total grain protein (Romero-Zepada and

Paredes-Lopez, 1996). Amarantin is a homohexameric molecule of approximately 300e400

kDa comprising subunits of approximately 59 kDa. Each of the subunits consists of an acidicpolypeptide of 34e36 kDa and basic polypeptide of 22e24 kDa linked by disulfide bonds.

The additional subunit of 54 kDa present in amarantin has been proposed to act as an inducerof polymerization (Martinez et al., 1997).

The amaranth glutelin showed high similarity with 11S globulins (Abugoch et al., 2003) and

comprised three major polypeptides groups of 22e25, 35e38, and approximately 55 kDa. It islikely that both glutelins and 11S globulins may belong to the same structural gene family. The

differences in composition of alcohol-soluble proteins have been reported in various studies.

Gorinstein, Moshe, et al. (1991) observed only low-molecular-weight subunits of 10e20 kDaon SDS-PAGE analysis of the alcohol-soluble proteins, whereas Barba de la Rosa, Gueguen,

et al. (1992) reported the presence of subunits of both low and high molecular mass.

Furthermore, great similarity between the electrophoretic pattern of reduced prolamine andglutelins was also observed in the latter study. The lack of consistency in the composition of

various protein fractions of amaranth grain, evident from the literature, may be due to the

different procedures used in the extraction and analyses. In view of the nutritional importanceof amaranth, it is imperative that a systematic study be undertaken to analyze the proteome of

amaranth leaves and grains by employing the latest techniques of proteomics. This will enable

the identification and characterization of nutritionally important proteins, the genes for whichcan then be cloned and expressed heterologously in other crops to enhance their nutritive

value.

NUTRACEUTICAL PROPERTIES OF AMARANTH PROTEINSThe albumins and globulins are rich in lysine and valine, whereas prolamins have a compar-

atively higher content of methionine and cysteine. Glutelins, on the contrary, contain higherlevels of leucine, threonine, and histidine. Compared to legume grain albumins, which

contain several antinutritional factors, the amaranth albumin fraction is considered safe. The

amaranth albumin fraction is comparable with egg-white proteins and can be used as an eggsubstitute in different products. The 11S globulin fraction is rich in peptides of angiotensin-

converting enzyme inhibitor, whereas the glutelin fraction contains antihypertensive activity as

well as the anticarcinogenic lunasin-like peptide (Silva-Sanchez et al., 2008), thus signifying itsnutraceutical properties.

TRANSGENIC APPLICATIONSImproving the balance of essential amino acids in important crop plants remains one of themajor objectives of plant breeders. Transgenic technology presents an attractive alternative

for improving the nutritional quality of grain proteins. Heterologous transgenic expression

of storage protein genes with higher levels of limiting amino acids has been reported.Transgenic expression of high levels of a particular amino acid may adversely affect the

normal physiology of seed development or produce seeds with a biased amino acid

composition. Therefore, expressing a gene for a heterologous protein with a balanced aminoacid composition is a better alternative. A gene of a 35-kDa albumin protein (AmA1), which

is expressed during early to mid-maturation stages of embryogenesis in the amaranth seed,

has been cloned (Raina and Datta, 1992). The amino acid composition of this protein meetsthe World Health Organization’s recommended values for a highly nutritional protein

because it is rich in various essential amino acids. Potato is the most important noncereal

crop in terms of total global food production; therefore, transgenic expression of this gene inthe tubers of this crop has been achieved. Heterologous expression of AmA1 under

constitutive (CaMV 35S promoter) and tuber-specific promoter (granule-bound starch


synthase) in potato resulted in significant enhancement in total protein content with anincrease in essential amino acids (Chakraborty et al., 2000). Furthermore, the growth and

production of tubers in transgenic plants were also higher compared to those of control

plants.

Maize, which is a staple food in many countries but lacks essential amino acid in the grains,

has also been targeted for heterologous expression of amaranth proteins to enhance thenutritional quality of its protein. A complementary DNA of an 11S globulin storage protein,

amarantin, which has a high content of essential amino acids, was expressed in maize

under CaMV 35S promoter and an endosperm-specific promoter (rice glutelin-1) (Rascon-Cruz, 2004). Heterologous expression of this gene resulted in an increase of 18% in lysine,

28% in sulfur-containing amino acids, and 36% in isoleucine, in addition to a 32%

increase in total seed protein. Furthermore, the heterologously expressed protein wasdigested by simulated gastric and intestinal fluids, thus confirming the biodigestibility of

the transgenic protein. Therefore, these studies validate the potential of using different

amaranth genes for supplementing and complementing the proteins in both cereal andnoncereal staple crops. However, detailed analysis of proteomes of different amaranth

species needs to be carried out to identify the candidate gene(s) that can be employed for

transgenic improvement. Furthermore, generation of mutants in amaranth is also requiredto determine the role of specific proteins in growth and development of the plant so that

appropriate improvement of the germplasm can be undertaken through conventional

breeding strategies.

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TECHNOLOGICAL ISSUESThe diversity in composition among different amaranth genotypes necessitates in-depth

characterization of biochemical constituents for its specific applications in the food industry.

The smaller size granules in amaranth starch, which are similar to the size of fat globules ofcow’s milk, can be exploited to mimic fat in a number of food products. Some of the genotypes

have higher polyphenols with higher antioxidant activity, which could also be utilized in the

development of new products. Amaranth grain has the potential to be used in the develop-ment of various food products for people suffering from celiac disease, a disorder that makes

the body intolerant to gluten proteins.

SUMMARY POINTS

l Amaranth grain is a good source of dietary fiber and has a high glycemic index. It is low in

resistant starch, and its starch has uniquely small granules with a low tendency toward

retrogradation.l Grain amaranth has a higher protein content than most of the cereal grains and is an

appropriate food for people who are allergic to gluten.

l Amaranth grain oil is quite similar to that of cereals, being high in unsaturated fatty acidsand containing mainly linoleic acid. Its oil also contains tocotrienols that are associated

with cholesterol-lowering activity in mammalian systems. Amaranthus grain oil contains

a significant amount of squalene.l Amaranth grain proteins are composed mainly of three major fractionsdalbumins,

globulins, and glutelinsdwith little or no storage prolamin. Amarantin is the most

important component of globulins and constitutes 90% of the total globulins andapproximately 19% of the total grain protein.

l Heterologous expression of the amarantin gene (AmA1) in potato resulted in significant

enhancement in total protein content with an increase in essential amino acids.


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l Amaranth is a good source of minerals such as iron, magnesium, phosphorus, copper, andmanganese. Because of its unique composition, it is an attractive food complement and

supplement.

AcknowledgmentThe financial assistance to Narpinder Singh from the Department of Science and Technology, Ministry of Science and

Technology, Government of India is acknowledged.

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