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Isolation, Stabilization and Characterization of Xanthophyll from Marigold Flower- Tagetes Erecta-L

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The present paper deals with the chemistry, isolation, separation, characterisation and stabilisation of the Marigold oleoresin and its application as a natural food colorant. Marigold (Tagetes Erecta L), an ornamental plant belonging to the composite family, has a rich source of natural antioxidant-Lutein. A natural pigment, xanthophylls offer an alternative to synthetic dyes as a food colorant, due to its non-toxicity. Chromatographic separations of saponified and unsaponified oleoresin were performed and Trans-Lutein identified as the major constituent. Well-preserved flowers exhibit a high yield of Xanthophyll content (105.19 g/Kg) in contrast to the unpreserved flower sample (54.87 g/Kg), emphasizing the significance of flower preservation in the extraction of xanthophyll. The stability and amount of xanthophyll also increased from 105.19 g/Kg to 226.88 g/Kg on saponification and subsequent purification with Ethylene Dichloride.
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Isolation, Stabilization and Characterization of Xanthophyll
from Marigold Flower- Tagetes Erecta-L
V.B. Pratheesh, Nify Benny & C.H Sujatha
Department of Chemical Oceanography
CUSAT. Kochi-16, Kerala, India
Tel: 91-0484-238-2131 Fax: 91-484-374164
E-mail: dr.sujathach@gmail.com
Abstract
The present paper deals with the chemistry, isolation, separation, characterisation and stabilisation of the Marigold
oleoresin and its application as a natural food colorant. Marigold (Tagetes Erecta L), an ornamental plant belonging to
the composite family, has a rich source of natural antioxidant-Lutein. A natural pigment, xanthophylls offer an
alternative to synthetic dyes as a food colorant, due to its non-toxicity. Chromatographic separations of saponified and
unsaponified oleoresin were performed and Trans-Lutein identified as the major constituent. Well-preserved flowers
exhibit a high yield of Xanthophyll content (105.19 g/Kg) in contrast to the unpreserved flower sample (54.87 g/Kg),
emphasizing the significance of flower preservation in the extraction of xanthophyll. The stability and amount of
xanthophyll also increased from 105.19 g/Kg to 226.88 g/Kg on saponification and subsequent purification with
Ethylene Dichloride.
Keywords: Antioxidant Activity, Colorants, Extraction / Separation, HPLC, Natural Products, Pigments
1. Introduction
Since the early civilizations and in the beginning of the food industry, pigments –natural or synthetic, were used to give
an attractive presentation, perception of freshness, taste, and quality of food. Saffron and other plant species were used
to provide characteristic color and flavor in food. Today, natural colorants are emerging globally due to the perception
of its safer and eco-friendly nature. Nowadays, a trend towards “naturalness” represents a challenge for food
manufacturers, because of its pharmacological applications. Synthetic dyes received faster acceptability due to a wide
range of applications in various fields like food (Torgils et al. 1998) , cosmetic (Calnan 1976), and more importantly in
textile (Savarino et al. 1999 , Paisan et al. 2002) due to ease in dyeing, and reproducibility in shades and overall cost
factor. Natural food colorants can be originally present in the foodstuff, or may be added as an extract to enhance the
natural color. Quality of food is associated with many aspects -color, flavor, and texture, but color can be considered the
most important of them, because of its appealing nature. Color as well gives the key to catalogue a food as safe, with
good aesthetic and sensorial characteristics: the undesirable colors in meat, fruits, and vegetables warn us about a
potential danger or at least of the presence of undesirable flavors, among other reactions. The food industry is therefore,
interested in gaining a better understanding of color generation and color stabilization during the various steps of food
processing. The processed food constitute 60- 65% of total food and the need for the food additives and its improved
shelf life is also increasing. There are some 2500 chemicals that function as food additives that give rise to some 5000
trade name products on a worldwide basis (Scotter.M.J & Castle.L. 2004). However, the natural pigments that are
permitted for human foods are very limited, and the approval of new sources is difficult, because the U.S. Food and
Drug Administration (FDA) considers the pigments as additives, and consequently pigments are under strict regulations
(Delgado-Vargas et al.2000).
A high quality of food and beverages is vital to our physical and mental well being. Of all the food additives in use,
none gives rise to greater controversies than food colors. The readily available coloring matter based on natural
products is of considerable importance since the United States have banned the use of synthetic coloring in foods. In
ancient times tinted amaranth has been used to extract the coloring matter, which is hydrophilic in nature and was used
for the dyeing of drinks, food and other products in Mexico, Bolivia and Ecuador (Gladis et al. 2000). In India and
Mexico, for facial rouge the woman used amaranth juice. This pigment belongs to the group of betacyanines (Attoe. L.J.
& Von Elbe, J.H. 1985, Mabry T.J & Drieiding, A.S.1968) and the betanine have been used as colorants in many types
of food (Pasch, J. H. & von Elbe, J. H .1979). Some of the important plant pigments are carotenoids, Anthocyanins, and
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betalains. Carotenoids are compounds comprised of eight Isoprenoid units (Ip) whose order is inverted at the molecule
center (Delgado-Vargas et al.2000) (Figure: 1). Carotenoids are classified by their chemical structure as: (i) carotenes
that are constituted by carbon and hydrogen; (ii) oxycarotenoids or xanthophylls that have carbon, hydrogen, and,
additionally, oxygen. Also, Carotenoids have been classified as primary or secondary. Primary carotenoids group those
compounds required by plants in photosynthesis (ȕ-carotene, violaxanthin, and Neoxanthin), whereas secondary
Carotenoids are localized in fruits and flowers (Į-carotene, ȕ -cryptoxanthin, zeaxanthin, antheraxanthin, capsanthin,
capsorubin). Anthocyanins are the most important group of pigments, after chlorophyll, which is visible to the human
eye (Harborne et al.1988). Chemically, Anthocyanins (Greek word anthos means a flower, and kyanos, dark blue) are
flavonoids. Anthocyanins (Figure: 2) are substituted glycosides of salts of phenyl-2- benzopyrilium (anthocyanidins).
Chemically, betalain definition embraces all compounds with structures based on the general formula (Figure 3)
therefore, they are immonium derivatives of betalamic acid (Strack et al.1993).
Carotenoids are abundant in fruits and plants and are widely used an antioxidant and may be useful in the prevention of
diseased including cancer. The consumption of lutein and zeaxanthin reduces 40 % of the age related macular
degeneration (seddon 1994). The xanthophylls because of their yellow to orange-red coloration and natural occurrence
in human foods, also finds its use as a food colorant. Therefore there exist a high demand for the significantly pure
Xanthophyll that can be used as a food colorant and a nutrient supplement. Flowers such as Tagetes comprise different
species about 33 in number, helenium, helianthus, sunflower, dandelion and many others. Of these, most concentrated
source of xanthophylls is of the order 4500mg/lb (Verghese, 1998b) in the petals of Tagetes Erecta L (African marigold,
Aztec marigold, Zempasuchil). Marigold flower petals are a significant source of the Xanthophyll and have a much
higher concentration of this pigment compared to other plant materials (Verghese, 1998a). Marigold flower (Tagetes
Erecta L) is a hardy annual branching herb about 60 to 90 cm tall and erect, grown in certain parts of India- Tamil Nadu,
Andra Pradesh , Karnataka as well as in other parts of the World; and is extensively cultivated in temperate climate. It
prefers nourishing soil of pH 7.0 to 7.5 with good water-holding capacity and well-drained fertile sandy loamy soil as
well as a sunny climate. Mexican’s use marigold flower as a traditional medicine and to Romans, an inexpensive food
colorant, a substitute for saffron and it was they who introduced to other parts of Europe. Now a days, the marigold
flower is exclusively used for the Malayali festival “Onam” in Kerala, India and all over the world to make “pookalam”
(flower carpet) (Figure: 4), due to its exotic combination with other vibrant colored flowers.
Depending on the varieties, cultivar and horticulture practices, the yield of flower showed remarkable variations in
number and in flower weight (from 11 to 30 ton/hectare). Although flower is made up of petals, calyx pedicle, seeds
etc., approximately 40% to 50% of the flower consist of petals. Extraction studies of petals and total flower with hexane
showed that only flower petals contain xanthophylls. Calyx contains chlorophyll which in-turn affects absorption of
xanthophylls by broilers and layers (Verghese. J 1998b). Hence, only the petals are used for the isolation of oleoresin.
The main coloring component of Marigold flower is lutein (C40H56O2). Free Lutein hardly exists in the flower and it
naturally occurs in the acylated form (Figure 5). The Lutein ester concentration in fresh Marigold flowers varies from 4
mg/Kg in greenish yellow flowers to 800 mg/Kg in orange brown flowers (Sowbhagya et al. 2004). Dark-colored
flowers contain about 200 times more Lutein esters than the lightcolored flowers. Xanthophyll content varies in the
range of 9 to 11 g/Kg. The concentration of Lutein varies in different shades of marigold flowers, viz.; greenish yellow
to bright yellow and orange brown (Gregory et al.1986). Total Lutein esters have been reported to be in the range of 3.8
to 791 mg/Kg of flower (Sowbhagya et al. 2004). Lutein palmitate is the major ester in the flower. The other esters of
lutein identified in the flower are dimyristate, myristate palmitate, palmitate sterate, and distearate (Table: 1). A purified
extract of marigold petals mainly containing Xanthophylls dipalmitate is marketed as an ophthalmologic agent
(Sowbhagya et al. 2004, Gau et. al. 1983). Lutein is stable in pH range 3 to 9. At extreme pH and in the presence of
light, lutein undergoes isomerization resulting in color loss. Lutein structure consists of conjugated bonds, which when
react with the oxygen present in air, cause oxidation to take place and lead to color loss. Oxidation products of
xanthophylls are mono and di-epoxides, carbonyls, alcohols etc. and extensive oxidation results in bleaching of
carotenoid pigments. To minimize color loss, it is safe to pack lutein-containing products in tin or opaque containers.
Enzymes like lipoxygenase hasten oxidative degradation, which occurs by direct mechanisms. Enzymes first react with
unsaturated or saturated fatty acids producing peroxides, which react with lutein xanthophylls and lead to oxidative
degradation. “Blanching” (98oC/5 min) exhibits an apparent increase in xanthophylls content due to inactivation of
lipoxygenase and also enhances pigment extraction (Sowbhagya et al. 2004, Alam et al. 1968).
Marigold carotenoids have potential as a natural food colorant. The status of marigold, as a source of natural
carotenoids, has been reviewed (Verghese. J 1998a, 1998b). Temperature, pH, light, activity in water is all factors
which affects the stability of the pigment (Pasch, J. H. & von Elbe, J. H .1979). Stability of Xanthophyll pigment
extracted from marigold has been studied by saponifying. Xanthophylls are usually esterified which produces
additional analyses complications and requires both separation and identification. Saponification obtains less complex
mixtures when only non-esterified pigments appear. Another advantage of saponification is chlorophyll destruction in
the saponified samples (Delgado-Vargas et al.2000). Since commercial extracts are valued by their Xanthophyll and
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trans-lutein content, concentration of lutein fatty acid esters in the extract can be enhanced by purification. Xanthophyll
content can be boosted by phase partition between 70% and 90% of hexane, acetone, methanol and ethanol. When
marigold extract was subjected to precipitation using isopropanol removes 65% of the lipids in the extract are removed.
The precipitated fraction contained 51.3% lutein esters and a second precipitation from isopropanol-petroleum ether
(80:20) resulted in a product of much higher purity, more than 65% pure (Sowbhagya et al. 2004). Since the
availability of marigold flower is seasonal, flower preservation becomes vital in the extraction of marigold oleoresin. If
flowers are not properly stored and preserved, Xanthophyll content will decrease. The extraction of xanthophylls
(oleoresin) from marigold flower involves the following stages: ensilage, pressing and drying, Hexane extraction, and
saponification. Of these, the ensilage is considered important in determining the efficiency of the overall process.
Studies were conducted to obtain a relationship between the xanthophylls extraction yield and the efficiency of
marigold flower ensilage (Navarrete-Bolanos et al. 2003). It was reported that during the ensilage, structural cell-wall
degradation of the marigold petals by saprophytic microorganisms associated with the flower resulted in increased mass
transfer during the extraction stage. Such an increase is associated with the level of cellulose synthesized by these
microorganisms.
Numerous methods have been proposed in order to improve both xanthophylls extraction and purification efficiency
(Ausich and Sanders 1997, Khachik 1995, Philip 1997). But many of them have the drawback of high temperature
requirement and long processing times, which can result in the degradation and formation of unwanted isomeric
components (Levi 2001, Madhavi & Kagan 2002). Enzymatic treatment has also been proposed as an alternative stage
to enhance xanthophylls extraction from marigold flower (Delgado-Vargas. F.& Paredes-López. O. 1997,
Navarrete-Bolanos JL.2004). But it too had practical limitations, due to the use of expensive commercial enzyme. It was
reported that solid-state fermentation process of marigold flower showed improved yield efficiency (Soboleva 1978).
Marigold extracts have been commercialized internationally and are used as additives for poultry feed, as they provide
bright colors in egg yolks, skin, and fatty tissues. Marigold extract also finds application in coloring foods like edible
oils, mustard and other salad dressings, cakes, ice cream, yogurt, and dairy products. The extract with only the purified
form with a lutein content of known concentration and a pure crystalline lutein isolated from marigold flower is allowed
for food use. Tagetes meal and extract has been listed with a color index of 75125, and it is allowed in chicken feed
only to a maximum limit of 1% (Vernon-Carter 1996).
2. Material and methods
2.1 Reagents and equipment
All the reagents used were of A.R. grade or the best quality available and milli -Q water was used throughout in the
analysis. A UV-Visible spectrophotometer with 1 cm quartz cell was used for the absorbance measurements and HPLC
was used for the separation and analytical measurements.
2.2 Experimental
The method involved in this study was extraction, saponification, separation, identification, and quantification.
2.2.1 Isolation of Oleoresin- Extraction:
The raw sample- marigold flower was provided by Synthite Industrial chemicals Ltd, Kolenchery, Kerala, where the
experimental part have been carried out. The experiment was carried out with two set of flowers (A1 & A2) - one stored
without preservation and the other with proper preservation technique. For processing, the full-blown marigold
flowers having minimum calyx portion are taken and was then laden in a room. It was then compressed and sprayed
with lactic bacterial culture, covered with a layer of lime and covered with black tarpaulin. This will induce lactic acid
fermentation under anaerobic condition. Under this condition, the material can be stored for 3 to 4 months. By this
technique, it was reported that xanthophylls are stabilized and preserved. The water from the raw material was removed
and then dried in a drier for 8 to 10 hour under controlled conditions at a temperature lower than 60- 65oC to a moisture
level of 8% to 10%. The dried flowers are powdered to a particle size of 0.5 mm and then extracted. Of the solvents,
hexane, acetone, ether, isopropyl ether, methylenechloride, 1, 2- dichloroethane, chloroform, hexane- acetone and
hexane- acetone-toluene; hexane was found to be the efficient solvent (Verghese.J 1998b) for better yield of
xanthophylls. The powdered marigold flowers were then packed in a column and were eluted using analytical grade
hexane under mild conditions (30°C, for 15 min). The extract (miscella) so obtained was distilled, under controlled
conditions until the desired quantity of the solvent in the oleoresin was achieved. In order to prevent the degradation of
xanthophylls, 0.1 to 0.3 % of ethoxyquin was mixed to the final product with stirring at a temperature less than 45oC.
2.2.2 Saponification
Most carotenoids including xanthophyll are stable under alkaline treatments; thus, the use of methanolic solutions of
potassium hydroxide is a common method of saponification, which de-esterifies the pigment to free xanthophylls,
sometimes at room temperature or by heating. Saponification was accomplished with 40% methanolic KOH by 20
minute treatment at 56oC. Enhanced stability of xanthophylls was obtained when the esters are partially saponified, then
Vol. 3, No. 2 Modern Applied Science
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neutralized with weak acid - acetic acid, propionic or lauric acid etc, so that the final product with pH greater than 8
contains about 10 to 20% by weight of unsaponified original xanthophylls esters. Oleoresins initially containing 12.5 %
xanthophylls esters saponified to 85% and 100%, after 75 days of storage at 40oC drops down to 5.2% and 33%
respectively (Verghese.J 1998b) and this result established the merit of selective, incomplete saponification in
conferring the stability. The alkali treated xanthophylls can be either incorporated to poultry feed itself or as the solution
of the concentrate in vegetable oil and other oils.
2.2.3 Separation
Separation methods can be classified as non-chromatographic and chromatographic. Non-chromatographic method uses
mainly phase partition, by using petroleum ether and aqueous methanol (90%) or ethylene dichloride (EDC) and
chromatographic methods adsorbents used are sucrose, silica gel etc. The product obtained after extraction was then
washed with EDC. The solvent was removed and dried.
2.2.4 Characterization
The most important technique in xanthophylls (carotenoid) analyses is UV-visible spectroscopy, which gives
information about the presence of rings, carbonyl groups, and isomeric effects. In this analysis, absorption maxima,
form, and fine structure of spectra are characteristic of the molecule’s chromophore. The purity of compounds is
obtained with a diode array detector (DAD), which makes the HPLC a versatile technique due to greater sensitivity,
resolution, reproducibility, speed of analysis and flexibility to use at inert conditions.
2.3 Analysis of pigment
The oleoresin was analyzed by AOAC method to determine the total xanthophylls concentration and by HPLC-
high-performance liquid chromatography (Hellish, 1990) to determine the profiles of the main components (Dietmar
2005). The xanthophyll esters obtained are unstable and are stabilized by saponification, which also resulted in the
boosting of xanthophylls content. About 0.05g of oleoresin was transferred into a 100 ml amber colored volumetric
flask and added 30 ml extractant (Hexane, 10 ml + Acetone, 7ml+ Absolute alcohol, 6ml + Toluene, 7ml). 2ml, 40%
methanolic KOH was added and shaken for a minute. The flask was then kept in a water bath (56oC) for 20 minutes.
Cooled and kept in the dark for an hour. Added 30 ml of hexane, shaken for 1 minute and was then diluted with 10%
Na2SO4 and kept in dark for an hour. The upper phase was 50 ml and with this part absorbance and chromatographic
analysis were carried out.
2.3.1 Spectrophotometric method
0.5 ml of the upper phase was transferred into a 50 ml flask and made up to mark with hexane. Absorbance was
measured at 474nm using hexane as reference.
Total xanthophylls = (A474 D) / (W 236); Where
A474 = absorbance at 474nm
D = Dilution factor
W = sample weight
236 = specific absorbtivity of Trans- lutein (g/L)
2.3.2 Chromatographic separation-HPLC
Aliquots of the Tagetes extract obtained from the hexane extraction were isocratically separated using HPLC, over a
C18 column in a normal mode. The colored fraction was separated using a mobile phase of a mixture of hexane and
ethyl acetate (65:35). About 1 ml of the upper layer was diluted with hexane and 20 μL of it was injected to the column
and was eluted at 1.0 ml/ min at room temperature. The pigments were monitored at 447 nm. The components profile
was obtained using the relative percentage of HPLC chromatogram area.
3. Results and discussion
Both saponified and unsaponified extracts of marigold were analyzed and from the chromatogram it was observed that
in both cases, the main component of oleoresin was Trans-Lutein. Saponification converts Xanthophyll esters to its free
form and more peaks are found in the chromatogram of saponified product. Chromatogram peaks were identified by
comparison to the retention time of standards and the peaks obtained were analogous to Cryptoxanthin, Cis-Lutein,
Trans-Lutein, Trans-Zeaxanthin and some epoxides (Figure: 6, 7).
If the flowers are not properly stored and preserved or else are of poor quality, then assay show a low xanthophyll
content. In the first run of the experiment, carried out using an unpreserved flower sample (A1), the yield and
xanthophylls content was 4.62% and 54.87 g/Kg respectively. Higher value was observed when the experiment was
repeated with well preserved (sample-A2) flowers (Table: 2). Xanthophyll isolation by solvent extraction method in
contradictory to the new studies (enzyme based flower preservation, solid state fermentation etc) showed a less efficient
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result due to the high temperature involved in isolation step and degradation of the component. The extracted oleoresin
was enriched from 105.19 g/Kg Xanthophyll content to 226.88 g/Kg Xanthophyll content, by saponification and
subsequent extraction with ethylene dichloride.
Although marigold flower is a cheaper source as a starting material for the isolation of lutein, its storage in seasonal
times is very important. From the present work, it was found that, the sample without proper preservation had a
diminution in the xanthophylls deduce the implication of preservation technique. A suitable technique for storage
enhances the stability of the pigment in the flower and hence an exhaustive study in this area is required. This study
involved an anaerobic and lactic acid treatment for the preservation of marigold flowers. Xanthophyll can retain some
of the solvent from which they are isolated and purified. The solvents can be easily removed by drying the oleoresin at
higher temperature, but in some instances the solvent hardly escapes from it. The traces of toxic organic solvents in the
oleoresin makes it unfit for the human consumption as a food colorant. Still another disadvantage of this solvent
extraction process is the hazardous organic wastes that face disposal problem.
4. Conclusion
The toxicological effects of the synthetic dyes in the food industry gave way to a renewed interest in the isolation of
natural pigments. With the growing legislative restrictions on the use of synthetic colors, a reappraisal of natural plant
pigments is taking place with a view to use them as possible colorants in foods. With the application of new innovations,
natural pigments can become more cost effective, increase their competitiveness against certified dye, and dye products.
According to the Code of Federal Regulations, marigold oleoresin should pursue the prescribed specification and only
purified lutein can be used in food applications for human consumption. The antioxidant property of the lutein crafts it
application even in making organic tea, which claims great medicinal value. Since large quantities of pesticides are used
in the cultivation of marigold flower, the toxic components may be present in the marigold oleoresin. With the more
studies of marigold extracts, showing its safety and non-toxicity, marigold flowers can be good source of natural orange
colorant in food applications. Advanced biotechnology can improve the novel varieties of marigold having higher
Lutein content to elevate Xanthophyll yield. As a food colorant, toxicity determination is valuable and hence the
evaluation of solvents used and the study of toxicants in oleoresin are being in the experimental stage. The
quantification of some of the toxicants-pesticides and trace metals, in the marigold flower and its oleoresin is also under
study to scrutinize the use of marigold oleoresin as a natural food colorant without any impairment.
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Table 1. Composition of lutein fatty acid esters (%)
(Ref: Sowbhagya et al. 2004)
Xanthophyll Type Gau et al Helrich
et al
Dipalmitate 35.5 37.57
Dimyristate 12.6 11.57
Myristate -
palmitate
24.7 24.23
Palmitate-stearate 14.4 15.55
Di-stearate 2.4 3.63
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Table 2. Comparative results of sample A1 and A2
(Xt – Xanthophyll content)
Sample Moisture
of flower
(%)
Oleoresin
Yield
(%)
Xt
(g/Kg) T-Lutein in
Xanthophyll
(%)
A1 10.0 4.62 54.87 36.62
A2 12.1 9.12 105.19 70.28
Vol. 3, No. 2 Modern Applied Science
26
Modern Applied Science February, 2009
27
Vol. 3, No. 2 Modern Applied Science
28
... Further, the dried powder was extracted with hexane to obtain oleoresin. In a different study, marigold flowers were physically pre-treated by grinding with anhydrous Na 2 SO 4 before extraction in hexane (Pratheesh et al. 2009). ...
... The purification methods can be classified as non-chromatographic and chromatographic. Phase partition is primarily employed in non-chromatographic methods by employing petroleum ether and 90% aqueous methanol or ethylene dichloride (EDC), while sucrose, silica gel, and other adsorbents are used in chromatographic methods (Pratheesh et al. 2009). Free lutein is frequently purified using crystallization, but this method has a relatively poor yield and purity. ...
Article
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In our comprehensive review, we delve into the critical steps of isolation of lutein and zeaxanthin from marigold flowers focusing on several pre-treatment technologies for marigold flower hydrolysis, non-green and green solvent-based extraction techniques of hydrolyzed solid biomass, and saponification of oleoresin while addressing the associated challenges and limitations. The review highlights the varying effects of different pre-treatments on the degradation of pectin, lignin, cellulose, and hemicellulose as well as on lutein and zeaxanthin ester yield. Notably, the enzymatic pre-treatment emerges as the most efficacious approach, despite its reliance on costly commercial enzymes. Based on the literature review, it is determined that supercritical fluid extraction, combined with ultrasound and various co-solvents gives off better yields of lutein as compared to the other extraction methods. This review also covers the saponification, purification, and recovery process. The applications of marigold flowers and lutein are also summarized.
... Chemically, TE is rich in flavonoids, phenolic metabolites, terpenoids, hydrocarbons, and carotenoids like lutein, among others (Table 1), which play a crucial role in the plant's protective adaptations and can serve as an argument to justify medicinal applications. The concentration of these bioactive metabolites positions TE as an important topic in pharmacological studies, highlighting TE as a rich source of lutein 15 (for more details about the discovery and historical development of lutein, see Section A2.), justifying its current use in treating various diseases and emphasizing the chemical basis for its pharmacological effects and therapeutic efficacy of its chemical extracts. Flavonoids and phenolics, like syringic and gallic acids, offer health protection through more non-specific antioxidant and anti-inflammatory effects. ...
Article
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The medicinal value of herbal products is often rooted in their “traditional” use, recontextualized by modern biomedical research granting them certain medical uses. Tagetes erecta L. (Asteraceae), native to Mexico, exemplifies such historical developments of a species that played a key role in developing a major pharmacologically active compound – lutein. T. erecta (Cempasúchil in Nahuatl) has held ritual and medicinal importance in Mesoamerica and was associated with the rain god Tláloc. The species’ historical use spans ancient texts with varied medicinal applications, including treating cold-related ailments and promoting menstruation and urination. However, the Spanish conquest redefined it culturally, medicinally, and religiously, mainly as an ornamental flower. The discovery of lutein in T. erecta marked a significant shift, emphasizing its role in macular health and preventing aging-related macular degeneration. Clinically, lutein trials reveal cognitive, visual, cardiovascular, and systemic health enhancements, substantiating its potential therapeutic benefits. Pharmacologically, it demonstrates significant anti-inflammatory, antiparasitic, and anticancer properties. Today, T. erecta is recognized globally for its rich carotenoid content. This multifunctional metabolite is also used in poultry feed and health supplements. In contemporary culture, cempasúchil, also known as the “flower of the dead,” has been adapted for ornamental, medicinal, ceremonial, and industrial uses. However, its traditional medicinal uses in pre-Conquest Mexico remain largely unexplored, with its current applications influenced by global research. T. erecta's evolution beyond traditional medical and ritual uses in Mesoamerica demonstrates the dynamic development of a medicinal plant's role in medicine, as well as a range of other spheres of daily life.
... The total xanthophyll content of the marigold extract was quantified by HPLC and expressed in terms of lutein equivalence considering that the chromophore properties of the carotenoid molecules remained unchanged by esterification [49]. An average xanthophyll content of 9-11 mg g −1 was reported in marigold flower extracts, subjected to variation due to varieties and cultivars [50]. In the present study, standard lutein was eluted at R t 6.7 min as a sharp peak with λ max of 446 nm ( Fig. 2A). ...
Article
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Optimization of the extraction process for natural compounds aims to obtain the maximum feasible yield quickly using the least amount of solvent. A single-step ultrasonic probe-assisted extraction (UPE) technique was observed to be superior compared to the exhaustive conventional and ultrasonic bath extraction for xanthophyll pigments from a hybrid genotype (DAMH-39) of African marigold (Tagetes erecta L.) in terms of less time and solvent requirement. The process variables of the UPE technique were optimized using a Box-Behnken design (BBD) of response surface methodology (RSM) followed by fine-tuning of the model using an artificial intelligence-based genetic algorithm (GA) for the maximum output of the response variable, i.e., the total xanthophyll yield. The GA-coupled RSM model predicted the optimum values of the process variables as 31.38 mL g⁻¹ solvent-to-solid ratio, 56.56% ultrasonication amplitude, and 30 min of ultrasonication time for a maximum xanthophyll yield of 13.35 mg g⁻¹, which was very close to the result of validation experiment (13.10 mg g⁻¹) with a calculated error value of only 1.88%. The quality of the extracted xanthophylls by the hybrid model-optimized method was found to be superior as compared to the exhaustive techniques. However, no significant differences were observed in the antioxidant activities of the extracts obtained by different extraction techniques due to the possible interferences from the co-extractives. Analysis of the chemical constituents of the xanthophyll extract confirmed the presence of lutein linoleate, an unsaturated fatty ester of lutein for the first time in marigold along with five monoesters and three diesters of lutein, and two diesters of violaxanthin. The study signified the potential of the RSM-GA hybrid model for process optimization of extraction of natural compounds.
... Similar to the current findings, they observed Tagetes erecta FRAP values between 329.4 and 609.2 µmol Trolox/g and 94.3% DPPH radical scavenging activity [32]. Moreover, antioxidant activity in Tagetes erecta was also found by Munira [33] and Pratheesh et al. [34]. ...
Article
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Marigolds (Tagetes spp.) are major sources of bioactive compounds. The flowers are used to treat a variety of illnesses and have both antioxidant and antidiabetic effects. However, marigolds exhibit a wide range of genetic variations. Because of this, both the bioactive compounds and biological activities of the plants differ between cultivars. In the present study, nine marigold cultivars grown in Thailand were evaluated for their bioactive compound content, as well as for their antioxidant and antidiabetic activities, using spectrophotometric methods. The results showed that the Sara Orange cultivar possessed the highest total carotenoid content (431.63 mg/100 g). However, Nata 001 (NT1) had the highest amount of total phenolic compounds (161.17 mg GAE/g), flavonoids (20.05 mg QE/g), and lutein (7.83 mg/g), respectively. NT1 exhibited strong activities against the DPPH radical and ABTS radical cation, and had the highest FRAP value as well. Moreover, NT1 demonstrated the most significant (p < 0.05) α-amylase and α-glucosidase inhibitory effects (IC50 values of 2.57 and 3.12 mg/mL, respectively). The nine marigold cultivars had reasonable correlations between lutein content and the capacity to inhibit α-amylase and α-glucosidase activities. Hence, NT1 may be a good source of lutein; it may also be beneficial in both functional food production and medical applications.
... The pigments area allowed to extract for three hours during a hot extractor at room temperature. Then, estimation of lutein pigment yield analyzed using spectrometer with obtained marigold oleoresin [14]. Measurement of color was done using UV-visible spectrophotometer for the estimation of lutein pigment present in the sample [15,16]. ...
Conference Paper
In recent years, huge attention has been focused to replacing the conventional petrochemical solvents by green solvents i.e. deep eutectic solvents (DES). The main goal of this work is to eliminate the toxic and volatile solvents like hexane in the extraction process. Hexane is usually used for extraction, where the extract of final product may carry traces of organic solvent. DESs are eco-friendly solvents for the extraction of plant pigments when compared to petrochemical solvents like hexane. Deep eutectic solvents (DES) considered as an alternative green approach as it maintains ionic liquids merits on tunability, sustainable character and also overcomes the ionic liquids by its shortcomings. The 30-40% production of marigold flowers are wasted and dumped into waterbodies, which can be utilized in various ways and can get wealth out of it, by producing natural dye, Vitamin tablets, capsules from its petals which consists of flavonoid lutein and carotenoid-lutein. The present study focuses on extraction of plant metabolites (Lutein) through green methods, using Marigold is a source to extract Lutein. Different combination of DES used in the lutein extraction are choline chloride+ glucose (ChCl+glucose), choline chloride+glycerol (ChCl+glycerol), and choline chloride+ethanol (ChCl+ethanol) and were compared with commercial solvents (ethyl acetate and hexane). The combination of ChCl+glucose gives the highest yield of lutein oleoresin as 368.64 g/kg, which is higher than the conventional solvents. The analysis of lutein using HPLC have resulted in the highest area percent of lutein was 79.87%, at 474nm in the combination of ChCl+glucose. Results indicated that DES is a more viable and environment-friendly solvent for extraction of pigments from Targetus erecta.L. The present study focuses on extraction of plant metabolites (lutein) through deep eutectic solvents.
... Another approach also ground the obtained marigold flowers and sieved them for particle size determination, and the minimum heating of ground sample was ensured, and moisture content was determined [40]. The extraction of lutein ester from marigold flowers was achieved by drying petals and grinding them with anhydrous Na 2 SO 4 before extracting with hexane [41]. Abdel-Aal and Rabalski [27] used seven cultivars of marigold flowers from the Tagetes erecta and patula families, including durango red, hero bee marigold souci, antigua orange, antigua yellow, safari scarlet marigold souci, safari yellow marigold souci, and janie primrose marigold souci. ...
Article
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The municipal authorities in developing nations face serious challenges in marigold flower garbage management. The primary issue is that they never are reused after prayers. Flower waste of Tagetes erecta, T. patula, and Calendula officinalis L. are commonly used for carotenoid and flavonoid extractions and, subsequently, used for incense stick and biogas production. Marigold plants are also used for phytoremediation during their growth stage. The lutein industry is booming due to its increasing market demand, expected to reach ~2121.2 billion tons by 2022, where marigolds are a major contributor globally. The process of isolating lutein from saponified marigold oleoresin yields a product with 70–85% purity. Lutein is a major xanthophyll (70–88%) of marigold petals, and a maximum of 21.23 mg/g of lutein was extracted. This review discusses the properties of selective marigold species, their compositions, and the extraction of different flavonoids and carotenoids, especially lutein. Moreover, different extraction methods of marigold lutein, the collection of marigold waste, and their subsequent utilization to derive several value-added products are discussed. Among physical treatments, ultrasonic-assisted extraction and enzymatic treatment with 5% solids loading were the maximum-yielding methods.
... W ell-preserved flowers exhibit a high yield of xanthophyll content in contrast to the unpreserved flower. The stability and amount of xanthophylls extraction increases on saponification and subsequent purification with Ethylene Dichloride (Pratheesh et al., 2009). Pretreatment of marigold flowers with sodium hydroxide citric acid followed by hydraulic pressing results in higher pigment yield (Sowbhagya et al., 2013). ...
Article
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Marigold (Tagetes spp.) is one of the most popular flower crop commercially exploited for multipurpose use. Apart from great demand of marigold flowers, the plants use in phytoremediation and allelopathic effect has been greatly exploited. Marigolds can be used against plant parasitic nematodes as a cover crop in rotation, as an intercrop, or as a crop residue amendment. Successful use of marigold as trap crop is well on record whereas its use as potential natural herbicide needs to be explored. Essential oils obtained from marigold possess antibacterial and antifungal properties and are widely used in perfumery industries, as insect repellent and as flavor component. Its extracts can be explored as alternative natural insecticides towards the stored products. Use of marigold for its medicinal value for curing various diseases has been well documented. Carotenoids extracted from flowers are being used commercially in pharmaceuticals. Marigold extract also finds application in coloring foods and various dairy products. Marigold petals are used as additives for poultry feed, as they provide bright colors in egg yolks, skin and fatty tissues and also as emulsifying gum. Silver and gold nanoparticles have been synthesized from marigold for antimicrobial activity. This review paper discusses the research undertaken for various uses of marigold plant worldwide.
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Abstract: The primary causes of environmental degradation in a country could be attributed to the rapid growthof population, over-use of ecological resources, and establishment of different multinational companies andindustries, which majorly affects the natural resources of the environment. Floral waste generated can become athreat to the environment and human beings. The rapid increase in the volume of waste is one of the significantphenomena leading to an environmental crisis. The main options available for processing/treatment or disposalof solid waste are composting, vermicomposting, anaerobic digestion, bio methanation, incineration, gasification,production of refuse-derived fuel, etc. There is a modern approach for converting floral wastes into value-addedproducts namely compost, food products, biosurfactant production, incense sticks, etc. The present study dealswith managing temple floral waste through efficient extraction of phytobiotic compounds developed duringensilage fermentation. Evaluation of the phytobiotic compounds using gas chromatography-mass spectrometry(GC-MS) was done. Around 30 compounds with a retention time of 2.02min to 35.072min were identified inGC-MS. More than 10% of these compounds are Neophytadiene 43.88%, 9,12,15-Octadecatrienoic acid-methylester 13.45% and hexadecanoic acid-methyl ester 13.24%
Article
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Aztec marigold oleoresin-in-water (O/W) emulsions were formulated with mesquite gum or gum arabic and their blends as emulsifying and protective agents, at pH values of 3, 5 and 7. Changes in the emulsions average particle size were determined by laser ray diffraction, in tinctorial power by visible spectrophotometry and in color by reflectance measurements. Both gums and their blends form highly stable O/W emulsions against drop coalescence and color loss. The emulsifying agent composition and pH have an important role in determining the degree of effectiveness of the emulsions against color loss and drop coalescence kinetics. Mesquite gum provided a better stability against drop coalescence than gum arabic, and furthermore their blends had a synergistic effect providing a higher stability
Article
Four- to 10-fold improvement of colour uniformity and minor changes of colour yield have been found upon dyeing Nylon 66 and microfiber Nylon 6 fabrics in the presence of cyclodextrin compared to dyeing without it. 1H NMR data supported the role of cyclodextrin as dye complexing agent. Product quality, however, was also dependent on fabric nature, since for conventional Nylon 6, color uniformity was not improved by the presence of cyclodextrin systems.
Article
This study on anthocyanin colour variation (intensity, lambda(max), epsilon) over the pH range 1-9 during 60 days of storage, was conducted on petunidin 3-[6-O-(4-O-E-p-coumaroyl-O-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside]-5-O-beta-D-glucopyranoside (petanin) and cyanidin 3-O-beta-D-glucopyranoside (cy3glc) at 10 and 23 degrees C. Compared to cy3glc, petanin afforded higher colour intensity and higher or similar stability throughout the whole pH range. At pH 4.0, 84% of petanin was intact after 60 days storage at 10 degrees C, while the corresponding solution of cy3glc was totally degraded. At pH 8.1 the colour intensity of petanin was even higher than at the lowest pH values. The visible lambda(max) absorption of petanin after 5 days at pH 8.1 at 10 degrees C was similar or higher than the corresponding absorptions of the fresh solutions of cy3glc at any pH. The use of anthocyanins like petanin as food colorants in slightly alkaline products (bakery, milk, egg, etc.) should therefore be considered-at least in products with limited storage time kept in a refrigerator. (C) 1998 Elsevier Science Ltd. All rights reserved.
Article
Reversed-phase C30 HPLC was applied to study the identity of lutein isomers and to monitor the effects of solids content and elimination of water-soluble substances on the isomeric carotenoid profiles of marigold (Tagetes erecta) samples treated with enzymes. The tentative identity of four lutein isomers present in saponified marigold extracts was confirmed. Enzymatic treatment on a 5% solids slurry produced the marigold meal with the highest all-trans-lutein content [25.1 g/kg dry weight (dw)]. We did not observe variations in the distribution in percentage of lutein isomers due to enzymatic treatment; the elimination of water solubles had a significant but small effect on such variations. The solids content was the principal factor that affected the carotenoid profiles. An analysis of the distribution showed that 15% solids gave the highest all-trans-lutein percentage in treated meals. Interestingly, with 20% solids both the degradation of lutein and the percentage of all-trans-zeaxanthin were the highest. Keywords: Lutein; carotenoids; pigments; marigold; Tagetes
Article
ABSTRACTA novel quantitative procedure for the analysis of lutein esters in Marigold flowers (Tageres erecta) using high performance liquid chromatography is described. A new solvent system consisting of methanol and ethyl acetate suitable for the separation of carotenoid hydrocarbons and esters on reversed phase adsorbent was developed for the analysis. Lutein ester concentrations in fresh Marigold flowers varied from 4 pg/g in greenish yellow flowers to 800 pg/g in orange brown flowers. The method is suitable as a general procedure for carotenoid analysis in fruits and flowers where the hydroxylated carotenoids are acylated.
Article
The rate of betanine degradation as affected by monocarboxylic acids (lactic acid, acetic acid), metal cations (Fe+++, Cu++), antioxidants (ascorbic acid, -tocopherol) and sequestrants (citric acid, Na2 EDTA) was studied. Betanine was extracted from beets using water, and purified by molecular exclusion and adsorption chromatography. Column packings used were Sephadex G-25, polyacrylamide, and polyvinylpolypyrrolidone. The effect of food additives on the rate of oxidation of betanine in buffered systems was determined using a modification of the active oxygen method. A betanine solution was placed in a reaction chamber, held at 75° C, and oxygen was passed through the solution at a rate of 3 ml/min. The half-life value of betanine at 75° C, pH 5.0 in a phosphate buffer was 48.0 ± 1.0 min (control). Addition of 100 ppm lactic acid had no effect on stability (41 ± 1.7 mm), while 5.9% acetic acid caused a decrease in stability (33.4 ± 1.9 min) possibly as a result of pH changes at elevated temperatures. Metal ions at a level of 100 ppm caused an increase in the degradation rate compared to that of the control with addition of iron resulting in a half-life value of 33 ± 1.4 min. Copper had the greatest effect, reducing the half-life value to 6.0 ± 0.2 mm. Neither 100 ppm ascorbic acid nor 100 ppm a-tocopherol affected the half-life value of betanine (45.3 ± 2.3 and 50.2 ± 3.4 min, respectively). Ascorbic acid at 1000 ppm decreased the halt-life value (32.3 ± 3.3 min), whereas 10,000 ppm citric acid and 10,000 ppm EDTA caused an increase in the half-life value of 1.5 times compared to that of the control (69.4 ± 3.1 and 70.7 ± 7.1 min). Both 100 and 1000 ppm citric acid had no effect on betanine stability.
Article
Effects of a wide variety of antioxidants and related compounds on the stability of betanine were measured in air-saturated solutions at 40°C pH 5.0. No phenolic or sulfur-containing antioxidant was effective in stabilizing the pigment. Ascorbic and isoascorbic acids had similar effects in improving betanine stability in a citrate buffer. When citric acid was combined with ascorbic acid, the antioxidant effect was no greater than when ascorbic acid was used alone.
Article
Lutein and zeaxanthin, two xanthophylls supposed to delay formation of age-related macular degeneration (AMD), are found in numerous new dietary supplements appearing on the international market. Usually, the lutein concentration ranges from 0.25 to 20mg/serving size. The lutein contents of 14 products with lutein highlighted on the label were evaluated. Oily formulations were dissolved, and powdery capsule contents were extracted with solvents before high-performance liquid chromatography (HPLC) analysis (diode-array detector, 450nm) using a C30 column. If lutein diesters from marigold (Tagetes erecta) were present, the extracts were saponified with methanolic KOH. To unequivocally identify carotenoids, HPLC-(atmospheric pressure chemical ionization)mass spectrometry was applied. In this study only all-trans-lutein was quantified, whereas cis isomers (approximately 1–5 area% of total lutein) were not taken into account. The lutein concentration of half of the products investigated was found to be below the amount stated, varying here from 11 to 93%. With the exception of one product, all dietary supplements contained zeaxanthin in amounts typical for the use of marigold oleoresin (6.01.4 area% of all-trans-lutein). The high discrepancy found between the amounts labeled and determined in half of the products may be attributed to degradation reactions or to improper storage conditions.
Article
The hybrid-race silk yarn was dyed till equilibrium with natural lac dye (laccaic acid) and the thermodynamics of dyeing were investigated. The adsorption isotherm obtained was identified to be a Langmuir type. When the temperature increased, the partition ratio and the standard affinity decreased drastically. The values of heat of dyeing and entropy of dyeing were−13.20 kcal/mol and-0.03 kcal/mol/K, respectively. The effect of memecylon used as a mordant on silk dyeing with lac dye was also studied. It revealed that using memecylon promoted the adsorption of laccaic acid on silk and increased the attraction between laccaic acid and silk surfaces.
Article
By means of reversed-phase high-performance liquid chromatography in the system acetonitrile-dichloromethane, the xanthophyll fatty acid esters from a purified extract of marigold flower petals (Tagetes erecta) were isolated on a semipreparative scale. The structures of the xanthophyll fatty acid esters were elucidated by mass spectrometry. The presence of the hitherto unknown mixed esters xanthophyll palmitate stearate and xanthophyll palmitate myristate was demonstrated, in addition to the major component xanthophyll dipalmitate. The latter was isolated in larger quantities from the xanthophyll fatty acid ester mixture by Craig counter-current distribution.