|Title of Invention||
AN IMPROVED PROCESS FOR THE EXTRACTION OF CARTHAMIN DYE FROM SAFFLOWER (CARTHAMUS TINCTORIUS)
|Abstract||An improved process for the extraction of carthamin dye from safflower Carthamus tinctorius with polar solvents in a ratio 1:5 adjusting pH of extract between 4-5 by known method, concentrating the extract in vacuo at a o temperature in the range of 60-70 C, washing the above extract with non-polar solvent, concentrating the washed extract, preserving concentrated extract containing carthamin dye in a sterlized sealed container.|
|Full Text||The present invention relates to an improved process for the extraction of carthanin dye from safflower (Carthaaus tinctorius).
Natural colours have always formed part of roan's normal diet and have therefore. been safely consumed for countless generations. Flavonoids and related compounds provide the largest group of plant dyes ranging in colours from the pale yellow (isoflavones) through deep yellow (flavones, flavonols, chalkones and aurones), orange (aurones) to red and blue (anthocyanins). The flavonoids and chalkones provide a comprehensive range of attractive colours and they occur widely in fruits and vegetables. Carthamin is the only chalkone-type pigment suggested for colouring foods. It has a great future and finds use of colouring cakes, buscuits and icecream (Natural Food colorants, eds. G.A.F. Hendry and J.D. Houghton, Blackie and Son Ltd, Glasgow and London, 1992, pp 258). When used in large quantities for making edibles, it acts as cathartic. Both a red and a yellow colorant can be obtained from safflower for use in pine apple juice and yoghurts (Umeda, A. and Inoue, K., Japan Patent No. 70040266, 1970). Flavonoidal colorants are mostly obtained from Tarfetes. Artocarpus. Butea. Mallotus and Myrica. Their applications could be enhanced, however, with new sources and stable colour variants, modification of currently existing processes and technological advances that would make purer and more stable preparations available.
Food colorants extracted from natural sources are exempted from rigorous and costly toxicological testing that synthetic dyes must undergo prior to their clearance as safe food ingredients; natural colours are generally considered safe due to their presence in edible plant material. The use of flavonoids and chalkone dye is restricted because of their unstability and unavailability as low cost natural sources. Banning of several red dyes (Meggos, H.N., Food Techno1. 38, 70-74, 1984) has encouraged their isolation and purification from natural sources. Here, we are reporting the process technology for the extraction of chalkone dye from an Indian source of safflower t Carthamus tinctorius. Its temperature and pH were maintained such that the colour was stable even after a long period at room temperature.
Carthamin, sometimes called carthemone, is a yellow to red preparation extracted from the flowers of Cartharous tinctorius. It contains three chalkones, the red carthamin, safflor yellow A and safflor yellow B (An, X. et al. Zhongcaoyao 21, 188, 1990). Fresh yellow petals contain precarthamin, which oxidises to form the red colorant carthamin.
The dye is reported to be fugitive to light and air, and sensitive towards alkali. It is a week dye. Carthamin is sparingly soluble in water but can be extracted with sodium carbonate, precipitated with dilute acid and used directly.
The extraction of carthamin dye generally involved the use of acidic solvents. The traditional and most common method of carthamin extraction involve maceration or soaking of flowers with acidulated water which removes yellow colouring matter. The residue is extracted with sodium carbonate solution and precipitated with dil acids. Purification and stabilization has been greatly enhanced by adsorption of carthamin on cellulose. Apparently cellulose has great affinity for carthamin and it is so strong that carthamin can be retained for more than 1000 years without appreciable change in red coloration (Saito, K. and Fukushima, A., Food Chem. 29, 161, 1988).
In another method tissue culture technique was used. The flower bud cells were cultured on Murashige and Skoogs media followed by liquid culture on cellulose. (Yamo et al. Japan Patent no. 63 253 386, 1987). An improved method involved liquid culture using 4% cellulose (Daimon et al., Japan Patent No. 0120 092, 1989).
In the reported methods, use of mineral acids may alter the native form of carthamin dye. The production of the dye using tissue culture technique will increase the cost.
The main objective of the present invention is to provide an improved process for the extraction of carthamin dye from safflower. Another object of the present invention is to provide a quick, efficient and economical process, better than earlier reported for the extraction of carthamin dye from Carthamus tinctorius.
Capthamus tinctorius. widely cultivated in India, is collected from Bhagalpur, Bihar. The non toxic and cheap solvents such as water and ethanol are used for the extraction of dye. The extract thus obtained was stabilized using a natural edible fruit juice to store the dye for a long period. The procedure is simple and cheap than reported methods and provided an stable carthamin dye to be used as natural food colorant.
Accordingly the present invention provides an improved process for the extraction of carthamin dye which comprises extracting of Carthamus tinctorius flower petals with polar solvents, adjusting pH of extract between 4-5 by known method, concentrating the extract in vacuo at a temperature in the range of 60-70*, washing the above extract with non-polar solvent, concentrating the washed extract and preserving concentrated extract containing carthamin dye in a sterlized sealed container if disired.
In an embodiment of the invention the part of the flowers used for the extraction of carthamin dye may be such as petals.
In another embodiment of the invention the polar solvents used for the extraction may be such as water, ethyl alcohol, methyl alcohol, propyl alcohol and mixtures there of.
In yet another embodiment of the invention pH of the extract may be adjusted by using citric acid, tartaric acid, oxalic acid, lemon juice and citrus juice.
The non-polar solvents used for washing may be such as n-hexane, petroleum ether, heptane and cyclohexane.
The following examples illustrate the process of the present invention. However, this should not be construed to limit the scope of the present invention.
Dried petals of safflower (1 kg) were made into small pieces by crushing with hands and extracted with water (51) followed by ethanol (51). The ethanol extract was washed with hexane (2 1) and the pH of the ethanol extract was made to 5 by using lemon juice. The volume of this extract was reduced to 50% by evaporating at 60-70* in vacuo. The extract was then cooled to room temperature and filtered. The
clear solution thus obtained was concentrated to 500 ml in vacuo. The concentrate thus obtained was stored in a sterlized sealed container. The stability in the colour was observed for a period of more than six months.
Example - II
Dried petals of safflower (500 g) were crushed into small pieces and extracted with water (2.5 1) followed by extraction with methanol (2.5 1). The volume of methanol extract was reduced to 500 ml at 70* and this extract was fractionated with n-hexane (500 ml), ethyl acetate (500 ml) and n-butanol (500 ml). The butanol extract containing the dye was concentrated to dryness In vacua. This method was lengthy, involving the use of toxic solvents such as methanol and butanol.
Example - III
Dry flower petals of safflower (500 g) were extracted with water (2.51) followed by extraction with 5% sodium bicarbonate solution. This extract was acidified with 5% citric acid to pH 4. The acidic extract -was filtered and concentrated to 500 ml in vacuo at 60-70 . This concentrate was fractionated with n-hexane (500 ml), chloroform (500 ml) and n-butanol (500 ml). This method was also lengthy and less economical involving use of toxic solvents.
Example - IV
Dry petals of safflower (500 g) were extracted with methanol (2.5 1). The extrct was concentrated to 500 ml and diluted with water (500 ml). The aquous methanolic concentrate was fractionated successively with n-hexane (500 ml), ethyl acetate (500 ml) and n-butanol (500 ml). The lengthy method again involves the use of toxic solvents.
The present invention has following advantages over the reported procedures.
This process is simple and no costly chemicals are required. The media used to stabilize the colour is from a natural edible source and easily acceptable. A bright and stable colour at room temperature was achieved. Moreover, the colour can be stored for a long period. Here, we have avoided the use of toxic chemicals and lengthy process of column chromatogrphy which has reduced overall extraction cost without effecting the nature of carthamin dye.
We clain :
An improved process for the extraction of carthamin dye which comprises extracting flower petals of Carthamua tinctorius with polar solvents, adjusting pH of extract between 4-5 by known method, concentrating the extract in vacuo at a temperature in the range of 60-70 , washing the above extract with non-polar solvent, concentrating the washed extract, preserving concentrated extract containing carthamin dye in a sterlized sealed container if desired.
An improved process as claimed in claim 1 wherein the solvent used for extraction is such as ethyl alcohol, methyl alcohol, water and mixture thereof.
An improved process as claimed in claims 1-2 wherein the pH is adjusted by acid such as citric acid, tartaric acid, oxalic acid or lemon juice and citrus juice and mixture thereof.
An improved process for the extraction of carthamin dye from Carthamus t inctorius substantially as herein described with reference to the examples.
|Indian Patent Application Number||1102/DEL/1998|
|PG Journal Number||11/2008|
|Date of Filing||27-Apr-1998|
|Name of Patentee||COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH|
|Applicant Address||RAFI MARG, NEW DELHI-110001|
|PCT International Classification Number||C09B 23/00|
|PCT International Application Number||N/A|
|PCT International Filing date|