Title of Invention

A PROCESS FOR OBTAINING WATER DISPERSIBLE ASTAXANTHIN COMPOSITION

Abstract

The present invention relates to a process for obtaining water dispersible astaxanthin composition. Astaxanthin is a red ketocarotenoid from green alga Haematococcus pluvialis SAG 19-1a. Astaxanthin is extensively used in farmed salmon, trout and poultry as pigmentation source. However, in recent years its nutraceutical and pharmaceutical applications gained importance due to its high antioxidant activity. Astaxanthin in food grade solvent and edible matrix dissolved in aqueous solvent, were homogenized and evaporated to get water dispersible astaxanthin composition. This astaxanthin containing composition can be used as nutraceutical as well as colorant in the aqueous medium.

Full Text

Field of Invention The present invention relates to a process for the preparation of water dispersible astaxanthin composition. The composition produces red colour in aqueous medium. Background of invention and Description of Prior Art Astaxanthin is a ketocarotenoid (3,3'-dihydroxy ß ,ß carotene- 4, 4' dione) used extensively in farmed salmon, trout and poultry as pigmentation source. The green alga Haematococcus is one of the natural sources which accumulate astaxanthin upto 2-3% of dry biomass. The organism has gained commercial importance owing to its high content of astaxanthin. The interest in the human health application of astaxanthin is increasing as it has been approved by FDA as dietary supplement. Its high antioxidant activity implied many nutraceutical and pharmaceutical applications. The biological functions of astaxanthin include protection against oxidation of essential polyunsaturated fatty acids, protection against UV light effects, immune response, pigmentation. (Lorenz, R.T. and Cysewski, G.R., 2000. Commercial potential for Haematococcus microalgae as a natural source of astaxanthin. Trends in Biotechnology. 18,160-167). Like majority of carotenoids, astaxanthin is water-insoluble. Hence cannot be used as food colourant in aqueous medium and requires a chemical system to overcome the problem. Therefore the present invention was aimed at preparation of astaxanthin containing composition which could be used as nutraceutical as well as colourant in the aqueous medium. In the present invention astaxanthin is obtained from Haematococcus pluvialis SAG 19-1 a. The culture was obtained from Sammlung von Algenkulturen, Pflanzen Physiologisches Institut, Universitat Gbttingen, Gottingen, Germany. Astaxanthin constitutes 85-90% of total carotenoids in this organism. Procedures currently reported for preparation of water soluble carotenoid composition are as follows: Reference may be made to the method of Lockwood et al 2003 (Journal of Pharmaceutical Sciences, 92, 922-926; Improved Aqueous solubility of Crystalline astaxanthin by Captisol (Sulfobutyl Ether ß-cyclodextrin) wherein ß-cyclodextrin was used to increase the aqueous solubility of astaxanthin. The limitation in this method is that the solubility of astaxanthin is very low that it cannot be used as food colorant. Reference may be made to US patent 6132790 wherein carotenoid composition is reported. Carotenoid composition comprising a carotenoid in an oil solvent, dispersion of a water dispersible matrix and a stabilizer is reported. The limitation in this method is that the carotenoid emulsion is held at 75°C which is not suitable for heat labile carotenoids. Reference may be made to US patent 0169999 wherein process for production of water-dispersible formulation containing carotenoids is reported. The limitation in this method is that the carotenoid emulsion is treated at 130°C which is not suitable for heat labile carotenoids. Reference may be made to US patent 6261622 wherein water-dispersible carotenoid pigment preparation is reported. Water-dispersible carotenoid pigment preparation, prepared by blending the carotenoid pigment and the dispersion stability containing the soybean extract fiber as an ingredient is reported. The limitation in this method is that the preparation is a carotenoid-containing aqueous composition. Reference may be made to US patent 5364563 wherein powdered aqueous carotenoid dispersions is reported. It describes a process for producing a powdered carotenoid preparation comprising forming a suspension of a carotenoid in high boiling oil without the presence of an organic solvent. The suspension is superheated with steam for maximum period of thirty seconds to form a solution of carotenoid in oil. After that, solution is emulsified in an aqueous solution of a colloid and thereafter spraying and drying the emulsion, a powder is formed. The limitation in this method is that losses of carotenoids at high temperatures used during the treatment with superheated steam. Reference may be made to US patent 4726955 wherein process for the preparation of a finely divided, pulverulent carotenoid preparation is reported. It describes dissolving a carotenoid in a volatile, water-miscible, organic solvent at 50°C to 240°C, under atmospheric or super atmospheric pressure, in less than 10 seconds, immediately precipitating the carotenoid in colloidal disperse form from the resulting molecular disperse solution by rapidly mixing with an aqueous dispersion of a colloid at 0°C to 50°C and freeing the resulting dispersion from the solvent and the dispersing medium in a conventional manner. The limitation in this method is that the colour of the precipitated carotenoid colloidal disperse will differ considerably when compared to the original colour of the carotenoid. Reference may be made to US 0156871 wherein water-soluble compositions of bioactive lipophilic compounds is reported. It describes water-soluble composition, comprising a solubilizing agent. The limitation in this method is that the preparation includes antibiotics and solubilizing agents and it is meant for therapeutic purpose and not for food applications. Reference may be made to US 5811609 wherein process for the preparation of a water dispersible carotenoid preparation in powder form is reported. It describes preparation of a water dispersible carotenoid preparation in the form of discrete carotenoid microparticles comprising the steps of milling a carotenoid in an aqueous medium in the presence of a hydrocolloid to form a suspension, heating the suspension formed by the milling to a temperature sufficiently high to cause a total or partial melting of the carotenoid, subsequently cooling the suspension, and finely dividing and drying the suspension to form a powder. The limitation in this method is that the carotenoid emulsion is held at 150°C to 200°C which is not suitable for heat labile carotenoids. Reference may be made to US patent 5,968,251 wherein production of carotenoid preparations in the form of coldwater-dispersible powders, and the use of the novel carotenoid preparations is reported for synthetic carotenoids. It describes preparing a molecular-disperse solution of a carotenoid. The carotenoid results as nanodisperse phase in the aqueous phase. The limitation in this method is that the carotenoid emulsion is for synthetic carotenoids which exists mainly (75%) as trans forms while natural carotenoids exists as mixture of cis and trans forms. . Reference may be made to European patent 1455598 wherein carotenoid formulation is reported. It discloses the use of a lycopene coated with a water non-soluble thin film comprising amphiphilic protein polymer for coloring with red color, foods, pharmaceuticals or cosmetics. The limitation in this method is such a coated lycopene can used as an additive or colorant in foods, pharmaceuticals or cosmetic preparations having lipid contents higher than 5%. Reference may be made to US patent 5460823 wherein the process for preparing a water dispersible hydrophobic or aerophilic solid is described According to this, mixture of hydrophobic carotenoid solid powder and hydrocolloid suspension is stirred at a temperature between 0°C and 100°C to form first aqueous suspension. This aqueous suspension is transferred to a mill having cooling equipment and wet grinded at 0°C and 100°C to form second aqueous suspension. The second aqueous suspension is then spray dried to obtain dry powder. The limitation of this process is, it involves heating the carotenoid at high temperature which is undesirable for heat labile compositions. Reference may be made to US patent 6406735 wherein a process for preparing a finely divided pulverous carotenoid retinoid or natural colorant preparation is described. According to this, the carotenoid and water-immiscible solvent suspension is fed to heat exchanger. This suspension is then heated at 100-250°C to provide solution. Mixing this solution with aqueous solution comprising swellable colloids at a temperature in the range of 20-100°C. The suspension is mixed with steam and spray dried to convert into pulverous preparation. The limitation of this process is, it involves heating the carotenoid at high temperature which is undesirable for heat labile compositions. Reference may be made to US patent 6863914 wherein preparation of stable, aqueous dispersion and stable, water -dispersible dry powders of xanthophylls and production and use of the same has been described. According to this, xanthophylls is dissolved in water-miscible organic solvent or a mixture of water and a water-miscible organic solvent at temperature above 30°C. Mixing this solution with and aqueous solution of a protective colloid casein or caseinate. This has limited utility since casein or caseinate can not be used in a range of food formulations. The link www.aocs.org/member/division/fsff/ribeirohenelyta.pdf describes the procedure of the emulsification process. The suspension of carotenoid in miglyol is passed through heat exchanger at 140-210°C to form pre-emulsion. This pre-emulsion, under high pressure, passed through high pressure pump and microfluidizer resulting in fine emulsion. The limitation of this method is, it involves heating the carotenoid at high temperature which is undesirable for heat labile compositions. Objects of the Invention The main object of the present invention is thus to provide a process for obtaining water dispersible astaxanthin composition which obviates the drawbacks as detailed above. Another object is to provide a process that does not involve heating at high temperature which is undesirable for heat labile astaxanthin. Yet another object is to provide a process wherein food grade solvents can be used hence considered safe Summary of the Invention Accordingly, the present invention provides a process for the preparation of water dispersible astaxanthin composition which comprises: (a) dissolution of astaxanthin in known food grade solvent in a ratio of 1:0.5 to 1:1.2 to obtain astaxanthin solution; (b) simultaneously dissolving the edible matrix of the kind such as herein described in water in a ratio of 10:1 to 10:1.2 to obtain an aqueous matrix; (c) boiling the aqueous matrix as obtained in step [b] in the presence of stabilizing agents of the kind such as herein described; (d) homogenizing the astaxanthin solution as obtained in step [a] with hot aqueous solution of edible matrix as obtained in step [c]; (e) evaporating the solvent to get a solid; (f) drying the solid as obtained in step [e] at 40 to 50 degree C to obtain the desired water soluble astaxanthin composition. Detailed Description of the Invention The present invention relates to a process for the preparation of water dispersible astaxanthin composition. Astaxanthin is a ketocarotenoid which is known to have high antioxidant activity. Owing to this property its potential in nutraceutical and pharmaceutical applications is increasing. However its lipophilic property limits its application in food formulations of aqueous nature. Therefore the present invention focused on a process for water dispersible astaxanthin to increase its scope of application and to utilize its beneficial effects to a maximum extent. The invention involved preparation of astaxanthin extracted from encysted cells of Haematococcus pluvialis SAG 19-1 a in food grade organic solvents such as dichloromethane for solubilizing the astaxanthin followed by addition of edible matrix with stabilizer and homogenization of the mixture and evaporation of organic solvent followed by drying the mixture. The present invention provides a process for the preparation of water dispersible astaxanthin composition, wherein the process steps comprise: a) dissolving of astaxanthin obtained from Haematococcus cells in food grade organic solvent selected from acetone, dichloromethane, isobutyl acetate, n-butyl alcohol, heptane, iso-amyl alcohol in a ratio of 1 to 0.5 to 1.0 under nitrogen gas in dim light (to prevent oxidation of the compound due to exposure to light and air); b) Mixing of astaxanthin in organic solvent to edible matrix selected from edible starch, Maltodextrin, cyclodextrin dissolved in hot water in the concentration ratio of 10:1 to 12:1 at 40-60°C with stabilizer selected from gum acacia, ascorbic acid and citric acid in the concentration range of 0.5% to 2.0%; c) The viscous mixture thus obtained was homogenized with ultrasonic homogenizer for 5 sec. The solvent was evaporated by known vacuum distillation and the aqueous layer was dried at 45°C. The resulting dry composition can be used as astaxanthin water dispersible preparation (as food colorant) especially in jellies, fruit juices, milk shakes, dairy products etc. The preparation is found to be stable for long time at low temperatures. The water dispersible astaxanthin thus obtained consisted of astaxanthin in the concentration range of 6.1-7.5%, maltodextrin 84-86%, gum acacia 08-1.2%, ascorbic acidO.9-1.2%, citric acid 4.0-4.9%. In an embodiment of the present invention, the solvent for making carotenoid composition may be selected from acetone, dichloromethane, isobutyl acetate, n-butyl alcohol, heptane, iso-amyl alcohol. In another embodiment of the present invention the edible matrix may be selected from starch, dextrin, maltodextrin. p-cyclodextrin. In yet another embodiment of the present invention, the stabilizing agent incorporated at 0.5-2.0% level. In yet another embodiment of the present invention, evaporating the solvent by vacuum distillation. In still another embodiment of the present invention, the stabilizing agent is preferably gum acacia, ascorbic acid and citric acid. In yet another embodiment of the present invention, drying the water content at 40-50°C. The novelty of the invention is that the astaxanthin composition is easily dispersible in aqueous phase, therefore can be used as food colorant. Another advantage is that the process does not involve heating at high temperature which is undesirable for heat labile astaxanthin. Yet another advantage is that food grade solvents can be used for in the process hence considered safe. Yet another advantage is that the astaxanthin composition adds nutraceutical value to the food since astaxanthin has very high antioxidant activity. The following examples are given by way of illustration of the present invention and therefore should not be construed to limit the scope of the present invention. EXAMPLE-1 Astaxanthin extracted from Haematococcus pluvialis SAG 19-1 a cells was dispersed in dichloromethane in dark under nitrogen gas atmosphere. Soluble starch and gum acacia were dissolved in water and boiled starch suspension was mixed with carotenoid suspension. This viscous mixture was homogenised with ultrasonic homogenizer for 5 sec. The solvent was evaporated by vacuum distillation and the aqueous layer is dried at 45°C for 3 hours. The resulting dry composition consisted of 6.1% astaxanthin, 86.6% starch, 1.2% gum acacia, 1.2% ascorbic acid, 4.9% citric acid. EXAMPLE-2 Astaxanthin extracted from Haematococcus pluvialis SAG 19-1a cells was dispersed in Acetone in dark under nitrogen gas atmosphere. Maltodedextrin and gum acacia were dissolved in water and boiled starch suspension is mixed with carotenoid suspension. This viscous mixture was homogenised with ultrasonic homogenizer for 5 sec. The solvent was evaporated by vacuum distillation and the aqueous layer was dried at 50°C. The resulting dry composition consisted of 7.5% astaxanthin, 85.2% Maltodextrin, 1.2% gum acacia, 1.2% ascorbic acid, 4.9% citric acid. EXAMPLE-3 Astaxanthin extracted from Haematococcus pluvialis SAG 19-1 a cells was dispersed in dichloromethane in dark under nitrogen gas atmosphere. Maltodextrin and gum acacia were dissolved in water and boiled starch suspension was mixed with carotenoid suspension. This viscous mixture was homogenised with ultrasonic homogenizer for 5 sec. The solvent was evaporated by vacuum distillation and the aqueous layer was dried at 45°C. The resulting dry composition consisted of 6.1% astaxanthin, 86% maltodextrin, 1.2% gum acacia, 1.2% ascorbic acid, 4.9% citric acid. The obtained carotenoid composition was incorporated in a jelly preparation at 4ppm and 16ppm level. The L, a, b hunter colour value of the jelly was measured by colour measurement system. The 'a' value corresponding to redness was 2.8 and 12.5 in at 4 and 16ppm respectively. The 'a' value of control sample was found to be-1.05. The main advantages of the present invention are: 1. The process does not involve heating at high temperature which is undesirable for heat labile astaxanthin. 2. Hot air drying of the composition at 40-50°C is sufficient to obtain dry powder. 3. Food grade solvents can be used for in the process hence considered safe. 4. Starch is used as edible matrix to make the process more efficient, in addition to other matrices, such as dextrin, maltodextrin, ß-cyclodextrin which provides a range of utilities for various products. 5. Water soluble astaxanthin composition can be used to improve the nutraceutical value and to improve the color of food formulations. WE CLAIM: 1. A process for the preparation of water dispersible astaxanthin composition which comprises: (g) dissolution of astaxanthin in known food grade solvent in a 1:0.5 to1: 1.2 to obtain astaxanthin solution; (h) simultaneously dissolving the edible matrix of the kind such as herein described in water in a ratio of 10:1 to 12:1 to obtain an aqueous matrix; (i) boiling the aqueous matrix as obtained in step [b] in the presence of stabilizing agents of the kind such as herein described; (j) homogenizing the astaxanthin solution as obtained in step [a] with hot aqueous solution of edible matrix as obtained in step [c]; (k) evaporating the solvent to get a solid; (I) drying the solid as obtained in step [e] at 40 to 50 degree C to obtain the desired water soluble astaxanthin composition. 2. A process as claimed in claim 1, wherein the food grade solvent is selected from the group consisting of acetone, dichloromethane, isobutyl acetate, isobutyl acetate, n-butyl alcohol, heptane, iso-amyl alcohol. 3. A process as claimed in claim 1, wherein the edible matrix is selected from the group consisting of starch, dextrin, maltodextrin, ß-cyclodextrin. 4. A process as claimed in claim 1, wherein the stabilizing agent is selected from the group consisting of gum acacia, ascorbic acid and citric acid. 5. A process as claimed in claim 1, wherein the stabilizing agent is incorporated at 0.5-2.0% level in the composition. 6. A process as claimed in claim 1, wherein evaporation of the solvent is done by vacuum distillation. 7. A process for the preparation of water dispersible astaxanthin composition substantially as herein described with references to the examples.

Documents:

712-DEL-2007-Abstract-(20-03-2008).pdf

712-del-2007-abstract.pdf

712-del-2007-Claims-(07-07-2014).pdf

712-DEL-2007-Claims-(20-03-2008).pdf

712-DEL-2007-Claims-151214.pdf

712-del-2007-Correspondence Others-(07-07-2014).pdf

712-DEL-2007-Correspondence-151214.pdf

712-DEL-2007-Correspondence-Others-(28-04-2009).pdf

712-del-2007-correspondence-others.pdf

712-DEL-2007-Description (Complete)-(20-03-2008).pdf

712-del-2007-description (provisional).pdf

712-del-2007-form-1.pdf

712-DEL-2007-Form-18-(28-04-2009).pdf

712-DEL-2007-Form-2-(20-03-2008).pdf

712-del-2007-form-2.pdf

712-del-2007-form-3.pdf

712-del-2007-form-5.pdf