Title of Invention

A METHOD OF ISOMERISATION OF CIS CAROTENOIDS TO TRANS CAROTENOIDS

Abstract

The process of the present invention relates to the isomerisation of cis carotenoids to (ran..\' carotenoids using a infrared rays. This involves the direct exposure of harvested algal biomass or the separated of natural mixed carotenoid product to infrared rays wherein the isomerisation is effected directly. The source of the carotenoids is preferably from the alga dunaliella Salina. Thus both the natural mixed carotenoid product and the crystalline product thus obtained contains the other essential carotenoids such as alpha carotene, lute in, zeaxanthin in its various proportions. A suitable solvent is used for the extraction (}f biomass to obtain crystals of alltrans Bctacarotene, or by separation of the exposed natural mixed carotenoid extract by solvent separation to obtain alltrans betacarotence thereby rendering high purity Betacarotene from both t he above methods.

Full Text

The process of the present invention relates to isomerisation of cis carotenoids to trans carotenoids using infrared rays. It is an object of the present invention to provide a simplified method for the conversion of the cis carotenoid to the all trans carotenoid forms. PRIOR ART: Carotenoids are the most widespread class of naturally occurring pigments in nature, present in photosynthetic tissue and occurring with no definite pattern in non-photosynthetic tissues such as root, flower petals, seeds and fruits. They are also present in algae, fungi, yeasts, molds, mushrooms and bacteria and in many cases they are the major pigment in the exoskeleton of aquatic and avian species. Carotenoids and/or carotenes derive their names from the fact that they constitute the major pigment in the carrot root, one of the first foods observed to possess this class of pigments. All trans Beta-carotene is generally considered as a class prototype. Beta-carotene is a symmetrical molecule of 40 carbon atoms, consisting of 8 isoprene units, having 11 conjugated double bonds, and possessing two Beta-ionone rings at the end of the molecule. Beta-carotene is of particular importance due to representing a major dietary source of vitamin A and also it serves as excellent colorants and is the most prevalent in nature. Carotenoid providing a source of vitamin A. Vitamin A or retinol has long been known to be necessary to the biochemistry of vision and to the proper U.S. Patent Application No. 20020082459 of David T, Bailey et al., discloses a process for concentrating algae using ultra filter, and the mass is extracted using heptanes. The extract is then concentrated to a viscous alga oil which is heated at 120 Deg C for a period of 24 hours for the isomerisation. U.S. Patent No. 3, 989,757 to Surmatis et al., discloses a process wherein temperatures of about 50 to 120 degree C are utilized for the isomerization procedure. Preferably, heating of the cw-isomer is carried out until analysis of the carotenoid shows only the all-trans-isomer to be present. The isomerisation procedure is performed for a period of 20 hours from the cis isomers to the corresponding all trans-xsovciQX. Field of the Invention: The process of the present mvention relates to the isomerisation of cis carotenoids to trans carotenoids using infrared rays. This involves the direct exposure of harvested algal biomass of natural mixed carotenoid product to infrared rays wherein the isomerisation is effected directly. The source of the carotenoids is preferably from the alga Dunaliella salina. Thus both the natural mixed carotenoid product and the crystalline product thus obtained, contains the other essential carotenoids such as alpha carotene, lutein, zeaxanthin in its various proportions. A suitable solvent is used for the extraction of biomass to obtain crystals of trans Betacarotene, or by separation of the exposed natural mixed carotenoid extract by solvent separation to obtain trans Betacarotene. Thereby rendering high purity Betacarotene from both the above methods. DETAIL DESCRIPTION OF THE INVENTION; It is an object of the present invention to provide a simplified method for the conversion of the cis carotenoid to the all trans carotenoid forms using infrared rays from an infrared source. It is also an object of the present invention to increase the yield of all trans Beta.-carotene. Additional objects of this invention shall be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following specification or may be leamed by the practice of the invention. The objects and advantages of the invention attained by means of the instrumentalities, combinations and methods particularly pointed out in the appended claims. The method of this invention comprises of exposure of concentrated algal biomass or concentrated natural mixed carotenoid to infra red rays to isomerise the cis carotenoids to all trans carotenoids and wherein the all trans carotenoid is obtained in higher quantity and of high purity. The present invention is also directed to a composition of naturally obtained all trans Beta-carotene having a purity level greater than 85%. The present invention relates to the isomerisation of natural carotenoids which are present in its native forms of which the predominat are the cis forms which is successfully isomerised very efficiently in a more simplified manner by infrared rays to all trans carotenoids. This step of isomerisation is achieved in the native plant form or the solvent extract concentrated natural mixed carotenoid extract form. The all trans Beta-carotene compounds are then crystallized with the addition of cold solvent. The Beta-carotene containing compositions of the present invention is prepared from a variety of plant materials, such as algae, palms, vegetables such as spinach, broccoli, alfalfa, and other plants. Preferably the plants are algae. Among the algae, the preferred classes are Chlorophyta (green algae), of which the preferred algae is Dunaliella salina. First part of the invention wherein the algal biomass is used directly to effect isomerisation process. The algal biomass is obtained from by growing them in shallow tanks, bioreactors, man-made or natural ponds at a wide range of temperatures. Preferably the culture medium is salt water, but fresh water can also be used. Fresh water may be made saline by the addition of salt as a culture medium. The medium may be supplemented by the addition of nitrate, phosphate, bicarbonate, iron and trace minerals. Protocols for the large scale propagation of algae are described in, for example, Richmond, A., Handbook of Microalgal Mass Culture, CBC Press, Boca Raton, Fla., (1986), and Ben-Amotz, A., Algal and Cyanobacterial Biotechnology, Longman Scientific and Technical Press, pp. 90- 114, (1989), both of which are incorporated herein by reference. When the algal culture reaches the desired density, such as about 0.25 to 0.5 grams dry weight/liter, as determined by absorbance, the algae are harvested from the tank or pond by pumping out the water slurry containing the dispersed algae. The slurry is passed through screens which are sufficiently coarse to allow algae through but which remove larger unwanted objects. In the preferred embodiment, the slurry is dewatered and concentrated by, flocculation and followed centrifugation. The concentrated biomass is then is suspended in a ribbon blender or a sigma blender. The infrared source is suspended in a network from above. The hight of the infrared source to the algal biomass is maintained at about 10 to 12 inches. The biomass is exposed to 9 commercially available infrared bulbs of 25 OW capacity. The exposure lasts from 45 min to 2 hours. Samples are drawn periodically to check the isomerisation process of cw carotenoids to trans carotenoids. At the end of the process about 60 % of the cis isomer is converted to the trans form. The alga is then extracted using ethyl acetate at room temperature. The extract is then filtered and concentrated in vacuo at 45 deg C. and the extract is allowed to stand for 2 hours. Crystallisation is effected and the concentrate is filtered to obtain all-trans crystal of about 85% purity. The crystal thus obtained contains other carotenoids such as alpha carotene, lutein zeaxanthin and traces of cis carotenoids. The second part of the invention is to use the natural mixed carotenoid extract for the process of isomerisation. This is performed by extraction of the wet algal biomass using ethyl acetate and concentrated in vacuo at 45 deg C. The extract thus obtained is then added to a planetary mixer. The infrared lamps are suspended from the top. The extract is exposed to 4 bulbs of infrared source of 250W capacity. The source of the lamp is about 10 to 12 inches from the surface of the extract. The constant mixing exposes the extract completely to infrared rays. This procedure is performed for a period of 2 hours until the isomerisation comes to saturation. After completion of the process isopropyl alcohol is added to the natural mixed carotenoid extract under constant agitation to crystallize the all trans isomer. The extract is then filtered to obtain thye all trans Beta- carotene of high purity. After filteration the crystals are washed with ice cold isopropyl alcohol and the crystals are dried in vacuo at 60 deg C for 24 hrs. EXAMPLE 1: Isomerisation of cis Betacarotene to all trans Betacarotene by exposure to Infra red rays directly on the algal biomass. To 250kg flocculated and centrifiiged wet algal biomass of Dunaliella salina is added to a blender. The algal biomass is continuously stirred at 40 rpm. The biomass is exposed to 9 bulbs of infrared source of 250W capacity. The exposure is for a period of 2 hours. Samples are drawn continuously and after the completion of isomerisation, the wet algal biomass is extracted with 400 litres of ethyl acetate. The extract thus obtained is filtered to remove any solid material and is concentrated in vacuo to obtain a concentrated extract of 2500ml. This volume is allowed to stand for two hours and filtered. The crystals obtained (1223gms) are all trans Betacarotene of the purity of >85%. The crystals thus obtained are washed finally with ice cold isopropyl alcohol and dried in vacuo at 60 deg C for 24 hrs. Example 2 To 250kg flocculated and centrifuged wet algal biomass of Dunaliella salina is added to a belnder. The algal biomass is continuously stirred at 40 rpm. The wet algal biomass is extracted with 400 litres of ethyl acetate. The extract thus obtained is filtered to remove any solid material and is concentrated in vacuo to obtain a concentrated extract of 2500mL The extract is added to a 5 liter planetary mixer and continuously stirred during the exposure to infrared rays. The extract is exposed to 4 bulbs of infrared source of 250W capacity. The exposure was for a period of 2 hours. Samples are drawn continuously and after the completion of isomerisation This volume is allowed to stand for two hours and filtered . The crystals obtained (1123gms) are all trans Betacarotene of the purity of >85%. The crystals thus obtained are washed finally with ice cold isopropyl alcohol and dried in vacuo at 60 deg C for 24 hrs. We claim, 1. A method for the isomerisation of cis carotenoid to trans carotenoid using infrared rays comprising the steps of: (a) adding flocculated and centriftiged wet algal biomass of Dunaliella salina in a blender; (b) stirring the algal biomass continuously; (c) extracting the wet algal biomass with the solvent; (d) filtering the extract and concentrating in vacuo; (e) either exposing the biomass obtained in step (b) to the infrared source and then following the steps (c) and (d) and or otherwise exposing the extract obtained in step (d) to the infrared source with continuous stirring during the course of exposure; (f) allowing the extract to stand for 2 hours; (g) washing of obtained crystals with the solvent and drying in vacuo. 2. The method of isomerisaiton of cis carotenoid to trans carotenoid as claimed in claim 1 wherein said source of isomerisation is infrared rays, 3. The method of isomerisation of cis carotenoid to trans carotenoid using infrared rays as claimed in claim 1 wherein said algae is Dunaliella salina. 4. The method of isomerisation of cis carotenoid to trans carotenoid using infra red rays as claimed in claim 1 wherein said selected time of infrared rays exposure is 120 minutes at the height of 10 to 12 inches from the surface. 5. The method of isomerisation of cis carotenoid to trans carotenoid using infrared rays as claimed in claim 1 wherein said carotenoid is Beta- carotene. 6. The method of isomerisation of cis carotenoid to trans carotenoid using infrared rays as claimed in claim 1 wherein the solvent used for extraction of biomass is ethyl acetate. 7. The method of isomerisation of cis carotenoid to trans carotenoid using infrared rays as claimed in claim 1 wherein the solvent used for crystallisation of natural mixed carotenoid complex is isopropyl alcohol. 8. The method of isomerisation of cis carotenoid to trans carotenoid using infra red rays as claimed in claim 1 wherein the all trans Betacarotene obtained from both the processes are >85% pure. 10. The method of isomerisation of cis carotenoid to trans carotenoid using infrared rays as claimed in claim 1 wherein the all trans Betacarotene crystal also contains other beneficial carotenoids such as lutein, zeaxanthin, and alpha carotene. 11. A method for the isomerisation of cis carotenoid to trans carotenoid using infrared rays as claimed in claim 1 to 9 as substantially herein described

Documents:

392-che-2003-abstract.pdf

392-che-2003-claims duplicate.pdf

392-che-2003-claims original.pdf

392-che-2003-correspondnece-others.pdf

392-che-2003-correspondnece-po.pdf

392-che-2003-description(complete) duplicate.pdf

392-che-2003-description(complete) original.pdf

392-che-2003-description(provisional).pdf

392-che-2003-form 1.pdf

392-che-2003-form 19.pdf

392-che-2003-form 26.pdf

392-che-2003-form 3.pdf

392-che-2003-form 5.pdf