Title of Invention

A PROCESS OF PREPARING A NEW SOLUBLE OF (-) HYDROXYCITRIC ACID FROM GARCINIA EXTRACTS

Abstract

t This invention relates to a process for preparing a new (67) Abtract' soluble double metal salt of group lA and IIA of (-)hydroxy-cltric acid from Garcinia extracts comprising step i-extracting Garcinia cambogia rind with polar solvent of the hind as herein described and filtering, step-2-heating the filtrate in vacuo at 50-80 c to evaporate the said polar solvent, step 3-reraoving in any known manner the water insoluble substances to get the (-)hydroxycltric acid concen¬trate. Step 4-decolorlzing the said (-)hydroxyoitric acid with 2-5X of activated charcoal and filtering, step 5-neutralizing the filtrate with group lA metal hydroxides. Step 6-partlally displacing the group lA metal ions in the above salt solutions by adding group IIA metal chlorides to form soluble double metal salt of group lA and IIA of (-)hydroxycitrlc acid, step 7-precipitating in a conventional manner the said solubilised group lA & IIA metal salts of (-)hydroxycitric acid by adding aqueous polar solvent to get soluble lA & IIA metal salt of (-)hydroxycitrie acid and if desired spray drying it to obtain the soluble metal salt in powder form.

Full Text

This invention relates lo a process of preparing a new soluble double metal salt of group lA and IIA of (-) hydroxycitric acid from Garcin extracts. The product obtained by the process with >98% purity can be used safely not only as a food supplement in various nutrieutical formulations and beverages but also for effecting obesity control. BACKGROUND (-) Hydroxycitric acid (HCA) occurs in the fruit rind of Garcinia species (G. Cambogia, G. indica and G. atroviridis). The first two species grow abundantly in India and the third occurs mostly in South East Asian countries. The success of this natural food product derived from Garcinia fruit has been documented and been in use since several centuries BC. Also known as "Kokum", the extracts of the fruit have been used as a tart flavoring in meat and seafood dishes, turned into a refreshing beverage that serves as a unique flavor enliancer, gourmet spice and a digestive after a heavy meal. In Ayurveda, the traditional ancient system of herbal medicine in India, Garcinia is also considered to be one of the prime herbs that are beneficial for the heart. In more recent times, Garcinia has received worldwide attention as a nutriceutical for effective obesity control. Several scientists including ai PIoffman-La Roche have established that HCA, the active ingredient in the fruit, prevents the conversion of excess carbohydrates to fat in animals. The energy released by the excess carbohydrate is converted into and stored as glycogen, a readily usable form of energy. Interestingly, it has been shown to inhibit ATP dependent ciUrate-lyase, a key enzyme in diverting carbohydrate to fatty acids and cholesterol synthesis. (Sullivan et al Lipids, 9:121 and 129 (1973), Sergio, W., Medical Hypothesis 27:39 (1988)). The age-old practice of consuming Garcinia rind as a food additive by inhabitants of Malabar and Konkan coast of the Indian peninsula has established the safety of HCA. The isolation and chemical nature of (-) hydroxycitric acid from Garcinia rind are described in the publication of Lewis Y.S., et al (Methods in Enzymology, 13:613 (1967),and in the patents (Indian patents 160753 & 178298 and US patents 5536516 & 5656314). It is believed that consumption of MCA influences the body metabolism leading to the saturation of glycogen receptors in the liver and a consequent transmission of signals of satiation to brain. Even as,a food supplement, (-) HCA helps a person to lose/control weight in a natupltl way without affecting normal physical activities. In view of its unique property, several health care formulations incorporating HCA are being sold across the counter in the Western markets. These include tablets, capsules, herbal teas, chocolate bars, milk shakes and other beverages, The active ingredient (HCA) from this insoluble HCA salt is released upon contact with hydrochloric acid in the stomach and absorbed through the intestine to exert its metabolic effect. There is prior art on the preparation of a soluble tri-potassium salt of {-) HCA (Lewis Y.S., et al (Methods in Enzymology, 13:613 (1967), hiternational Patent WO 96/36585, US patent 08/440,968 filed). However, its alkaline nature and risks associated with the consumption of high potassium (~36%) makes this product unsuitable for HCA-based formulations. In our earlier patents (Indian patent No. 178298 & US patents 5536516, 5656314) which describes preparation of a concentrate of (-) hydroxycitric acid and its lactone in liquid form, comprising of several steps like water extraction of Garcinia rind containing (-) hydroxycitric acid and its concentration, acetone refinement of this concentrated water extract, evaporation of acetone, loading thus obtained refined extract on ion-exchange columns containing an anion exchange resin followed by a cation exchange resin, and finally evaporation of the free acid liberated from the ion-exchange process to said concentration. This liquid form of (-) hydroxycitric acid has problems of stability and half-life. In addition, its highly acidic nature poses problems in formulating into beverage and various other food products without affecting their flavor and properties. The object of this invention is to overcome the above drawbacks by developing a process for the preparation of a new soluble double metal salt of (-) hydroxycitric acid from Garcinia extracts. To achieve the said objective, this invention provides a process lor preparing a new soluble double metal salt of group lA and IIA of (-) hydroxycilric acid of general formula I and more particularly formula H as given below from Garcinia extracts: displacing partially group lA metal ions in the above salt solutions by adding group IIA metal chlorides to form soluble double metal salt of group lA and IIA of (-) hydroxycitric acid, precipitating the said solubilised group IIA metal salts of (-) hydroxycitric acid by adding aqueous polar solvent to get soluble IIA metal salt of (-) hydroxycitric acid The soluble metal salt of (-) hydroxycitric acid is obtained in powder form by spray drying prior to the solvent addition or spray drying water solubilised solvent precipitated material. The free (-) hydroxycitric acid present in the step 2 is neutralized by three equivalents of group lA metal hydroxides. Partial displacement of group lA metal ion in step 3 is carried out with 3 equivalent of group IIA metal chloride. The group IIA metal chloride was added drop wise with vigorous stirring and the soluble group IIA metal salt of (-) hydorxycitric acid is precipitated by adding ethanol. Group lA hydroxides used LiOH, NaOH, KOH, RbOH, CsOH and FrOH Group IIA metal chlorides BeCb, MgCb, CaCh, SrCh, BaC^and RaC12 The said polar solvents are methanol, ethanol, propanol, isopropanol, acetone or aqueous acetone (80% acetone in water). The soluble double metal salt of group lA and IIA of (-) hydroxycitric acid is soluble sodium calcium salt of (-) hydroxycitric acid The invention will now be described with reference to the following example ; EXAMPLE One hundred gm Garcinia Cambogia rind was extracted 4 times with 80% acetone in water (250 ml each time) for 4 hours. The combined extract (830-ml) was concentrated to 300 ml by heating in vacuo at 56 C (500 millibar and filtered through cheese cloth to remove water insoluble non polar substances. The filtrate (260-ml) containing 18 gm of hydroxycitric acid decolorized by addition of 2.6 gm of activated charcoal and tlltered. The resultant clear solution was concentrated to 50 ml, and the free acid was converted into the sodium salt of hydroxycitric acid by the addition of 11 gm of sodium hydroxide pellets, were added. To this formed solution of sodium salt of (-) hydroxycilric acid 20 ml of solution containing 9 gm of calcium chloritlc was added drop wise with vigorous stining. The soluble salt of hydroxycilric acid is then. precipitated by addition of ethanol. The precipitated sail is filtered, washed with ethanol and dried to obtain 20.7 gm of the soluble calcium salt of hydroxycitric acid (yield 89.84%). We Claims: 1. A process for preparing a new soluble double metal salt of group . JA and 11A of (-) hydroxycitric acid of general formula I and more particularly formula II as given below from Garcinia extracts: displacing partially group lA metal ions in the above salt-solutions by adding group IIA metal chlorides to form soluble double metal salt of group IA and HA of (-) hydroxycitri^ acid, - precipitating the said solubilised group IIA metal salts of (-) hydroxycitric acid by adding aqueous polar solvent to get soluble IIA metal salt of (-) hydroxycitric acid. 2. A process as claimed in claim 1 wherein soluble metal salt of hydroxycitric acid is obtained in powder form by spray drying prior to the solvent addition or spray dr>'ing water solubilised solvent precipitated material. 3. A process as claimed in claim 1 wherein the free (-) hydroxycitric acid present in step 2 is neutralized by three equivalents of group lA metal hydroxides. 4. A process as claimed in claim 1 wherein partial displacement of group lA metal ion in step 3 is carried out with one equivalent of group IIA metal chloride. 5. A process as claimed in claim 1 wherein the group IIA metal chloride was added drop wise with vigorous stirring and the soluble group IIA metal salt of (-) hydorxycitric acid is precipitated by adding ethanol. 6. A process as claimed in claim 1 wherein the said (-) hydroxycitric acid concentrate is decolorized by heating with 2-5% activated charcoal, if desired. 7. A process as claimed in claim 1 wherein group lA metal hydroxides used are LiOH, NaOH,, RbOH, CsOH and FrOH and group IIA metal chlorides used are BeCb, MgCb, CaCb, SrCb, BaCb and RaCb. 8. A process as claimed in claim 1 wherein tlie said polar solvents are methanol, ethanol, propanol, isopropanol and acetone. 9. A process as claimed in claim 1 wherein the aqueous polar solvent is 80% acetone in water. 10. A process as claimed in claim 1 of the preceding claims wherein soluble group IIA metal salt of (-) hydroxycitric acid is soluble calcium' salt of (-) hydroxycitric acid. 11. A process for preparing a new soluble double metal salt of group lA and IIA of (-) hydroxycitric acid of general formula I and more particularly formula II substantially as herein described with reference to the forgoing example.

Documents:

1986-mas-1997 abstract.pdf

1986-mas-1997 claism.pdf

1986-mas-1997 correspondence-others.pdf

1986-mas-1997 correspondence-po.pdf

1986-mas-1997 description (complete).pdf

1986-mas-1997 form-1.pdf

1986-mas-1997 form-26.pdf

1986-mas-1997 form-4.pdf

1986-mas-1997 form-6.pdf

1986-mas-1997 petition.pdf