Process for the Isolation and Stabilization of Low-Molecular Weight Aminoglycans from Waste Egg Shells

Abstract

Processes for the isolation of low-molecular weight aminoglycan compound of formula I from a hitherto unexploited natural source of waste egg shells which is made up of alternating glucuronic acid and N-acetyl glucosamine units comprising the steps of: (a) pre-preparation of the waste egg-shells for extraction of the embryonic low molecular weight aminoglycan compound of formula I using a polar organic solvent in water; (b) extraction of the low molecular weight aminoglycan compound of formula I as its soluble salt using an aqueous polar salt solution; (c) isolation of a purified low molecular weight aminoglycan compound of formula I by gel formation out of the aqueous salt mixture by using a polar organic solvent followed by filtration or centrifuging; (d) stabilization of the isolated aminoglycan extract by sequential introduction of organic oils into a semi-dried gel to form ordered sheets of aminoglycan compound of formula I with no visible cross-linking of the carbohydrate polymer.

1 . A process for the isolation of low-molecular weight aminoglycan compounds of formula I from waste egg shells,  
       
         
           
           
               
               
           
         
         wherein M may be one or more instances of Na, Ca, K, Mg and n is an integer between 20 and 40;  
         said Process comprising the steps of:  
         (a) pre-preparation of the waste egg-shells for extraction of the embryonic low molecular weight aminoglycan compound of formula I using a polar organic solvent in water, wherein the pretreated egg shells are mixed thoroughly with the polar organic solvent in water at temperatures between 25° C. and 40° C. for 1 hour to 4 hours, followed by decantation of the supernatant and the eggshells carried forward for extraction;  
         (b) extraction of the low molecular weight aminoglycan compound of formula I as its water soluble salt using an aqueous polar salt solution, wherein the eggshells from step (a) are vigorously shaken with the aqueous polar salt solution at 25° C. to 40° C. for 6 to 24 hours, followed by decantation, filtration or centrifugation to collect the aqueous layer containing the dissolved aminoglycan compound of formula I;  
         (c) isolation of a purified low molecular weight aminoglycan compound of formula I by gel formation out of the aqueous salt mixture by using a polar organic solvent, wherein the solution from step (b) is subjected to sequential step wise addition of the polar organic solvent in an amount between 75% and 150% volume/volume of the polar organic solvent between 10° C. and 20° C. in 1 hour to 2 hours and the gel formed is allowed to stand for 4 hours to 12 hours to complete precipitation, followed by decantation, filtration or centrifugation to isolate semi dried aminoglycan compound of formula I containing between 4% to 8% of moisture;  
         (d) stabilization of the isolated aminoglycan compound of formula I from step (c) by sequential introduction of organic oils into the semi-dried gel to form the aminoglycan compound of formula I.  
       
     
     
         2 . The process as claimed in  claim 1 , wherein the polar organic solvent used in step (a) is selected from the group consisting of an alcohol, acetone, methylethylketone or 1,4-dioxane.  
     
     
         3 . The process as claimed in  claim 1 , wherein the said aqueous polar salt solution used in step (b) is an organic acid salt selected from the group consisting of sodium, potassium, calcium or magnesium salt of citrate, glutamate, acetate, pyrrolidone carbonate, tartrate, glycinate, sulfate sulfite, nitrate, carbonate or oxalate.  
     
     
         4 . The process as claimed in  claim 1 , wherein the polar organic solvent used in step (c) is a lower alcohol selected from methanol, ethanol, propanol or butanol, or an organic ether selected from diethylether, tetrahydrofuran, methylal or ethylal.  
     
     
         5 . The process as claimed in  claim 1 , wherein the organic oils used in step (d) are the oils obtained from plant sources.  
     
     
         6 . The process as claimed in  claim 5 , wherein the said organic oil is selected from jojoba, almond, sage, rosemary, lavender, sandalwood or aloe oil.