Extraction and Fractionation of Biopolymers and Resins from Plant Materials

Abstract

A method for the extraction, separation, fractionation and purification of biopolymers from plant materials using supercritical and/or subcritical solvent extractions is disclosed. Specifically, the process can be used for the separation of resins and rubber from guayule shrub ( Parthenium argentatum ), and other rubber and/or resin containing plant materials, using supercritical solvent extraction, for example supercritical carbon dioxide extraction. Additionally, polar and/or non-polar co-solvents can be used with supercritical carbon dioxide to enhance the selective extraction of resins and rubbers from the shrub.

1 . A method for removing rubber and resin from plant material, comprising: 
 preparing the plant material for supercritical extraction;    extracting resins from the plant material using supercritical solvent extraction; and    extracting rubber from the plant material using a co-solvent.    
   
   
       2 . The method of  claim 1 , wherein preparing the plant material includes pre-treating the plant material.  
   
   
       3 . The method of  claim 1 , wherein the plant material is selected from a group consisting of virgin feedstock, bagasse and previously-extracted plant material.  
   
   
       4 . The method of  claim 1 , wherein the plant material is derived from a non-Hevea plant.  
   
   
       5 . The method of  claim 1 , where in the plaint material is guayule.  
   
   
       6 . The method of  claim 1 , wherein the solvent used in the supercritical extraction of the resin is a polar solvent.  
   
   
       7 . The method of  claim 1 , wherein the co-solvent is a non-polar solvent.  
   
   
       8 . The method of  claim 1 , wherein the co-solvent is hexane.  
   
   
       9 . The method of  claim 1 , wherein the co-solvent is iso-octane.  
   
   
       10 . The method of  claim 1 , wherein the co-solvent is cyclohexane.  
   
   
       11 . The method of  claim 1 , wherein the co-solvent is water.  
   
   
       12 . The method of  claim 1 , wherein the co-solvent is ethanol.  
   
   
       13 . The method of  claim 1 , wherein the co-solvent is acetone.  
   
   
       14 . A commercial accelerated solvent extraction process, comprising: 
 mixing a sample of plant material with sand;    centrifuging the mixture according to a pre-determined protocol;    rinsing the mixture with a polar solvent, wherein the polar solvent is capable of producing a polar solvent extract; and    rinsing the mixture with a non-polar solvent, wherein the non-polar solvent is capable of producing a non-polar solvent extract.    
   
   
       15 . The method of  claim 10 , further comprising drying the polar solvent extract and the non-polar solvent extract.  
   
   
       16 . An apparatus for selectively extracting a biopolymer from plant materials, comprising: 
 an extraction vessel, wherein the extraction vessel is capable of maintaining a solvent at a supercritical pressure and temperature;    a cylinder, fluidly coupled to the pressure vessel, wherein the cylinder is capable of holding a supercritical solution; and    a bed of ground plant material, fluidly coupled to the cylinder, wherein the bed is capable of extracting the biopolymer from the supercritical solution.    
   
   
       17 . The apparatus of  claim 16 , wherein the plant material is derived from a non-Hevea plant.  
   
   
       18 . The apparatus of  claim 16 , wherein the plant material is guayule.  
   
   
       19 . The apparatus of  claim 16 , wherein the biopolymer is a non-resin biopolymer.  
   
   
       20 . The apparatus of  claim 19 , wherein the non-resin biopolymer is rubber.  
   
   
       21 . The apparatus of  claim 16 , wherein the bed is further capable of extracting a resin from the supercritical solution.