Method of Precipitating Phytase

Abstract

Herein is disclosed a process for effectively precipitating phytase as a complex with a polyanion, as well as compositions comprising phytase and a polyanion, and a method for manufacturing such compositions.

1 - 19 . (canceled) 
     
     
         20 . A method of precipitating phytase comprising
 i. providing an aqueous medium comprising phytase; and   ii. adding polyanion; and   wherein no Ca 2+  is added to the aqueous medium during the method.   
     
     
         21 . The method of  claim 20 , wherein the aqueous medium comprising phytase comprises fermentation broth. 
     
     
         22 . The method of  claim 20 , wherein the aqueous medium comprising phytase comprises clarified fermentation broth, spent fermentation broth, spent and clarified fermentation broth, or a combination thereof. 
     
     
         23 . The method of  claims 20 - 22 , wherein the dry matter content of the aqueous medium comprising phytase without solids is between 0.1-25% w/w before step ii. 
     
     
         24 . The method of  claims 20 - 23  comprising setting pH to 3-5 for enhancing precipitation of phytase. 
     
     
         25 . The method of  claims 20 - 24 , wherein the polyanion is alginic acid, pectic acid, hyaluronic acid, phytic acid, a salt of such a polyanionic acid, or any combination thereof. 
     
     
         26 . The method of  claim 25 , wherein the salt of the polyanionic acid is added in a solid form or as an aqueous solution to the aqueous solution comprising phytase. 
     
     
         27 . The method of  claims 20 - 26  wherein the concentration of CaCl 2  is below 5 mM, 2 mM or 1 mM. 
     
     
         28 . A method of preparing a phytase composition comprising
 i. providing an aqueous medium comprising phytase;   ii. adding a polyanion for precipitating phytase as a complex of phytase and polyanion; and   iii. directly recovering the precipitated phytase to obtain the phytase composition, and   wherein no Ca 2+  is added to the aqueous medium during the method.   
     
     
         29 . The method of  claim 28 , comprising washing the precipitated phytase. 
     
     
         30 . The method of  claims 28 - 29  wherein the precipitated, optionally washed, phytase is dehydrated to obtain a dry product. 
     
     
         31 . The method of  claims 28 - 30  comprising dissolving of the precipitated phytase to obtain a liquid product. 
     
     
         32 . The method of  claims 28 - 31 , comprising dehydrating the precipitated, optionally washed, phytase to obtain a dry product. 
     
     
         33 . The method of  claim 32 , comprising dissolving the dry product to obtain a reconstituted product. 
     
     
         34 . The method of  claims 20 - 33  wherein the ratio of phytase to polyanion expressed as FTU:mg polyanion is selected from the range 500-15000. 
     
     
         35 . The method of  claims 20 - 34 , wherein the amount of the added polyanion is selected from the range of 0.001-2% w/w based on dry matter content. 
     
     
         36 . A phytase composition comprising phytase complexed with a polyanion, and not containing added Ca 2+ . 
     
     
         37 . The phytase composition of  claim 36  wherein the polyanion is alginic acid, pectic acid, hyaluronic acid, phytic acid, a salt of such a polyanionic acid, or any combination thereof. 
     
     
         38 . The phytase composition of  claims 36 - 37 , wherein the composition is a liquid product or a dry product.