Two-phase fermentation process for the production of an organic compound

Abstract

The invention relates to a two phase fermentation process for producing an organic compound, in particular an isoprenoid and to a bioreactor comprising a two phase fermentation system for producing an organic compound.

1 . A two-phase fermentation process for the production of an organic compound, preferably an isoprenoid, comprising the steps of:
 a) adding a water-immiscible organic solvent to an aqueous medium for culturing cells to form a two phase system, wherein the ratio of water-immiscible organic solvent to aqueous medium is between 0.5% (v/v) and 60% (v/v) and the total volume of solvent and medium is at least 10 L;   b) providing the two phase system with an oxygen probe; then   c) performing a calibration of said oxygen probe; then   d) optimizing oxygen tension in said two phase system; then   e) inoculating said two phase system with a microorganism capable of producing said isoprenoid in said oxygen optimized two phase system; then   f) measuring and optimizing oxygen tension; and   g) allowing said microorganism to produce said organic compound.   
     
     
         2 . Process according to  claim 1 , wherein the total volume of solvent and medium is at least 30 L, preferably at least 100 L, more preferably at least 1,000 L, more preferably at least 10,000 L, most preferably 30,000 L or more. 
     
     
         3 . Process according to  claim 1 , wherein the process further comprises sterilizing the two phase system prepared in step a), preferably by sterilization for at least 20 minutes at at least 120° C., wherein the sterilization takes place before step e), preferably before step c). 
     
     
         4 . Process according to  claim 1 , wherein the process further comprises the isolation of the organic compound from the two phase system, preferably from the water-immiscible organic solvent. 
     
     
         5 . Process according to  claim 1 , wherein the water-immiscible organic solvent is a liquid alkane or a long-chain aliphatic alcohol or an ester of a long-chain fatty acid or an isoprenoid. 
     
     
         6 . Process according to  claim 1 , wherein the water-immiscible organic solvent is dodecane, lauric acid, oleic acid, n-decane, butyl stearate, olive oil, corn oil or DINP, preferably dodecane. 
     
     
         7 . Process according to  claim 1 , wherein the microorganism is a Gram positive bacterial cell, a Gram negative bacterial cell, a fungal cell, a transgenic plant or culture comprising a transgenic plant cell or a transgenic mushroom or culture comprising a transgenic mushroom cell. 
     
     
         8 . Process according to  claim 1 , wherein the percentage of water-immiscible organic solvent in the two-phase system is between 2% (v/v) and 40% (v/v), preferably between 5% (v/v) and 20% (v/v), most preferably between 10% (v/v) and 20% (v/v). 
     
     
         9 . Process according to  claim 1 , wherein the organic compound is an isoprenoid, preferably a monoterpene, a sesquiterpene, a diterpene or a triterpene. 
     
     
         10 . Process according to  claim 1 , wherein the dissolved oxygen during the production phase step (f) never exceeds 80%, preferably 60%, more preferably 40%, most preferably 20%. 
     
     
         11 . Bioreactor comprising at least 10 L of a two phase system comprising a water-immiscible organic solvent and an aqueous medium for culturing cells, wherein the ratio of water-immiscible organic solvent to aqueous medium is between 0.5% (v/v) and 60%. 
     
     
         12 . Bioreactor according to  claim 11 , further comprising a microorganism capable of producing an organic compound, preferably an isoprenoid. 
     
     
         13 . Bioreactor according to  claim 11 , further comprising an oxygen probe. 
     
     
         14 . Bioreactor according to  claim 1 , wherein the organic solvent is a liquid alkane or a long-chain aliphatic alcohol or an ester of a long-chain fatty acid or an isoprenoid, preferably dodecane, lauric acid, oleic acid, n-decane, butyl stearate, olive oil, corn oil or DINP, more preferably dodecane. 
     
     
         15 . Bioreactor according to  claim 1 , wherein the microorganism is a Gram positive bacterial cell, a Gram negative bacterial cell, a fungal cell, a transgenic plant or culture comprising a transgenic plant cell or a transgenic mushroom or culture comprising a transgenic mushroom cell.