Use of bacteria for the production of bioenergy

Abstract

The present invention relates to composition and methods of producing bioenergy. More specifically, the invention relates to the use of bacterium of the genus Deinococcus and/or related genera for the modification of biomass or biomass derivatives with a view to producing bioenergy products and metabolites.

We claim: 
     
         1 . A method of production of an organic acid comprising contacting vegetal biomass comprising xylan, cellulose and/or hemicellulose with a bacterium of the genus  Deinococcus  or with an extract of said bacterium, culturing said  Deinococcus  in contact with said vegetal biomass to produce an organic acid or reacting said extract with said vegetal biomass under conditions that permit the formation of an organic acid and collecting said organic acid, said organic acid being produced by said bacterium or extract thereof. 
     
     
         2 . The method according to  claim 1 , said method comprising:
 a) culturing and/or growing said bacterium in contact with vegetal biomass under aerobic and/or anaerobic conditions; and   b) collecting at least one organic acid.   
     
     
         3 . The method according to  claim 2 , wherein steps a) and b) are carried out simultaneously or sequentially. 
     
     
         4 . The method according to  claim 1 , wherein the vegetal biomass is wood, wood residue, forest residue, mill residue, agricultural crop, agricultural residue, an edible and/or non-edible plant or parts thereof, straw, garden waste, an aquatic plant, manure, organic municipal wastes, industrial organic wastes and/or biodegradable wastes. 
     
     
         5 . The method according to  claim 1 , wherein the vegetal biomass further comprises lignin, glucuronoxylan, arabinoxylan, glucomannan, xyloglucan, starch, sucrose, lactose, maltose trehalose, glucose, xylose, mannose, arabinose, rhamnose, galactose and/or fructose. 
     
     
         6 . The method according to  claim 1 , wherein said bacterium is viable in the presence of toxic agents or organic solvents. 
     
     
         7 . The method according to  claim 1 , wherein said bacterium is grown in a temperature range from approximately 40 to 70° C. 
     
     
         8 . The method according to  claim 1 , wherein said bacterium is viable or used in a pH interval between approximately 3 and 9.5. 
     
     
         9 . The method according to  claim 1 , wherein said  Deinococcus  bacterium is able to convert C6 and/or C5 sugars and/or to promote the digestion of cellulose to generate glucose and/or to promote the digestion of hemicellulose to generate xylose. 
     
     
         10 . The method according to  claim 1 , wherein said bacterium is  Deinococcus geothermalis  or  Deinococcus murrayi.    
     
     
         11 . The method according to  claim 1 , wherein said bacterium is  Deinococcus geothermalis.    
     
     
         12 . The method according to  claim 1 , wherein a reactor for the conversion of vegetal biomass is employed. 
     
     
         13 . The method according to  claim 1 , wherein the organic acid is selected from the group consisting of acetic acid, propionic acid, pyruvic acid, butyric acid, lactic acid, succinic acid, salts of said acids and mixtures thereof. 
     
     
         14 . The method according to  claim 1 , said method comprising:
 a) culturing and/or growing said bacterium with a liquid culture medium containing vegetal biomass under aerobic and/or anaerobic conditions; and   b) separating at least one organic acid from the liquid culture medium.