Process for producing polyester, process for producing substituted a-hydroxy acid, and clostridium beijerinckii strain hica432

Abstract

A process for producing a polyester, the process comprising the steps of (1) fermenting a saccharide with a microorganism to obtain at least one substituted α-hydroxy acid represented by the formula: HO—CHR—COOH (wherein R represents a hydrocarbon group having 1 to 10 carbon atoms), and (2) polymerizing the substituted α-hydroxy acid or a derivative thereof.

What is claimed is:  
     
         1 . A process for producing a polyester, comprising the steps of: 
 (1) fermenting a saccharide with a microorganism to obtain at least one substituted α-hydroxy acid represented by the formula:    HO—CHR—COOH    wherein R represents a hydrocarbon group having 1 to 10 carbon atoms; and    (2) polymerizing the substituted α-hydroxy acid or a derivative thereof.    
     
     
         2 . The process for producing a polyester according to  claim 1 , wherein said saccharide is glucose or xylose.  
     
     
         3 . The process for producing a polyester according to  claim 2 , which further comprises, prior to the steps (1) and (2), the step of (3) subjecting a raw material containing cellulose or hemicellulose, to hydrolysis to obtain the glucose or xylose.  
     
     
         4 . The process for producing a polyester according to  claim 1 , wherein said saccharide is starch.  
     
     
         5 . The process for producing a polyester according to  claim 1 , wherein said saccharide is starch or glucose, and said at least one substituted α-hydroxy acid is selected from the group consisting of lactic acid (the R is a methyl group), β-phenyllactic acid (the R is a benzyl group) and 2-hydroxyisocaproic acid (the R is an isobutyl group).  
     
     
         6 . The process for producing a polyester according to  claim 1 , wherein said at least one substituted α-hydroxy acid contains at least β-phenyllactic acid (the R is a benzyl group).  
     
     
         7 . The process for producing a polyester according to  claim 1 , wherein said at least one substituted α-hydroxy acid contains at least 2-hydroxyisocaproic acid (the R is an isobutyl group).  
     
     
         8 . The process for producing a polyester according to  claim 1 , wherein said saccharide is xylose, and said at least one substituted α-hydroxy acid is at leas one of β-phenyllactic acid (the R is a benzyl group) and 2-hydroxyisocaproic acid (the R is an isobutyl group).  
     
     
         9 . The process for producing a polyester according to  claim 1 , wherein said microorganism used in the step (1) is an anaerobic bacterium.  
     
     
         10 . The process for producing a polyester according to  claim 9 , wherein the fermentation in the step (1) is carried out in the presence of pyruvic acid.  
     
     
         11 . The process for producing a polyester according to  claim 9 , wherein said anaerobic bacterium is a bacterium belonging to the genus Clostridium.  
     
     
         12 . The process for producing a polyester according to  claim 11 , wherein said bacterium belonging to the genus Clostridium is Clostridium beijerinckii strain HICA432, FERMP-18373.  
     
     
         13 . The process for producing a polyester according to  claim 1 , wherein said substituted α-hydroxy acid is a cyclic dimer lactide, and which process further comprises, prior to the step-(2) polymerization, the step of (4) dehydrating the substituted α-hydroxy acid by two molecules to effect cyclic diesterification to obtain the cyclic dimer lactide.  
     
     
         14 . The process for producing a polyester according to  claim 1 , wherein said polyester contains at lest one of repeating units represented by the following Formulas (I) to (III).  
       
         
           
           
               
               
           
         
       
     
     
         15 . A process for producing a substituted α-hydroxy acid, comprising fermenting a saccharide with a microorganism.  
     
     
         16 . The process for producing a substituted α-hydroxy acid according to  claim 15 , wherein said microorganism is an anaerobic bacterium.  
     
     
         17 . The process for producing a substituted α-hydroxy acid according to  claim 16 , wherein the step of obtaining said substituted α-hydroxy acid is carried out by fermentation with an anaerobic bacterium in the presence of pyruvic acid.  
     
     
         18 . The process for producing a substituted α-hydroxy acid according to  claim 16 , wherein said anaerobic bacterium is a bacterium belonging to the genus Clostridium.  
     
     
         19 . The process for producing a substituted α-hydroxy acid according to  claim 18 , wherein said bacterium belonging to the genus Clostridium is  Clostridium beijerinckii  strain HICA432, FERMP-18373.  
     
     
         20 . A  Clostridium beijerinckii  strain HICA432, FERMP-18373.  
     
     
         21 . A  Clostridium beijerinckii  strain HICA432, FERMP-18373, used to form a substituted α-hydroxy acid  
       from a saccharide.