Algal medium chain length fatty acids and hydrocarbons

Abstract

The present invention provides methods and compositions for production of algal-based medium chain fatty acids and hydrocarbons. More specifically, the invention relates to a Nannochloropsis algal strain and mutants that produces high amounts of C16 fatty acids and hydrocarbons. The present invention provides methods and compositions for production of algal-based medium chain fatty acids and hydrocarbons. More specifically, the invention relates to a Nannochloropsis algal strain and mutants that produces high amounts of C16 fatty acids and hydrocarbons.

1 . A method for producing algal medium chain length fatty acids or hydrocarbons, comprising:
 culturing a first algal strain wherein the first algal strain produces a first medium chain length fatty acid subset wherein at least about 50% of the fatty acids in the subset are of a chain length of C16, wherein the culturing is conducted under conditions suitable to promote the production of the first medium chain length fatty acid subset; and   extracting oil from the first algal strain to produce a medium chain length combination;   wherein the medium chain length combination comprises carbon chain length C10, C12, C14 and C16 fatty acids or hydrocarbons, wherein said oil is enriched for C16 fatty acids such that at least about 50% of the fatty acids in said oil are C16 fatty acids.   
     
     
         2 . The method of  claim 1  wherein the medium chain length fatty acid subset comprises at least about 60% C16 fatty acids. 
     
     
         3 . The method of  claim 1 , wherein the first algal strain is selected from the group consisting of  Nannochloropsis  strain LARB-AZ 0202.0 (ATCC Deposit Number PTA-11048), LARB-AZ 0202.2 (ATCC Deposit Number PTA 11049), LARB-AZ 0202.3 (ATCC Deposit Number PTA-11050),  Nannochloropsis  sp.,  Pinguiococcus pyrenoidosus, Aphanocapsa  sp.,  Biddulphia aurita, Crypthecodinium  sp.,  Emiliania huxleyi, Nitzschia alba, Prymnesiumparvum, Skeletonema costatum,  and  Trichodesmium erythraeum.    
     
     
         4 . The method of  claim 1  further comprising co-culturing or separately culturing a second algal strain selected from the group consisting of  Nannochloropsis  strain LARB-AZ 0202.0 (ATCC Deposit Number PTA-11048), LARB-AZ 0202.2 (ATCC Deposit Number PTA 11049), LARB-AZ 0202.3 (ATCC Deposit Number PTA-11050),  Nannochloropsis  sp.,  Pinguiococcus pyrenoidosus, Aphanocapsa  sp.,  Biddulphia aurita, Crypthecodinium  sp.,  Emiliania huxleyi, Nitzschia alba, Prymnesiumparvum, Skeletonema costatum,  and  Trichodesmium erythraeum.    
     
     
         5 . The method of  claim 1  further comprising converting oil extracted from the first algal strain into a hydrocarbon fraction and refining the hydrocarbon fraction to produce one or more sub-fractions enriched in carbon chain lengths C8, C10, C12, C14, or C16 
     
     
         6 . The method of  claim 1  further comprising culturing one or more further algal strains that produce a second medium chain length fatty acid subset wherein at least about 20% of the fatty acids in said second medium chain length fatty acid subset are medium chain length fatty acids, wherein the culturing is conducted under conditions suitable to promote the production of the second medium chain length fatty acid subset. 
     
     
         7 . The method of  claim 3  wherein the first algal strain and the one or more further algal strains are cultured as separate cultures, or cultured together as a co-culture. 
     
     
         8 . The method of  claim 1 , further comprising producing kerosene from the oil. 
     
     
         9 . The method of  claim 3  further comprising a third algal strain that is different from said first and second algal strains and selected from the group consisting of  Nannochloropsis  strain LARB-AZ 0202.0 (ATCC Deposit Number PTA-11048), LARB-AZ 0202.2 (ATCC Deposit Number PTA 11049), LARB-AZ 0202.3 (ATCC Deposit Number PTA-11050),  Nannochloropsis  sp.,  Pinguiococcus pyrenoidosus, Aphanocapsa  sp.,  Biddulphia aurita, Crypthecodinium  sp.,  Emiliania huxleyi, Nitzschia alba, Prymnesiumparvum, Skeletonema costatum,  and  Trichodesmium erythraeum.    
     
     
         10 . A method for producing algal medium chain length fatty acids or hydrocarbons, comprising:
 culturing one or more of  Nannochloropsis  strain LARB-AZ 0202.0 (ATCC Deposit Number PTA-11048), LARB-AZ 0202.2 (ATCC Deposit Number PTA 11049), LARB-AZ 0202.3 (ATCC Deposit Number PTA-11050), under conditions suitable to promote the production of a first medium chain length fatty acid subset comprising at least about 50% C16 fatty acids or hydrocarbons;   culturing one or more further algal strains under conditions suitable to promote the production of a second medium chain length fatty acid subset comprising at least about 50% C10 or C14 chain length fatty acids or hydrocarbons;   culturing one or more further algal strains under conditions suitable to promote the production of a second medium chain length fatty acid subset comprising at least about 50% C10 or C12 chain length fatty acids or hydrocarbons;   extracting oil from the cultured  Nannochloropsis  strain LARB-AZ 0202.0 or a mutant thereof and the one or more further algal strains to produce a medium chain length combination, wherein the medium chain length combination comprises carbon chain length C16, C14 and one or more of C10 and C12 fatty acids or hydrocarbons.   
     
     
         11 . The method of  claim 10 , further comprising converting the medium chain length combination into a hydrocarbon fraction and further comprising refining the hydrocarbon fraction to produce one or more fractions enriched in medium chain length hydrocarbons, wherein the one or more fractions comprises one or more fractions enriched in carbon chain length C10, C12, C14, and C16 hydrocarbons. 
     
     
         12 . The method of  claim 10  wherein said mutant of  Nannochloropsis  strain LARB-AZ 20202.0 is LARB-AZ 0202.2 (ATCC Deposit Number PTA-11049) or LARB-AZ 0202.3 (ATCC Deposit Number PTA-11050). 
     
     
         13 . The method of  claim 10 , wherein the medium chain length combination is prepared by combining oil extracted from the  Nannochloropsis  strain LARB-AZ 0202.0 or a mutant thereof and the one or more further algal strains after oil extraction or by extracting oil from a culture comprising both the  Nannochloropsis  strain LARB-AZ 0202.0 or a mutant thereof and the one or more further algal strains. 
     
     
         14 . The method of  claim 10  wherein the one or more further algal strains is selected from the group consisting of  Nannochloropsis  strain LARB-AZ 0202.0 (ATCC Deposit Number PTA-11048), LARB-AZ 0202.2 (ATCC Deposit Number PTA 11049), LARB-AZ 0202.3 (ATCC Deposit Number PTA-11050),  Nannochloropsis  sp.,  Pinguiococcus pyrenoidosus, Aphanocapsa  sp.,  Biddulphia aurita, Crypthecodinium  sp.,  Emiliania huxleyi, Nitzschia alba, Prymnesiumparvum, Skeletonema costatum,  and  Trichodesmium erythraeum.    
     
     
         15 . The method of  claim 1  wherein the  Nannochloropsis  strain or mutant thereof is grown in a cell culture that comprises 1.5 g/L NaNO 3  and at a light intensity of about 350 μmol photons m −2  s −1 , and initial N 2  gas concentration of the cell culture of about 0.01 g/L. 
     
     
         16 . The method of  claim 10  wherein the  Nannochloropsis  strain or mutant thereof is grown in a cell culture that comprises 1.5 g/L NaNO 3  and at a light intensity of about 350 μmol photons m −2  s −1 , and initial N 2  gas concentration of the cell culture of about 0.01 g/L. 
     
     
         17 . A composition comprising a  Nannochloropsis  strain LARB-AZ 0202.2 deposited at ATCC Deposit Number PTA-11049 or  Nannochloropsis  strain LARB-AZ 0202.3 deposited at ATCC Deposit Number PTA-11050, or a combination of LARB-AZ 0202.2 and LARB-AZ 0202.3.