# US 2014/0154755 A1 · Fermentation process > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0154755 A1 - Document ID: US20140154755A1 - Status: Published application - Kind: A1 - Application number: 14/093,249 - Filed: 2013-11-29 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Lanzatech New Zealand Limited - Applicants: LanzaTech New Zealand Limited - Inventors: Sean Dennis Simpson; Sebastian Michal Bernasek - Web page: https://patentgrep.com/patent/US20140154755A1 ## CPC - C12P 7/54: Acetic acid (vinegar C12J) - C12P 7/6463: obtained from glyceride producing microorganisms, e.g. single cell oil - C12P 7/649: Biodiesel, i.e. fatty acid alkyl esters - G01N 33/92: involving lipids, e.g. cholesterol {, lipoproteins, or their receptors (steroid hormones G01N33/743)} - Y02E 50/10: Biofuels, e.g. bio-diesel - C12P: FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE {(brewing of beer C12C; producing vinegar C12J; producing specific peptides or proteins C07K; producing enzymes C12N9/00; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification C12N15/00; measuring or testing processes involving enzymes or microorganisms C12Q; measuring or testing processes involving nucleic acid amplification reactions C12Q1/6844; fermentation processes to form a food composition, A21 or A23; compounds in general, see the relevant compound class, e.g. C01, C07)} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract The invention provides methods and systems for the production of lipid products from a gaseous substrate using a two stage fermentation process. The method comprises providing a gaseous substrate comprising CO or CO2 and H2 or mixtures thereof, to a first bioreactor containing a culture or one or more microorganisms, and fermenting the substrate to produce acetate. The acetate from the first bioreactor is then provided to a second bioreactor, where it is used as a substrate for fermentation to lipids by one or more microalgae. ## Claims ### Claim 1 A method for producing at least one lipid product from a gaseous substrate, the method comprising: a) receiving a gaseous substrate in a first bioreactor comprising a culture of at least one microorganism in a liquid nutrient medium, and fermenting the gaseous substrate to produce a product selected from an acid or an acid and an alcohol; and b) passing at least a portion of the acid product to a second bioreactor comprising a culture of at least one microalgae in a liquid nutrient medium, and fermenting the acid to produce at least one lipid product. ### Claim 2 (depends on 1) The method of claim 1, wherein the gaseous substrate comprises CO or CO2 and H2, or mixtures thereof. ### Claim 3 (depends on 1) The method of claim 1, wherein the at least one acid is selected from the group consisting of acetate, butyrate, succinate, lactate and propionate. ### Claim 4 (depends on 1) The method of claim 1, wherein the acid is acetate, and the production rate of acetate in the first bioreactor is at least 10 g/L/day. ### Claim 5 (depends on 1) The method of claim 1, wherein the at least one alcohol are selected from the group consisting of ethanol, butanol, methanol, propanol and mixtures thereof. ### Claim 6 (depends on 1) The method of claim 1, wherein the at least one microorganism in the first bioreactor is selected from the group consisting of Acetobacterium, Moorella, Clostridium, Pyrococcus, Eubacterium, Desulfobacterium, Carboxydothermus Acetogenium, Acetoanaerobium, Butyribacterium, Peptostreptococcus, Ruminococcus, Oxobacter, and Methanosarcina. ### Claim 7 (depends on 1) The method of claim 1, wherein the at least one microalgae in the second bioreactor is selected from the group consisting of Chlorella, Chlamamydomonas, Dunaliella, Euglena, Parvum, Tetraselmis, Porphyridium, Spirulina, Synechoccus, Anabaena, Schizochytrium, Botyrococcus, Fucus, Parachlorella, Pseudochlorella, Brateococcus, Prototheca and Scenedesmus. ### Claim 8 (depends on 1) The method of claim 1, wherein the at least one lipid product is used to produce at least one tertiary product selected from the group consisting of hydrogenation-derived renewable diesel (HDRD), fatty acid methyl esters (FAME), fatty acid ethyl esters (FAEE) and biodiesel. ### Claim 9 (depends on 1) The method of claim 1, wherein lipid production is increased in the second bioreactor by substantially limiting at least one nutrient in the liquid nutrient medium. ### Claim 10 (depends on 9) The method of claim 9, wherein the limited nutrient is nitrogen. ### Claim 11 A method for controlling pH in a fermentation process, the method comprising: a) passing a gaseous substrate comprising CO or CO2 and H2, or mixtures thereof to a first bioreactor comprising a culture of at least one microorganism in a liquid nutrient medium, and fermenting the gaseous substrate to produce a broth comprising a product selected from at least one acid or at least one acid and at least one alcohol; b) passing at least a portion of the broth comprising the product to a second bioreactor comprising a culture of at least one microalgae in a liquid nutrient medium, and fermenting the acid to produce at least one lipid product; and c) recycling at least a portion of the broth from the second reactor back to the first bioreactor, wherein the acid concentration in the recycled broth is substantially reduced. ### Claim 12 (depends on 11) The method of claim 11, wherein the pH in the first bioreactor is maintained between pH 4.5 to 6. ### Claim 13 (depends on 11) The method of claim 11, wherein the acid is selected from the group consisting of acetate, butyrate, succinate, lactate and propionate. ### Claim 14 (depends on 11) The method of claim 11, wherein the acid is acetate and wherein the production rate of acetate in the first bioreactor is at least 10 g/L/day. ### Claim 15 (depends on 11) The method of claim 11, wherein the at least one alcohol is selected from the group consisting of ethanol, butanol, methanol, and propanol. ### Claim 16 (depends on 11) The method of claim 11, wherein the at least one microorganism in the first bioreactor is selected from the group consisting of Acetobacterium, Moorella, Clostridium, Pyrococcus, Eubacterium, Desulfobacterium, Carboxydothermus Acetogenium, Acetoanaerobium, Butyribacterium, Peptostreptococcus, Ruminococcus, Oxobacter, and Methanosarcina. ### Claim 17 (depends on 11) The method of claim 11, wherein the at least one microalgae in the second bioreactor is selected from the group comprising Chlorella, Chlamamydomonas, Dunaliella, Euglena, Parvum, Tetraselmis, Porphyridium, Spirulina, Synechoccus, Anabaena, Schizochytrium, Botyrococcus, Fucus, Parachlorella, Pseudochlorella, Brateococcus, Prototheca and Scenedesmus. ### Claim 18 (depends on 11) The method of claim 11, wherein the at least one lipid product is used to produce at least one tertiary product selected from the group comprising FAME, FAEE, HDRD and biodiesel. ### Claim 19 (depends on 11) The method of claim 11, wherein the lipid production is increased in the second bioreactor by substantially limiting at least one nutrient in the liquid nutrient medium. ### Claim 20 (depends on 19) The method of claim 19, wherein the limited nutrient is nitrogen. ### Claim 21 (depends on 11) The method of claim 11, further comprising first treating the both from step (c) to remove substantially all biomass prior to recycling the broth to the first bioreactor. ### Claim 22 (depends on 11) The method of claim 11, further comprising first passing the broth from step (c) through an oxygen scrubbing module prior to recycling the broth to the first bioreactor.