# US 2021/0277430 A1 · Fermentation process for the production of lipids > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0277430 A1 - Document ID: US20210277430A1 - Status: Published application - Kind: A1 - Application number: 16/812,967 - Filed: 2020-03-09 - Published: 2021-09-09 - Earliest claimed: 2020-03-09 - Assignees: LanzaTech, Inc. - Applicants: LanzaTech, Inc. - Inventors: Sean Dennis Simpson; Christophe Daniel Mihalcea; Robert John Conrado - Web page: https://patentgrep.com/patent/US20210277430A1 ## CPC - C12P 7/6427: Polyunsaturated fatty acids [PUFA], i.e. having two or more double bonds in their backbone - C12P 7/62: Carboxylic acid esters - C12P 7/6409: Fatty acids - C12P 7/6432: Eicosapentaenoic acids [EPA] - C12P 7/6434: Docosahexenoic acids [DHA] - C12P 7/6463: obtained from glyceride producing microorganisms, e.g. single cell oil - C12P 39/00: Processes involving microorganisms of different genera in the same process, simultaneously - C12P 7/54: Acetic acid (vinegar C12J) - C12P 7/649: Biodiesel, i.e. fatty acid alkyl esters - C12R 2001/01: Bacteria or Actinomycetales {; using bacteria or Actinomycetales} - C12R 2001/89: Algae {; Processes using algae} - 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)} - C12R: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES C12C - C12Q, RELATING TO MICROORGANISMS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract The disclosure provides methods and systems to produce lipid products from a gaseous substrate using a two-stage fermentation process. The method comprises providing a gaseous substrate comprising CO, CO2 or 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. Tail gas from the second bioreactor is recycled to the first bioreactor. ## Claims ### Claim 1 A method for producing at least one lipid product from CO2 and H2, the method comprising: i. receiving a gaseous substrate comprising at least CO2 and H2 in a first bioreactor containing a culture of at least one first microorganism in a first liquid nutrient medium and fermenting the gaseous substrate to produce acetate product in a first fermentation broth; ii. passing at least a portion of the first fermentation broth to a second bioreactor containing a culture of at least one second microorganism in a second liquid nutrient medium, where the second microorganism is not the same as the first microorganism and is selected from Scenedesmus, Thraustochytrium, Japonochytrium, Aplanochytrium, Elina, and Labyrinthula, and fermenting the acetate product to produce at least one lipid product in a second fermentation broth; iii. obtaining a tail gas comprising at least CO2 and O2 from the second bioreactor; and iv. separating at least a portion of the O2 from the tail gas and recycling at least a portion of the reminder of the tail gas to the first bioreactor. ### Claim 2 (depends on 1) The method of claim 1, wherein the production rate of acetate in the first bioreactor is at least 10 g/L/day. ### Claim 3 (depends on 1) The method of claim 1, wherein at least one of the first microorganisms in the first bioreactor is selected from Acetobacterium, Moorella, Clostridium, Pyrococcus, Eubacterium, Desulfobacterium, Carboxydothermus Acetogenium, Acetoanaerobium, Butyribacterium, Peptostreptococcus, Ruminococcus, Oxobacter, and Methanosarcina. ### Claim 4 (depends on 1) The method of claim 1 wherein at least one of the first micoorganisms in the first bioreactor is Acetobacterium woodii. ### Claim 5 (depends on 1) The method of claim 1, wherein the at least one of the second microorganisms in the second bioreactor is Thraustochytrium. ### Claim 6 (depends on 1) The method of claim 1, further comprising producing, from the at least one lipid product, at least one tertiary product selected from hydrogenation-derived renewable diesel, fatty acid methyl esters, fatty acid ethyl esters, and biodiesel. ### Claim 7 (depends on 1) The method of claim 1, further comprising limiting at least one nutrient in the second liquid nutrient medium in the second bioreactor to increase lipid production. ### Claim 8 (depends on 7) The method of claim 7, wherein the limited nutrient is nitrogen. ### Claim 9 (depends on 1) The method of claim 1, wherein the at least one lipid product is a polyunsaturated fatty acid. ### Claim 10 (depends on 9) The method of claim 9, wherein the polyunsaturated fatty acid is an omega-3 fatty acid. ### Claim 11 (depends on 10) The method of claim 10, wherein the omega-3 fatty acid is one or more of alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid. ### Claim 12 (depends on 1) The method of claim 1 wherein the separating of at least a portion of the O2 from the tail gas is accomplished using one or more stages of pressure swing adsorption, membrane separation, scrubbing with a basic solution, absorption using a solvent, or any combination thereof. ### Claim 13 (depends on 1) The method of claim 1 further comprising recycling the O2 from the separation of at least a portion of the O2 from the tail gas to the second bioreactor. ### Claim 14 (depends on 1) The method of claim 1 further comprising recovering a gaseous stream comprising CO2 and H2 from the first bioreactor and recycling the gaseous stream to the first bioreactor. ### Claim 15 (depends on 1) The method of claim 1 further comprising recycling at least a portion of the second fermentation broth to the first bioreactor. ### Claim 16 (depends on 1) The method of claim 1 further comprising removing the first microorganism from the first fermentation broth before passing at least a portion of the first fermentation broth to the second bioreactor and recycling the first microorganism to the first bioreactor. ### Claim 17 (depends on 1) The method of claim 1 further comprising removing the second microorganism from the second fermentation broth and recycling the second microorganism to the second bioreactor. ### Claim 18 (depends on 17) The method of claim 17 further comprising passing, to the first bioreactor, the remainder of the second fermentation broth after removing the second microorganism. ### Claim 19 (depends on 1) The method of claim 1 further comprising generating the H2 using an electrolyzer. ### Claim 20 (depends on 1) The method of claim 1 further comprising generating O2 using an electrolyzer and introducing the electrolyzer-generated O2 to the second bioreactor. ### Claim 21 (depends on 1) The method of claim 1 wherein the second bioreactor is operated in an oxygen limited mode.