ACID PRODUCTION BY FERMENTATION
The invention provides methods for producing Lactate by anaerobic Fermentation. According to particular methods of the invention, Lactate is produced by anaerobic fermentation of a substrate comprising hydrogen and carbon monoxide.
1 - 21 . (canceled)
22 . A method of producing lactate by microbial fermentation, said method comprising:
providing a substrate that includes CO;
in a bioreactor containing a culture of one or more micro-organisms, anaerobically fermenting the substrate to produce lactate.
23 . The method of claim 22 , wherein providing the substrate comprises providing the substrate at a level sufficient to produce lactate.
24 . The method of claim 22 wherein providing the substrate comprises providing the substrate at a level sufficient to maintain a specific CO uptake rate of at least 0.4 mmol CO/gram dry cells weight of bacteria/minute by the culture.
25 . The method of claim 24 , wherein providing the substrate comprises providing the substrate at a level sufficient to maintain a specific CO uptake rate of at least 0.6 mmol CO/g/min.
26 . The method of claim 22
wherein one or more of the one or more micro-organisms includes one or more lactate dehydrogenase genes, and
wherein the method further includes upregulating the lactate dehydrogenase gene(s), such that lactate is produced by the micro-organism(s).
27 . The method of claim 26 , wherein providing the substrate comprises providing the substrate at a level sufficient to produce lactate.
28 . The method of claim 26 , wherein providing a substrate that includes CO comprises providing the substrate at a level sufficient to maintain a specific rate of CO uptake of at least 0.4 mmol CO/gram dry cells weight of bacteria/minute by the culture.
29 . The method of claim 22 wherein the one or more micro-organism(s) comprise Clostridium autoethanogenum.
30 . The method of claim 22 wherein providing a substrate that contains CO comprises providing a gaseous substrate.
31 . The method of claim 30 , wherein providing a gaseous substrate comprises providing a gaseous substrate that contains at least about 15% to about 100% CO by volume.
32 . The method of claim 30 , wherein providing a gaseous substrate that includes CO comprises providing gas obtained as a by-product from an industrial process.
33 . A method of producing lactate by microbial fermentation, the method including:
providing a substrate
in a bioreactor that contains a culture having Clostridium autoethanogenum , anaerobically fermenting the substrate to produce lactate.
34 . The method of claim 33 , wherein providing a substrate comprises providing a substrate that includes one or more carbohydrates.
35 . The method of claim 34 , wherein the method further comprises providing a substrate that includes CO before, at the same time, or after the step of providing a substrate comprising one or more carbohydrates.
36 . The method of claim 35 , wherein the method further comprises alternating between providing a substrate comprising CO and providing a substrate comprising one or more carbohydrates.