Abstract: A method of producing amino acids by fermentation in a bioreactor, wherein the bioreactor includes methanogenic microorganisms in a fermentation broth, the method including at least the step of feeding a gaseous carbon source including carbon dioxide and/or carbon monoxide, a nitrogen source including nitrogen gas and a sulfur source to the bioreactor under conditions such that the methanogenic microorganisms produce the amino acids, wherein the fermentation broth includes ammonium at a concentration of 0.1 mmol/L to 200 mmol/L is disclosed. Preferred methanogenic microorganisms are e.g. archaea selected from Methanothermobacter, Methanothermococcus and Methanococcus.

Abstract: A method of producing amino acids by fermentation in a bioreactor is disclosed, wherein the bioreactor includes methanogenic microorganisms in a fermentation broth, the method including at least the steps of feeding a gaseous carbon source including carbon dioxide and/or carbon monoxide, a nitrogen source and a sulfur source to the bioreactor under conditions such that the methanogenic microorganisms produce the amino acids; and harvesting at least a portion of the amino acids from the supernatant of the fermentation broth. Preferred methanogenic microorganisms are e.g. archaea selected from Methanothermobacter, Methanothermococcus and Methanococcus. Also provided is a fermentation broth comprising methanogenic microorganisms and amino acids in the supernatant, and a bioreactor including the same.

Abstract: A method of producing amino acids by fermentation in a bioreactor is disclosed, wherein the bioreactor includes methanogenic microorganisms in a fermentation broth, the method including at least the step of feeding a gaseous carbon source including carbon dioxide and/or carbon monoxide, a nitrogen source including nitrogen gas and a sulfur source to the bioreactor under conditions such that the methanogenic microorganisms produce the amino acids, wherein the fermentation broth includes ammonium at a concentration of at least 0.1 mmol/L and the tungstate concentration in the fermentation broth is below 0.1 ?mol/L. Preferred methanogenic microorganisms are e.g. archaea selected from Methanothermobacter, Methanothermococcus and Methanococcus. Also provided is a fermentation broth including methanogenic microorganisms, ammonium at a concentration of at least 0.1 mmol/L, wherein the tungstate concentration in the fermentation broth is below 0.1 ?mol/L, and a bioreactor including the same.