Provided are a method for producing an organic substance and an apparatus for producing an organic substance that are capable of efficiently cooling a synthesis gas and converting the synthesis gas to an organic substance at a high conversion efficiency using a microbial catalyst. A method for producing an organic substance includes a step of passing a synthesis gas G1 discharged from a gasifier 2 through a heat exchanger 20 to cool the synthesis gas G1, a step of passing the synthesis gas G1 cooled with the heat exchanger 20 through a gas cooling tower 21 to cool the synthesis gas G1 with water sprayed in the gas cooling tower 21 and a step of bringing the synthesis gas G1 that has passed through at least the heat exchanger 20 and the gas cooling tower 21 into contact with a microbial catalyst to generate an organic substance.

Chemically defined culture medium and culture conditions that allow bacteria to assimilate dinitrogen gas (N.sub.2) as a nitrogen source during bio-ethanol production are disclosed herein. Methods of bioethanol production using the chemically defined culture medium and culture conditions are also disclosed.

Provided is a method for producing an organic substance from a syngas by microbial fermentation, wherein only the solid component can be efficiently separated from an organic substance-containing liquid obtained by microbial fermentation to reduce the content of microorganisms, etc. Disclosed is a method for producing an organic substance from a syngas containing carbon monoxide by microbial fermentation, which comprises a microbial fermentation step wherein the syngas is fed to a microbial fermenting vessel and a liquid containing an organic substance is obtained by microbial fermentation, a solid-liquid separation step wherein the organic substance-containing liquid is separated into a solid component containing microorganisms and a liquid component containing an organic substance, and an extraction step wherein the organic substance-containing liquid is extracted from the liquid component, wherein the organic substance-containing liquid is heated to 40° C. or higher and then subjected to a centrifugal separation operation.

Provided herein are methods for generating cellular biomass in continuous aerobic fermentation systems. The biomass yield, and the concentration of polyhydroxyalkanoate within the biomass, are each directed to advantageous levels by operating the continuous fermentation system under particular nutrient limitation conditions. Also provided are biomass produced using the provided methods, and animal feed compositions including the provided biomass.

A transformant obtained by introducing a DNA of (a1), (a2), or (a3) below, and (b) an alcohol dehydrogenase gene, into a bacterium of the genus Hydrogenophilus, can efficiently produce isobutanol utilizing carbon dioxide as a sole carbon source. (a1) DNA which consists of a base sequence of SEQ ID NO: 1; (a2) DNA which consists of a base sequence having 90% or more identity with SEQ ID NO: 1, the DNA encoding a polypeptide having 2-keto-acid decarboxylase activity; (a3) DNA which hybridizes with a DNA consisting of a base sequence complementary to SEQ ID NO: 1 under stringent conditions, and which encodes a polypeptide having 2-keto-acid decarboxylase activity.

Provided is a method of producing a product by culturing a carboxydotrophic acetogenic bacterium with a disrupting mutation in a lactate dehydrogenase enzyme in the presence of a substrate comprising CO, CO.sub.2, and/or H.sub.2. Preferably, the disrupting mutation reduces or eliminates the expression or activity of the enzyme such that the bacterium produces a reduced amount of lactate or no lactate.

Device and process for the conversion of a feedstock of aromatic compounds, in which the feedstock is treated notably by means of a fractionation train (4-7), a xylene separation unit (10) and an isomerization unit (11), and in which a pyrolysis unit (13) treats a second hydrocarbon feedstock, produces a pyrolysis effluent feeding the feedstock, and produces a pyrolysis gas comprising CO, CO.sub.2 and H.sub.2; a reverse water gas shift RWGS reaction section (50) treats the pyrolysis gas and produces an RWGS gas enriched in CO and in water; a fermentation reaction section (52) treats the RWGS gas enriched in CO and in water, to produce ethanol and recycle the ethanol to the inlet of the pyrolysis unit.

A system for producing an organic substance, including: a synthesis gas generation furnace for producing a synthesis gas by partially oxidizing a waste including a carbon source; a synthesis gas purification unit connected to the synthesis gas generation furnace and purifying the synthesis gas generated in the synthesis gas generation furnace to reduce an impurity concentration in the synthesis gas; and an organic substance synthesis unit which is connected to the synthesis gas purification unit and generates an organic substance from the synthesis gas purified in the synthesis gas purification unit, wherein the synthesis gas purification unit includes a detection unit for measuring an impurity concentration in the synthesis gas.

The present invention provides methods and compositions for increasing lignin degradation to produce a biological product. Also provided are methods for increasing expression of laccase in a bacterial species to produce increased lignin degradation. Also provided are bacterial cells and commodities or commodity produces produced from such methods.

Provided is a method which enables efficient separation of a component such as microorganisms from an organic substance-containing liquid obtained by microbial fermentation. Disclosed is a method for producing an organic substance comprising a microbial fermentation step of obtaining an organic substance-containing liquid and a separation step of heating the organic substance-containing liquid and separating into a liquid or solid component containing microorganisms and a gaseous component containing the organic substance.