Abstract: Lactic acid is obtained by a method including (A) a step of continuous fermentation wherein a fermentation culture medium of a microorganism having an ability of lactic acid fermentation is filtered through a porous membrane having an average pore size of not less than 0.01 ?m and less than 1 ?m with a transmembrane pressure difference within the range of 0.1 to 20 kPa, and the permeate is collected, while retaining the non-permeated liquid in or returning the non-permeated liquid to the culture, and adding a fermentation feedstock to the culture; (B) a step of filtering the permeate obtained in Step (A) through a nanofiltration membrane; and (C) a step of distilling the permeate obtained in Step (B) under a pressure of not less than 1 Pa and not more than atmospheric pressure, at 25° C. to 200° C. to recover lactic acid.

Abstract: Lactic acid is obtained by a method including (A) a step of continuous fermentation wherein a fermentation culture medium of a microorganism having an ability of lactic acid fermentation is filtered through a porous membrane having an average pore size of not less than 0.01 ?m and less than 1 ?m with a transmembrane pressure difference within the range of 0.1 to 20 kPa, and the permeate is collected, while retaining the non-permeated liquid in or returning the non-permeated liquid to the culture, and adding a fermentation feedstock to the culture; (B) a step of filtering the permeate obtained in Step (A) through a nanofiltration membrane; and (C) a step of distilling the permeate obtained in Step (B) under a pressure of not less than 1 Pa and not more than atmospheric pressure, at 25° C. to 200° C. to recover lactic acid.

Abstract: Lactic acid is obtained by a method including (A) a step of continuous fermentation wherein a fermentation culture medium of a microorganism having an ability of lactic acid fermentation is filtered through a porous membrane having an average pore size of not less than 0.01 ?m and less than 1 ?m with a transmembrane pressure difference within the range of 0.1 to 20 kPa, and the permeate is collected, while retaining the non-permeated liquid in or returning the non-permeated liquid to the culture, and adding a fermentation feedstock to the culture; (B) a step of filtering the permeate obtained in Step (A) through a nanofiltration membrane; and (C) a step of distilling the permeate obtained in Step (B) under a pressure of not less than 1 Pa and not more than atmospheric pressure, at 25° C. to 200° C. to recover lactic acid.

Abstract: A method of producing a chemical product includes cultivating microorganisms or culture cells in a fermentation tank; transferring a culture liquid from the fermentation tank to a membrane separation tank to filter the culture liquid through a separation membrane; and collecting a fermentation product from a filtration liquid as the chemical product while refluxing an unfiltered culture liquid that has not been filtered to be joined to the culture liquid on an upstream side of the membrane separation tank, wherein one portion of the culture liquid to be transferred from the fermentation tank is allowed to bypass the membrane separation tank depending on a pressure at a culture liquid flow-in side of the membrane separation tank.

Abstract: A method of producing a sugar liquid using a cellulose-containing biomass as a raw material includes (a) hydrolyzing a cellulose-containing biomass to produce an aqueous sugar solution and (b) filtering the obtained aqueous sugar solution through a reverse osmosis membrane to collect a purified sugar liquid from a feed side, while removing fermentation-inhibiting substances from a permeate side.

Abstract: A method of producing a chemical includes culturing cells in a culture solution in a fermentor to ferment a feedstock to produce a chemical; supplying the culture solution containing the chemical produced in the culturing to a plurality of separation membrane units arranged in parallel; filtering the culture solution supplied in the supplying to separate a permeate containing the chemical; refluxing a retentate that is not filtered in the filtering to the fermentor; and supplying a gas containing oxygen to the plurality of separation membrane units while a supply amount is changed to at least two different values to perform scrubbing, wherein the supply amount and supply time of the gas containing oxygen supplied in the culturing and the supplying the gas are set so that a kLa value is within a predetermined range from an optimal kLa value for the cells cultured in the culturing.

Abstract: The invention provides a method of producing a chemical product through continuous fermentation which includes filtering a culture of a microorganism or cultured cells with a separation membrane to recover a product from a filtrate and simultaneously retaining a nonfiltered fluid in, or refluxing it to, the culture, and adding fermentation materials to the culture, wherein a porous membrane having an average pore size of 0.01 ?m or more to less than 1 ?m is used as the separation membrane and the filtration is conducted with a transmembrane pressure difference in the range of 0.1 to 20 kPa. According to this method, the fermentation productivity of the chemical product can be largely elevated at high stability and a low cost.

Abstract: A method of producing a chemical product includes cultivating microorganisms or culture cells in a fermentation tank; transferring a culture liquid from the fermentation tank to a membrane separation tank to filter the culture liquid through a separation membrane; and collecting a fermentation product from a filtration liquid as the chemical product while refluxing an unfiltered culture liquid that has not been filtered to be joined to the culture liquid on an upstream side of the membrane separation tank, wherein one portion of the culture liquid to be transferred from the fermentation tank is allowed to bypass the membrane separation tank depending on a pressure at a culture liquid flow-in side of the membrane separation tank.

Abstract: A method produces cadaverine more efficiently and at a higher yield than production methods by the conventional fermentation methods. The method includes culturing coryneform bacterium/bacteria having an ability to produce cadaverine and having a resistance to 2,2?-thiobis(ethylamine). Preferably, the coryneform bacterium/bacteria has/have lysine decarboxylase activity and, preferably, the coryneform bacterium/bacteria has/have homoserine auxotrophy and/or a resistance to S-(2-aminoethyl)-L-cysteine.

Abstract: A method for producing a diol or triol, which has a step of removing impurities contained in a diol- or triol-containing solution, is provided. In the method, a diol- or triol-containing solution is filtered through a nanofiltration membrane having a polyamide-containing functional layer. The diol- or triol-containing solution is then collected from the permeate flow of the nanofiltration membrane.

Abstract: A method of producing cadaverine is more efficient and at a higher yield than production methods by the conventional fermentation methods. The method includes culturing coryneform bacterium/bacteria having a resistance to a pH of 5.5 or less. Preferably, the coryneform bacterium/bacteria has/have lysine decarboxylase activity and, preferably, the coryneform bacterium/bacteria has/have homoserine auxotrophy and/or a resistance to S-(2-aminoethyl)-L-cysteine.

Abstract: A method of producing a chemical includes culturing cells in a culture solution in a fermentor to ferment a feedstock to produce a chemical; supplying the culture solution containing the chemical produced in the culturing to a plurality of separation membrane units arranged in parallel; filtering the culture solution supplied in the supplying to separate a permeate containing the chemical; refluxing a retentate that is not filtered in the filtering to the fermentor; and supplying a gas containing oxygen to the plurality of separation membrane units while a supply amount is changed to at least two different values to perform scrubbing, wherein the supply amount and supply time of the gas containing oxygen supplied in the culturing and the supplying the gas are set so that a kLa value is within a predetermined range from an optimal kLa value for the cells cultured in the culturing.

Abstract: By a method for producing cadaverine by culturing a microorganism that extracellularly secretes lysine decarboxylase, by-production of lysine is suppressed, the yield of cadaverine relative to glucose consumption is improved compared to conventional production methods, and further, the load on the purification step in purification of cadaverine as a raw material for polyamide can be reduced.

Abstract: A gene expressing cassette codes lactate dehydrogenase that is needed for prevention of deterioration in lactic acid yield and lactic acid production rate in continuous culture with simultaneous filtration of a yeast strain having a lactic acid-producing ability, which achieves high optical purity, high lactic acid yield and high lactic acid production rate simultaneously, a yeast strain having the cassette and a method of producing lactic acid by culturing the yeast strain. The lactate dehydrogenase-expressing cassette is a lactate dehydrogenase-expressing cassette, comprising a gene coding lactate dehydrogenase connected to a site downstream of a promoter, the promoter being a promoter of a gene showing a gene expression amount larger by 5 times or more than the average relative expression amount of all genes after 50 hours from start of culture in continuous culture with simultaneous filtration of a yeast strain having a lactic acid-producing ability.

Abstract: A method of producing a sugar liquid using a cellulose-containing biomass as a raw material includes (a) hydrolyzing a cellulose-containing biomass to produce an aqueous sugar solution and (b) filtering the obtained aqueous sugar solution through a reverse osmosis membrane to collect a purified sugar liquid from a feed side, while removing fermentation-inhibiting substances from a permeate side.

Abstract: Highly productive D-lactic acid fermentation uses a transformant obtained by introducing into a host cell a polynucleotide encoding a polypeptide according to any one of the following (A) to (C) in such a manner that the polypeptide is expressed, which polypeptide has a D-lactate dehydrogenase activity higher than those of conventional polypeptides: (A) a polypeptide having the amino acid sequence shown in SEQ ID NO:1 or 2; (B) a polypeptide having the same amino acid sequence as shown in SEQ ID NO:1 or 2 except that one or several amino acids are substituted, deleted, inserted and/or added, which polypeptide has a D-lactate dehydrogenase activity; and (C) a polypeptide having an amino acid sequence which has a sequence identity of not less than 80% to the amino acid sequence shown in SEQ ID NO:1 or 2, which polypeptide has a D-lactate dehydrogenase activity.

Abstract: A sugar liquid containing only very small amounts of fermentation-inhibiting substances is produced by a method for producing a sugar liquid using a cellulose-containing biomass as a raw material, the method including: (1) a step of hydrolyzing a cellulose-containing biomass to produce an aqueous sugar solution; and (2) a step of filtering the obtained aqueous sugar solution through a nanofiltration membrane and/or reverse osmosis membrane to collect a purified sugar liquid from the feed side, while removing fermentation-inhibiting substances from the permeate side.

Abstract: A method of producing lactic acid by separating lactic acid produced in a culture solution by microbial fermentation, comprising: a step (A) of filtering the culture solution through a nano-filtration membrane; and a step (B) of distilling a lactic-acid-containing solution produced in step (A) under a pressure of 1 Pa to atmospheric pressure (inclusive) at a temperature of 25 to 200° C. (inclusive) to recover lactic acid.

Abstract: A method for producing D-lactic acid in high yield, and to provide a method for producing D-lactic acid with high selectivity, in which optical purity is high and a by-product organic acid is small. In one aspect, a microorganism, wherein activity of pyruvate formate-lyase (pfl) is inactivated or decreased, and further activity of Escherichia coli-derived NADH-dependent D-lactate dehydrogenase (ldhA) is enhanced, is cultured to efficiently produce D-lactic acid. With regard to a method for enhancing ldhA activity, by linking, on a genome, a gene encoding ldhA with a promoter of a gene which controls expression of a protein involved in a glycolytic pathway, a nucleic acid biosynthesis pathway or an amino acid biosynthesis pathway, suitable results are obtained compared to the method for enhancing expression of the gene using an expression vector.

Abstract: A method of producing lactic acid by continuous fermentation includes filtering a culture of polyploidy prototrophic yeast having a capacity to produce lactic acid by introduction of a lactate dehydrogenase gene through a porous membrane having an average pore size of not less than 0.01 ?m and less than 1 ?m; and recovering the lactic acid from filtrate while the unfiltered liquid is retained in or returned to the culture and a fermentation feedstock is added to the culture.