Abstract: The present invention provides a method for preparing nylon salt, which comprises mixing 1,5-pentanediamine, water and dicarboxylic acid at a temperature of 65 to 120° C. to obtain a nylon salt, wherein the amount of the water is 2% to 12% by weight based on the total weight of the 1,5-pentanediamine and the dicarboxylic acid. The present invention also provides a nylon salt. According to the present method for preparing nylon salt, the incomplete reaction between the 1,5-pentanediamine and the dicarboxylic acid, which is caused by the nylon salt present during the preparation in a solid state, can be avoided; the reaction between the 1,5-pentanediamine and the dicarboxylic acid can be significantly speeded up, and the reaction time is accordingly shorten. Consequently, the content of diamine and dicarboxylic acid remained in the resulting nylon salt is very low. In addition, the final nylon salt product, which present in a solid state, makes it easier to be stored and transported.

Abstract: The expression plasmid vectors comprise a polynucleotide sequence encoding Ldc2 polypeptide, a fragment, and/or a mutant. A backbone plasmid is capable of autonomous replication in a host cell. The host cell is not a P. aeruginosa cell. Transformants are transformed with expression plasmid vector. The transformants are not P. aeruginosa. Mutant host cells comprise a polynucleotide sequence encoding Ldc2 polypeptide, a fragment and/or a mutant that has been integrated into the host cell chromosome. A polypeptide, a fragment and/or a mutant comprise Ldc2. A non-naturally occurring polynucleotide, and/or a mutant encodes polypeptide comprising Ldc2. Biobased cadaverine is produced using the transformants and the biobased cadaverine is prepared by the method. Polyamides are formed using the biobased cadaverine and compositions.

Abstract: The present invention relates to a method for the purification of cadaverine from an aqueous cadaverine salt composition comprising one or more involatile impurities, the method comprising: (1) mixing the aqueous cadaverine salt composition with one or more bases selected from the group consisting of Ca(OH)2, Mg(OH)2, CaO and MgO to provide an aqueous cadaverine composition; and (2) distilling or evaporating the aqueous cadaverine composition to produce purified cadaverine; wherein one or more solvents are added to the evaporation/distillation system before the evaporation/distillation stops, and the one or more solvents comprise at least one or more high boiling point (HBP) solvents.

Abstract: One aspect of the invention relates to a method for the purification of cadaverine from an aqueous cadaverine composition comprising one or more involatile impurities, the method comprising: a) distilling or evaporating the aqueous cadaverine composition wherein one or more solvents are added to the evaporation/distillation system before the evaporation/distillation starts, during the evaporation/distillation and/or after the evaporation/distillation substantially stops when no more evaporation/distillation is observed to produce purified cadaverine, wherein the evaporation or distillation is done at a heating temperature of about 80° C. to about 180° C. and under a pressure of 1 atm or lower, and the one or more solvents comprise at least one or more high boiling point (HBP) solvents having a boiling point of at least about 185° C. (1 atm); and b) recovering the one or more HBP solvents.

Abstract: Disclosed is a process for treating a reaction solution containing a long chain dicarboxylate. The process is characterized by comprising: acidifying a reaction solution so as to convert the long chain dicarboxylate into a long chain dicarboxylic acid, adding an extractant so as to extract the resulting long chain dicarboxylic acid, separating the phase rich in the long chain dicarboxylic acid, and further separating the long chain dicarboxylic acid. The process of the present invention has the following advantages: 1) the processing route is simple, the operation time is short, less equipment is required, and the production efficiency is high; 2) product yield is high; 3) product quality is good, purity in the resulting products is high, and the color is lighter; and 4) no active carbon is consumed and the solvent can be recycled, thereby saving resources and being environmentally friendly.

Abstract: The invention relates to a method for preparing cadaverine comprising: (1) obtaining an aqueous cadaverine salt composition from a fermentation system; (2) adjusting the pH of the aqueous cadaverine salt composition to a pH of at least about 12 by adding an inorganic base composition to provide a first composition comprising an aqueous cadaverine composition having a pH of at least about 12 and a solid composition comprising one or more alkali metal sulfates; (3) subjecting the first composition to solid-liquid separation without organic solvent extraction to provide the aqueous cadaverine composition and the solid composition; (4) distilling or evaporating the aqueous cadaverine composition of step (3) without organic solvent extraction to provide purified cadaverine; (5) preparing a saturated solution of the alkali metal sulfate(s) from the solid composition of step (3) at a temperature of about 35-40° C.

Abstract: One aspect of the invention relates to a method for the purification of cadaverine from an aqueous cadaverine composition comprising one or more involatile impurities, the method comprising obtaining cadaverine from evaporation or distillation of the aqueous cadaverine composition wherein one or more solvents are added to the evaporation/distillation system before the evaporation/distillation starts, during the evaporation/distillation and/or after the evaporation/distillation substantially stops when no more evaporation/distillation is observed; wherein the one or more solvents comprise at least one or more high boiling point (HBP) solvents. In certain embodiments, cadaverine may be evaporated/distilled at an unexpectedly lower heating temperature for an unexpectedly shorter heating time to provide a desired yield. Because cadaverine may decompose at high temperature, the unexpectedly lower heating temperature and unexpectedly shorter heating time decrease the undesired cadaverine decomposition.

Abstract: One aspect of the invention relates to a method for reducing salt content in an aqueous cadaverine salt composition comprising adjusting the pH of the aqueous cadaverine salt composition to provide a first composition comprising an aqueous cadaverine composition and a solid composition, wherein the pH of the aqueous cadaverine composition is at least about 12; and removing the solid composition from the first composition to provide the aqueous cadaverine composition. Another aspect of the invention relates to a method for the purification of cadaverine from an aqueous cadaverine salt composition using the salt-reducing method described herein; and obtaining cadaverine from the aqueous cadaverine composition.

Abstract: One aspect of the present disclosure relates to a stabilized recombinant expression plasmid vector comprising a polynucleotide encoding an antitoxin gene which expresses a polypeptide that neutralizes a polypeptide toxic to a host cell, the toxic polypeptide being expressed by a toxin gene in the host cell, and a polynucleotide encoding a polypeptide expression product, and the stabilized recombinant expression plasmid vector is derived from a Hafnia alvei autonomously replicable backbone plasmid. Other aspects of the present disclosure relate to a transformant transformed with the stabilized recombinant expression plasmid vector disclosed herein, a method of producing biobased cadaverine using the transformant disclosed herein, and biobased cadaverine prepared by the method disclosed herein. Another aspect of the present disclosure relates to a polyamide formed using biobased cadaverine disclosed herein, and a composition thereof.

Abstract: A strain of Candida sake, CAT H430, is provided. The methods of using CAT H430 for producing dicarboxylic acids are also provided.

Abstract: One aspect of the present disclosure relates to a stabilized recombinant expression plasmid vector comprising a polynucleotide encoding an antitoxin gene which expresses a polypeptide that neutralizes a polypeptide toxic to a host cell, the toxic polypeptide being expressed by a toxin gene in the host cell, and a polynucleotide encoding a polypeptide expression product, and the stabilized recombinant expression plasmid vector is derived from a Hafnia alvei autonomously replicable backbone plasmid. Other aspects of the present disclosure relate to a transformant transformed with the stabilized recombinant expression plasmid vector disclosed herein, a method of producing biobased cadaverine using the transformant disclosed herein, and biobased cadaverine prepared by the method disclosed herein. Another aspect of the present disclosure relates to a polyamide formed using biobased cadaverine disclosed herein, and a composition thereof.

Abstract: One aspect of the invention relates to a method for the purification of cadaverine from an aqueous cadaverine composition comprising one or more involatile impurities, the method comprising obtaining cadaverine from evaporation or distillation of the aqueous cadaverine composition wherein one or more solvents are added to the evaporation/distillation system before the evaporation/distillation starts, during the evaporation/distillation and/or after the evaporation/distillation substantially stops when no more evaporation/distillation is observed; wherein the one or more solvents comprise at least one or more high boiling point (HBP) solvents. In certain embodiments, cadaverine may be evaporated/distilled at an unexpectedly lower heating temperature for an unexpectedly shorter heating time to provide a desired yield. Because cadaverine may decompose at high temperature, the unexpectedly lower heating temperature and unexpectedly shorter heating time decrease the undesired cadaverine decomposition.

Abstract: One aspect of the invention relates to a method for reducing salt content in an aqueous cadaverine salt composition comprising adjusting the pH of the aqueous cadaverine salt composition to provide a first composition comprising an aqueous cadaverine composition and a solid composition, and removing the solid composition from the first composition to provide the aqueous cadaverine composition. Another aspect of the invention relates to a method for the purification of cadaverine from an aqueous cadaverine salt composition using the salt-reducing method described herein; and obtaining cadaverine from the aqueous cadaverine composition.

Abstract: A strain of Candida sake, CAT H430, is provided. The methods of using CAT H430 for producing dicarboxylic acids are also provided.

Abstract: Disclosed is a process for treating a reaction solution containing a long chain dicarboxylate. The process is characterized by comprising: acidifying a reaction solution so as to convert the long chain dicarboxylate into a long chain dicarboxylic acid, adding an extractant so as to extract the resulting long chain dicarboxylic acid, separating the phase rich in the long chain dicarboxylic acid, and further separating the long chain dicarboxylic acid. The process of the present invention has the following advantages: 1) the processing route is simple, the operation time is short, less equipment is required, and the production efficiency is high; 2) product yield is high; 3) product quality is good, purity in the resulting products is high, and the color is lighter; and 4) no active carbon is consumed and the solvent can be recycled, thereby saving resources and being environmentally friendly.

Abstract: One aspect of the present disclosure relates to a stabilized recombinant expression plasmid vector comprising a polynucleotide encoding an antitoxin gene which expresses a polypeptide that neutralizes a polypeptide toxic to a host cell, the toxic polypeptide being expressed by a toxin gene in the host cell, and a polynucleotide encoding a polypeptide expression product, and the stabilized recombinant expression plasmid vector is derived from a Hafnia alvei autonomously replicable backbone plasmid. Other aspects of the present disclosure relate to a transformant transformed with the stabilized recombinant expression plasmid vector disclosed herein, a method of producing biobased cadaverine using the transformant disclosed herein, and biobased cadaverine prepared by the method disclosed herein. Another aspect of the present disclosure relates to a polyamide formed using biobased cadaverine disclosed herein, and a composition thereof.