Abstract: The present disclosure relates to time aware caching. One method includes receiving an API request for data from a database, wherein the request defines a time window associated with the data, creating a first and second query based on the request, wherein the first query corresponds to a first chunk of the time window, and wherein the second query corresponds to a second chunk of the time window, hashing a first statement associated with the first query to produce a first key and hashing a second statement associated with the second query to produce a second key, retrieving a first portion of the data corresponding to the first chunk of the time window from cache responsive to a determination that the first key is in the cache, and retrieving a second portion of the data corresponding to the second chunk of the time window from the database responsive to a determination that the second key is not in the cache.

Abstract: Provided is a method for purifying 1,5-pentanediamine comprising: providing 1,5-pentanediamine to be purified and treating the 1,5-pentanediamine to be purified by a reduction reaction to obtain purified 1,5-pentanediamine. Meanwhile, further provided is 1,5-pentanediamine prepared by the method. The purification method has a concise process and a simple operation, and is suitable for industrial production, and can significantly improve the quality of 1,5-pentanediamine.

Abstract: Provided are a lysine decarboxylase immobilized cell and preparation method thereof.

Abstract: Provided is a method for purifying 1,5-pentanediamine comprising: providing 1,5-pentanediamine to be purified and treating the 1,5-pentanediamine to be purified by a reduction reaction to obtain purified 1,5-pentanediamine. Meanwhile, further provided is 1,5-pentanediamine prepared by the method. The purification method has a concise process and a simple operation, and is suitable for industrial production, and can significantly improve the quality of 1,5-pentanediamine.

Abstract: Provided is a method for purifying 1,5-pentanediamine comprising: providing 1,5-pentanediamine to be purified and treating the 1,5-pentanediamine to be purified by a reduction reaction to obtain purified 1,5-pentanediamine. Meanwhile, further provided is 1,5-pentanediamine prepared by the method. The purification method has a concise process and a simple operation, and is suitable for industrial production, and can significantly improve the quality of 1,5-pentanediamine.

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 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 to provide an aqueous cadaverine composition having a pH of at least about 12; (2) distilling or evaporating the aqueous cadaverine composition to produce an aqueous cadaverine solution, 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 having a boiling point of at least 185° C. (1 atm); and (3) subjecting the aqueous cadaverine solution to one or more rectification steps to provide a cadaverine product.

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: 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 to provide an aqueous cadaverine composition having a pH of at least about 12; (2) distilling or evaporating the aqueous cadaverine composition to produce an aqueous cadaverine solution, 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 having a boiling point of at least 185° C. (1 atm); and (3) subjecting the aqueous cadaverine solution to one or more rectification steps to provide a cadaverine product.

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: 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: Provided is a method for purifying 1,5-pentanediamine comprising: providing 1,5-pentanediamine to be purified and treating the 1,5-pentanediamine to be purified by a reduction reaction to obtain purified 1,5-pentanediamine. Meanwhile, further provided is 1,5-pentanediamine prepared by the method. The purification method has a concise process and a simple operation, and is suitable for industrial production, and can significantly improve the quality of 1,5-pentanediamine.

Abstract: Provided are a lysine decarboxylase immobilized cell and preparation method thereof.

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: 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: 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: 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.