Abstract: Disclosed are a long-carbon-chain polyamide resin composition and a continuous fiber reinforced long-carbon-chain polyamide composite material. The long-carbon-chain polyamide resin composition includes the following components in parts by weight: 81.8-99.8 parts by mass of long-carbon-chain bio-based polyamide 5X resin, 0.2-1.6 parts by mass of an antioxidant, 0-0.8 parts by mass of a lubricant, 0-15 parts by mass of a compatibilizer, and 0-0.8 parts by mass of a coupling agent. The continuous fiber reinforced long-carbon-chain polyamide composite material prepared on the basis of the long-carbon-chain polyamide resin composition has high fiber content and good mechanical properties, is recyclable and can be used in fields of aerospace, military, automotive materials, sports equipment, building materials, electronic appliances, etc.

Abstract: Provided are a flame-retardant polyamide glass fiber composition and a preparation method therefor. The flame-retardant polyamide glass fiber comprising 40-65 parts by mass of a polyamide resin, 25-40 parts by mass of glass fibers, 0-20 parts by mass of a flame retardant, 0.2-1 part by mass of an antioxidant and 0.1-2 parts by mass of other auxiliaries. The flame-retardant polyamide glass fiber composition provided in the present disclosure not only has a bio-based source, but also has a flame-retardant of V-0 in UL94 and excellent mechanical properties, and can be widely applied to the fields of various engineering plastics with high requirements for flame retardant effect and dimensional stability.

Abstract: The present disclosure provides a system for extracting long chain dicarboxylic acid, the system comprising: a primary membrane filtration unit, a first crystallization unit, a first separation unit, a first dissolution tank, a secondary membrane filtration unit, a second separation unit, a second crystallization unit and a third separation unit. By the system for extracting long chain dicarboxylic acid of an embodiment of the present invention, the resulted long chain dicarboxylic acid product has a high purity, very low and even no residual alkane residue, and organic solvent-free.

Abstract: The present invention provides a decanedioic acid produced by microbial fermentation process, in which the content of C10 aliphatic acid and C10 hydroxy aliphatic acid is maintained at a very low level. The present invention also provides a preparation method of the decanedioic acid and a polymer prepared by using the decanedioic acid as monomer. The decanedioic acid provided by the present invention is prepared by microbial fermentation process. The decanedioic acid product which is produced through the processes of microbial fermentation and separation has a higher purity, a higher thermal stability, and a lower impurity content. The decanedioic acid provided by the present invention could satisfy the requirements of high grade product of polyamide or polyester to produce polymer with excellent qualities.

Abstract: Provided microorganisms genetically modified to overexpress an imine/enamine deaminase to enhance the production of lysine and lysine derivatives by the microorganism. Also provided a method of generating such microorganism, and methods of producing lysine and lysine derivatives using the genetically modified microorganisms.

Abstract: The invention is directed to a method of preparing a long chain dicarboxylic acid producing strain by using directed evolution and homologous recombination, a strain obtained by this method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use of the strain. In particular, the invention is directed to a method of preparing a long chain dicarboxylic acid producing strain by using directed evolution of CYP52A12 gene and homologous recombination, a strain obtained by this method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use of the strain.

Abstract: Provided are a Candida tropicalis strain Am2525, with the preservation number thereof being CCTCC NO: M 2019419, and a method for producing long-chain dicarboxylic acids by means of fermenting the strain. The method for producing the long-chain dicarboxylic acids comprises preparing a seed solution by means of the Candida tropicalis strain Am2525 and producing the long-chain dicarboxylic acids via fermentation of the seed solution. Compared with the parent, the Candida tropicalis strain Am2525 has an enhanced resistance to the toxicity of a substrate decane, improves the productivity of long-chain dicarboxylic acids, reduces the cost of production, subsequent separation and purification are simple, and the fermentation production process is easy to implement on a large scale.

Abstract: Disclosed are an industrial polyamide yarn, a preparation method therefor, and the use thereof. The raw materials for producing the industrial polyamide yarn include at least 1,5-pentanediamine and a linear aliphatic dibasic acid; or polyamide 5X obtained by the polymerization of 1,5-pentanediamine and a linear aliphatic dibasic acid as monomers. The industrial polyamide yarn according to an embodiment has the characteristics of a low water absorption, a good dimensional stability, a high fracture strength, and a good heat resistance.

Abstract: The present disclosure provides a polyamide 5X staple fiber, a preparation method and use thereof. The polyamide 5X staple fiber has a denier of 8.0-30.0D, a breaking strength of 2.0-6.0 cN/dtex, and an elongation at break of 30-100%. The polyamide 5X staple fiber has good mechanical properties and softness, and a blended wool yarn for manufacturing carpets with good mechanical properties, dyeability, and wear resistance can be obtained by using the polyamide 5X staple fiber.

Abstract: The invention provides CadA polypeptides with mutations that increase activity in alkaline pH compared to the wild-type lysine decarboxylase. The invention also provides methods of generating such mutant polypeptides, microorganisms genetically modified to overexpress the mutant polypeptides, and methods of generating such microorganism.

Abstract: The present disclosure provides methods for isolating a long chain dicarboxylic acid such as a substantially pure or pure long chain dicarboxylic acid from a fermentation broth containing microbial cells.

Abstract: The invention provides microorganisms genetically modified to overexpress biofilm dispersal related polypeptides to enhance the production of lysine and lysine derivatives by the microorganism, method of generating such microorganism, and methods of producing lysine and lysine derivatives using the genetically modified microorganisms.

Abstract: The present invention relates to a long-chain dibasic acid with low content of long-chain dibasic acid impurity of shorter carbon chain, to the preparation of a long-chain dibasic acid producing strain by directed evolution of POX gene and homologous recombination, and to the production of a long-chain dibasic acid with low content of long-chain dibasic acid impurity of shorter carbon chain by using the strain. The present invention also relates to a strain containing a mutated promoter, wherein, when a long-chain dibasic acid is produced by fermentation of this strain, the content of the acid impurity of shorter carbon chain in the fermentation product is significantly reduced.

Abstract: The present disclosure provides method for isolating a long chain dicarboxylic acid such as a substantially pure or pure long chain dicarboxylic acid from a fermentation broth containing microbial cells.

Abstract: The present invention discloses a method for producing a long chain dicarboxylic acid by fermentation as well as a fermentation broth, a treated fermentation broth and a wastewater. The salt content in the fermentation broth is controlled to be below 20% by the fermentation method of the present invention. The method for producing a long chain dicarboxylic acid by fermentation provided by the present invention can effectively reduce the amount of alkali used in the fermentation process and the amount of acid used in the subsequent extraction of the long chain dicarboxylic acid, thereby reducing the amount of salt in the whole production process of the long chain dicarboxylic acid. At the same time, the method of the present invention also has many advantages such as shortening the fermentation time, increasing the acid production, reducing the amount of medium, and suitable for the production of various types of long-chain dicarboxylic acids, etc.

Abstract: The present disclosure provides a system for extracting long chain dicarboxylic acid, the system comprising: a primary membrane filtration unit, a first crystallization unit, a first separation unit, a first dissolution tank, a secondary membrane filtration unit, a second separation unit, a second crystallization unit and a third separation unit. By the system for extracting long chain dicarboxylic acid of an embodiment of the present invention, the resulted long chain dicarboxylic acid product has a high purity, very low and even no residual alkane residue, and organic solvent-free.

Abstract: The present disclosure provides a method for extracting long chain dicarboxylic acid, the method comprising: (1) subjecting a long chain dicarboxylic acid fermentation broth to a primary membrane filtration treatment to give a first filtrate; subjecting the first filtrate to decolorization, crystallization, and solid-liquid separation to give a first solid; (2) redissolving the first solid in water to form a solution; subjecting the solution to decolorization, crystallization by acidification, and solid-liquid separation to give a second solid. By the method, the resulted long chain dicarboxylic acid product has a high purity and no residual organic solvent.

Abstract: The present disclosure provides a system for refining long chain dicarboxylic acid, comprising: a first membrane filtration unit, for a first membrane filtration of a long chain dicarboxylic acid fermentation broth or a treated liquid therefrom; a first decolorization unit, for carrying out a first decolorization treatment to the filtrate obtained after the membrane filtration; a first acidification/crystallization unit, for carrying out a first acidification/crystallization of a filtrate obtained after the membrane filtration to give a solid-liquid mixture; a first separation unit, for a solid-liquid separation of the solid-liquid mixture; a drying unit, for drying the solid separated by the separation unit to give a first solid. By using the refining system according to the present disclosure, the purity of the obtained product is high, and the disadvantages such as poor quality of the product obtained by crystallization from a solvent and environment pollution caused by a solvent can be overcome.

Abstract: One aspect provided herein relates to lysine decarboxylase polypeptides comprising mutants of SEQ ID NO: 2 (i.e., mutants of Klebsiella oxytoca (K. oxytoca) Ldc) and/or fragments thereof. In certain embodiments, the mutants or fragments thereof may have at least about 95% sequence identity with SEQ ID NO: 2. Another aspect provided herein relates to a DNA polynucleotide comprising one or more lysine decarboxylase nucleotide sequences of mutants of SEQ ID NO: 1 (i.e., mutants of K. oxytoca ldc), fragments thereof, or fragments of SEQ ID NO: 1 (i.e., fragments of K. oxytoca ldc). In certain embodiments, the DNA polynucleotide as disclosed herein may encode one or more lysine decarboxylase polypeptides provided herein. In certain embodiments, the DNA polynucleotide as disclosed herein may encode SEQ ID NO: 2, mutants, and/or fragments thereof. In certain embodiments, the lysine decarboxylase nucleotide sequences provided herein may have at least 95% sequence identity with SEQ ID NO: 1 or SEQ ID NO: 3.

Abstract: The present disclosure provides a method and a system for extracting long chain dicarboxylic acid, the method comprising: (1) subjecting a long chain dicarboxylic acid fermentation broth to a primary membrane filtration treatment to give a first filtrate; subjecting the first filtrate to decolorization, acidification/crystallization, and solid-liquid separation treatments to give a first solid; (2) mixing the first solid, a base and water to form a solution; subjecting the solution to a secondary membrane filtration treatment to give a second filtrate; subjecting the second filtrate to decolorization, acidification/crystallization, and solid-liquid separation treatments to give a second solid; and (3) mixing the second solid and water to form a mixture; subjecting the mixture to a thermostatic treatment at 105-150° C., followed by cooling for crystallization and solid-liquid separation treatment.